From 8a076191f373abaeb4aa5f6755d22e49db98940f Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Sat, 1 Mar 2008 21:51:09 +0200 Subject: LSM: Introduce inode_getsecid and ipc_getsecid hooks Introduce inode_getsecid(inode, secid) and ipc_getsecid(ipcp, secid) LSM hooks. These hooks will be used instead of similar exported SELinux interfaces. Let {inode,ipc,task}_getsecid hooks set the secid to 0 by default if CONFIG_SECURITY is not defined or if the hook is set to NULL (dummy). This is done to notify the caller that no valid secid exists. Signed-off-by: Casey Schaufler Signed-off-by: Ahmed S. Darwish Acked-by: James Morris Reviewed-by: Paul Moore --- include/linux/security.h | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index c673dfd4dffc..45717d9d9656 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -468,6 +468,11 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @dentry is the dentry being changed. * Return 0 on success. If error is returned, then the operation * causing setuid bit removal is failed. + * @inode_getsecid: + * Get the secid associated with the node. + * @inode contains a pointer to the inode. + * @secid contains a pointer to the location where result will be saved. + * In case of failure, @secid will be set to zero. * * Security hooks for file operations * @@ -636,6 +641,8 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @task_getsecid: * Retrieve the security identifier of the process @p. * @p contains the task_struct for the process and place is into @secid. + * In case of failure, @secid will be set to zero. + * * @task_setgroups: * Check permission before setting the supplementary group set of the * current process. @@ -997,6 +1004,11 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @ipcp contains the kernel IPC permission structure * @flag contains the desired (requested) permission set * Return 0 if permission is granted. + * @ipc_getsecid: + * Get the secid associated with the ipc object. + * @ipcp contains the kernel IPC permission structure. + * @secid contains a pointer to the location where result will be saved. + * In case of failure, @secid will be set to zero. * * Security hooks for individual messages held in System V IPC message queues * @msg_msg_alloc_security: @@ -1317,6 +1329,7 @@ struct security_operations { int (*inode_getsecurity)(const struct inode *inode, const char *name, void **buffer, bool alloc); int (*inode_setsecurity)(struct inode *inode, const char *name, const void *value, size_t size, int flags); int (*inode_listsecurity)(struct inode *inode, char *buffer, size_t buffer_size); + void (*inode_getsecid)(const struct inode *inode, u32 *secid); int (*file_permission) (struct file * file, int mask); int (*file_alloc_security) (struct file * file); @@ -1369,6 +1382,7 @@ struct security_operations { void (*task_to_inode)(struct task_struct *p, struct inode *inode); int (*ipc_permission) (struct kern_ipc_perm * ipcp, short flag); + void (*ipc_getsecid) (struct kern_ipc_perm *ipcp, u32 *secid); int (*msg_msg_alloc_security) (struct msg_msg * msg); void (*msg_msg_free_security) (struct msg_msg * msg); @@ -1578,6 +1592,7 @@ int security_inode_killpriv(struct dentry *dentry); int security_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc); int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags); int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size); +void security_inode_getsecid(const struct inode *inode, u32 *secid); int security_file_permission(struct file *file, int mask); int security_file_alloc(struct file *file); void security_file_free(struct file *file); @@ -1622,6 +1637,7 @@ int security_task_prctl(int option, unsigned long arg2, unsigned long arg3, void security_task_reparent_to_init(struct task_struct *p); void security_task_to_inode(struct task_struct *p, struct inode *inode); int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag); +void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid); int security_msg_msg_alloc(struct msg_msg *msg); void security_msg_msg_free(struct msg_msg *msg); int security_msg_queue_alloc(struct msg_queue *msq); @@ -2022,6 +2038,11 @@ static inline int security_inode_listsecurity(struct inode *inode, char *buffer, return 0; } +static inline void security_inode_getsecid(const struct inode *inode, u32 *secid) +{ + *secid = 0; +} + static inline int security_file_permission (struct file *file, int mask) { return 0; @@ -2137,7 +2158,9 @@ static inline int security_task_getsid (struct task_struct *p) } static inline void security_task_getsecid (struct task_struct *p, u32 *secid) -{ } +{ + *secid = 0; +} static inline int security_task_setgroups (struct group_info *group_info) { @@ -2216,6 +2239,11 @@ static inline int security_ipc_permission (struct kern_ipc_perm *ipcp, return 0; } +static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid) +{ + *secid = 0; +} + static inline int security_msg_msg_alloc (struct msg_msg * msg) { return 0; -- cgit v1.2.2 From 03d37d25e0f91b28c4b6d002be6221f1af4b19d8 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Sat, 1 Mar 2008 22:00:05 +0200 Subject: LSM/Audit: Introduce generic Audit LSM hooks Introduce a generic Audit interface for security modules by adding the following new LSM hooks: audit_rule_init(field, op, rulestr, lsmrule) audit_rule_known(krule) audit_rule_match(secid, field, op, rule, actx) audit_rule_free(rule) Those hooks are only available if CONFIG_AUDIT is enabled. Signed-off-by: Casey Schaufler Signed-off-by: Ahmed S. Darwish Acked-by: James Morris Reviewed-by: Paul Moore --- include/linux/security.h | 72 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index 45717d9d9656..697f228daf19 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -37,6 +37,7 @@ extern unsigned securebits; struct ctl_table; +struct audit_krule; /* * These functions are in security/capability.c and are used @@ -1235,6 +1236,37 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @secdata contains the security context. * @seclen contains the length of the security context. * + * Security hooks for Audit + * + * @audit_rule_init: + * Allocate and initialize an LSM audit rule structure. + * @field contains the required Audit action. Fields flags are defined in include/linux/audit.h + * @op contains the operator the rule uses. + * @rulestr contains the context where the rule will be applied to. + * @lsmrule contains a pointer to receive the result. + * Return 0 if @lsmrule has been successfully set, + * -EINVAL in case of an invalid rule. + * + * @audit_rule_known: + * Specifies whether given @rule contains any fields related to current LSM. + * @rule contains the audit rule of interest. + * Return 1 in case of relation found, 0 otherwise. + * + * @audit_rule_match: + * Determine if given @secid matches a rule previously approved + * by @audit_rule_known. + * @secid contains the security id in question. + * @field contains the field which relates to current LSM. + * @op contains the operator that will be used for matching. + * @rule points to the audit rule that will be checked against. + * @actx points to the audit context associated with the check. + * Return 1 if secid matches the rule, 0 if it does not, -ERRNO on failure. + * + * @audit_rule_free: + * Deallocate the LSM audit rule structure previously allocated by + * audit_rule_init. + * @rule contains the allocated rule + * * This is the main security structure. */ struct security_operations { @@ -1494,6 +1526,13 @@ struct security_operations { #endif /* CONFIG_KEYS */ +#ifdef CONFIG_AUDIT + int (*audit_rule_init)(u32 field, u32 op, char *rulestr, void **lsmrule); + int (*audit_rule_known)(struct audit_krule *krule); + int (*audit_rule_match)(u32 secid, u32 field, u32 op, void *lsmrule, + struct audit_context *actx); + void (*audit_rule_free)(void *lsmrule); +#endif /* CONFIG_AUDIT */ }; /* prototypes */ @@ -2700,5 +2739,38 @@ static inline int security_key_permission(key_ref_t key_ref, #endif #endif /* CONFIG_KEYS */ +#ifdef CONFIG_AUDIT +#ifdef CONFIG_SECURITY +int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule); +int security_audit_rule_known(struct audit_krule *krule); +int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule, + struct audit_context *actx); +void security_audit_rule_free(void *lsmrule); + +#else + +static inline int security_audit_rule_init(u32 field, u32 op, char *rulestr, + void **lsmrule) +{ + return 0; +} + +static inline int security_audit_rule_known(struct audit_krule *krule) +{ + return 0; +} + +static inline int security_audit_rule_match(u32 secid, u32 field, u32 op, + void *lsmrule, struct audit_context *actx) +{ + return 0; +} + +static inline void security_audit_rule_free(void *lsmrule) +{ } + +#endif /* CONFIG_SECURITY */ +#endif /* CONFIG_AUDIT */ + #endif /* ! __LINUX_SECURITY_H */ -- cgit v1.2.2 From 076c54c5bcaed2081c0cba94a6f77c4d470236ad Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Thu, 6 Mar 2008 18:09:10 +0200 Subject: Security: Introduce security= boot parameter Add the security= boot parameter. This is done to avoid LSM registration clashes in case of more than one bult-in module. User can choose a security module to enable at boot. If no security= boot parameter is specified, only the first LSM asking for registration will be loaded. An invalid security module name will be treated as if no module has been chosen. LSM modules must check now if they are allowed to register by calling security_module_enable(ops) first. Modify SELinux and SMACK to do so. Do not let SMACK register smackfs if it was not chosen on boot. Smackfs assumes that smack hooks are registered and the initial task security setup (swapper->security) is done. Signed-off-by: Ahmed S. Darwish Acked-by: James Morris --- include/linux/security.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/linux/security.h') diff --git a/include/linux/security.h b/include/linux/security.h index 697f228daf19..f4116d6ed64b 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -36,6 +36,9 @@ extern unsigned securebits; +/* Maximum number of letters for an LSM name string */ +#define SECURITY_NAME_MAX 10 + struct ctl_table; struct audit_krule; @@ -137,6 +140,12 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) /** * struct security_operations - main security structure * + * Security module identifier. + * + * @name: + * A string that acts as a unique identifeir for the LSM with max number + * of characters = SECURITY_NAME_MAX. + * * Security hooks for program execution operations. * * @bprm_alloc_security: @@ -1270,6 +1279,8 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * This is the main security structure. */ struct security_operations { + char name[SECURITY_NAME_MAX + 1]; + int (*ptrace) (struct task_struct * parent, struct task_struct * child); int (*capget) (struct task_struct * target, kernel_cap_t * effective, @@ -1537,6 +1548,7 @@ struct security_operations { /* prototypes */ extern int security_init (void); +extern int security_module_enable(struct security_operations *ops); extern int register_security (struct security_operations *ops); extern int mod_reg_security (const char *name, struct security_operations *ops); extern struct dentry *securityfs_create_file(const char *name, mode_t mode, -- cgit v1.2.2