-/* process_keys.c: management of a process's keyrings
+/* Management of a process's keyrings
*
- * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
/* session keyring create vs join semaphore */
static DEFINE_MUTEX(key_session_mutex);
+/* user keyring creation semaphore */
+static DEFINE_MUTEX(key_user_keyring_mutex);
+
/* the root user's tracking struct */
struct key_user root_key_user = {
.usage = ATOMIC_INIT(3),
- .consq = LIST_HEAD_INIT(root_key_user.consq),
+ .cons_lock = __MUTEX_INITIALIZER(root_key_user.cons_lock),
.lock = __SPIN_LOCK_UNLOCKED(root_key_user.lock),
.nkeys = ATOMIC_INIT(2),
.nikeys = ATOMIC_INIT(2),
.uid = 0,
};
-/* the root user's UID keyring */
-struct key root_user_keyring = {
- .usage = ATOMIC_INIT(1),
- .serial = 2,
- .type = &key_type_keyring,
- .user = &root_key_user,
- .sem = __RWSEM_INITIALIZER(root_user_keyring.sem),
- .perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
- .flags = 1 << KEY_FLAG_INSTANTIATED,
- .description = "_uid.0",
-#ifdef KEY_DEBUGGING
- .magic = KEY_DEBUG_MAGIC,
-#endif
-};
-
-/* the root user's default session keyring */
-struct key root_session_keyring = {
- .usage = ATOMIC_INIT(1),
- .serial = 1,
- .type = &key_type_keyring,
- .user = &root_key_user,
- .sem = __RWSEM_INITIALIZER(root_session_keyring.sem),
- .perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
- .flags = 1 << KEY_FLAG_INSTANTIATED,
- .description = "_uid_ses.0",
-#ifdef KEY_DEBUGGING
- .magic = KEY_DEBUG_MAGIC,
-#endif
-};
-
/*****************************************************************************/
/*
- * allocate the keyrings to be associated with a UID
+ * install user and user session keyrings for a particular UID
*/
-int alloc_uid_keyring(struct user_struct *user,
- struct task_struct *ctx)
+int install_user_keyrings(void)
{
+ struct user_struct *user = current->cred->user;
struct key *uid_keyring, *session_keyring;
char buf[20];
int ret;
- /* concoct a default session keyring */
- sprintf(buf, "_uid_ses.%u", user->uid);
+ kenter("%p{%u}", user, user->uid);
- session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx,
- KEY_ALLOC_IN_QUOTA, NULL);
- if (IS_ERR(session_keyring)) {
- ret = PTR_ERR(session_keyring);
- goto error;
+ if (user->uid_keyring) {
+ kleave(" = 0 [exist]");
+ return 0;
}
- /* and a UID specific keyring, pointed to by the default session
- * keyring */
- sprintf(buf, "_uid.%u", user->uid);
+ mutex_lock(&key_user_keyring_mutex);
+ ret = 0;
- uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx,
- KEY_ALLOC_IN_QUOTA, session_keyring);
- if (IS_ERR(uid_keyring)) {
- key_put(session_keyring);
- ret = PTR_ERR(uid_keyring);
- goto error;
+ if (!user->uid_keyring) {
+ /* get the UID-specific keyring
+ * - there may be one in existence already as it may have been
+ * pinned by a session, but the user_struct pointing to it
+ * may have been destroyed by setuid */
+ sprintf(buf, "_uid.%u", user->uid);
+
+ uid_keyring = find_keyring_by_name(buf, true);
+ if (IS_ERR(uid_keyring)) {
+ uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1,
+ current, KEY_ALLOC_IN_QUOTA,
+ NULL);
+ if (IS_ERR(uid_keyring)) {
+ ret = PTR_ERR(uid_keyring);
+ goto error;
+ }
+ }
+
+ /* get a default session keyring (which might also exist
+ * already) */
+ sprintf(buf, "_uid_ses.%u", user->uid);
+
+ session_keyring = find_keyring_by_name(buf, true);
+ if (IS_ERR(session_keyring)) {
+ session_keyring =
+ keyring_alloc(buf, user->uid, (gid_t) -1,
+ current, KEY_ALLOC_IN_QUOTA,
+ NULL);
+ if (IS_ERR(session_keyring)) {
+ ret = PTR_ERR(session_keyring);
+ goto error_release;
+ }
+
+ /* we install a link from the user session keyring to
+ * the user keyring */
+ ret = key_link(session_keyring, uid_keyring);
+ if (ret < 0)
+ goto error_release_both;
+ }
+
+ /* install the keyrings */
+ user->uid_keyring = uid_keyring;
+ user->session_keyring = session_keyring;
}
- /* install the keyrings */
- user->uid_keyring = uid_keyring;
- user->session_keyring = session_keyring;
- ret = 0;
+ mutex_unlock(&key_user_keyring_mutex);
+ kleave(" = 0");
+ return 0;
+error_release_both:
+ key_put(session_keyring);
+error_release:
+ key_put(uid_keyring);
error:
+ mutex_unlock(&key_user_keyring_mutex);
+ kleave(" = %d", ret);
return ret;
-
-} /* end alloc_uid_keyring() */
+}
/*****************************************************************************/
/*
/*
* install a fresh thread keyring, discarding the old one
*/
-int install_thread_keyring(struct task_struct *tsk)
+int install_thread_keyring(void)
{
+ struct task_struct *tsk = current;
struct key *keyring, *old;
char buf[20];
int ret;
sprintf(buf, "_tid.%u", tsk->pid);
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk,
+ keyring = keyring_alloc(buf, tsk->cred->uid, tsk->cred->gid, tsk,
KEY_ALLOC_QUOTA_OVERRUN, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
}
task_lock(tsk);
- old = tsk->thread_keyring;
- tsk->thread_keyring = keyring;
+ old = tsk->cred->thread_keyring;
+ tsk->cred->thread_keyring = keyring;
task_unlock(tsk);
ret = 0;
/*
* make sure a process keyring is installed
*/
-int install_process_keyring(struct task_struct *tsk)
+int install_process_keyring(void)
{
+ struct task_struct *tsk = current;
struct key *keyring;
char buf[20];
int ret;
if (!tsk->signal->process_keyring) {
sprintf(buf, "_pid.%u", tsk->tgid);
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk,
+ keyring = keyring_alloc(buf, tsk->cred->uid, tsk->cred->gid, tsk,
KEY_ALLOC_QUOTA_OVERRUN, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
* install a session keyring, discarding the old one
* - if a keyring is not supplied, an empty one is invented
*/
-static int install_session_keyring(struct task_struct *tsk,
- struct key *keyring)
+static int install_session_keyring(struct key *keyring)
{
+ struct task_struct *tsk = current;
unsigned long flags;
struct key *old;
char buf[20];
if (tsk->signal->session_keyring)
flags = KEY_ALLOC_IN_QUOTA;
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk,
+ keyring = keyring_alloc(buf, tsk->cred->uid, tsk->cred->gid, tsk,
flags, NULL);
if (IS_ERR(keyring))
return PTR_ERR(keyring);
*/
int copy_keys(unsigned long clone_flags, struct task_struct *tsk)
{
- key_check(tsk->thread_keyring);
- key_check(tsk->request_key_auth);
+ key_check(tsk->cred->thread_keyring);
+ key_check(tsk->cred->request_key_auth);
/* no thread keyring yet */
- tsk->thread_keyring = NULL;
+ tsk->cred->thread_keyring = NULL;
/* copy the request_key() authorisation for this thread */
- key_get(tsk->request_key_auth);
+ key_get(tsk->cred->request_key_auth);
return 0;
*/
void exit_keys(struct task_struct *tsk)
{
- key_put(tsk->thread_keyring);
- key_put(tsk->request_key_auth);
+ key_put(tsk->cred->thread_keyring);
+ key_put(tsk->cred->request_key_auth);
} /* end exit_keys() */
/* newly exec'd tasks don't get a thread keyring */
task_lock(tsk);
- old = tsk->thread_keyring;
- tsk->thread_keyring = NULL;
+ old = tsk->cred->thread_keyring;
+ tsk->cred->thread_keyring = NULL;
task_unlock(tsk);
key_put(old);
void key_fsuid_changed(struct task_struct *tsk)
{
/* update the ownership of the thread keyring */
- if (tsk->thread_keyring) {
- down_write(&tsk->thread_keyring->sem);
- tsk->thread_keyring->uid = tsk->fsuid;
- up_write(&tsk->thread_keyring->sem);
+ BUG_ON(!tsk->cred);
+ if (tsk->cred->thread_keyring) {
+ down_write(&tsk->cred->thread_keyring->sem);
+ tsk->cred->thread_keyring->uid = tsk->cred->fsuid;
+ up_write(&tsk->cred->thread_keyring->sem);
}
} /* end key_fsuid_changed() */
void key_fsgid_changed(struct task_struct *tsk)
{
/* update the ownership of the thread keyring */
- if (tsk->thread_keyring) {
- down_write(&tsk->thread_keyring->sem);
- tsk->thread_keyring->gid = tsk->fsgid;
- up_write(&tsk->thread_keyring->sem);
+ BUG_ON(!tsk->cred);
+ if (tsk->cred->thread_keyring) {
+ down_write(&tsk->cred->thread_keyring->sem);
+ tsk->cred->thread_keyring->gid = tsk->cred->fsgid;
+ up_write(&tsk->cred->thread_keyring->sem);
}
} /* end key_fsgid_changed() */
err = ERR_PTR(-EAGAIN);
/* search the thread keyring first */
- if (context->thread_keyring) {
+ if (context->cred->thread_keyring) {
key_ref = keyring_search_aux(
- make_key_ref(context->thread_keyring, 1),
+ make_key_ref(context->cred->thread_keyring, 1),
context, type, description, match);
if (!IS_ERR(key_ref))
goto found;
}
}
/* or search the user-session keyring */
- else {
+ else if (context->cred->user->session_keyring) {
key_ref = keyring_search_aux(
- make_key_ref(context->user->session_keyring, 1),
+ make_key_ref(context->cred->user->session_keyring, 1),
context, type, description, match);
if (!IS_ERR(key_ref))
goto found;
* search the keyrings of the process mentioned there
* - we don't permit access to request_key auth keys via this method
*/
- if (context->request_key_auth &&
+ if (context->cred->request_key_auth &&
context == current &&
type != &key_type_request_key_auth
) {
/* defend against the auth key being revoked */
- down_read(&context->request_key_auth->sem);
+ down_read(&context->cred->request_key_auth->sem);
- if (key_validate(context->request_key_auth) == 0) {
- rka = context->request_key_auth->payload.data;
+ if (key_validate(context->cred->request_key_auth) == 0) {
+ rka = context->cred->request_key_auth->payload.data;
key_ref = search_process_keyrings(type, description,
match, rka->context);
- up_read(&context->request_key_auth->sem);
+ up_read(&context->cred->request_key_auth->sem);
if (!IS_ERR(key_ref))
goto found;
break;
}
} else {
- up_read(&context->request_key_auth->sem);
+ up_read(&context->cred->request_key_auth->sem);
}
}
* - don't create special keyrings unless so requested
* - partially constructed keys aren't found unless requested
*/
-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 lookup_user_key(key_serial_t id, int create, int partial,
+ key_perm_t perm)
{
- key_ref_t key_ref, skey_ref;
+ struct request_key_auth *rka;
+ struct task_struct *t = current;
+ struct cred *cred = t->cred;
struct key *key;
+ key_ref_t key_ref, skey_ref;
int ret;
- if (!context)
- context = current;
-
key_ref = ERR_PTR(-ENOKEY);
switch (id) {
case KEY_SPEC_THREAD_KEYRING:
- if (!context->thread_keyring) {
+ if (!cred->thread_keyring) {
if (!create)
goto error;
- ret = install_thread_keyring(context);
+ ret = install_thread_keyring();
if (ret < 0) {
key = ERR_PTR(ret);
goto error;
}
}
- key = context->thread_keyring;
+ key = cred->thread_keyring;
atomic_inc(&key->usage);
key_ref = make_key_ref(key, 1);
break;
case KEY_SPEC_PROCESS_KEYRING:
- if (!context->signal->process_keyring) {
+ if (!t->signal->process_keyring) {
if (!create)
goto error;
- ret = install_process_keyring(context);
+ ret = install_process_keyring();
if (ret < 0) {
key = ERR_PTR(ret);
goto error;
}
}
- key = context->signal->process_keyring;
+ key = t->signal->process_keyring;
atomic_inc(&key->usage);
key_ref = make_key_ref(key, 1);
break;
case KEY_SPEC_SESSION_KEYRING:
- if (!context->signal->session_keyring) {
+ if (!t->signal->session_keyring) {
/* always install a session keyring upon access if one
* doesn't exist yet */
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error;
ret = install_session_keyring(
- context, context->user->session_keyring);
+ cred->user->session_keyring);
if (ret < 0)
goto error;
}
rcu_read_lock();
- key = rcu_dereference(context->signal->session_keyring);
+ key = rcu_dereference(t->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;
+ if (!cred->user->uid_keyring) {
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error;
+ }
+
+ key = cred->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;
+ if (!cred->user->session_keyring) {
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error;
+ }
+
+ key = cred->user->session_keyring;
atomic_inc(&key->usage);
key_ref = make_key_ref(key, 1);
break;
goto error;
case KEY_SPEC_REQKEY_AUTH_KEY:
- key = context->request_key_auth;
+ key = cred->request_key_auth;
if (!key)
goto error;
key_ref = make_key_ref(key, 1);
break;
+ case KEY_SPEC_REQUESTOR_KEYRING:
+ if (!cred->request_key_auth)
+ goto error;
+
+ down_read(&cred->request_key_auth->sem);
+ if (cred->request_key_auth->flags & KEY_FLAG_REVOKED) {
+ key_ref = ERR_PTR(-EKEYREVOKED);
+ key = NULL;
+ } else {
+ rka = cred->request_key_auth->payload.data;
+ key = rka->dest_keyring;
+ atomic_inc(&key->usage);
+ }
+ up_read(&cred->request_key_auth->sem);
+ if (!key)
+ goto error;
+ key_ref = make_key_ref(key, 1);
+ break;
+
default:
key_ref = ERR_PTR(-EINVAL);
if (id < 1)
key = key_lookup(id);
if (IS_ERR(key)) {
- key_ref = ERR_PTR(PTR_ERR(key));
+ key_ref = ERR_CAST(key);
goto error;
}
break;
}
- /* check the status */
- if (perm) {
+ if (!partial) {
+ ret = wait_for_key_construction(key, true);
+ switch (ret) {
+ case -ERESTARTSYS:
+ goto invalid_key;
+ default:
+ if (perm)
+ goto invalid_key;
+ case 0:
+ break;
+ }
+ } else if (perm) {
ret = key_validate(key);
if (ret < 0)
goto invalid_key;
goto invalid_key;
/* check the permissions */
- ret = key_task_permission(key_ref, context, perm);
+ ret = key_task_permission(key_ref, t, perm);
if (ret < 0)
goto invalid_key;
/* if no name is provided, install an anonymous keyring */
if (!name) {
- ret = install_session_keyring(tsk, NULL);
+ ret = install_session_keyring(NULL);
if (ret < 0)
goto error;
mutex_lock(&key_session_mutex);
/* look for an existing keyring of this name */
- keyring = find_keyring_by_name(name, 0);
+ keyring = find_keyring_by_name(name, false);
if (PTR_ERR(keyring) == -ENOKEY) {
/* not found - try and create a new one */
- keyring = keyring_alloc(name, tsk->uid, tsk->gid, tsk,
+ keyring = keyring_alloc(name, tsk->cred->uid, tsk->cred->gid, tsk,
KEY_ALLOC_IN_QUOTA, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
}
/* we've got a keyring - now to install it */
- ret = install_session_keyring(tsk, keyring);
+ ret = install_session_keyring(keyring);
if (ret < 0)
goto error2;
projects / linux-2.6-block.git / blobdiff