diff options
| -rw-r--r-- | security/selinux/avc.c | 415 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 42 | ||||
| -rw-r--r-- | security/selinux/include/avc.h | 6 | ||||
| -rw-r--r-- | security/selinux/include/security.h | 32 | ||||
| -rw-r--r-- | security/selinux/ss/avtab.c | 104 | ||||
| -rw-r--r-- | security/selinux/ss/avtab.h | 33 | ||||
| -rw-r--r-- | security/selinux/ss/conditional.c | 32 | ||||
| -rw-r--r-- | security/selinux/ss/conditional.h | 6 | ||||
| -rw-r--r-- | security/selinux/ss/policydb.c | 5 | ||||
| -rw-r--r-- | security/selinux/ss/services.c | 213 | ||||
| -rw-r--r-- | security/selinux/ss/services.h | 6 |
11 files changed, 834 insertions, 60 deletions
diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 3c17dda9571d..2d5e1b04cd50 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -22,6 +22,7 @@ #include <linux/init.h> #include <linux/skbuff.h> #include <linux/percpu.h> +#include <linux/list.h> #include <net/sock.h> #include <linux/un.h> #include <net/af_unix.h> @@ -48,6 +49,7 @@ struct avc_entry { u32 tsid; u16 tclass; struct av_decision avd; + struct avc_xperms_node *xp_node; }; struct avc_node { @@ -56,6 +58,16 @@ struct avc_node { struct rcu_head rhead; }; +struct avc_xperms_decision_node { + struct extended_perms_decision xpd; + struct list_head xpd_list; /* list of extended_perms_decision */ +}; + +struct avc_xperms_node { + struct extended_perms xp; + struct list_head xpd_head; /* list head of extended_perms_decision */ +}; + struct avc_cache { struct hlist_head slots[AVC_CACHE_SLOTS]; /* head for avc_node->list */ spinlock_t slots_lock[AVC_CACHE_SLOTS]; /* lock for writes */ @@ -80,6 +92,9 @@ DEFINE_PER_CPU(struct avc_cache_stats, avc_cache_stats) = { 0 }; static struct avc_cache avc_cache; static struct avc_callback_node *avc_callbacks; static struct kmem_cache *avc_node_cachep; +static struct kmem_cache *avc_xperms_data_cachep; +static struct kmem_cache *avc_xperms_decision_cachep; +static struct kmem_cache *avc_xperms_cachep; static inline int avc_hash(u32 ssid, u32 tsid, u16 tclass) { @@ -170,7 +185,17 @@ void __init avc_init(void) atomic_set(&avc_cache.lru_hint, 0); avc_node_cachep = kmem_cache_create("avc_node", sizeof(struct avc_node), - 0, SLAB_PANIC, NULL); + 0, SLAB_PANIC, NULL); + avc_xperms_cachep = kmem_cache_create("avc_xperms_node", + sizeof(struct avc_xperms_node), + 0, SLAB_PANIC, NULL); + avc_xperms_decision_cachep = kmem_cache_create( + "avc_xperms_decision_node", + sizeof(struct avc_xperms_decision_node), + 0, SLAB_PANIC, NULL); + avc_xperms_data_cachep = kmem_cache_create("avc_xperms_data", + sizeof(struct extended_perms_data), + 0, SLAB_PANIC, NULL); audit_log(current->audit_context, GFP_KERNEL, AUDIT_KERNEL, "AVC INITIALIZED\n"); } @@ -205,9 +230,261 @@ int avc_get_hash_stats(char *page) slots_used, AVC_CACHE_SLOTS, max_chain_len); } +/* + * using a linked list for extended_perms_decision lookup because the list is + * always small. i.e. less than 5, typically 1 + */ +static struct extended_perms_decision *avc_xperms_decision_lookup(u8 driver, + struct avc_xperms_node *xp_node) +{ + struct avc_xperms_decision_node *xpd_node; + + list_for_each_entry(xpd_node, &xp_node->xpd_head, xpd_list) { + if (xpd_node->xpd.driver == driver) + return &xpd_node->xpd; + } + return NULL; +} + +static inline unsigned int +avc_xperms_has_perm(struct extended_perms_decision *xpd, + u8 perm, u8 which) +{ + unsigned int rc = 0; + + if ((which == XPERMS_ALLOWED) && + (xpd->used & XPERMS_ALLOWED)) + rc = security_xperm_test(xpd->allowed->p, perm); + else if ((which == XPERMS_AUDITALLOW) && + (xpd->used & XPERMS_AUDITALLOW)) + rc = security_xperm_test(xpd->auditallow->p, perm); + else if ((which == XPERMS_DONTAUDIT) && + (xpd->used & XPERMS_DONTAUDIT)) + rc = security_xperm_test(xpd->dontaudit->p, perm); + return rc; +} + +static void avc_xperms_allow_perm(struct avc_xperms_node *xp_node, + u8 driver, u8 perm) +{ + struct extended_perms_decision *xpd; + security_xperm_set(xp_node->xp.drivers.p, driver); + xpd = avc_xperms_decision_lookup(driver, xp_node); + if (xpd && xpd->allowed) + security_xperm_set(xpd->allowed->p, perm); +} + +static void avc_xperms_decision_free(struct avc_xperms_decision_node *xpd_node) +{ + struct extended_perms_decision *xpd; + + xpd = &xpd_node->xpd; + if (xpd->allowed) + kmem_cache_free(avc_xperms_data_cachep, xpd->allowed); + if (xpd->auditallow) + kmem_cache_free(avc_xperms_data_cachep, xpd->auditallow); + if (xpd->dontaudit) + kmem_cache_free(avc_xperms_data_cachep, xpd->dontaudit); + kmem_cache_free(avc_xperms_decision_cachep, xpd_node); +} + +static void avc_xperms_free(struct avc_xperms_node *xp_node) +{ + struct avc_xperms_decision_node *xpd_node, *tmp; + + if (!xp_node) + return; + + list_for_each_entry_safe(xpd_node, tmp, &xp_node->xpd_head, xpd_list) { + list_del(&xpd_node->xpd_list); + avc_xperms_decision_free(xpd_node); + } + kmem_cache_free(avc_xperms_cachep, xp_node); +} + +static void avc_copy_xperms_decision(struct extended_perms_decision *dest, + struct extended_perms_decision *src) +{ + dest->driver = src->driver; + dest->used = src->used; + if (dest->used & XPERMS_ALLOWED) + memcpy(dest->allowed->p, src->allowed->p, + sizeof(src->allowed->p)); + if (dest->used & XPERMS_AUDITALLOW) + memcpy(dest->auditallow->p, src->auditallow->p, + sizeof(src->auditallow->p)); + if (dest->used & XPERMS_DONTAUDIT) + memcpy(dest->dontaudit->p, src->dontaudit->p, + sizeof(src->dontaudit->p)); +} + +/* + * similar to avc_copy_xperms_decision, but only copy decision + * information relevant to this perm + */ +static inline void avc_quick_copy_xperms_decision(u8 perm, + struct extended_perms_decision *dest, + struct extended_perms_decision *src) +{ + /* + * compute index of the u32 of the 256 bits (8 u32s) that contain this + * command permission + */ + u8 i = perm >> 5; + + dest->used = src->used; + if (dest->used & XPERMS_ALLOWED) + dest->allowed->p[i] = src->allowed->p[i]; + if (dest->used & XPERMS_AUDITALLOW) + dest->auditallow->p[i] = src->auditallow->p[i]; + if (dest->used & XPERMS_DONTAUDIT) + dest->dontaudit->p[i] = src->dontaudit->p[i]; +} + +static struct avc_xperms_decision_node + *avc_xperms_decision_alloc(u8 which) +{ + struct avc_xperms_decision_node *xpd_node; + struct extended_perms_decision *xpd; + + xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep, + GFP_ATOMIC | __GFP_NOMEMALLOC); + if (!xpd_node) + return NULL; + + xpd = &xpd_node->xpd; + if (which & XPERMS_ALLOWED) { + xpd->allowed = kmem_cache_zalloc(avc_xperms_data_cachep, + GFP_ATOMIC | __GFP_NOMEMALLOC); + if (!xpd->allowed) + goto error; + } + if (which & XPERMS_AUDITALLOW) { + xpd->auditallow = kmem_cache_zalloc(avc_xperms_data_cachep, + GFP_ATOMIC | __GFP_NOMEMALLOC); + if (!xpd->auditallow) + goto error; + } + if (which & XPERMS_DONTAUDIT) { + xpd->dontaudit = kmem_cache_zalloc(avc_xperms_data_cachep, + GFP_ATOMIC | __GFP_NOMEMALLOC); + if (!xpd->dontaudit) + goto error; + } + return xpd_node; +error: + avc_xperms_decision_free(xpd_node); + return NULL; +} + +static int avc_add_xperms_decision(struct avc_node *node, + struct extended_perms_decision *src) +{ + struct avc_xperms_decision_node *dest_xpd; + + node->ae.xp_node->xp.len++; + dest_xpd = avc_xperms_decision_alloc(src->used); + if (!dest_xpd) + return -ENOMEM; + avc_copy_xperms_decision(&dest_xpd->xpd, src); + list_add(&dest_xpd->xpd_list, &node->ae.xp_node->xpd_head); + return 0; +} + +static struct avc_xperms_node *avc_xperms_alloc(void) +{ + struct avc_xperms_node *xp_node; + + xp_node = kmem_cache_zalloc(avc_xperms_cachep, + GFP_ATOMIC|__GFP_NOMEMALLOC); + if (!xp_node) + return xp_node; + INIT_LIST_HEAD(&xp_node->xpd_head); + return xp_node; +} + +static int avc_xperms_populate(struct avc_node *node, + struct avc_xperms_node *src) +{ + struct avc_xperms_node *dest; + struct avc_xperms_decision_node *dest_xpd; + struct avc_xperms_decision_node *src_xpd; + + if (src->xp.len == 0) + return 0; + dest = avc_xperms_alloc(); + if (!dest) + return -ENOMEM; + + memcpy(dest->xp.drivers.p, src->xp.drivers.p, sizeof(dest->xp.drivers.p)); + dest->xp.len = src->xp.len; + + /* for each source xpd allocate a destination xpd and copy */ + list_for_each_entry(src_xpd, &src->xpd_head, xpd_list) { + dest_xpd = avc_xperms_decision_alloc(src_xpd->xpd.used); + if (!dest_xpd) + goto error; + avc_copy_xperms_decision(&dest_xpd->xpd, &src_xpd->xpd); + list_add(&dest_xpd->xpd_list, &dest->xpd_head); + } + node->ae.xp_node = dest; + return 0; +error: + avc_xperms_free(dest); + return -ENOMEM; + +} + +static inline u32 avc_xperms_audit_required(u32 requested, + struct av_decision *avd, + struct extended_perms_decision *xpd, + u8 perm, + int result, + u32 *deniedp) +{ + u32 denied, audited; + + denied = requested & ~avd->allowed; + if (unlikely(denied)) { + audited = denied & avd->auditdeny; + if (audited && xpd) { + if (avc_xperms_has_perm(xpd, perm, XPERMS_DONTAUDIT)) + audited &= ~requested; + } + } else if (result) { + audited = denied = requested; + } else { + audited = requested & avd->auditallow; + if (audited && xpd) { + if (!avc_xperms_has_perm(xpd, perm, XPERMS_AUDITALLOW)) + audited &= ~requested; + } + } + + *deniedp = denied; + return audited; +} + +static inline int avc_xperms_audit(u32 ssid, u32 tsid, u16 tclass, + u32 requested, struct av_decision *avd, + struct extended_perms_decision *xpd, + u8 perm, int result, + struct common_audit_data *ad) +{ + u32 audited, denied; + + audited = avc_xperms_audit_required( + requested, avd, xpd, perm, result, &denied); + if (likely(!audited)) + return 0; + return slow_avc_audit(ssid, tsid, tclass, requested, + audited, denied, result, ad, 0); +} + static void avc_node_free(struct rcu_head *rhead) { struct avc_node *node = container_of(rhead, struct avc_node, rhead); + avc_xperms_free(node->ae.xp_node); kmem_cache_free(avc_node_cachep, node); avc_cache_stats_incr(frees); } @@ -221,6 +498,7 @@ static void avc_node_delete(struct avc_node *node) static void avc_node_kill(struct avc_node *node) { + avc_xperms_free(node->ae.xp_node); kmem_cache_free(avc_node_cachep, node); avc_cache_stats_incr(frees); atomic_dec(&avc_cache.active_nodes); @@ -367,6 +645,7 @@ static int avc_latest_notif_update(int seqno, int is_insert) * @tsid: target security identifier * @tclass: target security class * @avd: resulting av decision + * @xp_node: resulting extended permissions * * Insert an AVC entry for the SID pair * (@ssid, @tsid) and class @tclass. @@ -378,7 +657,9 @@ static int avc_latest_notif_update(int seqno, int is_insert) * the access vectors into a cache entry, returns * avc_node inserted. Otherwise, this function returns NULL. */ -static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass, struct av_decision *avd) +static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass, + struct av_decision *avd, + struct avc_xperms_node *xp_node) { struct avc_node *pos, *node = NULL; int hvalue; @@ -391,10 +672,15 @@ static struct avc_node *avc_insert(u32 ssid, u32 tsid, u16 tclass, struct av_dec if (node) { struct hlist_head *head; spinlock_t *lock; + int rc = 0; hvalue = avc_hash(ssid, tsid, tclass); avc_node_populate(node, ssid, tsid, tclass, avd); - + rc = avc_xperms_populate(node, xp_node); + if (rc) { + kmem_cache_free(avc_node_cachep, node); + return NULL; + } head = &avc_cache.slots[hvalue]; lock = &avc_cache.slots_lock[hvalue]; @@ -523,14 +809,17 @@ out: * @perms : Permission mask bits * @ssid,@tsid,@tclass : identifier of an AVC entry * @seqno : sequence number when decision was made + * @xpd: extended_perms_decision to be added to the node * * if a valid AVC entry doesn't exist,this function returns -ENOENT. * if kmalloc() called internal returns NULL, this function returns -ENOMEM. * otherwise, this function updates the AVC entry. The original AVC-entry object * will release later by RCU. */ -static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass, - u32 seqno) +static int avc_update_node(u32 event, u32 perms, u8 driver, u8 xperm, u32 ssid, + u32 tsid, u16 tclass, u32 seqno, + struct extended_perms_decision *xpd, + u32 flags) { int hvalue, rc = 0; unsigned long flag; @@ -574,9 +863,19 @@ static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass, avc_node_populate(node, ssid, tsid, tclass, &orig->ae.avd); + if (orig->ae.xp_node) { + rc = avc_xperms_populate(node, orig->ae.xp_node); + if (rc) { + kmem_cache_free(avc_node_cachep, node); + goto out_unlock; + } + } + switch (event) { case AVC_CALLBACK_GRANT: node->ae.avd.allowed |= perms; + if (node->ae.xp_node && (flags & AVC_EXTENDED_PERMS)) + avc_xperms_allow_perm(node->ae.xp_node, driver, xperm); break; case AVC_CALLBACK_TRY_REVOKE: case AVC_CALLBACK_REVOKE: @@ -594,6 +893,9 @@ static int avc_update_node(u32 event, u32 perms, u32 ssid, u32 tsid, u16 tclass, case AVC_CALLBACK_AUDITDENY_DISABLE: node->ae.avd.auditdeny &= ~perms; break; + case AVC_CALLBACK_ADD_XPERMS: + avc_add_xperms_decision(node, xpd); + break; } avc_node_replace(node, orig); out_unlock: @@ -665,18 +967,20 @@ int avc_ss_reset(u32 seqno) * results in a bigger stack frame. */ static noinline struct avc_node *avc_compute_av(u32 ssid, u32 tsid, - u16 tclass, struct av_decision *avd) + u16 tclass, struct av_decision *avd, + struct avc_xperms_node *xp_node) { rcu_read_unlock(); - security_compute_av(ssid, tsid, tclass, avd); + INIT_LIST_HEAD(&xp_node->xpd_head); + security_compute_av(ssid, tsid, tclass, avd, &xp_node->xp); rcu_read_lock(); - return avc_insert(ssid, tsid, tclass, avd); + return avc_insert(ssid, tsid, tclass, avd, xp_node); } static noinline int avc_denied(u32 ssid, u32 tsid, - u16 tclass, u32 requested, - unsigned flags, - struct av_decision *avd) + u16 tclass, u32 requested, + u8 driver, u8 xperm, unsigned flags, + struct av_decision *avd) { if (flags & AVC_STRICT) return -EACCES; @@ -684,11 +988,91 @@ static noinline int avc_denied(u32 ssid, u32 tsid, if (selinux_enforcing && !(avd->flags & AVD_FLAGS_PERMISSIVE)) return -EACCES; - avc_update_node(AVC_CALLBACK_GRANT, requested, ssid, - tsid, tclass, avd->seqno); + avc_update_node(AVC_CALLBACK_GRANT, requested, driver, xperm, ssid, + tsid, tclass, avd->seqno, NULL, flags); return 0; } +/* + * The avc extended permissions logic adds an additional 256 bits of + * permissions to an avc node when extended permissions for that node are + * specified in the avtab. If the additional 256 permissions is not adequate, + * as-is the case with ioctls, then multiple may be chained together and the + * driver field is used to specify which set contains the permission. + */ +int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested, + u8 driver, u8 xperm, struct common_audit_data *ad) +{ + struct avc_node *node; + struct av_decision avd; + u32 denied; + struct extended_perms_decision local_xpd; + struct extended_perms_decision *xpd = NULL; + struct extended_perms_data allowed; + struct extended_perms_data auditallow; + struct extended_perms_data dontaudit; + struct avc_xperms_node local_xp_node; + struct avc_xperms_node *xp_node; + int rc = 0, rc2; + + xp_node = &local_xp_node; + BUG_ON(!requested); + + rcu_read_lock(); + + node = avc_lookup(ssid, tsid, tclass); + if (unlikely(!node)) { + node = avc_compute_av(ssid, tsid, tclass, &avd, xp_node); + } else { + memcpy(&avd, &node->ae.avd, sizeof(avd)); + xp_node = node->ae.xp_node; + } + /* if extended permissions are not defined, only consider av_decision */ + if (!xp_node || !xp_node->xp.len) + goto decision; + + local_xpd.allowed = &allowed; + local_xpd.auditallow = &auditallow; + local_xpd.dontaudit = &dontaudit; + + xpd = avc_xperms_decision_lookup(driver, xp_node); + if (unlikely(!xpd)) { + /* + * Compute the extended_perms_decision only if the driver + * is flagged + */ + if (!security_xperm_test(xp_node->xp.drivers.p, driver)) { + avd.allowed &= ~requested; + goto decision; + } + rcu_read_unlock(); + security_compute_xperms_decision(ssid, tsid, tclass, driver, + &local_xpd); + rcu_read_lock(); + avc_update_node(AVC_CALLBACK_ADD_XPERMS, requested, driver, xperm, + ssid, tsid, tclass, avd.seqno, &local_xpd, 0); + } else { + avc_quick_copy_xperms_decision(xperm, &local_xpd, xpd); + } + xpd = &local_xpd; + + if (!avc_xperms_has_perm(xpd, xperm, XPERMS_ALLOWED)) + avd.allowed &= ~requested; + +decision: + denied = requested & ~(avd.allowed); + if (unlikely(denied)) + rc = avc_denied(ssid, tsid, tclass, requested, driver, xperm, + AVC_EXTENDED_PERMS, &avd); + + rcu_read_unlock(); + + rc2 = avc_xperms_audit(ssid, tsid, tclass, requested, + &avd, xpd, xperm, rc, ad); + if (rc2) + return rc2; + return rc; +} /** * avc_has_perm_noaudit - Check permissions but perform no auditing. @@ -716,6 +1100,7 @@ inline int avc_has_perm_noaudit(u32 ssid, u32 tsid, struct av_decision *avd) { struct avc_node *node; + struct avc_xperms_node xp_node; int rc = 0; u32 denied; @@ -725,13 +1110,13 @@ inline int avc_has_perm_noaudit(u32 ssid, u32 tsid, node = avc_lookup(ssid, tsid, tclass); if (unlikely(!node)) - node = avc_compute_av(ssid, tsid, tclass, avd); + node = avc_compute_av(ssid, tsid, tclass, avd, &xp_node); else memcpy(avd, &node->ae.avd, sizeof(*avd)); denied = requested & ~(avd->allowed); if (unlikely(denied)) - rc = avc_denied(ssid, tsid, tclass, requested, flags, avd); + rc = avc_denied(ssid, tsid, tclass, requested, 0, 0, flags, avd); rcu_read_unlock(); return rc; diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 692e3cc8ce23..a049b7216270 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3216,6 +3216,46 @@ static void selinux_file_free_security(struct file *file) file_free_security(file); } +/* + * Check whether a task has the ioctl permission and cmd + * operation to an inode. + */ +int ioctl_has_perm(const struct cred *cred, struct file *file, + u32 requested, u16 cmd) +{ + struct common_audit_data ad; + struct file_security_struct *fsec = file->f_security; + struct inode *inode = file_inode(file); + struct inode_security_struct *isec = inode->i_security; + struct lsm_ioctlop_audit ioctl; + u32 ssid = cred_sid(cred); + int rc; + u8 driver = cmd >> 8; + u8 xperm = cmd & 0xff; + + ad.type = LSM_AUDIT_DATA_IOCTL_OP; + ad.u.op = &ioctl; + ad.u.op->cmd = cmd; + ad.u.op->path = file->f_path; + + if (ssid != fsec->sid) { + rc = avc_has_perm(ssid, fsec->sid, + SECCLASS_FD, + FD__USE, + &ad); + if (rc) + goto out; + } + + if (unlikely(IS_PRIVATE(inode))) + return 0; + + rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, + requested, driver, xperm, &ad); +out: + return rc; +} + static int selinux_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -3258,7 +3298,7 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd, * to the file's ioctl() function. */ default: - error = file_has_perm(cred, file, FILE__IOCTL); + error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd); } return error; } diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h index ddf8eec03f21..db12ff14277b 100644 --- a/security/selinux/include/avc.h +++ b/security/selinux/include/avc.h @@ -142,6 +142,7 @@ static inline int avc_audit(u32 ssid, u32 tsid, } #define AVC_STRICT 1 /* Ignore permissive mode. */ +#define AVC_EXTENDED_PERMS 2 /* update extended permissions */ int avc_has_perm_noaudit(u32 ssid, u32 tsid, u16 tclass, u32 requested, unsigned flags, @@ -151,6 +152,10 @@ int avc_has_perm(u32 ssid, u32 tsid, u16 tclass, u32 requested, struct common_audit_data *auditdata); +int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested, + u8 driver, u8 perm, struct common_audit_data *ad); + + u32 avc_policy_seqno(void); #define AVC_CALLBACK_GRANT 1 @@ -161,6 +166,7 @@ u32 avc_policy_seqno(void); #define AVC_CALLBACK_AUDITALLOW_DISABLE 32 #define AVC_CALLBACK_AUDITDENY_ENABLE 64 #define AVC_CALLBACK_AUDITDENY_DISABLE 128 +#define AVC_CALLBACK_ADD_XPERMS 256 int avc_add_callback(int (*callback)(u32 event), u32 events); diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 36993ad1c067..6a681d26bf20 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -35,13 +35,14 @@ #define POLICYDB_VERSION_NEW_OBJECT_DEFAULTS 27 #define POLICYDB_VERSION_DEFAULT_TYPE 28 #define POLICYDB_VERSION_CONSTRAINT_NAMES 29 +#define POLICYDB_VERSION_XPERMS_IOCTL 30 /* Range of policy versions we understand*/ #define POLICYDB_VERSION_MIN POLICYDB_VERSION_BASE #ifdef CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX #define POLICYDB_VERSION_MAX CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX_VALUE #else -#define POLICYDB_VERSION_MAX POLICYDB_VERSION_CONSTRAINT_NAMES +#define POLICYDB_VERSION_MAX POLICYDB_VERSION_XPERMS_IOCTL #endif /* Mask for just the mount related flags */ @@ -109,11 +110,38 @@ struct av_decision { u32 flags; }; +#define XPERMS_ALLOWED 1 +#define XPERMS_AUDITALLOW 2 +#define XPERMS_DONTAUDIT 4 + +#define security_xperm_set(perms, x) (perms[x >> 5] |= 1 << (x & 0x1f)) +#define security_xperm_test(perms, x) (1 & (perms[x >> 5] >> (x & 0x1f))) +struct extended_perms_data { + u32 p[8]; +}; + +struct extended_perms_decision { + u8 used; + u8 driver; + struct extended_perms_data *allowed; + struct extended_perms_data *auditallow; + struct extended_perms_data *dontaudit; +}; + +struct extended_perms { + u16 len; /* length associated decision chain */ + struct extended_perms_data drivers; /* flag drivers that are used */ +}; + /* definitions of av_decision.flags */ #define AVD_FLAGS_PERMISSIVE 0x0001 void security_compute_av(u32 ssid, u32 tsid, - u16 tclass, struct av_decision *avd); + u16 tclass, struct av_decision *avd, + struct extended_perms *xperms); + +void security_compute_xperms_decision(u32 ssid, u32 tsid, u16 tclass, + u8 driver, struct extended_perms_decision *xpermd); void security_compute_av_user(u32 ssid, u32 tsid, u16 tclass, struct av_decision *avd); diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index b64f2772b030..3628d3a868b6 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -24,6 +24,7 @@ #include "policydb.h" static struct kmem_cache *avtab_node_cachep; +static struct kmem_cache *avtab_xperms_cachep; /* Based on MurmurHash3, written by Austin Appleby and placed in the * public domain. @@ -70,11 +71,24 @@ avtab_insert_node(struct avtab *h, int hvalue, struct avtab_key *key, struct avtab_datum *datum) { struct avtab_node *newnode; + struct avtab_extended_perms *xperms; newnode = kmem_cache_zalloc(avtab_node_cachep, GFP_KERNEL); if (newnode == NULL) return NULL; newnode->key = *key; - newnode->datum = *datum; + + if (key->specified & AVTAB_XPERMS) { + xperms = kmem_cache_zalloc(avtab_xperms_cachep, GFP_KERNEL); + if (xperms == NULL) { + kmem_cache_free(avtab_node_cachep, newnode); + return NULL; + } + *xperms = *(datum->u.xperms); + newnode->datum.u.xperms = xperms; + } else { + newnode->datum.u.data = datum->u.data; + } + if (prev) { newnode->next = prev->next; prev->next = newnode; @@ -107,8 +121,12 @@ static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_dat if (key->source_type == cur->key.source_type && key->target_type == cur->key.target_type && key->target_class == cur->key.target_class && - (specified & cur->key.specified)) + (specified & cur->key.specified)) { + /* extended perms may not be unique */ + if (specified & AVTAB_XPERMS) + break; return -EEXIST; + } if (key->source_type < cur->key.source_type) break; if (key->source_type == cur->key.source_type && @@ -271,6 +289,9 @@ void avtab_destroy(struct avtab *h) while (cur) { temp = cur; cur = cur->next; + if (temp->key.specified & AVTAB_XPERMS) + kmem_cache_free(avtab_xperms_cachep, + temp->datum.u.xperms); kmem_cache_free(avtab_node_cachep, temp); } } @@ -359,7 +380,10 @@ static uint16_t spec_order[] = { AVTAB_AUDITALLOW, AVTAB_TRANSITION, AVTAB_CHANGE, - AVTAB_MEMBER + AVTAB_MEMBER, + AVTAB_XPERMS_ALLOWED, + AVTAB_XPERMS_AUDITALLOW, + AVTAB_XPERMS_DONTAUDIT }; int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, @@ -369,10 +393,11 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, { __le16 buf16[4]; u16 enabled; - __le32 buf32[7]; u32 items, items2, val, vers = pol->policyvers; struct avtab_key key; struct avtab_datum datum; + struct avtab_extended_perms xperms; + __le32 buf32[ARRAY_SIZE(xperms.perms.p)]; int i, rc; unsigned set; @@ -429,11 +454,15 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, printk(KERN_ERR "SELinux: avtab: entry has both access vectors and types\n"); return -EINVAL; } + if (val & AVTAB_XPERMS) { + printk(KERN_ERR "SELinux: avtab: entry has extended permissions\n"); + return -EINVAL; + } for (i = 0; i < ARRAY_SIZE(spec_order); i++) { if (val & spec_order[i]) { key.specified = spec_order[i] | enabled; - datum.data = le32_to_cpu(buf32[items++]); + datum.u.data = le32_to_cpu(buf32[items++]); rc = insertf(a, &key, &datum, p); if (rc) return rc; @@ -476,14 +505,42 @@ int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, return -EINVAL; } - rc = next_entry(buf32, fp, sizeof(u32)); - if (rc) { - printk(KERN_ERR "SELinux: avtab: truncated entry\n"); - return rc; + if ((vers < POLICYDB_VERSION_XPERMS_IOCTL) && + (key.specified & AVTAB_XPERMS)) { + printk(KERN_ERR "SELinux: avtab: policy version %u does not " + "support extended permissions rules and one " + "was specified\n", vers); + return -EINVAL; + } else if (key.specified & AVTAB_XPERMS) { + memset(&xperms, 0, sizeof(struct avtab_extended_perms)); + rc = next_entry(&xperms.specified, fp, sizeof(u8)); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + rc = next_entry(&xperms.driver, fp, sizeof(u8)); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + rc = next_entry(buf32, fp, sizeof(u32)*ARRAY_SIZE(xperms.perms.p)); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + for (i = 0; i < ARRAY_SIZE(xperms.perms.p); i++) + xperms.perms.p[i] = le32_to_cpu(buf32[i]); + datum.u.xperms = &xperms; + } else { + rc = next_entry(buf32, fp, sizeof(u32)); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + datum.u.data = le32_to_cpu(*buf32); } - datum.data = le32_to_cpu(*buf32); if ((key.specified & AVTAB_TYPE) && - !policydb_type_isvalid(pol, datum.data)) { + !policydb_type_isvalid(pol, datum.u.data)) { printk(KERN_ERR "SELinux: avtab: invalid type\n"); return -EINVAL; } @@ -543,8 +600,9 @@ bad: int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp) { __le16 buf16[4]; - __le32 buf32[1]; + __le32 buf32[ARRAY_SIZE(cur->datum.u.xperms->perms.p)]; int rc; + unsigned int i; buf16[0] = cpu_to_le16(cur->key.source_type); buf16[1] = cpu_to_le16(cur->key.target_type); @@ -553,8 +611,22 @@ int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp) rc = put_entry(buf16, sizeof(u16), 4, fp); if (rc) return rc; - buf32[0] = cpu_to_le32(cur->datum.data); - rc = put_entry(buf32, sizeof(u32), 1, fp); + + if (cur->key.specified & AVTAB_XPERMS) { + rc = put_entry(&cur->datum.u.xperms->specified, sizeof(u8), 1, fp); + if (rc) + return rc; + rc = put_entry(&cur->datum.u.xperms->driver, sizeof(u8), 1, fp); + if (rc) + return rc; + for (i = 0; i < ARRAY_SIZE(cur->datum.u.xperms->perms.p); i++) + buf32[i] = cpu_to_le32(cur->datum.u.xperms->perms.p[i]); + rc = put_entry(buf32, sizeof(u32), + ARRAY_SIZE(cur->datum.u.xperms->perms.p), fp); + } else { + buf32[0] = cpu_to_le32(cur->datum.u.data); + rc = put_entry(buf32, sizeof(u32), 1, fp); + } if (rc) return rc; return 0; @@ -588,9 +660,13 @@ void avtab_cache_init(void) avtab_node_cachep = kmem_cache_create("avtab_node", sizeof(struct avtab_node), 0, SLAB_PANIC, NULL); + avtab_xperms_cachep = kmem_cache_create("avtab_extended_perms", + sizeof(struct avtab_extended_perms), + 0, SLAB_PANIC, NULL); } void avtab_cache_destroy(void) { kmem_cache_destroy(avtab_node_cachep); + kmem_cache_destroy(avtab_xperms_cachep); } diff --git a/security/selinux/ss/avtab.h b/security/selinux/ss/avtab.h index adb451cd44f9..d946c9dc3c9c 100644 --- a/security/selinux/ss/avtab.h +++ b/security/selinux/ss/avtab.h @@ -23,6 +23,7 @@ #ifndef _SS_AVTAB_H_ #define _SS_AVTAB_H_ +#include "security.h" #include <linux/flex_array.h> struct avtab_key { @@ -37,13 +38,43 @@ struct avtab_key { #define AVTAB_MEMBER 0x0020 #define AVTAB_CHANGE 0x0040 #define AVTAB_TYPE (AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE) +/* extended permissions */ +#define AVTAB_XPERMS_ALLOWED 0x0100 +#define AVTAB_XPERMS_AUDITALLOW 0x0200 +#define AVTAB_XPERMS_DONTAUDIT 0x0400 +#define AVTAB_XPERMS (AVTAB_XPERMS_ALLOWED | \ + AVTAB_XPERMS_AUDITALLOW | \ + AVTAB_XPERMS_DONTAUDIT) #define AVTAB_ENABLED_OLD 0x80000000 /* reserved for used in cond_avtab */ #define AVTAB_ENABLED 0x8000 /* reserved for used in cond_avtab */ u16 specified; /* what field is specified */ }; +/* + * For operations that require more than the 32 permissions provided by the avc + * extended permissions may be used to provide 256 bits of permissions. + */ +struct avtab_extended_perms { +/* These are not flags. All 256 values may be used */ +#define AVTAB_XPERMS_IOCTLFUNCTION 0x01 +#define AVTAB_XPERMS_IOCTLDRIVER 0x02 + /* extension of the avtab_key specified */ + u8 specified; /* ioctl, netfilter, ... */ + /* + * if 256 bits is not adequate as is often the case with ioctls, then + * multiple extended perms may be used and the driver field + * specifies which permissions are included. + */ + u8 driver; + /* 256 bits of permissions */ + struct extended_perms_data perms; +}; + struct avtab_datum { - u32 data; /* access vector or type value */ + union { + u32 data; /* access vector or type value */ + struct avtab_extended_perms *xperms; + } u; }; struct avtab_node { diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index 62c6773be0b7..18643bf9894d 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -15,6 +15,7 @@ #include "security.h" #include "conditional.h" +#include "services.h" /* * cond_evaluate_expr evaluates a conditional expr @@ -612,21 +613,39 @@ int cond_write_list(struct policydb *p, struct cond_node *list, void *fp) return 0; } + +void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key, + struct extended_perms_decision *xpermd) +{ + struct avtab_node *node; + + if (!ctab || !key || !xpermd) + return; + + for (node = avtab_search_node(ctab, key); node; + node = avtab_search_node_next(node, key->specified)) { + if (node->key.specified & AVTAB_ENABLED) + services_compute_xperms_decision(xpermd, node); + } + return; + +} /* Determine whether additional permissions are granted by the conditional * av table, and if so, add them to the result */ -void cond_compute_av(struct avtab *ctab, struct avtab_key *key, struct av_decision *avd) +void cond_compute_av(struct avtab *ctab, struct avtab_key *key, + struct av_decision *avd, struct extended_perms *xperms) { struct avtab_node *node; - if (!ctab || !key || !avd) + if (!ctab || !key || !avd || !xperms) return; for (node = avtab_search_node(ctab, key); node; node = avtab_search_node_next(node, key->specified)) { if ((u16)(AVTAB_ALLOWED|AVTAB_ENABLED) == (node->key.specified & (AVTAB_ALLOWED|AVTAB_ENABLED))) - avd->allowed |= node->datum.data; + avd->allowed |= node->datum.u.data; if ((u16)(AVTAB_AUDITDENY|AVTAB_ENABLED) == (node->key.specified & (AVTAB_AUDITDENY|AVTAB_ENABLED))) /* Since a '0' in an auditdeny mask represents a @@ -634,10 +653,13 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key, struct av_decisi * the '&' operand to ensure that all '0's in the mask * are retained (much unlike the allow and auditallow cases). */ - avd->auditdeny &= node->datum.data; + avd->auditdeny &= node->datum.u.data; if ((u16)(AVTAB_AUDITALLOW|AVTAB_ENABLED) == (node->key.specified & (AVTAB_AUDITALLOW|AVTAB_ENABLED))) - avd->auditallow |= node->datum.data; + avd->auditallow |= node->datum.u.data; + if ((node->key.specified & AVTAB_ENABLED) && + (node->key.specified & AVTAB_XPERMS)) + services_compute_xperms_drivers(xperms, node); } return; } diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h index 4d1f87466508..ddb43e7e1c75 100644 --- a/security/selinux/ss/conditional.h +++ b/security/selinux/ss/conditional.h @@ -73,8 +73,10 @@ int cond_read_list(struct policydb *p, void *fp); int cond_write_bool(void *key, void *datum, void *ptr); int cond_write_list(struct policydb *p, struct cond_node *list, void *fp); -void cond_compute_av(struct avtab *ctab, struct avtab_key *key, struct av_decision *avd); - +void cond_compute_av(struct avtab *ctab, struct avtab_key *key, + struct av_decision *avd, struct extended_perms *xperms); +void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key, + struct extended_perms_decision *xpermd); int evaluate_cond_node(struct policydb *p, struct cond_node *node); #endif /* _CONDITIONAL_H_ */ diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index 74aa224267c1..992a31530825 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -148,6 +148,11 @@ static struct policydb_compat_info policydb_compat[] = { .sym_num = SYM_NUM, .ocon_num = OCON_NUM, }, + { + .version = POLICYDB_VERSION_XPERMS_IOCTL, + .sym_num = SYM_NUM, + .ocon_num = OCON_NUM, + }, }; static struct policydb_compat_info *policydb_lookup_compat(int version) diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 9e2d82070915..b7df12ba61d8 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -93,9 +93,10 @@ static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len); static void context_struct_compute_av(struct context *scontext, - struct context *tcontext, - u16 tclass, - struct av_decision *avd); + struct context *tcontext, + u16 tclass, + struct av_decision *avd, + struct extended_perms *xperms); struct selinux_mapping { u16 value; /* policy value */ @@ -565,7 +566,8 @@ static void type_attribute_bounds_av(struct context *scontext, context_struct_compute_av(&lo_scontext, tcontext, tclass, - &lo_avd); + &lo_avd, + NULL); if ((lo_avd.allowed & avd->allowed) == avd->allowed) return; /* no masked permission */ masked = ~lo_avd.allowed & avd->allowed; @@ -580,7 +582,8 @@ static void type_attribute_bounds_av(struct context *scontext, context_struct_compute_av(scontext, &lo_tcontext, tclass, - &lo_avd); + &lo_avd, + NULL); if ((lo_avd.allowed & avd->allowed) == avd->allowed) return; /* no masked permission */ masked = ~lo_avd.allowed & avd->allowed; @@ -596,7 +599,8 @@ static void type_attribute_bounds_av(struct context *scontext, context_struct_compute_av(&lo_scontext, &lo_tcontext, tclass, - &lo_avd); + &lo_avd, + NULL); if ((lo_avd.allowed & avd->allowed) == avd->allowed) return; /* no masked permission */ masked = ~lo_avd.allowed & avd->allowed; @@ -613,13 +617,39 @@ static void type_attribute_bounds_av(struct context *scontext, } /* - * Compute access vectors based on a context structure pair for - * the permissions in a particular class. + * flag which drivers have permissions + * only looking for ioctl based extended permssions + */ +void services_compute_xperms_drivers( + struct extended_perms *xperms, + struct avtab_node *node) +{ + unsigned int i; + + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { + /* if one or more driver has all permissions allowed */ + for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++) + xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i]; + } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { + /* if allowing permissions within a driver */ + security_xperm_set(xperms->drivers.p, + node->datum.u.xperms->driver); + } + + /* If no ioctl commands are allowed, ignore auditallow and auditdeny */ + if (node->key.specified & AVTAB_XPERMS_ALLOWED) + xperms->len = 1; +} + +/* + * Compute access vectors and extended permissions based on a context + * structure pair for the permissions in a particular class. */ static void context_struct_compute_av(struct context *scontext, - struct context *tcontext, - u16 tclass, - struct av_decision *avd) + struct context *tcontext, + u16 tclass, + struct av_decision *avd, + struct extended_perms *xperms) { struct constraint_node *constraint; struct role_allow *ra; @@ -633,6 +663,10 @@ static void context_struct_compute_av(struct context *scontext, avd->allowed = 0; avd->auditallow = 0; avd->auditdeny = 0xffffffff; + if (xperms) { + memset(&xperms->drivers, 0, sizeof(xperms->drivers)); + xperms->len = 0; + } if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { if (printk_ratelimit()) @@ -647,7 +681,7 @@ static void context_struct_compute_av(struct context *scontext, * this permission check, then use it. */ avkey.target_class = tclass; - avkey.specified = AVTAB_AV; + avkey.specified = AVTAB_AV | AVTAB_XPERMS; sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1); BUG_ON(!sattr); tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1); @@ -660,15 +694,18 @@ static void context_struct_compute_av(struct context *scontext, node; node = avtab_search_node_next(node, avkey.specified)) { if (node->key.specified == AVTAB_ALLOWED) - avd->allowed |= node->datum.data; + avd->allowed |= node->datum.u.data; else if (node->key.specified == AVTAB_AUDITALLOW) - avd->auditallow |= node->datum.data; + avd->auditallow |= node->datum.u.data; else if (node->key.specified == AVTAB_AUDITDENY) - avd->auditdeny &= node->datum.data; + avd->auditdeny &= node->datum.u.data; + else if (xperms && (node->key.specified & AVTAB_XPERMS)) + services_compute_xperms_drivers(xperms, node); } /* Check conditional av table for additional permissions */ - cond_compute_av(&policydb.te_cond_avtab, &avkey, avd); + cond_compute_av(&policydb.te_cond_avtab, &avkey, + avd, xperms); } } @@ -899,6 +936,139 @@ static void avd_init(struct av_decision *avd) avd->flags = 0; } +void services_compute_xperms_decision(struct extended_perms_decision *xpermd, + struct avtab_node *node) +{ + unsigned int i; + + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { + if (xpermd->driver != node->datum.u.xperms->driver) + return; + } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { + if (!security_xperm_test(node->datum.u.xperms->perms.p, + xpermd->driver)) + return; + } else { + BUG(); + } + + if (node->key.specified == AVTAB_XPERMS_ALLOWED) { + xpermd->used |= XPERMS_ALLOWED; + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { + memset(xpermd->allowed->p, 0xff, + sizeof(xpermd->allowed->p)); + } + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { + for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++) + xpermd->allowed->p[i] |= + node->datum.u.xperms->perms.p[i]; + } + } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) { + xpermd->used |= XPERMS_AUDITALLOW; + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { + memset(xpermd->auditallow->p, 0xff, + sizeof(xpermd->auditallow->p)); + } + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { + for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++) + xpermd->auditallow->p[i] |= + node->datum.u.xperms->perms.p[i]; + } + } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) { + xpermd->used |= XPERMS_DONTAUDIT; + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { + memset(xpermd->dontaudit->p, 0xff, + sizeof(xpermd->dontaudit->p)); + } + if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { + for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++) + xpermd->dontaudit->p[i] |= + node->datum.u.xperms->perms.p[i]; + } + } else { + BUG(); + } +} + +void security_compute_xperms_decision(u32 ssid, + u32 tsid, + u16 orig_tclass, + u8 driver, + struct extended_perms_decision *xpermd) +{ + u16 tclass; + struct context *scontext, *tcontext; + struct avtab_key avkey; + struct avtab_node *node; + struct ebitmap *sattr, *tattr; + struct ebitmap_node *snode, *tnode; + unsigned int i, j; + + xpermd->driver = driver; + xpermd->used = 0; + memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p)); + memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p)); + memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p)); + + read_lock(&policy_rwlock); + if (!ss_initialized) + goto allow; + + scontext = sidtab_search(&sidtab, ssid); + if (!scontext) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, ssid); + goto out; + } + + tcontext = sidtab_search(&sidtab, tsid); + if (!tcontext) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, tsid); + goto out; + } + + tclass = unmap_class(orig_tclass); + if (unlikely(orig_tclass && !tclass)) { + if (policydb.allow_unknown) + goto allow; + goto out; + } + + + if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { + pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass); + goto out; + } + + avkey.target_class = tclass; + avkey.specified = AVTAB_XPERMS; + sattr = flex_array_get(policydb.type_attr_map_array, + scontext->type - 1); + BUG_ON(!sattr); + tattr = flex_array_get(policydb.type_attr_map_array, + tcontext->type - 1); + BUG_ON(!tattr); + ebitmap_for_each_positive_bit(sattr, snode, i) { + ebitmap_for_each_positive_bit(tattr, tnode, j) { + avkey.source_type = i + 1; + avkey.target_type = j + 1; + for (node = avtab_search_node(&policydb.te_avtab, &avkey); + node; + node = avtab_search_node_next(node, avkey.specified)) + services_compute_xperms_decision(xpermd, node); + + cond_compute_xperms(&policydb.te_cond_avtab, + &avkey, xpermd); + } + } +out: + read_unlock(&policy_rwlock); + return; +allow: + memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); + goto out; +} /** * security_compute_av - Compute access vector decisions. @@ -906,6 +1076,7 @@ static void avd_init(struct av_decision *avd) * @tsid: target security identifier * @tclass: target security class * @avd: access vector decisions + * @xperms: extended permissions * * Compute a set of access vector decisions based on the * SID pair (@ssid, @tsid) for the permissions in @tclass. @@ -913,13 +1084,15 @@ static void avd_init(struct av_decision *avd) void security_compute_av(u32 ssid, u32 tsid, u16 orig_tclass, - struct av_decision *avd) + struct av_decision *avd, + struct extended_perms *xperms) { u16 tclass; struct context *scontext = NULL, *tcontext = NULL; read_lock(&policy_rwlock); avd_init(avd); + xperms->len = 0; if (!ss_initialized) goto allow; @@ -947,7 +1120,7 @@ void security_compute_av(u32 ssid, goto allow; goto out; } - context_struct_compute_av(scontext, tcontext, tclass, avd); + context_struct_compute_av(scontext, tcontext, tclass, avd, xperms); map_decision(orig_tclass, avd, policydb.allow_unknown); out: read_unlock(&policy_rwlock); @@ -993,7 +1166,7 @@ void security_compute_av_user(u32 ssid, goto out; } - context_struct_compute_av(scontext, tcontext, tclass, avd); + context_struct_compute_av(scontext, tcontext, tclass, avd, NULL); out: read_unlock(&policy_rwlock); return; @@ -1515,7 +1688,7 @@ static int security_compute_sid(u32 ssid, if (avdatum) { /* Use the type from the type transition/member/change rule. */ - newcontext.type = avdatum->data; + newcontext.type = avdatum->u.data; } /* if we have a objname this is a file trans check so check those rules */ diff --git a/security/selinux/ss/services.h b/security/selinux/ss/services.h index e8d907e903cd..6abcd8729ec3 100644 --- a/security/selinux/ss/services.h +++ b/security/selinux/ss/services.h @@ -11,5 +11,11 @@ extern struct policydb policydb; +void services_compute_xperms_drivers(struct extended_perms *xperms, + struct avtab_node *node); + +void services_compute_xperms_decision(struct extended_perms_decision *xpermd, + struct avtab_node *node); + #endif /* _SS_SERVICES_H_ */ |