diff options
Diffstat (limited to 'security/keys')
-rw-r--r-- | security/keys/Makefile | 1 | ||||
-rw-r--r-- | security/keys/internal.h | 26 | ||||
-rw-r--r-- | security/keys/key.c | 81 | ||||
-rw-r--r-- | security/keys/keyctl.c | 301 | ||||
-rw-r--r-- | security/keys/keyring.c | 86 | ||||
-rw-r--r-- | security/keys/permission.c | 70 | ||||
-rw-r--r-- | security/keys/proc.c | 2 | ||||
-rw-r--r-- | security/keys/process_keys.c | 164 | ||||
-rw-r--r-- | security/keys/request_key.c | 38 | ||||
-rw-r--r-- | security/keys/request_key_auth.c | 5 |
10 files changed, 467 insertions, 307 deletions
diff --git a/security/keys/Makefile b/security/keys/Makefile index c392d750b208..5145adfb6a05 100644 --- a/security/keys/Makefile +++ b/security/keys/Makefile @@ -6,6 +6,7 @@ obj-y := \ key.o \ keyring.o \ keyctl.o \ + permission.o \ process_keys.o \ request_key.o \ request_key_auth.o \ diff --git a/security/keys/internal.h b/security/keys/internal.h index 46c8602661c9..db99ed434f3a 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -71,26 +71,26 @@ extern void keyring_publish_name(struct key *keyring); extern int __key_link(struct key *keyring, struct key *key); -extern struct key *__keyring_search_one(struct key *keyring, - const struct key_type *type, - const char *description, - key_perm_t perm); +extern key_ref_t __keyring_search_one(key_ref_t keyring_ref, + const struct key_type *type, + const char *description, + key_perm_t perm); extern struct key *keyring_search_instkey(struct key *keyring, key_serial_t target_id); typedef int (*key_match_func_t)(const struct key *, const void *); -extern struct key *keyring_search_aux(struct key *keyring, - struct task_struct *tsk, - struct key_type *type, - const void *description, - key_match_func_t match); +extern key_ref_t keyring_search_aux(key_ref_t keyring_ref, + struct task_struct *tsk, + struct key_type *type, + const void *description, + key_match_func_t match); -extern struct key *search_process_keyrings(struct key_type *type, - const void *description, - key_match_func_t match, - struct task_struct *tsk); +extern key_ref_t search_process_keyrings(struct key_type *type, + const void *description, + key_match_func_t match, + struct task_struct *tsk); extern struct key *find_keyring_by_name(const char *name, key_serial_t bound); diff --git a/security/keys/key.c b/security/keys/key.c index fb89f9844465..2182be9e9309 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -693,14 +693,15 @@ void key_type_put(struct key_type *ktype) * - the key has an incremented refcount * - we need to put the key if we get an error */ -static inline struct key *__key_update(struct key *key, const void *payload, - size_t plen) +static inline key_ref_t __key_update(key_ref_t key_ref, + const void *payload, size_t plen) { + struct key *key = key_ref_to_ptr(key_ref); int ret; /* need write permission on the key to update it */ ret = -EACCES; - if (!key_permission(key, KEY_WRITE)) + if (!key_permission(key_ref, KEY_WRITE)) goto error; ret = -EEXIST; @@ -719,12 +720,12 @@ static inline struct key *__key_update(struct key *key, const void *payload, if (ret < 0) goto error; - out: - return key; +out: + return key_ref; - error: +error: key_put(key); - key = ERR_PTR(ret); + key_ref = ERR_PTR(ret); goto out; } /* end __key_update() */ @@ -734,52 +735,56 @@ static inline struct key *__key_update(struct key *key, const void *payload, * search the specified keyring for a key of the same description; if one is * found, update it, otherwise add a new one */ -struct key *key_create_or_update(struct key *keyring, - const char *type, - const char *description, - const void *payload, - size_t plen, - int not_in_quota) +key_ref_t key_create_or_update(key_ref_t keyring_ref, + const char *type, + const char *description, + const void *payload, + size_t plen, + int not_in_quota) { struct key_type *ktype; - struct key *key = NULL; + struct key *keyring, *key = NULL; key_perm_t perm; + key_ref_t key_ref; int ret; - key_check(keyring); - /* look up the key type to see if it's one of the registered kernel * types */ ktype = key_type_lookup(type); if (IS_ERR(ktype)) { - key = ERR_PTR(-ENODEV); + key_ref = ERR_PTR(-ENODEV); goto error; } - ret = -EINVAL; + key_ref = ERR_PTR(-EINVAL); if (!ktype->match || !ktype->instantiate) goto error_2; + keyring = key_ref_to_ptr(keyring_ref); + + key_check(keyring); + + down_write(&keyring->sem); + + /* if we're going to allocate a new key, we're going to have + * to modify the keyring */ + key_ref = ERR_PTR(-EACCES); + if (!key_permission(keyring_ref, KEY_WRITE)) + goto error_3; + /* search for an existing key of the same type and description in the * destination keyring */ - down_write(&keyring->sem); - - key = __keyring_search_one(keyring, ktype, description, 0); - if (!IS_ERR(key)) + key_ref = __keyring_search_one(keyring_ref, ktype, description, 0); + if (!IS_ERR(key_ref)) goto found_matching_key; - /* if we're going to allocate a new key, we're going to have to modify - * the keyring */ - ret = -EACCES; - if (!key_permission(keyring, KEY_WRITE)) - goto error_3; - /* decide on the permissions we want */ - perm = KEY_USR_VIEW | KEY_USR_SEARCH | KEY_USR_LINK; + perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK; + perm |= KEY_USR_VIEW | KEY_USR_SEARCH | KEY_USR_LINK; if (ktype->read) - perm |= KEY_USR_READ; + perm |= KEY_POS_READ | KEY_USR_READ; if (ktype == &key_type_keyring || ktype->update) perm |= KEY_USR_WRITE; @@ -788,7 +793,7 @@ struct key *key_create_or_update(struct key *keyring, key = key_alloc(ktype, description, current->fsuid, current->fsgid, perm, not_in_quota); if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = ERR_PTR(PTR_ERR(key)); goto error_3; } @@ -796,15 +801,18 @@ struct key *key_create_or_update(struct key *keyring, ret = __key_instantiate_and_link(key, payload, plen, keyring, NULL); if (ret < 0) { key_put(key); - key = ERR_PTR(ret); + key_ref = ERR_PTR(ret); + goto error_3; } + key_ref = make_key_ref(key, is_key_possessed(keyring_ref)); + error_3: up_write(&keyring->sem); error_2: key_type_put(ktype); error: - return key; + return key_ref; found_matching_key: /* we found a matching key, so we're going to try to update it @@ -813,7 +821,7 @@ struct key *key_create_or_update(struct key *keyring, up_write(&keyring->sem); key_type_put(ktype); - key = __key_update(key, payload, plen); + key_ref = __key_update(key_ref, payload, plen); goto error; } /* end key_create_or_update() */ @@ -824,15 +832,16 @@ EXPORT_SYMBOL(key_create_or_update); /* * update a key */ -int key_update(struct key *key, const void *payload, size_t plen) +int key_update(key_ref_t key_ref, const void *payload, size_t plen) { + struct key *key = key_ref_to_ptr(key_ref); int ret; key_check(key); /* the key must be writable */ ret = -EACCES; - if (!key_permission(key, KEY_WRITE)) + if (!key_permission(key_ref, KEY_WRITE)) goto error; /* attempt to update it if supported */ diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index a6516a64b297..4c670ee6acf9 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -34,7 +34,7 @@ asmlinkage long sys_add_key(const char __user *_type, size_t plen, key_serial_t ringid) { - struct key *keyring, *key; + key_ref_t keyring_ref, key_ref; char type[32], *description; void *payload; long dlen, ret; @@ -86,25 +86,25 @@ asmlinkage long sys_add_key(const char __user *_type, } /* find the target keyring (which must be writable) */ - keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error3; } /* create or update the requested key and add it to the target * keyring */ - key = key_create_or_update(keyring, type, description, - payload, plen, 0); - if (!IS_ERR(key)) { - ret = key->serial; - key_put(key); + key_ref = key_create_or_update(keyring_ref, type, description, + payload, plen, 0); + if (!IS_ERR(key_ref)) { + ret = key_ref_to_ptr(key_ref)->serial; + key_ref_put(key_ref); } else { - ret = PTR_ERR(key); + ret = PTR_ERR(key_ref); } - key_put(keyring); + key_ref_put(keyring_ref); error3: kfree(payload); error2: @@ -131,7 +131,8 @@ asmlinkage long sys_request_key(const char __user *_type, key_serial_t destringid) { struct key_type *ktype; - struct key *key, *dest; + struct key *key; + key_ref_t dest_ref; char type[32], *description, *callout_info; long dlen, ret; @@ -187,11 +188,11 @@ asmlinkage long sys_request_key(const char __user *_type, } /* get the destination keyring if specified */ - dest = NULL; + dest_ref = NULL; if (destringid) { - dest = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE); - if (IS_ERR(dest)) { - ret = PTR_ERR(dest); + dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE); + if (IS_ERR(dest_ref)) { + ret = PTR_ERR(dest_ref); goto error3; } } @@ -204,7 +205,8 @@ asmlinkage long sys_request_key(const char __user *_type, } /* do the search */ - key = request_key_and_link(ktype, description, callout_info, dest); + key = request_key_and_link(ktype, description, callout_info, + key_ref_to_ptr(dest_ref)); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error5; @@ -216,7 +218,7 @@ asmlinkage long sys_request_key(const char __user *_type, error5: key_type_put(ktype); error4: - key_put(dest); + key_ref_put(dest_ref); error3: kfree(callout_info); error2: @@ -234,17 +236,17 @@ asmlinkage long sys_request_key(const char __user *_type, */ long keyctl_get_keyring_ID(key_serial_t id, int create) { - struct key *key; + key_ref_t key_ref; long ret; - key = lookup_user_key(NULL, id, create, 0, KEY_SEARCH); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, create, 0, KEY_SEARCH); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error; } - ret = key->serial; - key_put(key); + ret = key_ref_to_ptr(key_ref)->serial; + key_ref_put(key_ref); error: return ret; @@ -302,7 +304,7 @@ long keyctl_update_key(key_serial_t id, const void __user *_payload, size_t plen) { - struct key *key; + key_ref_t key_ref; void *payload; long ret; @@ -324,16 +326,16 @@ long keyctl_update_key(key_serial_t id, } /* find the target key (which must be writable) */ - key = lookup_user_key(NULL, id, 0, 0, KEY_WRITE); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error2; } /* update the key */ - ret = key_update(key, payload, plen); + ret = key_update(key_ref, payload, plen); - key_put(key); + key_ref_put(key_ref); error2: kfree(payload); error: @@ -349,19 +351,19 @@ long keyctl_update_key(key_serial_t id, */ long keyctl_revoke_key(key_serial_t id) { - struct key *key; + key_ref_t key_ref; long ret; - key = lookup_user_key(NULL, id, 0, 0, KEY_WRITE); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error; } - key_revoke(key); + key_revoke(key_ref_to_ptr(key_ref)); ret = 0; - key_put(key); + key_ref_put(key_ref); error: return ret; @@ -375,18 +377,18 @@ long keyctl_revoke_key(key_serial_t id) */ long keyctl_keyring_clear(key_serial_t ringid) { - struct key *keyring; + key_ref_t keyring_ref; long ret; - keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error; } - ret = keyring_clear(keyring); + ret = keyring_clear(key_ref_to_ptr(keyring_ref)); - key_put(keyring); + key_ref_put(keyring_ref); error: return ret; @@ -401,26 +403,26 @@ long keyctl_keyring_clear(key_serial_t ringid) */ long keyctl_keyring_link(key_serial_t id, key_serial_t ringid) { - struct key *keyring, *key; + key_ref_t keyring_ref, key_ref; long ret; - keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error; } - key = lookup_user_key(NULL, id, 1, 0, KEY_LINK); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, 1, 0, KEY_LINK); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error2; } - ret = key_link(keyring, key); + ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref)); - key_put(key); + key_ref_put(key_ref); error2: - key_put(keyring); + key_ref_put(keyring_ref); error: return ret; @@ -435,26 +437,26 @@ long keyctl_keyring_link(key_serial_t id, key_serial_t ringid) */ long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid) { - struct key *keyring, *key; + key_ref_t keyring_ref, key_ref; long ret; - keyring = lookup_user_key(NULL, ringid, 0, 0, KEY_WRITE); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_WRITE); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error; } - key = lookup_user_key(NULL, id, 0, 0, 0); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, 0, 0, 0); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error2; } - ret = key_unlink(keyring, key); + ret = key_unlink(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref)); - key_put(key); + key_ref_put(key_ref); error2: - key_put(keyring); + key_ref_put(keyring_ref); error: return ret; @@ -476,24 +478,26 @@ long keyctl_describe_key(key_serial_t keyid, size_t buflen) { struct key *key, *instkey; + key_ref_t key_ref; char *tmpbuf; long ret; - key = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW); - if (IS_ERR(key)) { + key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW); + if (IS_ERR(key_ref)) { /* viewing a key under construction is permitted if we have the * authorisation token handy */ - if (PTR_ERR(key) == -EACCES) { + if (PTR_ERR(key_ref) == -EACCES) { instkey = key_get_instantiation_authkey(keyid); if (!IS_ERR(instkey)) { key_put(instkey); - key = lookup_user_key(NULL, keyid, 0, 1, 0); - if (!IS_ERR(key)) + key_ref = lookup_user_key(NULL, keyid, + 0, 1, 0); + if (!IS_ERR(key_ref)) goto okay; } } - ret = PTR_ERR(key); + ret = PTR_ERR(key_ref); goto error; } @@ -504,13 +508,16 @@ okay: if (!tmpbuf) goto error2; + key = key_ref_to_ptr(key_ref); + ret = snprintf(tmpbuf, PAGE_SIZE - 1, - "%s;%d;%d;%06x;%s", - key->type->name, - key->uid, - key->gid, - key->perm, - key->description ? key->description :"" + "%s;%d;%d;%08x;%s", + key_ref_to_ptr(key_ref)->type->name, + key_ref_to_ptr(key_ref)->uid, + key_ref_to_ptr(key_ref)->gid, + key_ref_to_ptr(key_ref)->perm, + key_ref_to_ptr(key_ref)->description ? + key_ref_to_ptr(key_ref)->description : "" ); /* include a NUL char at the end of the data */ @@ -530,7 +537,7 @@ okay: kfree(tmpbuf); error2: - key_put(key); + key_ref_put(key_ref); error: return ret; @@ -552,7 +559,7 @@ long keyctl_keyring_search(key_serial_t ringid, key_serial_t destringid) { struct key_type *ktype; - struct key *keyring, *key, *dest; + key_ref_t keyring_ref, key_ref, dest_ref; char type[32], *description; long dlen, ret; @@ -581,18 +588,18 @@ long keyctl_keyring_search(key_serial_t ringid, goto error2; /* get the keyring at which to begin the search */ - keyring = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error2; } /* get the destination keyring if specified */ - dest = NULL; + dest_ref = NULL; if (destringid) { - dest = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE); - if (IS_ERR(dest)) { - ret = PTR_ERR(dest); + dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE); + if (IS_ERR(dest_ref)) { + ret = PTR_ERR(dest_ref); goto error3; } } @@ -605,9 +612,9 @@ long keyctl_keyring_search(key_serial_t ringid, } /* do the search */ - key = keyring_search(keyring, ktype, description); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = keyring_search(keyring_ref, ktype, description); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); /* treat lack or presence of a negative key the same */ if (ret == -EAGAIN) @@ -616,26 +623,26 @@ long keyctl_keyring_search(key_serial_t ringid, } /* link the resulting key to the destination keyring if we can */ - if (dest) { + if (dest_ref) { ret = -EACCES; - if (!key_permission(key, KEY_LINK)) + if (!key_permission(key_ref, KEY_LINK)) goto error6; - ret = key_link(dest, key); + ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref)); if (ret < 0) goto error6; } - ret = key->serial; + ret = key_ref_to_ptr(key_ref)->serial; error6: - key_put(key); + key_ref_put(key_ref); error5: key_type_put(ktype); error4: - key_put(dest); + key_ref_put(dest_ref); error3: - key_put(keyring); + key_ref_put(keyring_ref); error2: kfree(description); error: @@ -645,16 +652,6 @@ long keyctl_keyring_search(key_serial_t ringid, /*****************************************************************************/ /* - * see if the key we're looking at is the target key - */ -static int keyctl_read_key_same(const struct key *key, const void *target) -{ - return key == target; - -} /* end keyctl_read_key_same() */ - -/*****************************************************************************/ -/* * read a user key's payload * - the keyring must be readable or the key must be searchable from the * process's keyrings @@ -665,38 +662,33 @@ static int keyctl_read_key_same(const struct key *key, const void *target) */ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) { - struct key *key, *skey; + struct key *key; + key_ref_t key_ref; long ret; /* find the key first */ - key = lookup_user_key(NULL, keyid, 0, 0, 0); - if (!IS_ERR(key)) { - /* see if we can read it directly */ - if (key_permission(key, KEY_READ)) - goto can_read_key; - - /* we can't; see if it's searchable from this process's - * keyrings - * - we automatically take account of the fact that it may be - * dangling off an instantiation key - */ - skey = search_process_keyrings(key->type, key, - keyctl_read_key_same, current); - if (!IS_ERR(skey)) - goto can_read_key2; - - ret = PTR_ERR(skey); - if (ret == -EAGAIN) - ret = -EACCES; - goto error2; + key_ref = lookup_user_key(NULL, keyid, 0, 0, 0); + if (IS_ERR(key_ref)) { + ret = -ENOKEY; + goto error; } - ret = -ENOKEY; - goto error; + key = key_ref_to_ptr(key_ref); + + /* see if we can read it directly */ + if (key_permission(key_ref, KEY_READ)) + goto can_read_key; + + /* we can't; see if it's searchable from this process's keyrings + * - we automatically take account of the fact that it may be + * dangling off an instantiation key + */ + if (!is_key_possessed(key_ref)) { + ret = -EACCES; + goto error2; + } /* the key is probably readable - now try to read it */ - can_read_key2: - key_put(skey); can_read_key: ret = key_validate(key); if (ret == 0) { @@ -727,18 +719,21 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid) { struct key *key; + key_ref_t key_ref; long ret; ret = 0; if (uid == (uid_t) -1 && gid == (gid_t) -1) goto error; - key = lookup_user_key(NULL, id, 1, 1, 0); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, 1, 1, 0); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error; } + key = key_ref_to_ptr(key_ref); + /* make the changes with the locks held to prevent chown/chown races */ ret = -EACCES; down_write(&key->sem); @@ -784,18 +779,21 @@ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid) long keyctl_setperm_key(key_serial_t id, key_perm_t perm) { struct key *key; + key_ref_t key_ref; long ret; ret = -EINVAL; - if (perm & ~(KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL)) + if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL)) goto error; - key = lookup_user_key(NULL, id, 1, 1, 0); - if (IS_ERR(key)) { - ret = PTR_ERR(key); + key_ref = lookup_user_key(NULL, id, 1, 1, 0); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); goto error; } + key = key_ref_to_ptr(key_ref); + /* make the changes with the locks held to prevent chown/chmod races */ ret = -EACCES; down_write(&key->sem); @@ -824,7 +822,8 @@ long keyctl_instantiate_key(key_serial_t id, key_serial_t ringid) { struct request_key_auth *rka; - struct key *instkey, *keyring; + struct key *instkey; + key_ref_t keyring_ref; void *payload; long ret; @@ -857,21 +856,21 @@ long keyctl_instantiate_key(key_serial_t id, /* find the destination keyring amongst those belonging to the * requesting task */ - keyring = NULL; + keyring_ref = NULL; if (ringid) { - keyring = lookup_user_key(rka->context, ringid, 1, 0, - KEY_WRITE); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(rka->context, ringid, 1, 0, + KEY_WRITE); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error3; } } /* instantiate the key and link it into a keyring */ ret = key_instantiate_and_link(rka->target_key, payload, plen, - keyring, instkey); + key_ref_to_ptr(keyring_ref), instkey); - key_put(keyring); + key_ref_put(keyring_ref); error3: key_put(instkey); error2: @@ -889,7 +888,8 @@ long keyctl_instantiate_key(key_serial_t id, long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid) { struct request_key_auth *rka; - struct key *instkey, *keyring; + struct key *instkey; + key_ref_t keyring_ref; long ret; /* find the instantiation authorisation key */ @@ -903,19 +903,20 @@ long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid) /* find the destination keyring if present (which must also be * writable) */ - keyring = NULL; + keyring_ref = NULL; if (ringid) { - keyring = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); - if (IS_ERR(keyring)) { - ret = PTR_ERR(keyring); + keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); + if (IS_ERR(keyring_ref)) { + ret = PTR_ERR(keyring_ref); goto error2; } } /* instantiate the key and link it into a keyring */ - ret = key_negate_and_link(rka->target_key, timeout, keyring, instkey); + ret = key_negate_and_link(rka->target_key, timeout, + key_ref_to_ptr(keyring_ref), instkey); - key_put(keyring); + key_ref_put(keyring_ref); error2: key_put(instkey); error: diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 9c208c756df8..0639396dd441 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -309,7 +309,7 @@ struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid, int ret; keyring = key_alloc(&key_type_keyring, description, - uid, gid, KEY_USR_ALL, not_in_quota); + uid, gid, KEY_POS_ALL | KEY_USR_ALL, not_in_quota); if (!IS_ERR(keyring)) { ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL); @@ -333,12 +333,13 @@ struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid, * - we rely on RCU to prevent the keyring lists from disappearing on us * - we return -EAGAIN if we didn't find any matching key * - we return -ENOKEY if we only found negative matching keys + * - we propagate the possession attribute from the keyring ref to the key ref */ -struct key *keyring_search_aux(struct key *keyring, - struct task_struct *context, - struct key_type *type, - const void *description, - key_match_func_t match) +key_ref_t keyring_search_aux(key_ref_t keyring_ref, + struct task_struct *context, + struct key_type *type, + const void *description, + key_match_func_t match) { struct { struct keyring_list *keylist; @@ -347,29 +348,33 @@ struct key *keyring_search_aux(struct key *keyring, struct keyring_list *keylist; struct timespec now; - struct key *key; + unsigned long possessed; + struct key *keyring, *key; + key_ref_t key_ref; long err; int sp, kix; + keyring = key_ref_to_ptr(keyring_ref); + possessed = is_key_possessed(keyring_ref); key_check(keyring); - rcu_read_lock(); - /* top keyring must have search permission to begin the search */ - key = ERR_PTR(-EACCES); - if (!key_task_permission(keyring, context, KEY_SEARCH)) + key_ref = ERR_PTR(-EACCES); + if (!key_task_permission(keyring_ref, context, KEY_SEARCH)) goto error; - key = ERR_PTR(-ENOTDIR); + key_ref = ERR_PTR(-ENOTDIR); if (keyring->type != &key_type_keyring) goto error; + rcu_read_lock(); + now = current_kernel_time(); err = -EAGAIN; sp = 0; /* start processing a new keyring */ - descend: +descend: if (test_bit(KEY_FLAG_REVOKED, &keyring->flags)) goto not_this_keyring; @@ -397,7 +402,8 @@ struct key *keyring_search_aux(struct key *keyring, continue; /* key must have search permissions */ - if (!key_task_permission(key, context, KEY_SEARCH)) + if (!key_task_permission(make_key_ref(key, possessed), + context, KEY_SEARCH)) continue; /* we set a different error code if we find a negative key */ @@ -411,7 +417,7 @@ struct key *keyring_search_aux(struct key *keyring, /* search through the keyrings nested in this one */ kix = 0; - ascend: +ascend: for (; kix < keylist->nkeys; kix++) { key = keylist->keys[kix]; if (key->type != &key_type_keyring) @@ -423,7 +429,8 @@ struct key *keyring_search_aux(struct key *keyring, if (sp >= KEYRING_SEARCH_MAX_DEPTH) continue; - if (!key_task_permission(key, context, KEY_SEARCH)) + if (!key_task_permission(make_key_ref(key, possessed), + context, KEY_SEARCH)) continue; /* stack the current position */ @@ -438,7 +445,7 @@ struct key *keyring_search_aux(struct key *keyring, /* the keyring we're looking at was disqualified or didn't contain a * matching key */ - not_this_keyring: +not_this_keyring: if (sp > 0) { /* resume the processing of a keyring higher up in the tree */ sp--; @@ -447,16 +454,18 @@ struct key *keyring_search_aux(struct key *keyring, goto ascend; } - key = ERR_PTR(err); - goto error; + key_ref = ERR_PTR(err); + goto error_2; /* we found a viable match */ - found: +found: atomic_inc(&key->usage); key_check(key); - error: + key_ref = make_key_ref(key, possessed); +error_2: rcu_read_unlock(); - return key; +error: + return key_ref; } /* end keyring_search_aux() */ @@ -469,9 +478,9 @@ struct key *keyring_search_aux(struct key *keyring, * - we return -EAGAIN if we didn't find any matching key * - we return -ENOKEY if we only found negative matching keys */ -struct key *keyring_search(struct key *keyring, - struct key_type *type, - const char *description) +key_ref_t keyring_search(key_ref_t keyring, + struct key_type *type, + const char *description) { if (!type->match) return ERR_PTR(-ENOKEY); @@ -488,15 +497,19 @@ EXPORT_SYMBOL(keyring_search); * search the given keyring only (no recursion) * - keyring must be locked by caller */ -struct key *__keyring_search_one(struct key *keyring, - const struct key_type *ktype, - const char *description, - key_perm_t perm) +key_ref_t __keyring_search_one(key_ref_t keyring_ref, + const struct key_type *ktype, + const char *description, + key_perm_t perm) { struct keyring_list *klist; - struct key *key; + unsigned long possessed; + struct key *keyring, *key; int loop; + keyring = key_ref_to_ptr(keyring_ref); + possessed = is_key_possessed(keyring_ref); + rcu_read_lock(); klist = rcu_dereference(keyring->payload.subscriptions); @@ -507,21 +520,21 @@ struct key *__keyring_search_one(struct key *keyring, if (key->type == ktype && (!key->type->match || key->type->match(key, description)) && - key_permission(key, perm) && + key_permission(make_key_ref(key, possessed), + perm) && !test_bit(KEY_FLAG_REVOKED, &key->flags) ) goto found; } } - key = ERR_PTR(-ENOKEY); - goto error; + rcu_read_unlock(); + return ERR_PTR(-ENOKEY); found: atomic_inc(&key->usage); - error: rcu_read_unlock(); - return key; + return make_key_ref(key, possessed); } /* end __keyring_search_one() */ @@ -603,7 +616,8 @@ struct key *find_keyring_by_name(const char *name, key_serial_t bound) if (strcmp(keyring->description, name) != 0) continue; - if (!key_permission(keyring, KEY_SEARCH)) + if (!key_permission(make_key_ref(keyring, 0), + KEY_SEARCH)) continue; /* found a potential candidate, but we still need to diff --git a/security/keys/permission.c b/security/keys/permission.c new file mode 100644 index 000000000000..03db073ba45c --- /dev/null +++ b/security/keys/permission.c @@ -0,0 +1,70 @@ +/* permission.c: key permission determination + * + * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/module.h> +#include "internal.h" + +/*****************************************************************************/ +/* + * check to see whether permission is granted to use a key in the desired way, + * but permit the security modules to override + */ +int key_task_permission(const key_ref_t key_ref, + struct task_struct *context, + key_perm_t perm) +{ + struct key *key; + key_perm_t kperm; + int ret; + + key = key_ref_to_ptr(key_ref); + + /* use the second 8-bits of permissions for keys the caller owns */ + if (key->uid == context->fsuid) { + kperm = key->perm >> 16; + goto use_these_perms; + } + + /* use the third 8-bits of permissions for keys the caller has a group + * membership in common with */ + if (key->gid != -1 && key->perm & KEY_GRP_ALL) { + if (key->gid == context->fsgid) { + kperm = key->perm >> 8; + goto use_these_perms; + } + + task_lock(context); + ret = groups_search(context->group_info, key->gid); + task_unlock(context); + + if (ret) { + kperm = key->perm >> 8; + goto use_these_perms; + } + } + + /* otherwise use the least-significant 8-bits */ + kperm = key->perm; + +use_these_perms: + /* use the top 8-bits of permissions for keys the caller possesses + * - possessor permissions are additive with other permissions + */ + if (is_key_possessed(key_ref)) + kperm |= key->perm >> 24; + + kperm = kperm & perm & KEY_ALL; + + return kperm == perm; + +} /* end key_task_permission() */ + +EXPORT_SYMBOL(key_task_permission); diff --git a/security/keys/proc.c b/security/keys/proc.c index c55cf1fd0826..12b750e51fbf 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -167,7 +167,7 @@ static int proc_keys_show(struct seq_file *m, void *v) #define showflag(KEY, LETTER, FLAG) \ (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-') - seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %06x %5d %5d %-9.9s ", + seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ", key->serial, showflag(key, 'I', KEY_FLAG_INSTANTIATED), showflag(key, 'R', KEY_FLAG_REVOKED), diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index c089f78fb94e..d42d2158ce13 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -39,7 +39,7 @@ struct key root_user_keyring = { .type = &key_type_keyring, .user = &root_key_user, .sem = __RWSEM_INITIALIZER(root_user_keyring.sem), - .perm = KEY_USR_ALL, + .perm = KEY_POS_ALL | KEY_USR_ALL, .flags = 1 << KEY_FLAG_INSTANTIATED, .description = "_uid.0", #ifdef KEY_DEBUGGING @@ -54,7 +54,7 @@ struct key root_session_keyring = { .type = &key_type_keyring, .user = &root_key_user, .sem = __RWSEM_INITIALIZER(root_session_keyring.sem), - .perm = KEY_USR_ALL, + .perm = KEY_POS_ALL | KEY_USR_ALL, .flags = 1 << KEY_FLAG_INSTANTIATED, .description = "_uid_ses.0", #ifdef KEY_DEBUGGING @@ -98,7 +98,7 @@ int alloc_uid_keyring(struct user_struct *user) user->session_keyring = session_keyring; ret = 0; - error: +error: return ret; } /* end alloc_uid_keyring() */ @@ -156,7 +156,7 @@ int install_thread_keyring(struct task_struct *tsk) ret = 0; key_put(old); - error: +error: return ret; } /* end install_thread_keyring() */ @@ -193,7 +193,7 @@ int install_process_keyring(struct task_struct *tsk) } ret = 0; - error: +error: return ret; } /* end install_process_keyring() */ @@ -236,7 +236,7 @@ static int install_session_keyring(struct task_struct *tsk, /* we're using RCU on the pointer */ synchronize_rcu(); key_put(old); - error: +error: return ret; } /* end install_session_keyring() */ @@ -376,13 +376,13 @@ void key_fsgid_changed(struct task_struct *tsk) * - we return -EAGAIN if we didn't find any matching key * - we return -ENOKEY if we found only negative matching keys */ -struct key *search_process_keyrings(struct key_type *type, - const void *description, - key_match_func_t match, - struct task_struct *context) +key_ref_t search_process_keyrings(struct key_type *type, + const void *description, + key_match_func_t match, + struct task_struct *context) { struct request_key_auth *rka; - struct key *key, *ret, *err, *instkey; + key_ref_t key_ref, ret, err, instkey_ref; /* we want to return -EAGAIN or -ENOKEY if any of the keyrings were * searchable, but we failed to find a key or we found a negative key; @@ -391,46 +391,48 @@ struct key *search_process_keyrings(struct key_type *type, * * in terms of priority: success > -ENOKEY > -EAGAIN > other error */ - key = NULL; + key_ref = NULL; ret = NULL; err = ERR_PTR(-EAGAIN); /* search the thread keyring first */ if (context->thread_keyring) { - key = keyring_search_aux(context->thread_keyring, - context, type, description, match); - if (!IS_ERR(key)) + key_ref = keyring_search_aux( + make_key_ref(context->thread_keyring, 1), + context, type, description, match); + if (!IS_ERR(key_ref)) goto found; - switch (PTR_ERR(key)) { + switch (PTR_ERR(key_ref)) { case -EAGAIN: /* no key */ if (ret) break; case -ENOKEY: /* negative key */ - ret = key; + ret = key_ref; break; default: - err = key; + err = key_ref; break; } } /* search the process keyring second */ if (context->signal->process_keyring) { - key = keyring_search_aux(context->signal->process_keyring, - context, type, description, match); - if (!IS_ERR(key)) + key_ref = keyring_search_aux( + make_key_ref(context->signal->process_keyring, 1), + context, type, description, match); + if (!IS_ERR(key_ref)) goto found; - switch (PTR_ERR(key)) { + switch (PTR_ERR(key_ref)) { case -EAGAIN: /* no key */ if (ret) break; case -ENOKEY: /* negative key */ - ret = key; + ret = key_ref; break; default: - err = key; + err = key_ref; break; } } @@ -438,23 +440,25 @@ struct key *search_process_keyrings(struct key_type *type, /* search the session keyring */ if (context->signal->session_keyring) { rcu_read_lock(); - key = keyring_search_aux( - rcu_dereference(context->signal->session_keyring), + key_ref = keyring_search_aux( + make_key_ref(rcu_dereference( + context->signal->session_keyring), + 1), context, type, description, match); rcu_read_unlock(); - if (!IS_ERR(key)) + if (!IS_ERR(key_ref)) goto found; - switch (PTR_ERR(key)) { + switch (PTR_ERR(key_ref)) { case -EAGAIN: /* no key */ if (ret) break; case -ENOKEY: /* negative key */ - ret = key; + ret = key_ref; break; default: - err = key; + err = key_ref; break; } @@ -465,51 +469,54 @@ struct key *search_process_keyrings(struct key_type *type, goto no_key; rcu_read_lock(); - instkey = __keyring_search_one( - rcu_dereference(context->signal->session_keyring), + instkey_ref = __keyring_search_one( + make_key_ref(rcu_dereference( + context->signal->session_keyring), + 1), &key_type_request_key_auth, NULL, 0); rcu_read_unlock(); - if (IS_ERR(instkey)) + if (IS_ERR(instkey_ref)) goto no_key; - rka = instkey->payload.data; + rka = key_ref_to_ptr(instkey_ref)->payload.data; - key = search_process_keyrings(type, description, match, - rka->context); - key_put(instkey); + key_ref = search_process_keyrings(type, description, match, + rka->context); + key_ref_put(instkey_ref); - if (!IS_ERR(key)) + if (!IS_ERR(key_ref)) goto found; - switch (PTR_ERR(key)) { + switch (PTR_ERR(key_ref)) { case -EAGAIN: /* no key */ if (ret) break; case -ENOKEY: /* negative key */ - ret = key; + ret = key_ref; break; default: - err = key; + err = key_ref; break; } } /* or search the user-session keyring */ else { - key = keyring_search_aux(context->user->session_keyring, - context, type, description, match); - if (!IS_ERR(key)) + key_ref = keyring_search_aux( + make_key_ref(context->user->session_keyring, 1), + context, type, description, match); + if (!IS_ERR(key_ref)) goto found; - switch (PTR_ERR(key)) { + switch (PTR_ERR(key_ref)) { case -EAGAIN: /* no key */ if (ret) break; case -ENOKEY: /* negative key */ - ret = key; + ret = key_ref; break; default: - err = key; + err = key_ref; break; } } @@ -517,29 +524,40 @@ struct key *search_process_keyrings(struct key_type *type, no_key: /* no key - decide on the error we're going to go for */ - key = ret ? ret : err; + key_ref = ret ? ret : err; found: - return key; + return key_ref; } /* end search_process_keyrings() */ /*****************************************************************************/ /* + * see if the key we're looking at is the target key + */ +static int lookup_user_key_possessed(const struct key *key, const void *target) +{ + return key == target; + +} /* end lookup_user_key_possessed() */ + +/*****************************************************************************/ +/* * lookup a key given a key ID from userspace with a given permissions mask * - don't create special keyrings unless so requested * - partially constructed keys aren't found unless requested */ -struct key *lookup_user_key(struct task_struct *context, key_serial_t id, - int create, int partial, key_perm_t perm) +key_ref_t lookup_user_key(struct task_struct *context, key_serial_t id, + int create, int partial, key_perm_t perm) { + key_ref_t key_ref, skey_ref; struct key *key; int ret; if (!context) context = current; - key = ERR_PTR(-ENOKEY); + key_ref = ERR_PTR(-ENOKEY); switch (id) { case KEY_SPEC_THREAD_KEYRING: @@ -556,6 +574,7 @@ struct key *lookup_user_key(struct task_struct *context, key_serial_t id, key = context->thread_keyring; atomic_inc(&key->usage); + key_ref = make_key_ref(key, 1); break; case KEY_SPEC_PROCESS_KEYRING: @@ -572,6 +591,7 @@ struct key *lookup_user_key(struct task_struct *context, key_serial_t id, key = context->signal->process_keyring; atomic_inc(&key->usage); + key_ref = make_key_ref(key, 1); break; case KEY_SPEC_SESSION_KEYRING: @@ -579,7 +599,7 @@ struct key *lookup_user_key(struct task_struct *context, key_serial_t id, /* always install a session keyring upon access if one * doesn't exist yet */ ret = install_session_keyring( - context, context->user->session_keyring); + context, context->user->session_keyring); if (ret < 0) goto error; } @@ -588,16 +608,19 @@ struct key *lookup_user_key(struct task_struct *context, key_serial_t id, key = rcu_dereference(context->signal->session_keyring); atomic_inc(&key->usage); rcu_read_unlock(); + key_ref = make_key_ref(key, 1); break; case KEY_SPEC_USER_KEYRING: key = context->user->uid_keyring; atomic_inc(&key->usage); + key_ref = make_key_ref(key, 1); break; case KEY_SPEC_USER_SESSION_KEYRING: key = context->user->session_keyring; atomic_inc(&key->usage); + key_ref = make_key_ref(key, 1); break; case KEY_SPEC_GROUP_KEYRING: @@ -606,13 +629,28 @@ struct key *lookup_user_key(struct task_struct *context, key_serial_t id, goto error; default: - key = ERR_PTR(-EINVAL); + key_ref = ERR_PTR(-EINVAL); if (id < 1) goto error; key = key_lookup(id); - if (IS_ERR(key)) + if (IS_ERR(key)) { + key_ref = ERR_PTR(PTR_ERR(key)); goto error; + } + + key_ref = make_key_ref(key, 0); + + /* check to see if we possess the key */ + skey_ref = search_process_keyrings(key->type, key, + lookup_user_key_possessed, + current); + + if (!IS_ERR(skey_ref)) { + key_put(key); + key_ref = skey_ref; + } + break; } @@ -630,15 +668,15 @@ struct key *lookup_user_key(struct task_struct *context, key_serial_t id, /* check the permissions */ ret = -EACCES; - if (!key_task_permission(key, context, perm)) + if (!key_task_permission(key_ref, context, perm)) goto invalid_key; - error: - return key; +error: + return key_ref; - invalid_key: - key_put(key); - key = ERR_PTR(ret); +invalid_key: + key_ref_put(key_ref); + key_ref = ERR_PTR(ret); goto error; } /* end lookup_user_key() */ @@ -694,9 +732,9 @@ long join_session_keyring(const char *name) ret = keyring->serial; key_put(keyring); - error2: +error2: up(&key_session_sem); - error: +error: return ret; } /* end join_session_keyring() */ diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 90c1506d007c..5cc4bba70db6 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -7,6 +7,8 @@ * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. + * + * See Documentation/keys-request-key.txt */ #include <linux/module.h> @@ -129,7 +131,7 @@ static struct key *__request_key_construction(struct key_type *type, /* create a key and add it to the queue */ key = key_alloc(type, description, - current->fsuid, current->fsgid, KEY_USR_ALL, 0); + current->fsuid, current->fsgid, KEY_POS_ALL, 0); if (IS_ERR(key)) goto alloc_failed; @@ -365,14 +367,24 @@ struct key *request_key_and_link(struct key_type *type, { struct key_user *user; struct key *key; + key_ref_t key_ref; kenter("%s,%s,%s,%p", type->name, description, callout_info, dest_keyring); /* search all the process keyrings for a key */ - key = search_process_keyrings(type, description, type->match, current); + key_ref = search_process_keyrings(type, description, type->match, + current); + + kdebug("search 1: %p", key_ref); - if (PTR_ERR(key) == -EAGAIN) { + if (!IS_ERR(key_ref)) { + key = key_ref_to_ptr(key_ref); + } + else if (PTR_ERR(key_ref) != -EAGAIN) { + key = ERR_PTR(PTR_ERR(key_ref)); + } + else { /* the search failed, but the keyrings were searchable, so we * should consult userspace if we can */ key = ERR_PTR(-ENOKEY); @@ -384,7 +396,7 @@ struct key *request_key_and_link(struct key_type *type, if (!user) goto nomem; - do { + for (;;) { if (signal_pending(current)) goto interrupted; @@ -397,10 +409,22 @@ struct key *request_key_and_link(struct key_type *type, /* someone else made the key we want, so we need to * search again as it might now be available to us */ - key = search_process_keyrings(type, description, - type->match, current); + key_ref = search_process_keyrings(type, description, + type->match, + current); + + kdebug("search 2: %p", key_ref); - } while (PTR_ERR(key) == -EAGAIN); + if (!IS_ERR(key_ref)) { + key = key_ref_to_ptr(key_ref); + break; + } + + if (PTR_ERR(key_ref) != -EAGAIN) { + key = ERR_PTR(PTR_ERR(key_ref)); + break; + } + } key_user_put(user); diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index f22264632229..a8e4069d48cb 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -7,6 +7,8 @@ * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. + * + * See Documentation/keys-request-key.txt */ #include <linux/module.h> @@ -96,6 +98,7 @@ static void request_key_auth_destroy(struct key *key) kenter("{%d}", key->serial); key_put(rka->target_key); + kfree(rka); } /* end request_key_auth_destroy() */ @@ -126,7 +129,7 @@ struct key *request_key_auth_new(struct key *target, struct key **_rkakey) rkakey = key_alloc(&key_type_request_key_auth, desc, current->fsuid, current->fsgid, - KEY_USR_VIEW, 1); + KEY_POS_VIEW | KEY_USR_VIEW, 1); if (IS_ERR(rkakey)) { key_put(keyring); kleave("= %ld", PTR_ERR(rkakey)); |