Message ID | 20240115181809.885385-25-roberto.sassu@huaweicloud.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | security: Move IMA and EVM to the LSM infrastructure | expand |
On 1/15/2024 10:18 AM, Roberto Sassu wrote: > From: Roberto Sassu <roberto.sassu@huawei.com> > > Make the 'ima' LSM independent from the 'integrity' LSM by introducing IMA > own integrity metadata (ima_iint_cache structure, with IMA-specific fields > from the integrity_iint_cache structure), and by managing it directly from > the 'ima' LSM. > > Create ima_iint.c and introduce the same integrity metadata management > functions found in iint.c (renamed with ima_). However, instead of putting > metadata in an rbtree, reserve space from IMA in the inode security blob > for a pointer, and introduce the ima_inode_set_iint()/ima_inode_get_iint() > primitives to store/retrieve that pointer. This improves search time from > logarithm to constant. > > Consequently, don't include the inode pointer as field in the > ima_iint_cache structure, since the association with the inode is clear. > Since the inode field is missing in ima_iint_cache, pass the extra inode > parameter to ima_get_verity_digest(). > > Prefer storing the pointer instead of the entire ima_iint_cache structure, > to avoid too much memory pressure. Use the same mechanism as before, a > cache named ima_iint_cache (renamed from iint_cache), to quickly allocate > a new ima_iint_cache structure when requested by the IMA policy. > > Create the new ima_iint_cache in ima_iintcache_init(), > called by init_ima_lsm(), during the initialization of the 'ima' LSM. And, > register ima_inode_free_security() to free the ima_iint_cache structure, if > exists. > > Replace integrity_iint_cache with ima_iint_cache in various places of the > IMA code. Also, replace integrity_inode_get() and integrity_iint_find(), > respectively with ima_inode_get() and ima_iint_find(). > > Finally, move the remaining IMA-specific flags > to security/integrity/ima/ima.h, since they are now unnecessary in the > common integrity layer. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>4 > --- > security/integrity/ima/Makefile | 2 +- > security/integrity/ima/ima.h | 137 +++++++++++++++++++++---- > security/integrity/ima/ima_api.c | 23 +++-- > security/integrity/ima/ima_appraise.c | 27 +++-- > security/integrity/ima/ima_iint.c | 142 ++++++++++++++++++++++++++ > security/integrity/ima/ima_init.c | 2 +- > security/integrity/ima/ima_main.c | 36 ++++--- > security/integrity/ima/ima_policy.c | 2 +- > security/integrity/integrity.h | 53 ---------- > 9 files changed, 308 insertions(+), 116 deletions(-) > create mode 100644 security/integrity/ima/ima_iint.c > > diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile > index 2499f2485c04..b376d38b4ee6 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 a27fc10f84f7..11d7c0332207 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 > @@ -152,8 +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); > @@ -267,10 +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, > @@ -280,7 +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, > @@ -318,17 +419,16 @@ 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); > @@ -337,14 +437,14 @@ int ima_read_xattr(struct dentry *dentry, > 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, > @@ -361,14 +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; > } > diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c > index 597ea0c4d72f..b37d043d5748 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; > > @@ -237,9 +238,9 @@ 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); > @@ -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; > } > @@ -338,8 +339,8 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, > * > * 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 +383,7 @@ 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; > diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c > index 1dd6ee72a20a..3497741caea9 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) > @@ -603,7 +600,7 @@ int ima_appraise_measurement(enum ima_hooks func, > /* > * 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; > @@ -640,7 +637,7 @@ 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) > @@ -648,7 +645,7 @@ static 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) > @@ -674,12 +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; > diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c > new file mode 100644 > index 000000000000..e7c9c216c1c6 > --- /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 63979aefc95f..393f5c7912d5 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 77d0d4e4b582..45f1a102c599 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; > @@ -192,12 +192,12 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint, > 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; > } > @@ -564,11 +564,11 @@ static int ima_file_check(struct file *file, int mask) > 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); > } > @@ -578,7 +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, > @@ -688,7 +687,7 @@ 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)) > @@ -700,7 +699,7 @@ static 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; > > @@ -719,7 +718,7 @@ static void ima_post_create_tmpfile(struct mnt_idmap *idmap, > */ > 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; > > @@ -732,7 +731,7 @@ static void ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry) > return; > > /* Nothing to do if we can't allocate memory */ > - iint = integrity_inode_get(inode); > + iint = ima_inode_get(inode); > if (!iint) > return; > > @@ -935,7 +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, > @@ -1168,6 +1167,7 @@ static struct security_hook_list ima_hooks[] __ro_after_init = { > #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 = { > @@ -1177,15 +1177,21 @@ static const struct lsm_id ima_lsmid = { > > 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 f69062617754..c0556907c2e6 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; > diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h > index 7a97c269a072..671fc50255f9 100644 > --- a/security/integrity/integrity.h > +++ b/security/integrity/integrity.h > @@ -20,59 +20,6 @@ > #include <linux/audit.h> > #include <linux/lsm_hooks.h> > > -/* 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 > - > -/* 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) > - > -/* 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) > - > -/* 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 > - > enum evm_ima_xattr_type { > IMA_XATTR_DIGEST = 0x01, > EVM_XATTR_HMAC,
On 1/15/24 13:18, Roberto Sassu wrote: > From: Roberto Sassu <roberto.sassu@huawei.com> > > Make the 'ima' LSM independent from the 'integrity' LSM by introducing IMA > own integrity metadata (ima_iint_cache structure, with IMA-specific fields > from the integrity_iint_cache structure), and by managing it directly from > the 'ima' LSM. > > Create ima_iint.c and introduce the same integrity metadata management > functions found in iint.c (renamed with ima_). However, instead of putting > metadata in an rbtree, reserve space from IMA in the inode security blob > for a pointer, and introduce the ima_inode_set_iint()/ima_inode_get_iint() > primitives to store/retrieve that pointer. This improves search time from > logarithm to constant. logarithmic > > Consequently, don't include the inode pointer as field in the > ima_iint_cache structure, since the association with the inode is clear. > Since the inode field is missing in ima_iint_cache, pass the extra inode > parameter to ima_get_verity_digest(). > > Prefer storing the pointer instead of the entire ima_iint_cache structure, > to avoid too much memory pressure. Use the same mechanism as before, a > cache named ima_iint_cache (renamed from iint_cache), to quickly allocate > a new ima_iint_cache structure when requested by the IMA policy. > > Create the new ima_iint_cache in ima_iintcache_init(), > called by init_ima_lsm(), during the initialization of the 'ima' LSM. And, > register ima_inode_free_security() to free the ima_iint_cache structure, if > exists. > > Replace integrity_iint_cache with ima_iint_cache in various places of the > IMA code. Also, replace integrity_inode_get() and integrity_iint_find(), > respectively with ima_inode_get() and ima_iint_find(). > > Finally, move the remaining IMA-specific flags > to security/integrity/ima/ima.h, since they are now unnecessary in the > common integrity layer. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile index 2499f2485c04..b376d38b4ee6 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 a27fc10f84f7..11d7c0332207 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 @@ -152,8 +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); @@ -267,10 +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, @@ -280,7 +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, @@ -318,17 +419,16 @@ 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); @@ -337,14 +437,14 @@ int ima_read_xattr(struct dentry *dentry, 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, @@ -361,14 +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; } diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index 597ea0c4d72f..b37d043d5748 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; @@ -237,9 +238,9 @@ 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); @@ -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; } @@ -338,8 +339,8 @@ int ima_collect_measurement(struct integrity_iint_cache *iint, * * 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 +383,7 @@ 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; diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 1dd6ee72a20a..3497741caea9 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) @@ -603,7 +600,7 @@ int ima_appraise_measurement(enum ima_hooks func, /* * 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; @@ -640,7 +637,7 @@ 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) @@ -648,7 +645,7 @@ static 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) @@ -674,12 +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; diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c new file mode 100644 index 000000000000..e7c9c216c1c6 --- /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 63979aefc95f..393f5c7912d5 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 77d0d4e4b582..45f1a102c599 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; @@ -192,12 +192,12 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint, 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; } @@ -564,11 +564,11 @@ static int ima_file_check(struct file *file, int mask) 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); } @@ -578,7 +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, @@ -688,7 +687,7 @@ 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)) @@ -700,7 +699,7 @@ static 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; @@ -719,7 +718,7 @@ static void ima_post_create_tmpfile(struct mnt_idmap *idmap, */ 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; @@ -732,7 +731,7 @@ static void ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry) return; /* Nothing to do if we can't allocate memory */ - iint = integrity_inode_get(inode); + iint = ima_inode_get(inode); if (!iint) return; @@ -935,7 +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, @@ -1168,6 +1167,7 @@ static struct security_hook_list ima_hooks[] __ro_after_init = { #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 = { @@ -1177,15 +1177,21 @@ static const struct lsm_id ima_lsmid = { 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 f69062617754..c0556907c2e6 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; diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 7a97c269a072..671fc50255f9 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -20,59 +20,6 @@ #include <linux/audit.h> #include <linux/lsm_hooks.h> -/* 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 - -/* 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) - -/* 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) - -/* 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 - enum evm_ima_xattr_type { IMA_XATTR_DIGEST = 0x01, EVM_XATTR_HMAC,