* http://www.us.kernel.org/pub/linux/libs/pam/FAQ
*
* PAM Application Developers' Guide:
- * http://www.us.kernel.org/pub/linux/libs/pam/Linux-PAM-html/pam_appl.html
+ * http://www.us.kernel.org/pub/linux/libs/pam/Linux-PAM-html/Linux-PAM_ADG.html
*
* PAM Mailing list archives:
* http://www.linuxhq.com/lnxlists/linux-pam/
#include <security/pam_appl.h>
#include <signal.h>
#include <errno.h>
+#include <X11/Intrinsic.h>
#include <sys/stat.h>
+#include "auth.h"
+
extern sigset_t block_sigchld (void);
extern void unblock_sigchld (void);
struct pam_response **resp,
void *closure);
-struct pam_closure {
- const char *user;
- const char *typed_passwd;
- Bool verbose_p;
-};
+void pam_try_unlock(saver_info *si, Bool verbose_p,
+ Bool (*valid_p)(const char *typed_passwd, Bool verbose_p));
-Bool pam_passwd_valid_p (const char *typed_passwd, Bool verbose_p);
Bool pam_priv_init (int argc, char **argv, Bool verbose_p);
#ifdef HAVE_PAM_FAIL_DELAY
static void *suns_pam_implementation_blows = 0;
-/* This can be called at any time, and says whether the typed password
- belongs to either the logged in user (real uid, not effective); or
- to root.
+/**
+ * This function is the PAM conversation driver. It conducts a full
+ * authentication round by invoking the GUI with various prompts.
*/
-Bool
-pam_passwd_valid_p (const char *typed_passwd, Bool verbose_p)
+void
+pam_try_unlock(saver_info *si, Bool verbose_p,
+ Bool (*valid_p)(const char *typed_passwd, Bool verbose_p))
{
const char *service = PAM_SERVICE_NAME;
pam_handle_t *pamh = 0;
int status = -1;
struct pam_conv pc;
- struct pam_closure c;
- char *user = 0;
sigset_t set;
struct timespec timeout;
- struct passwd *p = getpwuid (getuid ());
- if (!p) return False;
-
- user = strdup (p->pw_name);
-
- c.user = user;
- c.typed_passwd = typed_passwd;
- c.verbose_p = verbose_p;
-
pc.conv = &pam_conversation;
- pc.appdata_ptr = (void *) &c;
+ pc.appdata_ptr = (void *) si;
/* On SunOS 5.6, the `appdata_ptr' slot seems to be ignored, and the
`closure' argument to pc.conv always comes in as random garbage. */
- suns_pam_implementation_blows = (void *) &c;
+ suns_pam_implementation_blows = (void *) si;
/* Initialize PAM.
*/
- status = pam_start (service, c.user, &pc, &pamh);
+ status = pam_start (service, si->user, &pc, &pamh);
if (verbose_p)
fprintf (stderr, "%s: pam_start (\"%s\", \"%s\", ...) ==> %d (%s)\n",
- blurb(), service, c.user,
+ blurb(), service, si->user,
status, PAM_STRERROR (pamh, status));
if (status != PAM_SUCCESS) goto DONE;
if (verbose_p)
fprintf (stderr, "%s: pam_authenticate (...) ==> %d (%s)\n",
blurb(), status, PAM_STRERROR(pamh, status));
+
if (status == PAM_SUCCESS) /* Win! */
{
int status2;
fprintf (stderr, "%s: pam_acct_mgmt (...) ==> %d (%s)\n",
blurb(), status2, PAM_STRERROR(pamh, status2));
+ /* HPUX for some reason likes to make PAM defines different from
+ * everyone else's. */
+#ifdef PAM_AUTHTOKEN_REQD
+ if (status2 == PAM_AUTHTOKEN_REQD)
+#else
+ if (status2 == PAM_NEW_AUTHTOK_REQD)
+#endif
+ {
+ status2 = pam_chauthtok (pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
+ if (verbose_p)
+ fprintf (stderr, "%s: pam_chauthtok (...) ==> %d (%s)\n",
+ blurb(), status2, PAM_STRERROR(pamh, status2));
+ }
+
/* Each time we successfully authenticate, refresh credentials,
for Kerberos/AFS/DCE/etc. If this fails, just ignore that
failure and blunder along; it shouldn't matter.
if (verbose_p)
fprintf (stderr, "%s: pam_setcred (...) ==> %d (%s)\n",
blurb(), status2, PAM_STRERROR(pamh, status2));
- goto DONE;
}
-#ifdef ALLOW_ROOT_PASSWD
- /* If that didn't work, set the user to root, and try to authenticate again.
- */
- if (user) free (user);
- user = strdup ("root");
- c.user = user;
- status = pam_set_item (pamh, PAM_USER, c.user);
- if (verbose_p)
- fprintf (stderr, "%s: pam_set_item(p, PAM_USER, \"%s\") ==> %d (%s)\n",
- blurb(), c.user, status, PAM_STRERROR(pamh, status));
- if (status != PAM_SUCCESS) goto DONE;
-
- PAM_NO_DELAY(pamh);
-
- set = block_sigchld();
- status = pam_authenticate (pamh, 0);
- sigtimedwait(&set, NULL, &timeout);
- unblock_sigchld();
-
- if (verbose_p)
- fprintf (stderr, "%s: pam_authenticate (...) ==> %d (%s)\n",
- blurb(), status, PAM_STRERROR(pamh, status));
-
-#endif /* ALLOW_ROOT_PASSWD */
-
DONE:
- if (user) free (user);
if (pamh)
{
int status2 = pam_end (pamh, status);
blurb(), status2,
(status2 == PAM_SUCCESS ? "Success" : "Failure"));
}
- return (status == PAM_SUCCESS ? True : False);
+
+ si->unlock_state = (status == PAM_SUCCESS) ? ul_success : ul_fail;
}
}
-/* This is the function PAM calls to have a conversation with the user.
- Really, this function should be the thing that pops up dialog boxes
- as needed, and prompts for various strings.
-
- But, for now, xscreensaver uses its normal password-prompting dialog
- first, and then this function simply returns the result that has been
- typed.
-
- This means that if PAM was using a retina scanner for auth, xscreensaver
- would prompt for a password; then pam_conversation() would be called
- with a string like "Please look into the retina scanner". The user
- would never see this string, and the prompted-for password would be
- ignored.
- */
static int
pam_conversation (int nmsgs,
- const struct pam_message **msg,
- struct pam_response **resp,
- void *closure)
+ const struct pam_message **msg,
+ struct pam_response **resp,
+ void *vsaver_info)
{
- int replies = 0;
- struct pam_response *reply = 0;
- struct pam_closure *c = (struct pam_closure *) closure;
+ int i, ret = -1;
+ struct auth_message *messages = 0;
+ struct auth_response *authresp = 0;
+ struct pam_response *pam_responses;
+ saver_info *si = (saver_info *) vsaver_info;
/* On SunOS 5.6, the `closure' argument always comes in as random garbage. */
- c = (struct pam_closure *) suns_pam_implementation_blows;
+ si = (saver_info *) suns_pam_implementation_blows;
+
+ /* Converting the PAM prompts into the XScreenSaver native format.
+ * It was a design goal to collapse (INFO,PROMPT) pairs from PAM
+ * into a single call to the unlock_cb function. The unlock_cb function
+ * does that, but only if it is passed several prompts at a time. Most PAM
+ * modules only send a single prompt at a time, but because there is no way
+ * of telling whether there will be more prompts to follow, we can only ever
+ * pass along whatever was passed in here.
+ */
+ messages = calloc(nmsgs, sizeof(struct auth_message));
+ pam_responses = calloc(nmsgs, sizeof(*pam_responses));
+
+ if (!pam_responses || !messages)
+ goto end;
- reply = (struct pam_response *) calloc (nmsgs, sizeof (*reply));
- if (!reply) return PAM_CONV_ERR;
-
- for (replies = 0; replies < nmsgs; replies++)
+ for (i = 0; i < nmsgs; ++i)
{
- switch (msg[replies]->msg_style)
- {
- case PAM_PROMPT_ECHO_ON:
- reply[replies].resp_retcode = PAM_SUCCESS;
- reply[replies].resp = strdup (c->user); /* freed by PAM */
- if (c->verbose_p)
- fprintf (stderr, "%s: PAM ECHO_ON(\"%s\") ==> \"%s\"\n",
- blurb(), msg[replies]->msg,
- reply[replies].resp);
- break;
- case PAM_PROMPT_ECHO_OFF:
- reply[replies].resp_retcode = PAM_SUCCESS;
- reply[replies].resp = strdup (c->typed_passwd); /* freed by PAM */
- if (c->verbose_p)
- fprintf (stderr, "%s: PAM ECHO_OFF(\"%s\") ==> password\n",
- blurb(), msg[replies]->msg);
- break;
- case PAM_TEXT_INFO:
- /* ignore it... */
- reply[replies].resp_retcode = PAM_SUCCESS;
- reply[replies].resp = 0;
- if (c->verbose_p)
- fprintf (stderr, "%s: PAM TEXT_INFO(\"%s\") ==> ignored\n",
- blurb(), msg[replies]->msg);
- break;
- case PAM_ERROR_MSG:
- /* ignore it... */
- reply[replies].resp_retcode = PAM_SUCCESS;
- reply[replies].resp = 0;
- if (c->verbose_p)
- fprintf (stderr, "%s: PAM ERROR_MSG(\"%s\") ==> ignored\n",
- blurb(), msg[replies]->msg);
- break;
- default:
- /* Must be an error of some sort... */
- free (reply);
- if (c->verbose_p)
- fprintf (stderr, "%s: PAM unknown %d(\"%s\") ==> ignored\n",
- blurb(), msg[replies]->msg_style, msg[replies]->msg);
- return PAM_CONV_ERR;
- }
+ messages[i].msg = msg[i]->msg;
+
+ /* Default fallback of PROMPT_ECHO */
+ messages[i].type =
+ msg[i]->msg_style == PAM_PROMPT_ECHO_OFF
+ ? AUTH_MSGTYPE_PROMPT_NOECHO
+ : msg[i]->msg_style == PAM_PROMPT_ECHO_ON
+ ? AUTH_MSGTYPE_PROMPT_ECHO
+ : msg[i]->msg_style == PAM_ERROR_MSG
+ ? AUTH_MSGTYPE_ERROR
+ : msg[i]->msg_style == PAM_TEXT_INFO
+ ? AUTH_MSGTYPE_INFO
+ : AUTH_MSGTYPE_PROMPT_ECHO;
}
- *resp = reply;
- return PAM_SUCCESS;
+
+ ret = si->unlock_cb(nmsgs, messages, &authresp, si);
+
+ if (ret == 0)
+ {
+ for (i = 0; i < nmsgs; ++i)
+ pam_responses[i].resp = authresp[i].response;
+ }
+
+end:
+ if (messages)
+ free(messages);
+
+ if (authresp)
+ free(authresp);
+
+ if (ret == 0)
+ {
+ *resp = pam_responses;
+ return PAM_SUCCESS;
+ }
+
+ /* Failure only */
+ if (pam_responses)
+ free(pam_responses);
+
+ return PAM_CONV_ERR;
}
#endif /* NO_LOCKING -- whole file */
projects / xscreensaver / blobdiff