/*
* request userspace finish the construction of a key
* - execute "/sbin/request-key <op> <key> <uid> <gid> <keyring> <keyring> <keyring>"
*/
static int call_sbin_request_key(struct key_construction *cons,
const char *op,
void *aux)
{
struct task_struct *tsk = current;
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];
char key_str[12], keyring_str[3][12];
char desc[20];
int ret, i;
kenter("{%d},{%d},%s", key->serial, authkey->serial, op);
ret = install_user_keyrings(tsk);
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,
KEY_ALLOC_QUOTA_OVERRUN, NULL);
if (IS_ERR(keyring)) {
ret = PTR_ERR(keyring);
goto error_alloc;
}
/* attach the auth key to the session keyring */
ret = __key_link(keyring, authkey);
if (ret < 0)
goto error_link;
/* record the UID and GID */
sprintf(uid_str, "%d", current->fsuid);
sprintf(gid_str, "%d", current->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);
prkey = 0;
if (tsk->signal->process_keyring)
prkey = tsk->signal->process_keyring->serial;
sprintf(keyring_str[1], "%d", prkey);
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;
}
sprintf(keyring_str[2], "%d", sskey);
/* set up a minimal environment */
i = 0;
envp[i++] = "HOME=/";
envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
envp[i] = NULL;
/* set up the argument list */
i = 0;
argv[i++] = "/sbin/request-key";
argv[i++] = (char *) op;
argv[i++] = key_str;
argv[i++] = uid_str;
argv[i++] = gid_str;
argv[i++] = keyring_str[0];
argv[i++] = keyring_str[1];
argv[i++] = keyring_str[2];
argv[i] = NULL;
/* do it */
ret = call_usermodehelper_keys(argv[0], argv, envp, keyring,
UMH_WAIT_PROC);
kdebug("usermode -> 0x%x", ret);
if (ret >= 0) {
/* ret is the exit/wait code */
if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags) ||
key_validate(key) < 0)
ret = -ENOKEY;
else
/* ignore any errors from userspace if the key was
* instantiated */
ret = 0;
}
error_link:
key_put(keyring);
error_alloc:
kleave(" = %d", ret);
complete_request_key(cons, ret);
return ret;
}
static int call_sbin_request_key(struct key_construction *cons,
const char *op,
void *aux)
{
const struct cred *cred = current_cred();
key_serial_t prkey, sskey;
struct key *key = cons->key, *authkey = cons->authkey, *keyring,
*session;
char *argv[9], *envp[3], uid_str[12], gid_str[12];
char key_str[12], keyring_str[3][12];
char desc[20];
int ret, i;
kenter("{%d},{%d},%s", key->serial, authkey->serial, op);
ret = install_user_keyrings();
if (ret < 0)
goto error_alloc;
/* */
sprintf(desc, "_req.%u", key->serial);
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;
}
/* */
ret = key_link(keyring, authkey);
if (ret < 0)
goto error_link;
/* */
sprintf(uid_str, "%d", cred->fsuid);
sprintf(gid_str, "%d", cred->fsgid);
/* */
sprintf(key_str, "%d", key->serial);
/* */
sprintf(keyring_str[0], "%d",
cred->thread_keyring ? cred->thread_keyring->serial : 0);
prkey = 0;
if (cred->tgcred->process_keyring)
prkey = cred->tgcred->process_keyring->serial;
sprintf(keyring_str[1], "%d", prkey);
rcu_read_lock();
session = rcu_dereference(cred->tgcred->session_keyring);
if (!session)
session = cred->user->session_keyring;
sskey = session->serial;
rcu_read_unlock();
sprintf(keyring_str[2], "%d", sskey);
/* */
i = 0;
envp[i++] = "HOME=/";
envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
envp[i] = NULL;
/* */
i = 0;
argv[i++] = "/sbin/request-key";
argv[i++] = (char *) op;
argv[i++] = key_str;
argv[i++] = uid_str;
argv[i++] = gid_str;
argv[i++] = keyring_str[0];
argv[i++] = keyring_str[1];
argv[i++] = keyring_str[2];
argv[i] = NULL;
/* */
ret = call_usermodehelper_keys(argv[0], argv, envp, keyring,
UMH_WAIT_PROC);
kdebug("usermode -> 0x%x", ret);
if (ret >= 0) {
/* */
if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags) ||
key_validate(key) < 0)
ret = -ENOKEY;
else
/*
*/
ret = 0;
}
error_link:
key_put(keyring);
error_alloc:
complete_request_key(cons, ret);
kleave(" = %d", ret);
return ret;
}
