KEYS: Move the flags representing required permission to linux/key.h

Move the flags representing required permission to linux/key.h as the perm
parameter of security_key_permission() is in terms of them - and not the
permissions mask flags used in key->perm.

Whilst we're at it:

 (1) Rename them to be KEY_NEED_xxx rather than KEY_xxx to avoid collisions
     with symbols in uapi/linux/input.h.

 (2) Don't use key_perm_t for a mask of required permissions, but rather limit
     it to the permissions mask attached to the key and arguments related
     directly to that.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dmitry Kasatkin <d.kasatkin@samsung.com>

11 files changed, 39 insertions, 48 deletions

diff --git a/security/capability.c b/security/capability.c
index 8b4f24ae4338..c1426b91f4bd 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -878,7 +878,7 @@ static void cap_key_free(struct key *key)
 }
 
 static int cap_key_permission(key_ref_t key_ref, const struct cred *cred,
-                              key_perm_t perm)
+                              unsigned perm)
 {
         return 0;
 }
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 80b2aac4f50c..5f20da01fd8d 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -176,20 +176,11 @@ extern int key_task_permission(const key_ref_t key_ref,
 /*
  * Check to see whether permission is granted to use a key in the desired way.
  */
-static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
+static inline int key_permission(const key_ref_t key_ref, unsigned perm)
 {
         return key_task_permission(key_ref, current_cred(), perm);
 }
 
-/* required permissions */
-#define KEY_VIEW        0x01    /* require permission to view attributes */
-#define KEY_READ        0x02    /* require permission to read content */
-#define KEY_WRITE       0x04    /* require permission to update / modify */
-#define KEY_SEARCH      0x08    /* require permission to search (keyring) or find (key) */
-#define KEY_LINK        0x10    /* require permission to link */
-#define KEY_SETATTR     0x20    /* require permission to change attributes */
-#define KEY_ALL         0x3f    /* all the above permissions */
-
 /*
  * Authorisation record for request_key().
  */
diff --git a/security/keys/key.c b/security/keys/key.c
index 6e21c11e48bc..2048a110e7f1 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -714,7 +714,7 @@ static inline key_ref_t __key_update(key_ref_t key_ref,
         int ret;
 
         /* need write permission on the key to update it */
-        ret = key_permission(key_ref, KEY_WRITE);
+        ret = key_permission(key_ref, KEY_NEED_WRITE);
         if (ret < 0)
                 goto error;
 
@@ -838,7 +838,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 
         /* if we're going to allocate a new key, we're going to have
          * to modify the keyring */
-        ret = key_permission(keyring_ref, KEY_WRITE);
+        ret = key_permission(keyring_ref, KEY_NEED_WRITE);
         if (ret < 0) {
                 key_ref = ERR_PTR(ret);
                 goto error_link_end;
@@ -928,7 +928,7 @@ int key_update(key_ref_t key_ref, const void *payload, size_t plen)
         key_check(key);
 
         /* the key must be writable */
-        ret = key_permission(key_ref, KEY_WRITE);
+        ret = key_permission(key_ref, KEY_NEED_WRITE);
         if (ret < 0)
                 goto error;
 
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index cee72ce64222..cd5bd0cef25d 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -111,7 +111,7 @@ SYSCALL_DEFINE5(add_key, const char __user *, _type,
         }
 
         /* find the target keyring (which must be writable) */
-        keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+        keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
         if (IS_ERR(keyring_ref)) {
                 ret = PTR_ERR(keyring_ref);
                 goto error3;
@@ -195,7 +195,7 @@ SYSCALL_DEFINE4(request_key, const char __user *, _type,
         dest_ref = NULL;
         if (destringid) {
                 dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
-                                           KEY_WRITE);
+                                           KEY_NEED_WRITE);
                 if (IS_ERR(dest_ref)) {
                         ret = PTR_ERR(dest_ref);
                         goto error3;
@@ -253,7 +253,7 @@ long keyctl_get_keyring_ID(key_serial_t id, int create)
         long ret;
 
         lflags = create ? KEY_LOOKUP_CREATE : 0;
-        key_ref = lookup_user_key(id, lflags, KEY_SEARCH);
+        key_ref = lookup_user_key(id, lflags, KEY_NEED_SEARCH);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 goto error;
@@ -334,7 +334,7 @@ long keyctl_update_key(key_serial_t id,
         }
 
         /* find the target key (which must be writable) */
-        key_ref = lookup_user_key(id, 0, KEY_WRITE);
+        key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 goto error2;
@@ -365,12 +365,12 @@ long keyctl_revoke_key(key_serial_t id)
         key_ref_t key_ref;
         long ret;
 
-        key_ref = lookup_user_key(id, 0, KEY_WRITE);
+        key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 if (ret != -EACCES)
                         goto error;
-                key_ref = lookup_user_key(id, 0, KEY_SETATTR);
+                key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR);
                 if (IS_ERR(key_ref)) {
                         ret = PTR_ERR(key_ref);
                         goto error;
@@ -401,7 +401,7 @@ long keyctl_invalidate_key(key_serial_t id)
 
         kenter("%d", id);
 
-        key_ref = lookup_user_key(id, 0, KEY_SEARCH);
+        key_ref = lookup_user_key(id, 0, KEY_NEED_SEARCH);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 goto error;
@@ -428,7 +428,7 @@ long keyctl_keyring_clear(key_serial_t ringid)
         key_ref_t keyring_ref;
         long ret;
 
-        keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+        keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
         if (IS_ERR(keyring_ref)) {
                 ret = PTR_ERR(keyring_ref);
 
@@ -470,13 +470,13 @@ long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
         key_ref_t keyring_ref, key_ref;
         long ret;
 
-        keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+        keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
         if (IS_ERR(keyring_ref)) {
                 ret = PTR_ERR(keyring_ref);
                 goto error;
         }
 
-        key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_LINK);
+        key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_NEED_LINK);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 goto error2;
@@ -505,7 +505,7 @@ long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
         key_ref_t keyring_ref, key_ref;
         long ret;
 
-        keyring_ref = lookup_user_key(ringid, 0, KEY_WRITE);
+        keyring_ref = lookup_user_key(ringid, 0, KEY_NEED_WRITE);
         if (IS_ERR(keyring_ref)) {
                 ret = PTR_ERR(keyring_ref);
                 goto error;
@@ -548,7 +548,7 @@ long keyctl_describe_key(key_serial_t keyid,
         char *tmpbuf;
         long ret;
 
-        key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_VIEW);
+        key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_VIEW);
         if (IS_ERR(key_ref)) {
                 /* viewing a key under construction is permitted if we have the
                  * authorisation token handy */
@@ -639,7 +639,7 @@ long keyctl_keyring_search(key_serial_t ringid,
         }
 
         /* get the keyring at which to begin the search */
-        keyring_ref = lookup_user_key(ringid, 0, KEY_SEARCH);
+        keyring_ref = lookup_user_key(ringid, 0, KEY_NEED_SEARCH);
         if (IS_ERR(keyring_ref)) {
                 ret = PTR_ERR(keyring_ref);
                 goto error2;
@@ -649,7 +649,7 @@ long keyctl_keyring_search(key_serial_t ringid,
         dest_ref = NULL;
         if (destringid) {
                 dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
-                                           KEY_WRITE);
+                                           KEY_NEED_WRITE);
                 if (IS_ERR(dest_ref)) {
                         ret = PTR_ERR(dest_ref);
                         goto error3;
@@ -676,7 +676,7 @@ long keyctl_keyring_search(key_serial_t ringid,
 
         /* link the resulting key to the destination keyring if we can */
         if (dest_ref) {
-                ret = key_permission(key_ref, KEY_LINK);
+                ret = key_permission(key_ref, KEY_NEED_LINK);
                 if (ret < 0)
                         goto error6;
 
@@ -727,7 +727,7 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
         key = key_ref_to_ptr(key_ref);
 
         /* see if we can read it directly */
-        ret = key_permission(key_ref, KEY_READ);
+        ret = key_permission(key_ref, KEY_NEED_READ);
         if (ret == 0)
                 goto can_read_key;
         if (ret != -EACCES)
@@ -799,7 +799,7 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group)
                 goto error;
 
         key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
-                                  KEY_SETATTR);
+                                  KEY_NEED_SETATTR);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 goto error;
@@ -905,7 +905,7 @@ long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
                 goto error;
 
         key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
-                                  KEY_SETATTR);
+                                  KEY_NEED_SETATTR);
         if (IS_ERR(key_ref)) {
                 ret = PTR_ERR(key_ref);
                 goto error;
@@ -947,7 +947,7 @@ static long get_instantiation_keyring(key_serial_t ringid,
 
         /* if a specific keyring is nominated by ID, then use that */
         if (ringid > 0) {
-                dkref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+                dkref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
                 if (IS_ERR(dkref))
                         return PTR_ERR(dkref);
                 *_dest_keyring = key_ref_to_ptr(dkref);
@@ -1315,7 +1315,7 @@ long keyctl_set_timeout(key_serial_t id, unsigned timeout)
         long ret;
 
         key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
-                                  KEY_SETATTR);
+                                  KEY_NEED_SETATTR);
         if (IS_ERR(key_ref)) {
                 /* setting the timeout on a key under construction is permitted
                  * if we have the authorisation token handy */
@@ -1418,7 +1418,7 @@ long keyctl_get_security(key_serial_t keyid,
         char *context;
         long ret;
 
-        key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_VIEW);
+        key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_VIEW);
         if (IS_ERR(key_ref)) {
                 if (PTR_ERR(key_ref) != -EACCES)
                         return PTR_ERR(key_ref);
@@ -1482,7 +1482,7 @@ long keyctl_session_to_parent(void)
         struct cred *cred;
         int ret;
 
-        keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_LINK);
+        keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_NEED_LINK);
         if (IS_ERR(keyring_r))
                 return PTR_ERR(keyring_r);
 
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 2fb2576dc644..9cf2575f0d97 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -541,7 +541,7 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
         /* key must have search permissions */
         if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM) &&
             key_task_permission(make_key_ref(key, ctx->possessed),
-                                ctx->cred, KEY_SEARCH) < 0) {
+                                ctx->cred, KEY_NEED_SEARCH) < 0) {
                 ctx->result = ERR_PTR(-EACCES);
                 kleave(" = %d [!perm]", ctx->skipped_ret);
                 goto skipped;
@@ -721,7 +721,7 @@ ascend_to_node:
                 /* Search a nested keyring */
                 if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM) &&
                     key_task_permission(make_key_ref(key, ctx->possessed),
-                                        ctx->cred, KEY_SEARCH) < 0)
+                                        ctx->cred, KEY_NEED_SEARCH) < 0)
                         continue;
 
                 /* stack the current position */
@@ -843,7 +843,7 @@ key_ref_t keyring_search_aux(key_ref_t keyring_ref,
                 return ERR_PTR(-ENOTDIR);
 
         if (!(ctx->flags & KEYRING_SEARCH_NO_CHECK_PERM)) {
-                err = key_task_permission(keyring_ref, ctx->cred, KEY_SEARCH);
+                err = key_task_permission(keyring_ref, ctx->cred, KEY_NEED_SEARCH);
                 if (err < 0)
                         return ERR_PTR(err);
         }
@@ -973,7 +973,7 @@ struct key *find_keyring_by_name(const char *name, bool skip_perm_check)
 
                         if (!skip_perm_check &&
                             key_permission(make_key_ref(keyring, 0),
-                                           KEY_SEARCH) < 0)
+                                           KEY_NEED_SEARCH) < 0)
                                 continue;
 
                         /* we've got a match but we might end up racing with
diff --git a/security/keys/permission.c b/security/keys/permission.c
index efcc0c855a0d..732cc0beffdf 100644
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -28,7 +28,7 @@
  * permissions bits or the LSM check.
  */
 int key_task_permission(const key_ref_t key_ref, const struct cred *cred,
-                        key_perm_t perm)
+                        unsigned perm)
 {
         struct key *key;
         key_perm_t kperm;
@@ -68,7 +68,7 @@ use_these_perms:
         if (is_key_possessed(key_ref))
                 kperm |= key->perm >> 24;
 
-        kperm = kperm & perm & KEY_ALL;
+        kperm = kperm & perm & KEY_NEED_ALL;
 
         if (kperm != perm)
                 return -EACCES;
diff --git a/security/keys/persistent.c b/security/keys/persistent.c
index 0ad3ee283781..c9fae5ea89fe 100644
--- a/security/keys/persistent.c
+++ b/security/keys/persistent.c
@@ -108,7 +108,7 @@ static long key_get_persistent(struct user_namespace *ns, kuid_t uid,
         return PTR_ERR(persistent_ref);
 
 found:
-        ret = key_task_permission(persistent_ref, current_cred(), KEY_LINK);
+        ret = key_task_permission(persistent_ref, current_cred(), KEY_NEED_LINK);
         if (ret == 0) {
                 persistent = key_ref_to_ptr(persistent_ref);
                 ret = key_link(key_ref_to_ptr(dest_ref), persistent);
@@ -151,7 +151,7 @@ long keyctl_get_persistent(uid_t _uid, key_serial_t destid)
         }
 
         /* There must be a destination keyring */
-        dest_ref = lookup_user_key(destid, KEY_LOOKUP_CREATE, KEY_WRITE);
+        dest_ref = lookup_user_key(destid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE);
         if (IS_ERR(dest_ref))
                 return PTR_ERR(dest_ref);
         if (key_ref_to_ptr(dest_ref)->type != &key_type_keyring) {
diff --git a/security/keys/proc.c b/security/keys/proc.c
index 88e9a466940f..d3f6f2fd21db 100644
--- a/security/keys/proc.c
+++ b/security/keys/proc.c
@@ -218,7 +218,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
          * - the caller holds a spinlock, and thus the RCU read lock, making our
          *   access to __current_cred() safe
          */
-        rc = key_task_permission(key_ref, ctx.cred, KEY_VIEW);
+        rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW);
         if (rc < 0)
                 return 0;
 
diff --git a/security/security.c b/security/security.c
index 15b6928592ef..8e428ac90233 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1405,7 +1405,7 @@ void security_key_free(struct key *key)
 }
 
 int security_key_permission(key_ref_t key_ref,
-                            const struct cred *cred, key_perm_t perm)
+                            const struct cred *cred, unsigned perm)
 {
         return security_ops->key_permission(key_ref, cred, perm);
 }
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 4b34847208cc..eb5c307fcc9a 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -5704,7 +5704,7 @@ static void selinux_key_free(struct key *k)
 
 static int selinux_key_permission(key_ref_t key_ref,
                                   const struct cred *cred,
-                                  key_perm_t perm)
+                                  unsigned perm)
 {
         struct key *key;
         struct key_security_struct *ksec;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 14f52be78c75..c47dd8ca019c 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3506,7 +3506,7 @@ static void smack_key_free(struct key *key)
  * an error code otherwise
  */
 static int smack_key_permission(key_ref_t key_ref,
-                                const struct cred *cred, key_perm_t perm)
+                                const struct cred *cred, unsigned perm)
 {
         struct key *keyp;
         struct smk_audit_info ad;