diff options
| -rw-r--r-- | include/linux/xattr.h | 2 | ||||
| -rw-r--r-- | security/smack/smack.h | 9 | ||||
| -rw-r--r-- | security/smack/smack_access.c | 52 | ||||
| -rw-r--r-- | security/smack/smack_lsm.c | 269 | ||||
| -rw-r--r-- | security/smack/smackfs.c | 370 |
5 files changed, 524 insertions, 178 deletions
diff --git a/include/linux/xattr.h b/include/linux/xattr.h index e6131ef98d8f..6050783005bd 100644 --- a/include/linux/xattr.h +++ b/include/linux/xattr.h @@ -42,11 +42,13 @@ #define XATTR_SMACK_IPOUT "SMACK64IPOUT" #define XATTR_SMACK_EXEC "SMACK64EXEC" #define XATTR_SMACK_TRANSMUTE "SMACK64TRANSMUTE" +#define XATTR_SMACK_MMAP "SMACK64MMAP" #define XATTR_NAME_SMACK XATTR_SECURITY_PREFIX XATTR_SMACK_SUFFIX #define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN #define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT #define XATTR_NAME_SMACKEXEC XATTR_SECURITY_PREFIX XATTR_SMACK_EXEC #define XATTR_NAME_SMACKTRANSMUTE XATTR_SECURITY_PREFIX XATTR_SMACK_TRANSMUTE +#define XATTR_NAME_SMACKMMAP XATTR_SECURITY_PREFIX XATTR_SMACK_MMAP #define XATTR_CAPS_SUFFIX "capability" #define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX diff --git a/security/smack/smack.h b/security/smack/smack.h index 129c4eb8ffb1..e365d455ceb6 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -52,13 +52,16 @@ struct socket_smack { struct inode_smack { char *smk_inode; /* label of the fso */ char *smk_task; /* label of the task */ + char *smk_mmap; /* label of the mmap domain */ struct mutex smk_lock; /* initialization lock */ int smk_flags; /* smack inode flags */ }; struct task_smack { - char *smk_task; /* label used for access control */ - char *smk_forked; /* label when forked */ + char *smk_task; /* label for access control */ + char *smk_forked; /* label when forked */ + struct list_head smk_rules; /* per task access rules */ + struct mutex smk_rules_lock; /* lock for the rules */ }; #define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ @@ -202,7 +205,7 @@ struct inode_smack *new_inode_smack(char *); /* * These functions are in smack_access.c */ -int smk_access_entry(char *, char *); +int smk_access_entry(char *, char *, struct list_head *); int smk_access(char *, char *, int, struct smk_audit_info *); int smk_curacc(char *, u32, struct smk_audit_info *); int smack_to_cipso(const char *, struct smack_cipso *); diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 7ba8478f599e..86453db4333d 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -70,10 +70,11 @@ int log_policy = SMACK_AUDIT_DENIED; * smk_access_entry - look up matching access rule * @subject_label: a pointer to the subject's Smack label * @object_label: a pointer to the object's Smack label + * @rule_list: the list of rules to search * * This function looks up the subject/object pair in the - * access rule list and returns pointer to the matching rule if found, - * NULL otherwise. + * access rule list and returns the access mode. If no + * entry is found returns -ENOENT. * * NOTE: * Even though Smack labels are usually shared on smack_list @@ -85,13 +86,13 @@ int log_policy = SMACK_AUDIT_DENIED; * will be on the list, so checking the pointers may be a worthwhile * optimization. */ -int smk_access_entry(char *subject_label, char *object_label) +int smk_access_entry(char *subject_label, char *object_label, + struct list_head *rule_list) { - u32 may = MAY_NOT; + int may = -ENOENT; struct smack_rule *srp; - rcu_read_lock(); - list_for_each_entry_rcu(srp, &smack_rule_list, list) { + list_for_each_entry_rcu(srp, rule_list, list) { if (srp->smk_subject == subject_label || strcmp(srp->smk_subject, subject_label) == 0) { if (srp->smk_object == object_label || @@ -101,7 +102,6 @@ int smk_access_entry(char *subject_label, char *object_label) } } } - rcu_read_unlock(); return may; } @@ -129,7 +129,7 @@ int smk_access_entry(char *subject_label, char *object_label) int smk_access(char *subject_label, char *object_label, int request, struct smk_audit_info *a) { - u32 may = MAY_NOT; + int may = MAY_NOT; int rc = 0; /* @@ -181,13 +181,14 @@ int smk_access(char *subject_label, char *object_label, int request, * Beyond here an explicit relationship is required. * If the requested access is contained in the available * access (e.g. read is included in readwrite) it's - * good. - */ - may = smk_access_entry(subject_label, object_label); - /* - * This is a bit map operation. + * good. A negative response from smk_access_entry() + * indicates there is no entry for this pair. */ - if ((request & may) == request) + rcu_read_lock(); + may = smk_access_entry(subject_label, object_label, &smack_rule_list); + rcu_read_unlock(); + + if (may > 0 && (request & may) == request) goto out_audit; rc = -EACCES; @@ -212,12 +213,27 @@ out_audit: */ int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) { + struct task_smack *tsp = current_security(); + char *sp = smk_of_task(tsp); + int may; int rc; - char *sp = smk_of_current(); + /* + * Check the global rule list + */ rc = smk_access(sp, obj_label, mode, NULL); - if (rc == 0) - goto out_audit; + if (rc == 0) { + /* + * If there is an entry in the task's rule list + * it can further restrict access. + */ + may = smk_access_entry(sp, obj_label, &tsp->smk_rules); + if (may < 0) + goto out_audit; + if ((mode & may) == mode) + goto out_audit; + rc = -EACCES; + } /* * Return if a specific label has been designated as the @@ -228,7 +244,7 @@ int smk_curacc(char *obj_label, u32 mode, struct smk_audit_info *a) goto out_audit; if (capable(CAP_MAC_OVERRIDE)) - return 0; + rc = 0; out_audit: #ifdef CONFIG_AUDIT diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 533bf3255d7f..123a499ded37 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -84,6 +84,56 @@ struct inode_smack *new_inode_smack(char *smack) return isp; } +/** + * new_task_smack - allocate a task security blob + * @smack: a pointer to the Smack label to use in the blob + * + * Returns the new blob or NULL if there's no memory available + */ +static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp) +{ + struct task_smack *tsp; + + tsp = kzalloc(sizeof(struct task_smack), gfp); + if (tsp == NULL) + return NULL; + + tsp->smk_task = task; + tsp->smk_forked = forked; + INIT_LIST_HEAD(&tsp->smk_rules); + mutex_init(&tsp->smk_rules_lock); + + return tsp; +} + +/** + * smk_copy_rules - copy a rule set + * @nhead - new rules header pointer + * @ohead - old rules header pointer + * + * Returns 0 on success, -ENOMEM on error + */ +static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead, + gfp_t gfp) +{ + struct smack_rule *nrp; + struct smack_rule *orp; + int rc = 0; + + INIT_LIST_HEAD(nhead); + + list_for_each_entry_rcu(orp, ohead, list) { + nrp = kzalloc(sizeof(struct smack_rule), gfp); + if (nrp == NULL) { + rc = -ENOMEM; + break; + } + *nrp = *orp; + list_add_rcu(&nrp->list, nhead); + } + return rc; +} + /* * LSM hooks. * We he, that is fun! @@ -102,23 +152,17 @@ static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode) { int rc; struct smk_audit_info ad; - char *sp, *tsp; + char *tsp; rc = cap_ptrace_access_check(ctp, mode); if (rc != 0) return rc; - sp = smk_of_current(); tsp = smk_of_task(task_security(ctp)); smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); smk_ad_setfield_u_tsk(&ad, ctp); - /* we won't log here, because rc can be overriden */ - rc = smk_access(sp, tsp, MAY_READWRITE, NULL); - if (rc != 0 && capable(CAP_MAC_OVERRIDE)) - rc = 0; - - smack_log(sp, tsp, MAY_READWRITE, rc, &ad); + rc = smk_curacc(tsp, MAY_READWRITE, &ad); return rc; } @@ -134,23 +178,17 @@ static int smack_ptrace_traceme(struct task_struct *ptp) { int rc; struct smk_audit_info ad; - char *sp, *tsp; + char *tsp; rc = cap_ptrace_traceme(ptp); if (rc != 0) return rc; + tsp = smk_of_task(task_security(ptp)); smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); smk_ad_setfield_u_tsk(&ad, ptp); - sp = smk_of_current(); - tsp = smk_of_task(task_security(ptp)); - /* we won't log here, because rc can be overriden */ - rc = smk_access(tsp, sp, MAY_READWRITE, NULL); - if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE)) - rc = 0; - - smack_log(tsp, sp, MAY_READWRITE, rc, &ad); + rc = smk_curacc(tsp, MAY_READWRITE, &ad); return rc; } @@ -474,7 +512,7 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, { char *isp = smk_of_inode(inode); char *dsp = smk_of_inode(dir); - u32 may; + int may; if (name) { *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL); @@ -483,14 +521,17 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, } if (value) { - may = smk_access_entry(smk_of_current(), dsp); + rcu_read_lock(); + may = smk_access_entry(smk_of_current(), dsp, &smack_rule_list); + rcu_read_unlock(); /* * If the access rule allows transmutation and * the directory requests transmutation then * by all means transmute. */ - if (((may & MAY_TRANSMUTE) != 0) && smk_inode_transmutable(dir)) + if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && + smk_inode_transmutable(dir)) isp = dsp; *value = kstrdup(isp, GFP_KERNEL); @@ -716,7 +757,8 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name, if (strcmp(name, XATTR_NAME_SMACK) == 0 || strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || - strcmp(name, XATTR_NAME_SMACKEXEC) == 0) { + strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || + strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { if (!capable(CAP_MAC_ADMIN)) rc = -EPERM; /* @@ -773,6 +815,12 @@ static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, isp->smk_task = nsp; else isp->smk_task = smack_known_invalid.smk_known; + } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { + nsp = smk_import(value, size); + if (nsp != NULL) + isp->smk_mmap = nsp; + else + isp->smk_mmap = smack_known_invalid.smk_known; } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) isp->smk_flags |= SMK_INODE_TRANSMUTE; @@ -815,7 +863,8 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || - strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { + strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 || + strcmp(name, XATTR_NAME_SMACKMMAP)) { if (!capable(CAP_MAC_ADMIN)) rc = -EPERM; } else @@ -829,6 +878,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name) if (rc == 0) { isp = dentry->d_inode->i_security; isp->smk_task = NULL; + isp->smk_mmap = NULL; } return rc; @@ -1060,6 +1110,113 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, } /** + * smk_mmap_list_check - the mmap check + * @sub: subject label + * @obj: object label + * @access: access mode + * @local: the task specific rule list + * + * Returns 0 if acces is permitted, -EACCES otherwise + */ +static int smk_mmap_list_check(char *sub, char *obj, int access, + struct list_head *local) +{ + int may; + + /* + * If there is not a global rule that + * allows access say no. + */ + may = smk_access_entry(sub, obj, &smack_rule_list); + if (may == -ENOENT || (may & access) != access) + return -EACCES; + /* + * If there is a task local rule that + * denies access say no. + */ + may = smk_access_entry(sub, obj, local); + if (may != -ENOENT && (may & access) != access) + return -EACCES; + + return 0; +} + +/** + * smack_file_mmap : + * Check permissions for a mmap operation. The @file may be NULL, e.g. + * if mapping anonymous memory. + * @file contains the file structure for file to map (may be NULL). + * @reqprot contains the protection requested by the application. + * @prot contains the protection that will be applied by the kernel. + * @flags contains the operational flags. + * Return 0 if permission is granted. + */ +static int smack_file_mmap(struct file *file, + unsigned long reqprot, unsigned long prot, + unsigned long flags, unsigned long addr, + unsigned long addr_only) +{ + struct smack_rule *srp; + struct task_smack *tsp; + char *sp; + char *msmack; + struct inode_smack *isp; + struct dentry *dp; + int rc; + + /* do DAC check on address space usage */ + rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only); + if (rc || addr_only) + return rc; + + if (file == NULL || file->f_dentry == NULL) + return 0; + + dp = file->f_dentry; + + if (dp->d_inode == NULL) + return 0; + + isp = dp->d_inode->i_security; + if (isp->smk_mmap == NULL) + return 0; + msmack = isp->smk_mmap; + + tsp = current_security(); + sp = smk_of_current(); + rc = 0; + + rcu_read_lock(); + /* + * For each Smack rule associated with the subject + * label verify that the SMACK64MMAP also has access + * to that rule's object label. + * + * Because neither of the labels comes + * from the networking code it is sufficient + * to compare pointers. + */ + list_for_each_entry_rcu(srp, &smack_rule_list, list) { + if (srp->smk_subject != sp) + continue; + /* + * Matching labels always allows access. + */ + if (msmack == srp->smk_object) + continue; + + rc = smk_mmap_list_check(msmack, srp->smk_object, + srp->smk_access, &tsp->smk_rules); + if (rc != 0) + break; + } + + rcu_read_unlock(); + + return rc; +} + +/** * smack_file_set_fowner - set the file security blob value * @file: object in question * @@ -1095,6 +1252,7 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, * struct fown_struct is never outside the context of a struct file */ file = container_of(fown, struct file, f_owner); + /* we don't log here as rc can be overriden */ rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL); if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) @@ -1145,9 +1303,14 @@ static int smack_file_receive(struct file *file) */ static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) { - cred->security = kzalloc(sizeof(struct task_smack), gfp); - if (cred->security == NULL) + struct task_smack *tsp; + + tsp = new_task_smack(NULL, NULL, gfp); + if (tsp == NULL) return -ENOMEM; + + cred->security = tsp; + return 0; } @@ -1156,13 +1319,24 @@ static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) * smack_cred_free - "free" task-level security credentials * @cred: the credentials in question * - * Smack isn't using copies of blobs. Everyone - * points to an immutable list. The blobs never go away. - * There is no leak here. */ static void smack_cred_free(struct cred *cred) { - kfree(cred->security); + struct task_smack *tsp = cred->security; + struct smack_rule *rp; + struct list_head *l; + struct list_head *n; + + if (tsp == NULL) + return; + cred->security = NULL; + + list_for_each_safe(l, n, &tsp->smk_rules) { + rp = list_entry(l, struct smack_rule, list); + list_del(&rp->list); + kfree(rp); + } + kfree(tsp); } /** @@ -1178,13 +1352,16 @@ static int smack_cred_prepare(struct cred *new, const struct cred *old, { struct task_smack *old_tsp = old->security; struct task_smack *new_tsp; + int rc; - new_tsp = kzalloc(sizeof(struct task_smack), gfp); + new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp); if (new_tsp == NULL) return -ENOMEM; - new_tsp->smk_task = old_tsp->smk_task; - new_tsp->smk_forked = old_tsp->smk_task; + rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp); + if (rc != 0) + return rc; + new->security = new_tsp; return 0; } @@ -1203,6 +1380,11 @@ static void smack_cred_transfer(struct cred *new, const struct cred *old) new_tsp->smk_task = old_tsp->smk_task; new_tsp->smk_forked = old_tsp->smk_task; + mutex_init(&new_tsp->smk_rules_lock); + INIT_LIST_HEAD(&new_tsp->smk_rules); + + + /* cbs copy rule list */ } /** @@ -2419,6 +2601,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) } } isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp); + isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp); dput(dp); break; @@ -2478,6 +2661,7 @@ static int smack_getprocattr(struct task_struct *p, char *name, char **value) static int smack_setprocattr(struct task_struct *p, char *name, void *value, size_t size) { + int rc; struct task_smack *tsp; struct task_smack *oldtsp; struct cred *new; @@ -2513,13 +2697,16 @@ static int smack_setprocattr(struct task_struct *p, char *name, new = prepare_creds(); if (new == NULL) return -ENOMEM; - tsp = kzalloc(sizeof(struct task_smack), GFP_KERNEL); + + tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL); if (tsp == NULL) { kfree(new); return -ENOMEM; } - tsp->smk_task = newsmack; - tsp->smk_forked = oldtsp->smk_forked; + rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL); + if (rc != 0) + return rc; + new->security = tsp; commit_creds(new); return size; @@ -3221,6 +3408,7 @@ struct security_operations smack_ops = { .file_ioctl = smack_file_ioctl, .file_lock = smack_file_lock, .file_fcntl = smack_file_fcntl, + .file_mmap = smack_file_mmap, .file_set_fowner = smack_file_set_fowner, .file_send_sigiotask = smack_file_send_sigiotask, .file_receive = smack_file_receive, @@ -3334,23 +3522,20 @@ static __init int smack_init(void) struct cred *cred; struct task_smack *tsp; - tsp = kzalloc(sizeof(struct task_smack), GFP_KERNEL); + if (!security_module_enable(&smack_ops)) + return 0; + + tsp = new_task_smack(smack_known_floor.smk_known, + smack_known_floor.smk_known, GFP_KERNEL); if (tsp == NULL) return -ENOMEM; - if (!security_module_enable(&smack_ops)) { - kfree(tsp); - return 0; - } - printk(KERN_INFO "Smack: Initializing.\n"); /* * Set the security state for the initial task. */ cred = (struct cred *) current->cred; - tsp->smk_forked = smack_known_floor.smk_known; - tsp->smk_task = smack_known_floor.smk_known; cred->security = tsp; /* initialize the smack_know_list */ diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 362d5eda948b..90d1bbaaa6f3 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -43,6 +43,7 @@ enum smk_inos { SMK_NETLBLADDR = 8, /* single label hosts */ SMK_ONLYCAP = 9, /* the only "capable" label */ SMK_LOGGING = 10, /* logging */ + SMK_LOAD_SELF = 11, /* task specific rules */ }; /* @@ -135,104 +136,30 @@ static void smk_netlabel_audit_set(struct netlbl_audit *nap) #define SMK_NETLBLADDRMIN 9 #define SMK_NETLBLADDRMAX 42 -/* - * Seq_file read operations for /smack/load - */ - -static void *load_seq_start(struct seq_file *s, loff_t *pos) -{ - if (*pos == SEQ_READ_FINISHED) - return NULL; - if (list_empty(&smack_rule_list)) - return NULL; - return smack_rule_list.next; -} - -static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) -{ - struct list_head *list = v; - - if (list_is_last(list, &smack_rule_list)) { - *pos = SEQ_READ_FINISHED; - return NULL; - } - return list->next; -} - -static int load_seq_show(struct seq_file *s, void *v) -{ - struct list_head *list = v; - struct smack_rule *srp = - list_entry(list, struct smack_rule, list); - - seq_printf(s, "%s %s", (char *)srp->smk_subject, - (char *)srp->smk_object); - - seq_putc(s, ' '); - - if (srp->smk_access & MAY_READ) - seq_putc(s, 'r'); - if (srp->smk_access & MAY_WRITE) - seq_putc(s, 'w'); - if (srp->smk_access & MAY_EXEC) - seq_putc(s, 'x'); - if (srp->smk_access & MAY_APPEND) - seq_putc(s, 'a'); - if (srp->smk_access & MAY_TRANSMUTE) - seq_putc(s, 't'); - if (srp->smk_access == 0) - seq_putc(s, '-'); - - seq_putc(s, '\n'); - - return 0; -} - -static void load_seq_stop(struct seq_file *s, void *v) -{ - /* No-op */ -} - -static const struct seq_operations load_seq_ops = { - .start = load_seq_start, - .next = load_seq_next, - .show = load_seq_show, - .stop = load_seq_stop, -}; - -/** - * smk_open_load - open() for /smack/load - * @inode: inode structure representing file - * @file: "load" file pointer - * - * For reading, use load_seq_* seq_file reading operations. - */ -static int smk_open_load(struct inode *inode, struct file *file) -{ - return seq_open(file, &load_seq_ops); -} - /** * smk_set_access - add a rule to the rule list * @srp: the new rule to add + * @rule_list: the list of rules + * @rule_lock: the rule list lock * * Looks through the current subject/object/access list for * the subject/object pair and replaces the access that was * there. If the pair isn't found add it with the specified * access. * + * Returns 1 if a rule was found to exist already, 0 if it is new * Returns 0 if nothing goes wrong or -ENOMEM if it fails * during the allocation of the new pair to add. */ -static int smk_set_access(struct smack_rule *srp) +static int smk_set_access(struct smack_rule *srp, struct list_head *rule_list, + struct mutex *rule_lock) { struct smack_rule *sp; - int ret = 0; - int found; - mutex_lock(&smack_list_lock); + int found = 0; - found = 0; - list_for_each_entry_rcu(sp, &smack_rule_list, list) { + mutex_lock(rule_lock); + + list_for_each_entry_rcu(sp, rule_list, list) { if (sp->smk_subject == srp->smk_subject && sp->smk_object == srp->smk_object) { found = 1; @@ -241,19 +168,21 @@ static int smk_set_access(struct smack_rule *srp) } } if (found == 0) - list_add_rcu(&srp->list, &smack_rule_list); + list_add_rcu(&srp->list, rule_list); - mutex_unlock(&smack_list_lock); + mutex_unlock(rule_lock); - return ret; + return found; } /** - * smk_write_load - write() for /smack/load + * smk_write_load_list - write() for any /smack/load * @file: file pointer, not actually used * @buf: where to get the data from * @count: bytes sent * @ppos: where to start - must be 0 + * @rule_list: the list of rules to write to + * @rule_lock: lock for the rule list * * Get one smack access rule from above. * The format is exactly: @@ -263,21 +192,19 @@ static int smk_set_access(struct smack_rule *srp) * * writes must be SMK_LABELLEN+SMK_LABELLEN+SMK_ACCESSLEN bytes. */ -static ssize_t smk_write_load(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) +static ssize_t smk_write_load_list(struct file *file, const char __user *buf, + size_t count, loff_t *ppos, + struct list_head *rule_list, + struct mutex *rule_lock) { struct smack_rule *rule; char *data; int rc = -EINVAL; /* - * Must have privilege. * No partial writes. * Enough data must be present. */ - if (!capable(CAP_MAC_ADMIN)) - return -EPERM; - if (*ppos != 0) return -EINVAL; /* @@ -372,11 +299,13 @@ static ssize_t smk_write_load(struct file *file, const char __user *buf, goto out_free_rule; } - rc = smk_set_access(rule); - - if (!rc) - rc = count; - goto out; + rc = count; + /* + * smk_set_access returns true if there was already a rule + * for the subject/object pair, and false if it was new. + */ + if (!smk_set_access(rule, rule_list, rule_lock)) + goto out; out_free_rule: kfree(rule); @@ -385,6 +314,108 @@ out: return rc; } + +/* + * Seq_file read operations for /smack/load + */ + +static void *load_seq_start(struct seq_file *s, loff_t *pos) +{ + if (*pos == SEQ_READ_FINISHED) + return NULL; + if (list_empty(&smack_rule_list)) + return NULL; + return smack_rule_list.next; +} + +static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct list_head *list = v; + + if (list_is_last(list, &smack_rule_list)) { + *pos = SEQ_READ_FINISHED; + return NULL; + } + return list->next; +} + +static int load_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_rule *srp = + list_entry(list, struct smack_rule, list); + + seq_printf(s, "%s %s", (char *)srp->smk_subject, + (char *)srp->smk_object); + + seq_putc(s, ' '); + + if (srp->smk_access & MAY_READ) + seq_putc(s, 'r'); + if (srp->smk_access & MAY_WRITE) + seq_putc(s, 'w'); + if (srp->smk_access & MAY_EXEC) + seq_putc(s, 'x'); + if (srp->smk_access & MAY_APPEND) + seq_putc(s, 'a'); + if (srp->smk_access & MAY_TRANSMUTE) + seq_putc(s, 't'); + if (srp->smk_access == 0) + seq_putc(s, '-'); + + seq_putc(s, '\n'); + + return 0; +} + +static void load_seq_stop(struct seq_file *s, void *v) +{ + /* No-op */ +} + +static const struct seq_operations load_seq_ops = { + .start = load_seq_start, + .next = load_seq_next, + .show = load_seq_show, + .stop = load_seq_stop, +}; + +/** + * smk_open_load - open() for /smack/load + * @inode: inode structure representing file + * @file: "load" file pointer + * + * For reading, use load_seq_* seq_file reading operations. + */ +static int smk_open_load(struct inode *inode, struct file *file) +{ + return seq_open(file, &load_seq_ops); +} + +/** + * smk_write_load - write() for /smack/load + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_load(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + + /* + * Must have privilege. + * No partial writes. + * Enough data must be present. + */ + if (!capable(CAP_MAC_ADMIN)) + return -EPERM; + + return smk_write_load_list(file, buf, count, ppos, &smack_rule_list, + &smack_list_lock); +} + static const struct file_operations smk_load_ops = { .open = smk_open_load, .read = seq_read, @@ -1288,6 +1319,112 @@ static const struct file_operations smk_logging_ops = { .write = smk_write_logging, .llseek = default_llseek, }; + +/* + * Seq_file read operations for /smack/load-self + */ + +static void *load_self_seq_start(struct seq_file *s, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + + if (*pos == SEQ_READ_FINISHED) + return NULL; + if (list_empty(&tsp->smk_rules)) + return NULL; + return tsp->smk_rules.next; +} + +static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + struct task_smack *tsp = current_security(); + struct list_head *list = v; + + if (list_is_last(list, &tsp->smk_rules)) { + *pos = SEQ_READ_FINISHED; + return NULL; + } + return list->next; +} + +static int load_self_seq_show(struct seq_file *s, void *v) +{ + struct list_head *list = v; + struct smack_rule *srp = + list_entry(list, struct smack_rule, list); + + seq_printf(s, "%s %s", (char *)srp->smk_subject, + (char *)srp->smk_object); + + seq_putc(s, ' '); + + if (srp->smk_access & MAY_READ) + seq_putc(s, 'r'); + if (srp->smk_access & MAY_WRITE) + seq_putc(s, 'w'); + if (srp->smk_access & MAY_EXEC) + seq_putc(s, 'x'); + if (srp->smk_access & MAY_APPEND) + seq_putc(s, 'a'); + if (srp->smk_access & MAY_TRANSMUTE) + seq_putc(s, 't'); + if (srp->smk_access == 0) + seq_putc(s, '-'); + + seq_putc(s, '\n'); + + return 0; +} + +static void load_self_seq_stop(struct seq_file *s, void *v) +{ + /* No-op */ +} + +static const struct seq_operations load_self_seq_ops = { + .start = load_self_seq_start, + .next = load_self_seq_next, + .show = load_self_seq_show, + .stop = load_self_seq_stop, +}; + + +/** + * smk_open_load_self - open() for /smack/load-self + * @inode: inode structure representing file + * @file: "load" file pointer + * + * For reading, use load_seq_* seq_file reading operations. + */ +static int smk_open_load_self(struct inode *inode, struct file *file) +{ + return seq_open(file, &load_self_seq_ops); +} + +/** + * smk_write_load_self - write() for /smack/load-self + * @file: file pointer, not actually used + * @buf: where to get the data from + * @count: bytes sent + * @ppos: where to start - must be 0 + * + */ +static ssize_t smk_write_load_self(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct task_smack *tsp = current_security(); + + return smk_write_load_list(file, buf, count, ppos, &tsp->smk_rules, + &tsp->smk_rules_lock); +} + +static const struct file_operations smk_load_self_ops = { + .open = smk_open_load_self, + .read = seq_read, + .llseek = seq_lseek, + .write = smk_write_load_self, + .release = seq_release, +}; /** * smk_fill_super - fill the /smackfs superblock * @sb: the empty superblock @@ -1304,23 +1441,26 @@ static int smk_fill_super(struct super_block *sb, void *data, int silent) struct inode *root_inode; static struct tree_descr smack_files[] = { - [SMK_LOAD] = - {"load", &smk_load_ops, S_IRUGO|S_IWUSR}, - [SMK_CIPSO] = - {"cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR}, - [SMK_DOI] = - {"doi", &smk_doi_ops, S_IRUGO|S_IWUSR}, - [SMK_DIRECT] = - {"direct", &smk_direct_ops, S_IRUGO|S_IWUSR}, - [SMK_AMBIENT] = - {"ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR}, - [SMK_NETLBLADDR] = - {"netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR}, - [SMK_ONLYCAP] = - {"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR}, - [SMK_LOGGING] = - {"logging", &smk_logging_ops, S_IRUGO|S_IWUSR}, - /* last one */ {""} + [SMK_LOAD] = { + "load", &smk_load_ops, S_IRUGO|S_IWUSR}, + [SMK_CIPSO] = { + "cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR}, + [SMK_DOI] = { + "doi", &smk_doi_ops, S_IRUGO|S_IWUSR}, + [SMK_DIRECT] = { + "direct", &smk_direct_ops, S_IRUGO|S_IWUSR}, + [SMK_AMBIENT] = { + "ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR}, + [SMK_NETLBLADDR] = { + "netlabel", &smk_netlbladdr_ops, S_IRUGO|S_IWUSR}, + [SMK_ONLYCAP] = { + "onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR}, + [SMK_LOGGING] = { + "logging", &smk_logging_ops, S_IRUGO|S_IWUSR}, + [SMK_LOAD_SELF] = { + "load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO}, + /* last one */ + {""} }; rc = simple_fill_super(sb, SMACK_MAGIC, smack_files); |