From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch adds support for file metadata (only TYPE_XATTR metadata type). gen_init_cpio has been modified to read xattrs from files that will be added to the image and to include file metadata as separate files with the special name 'METADATA!!!'.

This behavior can be selected by setting the desired file metadata type as value for CONFIG_INITRAMFS_FILE_METADATA.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- usr/Kconfig | 8 +++ usr/Makefile | 4 +- usr/gen_init_cpio.c | 136 +++++++++++++++++++++++++++++++++++++++++-- usr/gen_initramfs.sh | 7 ++- 4 files changed, 148 insertions(+), 7 deletions(-)

diff --git a/usr/Kconfig b/usr/Kconfig index 8bbcf699fe3b..be7a8ba66c44 100644 --- a/usr/Kconfig +++ b/usr/Kconfig @@ -227,3 +227,11 @@ config INITRAMFS_COMPRESSION_NONE filesystem image will be present in memory simultaneously

endchoice + +config INITRAMFS_FILE_METADATA + string "File metadata type" + default "" + help + Specify xattr to include xattrs in the image. + + If you are not sure, leave it blank. diff --git a/usr/Makefile b/usr/Makefile index 59d9e8b07a01..f82b6f74aa7b 100644 --- a/usr/Makefile +++ b/usr/Makefile @@ -64,7 +64,9 @@ quiet_cmd_initfs = GEN $@ $(CONFIG_SHELL) $< -o $@ -l $(obj)/.initramfs_data.cpio.d \ $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \ $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \ - $(ramfs-input) + $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \ + $(if $(filter-out "",$(CONFIG_INITRAMFS_FILE_METADATA)), \ + -e $(CONFIG_INITRAMFS_FILE_METADATA)) $(ramfs-input)

# We rebuild initramfs_data.cpio if: # 1) Any included file is newer than initramfs_data.cpio diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c index 61230532fef1..c9d403403bd3 100644 --- a/usr/gen_init_cpio.c +++ b/usr/gen_init_cpio.c @@ -5,6 +5,7 @@ #include <stdbool.h> #include <sys/types.h> #include <sys/stat.h> +#include <sys/xattr.h> #include <string.h> #include <unistd.h> #include <time.h> @@ -12,6 +13,7 @@ #include <errno.h> #include <ctype.h> #include <limits.h> +#include "../include/linux/initramfs.h"

/* * Original work by Jeff Garzik @@ -28,6 +30,115 @@ static unsigned int offset; static unsigned int ino = 721; static time_t default_mtime; static bool do_csum = false; +static char metadata_path[] = "/tmp/cpio-metadata-XXXXXX"; +static int metadata_fd = -1; + +static enum metadata_types parse_metadata_type(char *arg) +{ + static char *metadata_type_str[TYPE__LAST] = { + [TYPE_NONE] = "none", + [TYPE_XATTR] = "xattr", + }; + int i; + + for (i = 0; i < TYPE__LAST; i++) + if (!strcmp(metadata_type_str[i], arg)) + return i; + + return TYPE_NONE; +} + +static int cpio_mkfile(const char *name, const char *location, + unsigned int mode, uid_t uid, gid_t gid, + unsigned int nlinks); + +static int write_xattrs(const char *path) +{ + struct metadata_hdr hdr = { .c_version = 1, .c_type = TYPE_XATTR }; + char str[sizeof(hdr.c_size) + 1]; + char *xattr_list, *list_ptr, *xattr_value; + ssize_t list_len, name_len, value_len, len; + int ret = -EINVAL; + + if (metadata_fd < 0) + return 0; + + if (path == metadata_path) + return 0; + + list_len = listxattr(path, NULL, 0); + if (list_len <= 0) + return 0; + + list_ptr = xattr_list = malloc(list_len); + if (!list_ptr) { + fprintf(stderr, "out of memory\n"); + return ret; + } + + len = listxattr(path, xattr_list, list_len); + if (len != list_len) + goto out; + + if (ftruncate(metadata_fd, 0)) + goto out; + + lseek(metadata_fd, 0, SEEK_SET); + + while (list_ptr < xattr_list + list_len) { + name_len = strlen(list_ptr); + + value_len = getxattr(path, list_ptr, NULL, 0); + if (value_len < 0) { + fprintf(stderr, "cannot get xattrs\n"); + break; + } + + if (value_len) { + xattr_value = malloc(value_len); + if (!xattr_value) { + fprintf(stderr, "out of memory\n"); + break; + } + } else { + xattr_value = NULL; + } + + len = getxattr(path, list_ptr, xattr_value, value_len); + if (len != value_len) + break; + + snprintf(str, sizeof(str), "%.8lx", + sizeof(hdr) + name_len + 1 + value_len); + + memcpy(hdr.c_size, str, sizeof(hdr.c_size)); + + if (write(metadata_fd, &hdr, sizeof(hdr)) != sizeof(hdr)) + break; + + if (write(metadata_fd, list_ptr, name_len + 1) != name_len + 1) + break; + + if (write(metadata_fd, xattr_value, value_len) != value_len) + break; + + if (fsync(metadata_fd)) + break; + + list_ptr += name_len + 1; + free(xattr_value); + xattr_value = NULL; + } + + free(xattr_value); +out: + if (list_ptr != xattr_list + list_len) + return ret; + + free(xattr_list); + + return cpio_mkfile(METADATA_FILENAME, metadata_path, S_IFREG, 0, 0, 1); +}

struct file_handler { const char *type; @@ -132,7 +243,7 @@ static int cpio_mkslink(const char *name, const char *target, push_pad(); push_string(target); push_pad(); - return 0; + return write_xattrs(name); }

static int cpio_mkslink_line(const char *line) @@ -178,7 +289,7 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, 0); /* chksum */ push_hdr(s); push_rest(name); - return 0; + return write_xattrs(name); }

enum generic_types { @@ -272,7 +383,7 @@ static int cpio_mknod(const char *name, unsigned int mode, 0); /* chksum */ push_hdr(s); push_rest(name); - return 0; + return write_xattrs(name); }

static int cpio_mknod_line(const char *line) @@ -422,7 +533,7 @@ static int cpio_mkfile(const char *name, const char *location, name += namesize; } ino++; - rc = 0; + rc = write_xattrs(location);

error: if (file >= 0) @@ -577,10 +688,11 @@ int main (int argc, char *argv[]) int ec = 0; int line_nr = 0; const char *filename; + enum metadata_types metadata_type = TYPE_NONE;

default_mtime = time(NULL); while (1) { - int opt = getopt(argc, argv, "t:ch"); + int opt = getopt(argc, argv, "t:e:ch"); char *invalid;

if (opt == -1) @@ -595,6 +707,9 @@ int main (int argc, char *argv[]) exit(1); } break; + case 'e': + metadata_type = parse_metadata_type(optarg); + break; case 'c': do_csum = true; break; @@ -629,6 +744,14 @@ int main (int argc, char *argv[]) exit(1); }

+ if (metadata_type != TYPE_NONE) { + metadata_fd = mkstemp(metadata_path); + if (metadata_fd < 0) { + fprintf(stderr, "cannot create temporary file\n"); + exit(1); + } + } + while (fgets(line, LINE_SIZE, cpio_list)) { int type_idx; size_t slen = strlen(line); @@ -684,5 +807,8 @@ int main (int argc, char *argv[]) if (ec == 0) cpio_trailer();

+ if (metadata_type != TYPE_NONE) + close(metadata_fd); + exit(ec); } diff --git a/usr/gen_initramfs.sh b/usr/gen_initramfs.sh index 63476bb70b41..36648620d071 100755 --- a/usr/gen_initramfs.sh +++ b/usr/gen_initramfs.sh @@ -26,6 +26,7 @@ $0 [-o <file>] [-l <dep_list>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ... <cpio_source> File list or directory for cpio archive. If <cpio_source> is a .cpio file it will be used as direct input to initramfs. + -e <type> File metadata type to include in the cpio archive.

All options except -o and -l may be repeated and are interpreted sequentially and immediately. -u and -g states are preserved across @@ -218,6 +219,10 @@ while [ $# -gt 0 ]; do [ "$root_gid" = "-1" ] && root_gid=$(id -g || echo 0) shift ;; + "-e") # file metadata type + metadata_arg="-e $1" + shift + ;; "-h") usage exit 0 @@ -244,4 +249,4 @@ if test -n "$KBUILD_BUILD_TIMESTAMP"; then timestamp="-t $timestamp" fi fi -usr/gen_init_cpio $timestamp $cpio_list > $output +usr/gen_init_cpio $metadata_arg $timestamp $cpio_list > $output

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

IMA and EVM have been designed as two independent subsystems: the first for checking the integrity of file data; the second for checking file metadata. Making them independent allows users to adopt them incrementally.

The point of intersection is in IMA-Appraise, which calls evm_verifyxattr() to ensure that security.ima wasn't modified during an offline attack. The design choice, to ensure incremental adoption, was to continue appraisal verification if evm_verifyxattr() returns INTEGRITY_UNKNOWN. This value is returned when EVM is not enabled in the kernel configuration, or if the HMAC key has not been loaded yet.

Although this choice appears legitimate, it might not be suitable for hardened systems, where the administrator expects that access is denied if there is any error. An attacker could intentionally delete the EVM keys from the system and set the file digest in security.ima to the actual file digest so that the final appraisal status is INTEGRITY_PASS.

This patch allows such hardened systems to strictly enforce an access control policy based on the validity of signatures/HMACs, by introducing two new values for the ima_appraise= kernel option: enforce-evm and log-evm.

Cc: stable@vger.kernel.org Fixes: 2fe5d6def1672 ("ima: integrity appraisal extension") Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- Documentation/admin-guide/kernel-parameters.txt | 3 ++- security/integrity/ima/ima_appraise.c | 9 +++++++++ 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9e5bab29685f..ee50a3b91d73 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1941,7 +1941,8 @@ Set number of hash buckets for inode cache.

ima_appraise= [IMA] appraise integrity measurements - Format: { "off" | "enforce" | "fix" | "log" } + Format: { "off" | "enforce" | "fix" | "log" | + "enforce-evm" | "log-evm" } default: "enforce"

ima_appraise_tcb [IMA] Deprecated. Use ima_policy= instead. diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 491c1aca0b1c..08ae5d7faa1d 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -19,6 +19,7 @@

#include "ima.h"

+static bool ima_appraise_req_evm __ro_after_init; #ifdef CONFIG_IMA_APPRAISE_BOOTPARAM static char *ima_appraise_cmdline_default __initdata; core_param(ima_appraise, ima_appraise_cmdline_default, charp, 0); @@ -52,6 +53,10 @@ void __init ima_appraise_parse_cmdline(void) } else { ima_appraise = appraisal_state; } + + if (strcmp(str, "enforce-evm") == 0 || + strcmp(str, "log-evm") == 0) + ima_appraise_req_evm = true; } #endif

@@ -522,7 +527,11 @@ int ima_appraise_measurement(enum ima_hooks func, switch (status) { case INTEGRITY_PASS: case INTEGRITY_PASS_IMMUTABLE: + break; case INTEGRITY_UNKNOWN: + if (ima_appraise_req_evm && + xattr_value->type != EVM_IMA_XATTR_DIGSIG) + goto out; break; case INTEGRITY_NOXATTRS: /* No EVM protected xattrs. */ /* It's fine not to have xattrs when using a modsig. */

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch renames ima_read_policy() to ima_read_file() so that the function can be used to read files for different purposes. It also adds the opened file in securityfs as parameter so that the function can determine which action it should do with the passed data.

This patch replaces kernel_read_file_from_path() with filp_open() + kernel_read_file() so that the file descriptor can be used for further checks.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/ima/ima_fs.c | 50 ++++++++++++++++++++++----------- 1 file changed, 34 insertions(+), 16 deletions(-)

diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index cd1683dad3bf..cae42c5896bd 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -21,11 +21,20 @@ #include <linux/rcupdate.h> #include <linux/parser.h> #include <linux/vmalloc.h> +#include <linux/file.h>

#include "ima.h"

static DEFINE_MUTEX(ima_write_mutex);

+static struct dentry *ima_dir; +static struct dentry *ima_symlink; +static struct dentry *binary_runtime_measurements; +static struct dentry *ascii_runtime_measurements; +static struct dentry *runtime_measurements_count; +static struct dentry *violations; +static struct dentry *ima_policy; + bool ima_canonical_fmt; static int __init default_canonical_fmt_setup(char *str) { @@ -271,11 +280,13 @@ static const struct file_operations ima_ascii_measurements_ops = { .release = seq_release, };

-static ssize_t ima_read_policy(char *path) +static ssize_t ima_read_file(char *path, struct dentry *dentry) { void *data = NULL; char *datap; size_t size; + struct file *file; + enum kernel_read_file_id file_id = READING_POLICY; int rc, pathlen = strlen(path);

char *p; @@ -284,25 +295,39 @@ static ssize_t ima_read_policy(char *path) datap = path; strsep(&datap, "\n");

- rc = kernel_read_file_from_path(path, 0, &data, INT_MAX, NULL, - READING_POLICY); + file = filp_open(path, O_RDONLY, 0); + if (IS_ERR(file)) { + pr_err("Unable to open file: %s (%ld)", path, PTR_ERR(file)); + return PTR_ERR(file); + } + + rc = kernel_read_file(file, 0, &data, INT_MAX, NULL, file_id); if (rc < 0) { - pr_err("Unable to open file: %s (%d)", path, rc); + pr_err("Unable to read file: %s (%d)", path, rc); + fput(file); return rc; } size = rc; rc = 0;

datap = data; - while (size > 0 && (p = strsep(&datap, "\n"))) { - pr_debug("rule: %s\n", p); - rc = ima_parse_add_rule(p); + while (size > 0) { + if (dentry == ima_policy) { + p = strsep(&datap, "\n"); + if (p == NULL) + break; + + pr_debug("rule: %s\n", p); + rc = ima_parse_add_rule(p); + } + if (rc < 0) break; size -= rc; }

vfree(data); + fput(file); if (rc < 0) return rc; else if (size) @@ -316,6 +341,7 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf, { char *data; ssize_t result; + struct dentry *dentry = file_dentry(file);

if (datalen >= PAGE_SIZE) datalen = PAGE_SIZE - 1; @@ -336,7 +362,7 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf, goto out_free;

if (data[0] == '/') { - result = ima_read_policy(data); + result = ima_read_file(data, dentry); } else if (ima_appraise & IMA_APPRAISE_POLICY) { pr_err("signed policy file (specified as an absolute pathname) required\n"); integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL, @@ -356,14 +382,6 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf, return result; }

-static struct dentry *ima_dir; -static struct dentry *ima_symlink; -static struct dentry *binary_runtime_measurements; -static struct dentry *ascii_runtime_measurements; -static struct dentry *runtime_measurements_count; -static struct dentry *violations; -static struct dentry *ima_policy; - enum ima_fs_flags { IMA_FS_BUSY, };

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch renames ima_open_policy() and ima_release_policy() respectively to ima_open_data_upload() and ima_release_data_upload(). They will be used to implement file operations for interfaces allowing to load data from user space.

A new flag (IMA_POLICY_BUSY) has been defined to prevent concurrent policy upload.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/ima/ima_fs.c | 60 ++++++++++++++++++++++++--------- 1 file changed, 44 insertions(+), 16 deletions(-)

diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 57933bba19e8..b012f853f452 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -395,9 +395,20 @@ static ssize_t ima_write_data(struct file *file, const char __user *buf, }

enum ima_fs_flags { + IMA_POLICY_BUSY, IMA_FS_BUSY, };

+static enum ima_fs_flags ima_get_dentry_flag(struct dentry *dentry) +{ + enum ima_fs_flags flag = IMA_FS_BUSY; + + if (dentry == ima_policy) + flag = IMA_POLICY_BUSY; + + return flag; +} + static unsigned long ima_fs_flags;

#ifdef CONFIG_IMA_READ_POLICY @@ -410,40 +421,57 @@ static const struct seq_operations ima_policy_seqops = { #endif

/* - * ima_open_policy: sequentialize access to the policy file + * ima_open_data_upload: sequentialize access to the data upload interface */ -static int ima_open_policy(struct inode *inode, struct file *filp) +static int ima_open_data_upload(struct inode *inode, struct file *filp) { + struct dentry *dentry = file_dentry(filp); + const struct seq_operations *seq_ops = NULL; + enum ima_fs_flags flag = ima_get_dentry_flag(dentry); + bool read_allowed = false; + + if (dentry == ima_policy) { +#ifdef CONFIG_IMA_READ_POLICY + read_allowed = true; + seq_ops = &ima_policy_seqops; +#endif + } + if (!(filp->f_flags & O_WRONLY)) { -#ifndef CONFIG_IMA_READ_POLICY - return -EACCES; -#else + if (!read_allowed) + return -EACCES; if ((filp->f_flags & O_ACCMODE) != O_RDONLY) return -EACCES; if (!capable(CAP_SYS_ADMIN)) return -EPERM; - return seq_open(filp, &ima_policy_seqops); -#endif + return seq_open(filp, seq_ops); } - if (test_and_set_bit(IMA_FS_BUSY, &ima_fs_flags)) + if (test_and_set_bit(flag, &ima_fs_flags)) return -EBUSY; return 0; }

/* - * ima_release_policy - start using the new measure policy rules. + * ima_release_data_upload - start using the new measure policy rules. * * Initially, ima_measure points to the default policy rules, now * point to the new policy rules, and remove the securityfs policy file, * assuming a valid policy. */ -static int ima_release_policy(struct inode *inode, struct file *file) +static int ima_release_data_upload(struct inode *inode, struct file *file) { + struct dentry *dentry = file_dentry(file); const char *cause = valid_policy ? "completed" : "failed"; + enum ima_fs_flags flag = ima_get_dentry_flag(dentry);

if ((file->f_flags & O_ACCMODE) == O_RDONLY) return seq_release(inode, file);

+ if (dentry != ima_policy) { + clear_bit(flag, &ima_fs_flags); + return 0; + } + if (valid_policy && ima_check_policy() < 0) { cause = "failed"; valid_policy = 0; @@ -456,7 +484,7 @@ static int ima_release_policy(struct inode *inode, struct file *file) if (!valid_policy) { ima_delete_rules(); valid_policy = 1; - clear_bit(IMA_FS_BUSY, &ima_fs_flags); + clear_bit(flag, &ima_fs_flags); return 0; }

@@ -465,18 +493,18 @@ static int ima_release_policy(struct inode *inode, struct file *file) securityfs_remove(ima_policy); ima_policy = NULL; #elif defined(CONFIG_IMA_WRITE_POLICY) - clear_bit(IMA_FS_BUSY, &ima_fs_flags); + clear_bit(flag, &ima_fs_flags); #elif defined(CONFIG_IMA_READ_POLICY) inode->i_mode &= ~S_IWUSR; #endif return 0; }

-static const struct file_operations ima_measure_policy_ops = { - .open = ima_open_policy, +static const struct file_operations ima_data_upload_ops = { + .open = ima_open_data_upload, .write = ima_write_data, .read = seq_read, - .release = ima_release_policy, + .release = ima_release_data_upload, .llseek = generic_file_llseek, };

@@ -532,7 +560,7 @@ int __init ima_fs_init(void)

ima_policy = securityfs_create_file("policy", POLICY_FILE_FLAGS, ima_dir, NULL, - &ima_measure_policy_ops); + &ima_data_upload_ops); if (IS_ERR(ima_policy)) { ret = PTR_ERR(ima_policy); goto out;

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch introduces the parser of the compact digest list. The format is optimized to store a large quantity of data with the same type. It is the only format supported by the kernel. Digest lists can be uploaded by writing the path to securityfs, as the same as for IMA policies.

A compact list is a set of consecutive data blocks, each consisting of a header and a payload. The header indicates the version of the header, the type of data, type modifiers, the hash algorithm, how many elements and the length of the payload.

COMPACT_KEY identifies public keys used for signature verification of the digest lists; COMPACT_PARSER identifies digests of user space parsers allowed to directly upload parsed digest lists to the kernel; COMPACT_FILE identifies digests of regular files; COMPACT_METADATA identifies digest of file metadata.

Type modifiers indicate attributes of the elements included in the payload. The COMPACT_MOD_IMMUTABLE modifier indicates that a file or metadata are immutable.

This patch also introduces ima_lookup_loaded_digest() and ima_add_digest_data_entry() to search and add digests in the new hash table (ima_digests_htable).

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/ima/Kconfig | 10 ++ security/integrity/ima/Makefile | 1 + security/integrity/ima/ima_digest_list.c | 176 +++++++++++++++++++++++ security/integrity/ima/ima_digest_list.h | 32 +++++ security/integrity/integrity.h | 38 +++++ 5 files changed, 257 insertions(+) create mode 100644 security/integrity/ima/ima_digest_list.c create mode 100644 security/integrity/ima/ima_digest_list.h

diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index 60a511c6b583..cf130ae38827 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -338,3 +338,13 @@ config IMA_DISABLE_HTABLE default n help This option disables htable to allow measurement of duplicate records. + +config IMA_DIGEST_LIST + bool "Measure and appraise files with digest lists" + depends on IMA + default n + help + This option allows users to load digest lists. If calculated digests + of accessed files are found in one of those lists, no new entries are + added to the measurement list, and access to the file is granted if + appraisal is in enforcing mode. diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile index 2499f2485c04..fb9744a1c3d4 100644 --- a/security/integrity/ima/Makefile +++ b/security/integrity/ima/Makefile @@ -14,6 +14,7 @@ ima-$(CONFIG_HAVE_IMA_KEXEC) += ima_kexec.o ima-$(CONFIG_IMA_BLACKLIST_KEYRING) += ima_mok.o ima-$(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) += ima_asymmetric_keys.o ima-$(CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS) += ima_queue_keys.o +ima-$(CONFIG_IMA_DIGEST_LIST) += ima_digest_list.o

ifeq ($(CONFIG_EFI),y) ima-$(CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT) += ima_efi.o diff --git a/security/integrity/ima/ima_digest_list.c b/security/integrity/ima/ima_digest_list.c new file mode 100644 index 000000000000..0dcc69954887 --- /dev/null +++ b/security/integrity/ima/ima_digest_list.c @@ -0,0 +1,176 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2017-2019 Huawei Technologies Duesseldorf GmbH + * + * Author: Roberto Sassu roberto.sassu@huawei.com + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_digest_list.c + * Functions to manage digest lists. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/vmalloc.h> +#include <linux/module.h> + +#include "ima.h" +#include "ima_digest_list.h" + +struct ima_h_table ima_digests_htable = { + .len = ATOMIC_LONG_INIT(0), + .queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT +}; + +/************************* + * Get/add/del functions * + *************************/ +struct ima_digest *ima_lookup_digest(u8 *digest, enum hash_algo algo, + enum compact_types type) +{ + struct ima_digest *d = NULL; + int digest_len = hash_digest_size[algo]; + unsigned int key = ima_hash_key(digest); + + rcu_read_lock(); + hlist_for_each_entry_rcu(d, &ima_digests_htable.queue[key], hnext) + if (d->algo == algo && d->type == type && + !memcmp(d->digest, digest, digest_len)) + break; + + rcu_read_unlock(); + return d; +} + +static int ima_add_digest_data_entry(u8 *digest, enum hash_algo algo, + enum compact_types type, u16 modifiers) +{ + struct ima_digest *d; + int digest_len = hash_digest_size[algo]; + unsigned int key = ima_hash_key(digest); + + d = ima_lookup_digest(digest, algo, type); + if (d) { + d->modifiers |= modifiers; + if (d->count < (u16)(~((u16)0))) + d->count++; + return -EEXIST; + } + + d = kmalloc(sizeof(*d) + digest_len, GFP_KERNEL); + if (d == NULL) + return -ENOMEM; + + d->algo = algo; + d->type = type; + d->modifiers = modifiers; + d->count = 1; + + memcpy(d->digest, digest, digest_len); + hlist_add_head_rcu(&d->hnext, &ima_digests_htable.queue[key]); + atomic_long_inc(&ima_digests_htable.len); + return 0; +} + +static void ima_del_digest_data_entry(u8 *digest, enum hash_algo algo, + enum compact_types type) +{ + struct ima_digest *d; + + d = ima_lookup_digest(digest, algo, type); + if (!d) + return; + + if (--d->count > 0) + return; + + hlist_del_rcu(&d->hnext); + atomic_long_dec(&ima_digests_htable.len); +} + +/*********************** + * Compact list parser * + ***********************/ +struct compact_list_hdr { + u8 version; + u8 _reserved; + u16 type; + u16 modifiers; + u16 algo; + u32 count; + u32 datalen; +} __packed; + +int ima_parse_compact_list(loff_t size, void *buf, int op) +{ + u8 *digest; + void *bufp = buf, *bufendp = buf + size; + struct compact_list_hdr *hdr; + size_t digest_len; + int ret = 0, i; + + while (bufp < bufendp) { + if (bufp + sizeof(*hdr) > bufendp) { + pr_err("compact list, invalid data\n"); + return -EINVAL; + } + + hdr = bufp; + + if (hdr->version != 1) { + pr_err("compact list, unsupported version\n"); + return -EINVAL; + } + + if (ima_canonical_fmt) { + hdr->type = le16_to_cpu(hdr->type); + hdr->modifiers = le16_to_cpu(hdr->modifiers); + hdr->algo = le16_to_cpu(hdr->algo); + hdr->count = le32_to_cpu(hdr->count); + hdr->datalen = le32_to_cpu(hdr->datalen); + } + + if (hdr->algo >= HASH_ALGO__LAST) + return -EINVAL; + + digest_len = hash_digest_size[hdr->algo]; + + if (hdr->type >= COMPACT__LAST) { + pr_err("compact list, invalid type %d\n", hdr->type); + return -EINVAL; + } + + bufp += sizeof(*hdr); + + for (i = 0; i < hdr->count; i++) { + if (bufp + digest_len > bufendp) { + pr_err("compact list, invalid data\n"); + return -EINVAL; + } + + digest = bufp; + bufp += digest_len; + + if (op == DIGEST_LIST_OP_ADD) + ret = ima_add_digest_data_entry(digest, + hdr->algo, hdr->type, hdr->modifiers); + else if (op == DIGEST_LIST_OP_DEL) + ima_del_digest_data_entry(digest, hdr->algo, + hdr->type); + if (ret < 0 && ret != -EEXIST) + return ret; + } + + if (i != hdr->count || + bufp != (void *)hdr + sizeof(*hdr) + hdr->datalen) { + pr_err("compact list, invalid data\n"); + return -EINVAL; + } + } + + return bufp - buf; +} diff --git a/security/integrity/ima/ima_digest_list.h b/security/integrity/ima/ima_digest_list.h new file mode 100644 index 000000000000..ac6b0ee0aec6 --- /dev/null +++ b/security/integrity/ima/ima_digest_list.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2017-2019 Huawei Technologies Duesseldorf GmbH + * + * Author: Roberto Sassu roberto.sassu@huawei.com + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + * + * File: ima_digest_list.h + * Header of ima_digest_list.c + */ + +#ifndef __LINUX_IMA_DIGEST_LIST_H +#define __LINUX_IMA_DIGEST_LIST_H + +#define DIGEST_LIST_OP_ADD 0 +#define DIGEST_LIST_OP_DEL 1 + +#ifdef CONFIG_IMA_DIGEST_LIST +extern struct ima_h_table ima_digests_htable; + +int ima_parse_compact_list(loff_t size, void *buf, int op); +#else +static inline int ima_parse_compact_list(loff_t size, void *buf, int op) +{ + return -EOPNOTSUPP; +} +#endif /*CONFIG_IMA_DIGEST_LIST*/ +#endif /*LINUX_IMA_DIGEST_LIST_H*/ diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 7167a6e99bdc..5870b7459cef 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -18,6 +18,8 @@ #include <crypto/hash.h> #include <linux/key.h> #include <linux/audit.h> +#include <crypto/sha2.h> +#include <linux/hash_info.h>

/* iint action cache flags */ #define IMA_MEASURE 0x00000001 @@ -173,6 +175,42 @@ struct integrity_iint_cache { struct ima_digest_data *ima_hash; };

+enum compact_types { COMPACT_KEY, COMPACT_PARSER, COMPACT_FILE, + COMPACT_METADATA, COMPACT__LAST }; +enum compact_modifiers { COMPACT_MOD_IMMUTABLE, COMPACT_MOD__LAST }; + +struct ima_digest { + struct hlist_node hnext; + enum hash_algo algo; + enum compact_types type; + u16 modifiers; + u16 count; + u8 digest[0]; +}; + +static inline bool ima_digest_is_immutable(struct ima_digest *digest) +{ + return (digest->modifiers & (1 << COMPACT_MOD_IMMUTABLE)); +} + +#ifdef CONFIG_IMA_DIGEST_LIST +struct ima_digest *ima_lookup_digest(u8 *digest, enum hash_algo algo, + enum compact_types type); +struct ima_digest *ima_digest_allow(struct ima_digest *digest, int action); +#else +static inline struct ima_digest *ima_lookup_digest(u8 *digest, + enum hash_algo algo, + enum compact_types type) +{ + return NULL; +} +static inline struct ima_digest *ima_digest_allow(struct ima_digest *digest, + int action) +{ + return NULL; +} +#endif + /* rbtree tree calls to lookup, insert, delete * integrity data associated with an inode. */

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch introduces three new files in the securityfs filesystem. digest_list_data: loads a digest list from the specified path and adds the digests to the hash table; digest_list_data_del: does the same but removes the digests from the hash table; digests_count: shows the current number of digests stored in the hash table.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- include/linux/kernel_read_file.h | 1 + security/integrity/ima/ima_fs.c | 48 ++++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+)

diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h index 90451e2e12bd..a7724cd7c870 100644 --- a/include/linux/kernel_read_file.h +++ b/include/linux/kernel_read_file.h @@ -13,6 +13,7 @@ id(KEXEC_IMAGE, kexec-image) \ id(KEXEC_INITRAMFS, kexec-initramfs) \ id(POLICY, security-policy) \ + id(DIGEST_LIST, digest-list) \ id(X509_CERTIFICATE, x509-certificate) \ id(MAX_ID, )

diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 5d28e163db50..2998c3dfbc30 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -24,6 +24,7 @@ #include <linux/file.h>

#include "ima.h" +#include "ima_digest_list.h"

static DEFINE_MUTEX(ima_write_mutex);

@@ -34,6 +35,9 @@ static struct dentry *ascii_runtime_measurements; static struct dentry *runtime_measurements_count; static struct dentry *violations; static struct dentry *ima_policy; +static struct dentry *digests_count; +static struct dentry *digest_list_data; +static struct dentry *digest_list_data_del;

bool ima_canonical_fmt; static int __init default_canonical_fmt_setup(char *str) @@ -58,6 +62,10 @@ static ssize_t ima_show_htable_value(struct file *filp, char __user *buf, val = &ima_htable.violations; else if (filp->f_path.dentry == runtime_measurements_count) val = &ima_htable.len; +#ifdef CONFIG_IMA_DIGEST_LIST + else if (filp->f_path.dentry == digests_count) + val = &ima_digests_htable.len; +#endif

len = scnprintf(tmpbuf, sizeof(tmpbuf), "%li\n", atomic_long_read(val)); return simple_read_from_buffer(buf, count, ppos, tmpbuf, len); @@ -273,6 +281,7 @@ static ssize_t ima_read_file(char *path, struct dentry *dentry) size_t size; struct file *file; enum kernel_read_file_id file_id = READING_POLICY; + int op = DIGEST_LIST_OP_ADD; int rc, pathlen = strlen(path);

char *p; @@ -281,6 +290,9 @@ static ssize_t ima_read_file(char *path, struct dentry *dentry) datap = path; strsep(&datap, "\n");

+ if (dentry == digest_list_data || dentry == digest_list_data_del) + file_id = READING_DIGEST_LIST; + file = filp_open(path, O_RDONLY, 0); if (IS_ERR(file)) { pr_err("Unable to open file: %s (%ld)", path, PTR_ERR(file)); @@ -305,6 +317,18 @@ static ssize_t ima_read_file(char *path, struct dentry *dentry)

pr_debug("rule: %s\n", p); rc = ima_parse_add_rule(p); + } else if (dentry == digest_list_data || + dentry == digest_list_data_del) { + /* + * Disable usage of digest lists if not measured + * or appraised. + */ + ima_check_measured_appraised(file); + + if (dentry == digest_list_data_del) + op = DIGEST_LIST_OP_DEL; + + rc = ima_parse_compact_list(size, data, op); }

if (rc < 0) @@ -382,6 +406,7 @@ static ssize_t ima_write_data(struct file *file, const char __user *buf,

enum ima_fs_flags { IMA_POLICY_BUSY, + IMA_DIGEST_LIST_DATA_BUSY, IMA_FS_BUSY, };

@@ -391,6 +416,8 @@ static enum ima_fs_flags ima_get_dentry_flag(struct dentry *dentry)

if (dentry == ima_policy) flag = IMA_POLICY_BUSY; + else if (dentry == digest_list_data || dentry == digest_list_data_del) + flag = IMA_DIGEST_LIST_DATA_BUSY;

return flag; } @@ -551,10 +578,31 @@ int __init ima_fs_init(void) ret = PTR_ERR(ima_policy); goto out; } +#ifdef CONFIG_IMA_DIGEST_LIST + digests_count = securityfs_create_file("digests_count", + S_IRUSR | S_IRGRP, ima_dir, + NULL, &ima_htable_value_ops); + if (IS_ERR(digests_count)) + goto out;

+ digest_list_data = securityfs_create_file("digest_list_data", S_IWUSR, + ima_dir, NULL, + &ima_data_upload_ops); + if (IS_ERR(digest_list_data)) + goto out; + + digest_list_data_del = securityfs_create_file("digest_list_data_del", + S_IWUSR, ima_dir, NULL, + &ima_data_upload_ops); + if (IS_ERR(digest_list_data_del)) + goto out; +#endif return 0; out: securityfs_remove(ima_policy); + securityfs_remove(digest_list_data_del); + securityfs_remove(digest_list_data); + securityfs_remove(digests_count); securityfs_remove(violations); securityfs_remove(runtime_measurements_count); securityfs_remove(ascii_runtime_measurements);

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Digest lists should be uploaded to IMA as soon as possible, otherwise file digests would appear in the measurement list or access would be denied if appraisal is in enforcing mode.

This patch adds a call to ima_load_digest_lists() in integrity_load_keys(), so that the function is executed when rootfs becomes available, before files are accessed.

ima_load_digest_lists() iterates in the directory specified as value of CONFIG_IMA_DIGEST_LISTS_DIR and uploads all digest lists to the kernel.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/iint.c | 2 + security/integrity/ima/Kconfig | 8 ++ security/integrity/ima/ima_digest_list.c | 95 ++++++++++++++++++++++++ security/integrity/integrity.h | 4 + 4 files changed, 109 insertions(+)

diff --git a/security/integrity/iint.c b/security/integrity/iint.c index c73858e8c6d5..ecb9bd378a04 100644 --- a/security/integrity/iint.c +++ b/security/integrity/iint.c @@ -204,6 +204,8 @@ void __init integrity_load_keys(void)

if (!IS_ENABLED(CONFIG_IMA_LOAD_X509)) evm_load_x509(); + + ima_load_digest_lists(); }

static int __init integrity_fs_init(void) diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index cf130ae38827..73c582d97737 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -348,3 +348,11 @@ config IMA_DIGEST_LIST of accessed files are found in one of those lists, no new entries are added to the measurement list, and access to the file is granted if appraisal is in enforcing mode. + +config IMA_DIGEST_LISTS_DIR + string "Path of the directory containing digest lists" + depends on IMA_DIGEST_LIST + default "/etc/ima/digest_lists" + help + This option defines the path of the directory containing digest + lists. diff --git a/security/integrity/ima/ima_digest_list.c b/security/integrity/ima/ima_digest_list.c index 901990c8dfa8..91c70562aa86 100644 --- a/security/integrity/ima/ima_digest_list.c +++ b/security/integrity/ima/ima_digest_list.c @@ -17,6 +17,9 @@

#include <linux/vmalloc.h> #include <linux/module.h> +#include <linux/file.h> +#include <linux/namei.h> +#include <linux/xattr.h>

#include "ima.h" #include "ima_digest_list.h" @@ -222,3 +225,95 @@ struct ima_digest *ima_digest_allow(struct ima_digest *digest, int action)

return digest; } + +/************************************** + * Digest list loading at kernel init * + **************************************/ +struct readdir_callback { + struct dir_context ctx; + struct path *path; +}; + +static int __init load_digest_list(struct dir_context *__ctx, const char *name, + int namelen, loff_t offset, u64 ino, + unsigned int d_type) +{ + struct readdir_callback *ctx = container_of(__ctx, typeof(*ctx), ctx); + struct path *dir = ctx->path; + struct dentry *dentry; + struct file *file; + u8 *xattr_value = NULL; + void *datap = NULL; + loff_t size; + int ret; + + if (!strcmp(name, ".") || !strcmp(name, "..")) + return 0; + + dentry = lookup_one_len(name, dir->dentry, strlen(name)); + if (IS_ERR(dentry)) + return 0; + + size = vfs_getxattr(&nop_mnt_idmap, dentry, XATTR_NAME_EVM, NULL, 0); + if (size < 0) { + size = vfs_getxattr_alloc(&nop_mnt_idmap, dentry, XATTR_NAME_IMA, + (char **)&xattr_value, 0, GFP_NOFS); + if (size < 0 || xattr_value[0] != EVM_IMA_XATTR_DIGSIG) + goto out; + } + + file = file_open_root(dir, name, O_RDONLY, 0); + if (IS_ERR(file)) { + pr_err("Unable to open file: %s (%ld)", name, PTR_ERR(file)); + goto out; + } + + ret = kernel_read_file(file, 0, &datap, INT_MAX, NULL, + READING_DIGEST_LIST); + if (ret < 0) { + pr_err("Unable to read file: %s (%d)", name, ret); + goto out_fput; + } + + size = ret; + + ima_check_measured_appraised(file); + + ret = ima_parse_compact_list(size, datap, DIGEST_LIST_OP_ADD); + if (ret < 0) + pr_err("Unable to parse file: %s (%d)", name, ret); + + vfree(datap); +out_fput: + fput(file); +out: + kfree(xattr_value); + return 0; +} + +void __init ima_load_digest_lists(void) +{ + struct path path; + struct file *file; + int ret; + struct readdir_callback buf = { + .ctx.actor = load_digest_list, + }; + + if (!(ima_digest_list_actions & ima_policy_flag)) + return; + + ret = kern_path(CONFIG_IMA_DIGEST_LISTS_DIR, 0, &path); + if (ret) + return; + + file = dentry_open(&path, O_RDONLY, current_cred()); + if (IS_ERR(file)) + goto out; + + buf.path = &path; + iterate_dir(file, &buf.ctx); + fput(file); +out: + path_put(&path); +} diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 5870b7459cef..9b9c669634a9 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -197,6 +197,7 @@ static inline bool ima_digest_is_immutable(struct ima_digest *digest) struct ima_digest *ima_lookup_digest(u8 *digest, enum hash_algo algo, enum compact_types type); struct ima_digest *ima_digest_allow(struct ima_digest *digest, int action); +void __init ima_load_digest_lists(void); #else static inline struct ima_digest *ima_lookup_digest(u8 *digest, enum hash_algo algo, @@ -209,6 +210,9 @@ static inline struct ima_digest *ima_digest_allow(struct ima_digest *digest, { return NULL; } +static inline void ima_load_digest_lists(void) +{ +} #endif

/* rbtree tree calls to lookup, insert, delete

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

IMA-Appraise grants access to files with a valid signature or with actual file digest equal to the digest included in security.ima.

This patch adds support for appraisal based on digest lists. Instead of using the reference value from security.ima, this patch checks if the calculated file digest is included in the uploaded digest lists.

This functionality must be explicitly enabled by providing one of the following values for the ima_appraise_digest_list= kernel option:

- digest: this mode enables appraisal verification with digest lists until EVM is initialized; after that, EVM verification must be successful even if the file digest is found in a digest list;

- digest-nometadata: this mode enables appraisal verification with digest lists even after EVM has been initialized; files without security.evm are allowed if the digest of the content is found in the digest list, and security.evm is created with current values of xattrs (trust at first use); all files created in this way will have the new security.ima type EVM_IMA_XATTR_DIGEST_LIST; they can be accessed later only if this mode has been selected.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- .../admin-guide/kernel-parameters.txt | 9 ++ security/integrity/ima/ima.h | 6 +- security/integrity/ima/ima_appraise.c | 85 +++++++++++++++++-- security/integrity/ima/ima_main.c | 6 +- security/integrity/integrity.h | 1 + 5 files changed, 97 insertions(+), 10 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index b1e74fa1431a..da42ecb03667 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1945,6 +1945,15 @@ "enforce-evm" | "log-evm" } default: "enforce"

+ ima_appraise_digest_list= [IMA] + Format: { "digest" | "digest-nometadata" } + + digest: enables appraisal of files with digest lists + until EVM is initialized. + + digest-nometadata: enables appraisal of files with + digest lists even after EVM is initialized. + ima_appraise_tcb [IMA] Deprecated. Use ima_policy= instead. The builtin appraise policy appraises all files owned by uid=0. diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 8030bd78e4c2..124b4e78a784 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -324,7 +324,8 @@ int ima_appraise_measurement(enum ima_hooks func, struct integrity_iint_cache *iint, struct file *file, const unsigned char *filename, struct evm_ima_xattr_data *xattr_value, - int xattr_len, const struct modsig *modsig); + int xattr_len, const struct modsig *modsig, + struct ima_digest *found_digest); int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode, int mask, enum ima_hooks func); void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); @@ -344,7 +345,8 @@ static inline int ima_appraise_measurement(enum ima_hooks func, const unsigned char *filename, struct evm_ima_xattr_data *xattr_value, int xattr_len, - const struct modsig *modsig) + const struct modsig *modsig, + struct ima_digest *found_digest) { return INTEGRITY_UNKNOWN; } diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 274a0fec59f5..785849243048 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -18,6 +18,7 @@ #include <uapi/linux/fsverity.h>

#include "ima.h" +#include "ima_digest_list.h"

static bool ima_appraise_req_evm __ro_after_init; #ifdef CONFIG_IMA_APPRAISE_BOOTPARAM @@ -60,6 +61,22 @@ void __init ima_appraise_parse_cmdline(void) } #endif

+static bool ima_appraise_no_metadata __ro_after_init; +#ifdef CONFIG_IMA_DIGEST_LIST +static int __init appraise_digest_list_setup(char *str) +{ + if (!strncmp(str, "digest", 6)) { + ima_digest_list_actions |= IMA_APPRAISE; + + if (!strcmp(str + 6, "-nometadata")) + ima_appraise_no_metadata = true; + } + + return 1; +} +__setup("ima_appraise_digest_list=", appraise_digest_list_setup); +#endif + /* * is_ima_appraise_enabled - return appraise status * @@ -101,6 +118,9 @@ static int ima_fix_xattr(struct dentry *dentry, } else { offset = 0; iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG; + if (test_bit(IMA_DIGEST_LIST, &iint->atomic_flags)) + iint->ima_hash->xattr.ng.type = + EVM_IMA_XATTR_DIGEST_LIST; iint->ima_hash->xattr.ng.algo = algo; } rc = __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_IMA, @@ -271,20 +291,35 @@ static int calc_file_id_hash(enum evm_ima_xattr_type type, */ static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint, struct evm_ima_xattr_data *xattr_value, int xattr_len, - enum integrity_status *status, const char **cause) + enum integrity_status *status, const char **cause, + struct ima_digest *found_digest) { struct ima_max_digest_data hash; struct signature_v2_hdr *sig; int rc = -EINVAL, hash_start = 0; int mask;

+ if (found_digest && *status != INTEGRITY_PASS && + *status != INTEGRITY_PASS_IMMUTABLE) + set_bit(IMA_DIGEST_LIST, &iint->atomic_flags); + switch (xattr_value->type) { + case EVM_IMA_XATTR_DIGEST_LIST: + set_bit(IMA_DIGEST_LIST, &iint->atomic_flags); + + if (!ima_appraise_no_metadata) { + *cause = "IMA-xattr-untrusted"; + *status = INTEGRITY_FAIL; + break; + } + fallthrough; case IMA_XATTR_DIGEST_NG: /* first byte contains algorithm id */ hash_start = 1; fallthrough; case IMA_XATTR_DIGEST: - if (*status != INTEGRITY_PASS_IMMUTABLE) { + if (*status != INTEGRITY_PASS_IMMUTABLE && + (!found_digest || !ima_digest_is_immutable(found_digest))) { if (iint->flags & IMA_DIGSIG_REQUIRED) { if (iint->flags & IMA_VERITY_REQUIRED) *cause = "verity-signature-required"; @@ -472,14 +507,16 @@ int ima_appraise_measurement(enum ima_hooks func, struct integrity_iint_cache *iint, struct file *file, const unsigned char *filename, struct evm_ima_xattr_data *xattr_value, - int xattr_len, const struct modsig *modsig) + int xattr_len, const struct modsig *modsig, + struct ima_digest *found_digest) { static const char op[] = "appraise_data"; const char *cause = "unknown"; struct dentry *dentry = file_dentry(file); struct inode *inode = d_backing_inode(dentry); enum integrity_status status = INTEGRITY_UNKNOWN; - int rc = xattr_len; + int rc = xattr_len, rc_evm; + char _buf[sizeof(struct evm_ima_xattr_data) + 1 + SHA512_DIGEST_SIZE]; bool try_modsig = iint->flags & IMA_MODSIG_ALLOWED && modsig;

/* If not appraising a modsig, we need an xattr. */ @@ -490,6 +527,25 @@ int ima_appraise_measurement(enum ima_hooks func, xattr_len == sizeof(struct signature_v2_hdr)) rc = -ENODATA;

+ if (rc == -ENODATA && found_digest && + !(file->f_mode & FMODE_CREATED)) { + struct evm_ima_xattr_data *xattr_data = NULL; + + rc_evm = vfs_getxattr_alloc(&nop_mnt_idmap, dentry, XATTR_NAME_EVM, + (char **)&xattr_data, 0, GFP_NOFS); + if (rc_evm > 0) { + kfree(xattr_data); + } else { + xattr_value = (struct evm_ima_xattr_data *)_buf; + xattr_value->type = IMA_XATTR_DIGEST_NG; + xattr_value->data[0] = found_digest->algo; + memcpy(&xattr_value->data[1], found_digest->digest, + hash_digest_size[found_digest->algo]); + xattr_len = hash_digest_size[found_digest->algo] + 2; + rc = xattr_len; + } + } + /* If reading the xattr failed and there's no modsig, error out. */ if (rc <= 0 && !try_modsig) { if (rc && rc != -ENODATA) @@ -522,7 +578,7 @@ int ima_appraise_measurement(enum ima_hooks func, break; case INTEGRITY_UNKNOWN: if (ima_appraise_req_evm && - xattr_value->type != EVM_IMA_XATTR_DIGSIG) + xattr_value->type != EVM_IMA_XATTR_DIGSIG && !found_digest) goto out; break; case INTEGRITY_NOXATTRS: /* No EVM protected xattrs. */ @@ -531,6 +587,23 @@ int ima_appraise_measurement(enum ima_hooks func, break; fallthrough; case INTEGRITY_NOLABEL: /* No security.evm xattr. */ + /* + * If the digest-nometadata mode is selected, allow access + * without metadata check. EVM will eventually create an HMAC + * based on current xattr values. + */ + if (ima_appraise_no_metadata && found_digest) + break; + /* Allow access to digest lists without metadata, only if they + * are signed or found in a digest list (immutable) + */ + if (func == DIGEST_LIST_CHECK) { + if (xattr_value->type == EVM_IMA_XATTR_DIGSIG) + break; + if (found_digest && + ima_digest_is_immutable(found_digest)) + break; + } cause = "missing-HMAC"; goto out; case INTEGRITY_FAIL_IMMUTABLE: @@ -546,7 +619,7 @@ int ima_appraise_measurement(enum ima_hooks func,

if (xattr_value) rc = xattr_verify(func, iint, xattr_value, xattr_len, &status, - &cause); + &cause, found_digest);

/* * If we have a modsig and either no imasig or the imasig's key isn't diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index b3c8e9c21f5f..875dbd5d3de9 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -429,8 +429,10 @@ static int process_measurement(struct file *file, const struct cred *cred, if (rc != -EPERM) { inode_lock(inode); rc = ima_appraise_measurement(func, iint, file, - pathname, xattr_value, - xattr_len, modsig); + pathname, xattr_value, + xattr_len, modsig, + ima_digest_allow(found_digest, + IMA_APPRAISE)); inode_unlock(inode); } if (!rc) diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 538090a5f259..eea4adb46fdd 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -74,6 +74,7 @@ #define IMA_CHANGE_ATTR 2 #define IMA_DIGSIG 3 #define IMA_MUST_MEASURE 4 +#define IMA_DIGEST_LIST 5

enum evm_ima_xattr_type { IMA_XATTR_DIGEST = 0x01,

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Currently, IMA supports the appraise_type=imasig option in the policy to require file signatures. This patch introduces the new option appraise_type=meta_immutable to require that file metadata are signed and immutable. This requirement can be satisfied by portable signatures and by digest lists if they are marked as immutable.

The main purpose of this option is to ensure that file metadata are correct at the time of access, so that policies relying on labels can be correctly enforced. For example, requiring immutable metadata would prevent an administrator from altering the label assigned to a process during execve() by changing the label of the executable.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/ima/ima_appraise.c | 9 +++++++++ security/integrity/ima/ima_policy.c | 14 ++++++++++---- security/integrity/integrity.h | 1 + 3 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 785849243048..5eca0fb771aa 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -617,6 +617,15 @@ int ima_appraise_measurement(enum ima_hooks func, WARN_ONCE(true, "Unexpected integrity status %d\n", status); }

+ if ((iint->flags & IMA_META_IMMUTABLE_REQUIRED) && + status != INTEGRITY_PASS_IMMUTABLE) { + status = INTEGRITY_FAIL; + cause = "metadata-modifiable"; + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, + filename, op, cause, rc, 0); + goto out; + } + if (xattr_value) rc = xattr_verify(func, iint, xattr_value, xattr_len, &status, &cause, found_digest); diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 0c7f135bb556..66eaa0e0f66f 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -1251,7 +1251,8 @@ static bool ima_validate_rule(struct ima_rule_entry *entry)

if (entry->action != APPRAISE && entry->flags & (IMA_DIGSIG_REQUIRED | IMA_MODSIG_ALLOWED | - IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS)) + IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS | + IMA_META_IMMUTABLE_REQUIRED)) return false;

/* @@ -1285,7 +1286,7 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) IMA_FSNAME | IMA_GID | IMA_EGID | IMA_FGROUP | IMA_DIGSIG_REQUIRED | IMA_PERMIT_DIRECTIO | IMA_VALIDATE_ALGOS | - IMA_VERITY_REQUIRED)) + IMA_VERITY_REQUIRED | IMA_META_IMMUTABLE_REQUIRED)) return false;

break; @@ -1298,7 +1299,8 @@ static bool ima_validate_rule(struct ima_rule_entry *entry) IMA_FSNAME | IMA_GID | IMA_EGID | IMA_FGROUP | IMA_DIGSIG_REQUIRED | IMA_PERMIT_DIRECTIO | IMA_MODSIG_ALLOWED | - IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS)) + IMA_CHECK_BLACKLIST | IMA_VALIDATE_ALGOS | + IMA_META_IMMUTABLE_REQUIRED)) return false;

break; @@ -1824,7 +1826,9 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) else entry->flags |= IMA_DIGSIG_REQUIRED | IMA_MODSIG_ALLOWED; - } else { + } else if (strcmp(args[0].from, "meta_immutable") == 0) + entry->flags |= IMA_META_IMMUTABLE_REQUIRED; + else { result = -EINVAL; } break; @@ -2281,6 +2285,8 @@ int ima_policy_show(struct seq_file *m, void *v) seq_puts(m, "digest_type=verity "); if (entry->flags & IMA_CHECK_BLACKLIST) seq_puts(m, "appraise_flag=check_blacklist "); + if (entry->flags & IMA_META_IMMUTABLE_REQUIRED) + seq_puts(m, "appraise_type=meta_immutable "); if (entry->flags & IMA_PERMIT_DIRECTIO) seq_puts(m, "permit_directio "); rcu_read_unlock(); diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index eea4adb46fdd..a93ad2bcd809 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -43,6 +43,7 @@ #define IMA_MODSIG_ALLOWED 0x20000000 #define IMA_CHECK_BLACKLIST 0x40000000 #define IMA_VERITY_REQUIRED 0x80000000 +#define IMA_META_IMMUTABLE_REQUIRED 0x100000000

#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ IMA_HASH | IMA_APPRAISE_SUBMASK)

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch introduces a new hard-coded policy to appraise executable code:

appraise func=MODULE_CHECK appraise_type=imasig appraise func=FIRMWARE_CHECK appraise_type=imasig appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig appraise func=POLICY_CHECK appraise_type=imasig appraise func=DIGEST_LIST_CHECK appraise_type=imasig dont_appraise fsmagic=0x9fa0 dont_appraise fsmagic=0x62656572 dont_appraise fsmagic=0x64626720 dont_appraise fsmagic=0x858458f6 dont_appraise fsmagic=0x1cd1 dont_appraise fsmagic=0x42494e4d dont_appraise fsmagic=0x73636673 dont_appraise fsmagic=0xf97cff8c dont_appraise fsmagic=0x43415d53 dont_appraise fsmagic=0x6e736673 dont_appraise fsmagic=0xde5e81e4 dont_appraise fsmagic=0x27e0eb dont_appraise fsmagic=0x63677270 appraise func=BPRM_CHECK appraise_type=imasig appraise func=MMAP_CHECK appraise_type=imasig

The new policy can be selected by specifying ima_policy=appraise_exec_tcb in the kernel command line.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- .../admin-guide/kernel-parameters.txt | 5 ++++ security/integrity/ima/ima_policy.c | 28 +++++++++++++++++-- 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 81a3bae90bb3..28643f04d156 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2001,6 +2001,11 @@ of files (eg. kexec kernel image, kernel modules, firmware, policy, etc) based on file signatures.

+ The "appraise_exec_tcb" includes the "secure_boot" + policy and additionally includes all programs exec'd and + files mmap'd for exec. Files in the tmpfs filesystem are + not excluded from appraisal. + The "fail_securely" policy forces file signature verification failure also on privileged mounted filesystems with the SB_I_UNVERIFIABLE_SIGNATURE diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 863f0888b67d..22acd0c80afd 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -220,6 +220,13 @@ static struct ima_rule_entry default_appraise_rules[] __ro_after_init = { #endif };

+static struct ima_rule_entry appraise_exec_rules[] __ro_after_init = { + {.action = APPRAISE, .func = BPRM_CHECK, + .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED}, + {.action = APPRAISE, .func = MMAP_CHECK, + .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED}, +}; + static struct ima_rule_entry build_appraise_rules[] __ro_after_init = { #ifdef CONFIG_IMA_APPRAISE_REQUIRE_MODULE_SIGS {.action = APPRAISE, .func = MODULE_CHECK, @@ -277,6 +284,7 @@ static int __init default_measure_policy_setup(char *str) __setup("ima_tcb", default_measure_policy_setup);

static bool ima_use_appraise_tcb __initdata; +static bool ima_use_appraise_exec_tcb __initdata; static bool ima_use_secure_boot __initdata; static bool ima_use_critical_data __initdata; static bool ima_fail_unverifiable_sigs __ro_after_init; @@ -293,6 +301,8 @@ static int __init policy_setup(char *str) ima_policy = EXEC_TCB; else if (strcmp(p, "appraise_tcb") == 0) ima_use_appraise_tcb = true; + else if (strcmp(p, "appraise_exec_tcb") == 0) + ima_use_appraise_exec_tcb = true; else if (strcmp(p, "secure_boot") == 0) ima_use_secure_boot = true; else if (strcmp(p, "critical_data") == 0) @@ -885,6 +895,15 @@ static void __init add_rules(struct ima_rule_entry *entries, int count, continue; }

+ if (ima_use_appraise_exec_tcb) { + if (entries == default_appraise_rules) { + if (entries[i].action != DONT_APPRAISE) + continue; + if ((entries[i].flags & IMA_FSMAGIC) && + entries[i].fsmagic == TMPFS_MAGIC) + continue; + } + } if (policy_rule & IMA_DEFAULT_POLICY) list_add_tail(&entries[i].list, &ima_default_rules);

@@ -998,7 +1017,7 @@ void __init ima_init_policy(void) * Insert the builtin "secure_boot" policy rules requiring file * signatures, prior to other appraise rules. */ - if (ima_use_secure_boot) + if (ima_use_secure_boot || ima_use_appraise_exec_tcb) add_rules(secure_boot_rules, ARRAY_SIZE(secure_boot_rules), IMA_DEFAULT_POLICY);

@@ -1018,11 +1037,16 @@ void __init ima_init_policy(void) IMA_DEFAULT_POLICY | IMA_CUSTOM_POLICY); }

- if (ima_use_appraise_tcb) + if (ima_use_appraise_tcb || ima_use_appraise_exec_tcb) add_rules(default_appraise_rules, ARRAY_SIZE(default_appraise_rules), IMA_DEFAULT_POLICY);

+ if (ima_use_appraise_exec_tcb) + add_rules(appraise_exec_rules, + ARRAY_SIZE(appraise_exec_rules), + IMA_DEFAULT_POLICY); + if (ima_use_critical_data) add_rules(critical_data_rules, ARRAY_SIZE(critical_data_rules),

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch adds the documentation of the IMA Digest Lists extension.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- Documentation/security/IMA-digest-lists.txt | 259 ++++++++++++++++++++ 1 file changed, 259 insertions(+) create mode 100644 Documentation/security/IMA-digest-lists.txt

diff --git a/Documentation/security/IMA-digest-lists.txt b/Documentation/security/IMA-digest-lists.txt new file mode 100644 index 000000000000..15f30deab328 --- /dev/null +++ b/Documentation/security/IMA-digest-lists.txt @@ -0,0 +1,259 @@ +========================== +IMA Digest Lists Extension +========================== + +INTRODUCTION +============ + +Integrity Measurement Architecture (IMA) is a security module that performs +measurement of files accessed with the execve(), mmap() and open() system +calls. File measurements can be used for different purposes. They can be +added in a measurement list and sent to a remote verifier for an integrity +evaluation. They can be compared to reference values provided by the +software vendor and access can be denied if there is a mismatch. File +measurements can also be included in system logs for auditing purposes. + +IMA Digest Lists is an extension providing additional functionality for +the IMA submodules and EVM. Its main task is to load reference values for +file content and metadata in the kernel memory, and to communicate to IMA +submodules (measurement and appraisal) or EVM whether the digest of a file +being accessed is found in the uploaded digest lists. + +The IMA-Measure submodule uses the IMA Digest Lists extension to create +a new measurement list (with a different PCR, for example 11) which +contains the measurement of uploaded digest lists and unknown files. Since +the loading of digest lists is sequential, the chosen PCR will have a +predictable value for the whole boot cycle and can be used for sealing +policies based on the OS software integrity. + +Both the standard and the new measurement list can be generated at the same +time, allowing for implicit attestation based on the usage of a TPM key +sealed to the OS, and for explicit attestation when a more precise +integrity evaluation is necessary. + +The IMA-Appraise submodule uses the IMA Digest Lists extension to +grant/deny access to the files depending on whether the file digest is +found in the uploaded digest lists, instead of checking security.ima. + +EVM uses the IMA Digest Lists extension to check file metadata integrity. + +The main advantage of the extension is that reference measurements used for +the digest comparison can be extracted from already existing sources (for +example RPM headers). Another benefit is that the overhead compared to file +signatures is lower as only one signature is verified for all files +included in the digest list. + + + +WORKFLOW +======== + +The IMA workflow is modified as follows. The added steps are marked as +[NEW]. + + +------------+ + | IMA hook | + +------------+ + | + +---------+ + | collect | + +---------+ + | +---------------------+ ++---------------+ ------------| don't measure [NEW] | +| digest lookup | | yes +---------------------+ +| [NEW] | -------------- no +---------------------+ ++---------------+ -----/ digest ---| add to measurement | + | | \ found? [NEW] / | list (PCR 11) [NEW] | + | | -------------- +---------------------+ + +----------+ +-------------+ +--------------------+ + | switch |-------| IMA-Measure |----------------| add to measurement | + | (action) | +-------------+ | list (PCR 10) | + +----------+ +--------------------+ + | + | + | no xattr ++--------------+ --------------- yes +| IMA-Appraise |----/ filec created ------------------------------- ++--------------+ \ created [NEW] / | + xattr | --------------- | + | | no | + | ------------------ no -------------- yes +--------+ + | / EVM initialized? ----/ digest ------| grant | + | \ [NEW] / \ found? [NEW] / | access | + | ------------------ -------------- +--------+ + | | yes | no + | | | +--------+ + | ------------------- no ---------------| deny | + | / digest-nometadata -------------------------| access | + | \ mode? [NEW] / +--------+ + | ------------------- + | ^ | yes +--------+ + | | -------------------------------------| grant | + | | | access | + | | +--------+ + | | yes + | ------------------------- no +--------+ + |----------/ security.ima (new type) -------------------| deny | + | \ present and valid? / | access | + | ------------------------- +--------+ + | | + | -------------------------- no | + -----------/ security.ima (cur types) ----------------------- + \ present and valid? / + -------------------------- + | yes +--------+ + ------------------------------------| grant | + | access | + +--------+ + + ++-----+ -------------------------- yes +--------+ +| EVM |---------/ security.evm (cur types) ---------------------| grant | ++-----+ \ present and valid? / | access | + | -------------------------- +--------+ + | | + | | no +--------+ + | ------------------------------------| deny | + | | access | + | +--------+ + | | + | +-----------+ | + | ------------------------- | calculate | | + -------------/ security.evm (new type) ---| metadata | | + \ present? [NEW] / | digest | | + ------------------------- +-----------+ | + | | + -------------- no | + / digest --------- + \ found? [NEW] / + -------------- +--------+ + | yes | grant | + | | access | + | +--------+ + | | + ------------------ yes | + / digest -----| + \ immutable? [NEW] / | + ------------------ | + | no | + +---------+ | + | convert |------------ + | to HMAC | + +---------+ + + +After the file digest is calculated, it is searched in the hash table +containing all digests extracted from the uploaded digest lists. Then, if +the digest is found, a structure is returned to IMA with information +associated to that digest. The structure is returned only to the IMA +submodules that processed the digest lists (i.e. the action returned by +ima_get_action() was 'measure' or 'appraise'). + +IMA-Measure behavior depends on whether the digest list PCR has been +specified in the kernel command line. If the PCR was not specified, the +submodule behaves as before. If the PCR was specified, IMA-Measure creates +a new measurement with that PCR, only if the file digest is not found in +the digest lists. It additionally creates a measurement with the default +PCR if '+' is added as a prefix to the PCR. + +IMA-Appraise behavior depends on whether either the 'digest' or +'digest-nometadata' appraisal modes have been specified in the kernel +command line. If they were not specified, IMA-Appraise relies solely on the +security.ima xattr for verification. If the 'digest' mode was specified, +verification succeeds if the file digest is found in the digest lists and +EVM is not initialized, as there is no other way to verify file metadata. + +If the 'digest-nometadata' mode was specified, verification succeeds +regardless of the fact that EVM is initialized or not. However, after a +write, files for which access was granted without verifying metadata will +have a new security.ima type, so that they can be identified also after +reboot. Specifying 'digest-nometadata' is required also to access files +with the new security.ima type. + +EVM determines whether metadata digest should be searched in the digest +lists depending on the security.evm type. If the new type is set, EVM +calculates metadata digest and searches it in the digest lists. A structure +is returned to EVM if the digest is found and the digest lists were +appraised. + + + +ARCHITECTURE +============ + ++-----+ 6) digest lookup +| EVM |------------------------------------------------ ++-----+ | + | ++--------------+ 5) digest lookup | +| IMA-Appraise |--------------------------------------| ++--------------+ || + || ++-------------+ 4) digest lookup || +| IMA-Measure | -------------------------------------|| ++-------------+ ||| + ||| ++-------------+ 2) parse compact list +-------------------+ +| IMA (secfs) | ------------------------> | IMA Digests Lists | ++-------------+ +-------------------+ + ^ | 3) add digests + | +------------+ + | | hash table | + | +------------+ + | + | kernel space +---|------------------------------------------------------------------------- + | user space + | + | + | + | + | + | + | +1) echo <digest list path> + +The main addition to IMA is a new hash table (similar to that used to check +for duplicate measurement entries), which contains file content and metadata +digests extracted from the digest lists. + +Digest lists can be uploaded to the kernel by writing their path to +digest_list_data in the securityfs filesystem. After digest lists are +uploaded, they are parsed by the kernel and extracted digests are added to +the hash table. + +IMA submodules, Measure and Appraise, search the digest of an accessed file +in the hash table and perform actions depending on whether the digest was +found or not. IMA submodules can search digests in the hash table only if +they also processed the digest lists. + +EVM searches the metadata digest of an accessed file in the hash table and +returns the result to IMA, which perform actions depending on the result. +EVM can search digests in the hash table if IMA-Appraise processed the +digest lists. + + + +CONFIGURATION +============= + +The first step consists in generating digest lists with the +gen_digest_lists tool included in the digest-list-tools package. +digest-list-tools can be retrieved at the URL: + +https://gitee.com/openeuler/digest-list-tools + +gen_digest_lists can generate digest lists from different sources (for +example: RPM package DB). By default, it saves generated digest lists in +the /etc/ima/digest_lists directory. digest-list-tools includes also two +bash scripts setup_ima_digest_lists and setup_digest_lists_demo to simplify +the digest list generation for the users. + +To use digest lists during early boot, it is necessary to regenerate the +initial ram disk. Digest lists will be added to the ram disk by the new +dracut/initramfs-tools modules, included in the digest-list-tools package. To +include file signatures in the initial ram disk, it is necessary to have the +following patches applied: + +https://gitee.com/src-openeuler/cpio/blob/master/add-option-to-add-metadata-... +https://gitee.com/src-openeuler/dracut/blob/master/add-option-to-include-fil...

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Parse the RSA key with RAW format if the ASN.1 parser returns an error.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- crypto/rsa.c | 14 +++++-- crypto/rsa_helper.c | 69 +++++++++++++++++++++++++++++++++++ include/crypto/internal/rsa.h | 6 +++ 3 files changed, 85 insertions(+), 4 deletions(-)

diff --git a/crypto/rsa.c b/crypto/rsa.c index c50f2d2a4d06..0ca65c1db3a9 100644 --- a/crypto/rsa.c +++ b/crypto/rsa.c @@ -216,8 +216,11 @@ static int rsa_set_pub_key(struct crypto_akcipher *tfm, const void *key, rsa_free_mpi_key(mpi_key);

ret = rsa_parse_pub_key(&raw_key, key, keylen); - if (ret) - return ret; + if (ret) { + ret = rsa_parse_pub_key_raw(&raw_key, key, keylen); + if (ret) + return ret; + }

mpi_key->e = mpi_read_raw_data(raw_key.e, raw_key.e_sz); if (!mpi_key->e) @@ -250,8 +253,11 @@ static int rsa_set_priv_key(struct crypto_akcipher *tfm, const void *key, rsa_free_mpi_key(mpi_key);

ret = rsa_parse_priv_key(&raw_key, key, keylen); - if (ret) - return ret; + if (ret) { + ret = rsa_parse_priv_key_raw(&raw_key, key, keylen); + if (ret) + return ret; + }

mpi_key->d = mpi_read_raw_data(raw_key.d, raw_key.d_sz); if (!mpi_key->d) diff --git a/crypto/rsa_helper.c b/crypto/rsa_helper.c index 94266f29049c..fb9443df8f0b 100644 --- a/crypto/rsa_helper.c +++ b/crypto/rsa_helper.c @@ -9,6 +9,7 @@ #include <linux/export.h> #include <linux/err.h> #include <linux/fips.h> +#include <linux/mpi.h> #include <crypto/internal/rsa.h> #include "rsapubkey.asn1.h" #include "rsaprivkey.asn1.h" @@ -148,6 +149,32 @@ int rsa_get_qinv(void *context, size_t hdrlen, unsigned char tag, return 0; }

+typedef int (*rsa_get_func)(void *, size_t, unsigned char, + const void *, size_t); + +static int rsa_parse_key_raw(struct rsa_key *rsa_key, + const void *key, unsigned int key_len, + rsa_get_func *func, int n_func) +{ + unsigned int nbytes, len = key_len; + const void *key_ptr = key; + int ret, i; + + for (i = 0; i < n_func; i++) { + ret = mpi_key_length(key_ptr, len, NULL, &nbytes); + if (ret < 0) + return ret; + + ret = func[i](rsa_key, 0, 0, key_ptr + 2, nbytes); + if (ret < 0) + return ret; + + key_ptr += nbytes + 2; + } + + return (key_ptr == key + key_len) ? 0 : -EINVAL; +} + /** * rsa_parse_pub_key() - decodes the BER encoded buffer and stores in the * provided struct rsa_key, pointers to the raw key as is, @@ -166,6 +193,27 @@ int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key, } EXPORT_SYMBOL_GPL(rsa_parse_pub_key);

+/** + * rsa_parse_pub_key_raw() - parse the RAW key and store in the provided struct + * rsa_key, pointers to the raw key as is, so that + * the caller can copy it or MPI parse it, etc. + * + * @rsa_key: struct rsa_key key representation + * @key: key in RAW format + * @key_len: length of key + * + * Return: 0 on success or error code in case of error + */ +int rsa_parse_pub_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len) +{ + rsa_get_func pub_func[] = {rsa_get_n, rsa_get_e}; + + return rsa_parse_key_raw(rsa_key, key, key_len, + pub_func, ARRAY_SIZE(pub_func)); +} +EXPORT_SYMBOL_GPL(rsa_parse_pub_key_raw); + /** * rsa_parse_priv_key() - decodes the BER encoded buffer and stores in the * provided struct rsa_key, pointers to the raw key @@ -184,3 +232,24 @@ int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key, return asn1_ber_decoder(&rsaprivkey_decoder, rsa_key, key, key_len); } EXPORT_SYMBOL_GPL(rsa_parse_priv_key); + +/** + * rsa_parse_priv_key_raw() - parse the RAW key and store in the provided struct + * rsa_key, pointers to the raw key as is, so that + * the caller can copy it or MPI parse it, etc. + * + * @rsa_key: struct rsa_key key representation + * @key: key in RAW format + * @key_len: length of key + * + * Return: 0 on success or error code in case of error + */ +int rsa_parse_priv_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len) +{ + rsa_get_func priv_func[] = {rsa_get_n, rsa_get_e, rsa_get_d}; + + return rsa_parse_key_raw(rsa_key, key, key_len, + priv_func, ARRAY_SIZE(priv_func)); +} +EXPORT_SYMBOL_GPL(rsa_parse_priv_key_raw); diff --git a/include/crypto/internal/rsa.h b/include/crypto/internal/rsa.h index e870133f4b77..7141e806ceea 100644 --- a/include/crypto/internal/rsa.h +++ b/include/crypto/internal/rsa.h @@ -50,8 +50,14 @@ struct rsa_key { int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key, unsigned int key_len);

+int rsa_parse_pub_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len); + int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key, unsigned int key_len);

+int rsa_parse_priv_key_raw(struct rsa_key *rsa_key, const void *key, + unsigned int key_len); + extern struct crypto_template rsa_pkcs1pad_tmpl; #endif

From: David Howells dhowells@redhat.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Provide a simple parser that extracts the packets from a PGP packet blob and passes the desirous ones to the given processor function:

struct pgp_parse_context { u64 types_of_interest; int (*process_packet)(struct pgp_parse_context *context, enum pgp_packet_tag type, u8 headerlen, const u8 *data, size_t datalen); };

int pgp_parse_packets(const u8 *data, size_t datalen, struct pgp_parse_context *ctx);

This is configured on with CONFIG_PGP_LIBRARY.

Changelog

v0: - fix style issues (Roberto Sassu) - declare pgp_to_public_key_algo (Roberto Sassu)

Signed-off-by: David Howells dhowells@redhat.com Co-developed-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- crypto/asymmetric_keys/Kconfig | 6 + crypto/asymmetric_keys/Makefile | 5 + crypto/asymmetric_keys/pgp_library.c | 281 +++++++++++++++++++++++++++ crypto/asymmetric_keys/pgp_parser.h | 23 +++ include/linux/pgplib.h | 48 +++++ 5 files changed, 363 insertions(+) create mode 100644 crypto/asymmetric_keys/pgp_library.c create mode 100644 crypto/asymmetric_keys/pgp_parser.h create mode 100644 include/linux/pgplib.h

diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 1ef3b46d6f6e..00791af8de8e 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -85,4 +85,10 @@ config FIPS_SIGNATURE_SELFTEST depends on ASYMMETRIC_KEY_TYPE depends on PKCS7_MESSAGE_PARSER=X509_CERTIFICATE_PARSER

+config PGP_LIBRARY + tristate "PGP parsing library" + help + This option enables a library that provides a number of simple + utility functions for parsing PGP (RFC 4880) packet-based messages. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index 0d1fa1b692c6..5417575ac3bc 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -76,3 +76,8 @@ verify_signed_pefile-y := \

$(obj)/mscode_parser.o: $(obj)/mscode.asn1.h $(obj)/mscode.asn1.h $(obj)/mscode.asn1.o: $(obj)/mscode.asn1.c $(obj)/mscode.asn1.h + +# +# PGP handling +# +obj-$(CONFIG_PGP_LIBRARY) += pgp_library.o diff --git a/crypto/asymmetric_keys/pgp_library.c b/crypto/asymmetric_keys/pgp_library.c new file mode 100644 index 000000000000..be307f426f75 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_library.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0 +/* PGP packet parser (RFC 4880) + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#define pr_fmt(fmt) "PGPL: "fmt +#include <linux/pgplib.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> + +MODULE_LICENSE("GPL"); + +const char *const pgp_hash_algorithms[PGP_HASH__LAST] = { + [PGP_HASH_MD5] = "md5", + [PGP_HASH_SHA1] = "sha1", + [PGP_HASH_RIPE_MD_160] = "rmd160", + [PGP_HASH_SHA256] = "sha256", + [PGP_HASH_SHA384] = "sha384", + [PGP_HASH_SHA512] = "sha512", + [PGP_HASH_SHA224] = "sha224", +}; +EXPORT_SYMBOL_GPL(pgp_hash_algorithms); + +const char *pgp_to_public_key_algo[PGP_PUBKEY__LAST] = { + [PGP_PUBKEY_RSA_ENC_OR_SIG] = "rsa", + [PGP_PUBKEY_RSA_ENC_ONLY] = "rsa", + [PGP_PUBKEY_RSA_SIG_ONLY] = "rsa", + [PGP_PUBKEY_ELGAMAL] = NULL, + [PGP_PUBKEY_DSA] = NULL, +}; +EXPORT_SYMBOL_GPL(pgp_to_public_key_algo); + +/** + * pgp_parse_packet_header - Parse a PGP packet header + * @_data: Start of the PGP packet (updated to PGP packet data) + * @_datalen: Amount of data remaining in buffer (decreased) + * @_type: Where the packet type will be returned + * @_headerlen: Where the header length will be returned + * + * Parse a set of PGP packet header [RFC 4880: 4.2]. + * + * Returns packet data size on success; non-zero on error. If successful, + * *_data and *_datalen will have been updated and *_headerlen will be set to + * hold the length of the packet header. + */ +static ssize_t pgp_parse_packet_header(const u8 **_data, size_t *_datalen, + enum pgp_packet_tag *_type, + u8 *_headerlen) +{ + enum pgp_packet_tag type; + const u8 *data = *_data; + size_t size, datalen = *_datalen; + + pr_devel("-->%s(,%zu,,)\n", __func__, datalen); + + if (datalen < 2) + goto short_packet; + + pr_devel("pkthdr %02x, %02x\n", data[0], data[1]); + + type = *data++; + datalen--; + if (!(type & 0x80)) { + pr_debug("Packet type does not have MSB set\n"); + return -EBADMSG; + } + type &= ~0x80; + + if (type & 0x40) { + /* New packet length format */ + type &= ~0x40; + pr_devel("new format: t=%u\n", type); + switch (data[0]) { + case 0x00 ... 0xbf: + /* One-byte length */ + size = data[0]; + data++; + datalen--; + *_headerlen = 2; + break; + case 0xc0 ... 0xdf: + /* Two-byte length */ + if (datalen < 2) + goto short_packet; + size = (data[0] - 192) * 256; + size += data[1] + 192; + data += 2; + datalen -= 2; + *_headerlen = 3; + break; + case 0xff: + /* Five-byte length */ + if (datalen < 5) + goto short_packet; + size = data[1] << 24; + size |= data[2] << 16; + size |= data[3] << 8; + size |= data[4]; + data += 5; + datalen -= 5; + *_headerlen = 6; + break; + default: + pr_debug("Partial body length packet not supported\n"); + return -EBADMSG; + } + } else { + /* Old packet length format */ + u8 length_type = type & 0x03; + + type >>= 2; + pr_devel("old format: t=%u lt=%u\n", type, length_type); + + switch (length_type) { + case 0: + /* One-byte length */ + size = data[0]; + data++; + datalen--; + *_headerlen = 2; + break; + case 1: + /* Two-byte length */ + if (datalen < 2) + goto short_packet; + size = data[0] << 8; + size |= data[1]; + data += 2; + datalen -= 2; + *_headerlen = 3; + break; + case 2: + /* Four-byte length */ + if (datalen < 4) + goto short_packet; + size = data[0] << 24; + size |= data[1] << 16; + size |= data[2] << 8; + size |= data[3]; + data += 4; + datalen -= 4; + *_headerlen = 5; + break; + default: + pr_debug("Indefinite length packet not supported\n"); + return -EBADMSG; + } + } + + pr_devel("datalen=%zu size=%zu", datalen, size); + if (datalen < size) + goto short_packet; + if ((int)size < 0) + goto too_big; + + *_data = data; + *_datalen = datalen; + *_type = type; + pr_devel("Found packet type=%u size=%zd\n", type, size); + return size; + +short_packet: + pr_debug("Attempt to parse short packet\n"); + return -EBADMSG; +too_big: + pr_debug("Signature subpacket size >2G\n"); + return -EMSGSIZE; +} + +/** + * pgp_parse_packets - Parse a set of PGP packets + * @_data: Data to be parsed (updated) + * @_datalen: Amount of data (updated) + * @ctx: Parsing context + * + * Parse a set of PGP packets [RFC 4880: 4]. + */ +int pgp_parse_packets(const u8 *data, size_t datalen, + struct pgp_parse_context *ctx) +{ + enum pgp_packet_tag type; + ssize_t pktlen; + u8 headerlen; + int ret; + + while (datalen > 2) { + pktlen = pgp_parse_packet_header(&data, &datalen, &type, + &headerlen); + if (pktlen < 0) + return pktlen; + + if ((ctx->types_of_interest >> type) & 1) { + ret = ctx->process_packet(ctx, type, headerlen, + data, pktlen); + if (ret < 0) + return ret; + } + data += pktlen; + datalen -= pktlen; + } + + if (datalen != 0) { + pr_debug("Excess octets in packet stream\n"); + return -EBADMSG; + } + + return 0; +} +EXPORT_SYMBOL_GPL(pgp_parse_packets); + +/** + * pgp_parse_public_key - Parse the common part of a PGP pubkey packet + * @_data: Content of packet (updated) + * @_datalen: Length of packet remaining (updated) + * @pk: Public key data + * + * Parse the common data struct for a PGP pubkey packet [RFC 4880: 5.5.2]. + */ +int pgp_parse_public_key(const u8 **_data, size_t *_datalen, + struct pgp_parse_pubkey *pk) +{ + const u8 *data = *_data; + size_t datalen = *_datalen; + unsigned int tmp; + + if (datalen < 12) { + pr_debug("Public key packet too short\n"); + return -EBADMSG; + } + + pk->version = *data++; + switch (pk->version) { + case PGP_KEY_VERSION_2: + case PGP_KEY_VERSION_3: + case PGP_KEY_VERSION_4: + break; + default: + pr_debug("Public key packet with unhandled version %d\n", + pk->version); + return -EBADMSG; + } + + tmp = *data++ << 24; + tmp |= *data++ << 16; + tmp |= *data++ << 8; + tmp |= *data++; + pk->creation_time = tmp; + if (pk->version == PGP_KEY_VERSION_4) { + pk->expires_at = 0; /* Have to get it from the selfsignature */ + } else { + unsigned short ndays; + + ndays = *data++ << 8; + ndays |= *data++; + if (ndays) + pk->expires_at = pk->creation_time + ndays * 86400UL; + else + pk->expires_at = 0; + datalen -= 2; + } + + pk->pubkey_algo = *data++; + datalen -= 6; + + pr_devel("%x,%x,%lx,%lx\n", + pk->version, pk->pubkey_algo, pk->creation_time, + pk->expires_at); + + *_data = data; + *_datalen = datalen; + return 0; +} +EXPORT_SYMBOL_GPL(pgp_parse_public_key); diff --git a/crypto/asymmetric_keys/pgp_parser.h b/crypto/asymmetric_keys/pgp_parser.h new file mode 100644 index 000000000000..56f9a2b48679 --- /dev/null +++ b/crypto/asymmetric_keys/pgp_parser.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* PGP crypto data parser internal definitions + * + * Copyright (C) 2011 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include <linux/pgp.h> + +#define kenter(FMT, ...) \ + pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__) +#define kleave(FMT, ...) \ + pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__) + +/* + * pgp_library.c + */ +extern const char *pgp_to_public_key_algo[PGP_PUBKEY__LAST]; diff --git a/include/linux/pgplib.h b/include/linux/pgplib.h new file mode 100644 index 000000000000..a4068bcef8c5 --- /dev/null +++ b/include/linux/pgplib.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* PGP library definitions (RFC 4880) + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#ifndef _LINUX_PGPLIB_H +#define _LINUX_PGPLIB_H + +#if IS_ENABLED(CONFIG_PGP_LIBRARY) || IS_ENABLED(CONFIG_PGP_LIBRARY_MODULE) + +#include <linux/pgp.h> + +/* + * PGP library packet parser + */ +struct pgp_parse_context { + u64 types_of_interest; + int (*process_packet)(struct pgp_parse_context *context, + enum pgp_packet_tag type, + u8 headerlen, + const u8 *data, + size_t datalen); +}; + +extern int pgp_parse_packets(const u8 *data, size_t datalen, + struct pgp_parse_context *ctx); + +struct pgp_parse_pubkey { + enum pgp_key_version version : 8; + enum pgp_pubkey_algo pubkey_algo : 8; + __kernel_old_time_t creation_time; + __kernel_old_time_t expires_at; +}; + +extern int pgp_parse_public_key(const u8 **_data, size_t *_datalen, + struct pgp_parse_pubkey *pk); + + +#endif /* CONFIG_PGP_LIBRARY */ + +#endif /* _LINUX_PGPLIB_H */

From: David Howells dhowells@redhat.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Provide a facility to autogenerate the name of PGP keys from the contents of the payload. If add_key() is given a blank description, a description is constructed from the last user ID packet in the payload data plus the last 8 hex digits of the key ID. For instance:

keyctl padd asymmetric "" @s </tmp/key.pub

might create a key with a constructed description that can be seen in /proc/keys:

2f674b96 I--Q--- 1 perm 39390000 0 0 crypto \ Sample kernel key 31f0ae93: PGP.RSA 31f0ae93 []

Changelog

v0: - fix style issues (Roberto Sassu)

Signed-off-by: David Howells dhowells@redhat.com Co-developed-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- crypto/asymmetric_keys/pgp_public_key.c | 46 ++++++++++++++++++++++++- 1 file changed, 45 insertions(+), 1 deletion(-)

diff --git a/crypto/asymmetric_keys/pgp_public_key.c b/crypto/asymmetric_keys/pgp_public_key.c index 49913b346c18..27b9efeafc4f 100644 --- a/crypto/asymmetric_keys/pgp_public_key.c +++ b/crypto/asymmetric_keys/pgp_public_key.c @@ -36,6 +36,9 @@ struct pgp_key_data_parse_context { struct public_key *pub; unsigned char *raw_fingerprint; char *fingerprint; + const char *user_id; + size_t user_id_len; + size_t fingerprint_len; };

/* @@ -156,6 +159,7 @@ static int pgp_generate_fingerprint(struct pgp_key_data_parse_context *ctx, if (ret < 0) goto cleanup_raw_fingerprint;

+ ctx->fingerprint_len = digest_size * 2; fingerprint = kmalloc(digest_size * 2 + 1, GFP_KERNEL); if (!fingerprint) goto cleanup_raw_fingerprint; @@ -200,6 +204,13 @@ static int pgp_process_public_key(struct pgp_parse_context *context,

kenter(",%u,%u,,%zu", type, headerlen, datalen);

+ if (type == PGP_PKT_USER_ID) { + ctx->user_id = data; + ctx->user_id_len = datalen; + kleave(" = 0 [user ID]"); + return 0; + } + if (ctx->fingerprint) { kleave(" = -ENOKEY [already]"); return -EBADMSG; @@ -292,13 +303,46 @@ static int pgp_key_parse(struct key_preparsed_payload *prep) kenter("");

memset(&ctx, 0, sizeof(ctx)); - ctx.pgp.types_of_interest = (1 << PGP_PKT_PUBLIC_KEY); + ctx.pgp.types_of_interest = (1 << PGP_PKT_PUBLIC_KEY) | + (1 << PGP_PKT_USER_ID); ctx.pgp.process_packet = pgp_process_public_key;

ret = pgp_parse_packets(prep->data, prep->datalen, &ctx.pgp); if (ret < 0) goto error;

+ if (ctx.user_id && ctx.user_id_len > 0) { + /* Propose a description for the key + * (user ID without the comment) + */ + size_t ulen = ctx.user_id_len, flen = ctx.fingerprint_len; + const char *p; + + p = memchr(ctx.user_id, '(', ulen); + if (p) { + /* Remove the comment */ + do { + p--; + } while (*p == ' ' && p > ctx.user_id); + if (*p != ' ') + p++; + ulen = p - ctx.user_id; + } + + if (ulen > 255 - 9) + ulen = 255 - 9; + prep->description = kmalloc(ulen + 1 + 8 + 1, GFP_KERNEL); + ret = -ENOMEM; + if (!prep->description) + goto error; + memcpy(prep->description, ctx.user_id, ulen); + prep->description[ulen] = ' '; + memcpy(prep->description + ulen + 1, + ctx.fingerprint + flen - 8, 8); + prep->description[ulen + 9] = 0; + pr_debug("desc '%s'\n", prep->description); + } + /* We're pinning the module by being linked against it */ __module_get(public_key_subtype.owner); prep->payload.data[asym_subtype] = &public_key_subtype;

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Preload PGP keys from 'pubring.gpg', placed in certs/ of the kernel source directory.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- certs/Kconfig | 7 +++++++ certs/Makefile | 7 +++++++ certs/system_certificates.S | 18 ++++++++++++++++++ certs/system_keyring.c | 22 ++++++++++++++++++++++ 4 files changed, 54 insertions(+)

diff --git a/certs/Kconfig b/certs/Kconfig index 1f109b070877..3038adbaf58d 100644 --- a/certs/Kconfig +++ b/certs/Kconfig @@ -138,4 +138,11 @@ config SYSTEM_BLACKLIST_AUTH_UPDATE keyring. The PKCS#7 signature of the description is set in the key payload. Blacklist keys cannot be removed.

+config PGP_PRELOAD_PUBLIC_KEYS + bool "Preload PGP public keys" + select PGP_PRELOAD + default n + help + Provide a keyring of PGP public keys. + endmenu diff --git a/certs/Makefile b/certs/Makefile index 799ad7b9e68a..ab6da6f4e953 100644 --- a/certs/Makefile +++ b/certs/Makefile @@ -65,6 +65,13 @@ endif # CONFIG_MODULE_SIG_KEY

$(obj)/system_certificates.o: $(obj)/signing_key.x509

+ifdef CONFIG_PGP_PRELOAD_PUBLIC_KEYS +ifeq ($(shell ls $(srctree)/certs/pubring.gpg 2> /dev/null), $(srctree)/certs/pubring.gpg) +system_certificates.o += -DHAVE_PUBRING_GPG +$(obj)/system_certificates.o: $(srctree)/certs/pubring.gpg +endif +endif + PKCS11_URI := $(filter pkcs11:%, $(CONFIG_MODULE_SIG_KEY)) ifdef PKCS11_URI $(obj)/signing_key.x509: extract-cert-in := $(PKCS11_URI) diff --git a/certs/system_certificates.S b/certs/system_certificates.S index 003e25d4a17e..b3cbf0811e3f 100644 --- a/certs/system_certificates.S +++ b/certs/system_certificates.S @@ -44,3 +44,21 @@ module_cert_size: #else .long __module_cert_end - __module_cert_start #endif + + .align 8 + .globl pgp_public_keys +pgp_public_keys: +__pgp_key_list_start: +#ifdef HAVE_PUBRING_GPG + .incbin "certs/pubring.gpg" +#endif +__pgp_key_list_end: + + .align 8 + .globl pgp_public_keys_size +pgp_public_keys_size: +#ifdef CONFIG_64BIT + .quad __pgp_key_list_end - __pgp_key_list_start +#else + .long __pgp_key_list_end - __pgp_key_list_start +#endif diff --git a/certs/system_keyring.c b/certs/system_keyring.c index a7a49b17ceb1..da4a8b470cbb 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -11,6 +11,7 @@ #include <linux/cred.h> #include <linux/err.h> #include <linux/slab.h> +#include <linux/pgp.h> #include <linux/uidgid.h> #include <linux/verification.h> #include <keys/asymmetric-type.h> @@ -216,6 +217,27 @@ static __init int load_system_certificate_list(void) } late_initcall(load_system_certificate_list);

+#ifdef CONFIG_PGP_PRELOAD_PUBLIC_KEYS +extern __initconst const u8 pgp_public_keys[]; +extern __initconst const unsigned long pgp_public_keys_size; + +/* + * Load a list of PGP keys. + */ +static __init int load_pgp_public_keyring(void) +{ + pr_notice("Load PGP public keys\n"); + + if (preload_pgp_keys(pgp_public_keys, + pgp_public_keys_size, + builtin_trusted_keys) < 0) + pr_err("Can't load PGP public keys\n"); + + return 0; +} +late_initcall(load_pgp_public_keyring); +#endif /* CONFIG_PGP_PRELOAD_PUBLIC_KEYS */ + #ifdef CONFIG_SYSTEM_DATA_VERIFICATION

/**

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Introduce search_trusted_key() to extend the key search to the primary or secondary built-in keyrings.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- certs/system_keyring.c | 22 ++++++++++++++++++++++ include/linux/verification.h | 4 ++++ 2 files changed, 26 insertions(+)

diff --git a/certs/system_keyring.c b/certs/system_keyring.c index da4a8b470cbb..e9770f4e5449 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -361,6 +361,28 @@ int verify_pkcs7_signature(const void *data, size_t len, } EXPORT_SYMBOL_GPL(verify_pkcs7_signature);

+struct key *search_trusted_key(struct key *trusted_keys, struct key_type *type, + char *name) +{ + key_ref_t kref; + + if (!trusted_keys) { + trusted_keys = builtin_trusted_keys; + } else if (trusted_keys == VERIFY_USE_SECONDARY_KEYRING) { +#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING + trusted_keys = secondary_trusted_keys; +#else + trusted_keys = builtin_trusted_keys; +#endif + } + kref = keyring_search(make_key_ref(trusted_keys, 1), type, name, true); + if (IS_ERR(kref)) + return ERR_CAST(kref); + + return key_ref_to_ptr(kref); +} +EXPORT_SYMBOL_GPL(search_trusted_key); + #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */

#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING diff --git a/include/linux/verification.h b/include/linux/verification.h index f34e50ebcf60..4eac691f82b6 100644 --- a/include/linux/verification.h +++ b/include/linux/verification.h @@ -9,6 +9,7 @@ #define _LINUX_VERIFICATION_H

#include <linux/types.h> +#include <linux/key.h>

/* * Indicate that both builtin trusted keys and secondary trusted keys @@ -68,5 +69,8 @@ extern int verify_pefile_signature(const void *pebuf, unsigned pelen, enum key_being_used_for usage); #endif

+struct key *search_trusted_key(struct key *trusted_keys, struct key_type *type, + char *name); + #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ #endif /* _LINUX_VERIFY_PEFILE_H */

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

This patch allows direct upload of digest lists by user space parsers. This operation is possible if the digest of the process's executable is found in the digest lists and its type is COMPACT_PARSER.

ima_check_measured_appraised() is called at the end of ima_file_check() to verify that everything accessed by the user space parsers (except for directories and securityfs) has been processed by IMA. If a digest list was not processed by an IMA submodule, digest list lookup is disabled for that submodule.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/ima/ima_appraise.c | 2 +- security/integrity/ima/ima_digest_list.c | 56 ++++++++++++++++++++++++ security/integrity/ima/ima_digest_list.h | 18 ++++++++ security/integrity/ima/ima_fs.c | 22 ++++++++++ security/integrity/ima/ima_main.c | 40 ++++++++++------- 5 files changed, 120 insertions(+), 18 deletions(-)

diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 5eca0fb771aa..cdcc20339c8e 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -597,7 +597,7 @@ int ima_appraise_measurement(enum ima_hooks func, /* Allow access to digest lists without metadata, only if they * are signed or found in a digest list (immutable) */ - if (func == DIGEST_LIST_CHECK) { + if (func == DIGEST_LIST_CHECK || ima_current_is_parser()) { if (xattr_value->type == EVM_IMA_XATTR_DIGSIG) break; if (found_digest && diff --git a/security/integrity/ima/ima_digest_list.c b/security/integrity/ima/ima_digest_list.c index 42b2306e43cc..b5d1004e3040 100644 --- a/security/integrity/ima/ima_digest_list.c +++ b/security/integrity/ima/ima_digest_list.c @@ -20,6 +20,8 @@ #include <linux/file.h> #include <linux/namei.h> #include <linux/xattr.h> +#include <linux/sched/mm.h> +#include <linux/magic.h>

#include "ima.h" #include "ima_digest_list.h" @@ -216,6 +218,10 @@ void ima_check_measured_appraised(struct file *file) if (!ima_digest_list_actions) return;

+ if (file_inode(file)->i_sb->s_magic == SECURITYFS_MAGIC || + S_ISDIR(file_inode(file)->i_mode)) + return; + iint = integrity_iint_find(file_inode(file)); if (!iint) { pr_err("%s not processed, disabling digest lists lookup\n", @@ -342,3 +348,53 @@ void __init ima_load_digest_lists(void) out: path_put(&path); } + +/**************** + * Parser check * + ****************/ +bool ima_check_current_is_parser(void) +{ + struct integrity_iint_cache *parser_iint; + struct file *parser_file; + struct mm_struct *mm; + + mm = get_task_mm(current); + if (!mm) + return false; + + parser_file = get_mm_exe_file(mm); + mmput(mm); + + if (!parser_file) + return false; + + parser_iint = integrity_iint_find(file_inode(parser_file)); + fput(parser_file); + + if (!parser_iint) + return false; + + /* flag cannot be cleared due to write protection of executables */ + if (!(parser_iint->flags & IMA_COLLECTED)) + return false; + + return ima_lookup_digest(parser_iint->ima_hash->digest, + parser_iint->ima_hash->algo, COMPACT_PARSER); +} + +struct task_struct *parser_task; + +void ima_set_parser(void) +{ + parser_task = current; +} + +void ima_unset_parser(void) +{ + parser_task = NULL; +} + +bool ima_current_is_parser(void) +{ + return (current == parser_task); +} diff --git a/security/integrity/ima/ima_digest_list.h b/security/integrity/ima/ima_digest_list.h index 5bd2388ff95e..4a8b0e000ad3 100644 --- a/security/integrity/ima/ima_digest_list.h +++ b/security/integrity/ima/ima_digest_list.h @@ -24,6 +24,10 @@ extern struct ima_h_table ima_digests_htable;

int ima_parse_compact_list(loff_t size, void *buf, int op); void ima_check_measured_appraised(struct file *file); +bool ima_check_current_is_parser(void); +void ima_set_parser(void); +void ima_unset_parser(void); +bool ima_current_is_parser(void); #else static inline int ima_parse_compact_list(loff_t size, void *buf, int op) { @@ -32,5 +36,19 @@ static inline int ima_parse_compact_list(loff_t size, void *buf, int op) static inline void ima_check_measured_appraised(struct file *file) { } +static inline bool ima_check_current_is_parser(void) +{ + return false; +} +static inline void ima_set_parser(void) +{ +} +static inline void ima_unset_parser(void) +{ +} +static inline bool ima_current_is_parser(void) +{ + return false; +} #endif /*CONFIG_IMA_DIGEST_LIST*/ #endif /*LINUX_IMA_DIGEST_LIST_H*/ diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 2998c3dfbc30..7310683a7af7 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -390,6 +390,20 @@ static ssize_t ima_write_data(struct file *file, const char __user *buf, } else { result = ima_parse_add_rule(data); } + } else if (dentry == digest_list_data) { + if (!ima_current_is_parser()) { + result = -EACCES; + } else { + result = ima_parse_compact_list(datalen, data, + DIGEST_LIST_OP_ADD); + } + } else if (dentry == digest_list_data_del) { + if (!ima_current_is_parser()) { + result = -EACCES; + } else { + result = ima_parse_compact_list(datalen, data, + DIGEST_LIST_OP_DEL); + } } else { pr_err("Unknown data type\n"); result = -EINVAL; @@ -461,6 +475,11 @@ static int ima_open_data_upload(struct inode *inode, struct file *filp) } if (test_and_set_bit(flag, &ima_fs_flags)) return -EBUSY; + + if (dentry == digest_list_data || dentry == digest_list_data_del) + if (ima_check_current_is_parser()) + ima_set_parser(); + return 0; }

@@ -480,6 +499,9 @@ static int ima_release_data_upload(struct inode *inode, struct file *file) if ((file->f_flags & O_ACCMODE) == O_RDONLY) return seq_release(inode, file);

+ if (dentry == digest_list_data || dentry == digest_list_data_del) + ima_unset_parser(); + if (dentry != ima_policy) { clear_bit(flag, &ima_fs_flags); return 0; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 875dbd5d3de9..cac1362bec86 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -584,18 +584,18 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot) */ int ima_bprm_check(struct linux_binprm *bprm) { - int ret; - u32 secid; - - security_current_getsecid_subj(&secid); - ret = process_measurement(bprm->file, current_cred(), secid, NULL, 0, - MAY_EXEC, BPRM_CHECK); - if (ret) - return ret; - - security_cred_getsecid(bprm->cred, &secid); - return process_measurement(bprm->file, bprm->cred, secid, NULL, 0, - MAY_EXEC, CREDS_CHECK); + int ret; + u32 secid; + + security_current_getsecid_subj(&secid); + ret = process_measurement(bprm->file, current_cred(), secid, NULL, 0, + MAY_EXEC, BPRM_CHECK); + if (ret) + return ret; + + security_cred_getsecid(bprm->cred, &secid); + return process_measurement(bprm->file, bprm->cred, secid, NULL, 0, + MAY_EXEC, CREDS_CHECK); }

/** @@ -610,12 +610,18 @@ int ima_bprm_check(struct linux_binprm *bprm) */ int ima_file_check(struct file *file, int mask) { - u32 secid; + int ret; + u32 secid; + int rc; + + security_current_getsecid_subj(&secid); + rc = process_measurement(file, current_cred(), secid, NULL, 0, + mask & (MAY_READ | MAY_WRITE | MAY_EXEC | + MAY_APPEND), FILE_CHECK); + if (ima_current_is_parser() && !rc) + ima_check_measured_appraised(file); + return rc;

- security_current_getsecid_subj(&secid); - return process_measurement(file, current_cred(), secid, NULL, 0, - mask & (MAY_READ | MAY_WRITE | MAY_EXEC | - MAY_APPEND), FILE_CHECK); } EXPORT_SYMBOL_GPL(ima_file_check);

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Introduce three new values for evm= kernel option:

x509: enable EVM by setting x509 flag; allow_metadata_writes: permit metadata modificatons; complete: don't allow further changes of the EVM status.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- Documentation/admin-guide/kernel-parameters.txt | 10 +++++++--- security/integrity/evm/evm_main.c | 10 ++++++++-- 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 5d84000d344d..e92e899ae964 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1476,9 +1476,13 @@ has equivalent usage. See its documentation for details.

evm= [EVM] - Format: { "fix" } - Permit 'security.evm' to be updated regardless of - current integrity status. + Format: { "fix" | "x509" | "allow_metadata_writes" | + "complete" } + fix: permit 'security.evm' to be updated regardless of + current integrity status; + x509: enable EVM by setting x509 flag; + allow_metadata_writes: permit metadata modificatons; + complete: don't allow further changes of the EVM status.

early_page_ext [KNL] Enforces page_ext initialization to earlier stages so cover more early boot allocations. diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index c681838a0b66..842fe18ad58e 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -73,16 +73,22 @@ static struct xattr_list evm_config_default_xattrnames[] = { LIST_HEAD(evm_config_xattrnames);

static int evm_fixmode __ro_after_init; -static int __init evm_set_fixmode(char *str) +static int __init evm_set_param(char *str) { if (strncmp(str, "fix", 3) == 0) evm_fixmode = 1; + else if (strncmp(str, "x509", 4) == 0) + evm_initialized |= EVM_INIT_X509; + else if (strncmp(str, "allow_metadata_writes", 21) == 0) + evm_initialized |= EVM_ALLOW_METADATA_WRITES; + else if (strncmp(str, "complete", 8) == 0) + evm_initialized |= EVM_SETUP_COMPLETE; else pr_err("invalid "%s" mode", str);

return 1; } -__setup("evm=", evm_set_fixmode); +__setup("evm=", evm_set_param);

static void __init evm_init_config(void) {

From: Roberto Sassu roberto.sassu@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

-------------------------------------------------

Commit 5feeb61183dd ("evm: Allow non-SHA1 digital signatures") introduced the possibility to use different hash algorithm for signatures, but kept the algorithm for the HMAC hard-coded (SHA1). Switching to a different algorithm for HMAC would require to change the code in different places.

This patch introduces a new global variable called evm_hash_algo, and consistently uses it whenever EVM perform HMAC-related operations. It also introduces a new kernel configuration option called CONFIG_EVM_DEFAULT_HASH so that evm_hash_algo can be defined at kernel compilation time.

Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Acked-by: Hanjun Guo guohanjun@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Tianxing Zhang zhangtianxing3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/evm/Kconfig | 32 +++++++++++++++++++++++++++++ security/integrity/evm/evm.h | 1 + security/integrity/evm/evm_crypto.c | 15 +++++++++----- security/integrity/evm/evm_main.c | 15 +++++++++----- security/integrity/integrity.h | 2 +- 5 files changed, 54 insertions(+), 11 deletions(-)

diff --git a/security/integrity/evm/Kconfig b/security/integrity/evm/Kconfig index a6e19d23e700..844f2686cce7 100644 --- a/security/integrity/evm/Kconfig +++ b/security/integrity/evm/Kconfig @@ -13,6 +13,38 @@ config EVM

If you are unsure how to answer this question, answer N.

+choice + prompt "Default EVM hash algorithm" + default EVM_DEFAULT_HASH_SHA256 + depends on EVM + help + Select the default hash algorithm used for the HMAC. + + config EVM_DEFAULT_HASH_SHA1 + bool "SHA1 (default)" + depends on CRYPTO_SHA1=y + + config EVM_DEFAULT_HASH_SHA256 + bool "SHA256" + depends on CRYPTO_SHA256=y + + config EVM_DEFAULT_HASH_SHA512 + bool "SHA512" + depends on CRYPTO_SHA512=y + + config EVM_DEFAULT_HASH_WP512 + bool "WP512" + depends on CRYPTO_WP512=y +endchoice + +config EVM_DEFAULT_HASH + string + depends on EVM + default "sha1" if EVM_DEFAULT_HASH_SHA1 + default "sha256" if EVM_DEFAULT_HASH_SHA256 + default "sha512" if EVM_DEFAULT_HASH_SHA512 + default "wp512" if EVM_DEFAULT_HASH_WP512 + config EVM_ATTR_FSUUID bool "FSUUID (version 2)" default y diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h index f8b8c5004fc7..72776e20c0a8 100644 --- a/security/integrity/evm/evm.h +++ b/security/integrity/evm/evm.h @@ -33,6 +33,7 @@ struct xattr_list { };

extern int evm_initialized; +extern enum hash_algo evm_hash_algo;

#define EVM_ATTR_FSUUID 0x0001

diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c index 259c7c98bb35..a6215dbe50b1 100644 --- a/security/integrity/evm/evm_crypto.c +++ b/security/integrity/evm/evm_crypto.c @@ -35,7 +35,7 @@ static DEFINE_MUTEX(mutex);

static unsigned long evm_set_key_flags;

-static const char evm_hmac[] = "hmac(sha1)"; +enum hash_algo evm_hash_algo __ro_after_init = HASH_ALGO_SHA1;

/** * evm_set_key() - set EVM HMAC key from the kernel @@ -76,8 +76,12 @@ static struct shash_desc *init_desc(char type, uint8_t hash_algo) long rc; const char *algo; struct crypto_shash **tfm, *tmp_tfm; + char evm_hmac[CRYPTO_MAX_ALG_NAME]; struct shash_desc *desc;

+ snprintf(evm_hmac, sizeof(evm_hmac), "hmac(%s)", + CONFIG_EVM_DEFAULT_HASH); + if (type == EVM_XATTR_HMAC) { if (!(evm_initialized & EVM_INIT_HMAC)) { pr_err_once("HMAC key is not set\n"); @@ -373,7 +377,7 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name, if (rc) return -EPERM;

- data.hdr.algo = HASH_ALGO_SHA1; + data.hdr.algo = evm_hash_algo; rc = evm_calc_hmac(dentry, xattr_name, xattr_value, xattr_value_len, &data); if (rc == 0) { @@ -381,7 +385,8 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name, rc = __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_EVM, &data.hdr.xattr.data[1], - SHA1_DIGEST_SIZE + 1, 0); + hash_digest_size[evm_hash_algo] + 1, + 0); } else if (rc == -ENODATA && (inode->i_opflags & IOP_XATTR)) { rc = __vfs_removexattr(&nop_mnt_idmap, dentry, XATTR_NAME_EVM); } @@ -393,7 +398,7 @@ int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr, { struct shash_desc *desc;

- desc = init_desc(EVM_XATTR_HMAC, HASH_ALGO_SHA1); + desc = init_desc(EVM_XATTR_HMAC, evm_hash_algo); if (IS_ERR(desc)) { pr_info("init_desc failed\n"); return PTR_ERR(desc); @@ -406,7 +411,7 @@ int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr, }

/* - * Get the key from the TPM for the SHA1-HMAC + * Get the key from the TPM for the HMAC */ int evm_init_key(void) { diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 842fe18ad58e..305afa22ab9c 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -231,18 +231,18 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry, /* check value type */ switch (xattr_data->type) { case EVM_XATTR_HMAC: - if (xattr_len != sizeof(struct evm_xattr)) { + if (xattr_len != hash_digest_size[evm_hash_algo] + 1) { evm_status = INTEGRITY_FAIL; goto out; }

- digest.hdr.algo = HASH_ALGO_SHA1; + digest.hdr.algo = evm_hash_algo; rc = evm_calc_hmac(dentry, xattr_name, xattr_value, xattr_value_len, &digest); if (rc) break; rc = crypto_memneq(xattr_data->data, digest.digest, - SHA1_DIGEST_SIZE); + hash_digest_size[evm_hash_algo]); if (rc) rc = -EINVAL; break; @@ -955,7 +955,7 @@ int evm_inode_init_security(struct inode *inode, goto out;

evm_xattr->value = xattr_data; - evm_xattr->value_len = sizeof(*xattr_data); + evm_xattr->value_len = hash_digest_size[evm_hash_algo] + 1; evm_xattr->name = XATTR_EVM_SUFFIX; return 0; out: @@ -977,9 +977,14 @@ void __init evm_load_x509(void)

static int __init init_evm(void) { - int error; + int error, i; struct list_head *pos, *q;

+ i = match_string(hash_algo_name, HASH_ALGO__LAST, + CONFIG_EVM_DEFAULT_HASH); + if (i >= 0) + evm_hash_algo = i; + evm_init_config();

error = integrity_init_keyring(INTEGRITY_KEYRING_EVM); diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index a93ad2bcd809..4f0167052b26 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -96,7 +96,7 @@ struct evm_ima_xattr_data { /* Only used in the EVM HMAC code. */ struct evm_xattr { struct evm_ima_xattr_data data; - u8 digest[SHA1_DIGEST_SIZE]; + u8 digest[SHA512_DIGEST_SIZE]; } __packed;

#define IMA_MAX_DIGEST_SIZE HASH_MAX_DIGESTSIZE

From: Zheng Zengkai zhengzengkai@huawei.com

hulk inclusion category: feature feature: IMA Digest Lists extension bugzilla: 46797

---------------------------

This reverts commit 9b772f4948fa513c501ae37c7afc89aa8613314c. backport patch from LTS 5.10.50 instead.

Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- Documentation/ABI/testing/evm | 4 ++-- security/integrity/evm/evm_secfs.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/Documentation/ABI/testing/evm b/Documentation/ABI/testing/evm index 44750a933db4..2828e720d91e 100644 --- a/Documentation/ABI/testing/evm +++ b/Documentation/ABI/testing/evm @@ -69,8 +69,8 @@ Description:

and the resulting value will be 3.

- Note that once an HMAC key has been loaded, it will no longer - be possible to enable metadata modification. Signaling that an + Note that once a key has been loaded, it will no longer be + possible to enable metadata modification. Signaling that an HMAC key has been loaded will clear the corresponding flag. For example, if the current value is 6 (2 and 4 set)::

diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c index 9b907c2fee60..5a762ac6411d 100644 --- a/security/integrity/evm/evm_secfs.c +++ b/security/integrity/evm/evm_secfs.c @@ -86,7 +86,7 @@ static ssize_t evm_write_key(struct file *file, const char __user *buf, * an HMAC key is loaded. */ if ((i & EVM_ALLOW_METADATA_WRITES) && - (evm_initialized & EVM_INIT_HMAC) != 0) + ((evm_initialized & EVM_KEY_MASK) != 0)) return -EPERM;

if (i & EVM_INIT_HMAC) {

From: Zhang Tianxing zhangtianxing3@huawei.com

hulk inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I409K9 CVE: NA

-----------------------------------------------------------------

This patch sets max size for IMA digest database to prevent OOM.

A __ro_after_init global variable ima_digest_db_max_size is used to set the maximum data uploaded to digest database.

Another global variable ima_digest_db_size records the data uploaded to kernel digest database and increments when uploading digest lists.

Signed-off-by: Zhang Tianxing zhangtianxing3@huawei.com Reviewed-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- .../admin-guide/kernel-parameters.txt | 4 +++ arch/arm64/configs/openeuler_defconfig | 5 ++++ arch/x86/configs/openeuler_defconfig | 5 ++++ security/integrity/ima/Kconfig | 27 +++++++++++++++++++ security/integrity/ima/ima.h | 4 +++ security/integrity/ima/ima_digest_list.c | 23 ++++++++++++++++ security/integrity/ima/ima_fs.c | 11 ++++++++ 7 files changed, 79 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index e92e899ae964..4a0261de0ed8 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1975,6 +1975,10 @@ with PCR 10, according to the existing behavior. Format: { [+]<unsigned int> }

+ ima_digest_db_size=nn[M] + [IMA] + Sets the maximum data uploaded to IMA digest database. + ima_hash= [IMA] Format: { md5 | sha1 | rmd160 | sha256 | sha384 | sha512 | ... } diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index 1cb5960fa52f..168a101cb64a 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -7005,6 +7005,11 @@ CONFIG_IMA_X509_PATH="/etc/keys/x509_ima.der" # CONFIG_IMA_APPRAISE_SIGNED_INIT is not set CONFIG_IMA_DIGEST_LIST=y CONFIG_IMA_DIGEST_LISTS_DIR="/etc/ima/digest_lists" +# CONFIG_IMA_MIN_DIGEST_DB_SIZE is not set +CONFIG_IMA_STANDARD_DIGEST_DB_SIZE=y +# CONFIG_IMA_MAX_DIGEST_DB_SIZE is not set +# CONFIG_IMA_CUSTOM_DIGEST_DB_SIZE is not set +CONFIG_IMA_DIGEST_DB_SIZE=16 CONFIG_IMA_PARSER_BINARY_PATH="/usr/bin/upload_digest_lists" CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS=y CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS=y diff --git a/arch/x86/configs/openeuler_defconfig b/arch/x86/configs/openeuler_defconfig index fac5531742a4..599b8fac2c4b 100644 --- a/arch/x86/configs/openeuler_defconfig +++ b/arch/x86/configs/openeuler_defconfig @@ -8251,6 +8251,11 @@ CONFIG_IMA_X509_PATH="/etc/keys/x509_ima.der" # CONFIG_IMA_APPRAISE_SIGNED_INIT is not set CONFIG_IMA_DIGEST_LIST=y CONFIG_IMA_DIGEST_LISTS_DIR="/etc/ima/digest_lists" +# CONFIG_IMA_MIN_DIGEST_DB_SIZE is not set +CONFIG_IMA_STANDARD_DIGEST_DB_SIZE=y +# CONFIG_IMA_MAX_DIGEST_DB_SIZE is not set +# CONFIG_IMA_CUSTOM_DIGEST_DB_SIZE is not set +CONFIG_IMA_DIGEST_DB_SIZE=16 CONFIG_IMA_PARSER_BINARY_PATH="/usr/bin/upload_digest_lists" CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS=y CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS=y diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index aa6a06f3e8b1..eab73b839c2a 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -357,6 +357,33 @@ config IMA_DIGEST_LISTS_DIR This option defines the path of the directory containing digest lists.

+choice + prompt "Defalut maximum data uploaded to the IMA digest database" + default IMA_STANDARD_DIGEST_DB_SIZE + depends on IMA_DIGEST_LIST + help + This option defines the maximum data uploaded to the IMA digest + database. The compiled default limit can be overwritten using the + kernel command line "ima_digest_db_size". + + config IMA_MIN_DIGEST_DB_SIZE + bool "minimum" + config IMA_STANDARD_DIGEST_DB_SIZE + bool "standard (default)" + config IMA_MAX_DIGEST_DB_SIZE + bool "maximum" + config IMA_CUSTOM_DIGEST_DB_SIZE + bool "custom" +endchoice + +config IMA_DIGEST_DB_MEGABYTES + int + depends on IMA_DIGEST_LIST + range 8 64 + default 8 if IMA_MIN_DIGEST_DB_SIZE + default 16 if IMA_STANDARD_DIGEST_DB_SIZE + default 64 if IMA_MAX_DIGEST_DB_SIZE + config IMA_PARSER_BINARY_PATH string "Path of the parser binary" depends on IMA_DIGEST_LIST diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 124b4e78a784..d19d322309fb 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -60,6 +60,10 @@ extern int ima_digest_list_pcr; extern bool ima_plus_standard_pcr; extern const char boot_aggregate_name[]; extern int ima_digest_list_actions; +#ifdef CONFIG_IMA_DIGEST_LIST +extern size_t ima_digest_db_max_size __ro_after_init; +extern size_t ima_digest_db_size; +#endif

/* IMA event related data */ struct ima_event_data { diff --git a/security/integrity/ima/ima_digest_list.c b/security/integrity/ima/ima_digest_list.c index 5aaea24571d9..021ffda4a6f9 100644 --- a/security/integrity/ima/ima_digest_list.c +++ b/security/integrity/ima/ima_digest_list.c @@ -14,6 +14,9 @@ */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#define MIN_DB_SIZE (8 * 1024 * 1024) +#define MAX_DB_SIZE (64 * 1024 * 1024) +#define DEFAULT_DB_SIZE (CONFIG_IMA_DIGEST_DB_MEGABYTES * 1024 * 1024)

#include <linux/vmalloc.h> #include <linux/module.h> @@ -26,11 +29,31 @@ #include "ima.h" #include "ima_digest_list.h"

+size_t ima_digest_db_max_size __ro_after_init = DEFAULT_DB_SIZE; +size_t ima_digest_db_size; + struct ima_h_table ima_digests_htable = { .len = ATOMIC_LONG_INIT(0), .queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT };

+static int __init digest_db_max_size_setup(char *str) +{ + int size; + char *retptr; + + size = memparse(str, &retptr); + if (size < MIN_DB_SIZE || size > MAX_DB_SIZE || *retptr != '\0') { + pr_err("DB size should range from 8M to 64M\n"); + return 0; + } + + ima_digest_db_max_size = size; + + return 1; +} +__setup("ima_digest_db_size=", digest_db_max_size_setup); + static int __init digest_list_pcr_setup(char *str) { int pcr, ret; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 7310683a7af7..66574a79ac97 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -319,6 +319,12 @@ static ssize_t ima_read_file(char *path, struct dentry *dentry) rc = ima_parse_add_rule(p); } else if (dentry == digest_list_data || dentry == digest_list_data_del) { + /* Only check size when adding digest lists */ + if (dentry == digest_list_data && + size > ima_digest_db_max_size - ima_digest_db_size) { + rc = -ENOMEM; + break; + } /* * Disable usage of digest lists if not measured * or appraised. @@ -334,6 +340,11 @@ static ssize_t ima_read_file(char *path, struct dentry *dentry) if (rc < 0) break; size -= rc; + + if (dentry == digest_list_data) + ima_digest_db_size += rc; + if (dentry == digest_list_data_del) + ima_digest_db_size -= rc; }

vfree(data);

From: Zhang Tianxing zhangtianxing3@huawei.com

hulk inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I409K9 CVE: NA

-----------------------------------------------------------------

Commit 7c9d18bcaa ("ima: Add max size for IMA digest database") adds a new Kconfig for IMA Digest Lists: CONFIG_IMA_DIGEST_DB_MEGABYTES. However, that commit has typos in openeuler_defconfig. This patch is to fix that typo.

Fixes: 7c9d18bcaa ("ima: Add max size for IMA digest database") Signed-off-by: Zhang Tianxing zhangtianxing3@huawei.com Reviewed-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- arch/arm64/configs/openeuler_defconfig | 2 +- arch/x86/configs/openeuler_defconfig | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/configs/openeuler_defconfig b/arch/arm64/configs/openeuler_defconfig index 168a101cb64a..f7673afcd6a0 100644 --- a/arch/arm64/configs/openeuler_defconfig +++ b/arch/arm64/configs/openeuler_defconfig @@ -7009,7 +7009,7 @@ CONFIG_IMA_DIGEST_LISTS_DIR="/etc/ima/digest_lists" CONFIG_IMA_STANDARD_DIGEST_DB_SIZE=y # CONFIG_IMA_MAX_DIGEST_DB_SIZE is not set # CONFIG_IMA_CUSTOM_DIGEST_DB_SIZE is not set -CONFIG_IMA_DIGEST_DB_SIZE=16 +CONFIG_IMA_DIGEST_DB_MEGABYTES=16 CONFIG_IMA_PARSER_BINARY_PATH="/usr/bin/upload_digest_lists" CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS=y CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS=y diff --git a/arch/x86/configs/openeuler_defconfig b/arch/x86/configs/openeuler_defconfig index 599b8fac2c4b..2694e416aed5 100644 --- a/arch/x86/configs/openeuler_defconfig +++ b/arch/x86/configs/openeuler_defconfig @@ -8255,7 +8255,7 @@ CONFIG_IMA_DIGEST_LISTS_DIR="/etc/ima/digest_lists" CONFIG_IMA_STANDARD_DIGEST_DB_SIZE=y # CONFIG_IMA_MAX_DIGEST_DB_SIZE is not set # CONFIG_IMA_CUSTOM_DIGEST_DB_SIZE is not set -CONFIG_IMA_DIGEST_DB_SIZE=16 +CONFIG_IMA_DIGEST_DB_MEGABYTES=16 CONFIG_IMA_PARSER_BINARY_PATH="/usr/bin/upload_digest_lists" CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS=y CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS=y

From: shenxiangwei shenxiangwei1@huawei.com

hulk inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4XHBM CVE: NA

-------------

The check for control character shouldn't be added when import a binary digest list.

Signed-off-by: shenxiangwei shenxiangwei1@huawei.com Reviewed-by: Lu Huaxin luhuaxin1@huawei.com Reviewed-by: Roberto Sassu roberto.sassu@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: Zhou Shuiqingzhoushuiqing2@huawei.com --- security/integrity/ima/ima_fs.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 917df82b6b39..e8856d63df7b 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -389,19 +389,21 @@ static ssize_t ima_write_data(struct file *file, const char __user *buf, goto out_free;

data[datalen] = '\0'; - for (i = 0; data[i] != '\n' && data[i] != '\0'; i++) { - if (iscntrl(data[i])) { - pr_err_once("invalid path (control characters are not allowed)\n"); - result = -EINVAL; - goto out_free; - } - }

result = mutex_lock_interruptible(&ima_write_mutex); if (result < 0) goto out_free;

if (data[0] == '/') { + for (i = 0; data[i] != '\n' && data[i] != '\0'; i++) { + if (iscntrl(data[i])) { + pr_err_once("invalid path (control characters are not allowed)\n"); + result = -EINVAL; + mutex_unlock(&ima_write_mutex); + goto out_free; + } + } + result = ima_read_file(data, dentry); } else if (dentry == ima_policy) { if (ima_appraise & IMA_APPRAISE_POLICY) {