From bad5247a2c4f7eab6fb922af3362740a562dc665 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:49 +0100 Subject: ima: Align ima_inode_post_setattr() definition with LSM infrastructure Change ima_inode_post_setattr() definition, so that it can be registered as implementation of the inode_post_setattr hook (to be introduced). Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 86b57757c7b1..910a2f11a906 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -186,7 +186,7 @@ static inline void ima_post_key_create_or_update(struct key *keyring, #ifdef CONFIG_IMA_APPRAISE extern bool is_ima_appraise_enabled(void); extern void ima_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry); + struct dentry *dentry, int ia_valid); extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, const void *xattr_value, size_t xattr_value_len); extern int ima_inode_set_acl(struct mnt_idmap *idmap, @@ -206,7 +206,7 @@ static inline bool is_ima_appraise_enabled(void) } static inline void ima_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry) + struct dentry *dentry, int ia_valid) { return; } -- cgit v1.2.3 From 0298c5a9b168f0d74ea3bf881301c4bd9252d367 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:50 +0100 Subject: ima: Align ima_file_mprotect() definition with LSM infrastructure Change ima_file_mprotect() definition, so that it can be registered as implementation of the file_mprotect hook. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 910a2f11a906..b66353f679e8 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -23,7 +23,8 @@ extern void ima_post_create_tmpfile(struct mnt_idmap *idmap, extern void ima_file_free(struct file *file); extern int ima_file_mmap(struct file *file, unsigned long reqprot, unsigned long prot, unsigned long flags); -extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot); +extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, + unsigned long prot); extern int ima_load_data(enum kernel_load_data_id id, bool contents); extern int ima_post_load_data(char *buf, loff_t size, enum kernel_load_data_id id, char *description); @@ -84,7 +85,7 @@ static inline int ima_file_mmap(struct file *file, unsigned long reqprot, } static inline int ima_file_mprotect(struct vm_area_struct *vma, - unsigned long prot) + unsigned long reqprot, unsigned long prot) { return 0; } -- cgit v1.2.3 From fbd0506e5c5874fd52403fd38e3e77d895689870 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:51 +0100 Subject: ima: Align ima_inode_setxattr() definition with LSM infrastructure Change ima_inode_setxattr() definition, so that it can be registered as implementation of the inode_setxattr hook. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index b66353f679e8..077324309c11 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -188,8 +188,9 @@ static inline void ima_post_key_create_or_update(struct key *keyring, extern bool is_ima_appraise_enabled(void); extern void ima_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, int ia_valid); -extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name, - const void *xattr_value, size_t xattr_value_len); +extern 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); extern int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl); @@ -212,10 +213,12 @@ static inline void ima_inode_post_setattr(struct mnt_idmap *idmap, return; } -static inline int ima_inode_setxattr(struct dentry *dentry, +static inline int ima_inode_setxattr(struct mnt_idmap *idmap, + struct dentry *dentry, const char *xattr_name, const void *xattr_value, - size_t xattr_value_len) + size_t xattr_value_len, + int flags) { return 0; } -- cgit v1.2.3 From 526864dd2f60c16bcdc84e9e7bc6d69d08cfee21 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:52 +0100 Subject: ima: Align ima_inode_removexattr() definition with LSM infrastructure Change ima_inode_removexattr() definition, so that it can be registered as implementation of the inode_removexattr hook. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 077324309c11..678a03fddd7e 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -200,7 +200,9 @@ static inline int ima_inode_remove_acl(struct mnt_idmap *idmap, { return ima_inode_set_acl(idmap, dentry, acl_name, NULL); } -extern int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name); + +extern int ima_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, + const char *xattr_name); #else static inline bool is_ima_appraise_enabled(void) { @@ -231,7 +233,8 @@ static inline int ima_inode_set_acl(struct mnt_idmap *idmap, return 0; } -static inline int ima_inode_removexattr(struct dentry *dentry, +static inline int ima_inode_removexattr(struct mnt_idmap *idmap, + struct dentry *dentry, const char *xattr_name) { return 0; -- cgit v1.2.3 From fec5f85e468d6f47851d531ec81f9da821768e00 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:53 +0100 Subject: ima: Align ima_post_read_file() definition with LSM infrastructure Change ima_post_read_file() definition, by making "void *buf" a "char *buf", so that it can be registered as implementation of the post_read_file hook. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 678a03fddd7e..31ef6c3c3207 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -30,7 +30,7 @@ extern int ima_post_load_data(char *buf, loff_t size, enum kernel_load_data_id id, char *description); extern int ima_read_file(struct file *file, enum kernel_read_file_id id, bool contents); -extern int ima_post_read_file(struct file *file, void *buf, loff_t size, +extern int ima_post_read_file(struct file *file, char *buf, loff_t size, enum kernel_read_file_id id); extern void ima_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry); @@ -108,7 +108,7 @@ static inline int ima_read_file(struct file *file, enum kernel_read_file_id id, return 0; } -static inline int ima_post_read_file(struct file *file, void *buf, loff_t size, +static inline int ima_post_read_file(struct file *file, char *buf, loff_t size, enum kernel_read_file_id id) { return 0; -- cgit v1.2.3 From 06cca5110774f7b59a1685431ac697865588f4ca Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:07 +0100 Subject: integrity: Move integrity_kernel_module_request() to IMA In preparation for removing the 'integrity' LSM, move integrity_kernel_module_request() to IMA, and rename it to ima_kernel_module_request(). Rewrite the function documentation, to explain better what the problem is. Compile it conditionally if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled, and call it from security.c (removed afterwards with the move of IMA to the LSM infrastructure). Adding this hook cannot be avoided, since IMA has no control on the flags passed to crypto_alloc_sig() in public_key_verify_signature(), and thus cannot pass CRYPTO_NOLOAD, which solved the problem for EVM hashing with commit e2861fa71641 ("evm: Don't deadlock if a crypto algorithm is unavailable"). EVM alone does not need to implement this hook, first because there is no mutex to deadlock, and second because even if it had it, there should be a recursive call. However, since verification from EVM can be initiated only by setting inode metadata, deadlock would occur if modprobe would do the same while loading a kernel module (which is unlikely). Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 31ef6c3c3207..0f9af283cbc8 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -256,4 +256,14 @@ static inline bool ima_appraise_signature(enum kernel_read_file_id func) return false; } #endif /* CONFIG_IMA_APPRAISE && CONFIG_INTEGRITY_TRUSTED_KEYRING */ + +#if defined(CONFIG_IMA) && defined(CONFIG_INTEGRITY_ASYMMETRIC_KEYS) +extern int ima_kernel_module_request(char *kmod_name); +#else +static inline int ima_kernel_module_request(char *kmod_name) +{ + return 0; +} + +#endif #endif /* _LINUX_IMA_H */ -- cgit v1.2.3 From cd3cec0a02c7338ce2901c574f3935b8f6984aab Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:08 +0100 Subject: ima: Move to LSM infrastructure Move hardcoded IMA function calls (not appraisal-specific functions) from various places in the kernel to the LSM infrastructure, by introducing a new LSM named 'ima' (at the end of the LSM list and always enabled like 'integrity'). Having IMA before EVM in the Makefile is sufficient to preserve the relative order of the new 'ima' LSM in respect to the upcoming 'evm' LSM, and thus the order of IMA and EVM function calls as when they were hardcoded. Make moved functions as static (except ima_post_key_create_or_update(), which is not in ima_main.c), and register them as implementation of the respective hooks in the new function init_ima_lsm(). Select CONFIG_SECURITY_PATH, to ensure that the path-based LSM hook path_post_mknod is always available and ima_post_path_mknod() is always executed to mark files as new, as before the move. A slight difference is that IMA and EVM functions registered for the inode_post_setattr, inode_post_removexattr, path_post_mknod, inode_post_create_tmpfile, inode_post_set_acl and inode_post_remove_acl won't be executed for private inodes. Since those inodes are supposed to be fs-internal, they should not be of interest to IMA or EVM. The S_PRIVATE flag is used for anonymous inodes, hugetlbfs, reiserfs xattrs, XFS scrub and kernel-internal tmpfs files. Conditionally register ima_post_key_create_or_update() if CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Also, conditionally register ima_kernel_module_request() if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled. Finally, add the LSM_ID_IMA case in lsm_list_modules_test.c. Signed-off-by: Roberto Sassu Acked-by: Chuck Lever Acked-by: Casey Schaufler Acked-by: Christian Brauner Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 104 ---------------------------------------------------- 1 file changed, 104 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 0f9af283cbc8..23ae24b60ecf 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -16,24 +16,6 @@ struct linux_binprm; #ifdef CONFIG_IMA extern enum hash_algo ima_get_current_hash_algo(void); -extern int ima_bprm_check(struct linux_binprm *bprm); -extern int ima_file_check(struct file *file, int mask); -extern void ima_post_create_tmpfile(struct mnt_idmap *idmap, - struct inode *inode); -extern void ima_file_free(struct file *file); -extern int ima_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags); -extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot, - unsigned long prot); -extern int ima_load_data(enum kernel_load_data_id id, bool contents); -extern int ima_post_load_data(char *buf, loff_t size, - enum kernel_load_data_id id, char *description); -extern int ima_read_file(struct file *file, enum kernel_read_file_id id, - bool contents); -extern int ima_post_read_file(struct file *file, char *buf, loff_t size, - enum kernel_read_file_id id); -extern void ima_post_path_mknod(struct mnt_idmap *idmap, - struct dentry *dentry); extern int ima_file_hash(struct file *file, char *buf, size_t buf_size); extern int ima_inode_hash(struct inode *inode, char *buf, size_t buf_size); extern void ima_kexec_cmdline(int kernel_fd, const void *buf, int size); @@ -58,68 +40,6 @@ static inline enum hash_algo ima_get_current_hash_algo(void) return HASH_ALGO__LAST; } -static inline int ima_bprm_check(struct linux_binprm *bprm) -{ - return 0; -} - -static inline int ima_file_check(struct file *file, int mask) -{ - return 0; -} - -static inline void ima_post_create_tmpfile(struct mnt_idmap *idmap, - struct inode *inode) -{ -} - -static inline void ima_file_free(struct file *file) -{ - return; -} - -static inline int ima_file_mmap(struct file *file, unsigned long reqprot, - unsigned long prot, unsigned long flags) -{ - return 0; -} - -static inline int ima_file_mprotect(struct vm_area_struct *vma, - unsigned long reqprot, unsigned long prot) -{ - return 0; -} - -static inline int ima_load_data(enum kernel_load_data_id id, bool contents) -{ - return 0; -} - -static inline int ima_post_load_data(char *buf, loff_t size, - enum kernel_load_data_id id, - char *description) -{ - return 0; -} - -static inline int ima_read_file(struct file *file, enum kernel_read_file_id id, - bool contents) -{ - return 0; -} - -static inline int ima_post_read_file(struct file *file, char *buf, loff_t size, - enum kernel_read_file_id id) -{ - return 0; -} - -static inline void ima_post_path_mknod(struct mnt_idmap *idmap, - struct dentry *dentry) -{ - return; -} - static inline int ima_file_hash(struct file *file, char *buf, size_t buf_size) { return -EOPNOTSUPP; @@ -170,20 +90,6 @@ static inline void ima_add_kexec_buffer(struct kimage *image) {} #endif -#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS -extern void ima_post_key_create_or_update(struct key *keyring, - struct key *key, - const void *payload, size_t plen, - unsigned long flags, bool create); -#else -static inline 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 /* CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS */ - #ifdef CONFIG_IMA_APPRAISE extern bool is_ima_appraise_enabled(void); extern void ima_inode_post_setattr(struct mnt_idmap *idmap, @@ -256,14 +162,4 @@ static inline bool ima_appraise_signature(enum kernel_read_file_id func) return false; } #endif /* CONFIG_IMA_APPRAISE && CONFIG_INTEGRITY_TRUSTED_KEYRING */ - -#if defined(CONFIG_IMA) && defined(CONFIG_INTEGRITY_ASYMMETRIC_KEYS) -extern int ima_kernel_module_request(char *kmod_name); -#else -static inline int ima_kernel_module_request(char *kmod_name) -{ - return 0; -} - -#endif #endif /* _LINUX_IMA_H */ -- cgit v1.2.3 From 84594c9ecdca7ca595bc50e315093cb76921fd8e Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:09 +0100 Subject: ima: Move IMA-Appraisal to LSM infrastructure A few additional IMA hooks are needed to reset the cached appraisal status, causing the file's integrity to be re-evaluated on next access. Register these IMA-appraisal only functions separately from the rest of IMA functions, as appraisal is a separate feature not necessarily enabled in the kernel configuration. Reuse the same approach as for other IMA functions, move hardcoded calls from various places in the kernel to the LSM infrastructure. Declare the functions as static and register them as hook implementations in init_ima_appraise_lsm(), called by init_ima_lsm(). Also move the inline function ima_inode_remove_acl() from the public ima.h header to ima_appraise.c. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler Acked-by: Christian Brauner Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/ima.h | 55 ----------------------------------------------------- 1 file changed, 55 deletions(-) (limited to 'include/linux/ima.h') diff --git a/include/linux/ima.h b/include/linux/ima.h index 23ae24b60ecf..0bae61a15b60 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -92,66 +92,11 @@ static inline void ima_add_kexec_buffer(struct kimage *image) #ifdef CONFIG_IMA_APPRAISE extern bool is_ima_appraise_enabled(void); -extern void ima_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry, int ia_valid); -extern 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); -extern int ima_inode_set_acl(struct mnt_idmap *idmap, - struct dentry *dentry, const char *acl_name, - struct posix_acl *kacl); -static inline 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); -} - -extern int ima_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, - const char *xattr_name); #else static inline bool is_ima_appraise_enabled(void) { return 0; } - -static inline void ima_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry, int ia_valid) -{ - return; -} - -static inline 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) -{ - return 0; -} - -static inline int ima_inode_set_acl(struct mnt_idmap *idmap, - struct dentry *dentry, const char *acl_name, - struct posix_acl *kacl) -{ - - return 0; -} - -static inline int ima_inode_removexattr(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *xattr_name) -{ - return 0; -} - -static inline int ima_inode_remove_acl(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *acl_name) -{ - return 0; -} #endif /* CONFIG_IMA_APPRAISE */ #if defined(CONFIG_IMA_APPRAISE) && defined(CONFIG_INTEGRITY_TRUSTED_KEYRING) -- cgit v1.2.3