diff options
Diffstat (limited to 'security/integrity/ima')
| -rw-r--r-- | security/integrity/ima/Kconfig | 1 | ||||
| -rw-r--r-- | security/integrity/ima/Makefile | 2 | ||||
| -rw-r--r-- | security/integrity/ima/ima.h | 150 | ||||
| -rw-r--r-- | security/integrity/ima/ima_api.c | 39 | ||||
| -rw-r--r-- | security/integrity/ima/ima_appraise.c | 66 | ||||
| -rw-r--r-- | security/integrity/ima/ima_iint.c | 142 | ||||
| -rw-r--r-- | security/integrity/ima/ima_init.c | 2 | ||||
| -rw-r--r-- | security/integrity/ima/ima_main.c | 148 | ||||
| -rw-r--r-- | security/integrity/ima/ima_policy.c | 17 | ||||
| -rw-r--r-- | security/integrity/ima/ima_template_lib.c | 17 |
10 files changed, 479 insertions, 105 deletions
diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index b98bfe9efd..475c326150 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -8,6 +8,7 @@ config IMA select CRYPTO_HMAC select CRYPTO_SHA1 select CRYPTO_HASH_INFO + select SECURITY_PATH select TCG_TPM if HAS_IOMEM select TCG_TIS if TCG_TPM && X86 select TCG_CRB if TCG_TPM && ACPI diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile index 2499f2485c..b376d38b4e 100644 --- a/security/integrity/ima/Makefile +++ b/security/integrity/ima/Makefile @@ -4,7 +4,7 @@ # Measurement Architecture(IMA). # -obj-$(CONFIG_IMA) += ima.o +obj-$(CONFIG_IMA) += ima.o ima_iint.o ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \ ima_policy.o ima_template.o ima_template_lib.o diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index c29db699c9..0a4f274f77 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -60,7 +60,7 @@ extern const char boot_aggregate_name[]; /* IMA event related data */ struct ima_event_data { - struct integrity_iint_cache *iint; + struct ima_iint_cache *iint; struct file *file; const unsigned char *filename; struct evm_ima_xattr_data *xattr_value; @@ -119,6 +119,107 @@ struct ima_kexec_hdr { u64 count; }; +/* IMA iint action cache flags */ +#define IMA_MEASURE 0x00000001 +#define IMA_MEASURED 0x00000002 +#define IMA_APPRAISE 0x00000004 +#define IMA_APPRAISED 0x00000008 +/*#define IMA_COLLECT 0x00000010 do not use this flag */ +#define IMA_COLLECTED 0x00000020 +#define IMA_AUDIT 0x00000040 +#define IMA_AUDITED 0x00000080 +#define IMA_HASH 0x00000100 +#define IMA_HASHED 0x00000200 + +/* IMA iint policy rule cache flags */ +#define IMA_NONACTION_FLAGS 0xff000000 +#define IMA_DIGSIG_REQUIRED 0x01000000 +#define IMA_PERMIT_DIRECTIO 0x02000000 +#define IMA_NEW_FILE 0x04000000 +#define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000 +#define IMA_MODSIG_ALLOWED 0x20000000 +#define IMA_CHECK_BLACKLIST 0x40000000 +#define IMA_VERITY_REQUIRED 0x80000000 + +#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ + IMA_HASH | IMA_APPRAISE_SUBMASK) +#define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \ + IMA_HASHED | IMA_COLLECTED | \ + IMA_APPRAISED_SUBMASK) + +/* IMA iint subaction appraise cache flags */ +#define IMA_FILE_APPRAISE 0x00001000 +#define IMA_FILE_APPRAISED 0x00002000 +#define IMA_MMAP_APPRAISE 0x00004000 +#define IMA_MMAP_APPRAISED 0x00008000 +#define IMA_BPRM_APPRAISE 0x00010000 +#define IMA_BPRM_APPRAISED 0x00020000 +#define IMA_READ_APPRAISE 0x00040000 +#define IMA_READ_APPRAISED 0x00080000 +#define IMA_CREDS_APPRAISE 0x00100000 +#define IMA_CREDS_APPRAISED 0x00200000 +#define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \ + IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \ + IMA_CREDS_APPRAISE) +#define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \ + IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \ + IMA_CREDS_APPRAISED) + +/* IMA iint cache atomic_flags */ +#define IMA_CHANGE_XATTR 0 +#define IMA_UPDATE_XATTR 1 +#define IMA_CHANGE_ATTR 2 +#define IMA_DIGSIG 3 +#define IMA_MUST_MEASURE 4 + +/* IMA integrity metadata associated with an inode */ +struct ima_iint_cache { + struct mutex mutex; /* protects: version, flags, digest */ + u64 version; /* track inode changes */ + unsigned long flags; + unsigned long measured_pcrs; + unsigned long atomic_flags; + unsigned long real_ino; + dev_t real_dev; + enum integrity_status ima_file_status:4; + enum integrity_status ima_mmap_status:4; + enum integrity_status ima_bprm_status:4; + enum integrity_status ima_read_status:4; + enum integrity_status ima_creds_status:4; + struct ima_digest_data *ima_hash; +}; + +extern struct lsm_blob_sizes ima_blob_sizes; + +static inline struct ima_iint_cache * +ima_inode_get_iint(const struct inode *inode) +{ + struct ima_iint_cache **iint_sec; + + if (unlikely(!inode->i_security)) + return NULL; + + iint_sec = inode->i_security + ima_blob_sizes.lbs_inode; + return *iint_sec; +} + +static inline void ima_inode_set_iint(const struct inode *inode, + struct ima_iint_cache *iint) +{ + struct ima_iint_cache **iint_sec; + + if (unlikely(!inode->i_security)) + return; + + iint_sec = inode->i_security + ima_blob_sizes.lbs_inode; + *iint_sec = iint; +} + +struct ima_iint_cache *ima_iint_find(struct inode *inode); +struct ima_iint_cache *ima_inode_get(struct inode *inode); +void ima_inode_free(struct inode *inode); +void __init ima_iintcache_init(void); + extern const int read_idmap[]; #ifdef CONFIG_HAVE_IMA_KEXEC @@ -127,6 +228,12 @@ void ima_load_kexec_buffer(void); static inline void ima_load_kexec_buffer(void) {} #endif /* CONFIG_HAVE_IMA_KEXEC */ +#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS +void ima_post_key_create_or_update(struct key *keyring, struct key *key, + const void *payload, size_t plen, + unsigned long flags, bool create); +#endif + /* * The default binary_runtime_measurements list format is defined as the * platform native format. The canonical format is defined as little-endian. @@ -146,8 +253,8 @@ int ima_calc_field_array_hash(struct ima_field_data *field_data, struct ima_template_entry *entry); int ima_calc_boot_aggregate(struct ima_digest_data *hash); void ima_add_violation(struct file *file, const unsigned char *filename, - struct integrity_iint_cache *iint, - const char *op, const char *cause); + struct ima_iint_cache *iint, const char *op, + const char *cause); int ima_init_crypto(void); void ima_putc(struct seq_file *m, void *data, int datalen); void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); @@ -261,10 +368,10 @@ int ima_get_action(struct mnt_idmap *idmap, struct inode *inode, struct ima_template_desc **template_desc, const char *func_data, unsigned int *allowed_algos); int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); -int ima_collect_measurement(struct integrity_iint_cache *iint, - struct file *file, void *buf, loff_t size, - enum hash_algo algo, struct modsig *modsig); -void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, +int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file, + void *buf, loff_t size, enum hash_algo algo, + struct modsig *modsig); +void ima_store_measurement(struct ima_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 pcr, @@ -274,7 +381,7 @@ int process_buffer_measurement(struct mnt_idmap *idmap, const char *eventname, enum ima_hooks func, int pcr, const char *func_data, bool buf_hash, u8 *digest, size_t digest_len); -void ima_audit_measurement(struct integrity_iint_cache *iint, +void ima_audit_measurement(struct ima_iint_cache *iint, const unsigned char *filename); int ima_alloc_init_template(struct ima_event_data *event_data, struct ima_template_entry **entry, @@ -312,32 +419,32 @@ int ima_policy_show(struct seq_file *m, void *v); #define IMA_APPRAISE_KEXEC 0x40 #ifdef CONFIG_IMA_APPRAISE -int ima_check_blacklist(struct integrity_iint_cache *iint, +int ima_check_blacklist(struct ima_iint_cache *iint, const struct modsig *modsig, int pcr); -int ima_appraise_measurement(enum ima_hooks func, - struct integrity_iint_cache *iint, +int ima_appraise_measurement(enum ima_hooks func, struct ima_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 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); -enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, +void ima_update_xattr(struct ima_iint_cache *iint, struct file *file); +enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func); enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value, int xattr_len); int ima_read_xattr(struct dentry *dentry, struct evm_ima_xattr_data **xattr_value, int xattr_len); +void __init init_ima_appraise_lsm(const struct lsm_id *lsmid); #else -static inline int ima_check_blacklist(struct integrity_iint_cache *iint, +static inline int ima_check_blacklist(struct ima_iint_cache *iint, const struct modsig *modsig, int pcr) { return 0; } static inline int ima_appraise_measurement(enum ima_hooks func, - struct integrity_iint_cache *iint, + struct ima_iint_cache *iint, struct file *file, const unsigned char *filename, struct evm_ima_xattr_data *xattr_value, @@ -354,14 +461,13 @@ static inline int ima_must_appraise(struct mnt_idmap *idmap, return 0; } -static inline void ima_update_xattr(struct integrity_iint_cache *iint, +static inline void ima_update_xattr(struct ima_iint_cache *iint, struct file *file) { } -static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache - *iint, - enum ima_hooks func) +static inline enum integrity_status +ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func) { return INTEGRITY_UNKNOWN; } @@ -379,6 +485,10 @@ static inline int ima_read_xattr(struct dentry *dentry, return 0; } +static inline void __init init_ima_appraise_lsm(const struct lsm_id *lsmid) +{ +} + #endif /* CONFIG_IMA_APPRAISE */ #ifdef CONFIG_IMA_APPRAISE_MODSIG @@ -430,7 +540,7 @@ static inline void ima_free_modsig(struct modsig *modsig) #else static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, - void **lsmrule) + void **lsmrule, gfp_t gfp) { return -EINVAL; } diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index 597ea0c4d7..1856981e33 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -131,8 +131,8 @@ int ima_store_template(struct ima_template_entry *entry, * value is invalidated. */ void ima_add_violation(struct file *file, const unsigned char *filename, - struct integrity_iint_cache *iint, - const char *op, const char *cause) + struct ima_iint_cache *iint, const char *op, + const char *cause) { struct ima_template_entry *entry; struct inode *inode = file_inode(file); @@ -201,7 +201,8 @@ int ima_get_action(struct mnt_idmap *idmap, struct inode *inode, allowed_algos); } -static bool ima_get_verity_digest(struct integrity_iint_cache *iint, +static bool ima_get_verity_digest(struct ima_iint_cache *iint, + struct inode *inode, struct ima_max_digest_data *hash) { enum hash_algo alg; @@ -211,7 +212,7 @@ static bool ima_get_verity_digest(struct integrity_iint_cache *iint, * On failure, 'measure' policy rules will result in a file data * hash containing 0's. */ - digest_len = fsverity_get_digest(iint->inode, hash->digest, NULL, &alg); + digest_len = fsverity_get_digest(inode, hash->digest, NULL, &alg); if (digest_len == 0) return false; @@ -237,15 +238,15 @@ static bool ima_get_verity_digest(struct integrity_iint_cache *iint, * * Return 0 on success, error code otherwise */ -int ima_collect_measurement(struct integrity_iint_cache *iint, - struct file *file, void *buf, loff_t size, - enum hash_algo algo, struct modsig *modsig) +int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file, + void *buf, loff_t size, enum hash_algo algo, + struct modsig *modsig) { const char *audit_cause = "failed"; struct inode *inode = file_inode(file); struct inode *real_inode = d_real_inode(file_dentry(file)); - const char *filename = file->f_path.dentry->d_name.name; struct ima_max_digest_data hash; + struct name_snapshot filename; struct kstat stat; int result = 0; int length; @@ -280,7 +281,7 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, memset(&hash.digest, 0, sizeof(hash.digest)); if (iint->flags & IMA_VERITY_REQUIRED) { - if (!ima_get_verity_digest(iint, &hash)) { + if (!ima_get_verity_digest(iint, inode, &hash)) { audit_cause = "no-verity-digest"; result = -ENODATA; } @@ -316,9 +317,13 @@ out: if (file->f_flags & O_DIRECT) audit_cause = "failed(directio)"; + take_dentry_name_snapshot(&filename, file->f_path.dentry); + integrity_audit_msg(AUDIT_INTEGRITY_DATA, inode, - filename, "collect_data", audit_cause, - result, 0); + filename.name.name, "collect_data", + audit_cause, result, 0); + + release_dentry_name_snapshot(&filename); } return result; } @@ -338,8 +343,8 @@ out: * * Must be called with iint->mutex held. */ -void ima_store_measurement(struct integrity_iint_cache *iint, - struct file *file, const unsigned char *filename, +void ima_store_measurement(struct ima_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 pcr, struct ima_template_desc *template_desc) @@ -382,7 +387,7 @@ void ima_store_measurement(struct integrity_iint_cache *iint, ima_free_template_entry(entry); } -void ima_audit_measurement(struct integrity_iint_cache *iint, +void ima_audit_measurement(struct ima_iint_cache *iint, const unsigned char *filename) { struct audit_buffer *ab; @@ -431,6 +436,7 @@ out: */ const char *ima_d_path(const struct path *path, char **pathbuf, char *namebuf) { + struct name_snapshot filename; char *pathname = NULL; *pathbuf = __getname(); @@ -444,7 +450,10 @@ const char *ima_d_path(const struct path *path, char **pathbuf, char *namebuf) } if (!pathname) { - strscpy(namebuf, path->dentry->d_name.name, NAME_MAX); + take_dentry_name_snapshot(&filename, path->dentry); + strscpy(namebuf, filename.name.name, NAME_MAX); + release_dentry_name_snapshot(&filename); + pathname = namebuf; } diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 870dde6770..3497741cae 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -84,8 +84,7 @@ int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode, NULL, NULL, NULL); } -static int ima_fix_xattr(struct dentry *dentry, - struct integrity_iint_cache *iint) +static int ima_fix_xattr(struct dentry *dentry, struct ima_iint_cache *iint) { int rc, offset; u8 algo = iint->ima_hash->algo; @@ -106,7 +105,7 @@ static int ima_fix_xattr(struct dentry *dentry, } /* Return specific func appraised cached result */ -enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, +enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func) { switch (func) { @@ -126,7 +125,7 @@ enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, } } -static void ima_set_cache_status(struct integrity_iint_cache *iint, +static void ima_set_cache_status(struct ima_iint_cache *iint, enum ima_hooks func, enum integrity_status status) { @@ -152,8 +151,7 @@ static void ima_set_cache_status(struct integrity_iint_cache *iint, } } -static void ima_cache_flags(struct integrity_iint_cache *iint, - enum ima_hooks func) +static void ima_cache_flags(struct ima_iint_cache *iint, enum ima_hooks func) { switch (func) { case MMAP_CHECK: @@ -276,7 +274,7 @@ static int calc_file_id_hash(enum evm_ima_xattr_type type, * * Return 0 on success, error code otherwise. */ -static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint, +static int xattr_verify(enum ima_hooks func, struct ima_iint_cache *iint, struct evm_ima_xattr_data *xattr_value, int xattr_len, enum integrity_status *status, const char **cause) { @@ -443,7 +441,7 @@ static int modsig_verify(enum ima_hooks func, const struct modsig *modsig, * * Returns -EPERM if the hash is blacklisted. */ -int ima_check_blacklist(struct integrity_iint_cache *iint, +int ima_check_blacklist(struct ima_iint_cache *iint, const struct modsig *modsig, int pcr) { enum hash_algo hash_algo; @@ -477,8 +475,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint, * * Return 0 on success, error code otherwise */ -int ima_appraise_measurement(enum ima_hooks func, - struct integrity_iint_cache *iint, +int ima_appraise_measurement(enum ima_hooks func, struct ima_iint_cache *iint, struct file *file, const unsigned char *filename, struct evm_ima_xattr_data *xattr_value, int xattr_len, const struct modsig *modsig) @@ -520,7 +517,7 @@ int ima_appraise_measurement(enum ima_hooks func, } status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value, - rc < 0 ? 0 : rc, iint); + rc < 0 ? 0 : rc); switch (status) { case INTEGRITY_PASS: case INTEGRITY_PASS_IMMUTABLE: @@ -603,7 +600,7 @@ out: /* * ima_update_xattr - update 'security.ima' hash value */ -void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) +void ima_update_xattr(struct ima_iint_cache *iint, struct file *file) { struct dentry *dentry = file_dentry(file); int rc = 0; @@ -629,17 +626,18 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file) * ima_inode_post_setattr - reflect file metadata changes * @idmap: idmap of the mount the inode was found from * @dentry: pointer to the affected dentry + * @ia_valid: for the UID and GID status * * Changes to a dentry's metadata might result in needing to appraise. * * This function is called from notify_change(), which expects the caller * to lock the inode's i_mutex. */ -void ima_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry) +static void ima_inode_post_setattr(struct mnt_idmap *idmap, + struct dentry *dentry, int ia_valid) { struct inode *inode = d_backing_inode(dentry); - struct integrity_iint_cache *iint; + struct ima_iint_cache *iint; int action; if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode) @@ -647,7 +645,7 @@ void ima_inode_post_setattr(struct mnt_idmap *idmap, return; action = ima_must_appraise(idmap, inode, MAY_ACCESS, POST_SETATTR); - iint = integrity_iint_find(inode); + iint = ima_iint_find(inode); if (iint) { set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags); if (!action) @@ -673,12 +671,12 @@ static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name, static void ima_reset_appraise_flags(struct inode *inode, int digsig) { - struct integrity_iint_cache *iint; + struct ima_iint_cache *iint; if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)) return; - iint = integrity_iint_find(inode); + iint = ima_iint_find(inode); if (!iint) return; iint->measured_pcrs = 0; @@ -749,8 +747,9 @@ static int validate_hash_algo(struct dentry *dentry, return -EACCES; } -int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, - const void *xattr_value, size_t xattr_value_len) +static int ima_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, + const char *xattr_name, const void *xattr_value, + size_t xattr_value_len, int flags) { const struct evm_ima_xattr_data *xvalue = xattr_value; int digsig = 0; @@ -779,8 +778,8 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, return result; } -int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, - const char *acl_name, struct posix_acl *kacl) +static int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, + const char *acl_name, struct posix_acl *kacl) { if (evm_revalidate_status(acl_name)) ima_reset_appraise_flags(d_backing_inode(dentry), 0); @@ -788,7 +787,8 @@ int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, return 0; } -int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name) +static int ima_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, + const char *xattr_name) { int result; @@ -800,3 +800,23 @@ int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name) } return result; } + +static int ima_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, + const char *acl_name) +{ + return ima_inode_set_acl(idmap, dentry, acl_name, NULL); +} + +static struct security_hook_list ima_appraise_hooks[] __ro_after_init = { + LSM_HOOK_INIT(inode_post_setattr, ima_inode_post_setattr), + LSM_HOOK_INIT(inode_setxattr, ima_inode_setxattr), + LSM_HOOK_INIT(inode_set_acl, ima_inode_set_acl), + LSM_HOOK_INIT(inode_removexattr, ima_inode_removexattr), + LSM_HOOK_INIT(inode_remove_acl, ima_inode_remove_acl), +}; + +void __init init_ima_appraise_lsm(const struct lsm_id *lsmid) +{ + security_add_hooks(ima_appraise_hooks, ARRAY_SIZE(ima_appraise_hooks), + lsmid); +} diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c new file mode 100644 index 0000000000..e7c9c216c1 --- /dev/null +++ b/security/integrity/ima/ima_iint.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2008 IBM Corporation + * + * Authors: + * Mimi Zohar <zohar@us.ibm.com> + * + * File: ima_iint.c + * - implements the IMA hook: ima_inode_free + * - cache integrity information in the inode security blob + */ +#include <linux/slab.h> + +#include "ima.h" + +static struct kmem_cache *ima_iint_cache __ro_after_init; + +/** + * ima_iint_find - Return the iint associated with an inode + * @inode: Pointer to the inode + * + * Return the IMA integrity information (iint) associated with an inode, if the + * inode was processed by IMA. + * + * Return: Found iint or NULL. + */ +struct ima_iint_cache *ima_iint_find(struct inode *inode) +{ + if (!IS_IMA(inode)) + return NULL; + + return ima_inode_get_iint(inode); +} + +#define IMA_MAX_NESTING (FILESYSTEM_MAX_STACK_DEPTH + 1) + +/* + * It is not clear that IMA should be nested at all, but as long is it measures + * files both on overlayfs and on underlying fs, we need to annotate the iint + * mutex to avoid lockdep false positives related to IMA + overlayfs. + * See ovl_lockdep_annotate_inode_mutex_key() for more details. + */ +static inline void ima_iint_lockdep_annotate(struct ima_iint_cache *iint, + struct inode *inode) +{ +#ifdef CONFIG_LOCKDEP + static struct lock_class_key ima_iint_mutex_key[IMA_MAX_NESTING]; + + int depth = inode->i_sb->s_stack_depth; + + if (WARN_ON_ONCE(depth < 0 || depth >= IMA_MAX_NESTING)) + depth = 0; + + lockdep_set_class(&iint->mutex, &ima_iint_mutex_key[depth]); +#endif +} + +static void ima_iint_init_always(struct ima_iint_cache *iint, + struct inode *inode) +{ + iint->ima_hash = NULL; + iint->version = 0; + iint->flags = 0UL; + iint->atomic_flags = 0UL; + iint->ima_file_status = INTEGRITY_UNKNOWN; + iint->ima_mmap_status = INTEGRITY_UNKNOWN; + iint->ima_bprm_status = INTEGRITY_UNKNOWN; + iint->ima_read_status = INTEGRITY_UNKNOWN; + iint->ima_creds_status = INTEGRITY_UNKNOWN; + iint->measured_pcrs = 0; + mutex_init(&iint->mutex); + ima_iint_lockdep_annotate(iint, inode); +} + +static void ima_iint_free(struct ima_iint_cache *iint) +{ + kfree(iint->ima_hash); + mutex_destroy(&iint->mutex); + kmem_cache_free(ima_iint_cache, iint); +} + +/** + * ima_inode_get - Find or allocate an iint associated with an inode + * @inode: Pointer to the inode + * + * Find an iint associated with an inode, and allocate a new one if not found. + * Caller must lock i_mutex. + * + * Return: An iint on success, NULL on error. + */ +struct ima_iint_cache *ima_inode_get(struct inode *inode) +{ + struct ima_iint_cache *iint; + + iint = ima_iint_find(inode); + if (iint) + return iint; + + iint = kmem_cache_alloc(ima_iint_cache, GFP_NOFS); + if (!iint) + return NULL; + + ima_iint_init_always(iint, inode); + + inode->i_flags |= S_IMA; + ima_inode_set_iint(inode, iint); + + return iint; +} + +/** + * ima_inode_free - Called on inode free + * @inode: Pointer to the inode + * + * Free the iint associated with an inode. + */ +void ima_inode_free(struct inode *inode) +{ + struct ima_iint_cache *iint; + + if (!IS_IMA(inode)) + return; + + iint = ima_iint_find(inode); + ima_inode_set_iint(inode, NULL); + + ima_iint_free(iint); +} + +static void ima_iint_init_once(void *foo) +{ + struct ima_iint_cache *iint = (struct ima_iint_cache *)foo; + + memset(iint, 0, sizeof(*iint)); +} + +void __init ima_iintcache_init(void) +{ + ima_iint_cache = + kmem_cache_create("ima_iint_cache", sizeof(struct ima_iint_cache), + 0, SLAB_PANIC, ima_iint_init_once); +} diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 63979aefc9..393f5c7912 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -44,7 +44,7 @@ static int __init ima_add_boot_aggregate(void) static const char op[] = "add_boot_aggregate"; const char *audit_cause = "ENOMEM"; struct ima_template_entry *entry; - struct integrity_iint_cache tmp_iint, *iint = &tmp_iint; + struct ima_iint_cache tmp_iint, *iint = &tmp_iint; struct ima_event_data event_data = { .iint = iint, .filename = boot_aggregate_name }; struct ima_max_digest_data hash; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index cc1217ac2c..c84e8c5533 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -114,7 +114,7 @@ static int mmap_violation_check(enum ima_hooks func, struct file *file, * */ static void ima_rdwr_violation_check(struct file *file, - struct integrity_iint_cache *iint, + struct ima_iint_cache *iint, int must_measure, char **pathbuf, const char **pathname, @@ -127,7 +127,7 @@ static void ima_rdwr_violation_check(struct file *file, if (mode & FMODE_WRITE) { if (atomic_read(&inode->i_readcount) && IS_IMA(inode)) { if (!iint) - iint = integrity_iint_find(inode); + iint = ima_iint_find(inode); /* IMA_MEASURE is set from reader side */ if (iint && test_bit(IMA_MUST_MEASURE, &iint->atomic_flags)) @@ -153,7 +153,7 @@ static void ima_rdwr_violation_check(struct file *file, "invalid_pcr", "open_writers"); } -static void ima_check_last_writer(struct integrity_iint_cache *iint, +static void ima_check_last_writer(struct ima_iint_cache *iint, struct inode *inode, struct file *file) { fmode_t mode = file->f_mode; @@ -189,15 +189,15 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint, * * Flag files that changed, based on i_version */ -void ima_file_free(struct file *file) +static void ima_file_free(struct file *file) { struct inode *inode = file_inode(file); - struct integrity_iint_cache *iint; + struct ima_iint_cache *iint; if (!ima_policy_flag || !S_ISREG(inode->i_mode)) return; - iint = integrity_iint_find(inode); + iint = ima_iint_find(inode); if (!iint) return; @@ -209,7 +209,7 @@ static int process_measurement(struct file *file, const struct cred *cred, enum ima_hooks func) { struct inode *backing_inode, *inode = file_inode(file); - struct integrity_iint_cache *iint = NULL; + struct ima_iint_cache *iint = NULL; struct ima_template_desc *template_desc = NULL; char *pathbuf = NULL; char filename[NAME_MAX]; @@ -248,7 +248,7 @@ static int process_measurement(struct file *file, const struct cred *cred, inode_lock(inode); if (action) { - iint = integrity_inode_get(inode); + iint = ima_inode_get(inode); if (!iint) rc = -ENOMEM; } @@ -427,8 +427,8 @@ out: * On success return 0. On integrity appraisal error, assuming the file * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. */ -int ima_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags) +static int ima_file_mmap(struct file *file, unsigned long reqprot, + unsigned long prot, unsigned long flags) { u32 secid; int ret; @@ -455,7 +455,8 @@ int ima_file_mmap(struct file *file, unsigned long reqprot, /** * ima_file_mprotect - based on policy, limit mprotect change * @vma: vm_area_struct protection is set to - * @prot: contains the protection that will be applied by the kernel. + * @reqprot: protection requested by the application + * @prot: protection that will be applied by the kernel * * Files can be mmap'ed read/write and later changed to execute to circumvent * IMA's mmap appraisal policy rules. Due to locking issues (mmap semaphore @@ -465,7 +466,8 @@ int ima_file_mmap(struct file *file, unsigned long reqprot, * * On mprotect change success, return 0. On failure, return -EACESS. */ -int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot) +static int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, + unsigned long prot) { struct ima_template_desc *template = NULL; struct file *file; @@ -523,7 +525,7 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot) * On success return 0. On integrity appraisal error, assuming the file * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. */ -int ima_bprm_check(struct linux_binprm *bprm) +static int ima_bprm_check(struct linux_binprm *bprm) { int ret; u32 secid; @@ -549,7 +551,7 @@ int ima_bprm_check(struct linux_binprm *bprm) * On success return 0. On integrity appraisal error, assuming the file * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. */ -int ima_file_check(struct file *file, int mask) +static int ima_file_check(struct file *file, int mask) { u32 secid; @@ -558,16 +560,15 @@ int ima_file_check(struct file *file, int mask) mask & (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND), FILE_CHECK); } -EXPORT_SYMBOL_GPL(ima_file_check); static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf, size_t buf_size) { - struct integrity_iint_cache *iint = NULL, tmp_iint; + struct ima_iint_cache *iint = NULL, tmp_iint; int rc, hash_algo; if (ima_policy_flag) { - iint = integrity_iint_find(inode); + iint = ima_iint_find(inode); if (iint) mutex_lock(&iint->mutex); } @@ -577,7 +578,6 @@ static int __ima_inode_hash(struct inode *inode, struct file *file, char *buf, mutex_unlock(&iint->mutex); memset(&tmp_iint, 0, sizeof(tmp_iint)); - tmp_iint.inode = inode; mutex_init(&tmp_iint.mutex); rc = ima_collect_measurement(&tmp_iint, file, NULL, 0, @@ -683,10 +683,11 @@ EXPORT_SYMBOL_GPL(ima_inode_hash); * Skip calling process_measurement(), but indicate which newly, created * tmpfiles are in policy. */ -void ima_post_create_tmpfile(struct mnt_idmap *idmap, - struct inode *inode) +static void ima_post_create_tmpfile(struct mnt_idmap *idmap, + struct inode *inode) + { - struct integrity_iint_cache *iint; + struct ima_iint_cache *iint; int must_appraise; if (!ima_policy_flag || !S_ISREG(inode->i_mode)) @@ -698,7 +699,7 @@ void ima_post_create_tmpfile(struct mnt_idmap *idmap, return; /* Nothing to do if we can't allocate memory */ - iint = integrity_inode_get(inode); + iint = ima_inode_get(inode); if (!iint) return; @@ -715,10 +716,9 @@ void ima_post_create_tmpfile(struct mnt_idmap *idmap, * Mark files created via the mknodat syscall as new, so that the * file data can be written later. */ -void ima_post_path_mknod(struct mnt_idmap *idmap, - struct dentry *dentry) +static void ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry) { - struct integrity_iint_cache *iint; + struct ima_iint_cache *iint; struct inode *inode = dentry->d_inode; int must_appraise; @@ -731,7 +731,7 @@ void ima_post_path_mknod(struct mnt_idmap *idmap, return; /* Nothing to do if we can't allocate memory */ - iint = integrity_inode_get(inode); + iint = ima_inode_get(inode); if (!iint) return; @@ -751,8 +751,8 @@ void ima_post_path_mknod(struct mnt_idmap *idmap, * * For permission return 0, otherwise return -EACCES. */ -int ima_read_file(struct file *file, enum kernel_read_file_id read_id, - bool contents) +static int ima_read_file(struct file *file, enum kernel_read_file_id read_id, + bool contents) { enum ima_hooks func; u32 secid; @@ -801,8 +801,8 @@ const int read_idmap[READING_MAX_ID] = { * On success return 0. On integrity appraisal error, assuming the file * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. */ -int ima_post_read_file(struct file *file, void *buf, loff_t size, - enum kernel_read_file_id read_id) +static int ima_post_read_file(struct file *file, char *buf, loff_t size, + enum kernel_read_file_id read_id) { enum ima_hooks func; u32 secid; @@ -835,7 +835,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, * * For permission return 0, otherwise return -EACCES. */ -int ima_load_data(enum kernel_load_data_id id, bool contents) +static int ima_load_data(enum kernel_load_data_id id, bool contents) { bool ima_enforce, sig_enforce; @@ -889,9 +889,9 @@ int ima_load_data(enum kernel_load_data_id id, bool contents) * On success return 0. On integrity appraisal error, assuming the file * is in policy and IMA-appraisal is in enforcing mode, return -EACCES. */ -int ima_post_load_data(char *buf, loff_t size, - enum kernel_load_data_id load_id, - char *description) +static int ima_post_load_data(char *buf, loff_t size, + enum kernel_load_data_id load_id, + char *description) { if (load_id == LOADING_FIRMWARE) { if ((ima_appraise & IMA_APPRAISE_FIRMWARE) && @@ -934,7 +934,7 @@ int process_buffer_measurement(struct mnt_idmap *idmap, int ret = 0; const char *audit_cause = "ENOMEM"; struct ima_template_entry *entry = NULL; - struct integrity_iint_cache iint = {}; + struct ima_iint_cache iint = {}; struct ima_event_data event_data = {.iint = &iint, .filename = eventname, .buf = buf, @@ -1089,6 +1089,39 @@ int ima_measure_critical_data(const char *event_label, } EXPORT_SYMBOL_GPL(ima_measure_critical_data); +#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS + +/** + * ima_kernel_module_request - Prevent crypto-pkcs1pad(rsa,*) requests + * @kmod_name: kernel module name + * + * Avoid a verification loop where verifying the signature of the modprobe + * binary requires executing modprobe itself. Since the modprobe iint->mutex + * is already held when the signature verification is performed, a deadlock + * occurs as soon as modprobe is executed within the critical region, since + * the same lock cannot be taken again. + * + * This happens when public_key_verify_signature(), in case of RSA algorithm, + * use alg_name to store internal information in order to construct an + * algorithm on the fly, but crypto_larval_lookup() will try to use alg_name + * in order to load a kernel module with same name. + * + * Since we don't have any real "crypto-pkcs1pad(rsa,*)" kernel modules, + * we are safe to fail such module request from crypto_larval_lookup(), and + * avoid the verification loop. + * + * Return: Zero if it is safe to load the kernel module, -EINVAL otherwise. + */ +static int ima_kernel_module_request(char *kmod_name) +{ + if (strncmp(kmod_name, "crypto-pkcs1pad(rsa,", 20) == 0) + return -EINVAL; + + return 0; +} + +#endif /* CONFIG_INTEGRITY_ASYMMETRIC_KEYS */ + static int __init init_ima(void) { int error; @@ -1120,4 +1153,49 @@ static int __init init_ima(void) return error; } +static struct security_hook_list ima_hooks[] __ro_after_init = { + LSM_HOOK_INIT(bprm_check_security, ima_bprm_check), + LSM_HOOK_INIT(file_post_open, ima_file_check), + LSM_HOOK_INIT(inode_post_create_tmpfile, ima_post_create_tmpfile), + LSM_HOOK_INIT(file_release, ima_file_free), + LSM_HOOK_INIT(mmap_file, ima_file_mmap), + LSM_HOOK_INIT(file_mprotect, ima_file_mprotect), + LSM_HOOK_INIT(kernel_load_data, ima_load_data), + LSM_HOOK_INIT(kernel_post_load_data, ima_post_load_data), + LSM_HOOK_INIT(kernel_read_file, ima_read_file), + LSM_HOOK_INIT(kernel_post_read_file, ima_post_read_file), + LSM_HOOK_INIT(path_post_mknod, ima_post_path_mknod), +#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS + LSM_HOOK_INIT(key_post_create_or_update, ima_post_key_create_or_update), +#endif +#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS + LSM_HOOK_INIT(kernel_module_request, ima_kernel_module_request), +#endif + LSM_HOOK_INIT(inode_free_security, ima_inode_free), +}; + +static const struct lsm_id ima_lsmid = { + .name = "ima", + .id = LSM_ID_IMA, +}; + +static int __init init_ima_lsm(void) +{ + ima_iintcache_init(); + security_add_hooks(ima_hooks, ARRAY_SIZE(ima_hooks), &ima_lsmid); + init_ima_appraise_lsm(&ima_lsmid); + return 0; +} + +struct lsm_blob_sizes ima_blob_sizes __ro_after_init = { + .lbs_inode = sizeof(struct ima_iint_cache *), +}; + +DEFINE_LSM(ima) = { + .name = "ima", + .init = init_ima_lsm, + .order = LSM_ORDER_LAST, + .blobs = &ima_blob_sizes, +}; + late_initcall(init_ima); /* Start IMA after the TPM is available */ diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index f690626177..09da8e6392 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -49,7 +49,7 @@ #define DONT_HASH 0x0200 #define INVALID_PCR(a) (((a) < 0) || \ - (a) >= (sizeof_field(struct integrity_iint_cache, measured_pcrs) * 8)) + (a) >= (sizeof_field(struct ima_iint_cache, measured_pcrs) * 8)) int ima_policy_flag; static int temp_ima_appraise; @@ -401,7 +401,8 @@ static void ima_free_rule(struct ima_rule_entry *entry) kfree(entry); } -static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) +static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry, + gfp_t gfp) { struct ima_rule_entry *nentry; int i; @@ -410,7 +411,7 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) * Immutable elements are copied over as pointers and data; only * lsm rules can change */ - nentry = kmemdup(entry, sizeof(*nentry), GFP_KERNEL); + nentry = kmemdup(entry, sizeof(*nentry), gfp); if (!nentry) return NULL; @@ -425,7 +426,8 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) ima_filter_rule_init(nentry->lsm[i].type, Audit_equal, nentry->lsm[i].args_p, - &nentry->lsm[i].rule); + &nentry->lsm[i].rule, + gfp); if (!nentry->lsm[i].rule) pr_warn("rule for LSM \'%s\' is undefined\n", nentry->lsm[i].args_p); @@ -438,7 +440,7 @@ static int ima_lsm_update_rule(struct ima_rule_entry *entry) int i; struct ima_rule_entry *nentry; - nentry = ima_lsm_copy_rule(entry); + nentry = ima_lsm_copy_rule(entry, GFP_KERNEL); if (!nentry) return -ENOMEM; @@ -664,7 +666,7 @@ retry: } if (rc == -ESTALE && !rule_reinitialized) { - lsm_rule = ima_lsm_copy_rule(rule); + lsm_rule = ima_lsm_copy_rule(rule, GFP_ATOMIC); if (lsm_rule) { rule_reinitialized = true; goto retry; @@ -1140,7 +1142,8 @@ static int ima_lsm_rule_init(struct ima_rule_entry *entry, entry->lsm[lsm_rule].type = audit_type; result = ima_filter_rule_init(entry->lsm[lsm_rule].type, Audit_equal, entry->lsm[lsm_rule].args_p, - &entry->lsm[lsm_rule].rule); + &entry->lsm[lsm_rule].rule, + GFP_KERNEL); if (!entry->lsm[lsm_rule].rule) { pr_warn("rule for LSM \'%s\' is undefined\n", entry->lsm[lsm_rule].args_p); diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c index 6cd0add524..3b2cb8f100 100644 --- a/security/integrity/ima/ima_template_lib.c +++ b/security/integrity/ima/ima_template_lib.c @@ -483,7 +483,10 @@ static int ima_eventname_init_common(struct ima_event_data *event_data, bool size_limit) { const char *cur_filename = NULL; + struct name_snapshot filename; u32 cur_filename_len = 0; + bool snapshot = false; + int ret; BUG_ON(event_data->filename == NULL && event_data->file == NULL); @@ -496,7 +499,10 @@ static int ima_eventname_init_common(struct ima_event_data *event_data, } if (event_data->file) { - cur_filename = event_data->file->f_path.dentry->d_name.name; + take_dentry_name_snapshot(&filename, + event_data->file->f_path.dentry); + snapshot = true; + cur_filename = filename.name.name; cur_filename_len = strlen(cur_filename); } else /* @@ -505,8 +511,13 @@ static int ima_eventname_init_common(struct ima_event_data *event_data, */ cur_filename_len = IMA_EVENT_NAME_LEN_MAX; out: - return ima_write_template_field_data(cur_filename, cur_filename_len, - DATA_FMT_STRING, field_data); + ret = ima_write_template_field_data(cur_filename, cur_filename_len, + DATA_FMT_STRING, field_data); + + if (snapshot) + release_dentry_name_snapshot(&filename); + + return ret; } /* |