Thomas Gleixner | 2874c5f | 2019-05-27 08:55:01 +0200 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 2 | /* Manage a process's keyrings |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 4 | * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * Written by David Howells (dhowells@redhat.com) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | */ |
| 7 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | #include <linux/init.h> |
| 9 | #include <linux/sched.h> |
Ingo Molnar | 8703e8a | 2017-02-08 18:51:30 +0100 | [diff] [blame] | 10 | #include <linux/sched/user.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/keyctl.h> |
| 12 | #include <linux/fs.h> |
| 13 | #include <linux/err.h> |
Ingo Molnar | bb003079 | 2006-03-22 00:09:14 -0800 | [diff] [blame] | 14 | #include <linux/mutex.h> |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 15 | #include <linux/security.h> |
Serge E. Hallyn | 1d1e975 | 2009-02-26 18:27:38 -0600 | [diff] [blame] | 16 | #include <linux/user_namespace.h> |
Linus Torvalds | 7c0f6ba | 2016-12-24 11:46:01 -0800 | [diff] [blame] | 17 | #include <linux/uaccess.h> |
David Howells | 822ad64 | 2019-02-14 16:20:25 +0000 | [diff] [blame] | 18 | #include <keys/request_key_auth-type.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include "internal.h" |
| 20 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 21 | /* Session keyring create vs join semaphore */ |
Ingo Molnar | bb003079 | 2006-03-22 00:09:14 -0800 | [diff] [blame] | 22 | static DEFINE_MUTEX(key_session_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 24 | /* User keyring creation semaphore */ |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 25 | static DEFINE_MUTEX(key_user_keyring_mutex); |
| 26 | |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 27 | /* The root user's tracking struct */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | struct key_user root_key_user = { |
Elena Reshetova | ddb99e1 | 2017-03-31 15:20:49 +0300 | [diff] [blame] | 29 | .usage = REFCOUNT_INIT(3), |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 30 | .cons_lock = __MUTEX_INITIALIZER(root_key_user.cons_lock), |
Peter Zijlstra | 6cfd76a | 2006-12-06 20:37:22 -0800 | [diff] [blame] | 31 | .lock = __SPIN_LOCK_UNLOCKED(root_key_user.lock), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | .nkeys = ATOMIC_INIT(2), |
| 33 | .nikeys = ATOMIC_INIT(2), |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 34 | .uid = GLOBAL_ROOT_UID, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | }; |
| 36 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 38 | * Install the user and user session keyrings for the current process's UID. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | */ |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 40 | int install_user_keyrings(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 42 | struct user_struct *user; |
| 43 | const struct cred *cred; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | struct key *uid_keyring, *session_keyring; |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 45 | key_perm_t user_keyring_perm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | char buf[20]; |
| 47 | int ret; |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 48 | uid_t uid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 50 | user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 51 | cred = current_cred(); |
| 52 | user = cred->user; |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 53 | uid = from_kuid(cred->user_ns, user->uid); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 54 | |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 55 | kenter("%p{%u}", user, uid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 57 | if (READ_ONCE(user->uid_keyring) && READ_ONCE(user->session_keyring)) { |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 58 | kleave(" = 0 [exist]"); |
| 59 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | } |
| 61 | |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 62 | mutex_lock(&key_user_keyring_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | ret = 0; |
| 64 | |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 65 | if (!user->uid_keyring) { |
| 66 | /* get the UID-specific keyring |
| 67 | * - there may be one in existence already as it may have been |
| 68 | * pinned by a session, but the user_struct pointing to it |
| 69 | * may have been destroyed by setuid */ |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 70 | sprintf(buf, "_uid.%u", uid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 72 | uid_keyring = find_keyring_by_name(buf, true); |
| 73 | if (IS_ERR(uid_keyring)) { |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 74 | uid_keyring = keyring_alloc(buf, user->uid, INVALID_GID, |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 75 | cred, user_keyring_perm, |
Eric Biggers | 237bbd2 | 2017-09-18 11:37:03 -0700 | [diff] [blame] | 76 | KEY_ALLOC_UID_KEYRING | |
| 77 | KEY_ALLOC_IN_QUOTA, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 78 | NULL, NULL); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 79 | if (IS_ERR(uid_keyring)) { |
| 80 | ret = PTR_ERR(uid_keyring); |
| 81 | goto error; |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | /* get a default session keyring (which might also exist |
| 86 | * already) */ |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 87 | sprintf(buf, "_uid_ses.%u", uid); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 88 | |
| 89 | session_keyring = find_keyring_by_name(buf, true); |
| 90 | if (IS_ERR(session_keyring)) { |
| 91 | session_keyring = |
Eric W. Biederman | 9a56c2d | 2012-02-08 07:53:04 -0800 | [diff] [blame] | 92 | keyring_alloc(buf, user->uid, INVALID_GID, |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 93 | cred, user_keyring_perm, |
Eric Biggers | 237bbd2 | 2017-09-18 11:37:03 -0700 | [diff] [blame] | 94 | KEY_ALLOC_UID_KEYRING | |
| 95 | KEY_ALLOC_IN_QUOTA, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 96 | NULL, NULL); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 97 | if (IS_ERR(session_keyring)) { |
| 98 | ret = PTR_ERR(session_keyring); |
| 99 | goto error_release; |
| 100 | } |
| 101 | |
| 102 | /* we install a link from the user session keyring to |
| 103 | * the user keyring */ |
| 104 | ret = key_link(session_keyring, uid_keyring); |
| 105 | if (ret < 0) |
| 106 | goto error_release_both; |
| 107 | } |
| 108 | |
| 109 | /* install the keyrings */ |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 110 | /* paired with READ_ONCE() */ |
| 111 | smp_store_release(&user->uid_keyring, uid_keyring); |
| 112 | /* paired with READ_ONCE() */ |
| 113 | smp_store_release(&user->session_keyring, session_keyring); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 114 | } |
| 115 | |
| 116 | mutex_unlock(&key_user_keyring_mutex); |
| 117 | kleave(" = 0"); |
| 118 | return 0; |
| 119 | |
| 120 | error_release_both: |
| 121 | key_put(session_keyring); |
| 122 | error_release: |
| 123 | key_put(uid_keyring); |
| 124 | error: |
| 125 | mutex_unlock(&key_user_keyring_mutex); |
| 126 | kleave(" = %d", ret); |
| 127 | return ret; |
| 128 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | /* |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 131 | * Install a thread keyring to the given credentials struct if it didn't have |
| 132 | * one already. This is allowed to overrun the quota. |
| 133 | * |
| 134 | * Return: 0 if a thread keyring is now present; -errno on failure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 136 | int install_thread_keyring_to_cred(struct cred *new) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 138 | struct key *keyring; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 140 | if (new->thread_keyring) |
| 141 | return 0; |
| 142 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 143 | keyring = keyring_alloc("_tid", new->uid, new->gid, new, |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 144 | KEY_POS_ALL | KEY_USR_VIEW, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 145 | KEY_ALLOC_QUOTA_OVERRUN, |
| 146 | NULL, NULL); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 147 | if (IS_ERR(keyring)) |
| 148 | return PTR_ERR(keyring); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 150 | new->thread_keyring = keyring; |
| 151 | return 0; |
| 152 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | /* |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 155 | * Install a thread keyring to the current task if it didn't have one already. |
| 156 | * |
| 157 | * Return: 0 if a thread keyring is now present; -errno on failure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 159 | static int install_thread_keyring(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 161 | struct cred *new; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | int ret; |
| 163 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 164 | new = prepare_creds(); |
| 165 | if (!new) |
| 166 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 168 | ret = install_thread_keyring_to_cred(new); |
| 169 | if (ret < 0) { |
| 170 | abort_creds(new); |
| 171 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | } |
| 173 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 174 | return commit_creds(new); |
| 175 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 177 | /* |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 178 | * Install a process keyring to the given credentials struct if it didn't have |
| 179 | * one already. This is allowed to overrun the quota. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 180 | * |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 181 | * Return: 0 if a process keyring is now present; -errno on failure. |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 182 | */ |
| 183 | int install_process_keyring_to_cred(struct cred *new) |
| 184 | { |
| 185 | struct key *keyring; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 187 | if (new->process_keyring) |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 188 | return 0; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 189 | |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 190 | keyring = keyring_alloc("_pid", new->uid, new->gid, new, |
| 191 | KEY_POS_ALL | KEY_USR_VIEW, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 192 | KEY_ALLOC_QUOTA_OVERRUN, |
| 193 | NULL, NULL); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 194 | if (IS_ERR(keyring)) |
| 195 | return PTR_ERR(keyring); |
| 196 | |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 197 | new->process_keyring = keyring; |
| 198 | return 0; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 199 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | /* |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 202 | * Install a process keyring to the current task if it didn't have one already. |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 203 | * |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 204 | * Return: 0 if a process keyring is now present; -errno on failure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 206 | static int install_process_keyring(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 208 | struct cred *new; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | int ret; |
| 210 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 211 | new = prepare_creds(); |
| 212 | if (!new) |
| 213 | return -ENOMEM; |
David Howells | 1a26feb | 2006-04-10 22:54:26 -0700 | [diff] [blame] | 214 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 215 | ret = install_process_keyring_to_cred(new); |
| 216 | if (ret < 0) { |
| 217 | abort_creds(new); |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 218 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | } |
| 220 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 221 | return commit_creds(new); |
| 222 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | /* |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 225 | * Install the given keyring as the session keyring of the given credentials |
| 226 | * struct, replacing the existing one if any. If the given keyring is NULL, |
| 227 | * then install a new anonymous session keyring. |
Jann Horn | 5c7e372 | 2019-03-27 16:39:38 +0100 | [diff] [blame] | 228 | * @cred can not be in use by any task yet. |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 229 | * |
| 230 | * Return: 0 on success; -errno on failure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | */ |
Oleg Nesterov | 685bfd2 | 2010-05-26 14:43:00 -0700 | [diff] [blame] | 232 | int install_session_keyring_to_cred(struct cred *cred, struct key *keyring) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | { |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 234 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | struct key *old; |
David Howells | 1a26feb | 2006-04-10 22:54:26 -0700 | [diff] [blame] | 236 | |
| 237 | might_sleep(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | |
| 239 | /* create an empty session keyring */ |
| 240 | if (!keyring) { |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 241 | flags = KEY_ALLOC_QUOTA_OVERRUN; |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 242 | if (cred->session_keyring) |
David Howells | 7e047ef | 2006-06-26 00:24:50 -0700 | [diff] [blame] | 243 | flags = KEY_ALLOC_IN_QUOTA; |
| 244 | |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 245 | keyring = keyring_alloc("_ses", cred->uid, cred->gid, cred, |
| 246 | KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 247 | flags, NULL, NULL); |
David Howells | 1a26feb | 2006-04-10 22:54:26 -0700 | [diff] [blame] | 248 | if (IS_ERR(keyring)) |
| 249 | return PTR_ERR(keyring); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 250 | } else { |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 251 | __key_get(keyring); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | } |
| 253 | |
| 254 | /* install the keyring */ |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 255 | old = cred->session_keyring; |
Jann Horn | 5c7e372 | 2019-03-27 16:39:38 +0100 | [diff] [blame] | 256 | cred->session_keyring = keyring; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 257 | |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 258 | if (old) |
David Howells | 1a26feb | 2006-04-10 22:54:26 -0700 | [diff] [blame] | 259 | key_put(old); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | |
David Howells | 1a26feb | 2006-04-10 22:54:26 -0700 | [diff] [blame] | 261 | return 0; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 262 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | /* |
Eric Biggers | c9f838d | 2017-04-18 15:31:09 +0100 | [diff] [blame] | 265 | * Install the given keyring as the session keyring of the current task, |
| 266 | * replacing the existing one if any. If the given keyring is NULL, then |
| 267 | * install a new anonymous session keyring. |
| 268 | * |
| 269 | * Return: 0 on success; -errno on failure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 271 | static int install_session_keyring(struct key *keyring) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 273 | struct cred *new; |
| 274 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 276 | new = prepare_creds(); |
| 277 | if (!new) |
| 278 | return -ENOMEM; |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 279 | |
David Howells | 99599537 | 2011-08-22 14:08:33 +0100 | [diff] [blame] | 280 | ret = install_session_keyring_to_cred(new, keyring); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 281 | if (ret < 0) { |
| 282 | abort_creds(new); |
| 283 | return ret; |
| 284 | } |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 285 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 286 | return commit_creds(new); |
| 287 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 290 | * Handle the fsuid changing. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | */ |
| 292 | void key_fsuid_changed(struct task_struct *tsk) |
| 293 | { |
| 294 | /* update the ownership of the thread keyring */ |
David Howells | b6dff3e | 2008-11-14 10:39:16 +1100 | [diff] [blame] | 295 | BUG_ON(!tsk->cred); |
| 296 | if (tsk->cred->thread_keyring) { |
| 297 | down_write(&tsk->cred->thread_keyring->sem); |
| 298 | tsk->cred->thread_keyring->uid = tsk->cred->fsuid; |
| 299 | up_write(&tsk->cred->thread_keyring->sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 301 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 304 | * Handle the fsgid changing. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | */ |
| 306 | void key_fsgid_changed(struct task_struct *tsk) |
| 307 | { |
| 308 | /* update the ownership of the thread keyring */ |
David Howells | b6dff3e | 2008-11-14 10:39:16 +1100 | [diff] [blame] | 309 | BUG_ON(!tsk->cred); |
| 310 | if (tsk->cred->thread_keyring) { |
| 311 | down_write(&tsk->cred->thread_keyring->sem); |
| 312 | tsk->cred->thread_keyring->gid = tsk->cred->fsgid; |
| 313 | up_write(&tsk->cred->thread_keyring->sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | } |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 315 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 318 | * Search the process keyrings attached to the supplied cred for the first |
| 319 | * matching key. |
| 320 | * |
| 321 | * The search criteria are the type and the match function. The description is |
| 322 | * given to the match function as a parameter, but doesn't otherwise influence |
| 323 | * the search. Typically the match function will compare the description |
| 324 | * parameter to the key's description. |
| 325 | * |
| 326 | * This can only search keyrings that grant Search permission to the supplied |
| 327 | * credentials. Keyrings linked to searched keyrings will also be searched if |
| 328 | * they grant Search permission too. Keys can only be found if they grant |
| 329 | * Search permission to the credentials. |
| 330 | * |
| 331 | * Returns a pointer to the key with the key usage count incremented if |
| 332 | * successful, -EAGAIN if we didn't find any matching key or -ENOKEY if we only |
| 333 | * matched negative keys. |
| 334 | * |
| 335 | * In the case of a successful return, the possession attribute is set on the |
| 336 | * returned key reference. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | */ |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 338 | key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | { |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 340 | key_ref_t key_ref, ret, err; |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 341 | const struct cred *cred = ctx->cred; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | |
| 343 | /* we want to return -EAGAIN or -ENOKEY if any of the keyrings were |
| 344 | * searchable, but we failed to find a key or we found a negative key; |
| 345 | * otherwise we want to return a sample error (probably -EACCES) if |
| 346 | * none of the keyrings were searchable |
| 347 | * |
| 348 | * in terms of priority: success > -ENOKEY > -EAGAIN > other error |
| 349 | */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 350 | key_ref = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | ret = NULL; |
| 352 | err = ERR_PTR(-EAGAIN); |
| 353 | |
| 354 | /* search the thread keyring first */ |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 355 | if (cred->thread_keyring) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 356 | key_ref = keyring_search_aux( |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 357 | make_key_ref(cred->thread_keyring, 1), ctx); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 358 | if (!IS_ERR(key_ref)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 359 | goto found; |
| 360 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 361 | switch (PTR_ERR(key_ref)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | case -EAGAIN: /* no key */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | case -ENOKEY: /* negative key */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 364 | ret = key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | break; |
| 366 | default: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 367 | err = key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | break; |
| 369 | } |
| 370 | } |
| 371 | |
| 372 | /* search the process keyring second */ |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 373 | if (cred->process_keyring) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 374 | key_ref = keyring_search_aux( |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 375 | make_key_ref(cred->process_keyring, 1), ctx); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 376 | if (!IS_ERR(key_ref)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | goto found; |
| 378 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 379 | switch (PTR_ERR(key_ref)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 380 | case -EAGAIN: /* no key */ |
David Howells | fe9453a | 2013-02-21 12:00:25 +0000 | [diff] [blame] | 381 | if (ret) |
| 382 | break; |
Mathieu Malaterre | 0f949bc | 2019-01-14 21:17:24 +0100 | [diff] [blame] | 383 | /* fall through */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | case -ENOKEY: /* negative key */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 385 | ret = key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | break; |
| 387 | default: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 388 | err = key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | break; |
| 390 | } |
| 391 | } |
| 392 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 393 | /* search the session keyring */ |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 394 | if (cred->session_keyring) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 395 | key_ref = keyring_search_aux( |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 396 | make_key_ref(cred->session_keyring, 1), ctx); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 398 | if (!IS_ERR(key_ref)) |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 399 | goto found; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 401 | switch (PTR_ERR(key_ref)) { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 402 | case -EAGAIN: /* no key */ |
| 403 | if (ret) |
| 404 | break; |
Mathieu Malaterre | 0f949bc | 2019-01-14 21:17:24 +0100 | [diff] [blame] | 405 | /* fall through */ |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 406 | case -ENOKEY: /* negative key */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 407 | ret = key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 408 | break; |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 409 | default: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 410 | err = key_ref; |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 411 | break; |
| 412 | } |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 413 | } |
| 414 | /* or search the user-session keyring */ |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 415 | else if (READ_ONCE(cred->user->session_keyring)) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 416 | key_ref = keyring_search_aux( |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 417 | make_key_ref(READ_ONCE(cred->user->session_keyring), 1), |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 418 | ctx); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 419 | if (!IS_ERR(key_ref)) |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 420 | goto found; |
| 421 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 422 | switch (PTR_ERR(key_ref)) { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 423 | case -EAGAIN: /* no key */ |
| 424 | if (ret) |
| 425 | break; |
Mathieu Malaterre | 0f949bc | 2019-01-14 21:17:24 +0100 | [diff] [blame] | 426 | /* fall through */ |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 427 | case -ENOKEY: /* negative key */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 428 | ret = key_ref; |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 429 | break; |
| 430 | default: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 431 | err = key_ref; |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 432 | break; |
| 433 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | } |
| 435 | |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 436 | /* no key - decide on the error we're going to go for */ |
| 437 | key_ref = ret ? ret : err; |
| 438 | |
| 439 | found: |
| 440 | return key_ref; |
| 441 | } |
| 442 | |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 443 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 444 | * Search the process keyrings attached to the supplied cred for the first |
| 445 | * matching key in the manner of search_my_process_keyrings(), but also search |
| 446 | * the keys attached to the assumed authorisation key using its credentials if |
| 447 | * one is available. |
| 448 | * |
| 449 | * Return same as search_my_process_keyrings(). |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 450 | */ |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 451 | key_ref_t search_process_keyrings(struct keyring_search_context *ctx) |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 452 | { |
| 453 | struct request_key_auth *rka; |
| 454 | key_ref_t key_ref, ret = ERR_PTR(-EACCES), err; |
| 455 | |
| 456 | might_sleep(); |
| 457 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 458 | key_ref = search_my_process_keyrings(ctx); |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 459 | if (!IS_ERR(key_ref)) |
| 460 | goto found; |
| 461 | err = key_ref; |
| 462 | |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 463 | /* if this process has an instantiation authorisation key, then we also |
| 464 | * search the keyrings of the process mentioned there |
| 465 | * - we don't permit access to request_key auth keys via this method |
| 466 | */ |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 467 | if (ctx->cred->request_key_auth && |
| 468 | ctx->cred == current_cred() && |
| 469 | ctx->index_key.type != &key_type_request_key_auth |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 470 | ) { |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 471 | const struct cred *cred = ctx->cred; |
| 472 | |
David Howells | 04c567d | 2006-06-22 14:47:18 -0700 | [diff] [blame] | 473 | /* defend against the auth key being revoked */ |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 474 | down_read(&cred->request_key_auth->sem); |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 475 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 476 | if (key_validate(ctx->cred->request_key_auth) == 0) { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 477 | rka = ctx->cred->request_key_auth->payload.data[0]; |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 478 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 479 | ctx->cred = rka->cred; |
| 480 | key_ref = search_process_keyrings(ctx); |
| 481 | ctx->cred = cred; |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 482 | |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 483 | up_read(&cred->request_key_auth->sem); |
David Howells | 04c567d | 2006-06-22 14:47:18 -0700 | [diff] [blame] | 484 | |
| 485 | if (!IS_ERR(key_ref)) |
| 486 | goto found; |
| 487 | |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 488 | ret = key_ref; |
David Howells | 04c567d | 2006-06-22 14:47:18 -0700 | [diff] [blame] | 489 | } else { |
David Howells | c69e8d9 | 2008-11-14 10:39:19 +1100 | [diff] [blame] | 490 | up_read(&cred->request_key_auth->sem); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 491 | } |
| 492 | } |
| 493 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | /* no key - decide on the error we're going to go for */ |
David Howells | 927942a | 2010-06-11 17:31:10 +0100 | [diff] [blame] | 495 | if (err == ERR_PTR(-ENOKEY) || ret == ERR_PTR(-ENOKEY)) |
| 496 | key_ref = ERR_PTR(-ENOKEY); |
| 497 | else if (err == ERR_PTR(-EACCES)) |
| 498 | key_ref = ret; |
| 499 | else |
| 500 | key_ref = err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 502 | found: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 503 | return key_ref; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 504 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 507 | * See if the key we're looking at is the target key. |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 508 | */ |
David Howells | 0c903ab | 2014-09-16 17:36:08 +0100 | [diff] [blame] | 509 | bool lookup_user_key_possessed(const struct key *key, |
| 510 | const struct key_match_data *match_data) |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 511 | { |
David Howells | 4629195 | 2014-09-16 17:36:02 +0100 | [diff] [blame] | 512 | return key == match_data->raw_data; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 513 | } |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 514 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 515 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 516 | * Look up a key ID given us by userspace with a given permissions mask to get |
| 517 | * the key it refers to. |
| 518 | * |
| 519 | * Flags can be passed to request that special keyrings be created if referred |
| 520 | * to directly, to permit partially constructed keys to be found and to skip |
| 521 | * validity and permission checks on the found key. |
| 522 | * |
| 523 | * Returns a pointer to the key with an incremented usage count if successful; |
| 524 | * -EINVAL if the key ID is invalid; -ENOKEY if the key ID does not correspond |
| 525 | * to a key or the best found key was a negative key; -EKEYREVOKED or |
| 526 | * -EKEYEXPIRED if the best found key was revoked or expired; -EACCES if the |
| 527 | * found key doesn't grant the requested permit or the LSM denied access to it; |
| 528 | * or -ENOMEM if a special keyring couldn't be created. |
| 529 | * |
| 530 | * In the case of a successful return, the possession attribute is set on the |
| 531 | * returned key reference. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | */ |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 533 | key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags, |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 534 | key_perm_t perm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 535 | { |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 536 | struct keyring_search_context ctx = { |
David Howells | 4629195 | 2014-09-16 17:36:02 +0100 | [diff] [blame] | 537 | .match_data.cmp = lookup_user_key_possessed, |
| 538 | .match_data.lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, |
| 539 | .flags = KEYRING_SEARCH_NO_STATE_CHECK, |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 540 | }; |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 541 | struct request_key_auth *rka; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | struct key *key; |
David Howells | b6dff3e | 2008-11-14 10:39:16 +1100 | [diff] [blame] | 543 | key_ref_t key_ref, skey_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | int ret; |
| 545 | |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 546 | try_again: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 547 | ctx.cred = get_current_cred(); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 548 | key_ref = ERR_PTR(-ENOKEY); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | |
| 550 | switch (id) { |
| 551 | case KEY_SPEC_THREAD_KEYRING: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 552 | if (!ctx.cred->thread_keyring) { |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 553 | if (!(lflags & KEY_LOOKUP_CREATE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | goto error; |
| 555 | |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 556 | ret = install_thread_keyring(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | if (ret < 0) { |
Dan Carpenter | 4d09ec0 | 2010-05-17 14:42:35 +0100 | [diff] [blame] | 558 | key_ref = ERR_PTR(ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | goto error; |
| 560 | } |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 561 | goto reget_creds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | } |
| 563 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 564 | key = ctx.cred->thread_keyring; |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 565 | __key_get(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 566 | key_ref = make_key_ref(key, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | break; |
| 568 | |
| 569 | case KEY_SPEC_PROCESS_KEYRING: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 570 | if (!ctx.cred->process_keyring) { |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 571 | if (!(lflags & KEY_LOOKUP_CREATE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | goto error; |
| 573 | |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 574 | ret = install_process_keyring(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 575 | if (ret < 0) { |
Dan Carpenter | 4d09ec0 | 2010-05-17 14:42:35 +0100 | [diff] [blame] | 576 | key_ref = ERR_PTR(ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | goto error; |
| 578 | } |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 579 | goto reget_creds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | } |
| 581 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 582 | key = ctx.cred->process_keyring; |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 583 | __key_get(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 584 | key_ref = make_key_ref(key, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 585 | break; |
| 586 | |
| 587 | case KEY_SPEC_SESSION_KEYRING: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 588 | if (!ctx.cred->session_keyring) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | /* always install a session keyring upon access if one |
| 590 | * doesn't exist yet */ |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 591 | ret = install_user_keyrings(); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 592 | if (ret < 0) |
| 593 | goto error; |
David Howells | 3ecf1b4 | 2011-08-22 14:08:43 +0100 | [diff] [blame] | 594 | if (lflags & KEY_LOOKUP_CREATE) |
| 595 | ret = join_session_keyring(NULL); |
| 596 | else |
| 597 | ret = install_session_keyring( |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 598 | ctx.cred->user->session_keyring); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 599 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | if (ret < 0) |
| 601 | goto error; |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 602 | goto reget_creds; |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 603 | } else if (ctx.cred->session_keyring == |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 604 | READ_ONCE(ctx.cred->user->session_keyring) && |
David Howells | 3ecf1b4 | 2011-08-22 14:08:43 +0100 | [diff] [blame] | 605 | lflags & KEY_LOOKUP_CREATE) { |
| 606 | ret = join_session_keyring(NULL); |
| 607 | if (ret < 0) |
| 608 | goto error; |
| 609 | goto reget_creds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | } |
| 611 | |
Jann Horn | 5c7e372 | 2019-03-27 16:39:38 +0100 | [diff] [blame] | 612 | key = ctx.cred->session_keyring; |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 613 | __key_get(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 614 | key_ref = make_key_ref(key, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | break; |
| 616 | |
| 617 | case KEY_SPEC_USER_KEYRING: |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 618 | if (!READ_ONCE(ctx.cred->user->uid_keyring)) { |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 619 | ret = install_user_keyrings(); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 620 | if (ret < 0) |
| 621 | goto error; |
| 622 | } |
| 623 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 624 | key = ctx.cred->user->uid_keyring; |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 625 | __key_get(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 626 | key_ref = make_key_ref(key, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | break; |
| 628 | |
| 629 | case KEY_SPEC_USER_SESSION_KEYRING: |
Jann Horn | 0b9dc6c | 2019-03-27 16:55:08 +0100 | [diff] [blame] | 630 | if (!READ_ONCE(ctx.cred->user->session_keyring)) { |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 631 | ret = install_user_keyrings(); |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 632 | if (ret < 0) |
| 633 | goto error; |
| 634 | } |
| 635 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 636 | key = ctx.cred->user->session_keyring; |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 637 | __key_get(key); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 638 | key_ref = make_key_ref(key, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 639 | break; |
| 640 | |
| 641 | case KEY_SPEC_GROUP_KEYRING: |
| 642 | /* group keyrings are not yet supported */ |
Dan Carpenter | 4d09ec0 | 2010-05-17 14:42:35 +0100 | [diff] [blame] | 643 | key_ref = ERR_PTR(-EINVAL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | goto error; |
| 645 | |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 646 | case KEY_SPEC_REQKEY_AUTH_KEY: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 647 | key = ctx.cred->request_key_auth; |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 648 | if (!key) |
| 649 | goto error; |
| 650 | |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 651 | __key_get(key); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 652 | key_ref = make_key_ref(key, 1); |
| 653 | break; |
| 654 | |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 655 | case KEY_SPEC_REQUESTOR_KEYRING: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 656 | if (!ctx.cred->request_key_auth) |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 657 | goto error; |
| 658 | |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 659 | down_read(&ctx.cred->request_key_auth->sem); |
Dan Carpenter | f67dabb | 2012-03-06 13:32:16 +0000 | [diff] [blame] | 660 | if (test_bit(KEY_FLAG_REVOKED, |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 661 | &ctx.cred->request_key_auth->flags)) { |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 662 | key_ref = ERR_PTR(-EKEYREVOKED); |
| 663 | key = NULL; |
| 664 | } else { |
David Howells | 146aa8b | 2015-10-21 14:04:48 +0100 | [diff] [blame] | 665 | rka = ctx.cred->request_key_auth->payload.data[0]; |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 666 | key = rka->dest_keyring; |
David Howells | ccc3e6d | 2013-09-24 10:35:16 +0100 | [diff] [blame] | 667 | __key_get(key); |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 668 | } |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 669 | up_read(&ctx.cred->request_key_auth->sem); |
David Howells | 8bbf4976 | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 670 | if (!key) |
| 671 | goto error; |
| 672 | key_ref = make_key_ref(key, 1); |
| 673 | break; |
| 674 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | default: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 676 | key_ref = ERR_PTR(-EINVAL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | if (id < 1) |
| 678 | goto error; |
| 679 | |
| 680 | key = key_lookup(id); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 681 | if (IS_ERR(key)) { |
David Howells | e231c2e | 2008-02-07 00:15:26 -0800 | [diff] [blame] | 682 | key_ref = ERR_CAST(key); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | goto error; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 684 | } |
| 685 | |
| 686 | key_ref = make_key_ref(key, 0); |
| 687 | |
| 688 | /* check to see if we possess the key */ |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 689 | ctx.index_key.type = key->type; |
| 690 | ctx.index_key.description = key->description; |
| 691 | ctx.index_key.desc_len = strlen(key->description); |
David Howells | 4629195 | 2014-09-16 17:36:02 +0100 | [diff] [blame] | 692 | ctx.match_data.raw_data = key; |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 693 | kdebug("check possessed"); |
| 694 | skey_ref = search_process_keyrings(&ctx); |
| 695 | kdebug("possessed=%p", skey_ref); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 696 | |
| 697 | if (!IS_ERR(skey_ref)) { |
| 698 | key_put(key); |
| 699 | key_ref = skey_ref; |
| 700 | } |
| 701 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 702 | break; |
| 703 | } |
| 704 | |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 705 | /* unlink does not use the nominated key in any way, so can skip all |
| 706 | * the permission checks as it is only concerned with the keyring */ |
| 707 | if (lflags & KEY_LOOKUP_FOR_UNLINK) { |
| 708 | ret = 0; |
| 709 | goto error; |
| 710 | } |
| 711 | |
| 712 | if (!(lflags & KEY_LOOKUP_PARTIAL)) { |
David Howells | 76181c1 | 2007-10-16 23:29:46 -0700 | [diff] [blame] | 713 | ret = wait_for_key_construction(key, true); |
| 714 | switch (ret) { |
| 715 | case -ERESTARTSYS: |
| 716 | goto invalid_key; |
| 717 | default: |
| 718 | if (perm) |
| 719 | goto invalid_key; |
| 720 | case 0: |
| 721 | break; |
| 722 | } |
| 723 | } else if (perm) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | ret = key_validate(key); |
| 725 | if (ret < 0) |
| 726 | goto invalid_key; |
| 727 | } |
| 728 | |
| 729 | ret = -EIO; |
David Howells | 5593122 | 2009-09-02 09:13:45 +0100 | [diff] [blame] | 730 | if (!(lflags & KEY_LOOKUP_PARTIAL) && |
David Howells | 363b02d | 2017-10-04 16:43:25 +0100 | [diff] [blame] | 731 | key_read_state(key) == KEY_IS_UNINSTANTIATED) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | goto invalid_key; |
| 733 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 734 | /* check the permissions */ |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 735 | ret = key_task_permission(key_ref, ctx.cred, perm); |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 736 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | goto invalid_key; |
| 738 | |
Baolin Wang | 074d589 | 2017-11-15 16:38:45 +0000 | [diff] [blame] | 739 | key->last_used_at = ktime_get_real_seconds(); |
David Howells | 31d5a79 | 2012-05-11 10:56:56 +0100 | [diff] [blame] | 740 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 741 | error: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 742 | put_cred(ctx.cred); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 743 | return key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 745 | invalid_key: |
| 746 | key_ref_put(key_ref); |
| 747 | key_ref = ERR_PTR(ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 748 | goto error; |
| 749 | |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 750 | /* if we attempted to install a keyring, then it may have caused new |
| 751 | * creds to be installed */ |
| 752 | reget_creds: |
David Howells | 4bdf0bc | 2013-09-24 10:35:15 +0100 | [diff] [blame] | 753 | put_cred(ctx.cred); |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 754 | goto try_again; |
David Howells | a8b17ed | 2011-01-20 16:38:27 +0000 | [diff] [blame] | 755 | } |
Dave Jiang | 76ef5e1 | 2018-12-04 10:31:27 -0800 | [diff] [blame] | 756 | EXPORT_SYMBOL(lookup_user_key); |
David Howells | bb952bb | 2008-11-14 10:39:20 +1100 | [diff] [blame] | 757 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 759 | * Join the named keyring as the session keyring if possible else attempt to |
| 760 | * create a new one of that name and join that. |
| 761 | * |
| 762 | * If the name is NULL, an empty anonymous keyring will be installed as the |
| 763 | * session keyring. |
| 764 | * |
| 765 | * Named session keyrings are joined with a semaphore held to prevent the |
| 766 | * keyrings from going away whilst the attempt is made to going them and also |
| 767 | * to prevent a race in creating compatible session keyrings. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | */ |
| 769 | long join_session_keyring(const char *name) |
| 770 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 771 | const struct cred *old; |
| 772 | struct cred *new; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | struct key *keyring; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 774 | long ret, serial; |
| 775 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 776 | new = prepare_creds(); |
| 777 | if (!new) |
| 778 | return -ENOMEM; |
| 779 | old = current_cred(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | |
| 781 | /* if no name is provided, install an anonymous keyring */ |
| 782 | if (!name) { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 783 | ret = install_session_keyring_to_cred(new, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | if (ret < 0) |
| 785 | goto error; |
| 786 | |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 787 | serial = new->session_keyring->serial; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 788 | ret = commit_creds(new); |
| 789 | if (ret == 0) |
| 790 | ret = serial; |
| 791 | goto okay; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 792 | } |
| 793 | |
| 794 | /* allow the user to join or create a named keyring */ |
Ingo Molnar | bb003079 | 2006-03-22 00:09:14 -0800 | [diff] [blame] | 795 | mutex_lock(&key_session_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | |
| 797 | /* look for an existing keyring of this name */ |
David Howells | 69664cf | 2008-04-29 01:01:31 -0700 | [diff] [blame] | 798 | keyring = find_keyring_by_name(name, false); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 799 | if (PTR_ERR(keyring) == -ENOKEY) { |
| 800 | /* not found - try and create a new one */ |
David Howells | 96b5c8f | 2012-10-02 19:24:56 +0100 | [diff] [blame] | 801 | keyring = keyring_alloc( |
| 802 | name, old->uid, old->gid, old, |
| 803 | KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_LINK, |
David Howells | 5ac7eac | 2016-04-06 16:14:24 +0100 | [diff] [blame] | 804 | KEY_ALLOC_IN_QUOTA, NULL, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | if (IS_ERR(keyring)) { |
| 806 | ret = PTR_ERR(keyring); |
David Howells | bcf945d | 2005-08-04 13:07:06 -0700 | [diff] [blame] | 807 | goto error2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | } |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 809 | } else if (IS_ERR(keyring)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | ret = PTR_ERR(keyring); |
| 811 | goto error2; |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 812 | } else if (keyring == new->session_keyring) { |
| 813 | ret = 0; |
Eric Biggers | d636bd9 | 2017-06-08 14:48:03 +0100 | [diff] [blame] | 814 | goto error3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | } |
| 816 | |
| 817 | /* we've got a keyring - now to install it */ |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 818 | ret = install_session_keyring_to_cred(new, keyring); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | if (ret < 0) |
Eric Biggers | d636bd9 | 2017-06-08 14:48:03 +0100 | [diff] [blame] | 820 | goto error3; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 821 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 822 | commit_creds(new); |
| 823 | mutex_unlock(&key_session_mutex); |
| 824 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | ret = keyring->serial; |
| 826 | key_put(keyring); |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 827 | okay: |
| 828 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | |
Eric Biggers | d636bd9 | 2017-06-08 14:48:03 +0100 | [diff] [blame] | 830 | error3: |
| 831 | key_put(keyring); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 832 | error2: |
Ingo Molnar | bb003079 | 2006-03-22 00:09:14 -0800 | [diff] [blame] | 833 | mutex_unlock(&key_session_mutex); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 834 | error: |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 835 | abort_creds(new); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 836 | return ret; |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 837 | } |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 838 | |
| 839 | /* |
David Howells | 973c9f4 | 2011-01-20 16:38:33 +0000 | [diff] [blame] | 840 | * Replace a process's session keyring on behalf of one of its children when |
| 841 | * the target process is about to resume userspace execution. |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 842 | */ |
Al Viro | 67d1214 | 2012-06-27 11:07:19 +0400 | [diff] [blame] | 843 | void key_change_session_keyring(struct callback_head *twork) |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 844 | { |
Oleg Nesterov | 413cd3d | 2012-05-11 10:59:08 +1000 | [diff] [blame] | 845 | const struct cred *old = current_cred(); |
Al Viro | 67d1214 | 2012-06-27 11:07:19 +0400 | [diff] [blame] | 846 | struct cred *new = container_of(twork, struct cred, rcu); |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 847 | |
Oleg Nesterov | 413cd3d | 2012-05-11 10:59:08 +1000 | [diff] [blame] | 848 | if (unlikely(current->flags & PF_EXITING)) { |
| 849 | put_cred(new); |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 850 | return; |
Oleg Nesterov | 413cd3d | 2012-05-11 10:59:08 +1000 | [diff] [blame] | 851 | } |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 852 | |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 853 | new-> uid = old-> uid; |
| 854 | new-> euid = old-> euid; |
| 855 | new-> suid = old-> suid; |
| 856 | new->fsuid = old->fsuid; |
| 857 | new-> gid = old-> gid; |
| 858 | new-> egid = old-> egid; |
| 859 | new-> sgid = old-> sgid; |
| 860 | new->fsgid = old->fsgid; |
| 861 | new->user = get_uid(old->user); |
Eric W. Biederman | ba0e342 | 2013-03-02 19:14:03 -0800 | [diff] [blame] | 862 | new->user_ns = get_user_ns(old->user_ns); |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 863 | new->group_info = get_group_info(old->group_info); |
| 864 | |
| 865 | new->securebits = old->securebits; |
| 866 | new->cap_inheritable = old->cap_inheritable; |
| 867 | new->cap_permitted = old->cap_permitted; |
| 868 | new->cap_effective = old->cap_effective; |
Andy Lutomirski | 5831905 | 2015-09-04 15:42:45 -0700 | [diff] [blame] | 869 | new->cap_ambient = old->cap_ambient; |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 870 | new->cap_bset = old->cap_bset; |
| 871 | |
| 872 | new->jit_keyring = old->jit_keyring; |
| 873 | new->thread_keyring = key_get(old->thread_keyring); |
David Howells | 3a50597 | 2012-10-02 19:24:29 +0100 | [diff] [blame] | 874 | new->process_keyring = key_get(old->process_keyring); |
David Howells | ee18d64 | 2009-09-02 09:14:21 +0100 | [diff] [blame] | 875 | |
| 876 | security_transfer_creds(new, old); |
| 877 | |
| 878 | commit_creds(new); |
| 879 | } |
Mimi Zohar | c124bde | 2013-09-04 13:26:22 +0100 | [diff] [blame] | 880 | |
| 881 | /* |
| 882 | * Make sure that root's user and user-session keyrings exist. |
| 883 | */ |
| 884 | static int __init init_root_keyring(void) |
| 885 | { |
| 886 | return install_user_keyrings(); |
| 887 | } |
| 888 | |
| 889 | late_initcall(init_root_keyring); |