aboutsummaryrefslogtreecommitdiffstats
path: root/security/keys
diff options
context:
space:
mode:
Diffstat (limited to 'security/keys')
-rw-r--r--security/keys/internal.h49
-rw-r--r--security/keys/key.c25
-rw-r--r--security/keys/keyctl.c210
-rw-r--r--security/keys/keyring.c15
-rw-r--r--security/keys/permission.c29
-rw-r--r--security/keys/proc.c8
-rw-r--r--security/keys/process_keys.c469
-rw-r--r--security/keys/request_key.c135
-rw-r--r--security/keys/request_key_auth.c46
9 files changed, 542 insertions, 444 deletions
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 239098f0fd76..81932abefe7b 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -12,8 +12,8 @@
#ifndef _INTERNAL_H
#define _INTERNAL_H
+#include <linux/sched.h>
#include <linux/key-type.h>
-#include <linux/key-ui.h>
static inline __attribute__((format(printf, 1, 2)))
void no_printk(const char *fmt, ...)
@@ -26,7 +26,7 @@ void no_printk(const char *fmt, ...)
#define kleave(FMT, ...) \
printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
#define kdebug(FMT, ...) \
- printk(KERN_DEBUG "xxx" FMT"yyy\n", ##__VA_ARGS__)
+ printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
#else
#define kenter(FMT, ...) \
no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
@@ -82,6 +82,9 @@ extern struct mutex key_construction_mutex;
extern wait_queue_head_t request_key_conswq;
+extern struct key_type *key_type_lookup(const char *type);
+extern void key_type_put(struct key_type *ktype);
+
extern int __key_link(struct key *keyring, struct key *key);
extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
@@ -95,7 +98,7 @@ extern struct key *keyring_search_instkey(struct key *keyring,
typedef int (*key_match_func_t)(const struct key *, const void *);
extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
- struct task_struct *tsk,
+ const struct cred *cred,
struct key_type *type,
const void *description,
key_match_func_t match);
@@ -103,13 +106,13 @@ extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
extern key_ref_t search_process_keyrings(struct key_type *type,
const void *description,
key_match_func_t match,
- struct task_struct *tsk);
+ const struct cred *cred);
extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
-extern int install_user_keyrings(struct task_struct *tsk);
-extern int install_thread_keyring(struct task_struct *tsk);
-extern int install_process_keyring(struct task_struct *tsk);
+extern int install_user_keyrings(void);
+extern int install_thread_keyring_to_cred(struct cred *);
+extern int install_process_keyring_to_cred(struct cred *);
extern struct key *request_key_and_link(struct key_type *type,
const char *description,
@@ -119,12 +122,39 @@ extern struct key *request_key_and_link(struct key_type *type,
struct key *dest_keyring,
unsigned long flags);
+extern key_ref_t lookup_user_key(key_serial_t id, int create, int partial,
+ key_perm_t perm);
+
+extern long join_session_keyring(const char *name);
+
+/*
+ * check to see whether permission is granted to use a key in the desired way
+ */
+extern int key_task_permission(const key_ref_t key_ref,
+ const struct cred *cred,
+ key_perm_t perm);
+
+static inline int key_permission(const key_ref_t key_ref, key_perm_t 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 */
+
/*
* request_key authorisation
*/
struct request_key_auth {
struct key *target_key;
- struct task_struct *context;
+ struct key *dest_keyring;
+ const struct cred *cred;
void *callout_info;
size_t callout_len;
pid_t pid;
@@ -133,7 +163,8 @@ struct request_key_auth {
extern struct key_type key_type_request_key_auth;
extern struct key *request_key_auth_new(struct key *target,
const void *callout_info,
- size_t callout_len);
+ size_t callout_len,
+ struct key *dest_keyring);
extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
diff --git a/security/keys/key.c b/security/keys/key.c
index 14948cf83ef6..f76c8a546fd3 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -218,7 +218,7 @@ serial_exists:
* instantiate the key or discard it before returning
*/
struct key *key_alloc(struct key_type *type, const char *desc,
- uid_t uid, gid_t gid, struct task_struct *ctx,
+ uid_t uid, gid_t gid, const struct cred *cred,
key_perm_t perm, unsigned long flags)
{
struct key_user *user = NULL;
@@ -294,7 +294,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
#endif
/* let the security module know about the key */
- ret = security_key_alloc(key, ctx, flags);
+ ret = security_key_alloc(key, cred, flags);
if (ret < 0)
goto security_error;
@@ -391,7 +391,7 @@ static int __key_instantiate_and_link(struct key *key,
const void *data,
size_t datalen,
struct key *keyring,
- struct key *instkey)
+ struct key *authkey)
{
int ret, awaken;
@@ -421,8 +421,8 @@ static int __key_instantiate_and_link(struct key *key,
ret = __key_link(keyring, key);
/* disable the authorisation key */
- if (instkey)
- key_revoke(instkey);
+ if (authkey)
+ key_revoke(authkey);
}
}
@@ -444,14 +444,14 @@ int key_instantiate_and_link(struct key *key,
const void *data,
size_t datalen,
struct key *keyring,
- struct key *instkey)
+ struct key *authkey)
{
int ret;
if (keyring)
down_write(&keyring->sem);
- ret = __key_instantiate_and_link(key, data, datalen, keyring, instkey);
+ ret = __key_instantiate_and_link(key, data, datalen, keyring, authkey);
if (keyring)
up_write(&keyring->sem);
@@ -469,7 +469,7 @@ EXPORT_SYMBOL(key_instantiate_and_link);
int key_negate_and_link(struct key *key,
unsigned timeout,
struct key *keyring,
- struct key *instkey)
+ struct key *authkey)
{
struct timespec now;
int ret, awaken;
@@ -504,8 +504,8 @@ int key_negate_and_link(struct key *key,
ret = __key_link(keyring, key);
/* disable the authorisation key */
- if (instkey)
- key_revoke(instkey);
+ if (authkey)
+ key_revoke(authkey);
}
mutex_unlock(&key_construction_mutex);
@@ -743,6 +743,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
key_perm_t perm,
unsigned long flags)
{
+ const struct cred *cred = current_cred();
struct key_type *ktype;
struct key *keyring, *key = NULL;
key_ref_t key_ref;
@@ -802,8 +803,8 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
}
/* allocate a new key */
- key = key_alloc(ktype, description, current->fsuid, current->fsgid,
- current, perm, flags);
+ key = key_alloc(ktype, description, cred->fsuid, cred->fsgid, cred,
+ perm, flags);
if (IS_ERR(key)) {
key_ref = ERR_CAST(key);
goto error_3;
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index acc9c89e40a8..7c72baa02f2e 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -103,7 +103,7 @@ asmlinkage long sys_add_key(const char __user *_type,
}
/* find the target keyring (which must be writable) */
- keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
+ keyring_ref = lookup_user_key(ringid, 1, 0, KEY_WRITE);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
goto error3;
@@ -185,7 +185,7 @@ asmlinkage long sys_request_key(const char __user *_type,
/* get the destination keyring if specified */
dest_ref = NULL;
if (destringid) {
- dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
+ dest_ref = lookup_user_key(destringid, 1, 0, KEY_WRITE);
if (IS_ERR(dest_ref)) {
ret = PTR_ERR(dest_ref);
goto error3;
@@ -235,7 +235,7 @@ long keyctl_get_keyring_ID(key_serial_t id, int create)
key_ref_t key_ref;
long ret;
- key_ref = lookup_user_key(NULL, id, create, 0, KEY_SEARCH);
+ key_ref = lookup_user_key(id, create, 0, KEY_SEARCH);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
@@ -308,7 +308,7 @@ long keyctl_update_key(key_serial_t id,
}
/* find the target key (which must be writable) */
- key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
+ key_ref = lookup_user_key(id, 0, 0, KEY_WRITE);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error2;
@@ -336,7 +336,7 @@ long keyctl_revoke_key(key_serial_t id)
key_ref_t key_ref;
long ret;
- key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
+ key_ref = lookup_user_key(id, 0, 0, KEY_WRITE);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
@@ -362,7 +362,7 @@ long keyctl_keyring_clear(key_serial_t ringid)
key_ref_t keyring_ref;
long ret;
- keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
+ keyring_ref = lookup_user_key(ringid, 1, 0, KEY_WRITE);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
goto error;
@@ -388,13 +388,13 @@ 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(NULL, ringid, 1, 0, KEY_WRITE);
+ keyring_ref = lookup_user_key(ringid, 1, 0, KEY_WRITE);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
goto error;
}
- key_ref = lookup_user_key(NULL, id, 1, 0, KEY_LINK);
+ key_ref = lookup_user_key(id, 1, 0, KEY_LINK);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error2;
@@ -422,13 +422,13 @@ 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(NULL, ringid, 0, 0, KEY_WRITE);
+ keyring_ref = lookup_user_key(ringid, 0, 0, KEY_WRITE);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
goto error;
}
- key_ref = lookup_user_key(NULL, id, 0, 0, 0);
+ key_ref = lookup_user_key(id, 0, 0, 0);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error2;
@@ -464,7 +464,7 @@ long keyctl_describe_key(key_serial_t keyid,
char *tmpbuf;
long ret;
- key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW);
+ key_ref = lookup_user_key(keyid, 0, 1, KEY_VIEW);
if (IS_ERR(key_ref)) {
/* viewing a key under construction is permitted if we have the
* authorisation token handy */
@@ -472,7 +472,7 @@ long keyctl_describe_key(key_serial_t keyid,
instkey = key_get_instantiation_authkey(keyid);
if (!IS_ERR(instkey)) {
key_put(instkey);
- key_ref = lookup_user_key(NULL, keyid,
+ key_ref = lookup_user_key(keyid,
0, 1, 0);
if (!IS_ERR(key_ref))
goto okay;
@@ -557,7 +557,7 @@ long keyctl_keyring_search(key_serial_t ringid,
}
/* get the keyring at which to begin the search */
- keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH);
+ keyring_ref = lookup_user_key(ringid, 0, 0, KEY_SEARCH);
if (IS_ERR(keyring_ref)) {
ret = PTR_ERR(keyring_ref);
goto error2;
@@ -566,7 +566,7 @@ long keyctl_keyring_search(key_serial_t ringid,
/* get the destination keyring if specified */
dest_ref = NULL;
if (destringid) {
- dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
+ dest_ref = lookup_user_key(destringid, 1, 0, KEY_WRITE);
if (IS_ERR(dest_ref)) {
ret = PTR_ERR(dest_ref);
goto error3;
@@ -636,7 +636,7 @@ long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
long ret;
/* find the key first */
- key_ref = lookup_user_key(NULL, keyid, 0, 0, 0);
+ key_ref = lookup_user_key(keyid, 0, 0, 0);
if (IS_ERR(key_ref)) {
ret = -ENOKEY;
goto error;
@@ -699,7 +699,7 @@ long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
if (uid == (uid_t) -1 && gid == (gid_t) -1)
goto error;
- key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+ key_ref = lookup_user_key(id, 1, 1, KEY_SETATTR);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
@@ -804,7 +804,7 @@ long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
goto error;
- key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+ key_ref = lookup_user_key(id, 1, 1, KEY_SETATTR);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
@@ -817,7 +817,7 @@ long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
down_write(&key->sem);
/* if we're not the sysadmin, we can only change a key that we own */
- if (capable(CAP_SYS_ADMIN) || key->uid == current->fsuid) {
+ if (capable(CAP_SYS_ADMIN) || key->uid == current_fsuid()) {
key->perm = perm;
ret = 0;
}
@@ -829,6 +829,60 @@ error:
} /* end keyctl_setperm_key() */
+/*
+ * get the destination keyring for instantiation
+ */
+static long get_instantiation_keyring(key_serial_t ringid,
+ struct request_key_auth *rka,
+ struct key **_dest_keyring)
+{
+ key_ref_t dkref;
+
+ /* just return a NULL pointer if we weren't asked to make a link */
+ if (ringid == 0) {
+ *_dest_keyring = NULL;
+ return 0;
+ }
+
+ /* if a specific keyring is nominated by ID, then use that */
+ if (ringid > 0) {
+ dkref = lookup_user_key(ringid, 1, 0, KEY_WRITE);
+ if (IS_ERR(dkref))
+ return PTR_ERR(dkref);
+ *_dest_keyring = key_ref_to_ptr(dkref);
+ return 0;
+ }
+
+ if (ringid == KEY_SPEC_REQKEY_AUTH_KEY)
+ return -EINVAL;
+
+ /* otherwise specify the destination keyring recorded in the
+ * authorisation key (any KEY_SPEC_*_KEYRING) */
+ if (ringid >= KEY_SPEC_REQUESTOR_KEYRING) {
+ *_dest_keyring = rka->dest_keyring;
+ return 0;
+ }
+
+ return -ENOKEY;
+}
+
+/*
+ * change the request_key authorisation key on the current process
+ */
+static int keyctl_change_reqkey_auth(struct key *key)
+{
+ struct cred *new;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ key_put(new->request_key_auth);
+ new->request_key_auth = key_get(key);
+
+ return commit_creds(new);
+}
+
/*****************************************************************************/
/*
* instantiate the key with the specified payload, and, if one is given, link
@@ -839,13 +893,15 @@ long keyctl_instantiate_key(key_serial_t id,
size_t plen,
key_serial_t ringid)
{
+ const struct cred *cred = current_cred();
struct request_key_auth *rka;
- struct key *instkey;
- key_ref_t keyring_ref;
+ struct key *instkey, *dest_keyring;
void *payload;
long ret;
bool vm = false;
+ kenter("%d,,%zu,%d", id, plen, ringid);
+
ret = -EINVAL;
if (plen > 1024 * 1024 - 1)
goto error;
@@ -853,7 +909,7 @@ long keyctl_instantiate_key(key_serial_t id,
/* the appropriate instantiation authorisation key must have been
* assumed before calling this */
ret = -EPERM;
- instkey = current->request_key_auth;
+ instkey = cred->request_key_auth;
if (!instkey)
goto error;
@@ -883,28 +939,20 @@ long keyctl_instantiate_key(key_serial_t id,
/* find the destination keyring amongst those belonging to the
* requesting task */
- keyring_ref = NULL;
- if (ringid) {
- keyring_ref = lookup_user_key(rka->context, ringid, 1, 0,
- KEY_WRITE);
- if (IS_ERR(keyring_ref)) {
- ret = PTR_ERR(keyring_ref);
- goto error2;
- }
- }
+ ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
+ if (ret < 0)
+ goto error2;
/* instantiate the key and link it into a keyring */
ret = key_instantiate_and_link(rka->target_key, payload, plen,
- key_ref_to_ptr(keyring_ref), instkey);
+ dest_keyring, instkey);
- key_ref_put(keyring_ref);
+ key_put(dest_keyring);
/* discard the assumed authority if it's just been disabled by
* instantiation of the key */
- if (ret == 0) {
- key_put(current->request_key_auth);
- current->request_key_auth = NULL;
- }
+ if (ret == 0)
+ keyctl_change_reqkey_auth(NULL);
error2:
if (!vm)
@@ -923,15 +971,17 @@ error:
*/
long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
{
+ const struct cred *cred = current_cred();
struct request_key_auth *rka;
- struct key *instkey;
- key_ref_t keyring_ref;
+ struct key *instkey, *dest_keyring;
long ret;
+ kenter("%d,%u,%d", id, timeout, ringid);
+
/* the appropriate instantiation authorisation key must have been
* assumed before calling this */
ret = -EPERM;
- instkey = current->request_key_auth;
+ instkey = cred->request_key_auth;
if (!instkey)
goto error;
@@ -941,27 +991,20 @@ 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_ref = NULL;
- if (ringid) {
- keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
- if (IS_ERR(keyring_ref)) {
- ret = PTR_ERR(keyring_ref);
- goto error;
- }
- }
+ ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
+ if (ret < 0)
+ goto error;
/* instantiate the key and link it into a keyring */
ret = key_negate_and_link(rka->target_key, timeout,
- key_ref_to_ptr(keyring_ref), instkey);
+ dest_keyring, instkey);
- key_ref_put(keyring_ref);
+ key_put(dest_keyring);
/* discard the assumed authority if it's just been disabled by
* instantiation of the key */
- if (ret == 0) {
- key_put(current->request_key_auth);
- current->request_key_auth = NULL;
- }
+ if (ret == 0)
+ keyctl_change_reqkey_auth(NULL);
error:
return ret;
@@ -975,35 +1018,56 @@ error:
*/
long keyctl_set_reqkey_keyring(int reqkey_defl)
{
- int ret;
+ struct cred *new;
+ int ret, old_setting;
+
+ old_setting = current_cred_xxx(jit_keyring);
+
+ if (reqkey_defl == KEY_REQKEY_DEFL_NO_CHANGE)
+ return old_setting;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
switch (reqkey_defl) {
case KEY_REQKEY_DEFL_THREAD_KEYRING:
- ret = install_thread_keyring(current);
+ ret = install_thread_keyring_to_cred(new);
if (ret < 0)
- return ret;
+ goto error;
goto set;
case KEY_REQKEY_DEFL_PROCESS_KEYRING:
- ret = install_process_keyring(current);
- if (ret < 0)
- return ret;
+ ret = install_process_keyring_to_cred(new);
+ if (ret < 0) {
+ if (ret != -EEXIST)
+ goto error;
+ ret = 0;
+ }
+ goto set;
case KEY_REQKEY_DEFL_DEFAULT:
case KEY_REQKEY_DEFL_SESSION_KEYRING:
case KEY_REQKEY_DEFL_USER_KEYRING:
case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
- set:
- current->jit_keyring = reqkey_defl;
+ case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
+ goto set;
case KEY_REQKEY_DEFL_NO_CHANGE:
- return current->jit_keyring;
-
case KEY_REQKEY_DEFL_GROUP_KEYRING:
default:
- return -EINVAL;
+ ret = -EINVAL;
+ goto error;
}
+set:
+ new->jit_keyring = reqkey_defl;
+ commit_creds(new);
+ return old_setting;
+error:
+ abort_creds(new);
+ return -EINVAL;
+
} /* end keyctl_set_reqkey_keyring() */
/*****************************************************************************/
@@ -1018,7 +1082,7 @@ long keyctl_set_timeout(key_serial_t id, unsigned timeout)
time_t expiry;
long ret;
- key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
+ key_ref = lookup_user_key(id, 1, 1, KEY_SETATTR);
if (IS_ERR(key_ref)) {
ret = PTR_ERR(key_ref);
goto error;
@@ -1062,9 +1126,7 @@ long keyctl_assume_authority(key_serial_t id)
/* we divest ourselves of authority if given an ID of 0 */
if (id == 0) {
- key_put(current->request_key_auth);
- current->request_key_auth = NULL;
- ret = 0;
+ ret = keyctl_change_reqkey_auth(NULL);
goto error;
}
@@ -1079,10 +1141,12 @@ long keyctl_assume_authority(key_serial_t id)
goto error;
}
- key_put(current->request_key_auth);
- current->request_key_auth = authkey;
- ret = authkey->serial;
+ ret = keyctl_change_reqkey_auth(authkey);
+ if (ret < 0)
+ goto error;
+ key_put(authkey);
+ ret = authkey->serial;
error:
return ret;
@@ -1105,7 +1169,7 @@ long keyctl_get_security(key_serial_t keyid,
char *context;
long ret;
- key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW);
+ key_ref = lookup_user_key(keyid, 0, 1, KEY_VIEW);
if (IS_ERR(key_ref)) {
if (PTR_ERR(key_ref) != -EACCES)
return PTR_ERR(key_ref);
@@ -1117,7 +1181,7 @@ long keyctl_get_security(key_serial_t keyid,
return PTR_ERR(key_ref);
key_put(instkey);
- key_ref = lookup_user_key(NULL, keyid, 0, 1, 0);
+ key_ref = lookup_user_key(keyid, 0, 1, 0);
if (IS_ERR(key_ref))
return PTR_ERR(key_ref);
}
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index a9ab8affc092..ed851574d073 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -16,6 +16,7 @@
#include <linux/security.h>
#include <linux/seq_file.h>
#include <linux/err.h>
+#include <keys/keyring-type.h>
#include <asm/uaccess.h>
#include "internal.h"
@@ -244,14 +245,14 @@ static long keyring_read(const struct key *keyring,
* allocate a keyring and link into the destination keyring
*/
struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
- struct task_struct *ctx, unsigned long flags,
+ const struct cred *cred, unsigned long flags,
struct key *dest)
{
struct key *keyring;
int ret;
keyring = key_alloc(&key_type_keyring, description,
- uid, gid, ctx,
+ uid, gid, cred,
(KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
flags);
@@ -280,7 +281,7 @@ struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
* - we propagate the possession attribute from the keyring ref to the key ref
*/
key_ref_t keyring_search_aux(key_ref_t keyring_ref,
- struct task_struct *context,
+ const struct cred *cred,
struct key_type *type,
const void *description,
key_match_func_t match)
@@ -303,7 +304,7 @@ key_ref_t keyring_search_aux(key_ref_t keyring_ref,
key_check(keyring);
/* top keyring must have search permission to begin the search */
- err = key_task_permission(keyring_ref, context, KEY_SEARCH);
+ err = key_task_permission(keyring_ref, cred, KEY_SEARCH);
if (err < 0) {
key_ref = ERR_PTR(err);
goto error;
@@ -376,7 +377,7 @@ descend:
/* key must have search permissions */
if (key_task_permission(make_key_ref(key, possessed),
- context, KEY_SEARCH) < 0)
+ cred, KEY_SEARCH) < 0)
continue;
/* we set a different error code if we pass a negative key */
@@ -403,7 +404,7 @@ ascend:
continue;
if (key_task_permission(make_key_ref(key, possessed),
- context, KEY_SEARCH) < 0)
+ cred, KEY_SEARCH) < 0)
continue;
/* stack the current position */
@@ -458,7 +459,7 @@ key_ref_t keyring_search(key_ref_t keyring,
if (!type->match)
return ERR_PTR(-ENOKEY);
- return keyring_search_aux(keyring, current,
+ return keyring_search_aux(keyring, current->cred,
type, description, type->match);
} /* end keyring_search() */
diff --git a/security/keys/permission.c b/security/keys/permission.c
index 3b41f9b52537..5d9fc7b93f2e 100644
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -14,12 +14,19 @@
#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
+/**
+ * key_task_permission - Check a key can be used
+ * @key_ref: The key to check
+ * @cred: The credentials to use
+ * @perm: The permissions to check for
+ *
+ * Check to see whether permission is granted to use a key in the desired way,
+ * but permit the security modules to override.
+ *
+ * The caller must hold either a ref on cred or must hold the RCU readlock or a
+ * spinlock.
*/
-int key_task_permission(const key_ref_t key_ref,
- struct task_struct *context,
+int key_task_permission(const key_ref_t key_ref, const struct cred *cred,
key_perm_t perm)
{
struct key *key;
@@ -29,7 +36,7 @@ int key_task_permission(const key_ref_t key_ref,
key = key_ref_to_ptr(key_ref);
/* use the second 8-bits of permissions for keys the caller owns */
- if (key->uid == context->fsuid) {
+ if (key->uid == cred->fsuid) {
kperm = key->perm >> 16;
goto use_these_perms;
}
@@ -37,15 +44,12 @@ int key_task_permission(const key_ref_t key_ref,
/* 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) {
+ if (key->gid == cred->fsgid) {
kperm = key->perm >> 8;
goto use_these_perms;
}
- task_lock(context);
- ret = groups_search(context->group_info, key->gid);
- task_unlock(context);
-
+ ret = groups_search(cred->group_info, key->gid);
if (ret) {
kperm = key->perm >> 8;
goto use_these_perms;
@@ -56,6 +60,7 @@ int key_task_permission(const key_ref_t key_ref,
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
*/
@@ -68,7 +73,7 @@ use_these_perms:
return -EACCES;
/* let LSM be the final arbiter */
- return security_key_permission(key_ref, context, perm);
+ return security_key_permission(key_ref, cred, perm);
} /* end key_task_permission() */
diff --git a/security/keys/proc.c b/security/keys/proc.c
index f619170da760..7f508def50e3 100644
--- a/security/keys/proc.c
+++ b/security/keys/proc.c
@@ -136,8 +136,12 @@ static int proc_keys_show(struct seq_file *m, void *v)
int rc;
/* check whether the current task is allowed to view the key (assuming
- * non-possession) */
- rc = key_task_permission(make_key_ref(key, 0), current, KEY_VIEW);
+ * non-possession)
+ * - the caller holds a spinlock, and thus the RCU read lock, making our
+ * access to __current_cred() safe
+ */
+ rc = key_task_permission(make_key_ref(key, 0), current_cred(),
+ KEY_VIEW);
if (rc < 0)
return 0;
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 45b240af6dbe..2f5d89e92b85 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -40,13 +40,17 @@ struct key_user root_key_user = {
/*
* install user and user session keyrings for a particular UID
*/
-int install_user_keyrings(struct task_struct *tsk)
+int install_user_keyrings(void)
{
- struct user_struct *user = tsk->user;
+ struct user_struct *user;
+ const struct cred *cred;
struct key *uid_keyring, *session_keyring;
char buf[20];
int ret;
+ cred = current_cred();
+ user = cred->user;
+
kenter("%p{%u}", user, user->uid);
if (user->uid_keyring) {
@@ -67,7 +71,7 @@ int install_user_keyrings(struct task_struct *tsk)
uid_keyring = find_keyring_by_name(buf, true);
if (IS_ERR(uid_keyring)) {
uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1,
- tsk, KEY_ALLOC_IN_QUOTA,
+ cred, KEY_ALLOC_IN_QUOTA,
NULL);
if (IS_ERR(uid_keyring)) {
ret = PTR_ERR(uid_keyring);
@@ -83,7 +87,7 @@ int install_user_keyrings(struct task_struct *tsk)
if (IS_ERR(session_keyring)) {
session_keyring =
keyring_alloc(buf, user->uid, (gid_t) -1,
- tsk, KEY_ALLOC_IN_QUOTA, NULL);
+ cred, KEY_ALLOC_IN_QUOTA, NULL);
if (IS_ERR(session_keyring)) {
ret = PTR_ERR(session_keyring);
goto error_release;
@@ -115,140 +119,128 @@ error:
return ret;
}
-/*****************************************************************************/
/*
- * deal with the UID changing
+ * install a fresh thread keyring directly to new credentials
*/
-void switch_uid_keyring(struct user_struct *new_user)
+int install_thread_keyring_to_cred(struct cred *new)
{
-#if 0 /* do nothing for now */
- struct key *old;
-
- /* switch to the new user's session keyring if we were running under
- * root's default session keyring */
- if (new_user->uid != 0 &&
- current->session_keyring == &root_session_keyring
- ) {
- atomic_inc(&new_user->session_keyring->usage);
-
- task_lock(current);
- old = current->session_keyring;
- current->session_keyring = new_user->session_keyring;
- task_unlock(current);
+ struct key *keyring;
- key_put(old);
- }
-#endif
+ keyring = keyring_alloc("_tid", new->uid, new->gid, new,
+ KEY_ALLOC_QUOTA_OVERRUN, NULL);
+ if (IS_ERR(keyring))
+ return PTR_ERR(keyring);
-} /* end switch_uid_keyring() */
+ new->thread_keyring = keyring;
+ return 0;
+}
-/*****************************************************************************/
/*
* install a fresh thread keyring, discarding the old one
*/
-int install_thread_keyring(struct task_struct *tsk)
+static int install_thread_keyring(void)
{
- struct key *keyring, *old;
- char buf[20];
+ struct cred *new;
int ret;
- sprintf(buf, "_tid.%u", tsk->pid);
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk,
- KEY_ALLOC_QUOTA_OVERRUN, NULL);
- if (IS_ERR(keyring)) {
- ret = PTR_ERR(keyring);
- goto error;
+ BUG_ON(new->thread_keyring);
+
+ ret = install_thread_keyring_to_cred(new);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret;
}
- task_lock(tsk);
- old = tsk->thread_keyring;
- tsk->thread_keyring = keyring;
- task_unlock(tsk);
+ return commit_creds(new);
+}
- ret = 0;
+/*
+ * install a process keyring directly to a credentials struct
+ * - returns -EEXIST if there was already a process keyring, 0 if one installed,
+ * and other -ve on any other error
+ */
+int install_process_keyring_to_cred(struct cred *new)
+{
+ struct key *keyring;
+ int ret;
- key_put(old);
-error:
+ if (new->tgcred->process_keyring)
+ return -EEXIST;
+
+ keyring = keyring_alloc("_pid", new->uid, new->gid,
+ new, KEY_ALLOC_QUOTA_OVERRUN, NULL);
+ if (IS_ERR(keyring))
+ return PTR_ERR(keyring);
+
+ spin_lock_irq(&new->tgcred->lock);
+ if (!new->tgcred->process_keyring) {
+ new->tgcred->process_keyring = keyring;
+ keyring = NULL;
+ ret = 0;
+ } else {
+ ret = -EEXIST;
+ }
+ spin_unlock_irq(&new->tgcred->lock);
+ key_put(keyring);
return ret;
+}
-} /* end install_thread_keyring() */
-
-/*****************************************************************************/
/*
* make sure a process keyring is installed
+ * - we
*/
-int install_process_keyring(struct task_struct *tsk)
+static int install_process_keyring(void)
{
- struct key *keyring;
- char buf[20];
+ struct cred *new;
int ret;
- might_sleep();
-
- if (!tsk->signal->process_keyring) {
- sprintf(buf, "_pid.%u", tsk->tgid);
-
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk,
- KEY_ALLOC_QUOTA_OVERRUN, NULL);
- if (IS_ERR(keyring)) {
- ret = PTR_ERR(keyring);
- goto error;
- }
-
- /* attach keyring */
- spin_lock_irq(&tsk->sighand->siglock);
- if (!tsk->signal->process_keyring) {
- tsk->signal->process_keyring = keyring;
- keyring = NULL;
- }
- spin_unlock_irq(&tsk->sighand->siglock);
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
- key_put(keyring);
+ ret = install_process_keyring_to_cred(new);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret != -EEXIST ?: 0;
}
- ret = 0;
-error:
- return ret;
-
-} /* end install_process_keyring() */
+ return commit_creds(new);
+}
-/*****************************************************************************/
/*
- * install a session keyring, discarding the old one
- * - if a keyring is not supplied, an empty one is invented
+ * install a session keyring directly to a credentials struct
*/
-static int install_session_keyring(struct task_struct *tsk,
- struct key *keyring)
+static int install_session_keyring_to_cred(struct cred *cred,
+ struct key *keyring)
{
unsigned long flags;
struct key *old;
- char buf[20];
might_sleep();
/* create an empty session keyring */
if (!keyring) {
- sprintf(buf, "_ses.%u", tsk->tgid);
-
flags = KEY_ALLOC_QUOTA_OVERRUN;
- if (tsk->signal->session_keyring)
+ if (cred->tgcred->session_keyring)
flags = KEY_ALLOC_IN_QUOTA;
- keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk,
- flags, NULL);
+ keyring = keyring_alloc("_ses", cred->uid, cred->gid,
+ cred, flags, NULL);
if (IS_ERR(keyring))
return PTR_ERR(keyring);
- }
- else {
+ } else {
atomic_inc(&keyring->usage);
}
/* install the keyring */
- spin_lock_irq(&tsk->sighand->siglock);
- old = tsk->signal->session_keyring;
- rcu_assign_pointer(tsk->signal->session_keyring, keyring);
- spin_unlock_irq(&tsk->sighand->siglock);
+ spin_lock_irq(&cred->tgcred->lock);
+ old = cred->tgcred->session_keyring;
+ rcu_assign_pointer(cred->tgcred->session_keyring, keyring);
+ spin_unlock_irq(&cred->tgcred->lock);
/* we're using RCU on the pointer, but there's no point synchronising
* on it if it didn't previously point to anything */
@@ -258,110 +250,29 @@ static int install_session_keyring(struct task_struct *tsk,
}
return 0;
+}
-} /* end install_session_keyring() */
-
-/*****************************************************************************/
-/*
- * copy the keys in a thread group for fork without CLONE_THREAD
- */
-int copy_thread_group_keys(struct task_struct *tsk)
-{
- key_check(current->thread_group->session_keyring);
- key_check(current->thread_group->process_keyring);
-
- /* no process keyring yet */
- tsk->signal->process_keyring = NULL;
-
- /* same session keyring */
- rcu_read_lock();
- tsk->signal->session_keyring =
- key_get(rcu_dereference(current->signal->session_keyring));
- rcu_read_unlock();
-
- return 0;
-
-} /* end copy_thread_group_keys() */
-
-/*****************************************************************************/
-/*
- * copy the keys for fork
- */
-int copy_keys(unsigned long clone_flags, struct task_struct *tsk)
-{
- key_check(tsk->thread_keyring);
- key_check(tsk->request_key_auth);
-
- /* no thread keyring yet */
- tsk->thread_keyring = NULL;
-
- /* copy the request_key() authorisation for this thread */
- key_get(tsk->request_key_auth);
-
- return 0;
-
-} /* end copy_keys() */
-
-/*****************************************************************************/
-/*
- * dispose of thread group keys upon thread group destruction
- */
-void exit_thread_group_keys(struct signal_struct *tg)
-{
- key_put(tg->session_keyring);
- key_put(tg->process_keyring);
-
-} /* end exit_thread_group_keys() */
-
-/*****************************************************************************/
-/*
- * dispose of per-thread keys upon thread exit
- */
-void exit_keys(struct task_struct *tsk)
-{
- key_put(tsk->thread_keyring);
- key_put(tsk->request_key_auth);
-
-} /* end exit_keys() */
-
-/*****************************************************************************/
/*
- * deal with execve()
+ * install a session keyring, discarding the old one
+ * - if a keyring is not supplied, an empty one is invented
*/
-int exec_keys(struct task_struct *tsk)
+static int install_session_keyring(struct key *keyring)
{
- struct key *old;
-
- /* newly exec'd tasks don't get a thread keyring */
- task_lock(tsk);
- old = tsk->thread_keyring;
- tsk->thread_keyring = NULL;
- task_unlock(tsk);
-
- key_put(old);
-
- /* discard the process keyring from a newly exec'd task */
- spin_lock_irq(&tsk->sighand->siglock);
- old = tsk->signal->process_keyring;
- tsk->signal->process_keyring = NULL;
- spin_unlock_irq(&tsk->sighand->siglock);
-
- key_put(old);
-
- return 0;
+ struct cred *new;
+ int ret;
-} /* end exec_keys() */
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
-/*****************************************************************************/
-/*
- * deal with SUID programs
- * - we might want to make this invent a new session keyring
- */
-int suid_keys(struct task_struct *tsk)
-{
- return 0;
+ ret = install_session_keyring_to_cred(new, NULL);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret;
+ }
-} /* end suid_keys() */
+ return commit_creds(new);
+}
/*****************************************************************************/
/*
@@ -370,10 +281,11 @@ int suid_keys(struct task_struct *tsk)
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() */
@@ -385,10 +297,11 @@ void key_fsuid_changed(struct task_struct *tsk)
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() */
@@ -404,7 +317,7 @@ void key_fsgid_changed(struct task_struct *tsk)
key_ref_t search_process_keyrings(struct key_type *type,
const void *description,
key_match_func_t match,
- struct task_struct *context)
+ const struct cred *cred)
{
struct request_key_auth *rka;
key_ref_t key_ref, ret, err;
@@ -423,10 +336,10 @@ key_ref_t search_process_keyrings(struct key_type *type,
err = ERR_PTR(-EAGAIN);
/* search the thread keyring first */
- if (context->thread_keyring) {
+ if (cred->thread_keyring) {
key_ref = keyring_search_aux(
- make_key_ref(context->thread_keyring, 1),
- context, type, description, match);
+ make_key_ref(cred->thread_keyring, 1),
+ cred, type, description, match);
if (!IS_ERR(key_ref))
goto found;
@@ -444,10 +357,10 @@ key_ref_t search_process_keyrings(struct key_type *type,
}
/* search the process keyring second */
- if (context->signal->process_keyring) {
+ if (cred->tgcred->process_keyring) {
key_ref = keyring_search_aux(
- make_key_ref(context->signal->process_keyring, 1),
- context, type, description, match);
+ make_key_ref(cred->tgcred->process_keyring, 1),
+ cred, type, description, match);
if (!IS_ERR(key_ref))
goto found;
@@ -465,13 +378,13 @@ key_ref_t search_process_keyrings(struct key_type *type,
}
/* search the session keyring */
- if (context->signal->session_keyring) {
+ if (cred->tgcred->session_keyring) {
rcu_read_lock();
key_ref = keyring_search_aux(
make_key_ref(rcu_dereference(
- context->signal->session_keyring),
+ cred->tgcred->session_keyring),
1),
- context, type, description, match);
+ cred, type, description, match);
rcu_read_unlock();
if (!IS_ERR(key_ref))
@@ -490,10 +403,10 @@ key_ref_t search_process_keyrings(struct key_type *type,
}
}
/* or search the user-session keyring */
- else if (context->user->session_keyring) {
+ else if (cred->user->session_keyring) {
key_ref = keyring_search_aux(
- make_key_ref(context->user->session_keyring, 1),
- context, type, description, match);
+ make_key_ref(cred->user->session_keyring, 1),
+ cred, type, description, match);
if (!IS_ERR(key_ref))
goto found;
@@ -514,20 +427,20 @@ key_ref_t search_process_keyrings(struct key_type *type,
* 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 &&
- context == current &&
+ if (cred->request_key_auth &&
+ cred == current_cred() &&
type != &key_type_request_key_auth
) {
/* defend against the auth key being revoked */
- down_read(&context->request_key_auth->sem);
+ down_read(&cred->request_key_auth->sem);
- if (key_validate(context->request_key_auth) == 0) {
- rka = context->request_key_auth->payload.data;
+ if (key_validate(cred->request_key_auth) == 0) {
+ rka = cred->request_key_auth->payload.data;
key_ref = search_process_keyrings(type, description,
- match, rka->context);
+ match, rka->cred);
- up_read(&context->request_key_auth->sem);
+ up_read(&cred->request_key_auth->sem);
if (!IS_ERR(key_ref))
goto found;
@@ -544,7 +457,7 @@ key_ref_t search_process_keyrings(struct key_type *type,
break;
}
} else {
- up_read(&context->request_key_auth->sem);
+ up_read(&cred->request_key_auth->sem);
}
}
@@ -572,93 +485,98 @@ static int lookup_user_key_possessed(const struct key *key, const void *target)
* - 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;
+ const struct cred *cred;
struct key *key;
+ key_ref_t key_ref, skey_ref;
int ret;
- if (!context)
- context = current;
-
+try_again:
+ cred = get_current_cred();
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;
}
+ goto reget_creds;
}
- 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 (!cred->tgcred->process_keyring) {
if (!create)
goto error;
- ret = install_process_keyring(context);
+ ret = install_process_keyring();
if (ret < 0) {
key = ERR_PTR(ret);
goto error;
}
+ goto reget_creds;
}
- key = context->signal->process_keyring;
+ key = cred->tgcred->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 (!cred->tgcred->session_keyring) {
/* always install a session keyring upon access if one
* doesn't exist yet */
- ret = install_user_keyrings(context);
+ 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;
+ goto reget_creds;
}
rcu_read_lock();
- key = rcu_dereference(context->signal->session_keyring);
+ key = rcu_dereference(cred->tgcred->session_keyring);
atomic_inc(&key->usage);
rcu_read_unlock();
key_ref = make_key_ref(key, 1);
break;
case KEY_SPEC_USER_KEYRING:
- if (!context->user->uid_keyring) {
- ret = install_user_keyrings(context);
+ if (!cred->user->uid_keyring) {
+ ret = install_user_keyrings();
if (ret < 0)
goto error;
}
- key = context->user->uid_keyring;
+ key = cred->user->uid_keyring;
atomic_inc(&key->usage);
key_ref = make_key_ref(key, 1);
break;
case KEY_SPEC_USER_SESSION_KEYRING:
- if (!context->user->session_keyring) {
- ret = install_user_keyrings(context);
+ if (!cred->user->session_keyring) {
+ ret = install_user_keyrings();
if (ret < 0)
goto error;
}
- key = context->user->session_keyring;
+ key = cred->user->session_keyring;
atomic_inc(&key->usage);
key_ref = make_key_ref(key, 1);
break;
@@ -669,7 +587,7 @@ key_ref_t lookup_user_key(struct task_struct *context, key_serial_t id,
goto error;
case KEY_SPEC_REQKEY_AUTH_KEY:
- key = context->request_key_auth;
+ key = cred->request_key_auth;
if (!key)
goto error;
@@ -677,6 +595,25 @@ key_ref_t lookup_user_key(struct task_struct *context, key_serial_t id,
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)
@@ -693,7 +630,7 @@ key_ref_t lookup_user_key(struct task_struct *context, key_serial_t id,
/* check to see if we possess the key */
skey_ref = search_process_keyrings(key->type, key,
lookup_user_key_possessed,
- current);
+ cred);
if (!IS_ERR(skey_ref)) {
key_put(key);
@@ -725,11 +662,12 @@ key_ref_t lookup_user_key(struct task_struct *context, key_serial_t id,
goto invalid_key;
/* check the permissions */
- ret = key_task_permission(key_ref, context, perm);
+ ret = key_task_permission(key_ref, cred, perm);
if (ret < 0)
goto invalid_key;
error:
+ put_cred(cred);
return key_ref;
invalid_key:
@@ -737,6 +675,12 @@ invalid_key:
key_ref = ERR_PTR(ret);
goto error;
+ /* if we attempted to install a keyring, then it may have caused new
+ * creds to be installed */
+reget_creds:
+ put_cred(cred);
+ goto try_again;
+
} /* end lookup_user_key() */
/*****************************************************************************/
@@ -748,20 +692,33 @@ invalid_key:
*/
long join_session_keyring(const char *name)
{
- struct task_struct *tsk = current;
+ const struct cred *old;
+ struct cred *new;
struct key *keyring;
- long ret;
+ long ret, serial;
+
+ /* only permit this if there's a single thread in the thread group -
+ * this avoids us having to adjust the creds on all threads and risking
+ * ENOMEM */
+ if (!is_single_threaded(current))
+ return -EMLINK;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
/* if no name is provided, install an anonymous keyring */
if (!name) {
- ret = install_session_keyring(tsk, NULL);
+ ret = install_session_keyring_to_cred(new, NULL);
if (ret < 0)
goto error;
- rcu_read_lock();
- ret = rcu_dereference(tsk->signal->session_keyring)->serial;
- rcu_read_unlock();
- goto error;
+ serial = new->tgcred->session_keyring->serial;
+ ret = commit_creds(new);
+ if (ret == 0)
+ ret = serial;
+ goto okay;
}
/* allow the user to join or create a named keyring */
@@ -771,29 +728,33 @@ long join_session_keyring(const char *name)
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, old->uid, old->gid, old,
KEY_ALLOC_IN_QUOTA, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error2;
}
- }
- else if (IS_ERR(keyring)) {
+ } else if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error2;
}
/* we've got a keyring - now to install it */
- ret = install_session_keyring(tsk, keyring);
+ ret = install_session_keyring_to_cred(new, keyring);
if (ret < 0)
goto error2;
+ commit_creds(new);
+ mutex_unlock(&key_session_mutex);
+
ret = keyring->serial;
key_put(keyring);
+okay:
+ return ret;
error2:
mutex_unlock(&key_session_mutex);
error:
+ abort_creds(new);
return ret;
-
-} /* end join_session_keyring() */
+}
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index abea08f87fe2..0e04f72ef2d4 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -19,6 +19,8 @@
#include <linux/slab.h>
#include "internal.h"
+#define key_negative_timeout 60 /* default timeout on a negative key's existence */
+
/*
* wait_on_bit() sleep function for uninterruptible waiting
*/
@@ -64,7 +66,7 @@ static int call_sbin_request_key(struct key_construction *cons,
const char *op,
void *aux)
{
- struct task_struct *tsk = current;
+ const struct cred *cred = current_cred();
key_serial_t prkey, sskey;
struct key *key = cons->key, *authkey = cons->authkey, *keyring;
char *argv[9], *envp[3], uid_str[12], gid_str[12];
@@ -74,15 +76,17 @@ static int call_sbin_request_key(struct key_construction *cons,
kenter("{%d},{%d},%s", key->serial, authkey->serial, op);
- ret = install_user_keyrings(tsk);
+ ret = install_user_keyrings();
if (ret < 0)
goto error_alloc;
/* allocate a new session keyring */
sprintf(desc, "_req.%u", key->serial);
- keyring = keyring_alloc(desc, current->fsuid, current->fsgid, current,
+ cred = get_current_cred();
+ keyring = keyring_alloc(desc, cred->fsuid, cred->fsgid, cred,
KEY_ALLOC_QUOTA_OVERRUN, NULL);
+ put_cred(cred);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error_alloc;
@@ -94,29 +98,24 @@ static int call_sbin_request_key(struct key_construction *cons,
goto error_link;
/* record the UID and GID */
- sprintf(uid_str, "%d", current->fsuid);
- sprintf(gid_str, "%d", current->fsgid);
+ sprintf(uid_str, "%d", cred->fsuid);
+ sprintf(gid_str, "%d", cred->fsgid);
/* we say which key is under construction */
sprintf(key_str, "%d", key->serial);
/* we specify the process's default keyrings */
sprintf(keyring_str[0], "%d",
- tsk->thread_keyring ? tsk->thread_keyring->serial : 0);
+ cred->thread_keyring ? cred->thread_keyring->serial : 0);
prkey = 0;
- if (tsk->signal->process_keyring)
- prkey = tsk->signal->process_keyring->serial;
-
- sprintf(keyring_str[1], "%d", prkey);
+ if (cred->tgcred->process_keyring)
+ prkey = cred->tgcred->process_keyring->serial;
- if (tsk->signal->session_keyring) {
- rcu_read_lock();
- sskey = rcu_dereference(tsk->signal->session_keyring)->serial;
- rcu_read_unlock();
- } else {
- sskey = tsk->user->session_keyring->serial;
- }
+ if (cred->tgcred->session_keyring)
+ sskey = rcu_dereference(cred->tgcred->session_keyring)->serial;
+ else
+ sskey = cred->user->session_keyring->serial;
sprintf(keyring_str[2], "%d", sskey);
@@ -157,8 +156,8 @@ error_link:
key_put(keyring);
error_alloc:
- kleave(" = %d", ret);
complete_request_key(cons, ret);
+ kleave(" = %d", ret);
return ret;
}
@@ -167,7 +166,8 @@ error_alloc:
* - we ignore program failure and go on key status instead
*/
static int construct_key(struct key *key, const void *callout_info,
- size_t callout_len, void *aux)
+ size_t callout_len, void *aux,
+ struct key *dest_keyring)
{
struct key_construction *cons;
request_key_actor_t actor;
@@ -181,7 +181,8 @@ static int construct_key(struct key *key, const void *callout_info,
return -ENOMEM;
/* allocate an authorisation key */
- authkey = request_key_auth_new(key, callout_info, callout_len);
+ authkey = request_key_auth_new(key, callout_info, callout_len,
+ dest_keyring);
if (IS_ERR(authkey)) {
kfree(cons);
ret = PTR_ERR(authkey);
@@ -209,46 +210,67 @@ static int construct_key(struct key *key, const void *callout_info,
}
/*
- * link a key to the appropriate destination keyring
- * - the caller must hold a write lock on the destination keyring
+ * get the appropriate destination keyring for the request
+ * - we return whatever keyring we select with an extra reference upon it which
+ * the caller must release
*/
-static void construct_key_make_link(struct key *key, struct key *dest_keyring)
+static void construct_get_dest_keyring(struct key **_dest_keyring)
{
- struct task_struct *tsk = current;
- struct key *drop = NULL;
+ struct request_key_auth *rka;
+ const struct cred *cred = current_cred();
+ struct key *dest_keyring = *_dest_keyring, *authkey;
- kenter("{%d},%p", key->serial, dest_keyring);
+ kenter("%p", dest_keyring);
/* find the appropriate keyring */
- if (!dest_keyring) {
- switch (tsk->jit_keyring) {
+ if (dest_keyring) {
+ /* the caller supplied one */
+ key_get(dest_keyring);
+ } else {
+ /* use a default keyring; falling through the cases until we
+ * find one that we actually have */
+ switch (cred->jit_keyring) {
case KEY_REQKEY_DEFL_DEFAULT:
+ case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
+ if (cred->request_key_auth) {
+ authkey = cred->request_key_auth;
+ down_read(&authkey->sem);
+ rka = authkey->payload.data;
+ if (!test_bit(KEY_FLAG_REVOKED,
+ &authkey->flags))
+ dest_keyring =
+ key_get(rka->dest_keyring);
+ up_read(&authkey->sem);
+ if (dest_keyring)
+ break;
+ }
+
case KEY_REQKEY_DEFL_THREAD_KEYRING:
- dest_keyring = tsk->thread_keyring;
+ dest_keyring = key_get(cred->thread_keyring);
if (dest_keyring)
break;
case KEY_REQKEY_DEFL_PROCESS_KEYRING:
- dest_keyring = tsk->signal->process_keyring;
+ dest_keyring = key_get(cred->tgcred->process_keyring);
if (dest_keyring)
break;
case KEY_REQKEY_DEFL_SESSION_KEYRING:
rcu_read_lock();
dest_keyring = key_get(
- rcu_dereference(tsk->signal->session_keyring));
+ rcu_dereference(cred->tgcred->session_keyring));
rcu_read_unlock();
- drop = dest_keyring;
if (dest_keyring)
break;
case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
- dest_keyring = tsk->user->session_keyring;
+ dest_keyring =
+ key_get(cred->user->session_keyring);
break;
case KEY_REQKEY_DEFL_USER_KEYRING:
- dest_keyring = tsk->user->uid_keyring;
+ dest_keyring = key_get(cred->user->uid_keyring);
break;
case KEY_REQKEY_DEFL_GROUP_KEYRING:
@@ -257,10 +279,9 @@ static void construct_key_make_link(struct key *key, struct key *dest_keyring)
}
}
- /* and attach the key to it */
- __key_link(dest_keyring, key);
- key_put(drop);
- kleave("");
+ *_dest_keyring = dest_keyring;
+ kleave(" [dk %d]", key_serial(dest_keyring));
+ return;
}
/*
@@ -275,6 +296,7 @@ static int construct_alloc_key(struct key_type *type,
struct key_user *user,
struct key **_key)
{
+ const struct cred *cred = current_cred();
struct key *key;
key_ref_t key_ref;
@@ -282,33 +304,28 @@ static int construct_alloc_key(struct key_type *type,
mutex_lock(&user->cons_lock);
- key = key_alloc(type, description,
- current->fsuid, current->fsgid, current, KEY_POS_ALL,
- flags);
+ key = key_alloc(type, description, cred->fsuid, cred->fsgid, cred,
+ KEY_POS_ALL, flags);
if (IS_ERR(key))
goto alloc_failed;
set_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags);
- if (dest_keyring)
- down_write(&dest_keyring->sem);
+ down_write(&dest_keyring->sem);
/* attach the key to the destination keyring under lock, but we do need
* to do another check just in case someone beat us to it whilst we
* waited for locks */
mutex_lock(&key_construction_mutex);
- key_ref = search_process_keyrings(type, description, type->match,
- current);
+ key_ref = search_process_keyrings(type, description, type->match, cred);
if (!IS_ERR(key_ref))
goto key_already_present;
- if (dest_keyring)
- construct_key_make_link(key, dest_keyring);
+ __key_link(dest_keyring, key);
mutex_unlock(&key_construction_mutex);
- if (dest_keyring)
- up_write(&dest_keyring->sem);
+ up_write(&dest_keyring->sem);
mutex_unlock(&user->cons_lock);
*_key = key;
kleave(" = 0 [%d]", key_serial(key));
@@ -346,25 +363,36 @@ static struct key *construct_key_and_link(struct key_type *type,
struct key *key;
int ret;
- user = key_user_lookup(current->fsuid);
+ kenter("");
+
+ user = key_user_lookup(current_fsuid());
if (!user)
return ERR_PTR(-ENOMEM);
+ construct_get_dest_keyring(&dest_keyring);
+
ret = construct_alloc_key(type, description, dest_keyring, flags, user,
&key);
key_user_put(user);
if (ret == 0) {
- ret = construct_key(key, callout_info, callout_len, aux);
- if (ret < 0)
+ ret = construct_key(key, callout_info, callout_len, aux,
+ dest_keyring);
+ if (ret < 0) {
+ kdebug("cons failed");
goto construction_failed;
+ }
}
+ key_put(dest_keyring);
+ kleave(" = key %d", key_serial(key));
return key;
construction_failed:
key_negate_and_link(key, key_negative_timeout, NULL, NULL);
key_put(key);
+ key_put(dest_keyring);
+ kleave(" = %d", ret);
return ERR_PTR(ret);
}
@@ -383,6 +411,7 @@ struct key *request_key_and_link(struct key_type *type,
struct key *dest_keyring,
unsigned long flags)
{
+ const struct cred *cred = current_cred();
struct key *key;
key_ref_t key_ref;
@@ -392,7 +421,7 @@ struct key *request_key_and_link(struct key_type *type,
/* search all the process keyrings for a key */
key_ref = search_process_keyrings(type, description, type->match,
- current);
+ cred);
if (!IS_ERR(key_ref)) {
key = key_ref_to_ptr(key_ref);
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index bd237b0a6331..86747151ee5b 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -105,9 +105,9 @@ static void request_key_auth_revoke(struct key *key)
kenter("{%d}", key->serial);
- if (rka->context) {
- put_task_struct(rka->context);
- rka->context = NULL;
+ if (rka->cred) {
+ put_cred(rka->cred);
+ rka->cred = NULL;
}
} /* end request_key_auth_revoke() */
@@ -122,12 +122,13 @@ static void request_key_auth_destroy(struct key *key)
kenter("{%d}", key->serial);
- if (rka->context) {
- put_task_struct(rka->context);
- rka->context = NULL;
+ if (rka->cred) {
+ put_cred(rka->cred);
+ rka->cred = NULL;
}
key_put(rka->target_key);
+ key_put(rka->dest_keyring);
kfree(rka->callout_info);
kfree(rka);
@@ -139,9 +140,10 @@ static void request_key_auth_destroy(struct key *key)
* access to the caller's security data
*/
struct key *request_key_auth_new(struct key *target, const void *callout_info,
- size_t callout_len)
+ size_t callout_len, struct key *dest_keyring)
{
struct request_key_auth *rka, *irka;
+ const struct cred *cred = current->cred;
struct key *authkey = NULL;
char desc[20];
int ret;
@@ -163,31 +165,29 @@ struct key *request_key_auth_new(struct key *target, const void *callout_info,
/* see if the calling process is already servicing the key request of
* another process */
- if (current->request_key_auth) {
+ if (cred->request_key_auth) {
/* it is - use that instantiation context here too */
- down_read(&current->request_key_auth->sem);
+ down_read(&cred->request_key_auth->sem);
/* if the auth key has been revoked, then the key we're
* servicing is already instantiated */
- if (test_bit(KEY_FLAG_REVOKED,
- &current->request_key_auth->flags))
+ if (test_bit(KEY_FLAG_REVOKED, &cred->request_key_auth->flags))
goto auth_key_revoked;
- irka = current->request_key_auth->payload.data;
- rka->context = irka->context;
+ irka = cred->request_key_auth->payload.data;
+ rka->cred = get_cred(irka->cred);
rka->pid = irka->pid;
- get_task_struct(rka->context);
- up_read(&current->request_key_auth->sem);
+ up_read(&cred->request_key_auth->sem);
}
else {
/* it isn't - use this process as the context */
- rka->context = current;
+ rka->cred = get_cred(cred);
rka->pid = current->pid;
- get_task_struct(rka->context);
}
rka->target_key = key_get(target);
+ rka->dest_keyring = key_get(dest_keyring);
memcpy(rka->callout_info, callout_info, callout_len);
rka->callout_len = callout_len;
@@ -195,7 +195,7 @@ struct key *request_key_auth_new(struct key *target, const void *callout_info,
sprintf(desc, "%x", target->serial);
authkey = key_alloc(&key_type_request_key_auth, desc,
- current->fsuid, current->fsgid, current,
+ cred->fsuid, cred->fsgid, cred,
KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH |
KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA);
if (IS_ERR(authkey)) {
@@ -203,16 +203,16 @@ struct key *request_key_auth_new(struct key *target, const void *callout_info,
goto error_alloc;
}
- /* construct and attach to the keyring */
+ /* construct the auth key */
ret = key_instantiate_and_link(authkey, rka, 0, NULL, NULL);
if (ret < 0)
goto error_inst;
- kleave(" = {%d}", authkey->serial);
+ kleave(" = {%d,%d}", authkey->serial, atomic_read(&authkey->usage));
return authkey;
auth_key_revoked:
- up_read(&current->request_key_auth->sem);
+ up_read(&cred->request_key_auth->sem);
kfree(rka->callout_info);
kfree(rka);
kleave("= -EKEYREVOKED");
@@ -223,6 +223,7 @@ error_inst:
key_put(authkey);
error_alloc:
key_put(rka->target_key);
+ key_put(rka->dest_keyring);
kfree(rka->callout_info);
kfree(rka);
kleave("= %d", ret);
@@ -254,6 +255,7 @@ static int key_get_instantiation_authkey_match(const struct key *key,
*/
struct key *key_get_instantiation_authkey(key_serial_t target_id)
{
+ const struct cred *cred = current_cred();
struct key *authkey;
key_ref_t authkey_ref;
@@ -261,7 +263,7 @@ struct key *key_get_instantiation_authkey(key_serial_t target_id)
&key_type_request_key_auth,
(void *) (unsigned long) target_id,
key_get_instantiation_authkey_match,
- current);
+ cred);
if (IS_ERR(authkey_ref)) {
authkey = ERR_CAST(authkey_ref);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.