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') 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') 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') 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') 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') 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 784111d0093e007950cc20033daf3d74ac388821 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:54 +0100 Subject: evm: Align evm_inode_post_setattr() definition with LSM infrastructure Change evm_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/evm.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/evm.h b/include/linux/evm.h index 36ec884320d9..5cc386312b5a 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -23,7 +23,8 @@ extern enum integrity_status evm_verifyxattr(struct dentry *dentry, struct integrity_iint_cache *iint); extern int evm_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr); -extern void evm_inode_post_setattr(struct dentry *dentry, int ia_valid); +extern void evm_inode_post_setattr(struct mnt_idmap *idmap, + struct dentry *dentry, int ia_valid); extern int evm_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, size_t size); @@ -98,7 +99,8 @@ static inline int evm_inode_setattr(struct mnt_idmap *idmap, return 0; } -static inline void evm_inode_post_setattr(struct dentry *dentry, int ia_valid) +static inline void evm_inode_post_setattr(struct mnt_idmap *idmap, + struct dentry *dentry, int ia_valid) { return; } -- cgit v1.2.3 From 2b6a4054f8c2758cf5c1d78f6ba7006a940b31ce Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:55 +0100 Subject: evm: Align evm_inode_setxattr() definition with LSM infrastructure Change evm_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/evm.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/evm.h b/include/linux/evm.h index 5cc386312b5a..7de24c1ada90 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -27,7 +27,7 @@ extern void evm_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, int ia_valid); extern int evm_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, - const void *value, size_t size); + const void *value, size_t size, int flags); extern void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name, const void *xattr_value, @@ -107,7 +107,7 @@ static inline void evm_inode_post_setattr(struct mnt_idmap *idmap, static inline int evm_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, - const void *value, size_t size) + const void *value, size_t size, int flags) { return 0; } -- cgit v1.2.3 From 779cb1947e270504c66a96fc0b7e6e31c748b1e1 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:56 +0100 Subject: evm: Align evm_inode_post_setxattr() definition with LSM infrastructure Change evm_inode_post_setxattr() definition, so that it can be registered as implementation of the inode_post_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/evm.h | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/linux/evm.h b/include/linux/evm.h index 7de24c1ada90..3faabdd47852 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -31,7 +31,8 @@ extern int evm_inode_setxattr(struct mnt_idmap *idmap, extern void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name, const void *xattr_value, - size_t xattr_value_len); + size_t xattr_value_len, + int flags); extern int evm_inode_copy_up_xattr(const char *name); extern int evm_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *xattr_name); @@ -56,7 +57,7 @@ static inline void evm_inode_post_set_acl(struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) { - return evm_inode_post_setxattr(dentry, acl_name, NULL, 0); + return evm_inode_post_setxattr(dentry, acl_name, NULL, 0, 0); } int evm_inode_init_security(struct inode *inode, struct inode *dir, @@ -115,7 +116,8 @@ static inline int evm_inode_setxattr(struct mnt_idmap *idmap, static inline void evm_inode_post_setxattr(struct dentry *dentry, const char *xattr_name, const void *xattr_value, - size_t xattr_value_len) + size_t xattr_value_len, + int flags) { return; } -- cgit v1.2.3 From 314a8dc728d038378795236f6b5199265f921f45 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:57 +0100 Subject: security: Align inode_setattr hook definition with EVM Add the idmap parameter to the definition, so that evm_inode_setattr() can be registered as this hook implementation. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 76458b6d53da..b00b16d58413 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -135,7 +135,8 @@ LSM_HOOK(int, 0, inode_readlink, struct dentry *dentry) LSM_HOOK(int, 0, inode_follow_link, struct dentry *dentry, struct inode *inode, bool rcu) LSM_HOOK(int, 0, inode_permission, struct inode *inode, int mask) -LSM_HOOK(int, 0, inode_setattr, struct dentry *dentry, struct iattr *attr) +LSM_HOOK(int, 0, inode_setattr, struct mnt_idmap *idmap, struct dentry *dentry, + struct iattr *attr) LSM_HOOK(int, 0, inode_getattr, const struct path *path) LSM_HOOK(int, 0, inode_setxattr, struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, -- cgit v1.2.3 From 77fa6f314f0376176ef6bf3d84403e0d8b54ce28 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:58 +0100 Subject: security: Introduce inode_post_setattr hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_setattr hook. At inode_setattr hook, EVM verifies the file's existing HMAC value. At inode_post_setattr, EVM re-calculates the file's HMAC based on the modified file attributes and other file metadata. Other LSMs could similarly take some action after successful file attribute change. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Acked-by: Casey Schaufler Acked-by: Christian Brauner Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 2 ++ include/linux/security.h | 7 +++++++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index b00b16d58413..a0e9e48015a4 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -137,6 +137,8 @@ LSM_HOOK(int, 0, inode_follow_link, struct dentry *dentry, struct inode *inode, LSM_HOOK(int, 0, inode_permission, struct inode *inode, int mask) LSM_HOOK(int, 0, inode_setattr, struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr) +LSM_HOOK(void, LSM_RET_VOID, inode_post_setattr, struct mnt_idmap *idmap, + struct dentry *dentry, int ia_valid) LSM_HOOK(int, 0, inode_getattr, const struct path *path) LSM_HOOK(int, 0, inode_setxattr, struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, diff --git a/include/linux/security.h b/include/linux/security.h index d0eb20f90b26..56c841aa3994 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -361,6 +361,8 @@ int security_inode_follow_link(struct dentry *dentry, struct inode *inode, int security_inode_permission(struct inode *inode, int mask); int security_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct iattr *attr); +void security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, + int ia_valid); int security_inode_getattr(const struct path *path); int security_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, @@ -879,6 +881,11 @@ static inline int security_inode_setattr(struct mnt_idmap *idmap, return 0; } +static inline void +security_inode_post_setattr(struct mnt_idmap *idmap, struct dentry *dentry, + int ia_valid) +{ } + static inline int security_inode_getattr(const struct path *path) { return 0; -- cgit v1.2.3 From dae52cbf5887ac51c3574648124cfe475a9b3246 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:30:59 +0100 Subject: security: Introduce inode_post_removexattr hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_removexattr hook. At inode_removexattr hook, EVM verifies the file's existing HMAC value. At inode_post_removexattr, EVM re-calculates the file's HMAC with the passed xattr removed and other file metadata. Other LSMs could similarly take some action after successful xattr removal. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Reviewed-by: Casey Schaufler Acked-by: Christian Brauner Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 2 ++ include/linux/security.h | 5 +++++ 2 files changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index a0e9e48015a4..f849f7d5bb53 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -149,6 +149,8 @@ LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name) LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry) LSM_HOOK(int, 0, inode_removexattr, struct mnt_idmap *idmap, struct dentry *dentry, const char *name) +LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, + const char *name) LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, diff --git a/include/linux/security.h b/include/linux/security.h index 56c841aa3994..84ae03690340 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -380,6 +380,7 @@ int security_inode_getxattr(struct dentry *dentry, const char *name); int security_inode_listxattr(struct dentry *dentry); int security_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name); +void security_inode_post_removexattr(struct dentry *dentry, const char *name); int security_inode_need_killpriv(struct dentry *dentry); int security_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry); int security_inode_getsecurity(struct mnt_idmap *idmap, @@ -942,6 +943,10 @@ static inline int security_inode_removexattr(struct mnt_idmap *idmap, return cap_inode_removexattr(idmap, dentry, name); } +static inline void security_inode_post_removexattr(struct dentry *dentry, + const char *name) +{ } + static inline int security_inode_need_killpriv(struct dentry *dentry) { return cap_inode_need_killpriv(dentry); -- cgit v1.2.3 From 8f46ff5767b0b18329140d80d6bcabd818f42c4c Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:00 +0100 Subject: security: Introduce file_post_open hook In preparation to move IMA and EVM to the LSM infrastructure, introduce the file_post_open hook. Also, export security_file_post_open() for NFS. Based on policy, IMA calculates the digest of the file content and extends the TPM with the digest, verifies the file's integrity based on the digest, and/or includes the file digest in the audit log. LSMs could similarly take action depending on the file content and the access mask requested with open(). The new hook returns a value and can cause the open to be aborted. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Christian Brauner Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 1 + include/linux/security.h | 6 ++++++ 2 files changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index f849f7d5bb53..3c84942d2818 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -191,6 +191,7 @@ LSM_HOOK(int, 0, file_send_sigiotask, struct task_struct *tsk, struct fown_struct *fown, int sig) LSM_HOOK(int, 0, file_receive, struct file *file) LSM_HOOK(int, 0, file_open, struct file *file) +LSM_HOOK(int, 0, file_post_open, struct file *file, int mask) LSM_HOOK(int, 0, file_truncate, struct file *file) LSM_HOOK(int, 0, task_alloc, struct task_struct *task, unsigned long clone_flags) diff --git a/include/linux/security.h b/include/linux/security.h index 84ae03690340..97f2212c13b6 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -411,6 +411,7 @@ int security_file_send_sigiotask(struct task_struct *tsk, struct fown_struct *fown, int sig); int security_file_receive(struct file *file); int security_file_open(struct file *file); +int security_file_post_open(struct file *file, int mask); int security_file_truncate(struct file *file); int security_task_alloc(struct task_struct *task, unsigned long clone_flags); void security_task_free(struct task_struct *task); @@ -1074,6 +1075,11 @@ static inline int security_file_open(struct file *file) return 0; } +static inline int security_file_post_open(struct file *file, int mask) +{ + return 0; +} + static inline int security_file_truncate(struct file *file) { return 0; -- cgit v1.2.3 From f09068b5a114ed28d2df2e82a7d30dde0145dc69 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:01 +0100 Subject: security: Introduce file_release hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the file_release hook. IMA calculates at file close the new digest of the file content and writes it to security.ima, so that appraisal at next file access succeeds. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Acked-by: Christian Brauner Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 1 + include/linux/security.h | 4 ++++ 2 files changed, 5 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 3c84942d2818..7f9e9240606e 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -173,6 +173,7 @@ LSM_HOOK(int, 0, kernfs_init_security, struct kernfs_node *kn_dir, struct kernfs_node *kn) LSM_HOOK(int, 0, file_permission, struct file *file, int mask) LSM_HOOK(int, 0, file_alloc_security, struct file *file) +LSM_HOOK(void, LSM_RET_VOID, file_release, struct file *file) LSM_HOOK(void, LSM_RET_VOID, file_free_security, struct file *file) LSM_HOOK(int, 0, file_ioctl, struct file *file, unsigned int cmd, unsigned long arg) diff --git a/include/linux/security.h b/include/linux/security.h index 97f2212c13b6..2997348afcb7 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -395,6 +395,7 @@ int security_kernfs_init_security(struct kernfs_node *kn_dir, struct kernfs_node *kn); int security_file_permission(struct file *file, int mask); int security_file_alloc(struct file *file); +void security_file_release(struct file *file); void security_file_free(struct file *file); int security_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg); int security_file_ioctl_compat(struct file *file, unsigned int cmd, @@ -1008,6 +1009,9 @@ static inline int security_file_alloc(struct file *file) return 0; } +static inline void security_file_release(struct file *file) +{ } + static inline void security_file_free(struct file *file) { } -- cgit v1.2.3 From 08abce60d63fb55f440c393f4508e99064f2fd91 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:02 +0100 Subject: security: Introduce path_post_mknod hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the path_post_mknod hook. IMA-appraisal requires all existing files in policy to have a file hash/signature stored in security.ima. An exception is made for empty files created by mknod, by tagging them as new files. LSMs could also take some action after files are created. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Christian Brauner Reviewed-by: Stefan Berger Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 2 ++ include/linux/security.h | 5 +++++ 2 files changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 7f9e9240606e..dba5d8204dc5 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -94,6 +94,8 @@ LSM_HOOK(int, 0, path_mkdir, const struct path *dir, struct dentry *dentry, LSM_HOOK(int, 0, path_rmdir, const struct path *dir, struct dentry *dentry) LSM_HOOK(int, 0, path_mknod, const struct path *dir, struct dentry *dentry, umode_t mode, unsigned int dev) +LSM_HOOK(void, LSM_RET_VOID, path_post_mknod, struct mnt_idmap *idmap, + struct dentry *dentry) LSM_HOOK(int, 0, path_truncate, const struct path *path) LSM_HOOK(int, 0, path_symlink, const struct path *dir, struct dentry *dentry, const char *old_name) diff --git a/include/linux/security.h b/include/linux/security.h index 2997348afcb7..977dd9f7f51a 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1893,6 +1893,7 @@ int security_path_mkdir(const struct path *dir, struct dentry *dentry, umode_t m int security_path_rmdir(const struct path *dir, struct dentry *dentry); int security_path_mknod(const struct path *dir, struct dentry *dentry, umode_t mode, unsigned int dev); +void security_path_post_mknod(struct mnt_idmap *idmap, struct dentry *dentry); int security_path_truncate(const struct path *path); int security_path_symlink(const struct path *dir, struct dentry *dentry, const char *old_name); @@ -1927,6 +1928,10 @@ static inline int security_path_mknod(const struct path *dir, struct dentry *den return 0; } +static inline void security_path_post_mknod(struct mnt_idmap *idmap, + struct dentry *dentry) +{ } + static inline int security_path_truncate(const struct path *path) { return 0; -- cgit v1.2.3 From a7811e34d100acf24870eb949c5ae3e49dde18b9 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:03 +0100 Subject: security: Introduce inode_post_create_tmpfile hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_create_tmpfile hook. As temp files can be made persistent, treat new temp files like other new files, so that the file hash is calculated and stored in the security xattr. LSMs could also take some action after temp files have been created. The new hook cannot return an error and cannot cause the operation to be canceled. Signed-off-by: Roberto Sassu Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Christian Brauner Reviewed-by: Stefan Berger Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 2 ++ include/linux/security.h | 6 ++++++ 2 files changed, 8 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index dba5d8204dc5..87f60b47dfca 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -121,6 +121,8 @@ LSM_HOOK(int, 0, inode_init_security_anon, struct inode *inode, const struct qstr *name, const struct inode *context_inode) LSM_HOOK(int, 0, inode_create, struct inode *dir, struct dentry *dentry, umode_t mode) +LSM_HOOK(void, LSM_RET_VOID, inode_post_create_tmpfile, struct mnt_idmap *idmap, + struct inode *inode) LSM_HOOK(int, 0, inode_link, struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) LSM_HOOK(int, 0, inode_unlink, struct inode *dir, struct dentry *dentry) diff --git a/include/linux/security.h b/include/linux/security.h index 977dd9f7f51a..1cb604282617 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -344,6 +344,8 @@ int security_inode_init_security_anon(struct inode *inode, const struct qstr *name, const struct inode *context_inode); int security_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode); +void security_inode_post_create_tmpfile(struct mnt_idmap *idmap, + struct inode *inode); int security_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry); int security_inode_unlink(struct inode *dir, struct dentry *dentry); @@ -811,6 +813,10 @@ static inline int security_inode_create(struct inode *dir, return 0; } +static inline void +security_inode_post_create_tmpfile(struct mnt_idmap *idmap, struct inode *inode) +{ } + static inline int security_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) -- cgit v1.2.3 From 8b9d0b825c6573d654c8b8039ea79920926305c2 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:04 +0100 Subject: security: Introduce inode_post_set_acl hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_set_acl hook. At inode_set_acl hook, EVM verifies the file's existing HMAC value. At inode_post_set_acl, EVM re-calculates the file's HMAC based on the modified POSIX ACL and other file metadata. Other LSMs could similarly take some action after successful POSIX ACL change. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Christian Brauner Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 2 ++ include/linux/security.h | 7 +++++++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 87f60b47dfca..b0125c99f80a 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -157,6 +157,8 @@ LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry, const char *name) LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl) +LSM_HOOK(void, LSM_RET_VOID, inode_post_set_acl, struct dentry *dentry, + const char *acl_name, struct posix_acl *kacl) LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) LSM_HOOK(int, 0, inode_remove_acl, struct mnt_idmap *idmap, diff --git a/include/linux/security.h b/include/linux/security.h index 1cb604282617..c372797e1617 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -372,6 +372,8 @@ int security_inode_setxattr(struct mnt_idmap *idmap, int security_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name, struct posix_acl *kacl); +void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name, + struct posix_acl *kacl); int security_inode_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name); int security_inode_remove_acl(struct mnt_idmap *idmap, @@ -915,6 +917,11 @@ static inline int security_inode_set_acl(struct mnt_idmap *idmap, return 0; } +static inline void security_inode_post_set_acl(struct dentry *dentry, + const char *acl_name, + struct posix_acl *kacl) +{ } + static inline int security_inode_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) -- cgit v1.2.3 From 2d705d8024143c272a764320c880ccd3230bb699 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:05 +0100 Subject: security: Introduce inode_post_remove_acl hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_remove_acl hook. At inode_remove_acl hook, EVM verifies the file's existing HMAC value. At inode_post_remove_acl, EVM re-calculates the file's HMAC with the passed POSIX ACL removed and other file metadata. Other LSMs could similarly take some action after successful POSIX ACL removal. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Acked-by: Christian Brauner Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 2 ++ include/linux/security.h | 8 ++++++++ 2 files changed, 10 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index b0125c99f80a..7e414ba26333 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -163,6 +163,8 @@ LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) LSM_HOOK(int, 0, inode_remove_acl, struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name) +LSM_HOOK(void, LSM_RET_VOID, inode_post_remove_acl, struct mnt_idmap *idmap, + struct dentry *dentry, const char *acl_name) LSM_HOOK(int, 0, inode_need_killpriv, struct dentry *dentry) LSM_HOOK(int, 0, inode_killpriv, struct mnt_idmap *idmap, struct dentry *dentry) diff --git a/include/linux/security.h b/include/linux/security.h index c372797e1617..4b03c76b91f1 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -378,6 +378,9 @@ int security_inode_get_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name); int security_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry, const char *acl_name); +void security_inode_post_remove_acl(struct mnt_idmap *idmap, + struct dentry *dentry, + const char *acl_name); void security_inode_post_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags); int security_inode_getxattr(struct dentry *dentry, const char *name); @@ -936,6 +939,11 @@ static inline int security_inode_remove_acl(struct mnt_idmap *idmap, return 0; } +static inline void security_inode_post_remove_acl(struct mnt_idmap *idmap, + struct dentry *dentry, + const char *acl_name) +{ } + static inline void security_inode_post_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { } -- cgit v1.2.3 From b8d997032a46fcf47d5bda011c0d1e87b20c08ba Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:06 +0100 Subject: security: Introduce key_post_create_or_update hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the key_post_create_or_update hook. Depending on policy, IMA measures the key content after creation or update, so that remote verifiers are aware of the operation. Other LSMs could similarly take some action after successful key creation or update. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu Reviewed-by: Stefan Berger Acked-by: Casey Schaufler Reviewed-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/lsm_hook_defs.h | 3 +++ include/linux/security.h | 11 +++++++++++ 2 files changed, 14 insertions(+) (limited to 'include') diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 7e414ba26333..7e4683035d34 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -405,6 +405,9 @@ LSM_HOOK(void, LSM_RET_VOID, key_free, struct key *key) LSM_HOOK(int, 0, key_permission, key_ref_t key_ref, const struct cred *cred, enum key_need_perm need_perm) LSM_HOOK(int, 0, key_getsecurity, struct key *key, char **buffer) +LSM_HOOK(void, LSM_RET_VOID, key_post_create_or_update, struct key *keyring, + struct key *key, const void *payload, size_t payload_len, + unsigned long flags, bool create) #endif /* CONFIG_KEYS */ #ifdef CONFIG_AUDIT diff --git a/include/linux/security.h b/include/linux/security.h index 4b03c76b91f1..8436f9abf43d 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -2004,6 +2004,9 @@ void security_key_free(struct key *key); int security_key_permission(key_ref_t key_ref, const struct cred *cred, enum key_need_perm need_perm); int security_key_getsecurity(struct key *key, char **_buffer); +void security_key_post_create_or_update(struct key *keyring, struct key *key, + const void *payload, size_t payload_len, + unsigned long flags, bool create); #else @@ -2031,6 +2034,14 @@ static inline int security_key_getsecurity(struct key *key, char **_buffer) return 0; } +static inline void security_key_post_create_or_update(struct key *keyring, + struct key *key, + const void *payload, + size_t payload_len, + unsigned long flags, + bool create) +{ } + #endif #endif /* CONFIG_KEYS */ -- 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 ++++++++++ include/linux/integrity.h | 13 ------------- 2 files changed, 10 insertions(+), 13 deletions(-) (limited to 'include') 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 */ diff --git a/include/linux/integrity.h b/include/linux/integrity.h index 2ea0f2f65ab6..ef0f63ef5ebc 100644 --- a/include/linux/integrity.h +++ b/include/linux/integrity.h @@ -42,17 +42,4 @@ static inline void integrity_load_keys(void) } #endif /* CONFIG_INTEGRITY */ -#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS - -extern int integrity_kernel_module_request(char *kmod_name); - -#else - -static inline int integrity_kernel_module_request(char *kmod_name) -{ - return 0; -} - -#endif /* CONFIG_INTEGRITY_ASYMMETRIC_KEYS */ - #endif /* _LINUX_INTEGRITY_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 ----------------------------------------------- include/uapi/linux/lsm.h | 1 + 2 files changed, 1 insertion(+), 104 deletions(-) (limited to 'include') 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 */ diff --git a/include/uapi/linux/lsm.h b/include/uapi/linux/lsm.h index f8aef9ade549..b3b7fd699b63 100644 --- a/include/uapi/linux/lsm.h +++ b/include/uapi/linux/lsm.h @@ -62,6 +62,7 @@ struct lsm_ctx { #define LSM_ID_LOCKDOWN 108 #define LSM_ID_BPF 109 #define LSM_ID_LANDLOCK 110 +#define LSM_ID_IMA 111 /* * LSM_ATTR_XXX definitions identify different LSM attributes -- 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') 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 From 9238311176115aac1b1a86e8e968c04ebec747a1 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:10 +0100 Subject: evm: Move to LSM infrastructure As for IMA, move hardcoded EVM function calls from various places in the kernel to the LSM infrastructure, by introducing a new LSM named 'evm' (last and always enabled like 'ima'). The order in the Makefile ensures that 'evm' hooks are executed after 'ima' ones. Make EVM functions as static (except for evm_inode_init_security(), which is exported), and register them as hook implementations in init_evm_lsm(). Also move the inline functions evm_inode_remove_acl(), evm_inode_post_remove_acl(), and evm_inode_post_set_acl() from the public evm.h header to evm_main.c. Unlike before (see commit to move IMA to the LSM infrastructure), evm_inode_post_setattr(), evm_inode_post_set_acl(), evm_inode_post_remove_acl(), and evm_inode_post_removexattr() are not executed for private inodes. Finally, add the LSM_ID_EVM case in lsm_list_modules_test.c Signed-off-by: Roberto Sassu Reviewed-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/evm.h | 113 ----------------------------------------------- include/uapi/linux/lsm.h | 1 + 2 files changed, 1 insertion(+), 113 deletions(-) (limited to 'include') diff --git a/include/linux/evm.h b/include/linux/evm.h index 3faabdd47852..cb481eccc967 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -21,45 +21,6 @@ extern enum integrity_status evm_verifyxattr(struct dentry *dentry, void *xattr_value, size_t xattr_value_len, struct integrity_iint_cache *iint); -extern int evm_inode_setattr(struct mnt_idmap *idmap, - struct dentry *dentry, struct iattr *attr); -extern void evm_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry, int ia_valid); -extern int evm_inode_setxattr(struct mnt_idmap *idmap, - struct dentry *dentry, const char *name, - const void *value, size_t size, int flags); -extern void evm_inode_post_setxattr(struct dentry *dentry, - const char *xattr_name, - const void *xattr_value, - size_t xattr_value_len, - int flags); -extern int evm_inode_copy_up_xattr(const char *name); -extern int evm_inode_removexattr(struct mnt_idmap *idmap, - struct dentry *dentry, const char *xattr_name); -extern void evm_inode_post_removexattr(struct dentry *dentry, - const char *xattr_name); -static inline void evm_inode_post_remove_acl(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *acl_name) -{ - evm_inode_post_removexattr(dentry, acl_name); -} -extern int evm_inode_set_acl(struct mnt_idmap *idmap, - struct dentry *dentry, const char *acl_name, - struct posix_acl *kacl); -static inline int evm_inode_remove_acl(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *acl_name) -{ - return evm_inode_set_acl(idmap, dentry, acl_name, NULL); -} -static inline void evm_inode_post_set_acl(struct dentry *dentry, - const char *acl_name, - struct posix_acl *kacl) -{ - return evm_inode_post_setxattr(dentry, acl_name, NULL, 0, 0); -} - int evm_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, struct xattr *xattrs, int *xattr_count); @@ -94,80 +55,6 @@ static inline enum integrity_status evm_verifyxattr(struct dentry *dentry, } #endif -static inline int evm_inode_setattr(struct mnt_idmap *idmap, - struct dentry *dentry, struct iattr *attr) -{ - return 0; -} - -static inline void evm_inode_post_setattr(struct mnt_idmap *idmap, - struct dentry *dentry, int ia_valid) -{ - return; -} - -static inline int evm_inode_setxattr(struct mnt_idmap *idmap, - struct dentry *dentry, const char *name, - const void *value, size_t size, int flags) -{ - return 0; -} - -static inline void evm_inode_post_setxattr(struct dentry *dentry, - const char *xattr_name, - const void *xattr_value, - size_t xattr_value_len, - int flags) -{ - return; -} - -static inline int evm_inode_copy_up_xattr(const char *name) -{ - return 0; -} - -static inline int evm_inode_removexattr(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *xattr_name) -{ - return 0; -} - -static inline void evm_inode_post_removexattr(struct dentry *dentry, - const char *xattr_name) -{ - return; -} - -static inline void evm_inode_post_remove_acl(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *acl_name) -{ - return; -} - -static inline int evm_inode_set_acl(struct mnt_idmap *idmap, - struct dentry *dentry, const char *acl_name, - struct posix_acl *kacl) -{ - return 0; -} - -static inline int evm_inode_remove_acl(struct mnt_idmap *idmap, - struct dentry *dentry, - const char *acl_name) -{ - return 0; -} - -static inline void evm_inode_post_set_acl(struct dentry *dentry, - const char *acl_name, - struct posix_acl *kacl) -{ - return; -} - static inline int evm_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, struct xattr *xattrs, diff --git a/include/uapi/linux/lsm.h b/include/uapi/linux/lsm.h index b3b7fd699b63..33d8c9f4aa6b 100644 --- a/include/uapi/linux/lsm.h +++ b/include/uapi/linux/lsm.h @@ -63,6 +63,7 @@ struct lsm_ctx { #define LSM_ID_BPF 109 #define LSM_ID_LANDLOCK 110 #define LSM_ID_IMA 111 +#define LSM_ID_EVM 112 /* * LSM_ATTR_XXX definitions identify different LSM attributes -- cgit v1.2.3 From 75a323e604fc77c50c7ef2af6f0eeef221637642 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:11 +0100 Subject: evm: Make it independent from 'integrity' LSM Define a new structure for EVM-specific metadata, called evm_iint_cache, and embed it in the inode security blob. Introduce evm_iint_inode() to retrieve metadata, and register evm_inode_alloc_security() for the inode_alloc_security LSM hook, to initialize the structure (before splitting metadata, this task was done by iint_init_always()). Keep the non-NULL checks after calling evm_iint_inode() except in evm_inode_alloc_security(), to take into account inodes for which security_inode_alloc() was not called. When using shared metadata, obtaining a NULL pointer from integrity_iint_find() meant that the file wasn't in the IMA policy. Now, because IMA and EVM use disjoint metadata, the EVM status has to be stored for every inode regardless of the IMA policy. Given that from now on EVM relies on its own metadata, remove the iint parameter from evm_verifyxattr(). Also, directly retrieve the iint in evm_verify_hmac(), called by both evm_verifyxattr() and evm_verify_current_integrity(), since now there is no performance penalty in retrieving EVM metadata (constant time). Replicate the management of the IMA_NEW_FILE flag, by introducing evm_post_path_mknod() and evm_file_release() to respectively set and clear the newly introduced flag EVM_NEW_FILE, at the same time IMA does. Like for IMA, select CONFIG_SECURITY_PATH when EVM is enabled, to ensure that files are marked as new. Unlike ima_post_path_mknod(), evm_post_path_mknod() cannot check if a file must be appraised. Thus, it marks all affected files. Also, it does not clear EVM_NEW_FILE depending on i_version, but that is not a problem because IMA_NEW_FILE is always cleared when set in ima_check_last_writer(). Move the EVM-specific flag EVM_IMMUTABLE_DIGSIG to security/integrity/evm/evm.h, since that definition is now unnecessary in the common integrity layer. Finally, switch to the LSM reservation mechanism for the EVM xattr, and consequently decrement by one the number of xattrs to allocate in security_inode_init_security(). Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/evm.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/linux/evm.h b/include/linux/evm.h index cb481eccc967..d48d6da32315 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -12,15 +12,12 @@ #include #include -struct integrity_iint_cache; - #ifdef CONFIG_EVM extern int evm_set_key(void *key, size_t keylen); extern enum integrity_status evm_verifyxattr(struct dentry *dentry, const char *xattr_name, void *xattr_value, - size_t xattr_value_len, - struct integrity_iint_cache *iint); + size_t xattr_value_len); int evm_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, struct xattr *xattrs, int *xattr_count); @@ -48,8 +45,7 @@ static inline int evm_set_key(void *key, size_t keylen) static inline enum integrity_status evm_verifyxattr(struct dentry *dentry, const char *xattr_name, void *xattr_value, - size_t xattr_value_len, - struct integrity_iint_cache *iint) + size_t xattr_value_len) { return INTEGRITY_UNKNOWN; } -- cgit v1.2.3 From b6c0dec9f78bc691166d60347b52b3adf03d5875 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Thu, 15 Feb 2024 11:31:13 +0100 Subject: integrity: Remove LSM Since now IMA and EVM use their own integrity metadata, it is safe to remove the 'integrity' LSM, with its management of integrity metadata. Keep the iint.c file only for loading IMA and EVM keys at boot, and for creating the integrity directory in securityfs (we need to keep it for retrocompatibility reasons). Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Stefan Berger Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar Signed-off-by: Paul Moore --- include/linux/integrity.h | 14 -------------- 1 file changed, 14 deletions(-) (limited to 'include') diff --git a/include/linux/integrity.h b/include/linux/integrity.h index ef0f63ef5ebc..459b79683783 100644 --- a/include/linux/integrity.h +++ b/include/linux/integrity.h @@ -19,24 +19,10 @@ enum integrity_status { INTEGRITY_UNKNOWN, }; -/* List of EVM protected security xattrs */ #ifdef CONFIG_INTEGRITY -extern struct integrity_iint_cache *integrity_inode_get(struct inode *inode); -extern void integrity_inode_free(struct inode *inode); extern void __init integrity_load_keys(void); #else -static inline struct integrity_iint_cache * - integrity_inode_get(struct inode *inode) -{ - return NULL; -} - -static inline void integrity_inode_free(struct inode *inode) -{ - return; -} - static inline void integrity_load_keys(void) { } -- cgit v1.2.3