diff options
Diffstat (limited to 'security/integrity')
-rw-r--r-- | security/integrity/digsig_asymmetric.c | 11 | ||||
-rw-r--r-- | security/integrity/ima/ima.h | 29 | ||||
-rw-r--r-- | security/integrity/ima/ima_api.c | 12 | ||||
-rw-r--r-- | security/integrity/ima/ima_appraise.c | 45 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 11 | ||||
-rw-r--r-- | security/integrity/integrity.h | 11 |
6 files changed, 94 insertions, 25 deletions
diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c index b475466..9eae480 100644 --- a/security/integrity/digsig_asymmetric.c +++ b/security/integrity/digsig_asymmetric.c @@ -20,17 +20,6 @@ #include "integrity.h" /* - * signature format v2 - for using with asymmetric keys - */ -struct signature_v2_hdr { - uint8_t version; /* signature format version */ - uint8_t hash_algo; /* Digest algorithm [enum pkey_hash_algo] */ - uint32_t keyid; /* IMA key identifier - not X509/PGP specific*/ - uint16_t sig_size; /* signature size */ - uint8_t sig[0]; /* signature payload */ -} __packed; - -/* * Request an asymmetric key. */ static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index eb86032..efcdef2 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -99,7 +99,9 @@ static inline unsigned long ima_hash_key(u8 *digest) int ima_get_action(struct inode *inode, int mask, int function); int ima_must_measure(struct inode *inode, int mask, int function); int ima_collect_measurement(struct integrity_iint_cache *iint, - struct file *file); + struct file *file, + struct evm_ima_xattr_data **xattr_value, + int *xattr_len); void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, const unsigned char *filename); void ima_audit_measurement(struct integrity_iint_cache *iint, @@ -132,17 +134,25 @@ void ima_delete_rules(void); #ifdef CONFIG_IMA_APPRAISE int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename); + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len); int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, int func); +void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_digest_data *hash); +int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value); #else static inline int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, struct file *file, - const unsigned char *filename) + const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len) { return INTEGRITY_UNKNOWN; } @@ -163,6 +173,19 @@ static inline enum integrity_status ima_get_cache_status(struct integrity_iint_c { return INTEGRITY_UNKNOWN; } + +static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, + int xattr_len, + struct ima_digest_data *hash) +{ +} + +static inline int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value) +{ + return 0; +} + #endif /* LSM based policy rules require audit */ diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index e531fe2..1dba98e 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -139,17 +139,27 @@ int ima_must_measure(struct inode *inode, int mask, int function) * Return 0 on success, error code otherwise */ int ima_collect_measurement(struct integrity_iint_cache *iint, - struct file *file) + struct file *file, + struct evm_ima_xattr_data **xattr_value, + int *xattr_len) { struct inode *inode = file_inode(file); const char *filename = file->f_dentry->d_name.name; int result = 0; + if (xattr_value) + *xattr_len = ima_read_xattr(file->f_dentry, xattr_value); + if (!(iint->flags & IMA_COLLECTED)) { u64 i_version = file_inode(file)->i_version; /* use default hash algorithm */ iint->ima_hash.algo = ima_hash_algo; + + if (xattr_value) + ima_get_hash_algo(*xattr_value, *xattr_len, + &iint->ima_hash); + result = ima_calc_file_hash(file, &iint->ima_hash); if (!result) { iint->version = i_version; diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 3833b0fa..00708a3 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -107,6 +107,34 @@ static void ima_cache_flags(struct integrity_iint_cache *iint, int func) } } +void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, + struct ima_digest_data *hash) +{ + struct signature_v2_hdr *sig; + + if (!xattr_value || xattr_len < 0 || xattr_len <= 1 + sizeof(*sig)) + return; + + sig = (typeof(sig)) xattr_value->digest; + + if (xattr_value->type != EVM_IMA_XATTR_DIGSIG || sig->version != 2) + return; + + hash->algo = sig->hash_algo; +} + +int ima_read_xattr(struct dentry *dentry, + struct evm_ima_xattr_data **xattr_value) +{ + struct inode *inode = dentry->d_inode; + + if (!inode->i_op->getxattr) + return 0; + + return vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value, + 0, GFP_NOFS); +} + /* * ima_appraise_measurement - appraise file measurement * @@ -116,23 +144,22 @@ static void ima_cache_flags(struct integrity_iint_cache *iint, int func) * Return 0 on success, error code otherwise */ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename) + struct file *file, const unsigned char *filename, + struct evm_ima_xattr_data *xattr_value, + int xattr_len) { struct dentry *dentry = file->f_dentry; struct inode *inode = dentry->d_inode; - struct evm_ima_xattr_data *xattr_value = NULL; enum integrity_status status = INTEGRITY_UNKNOWN; const char *op = "appraise_data"; char *cause = "unknown"; - int rc; + int rc = xattr_len; if (!ima_appraise) return 0; if (!inode->i_op->getxattr) return INTEGRITY_UNKNOWN; - rc = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)&xattr_value, - 0, GFP_NOFS); if (rc <= 0) { if (rc && rc != -ENODATA) goto out; @@ -159,7 +186,10 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, status = INTEGRITY_FAIL; break; } - if (rc - 1 == iint->ima_hash.length) + if (xattr_len - 1 >= iint->ima_hash.length) + /* xattr length may be longer. md5 hash in previous + version occupied 20 bytes in xattr, instead of 16 + */ rc = memcmp(xattr_value->digest, iint->ima_hash.digest, iint->ima_hash.length); @@ -207,7 +237,6 @@ out: ima_cache_flags(iint, func); } ima_set_cache_status(iint, func, status); - kfree(xattr_value); return status; } @@ -223,7 +252,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) if (iint->flags & IMA_DIGSIG) return; - rc = ima_collect_measurement(iint, file); + rc = ima_collect_measurement(iint, file, NULL, NULL); if (rc < 0) return; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 7708c21..95b5df2 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -149,6 +149,8 @@ static int process_measurement(struct file *file, const char *filename, char *pathbuf = NULL; const char *pathname = NULL; int rc = -ENOMEM, action, must_appraise, _func; + struct evm_ima_xattr_data *xattr_value = NULL, **xattr_ptr = NULL; + int xattr_len = 0; if (!ima_initialized || !S_ISREG(inode->i_mode)) return 0; @@ -187,7 +189,10 @@ static int process_measurement(struct file *file, const char *filename, goto out_digsig; } - rc = ima_collect_measurement(iint, file); + if (action & IMA_APPRAISE_SUBMASK) + xattr_ptr = &xattr_value; + + rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len); if (rc != 0) goto out_digsig; @@ -198,7 +203,8 @@ static int process_measurement(struct file *file, const char *filename, if (action & IMA_MEASURE) ima_store_measurement(iint, file, pathname); if (action & IMA_APPRAISE_SUBMASK) - rc = ima_appraise_measurement(_func, iint, file, pathname); + rc = ima_appraise_measurement(_func, iint, file, pathname, + xattr_value, xattr_len); if (action & IMA_AUDIT) ima_audit_measurement(iint, pathname); kfree(pathbuf); @@ -207,6 +213,7 @@ out_digsig: rc = -EACCES; out: mutex_unlock(&inode->i_mutex); + kfree(xattr_value); if ((rc && must_appraise) && (ima_appraise & IMA_APPRAISE_ENFORCE)) return -EACCES; return 0; diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 0b02ea8..ea23189 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -70,6 +70,17 @@ struct ima_digest_data { u8 digest[IMA_MAX_DIGEST_SIZE]; } __packed; +/* + * signature format v2 - for using with asymmetric keys + */ +struct signature_v2_hdr { + uint8_t version; /* signature format version */ + uint8_t hash_algo; /* Digest algorithm [enum pkey_hash_algo] */ + uint32_t keyid; /* IMA key identifier - not X509/PGP specific */ + uint16_t sig_size; /* signature size */ + uint8_t sig[0]; /* signature payload */ +} __packed; + /* integrity data associated with an inode */ struct integrity_iint_cache { struct rb_node rb_node; /* rooted in integrity_iint_tree */ |