diff options
Diffstat (limited to 'security/integrity/ima/ima_main.c')
| -rw-r--r-- | security/integrity/ima/ima_main.c | 69 |
1 files changed, 57 insertions, 12 deletions
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 2cfb0c714967..74d0bd7e76d7 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -16,6 +16,9 @@ * implements the IMA hooks: ima_bprm_check, ima_file_mmap, * and ima_file_check. */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/module.h> #include <linux/file.h> #include <linux/binfmts.h> @@ -25,6 +28,7 @@ #include <linux/xattr.h> #include <linux/ima.h> #include <linux/iversion.h> +#include <linux/fs.h> #include "ima.h" @@ -167,8 +171,9 @@ void ima_file_free(struct file *file) ima_check_last_writer(iint, inode, file); } -static int process_measurement(struct file *file, char *buf, loff_t size, - int mask, enum ima_hooks func, int opened) +static int process_measurement(struct file *file, const struct cred *cred, + u32 secid, char *buf, loff_t size, int mask, + enum ima_hooks func, int opened) { struct inode *inode = file_inode(file); struct integrity_iint_cache *iint = NULL; @@ -190,7 +195,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size, * bitmask based on the appraise/audit/measurement policy. * Included is the appraise submask. */ - action = ima_get_action(inode, mask, func, &pcr); + action = ima_get_action(inode, cred, secid, mask, func, &pcr); violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) && (ima_policy_flag & IMA_MEASURE)); if (!action && !violation_check) @@ -229,9 +234,18 @@ static int process_measurement(struct file *file, char *buf, loff_t size, IMA_APPRAISE_SUBMASK | IMA_APPRAISED_SUBMASK | IMA_ACTION_FLAGS); - if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags)) - /* reset all flags if ima_inode_setxattr was called */ + /* + * Re-evaulate the file if either the xattr has changed or the + * kernel has no way of detecting file change on the filesystem. + * (Limited to privileged mounted filesystems.) + */ + if (test_and_clear_bit(IMA_CHANGE_XATTR, &iint->atomic_flags) || + ((inode->i_sb->s_iflags & SB_I_IMA_UNVERIFIABLE_SIGNATURE) && + !(inode->i_sb->s_iflags & SB_I_UNTRUSTED_MOUNTER) && + !(action & IMA_FAIL_UNVERIFIABLE_SIGS))) { iint->flags &= ~IMA_DONE_MASK; + iint->measured_pcrs = 0; + } /* Determine if already appraised/measured based on bitmask * (IMA_MEASURE, IMA_MEASURED, IMA_XXXX_APPRAISE, IMA_XXXX_APPRAISED, @@ -324,9 +338,14 @@ out: */ int ima_file_mmap(struct file *file, unsigned long prot) { - if (file && (prot & PROT_EXEC)) - return process_measurement(file, NULL, 0, MAY_EXEC, - MMAP_CHECK, 0); + u32 secid; + + if (file && (prot & PROT_EXEC)) { + security_task_getsecid(current, &secid); + return process_measurement(file, current_cred(), secid, NULL, + 0, MAY_EXEC, MMAP_CHECK, 0); + } + return 0; } @@ -345,8 +364,18 @@ int ima_file_mmap(struct file *file, unsigned long prot) */ int ima_bprm_check(struct linux_binprm *bprm) { - return process_measurement(bprm->file, NULL, 0, MAY_EXEC, - BPRM_CHECK, 0); + int ret; + u32 secid; + + security_task_getsecid(current, &secid); + ret = process_measurement(bprm->file, current_cred(), secid, NULL, 0, + MAY_EXEC, BPRM_CHECK, 0); + if (ret) + return ret; + + security_cred_getsecid(bprm->cred, &secid); + return process_measurement(bprm->file, bprm->cred, secid, NULL, 0, + MAY_EXEC, CREDS_CHECK, 0); } /** @@ -361,7 +390,10 @@ int ima_bprm_check(struct linux_binprm *bprm) */ int ima_file_check(struct file *file, int mask, int opened) { - return process_measurement(file, NULL, 0, + u32 secid; + + security_task_getsecid(current, &secid); + return process_measurement(file, current_cred(), secid, NULL, 0, mask & (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND), FILE_CHECK, opened); } @@ -440,6 +472,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, enum kernel_read_file_id read_id) { enum ima_hooks func; + u32 secid; if (!file && read_id == READING_FIRMWARE) { if ((ima_appraise & IMA_APPRAISE_FIRMWARE) && @@ -462,7 +495,9 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, } func = read_idmap[read_id] ?: FILE_CHECK; - return process_measurement(file, buf, size, MAY_READ, func, 0); + security_task_getsecid(current, &secid); + return process_measurement(file, current_cred(), secid, buf, size, + MAY_READ, func, 0); } static int __init init_ima(void) @@ -472,6 +507,16 @@ static int __init init_ima(void) ima_init_template_list(); hash_setup(CONFIG_IMA_DEFAULT_HASH); error = ima_init(); + + if (error && strcmp(hash_algo_name[ima_hash_algo], + CONFIG_IMA_DEFAULT_HASH) != 0) { + pr_info("Allocating %s failed, going to use default hash algorithm %s\n", + hash_algo_name[ima_hash_algo], CONFIG_IMA_DEFAULT_HASH); + hash_setup_done = 0; + hash_setup(CONFIG_IMA_DEFAULT_HASH); + error = ima_init(); + } + if (!error) { ima_initialized = 1; ima_update_policy_flag(); |