- (djm) Add Steve VanDevender's <stevev@darkwing.uoregon.edu> PAM
password change patch.
- (djm) Bring licenses on my stuff in line with OpenBSD's
diff --git a/auth-pam.c b/auth-pam.c
index e2bac9e..5914cab 100644
--- a/auth-pam.c
+++ b/auth-pam.c
@@ -9,11 +9,6 @@
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by Markus Friedl.
- * 4. The name of the author may not be used to endorse or promote products
- * derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
@@ -34,10 +29,10 @@
#include "xmalloc.h"
#include "servconf.h"
-RCSID("$Id: auth-pam.c,v 1.12 2000/08/29 22:57:50 djm Exp $");
+RCSID("$Id: auth-pam.c,v 1.13 2000/09/16 05:09:27 djm Exp $");
#define NEW_AUTHTOK_MSG \
- "Warning: You password has expired, please change it now"
+ "Warning: Your password has expired, please change it now"
/* Callbacks */
static int pamconv(int num_msg, const struct pam_message **msg,
@@ -50,40 +45,72 @@
pamconv,
NULL
};
-static struct pam_handle_t *pamh = NULL;
+static pam_handle_t *pamh = NULL;
static const char *pampasswd = NULL;
static char *pam_msg = NULL;
-/* PAM conversation function. This is really a kludge to get the password */
-/* into PAM and to pick up any messages generated by PAM into pamconv_msg */
+/* states for pamconv() */
+typedef enum { INITIAL_LOGIN, OTHER } pamstates;
+static pamstates pamstate = INITIAL_LOGIN;
+/* remember whether pam_acct_mgmt() returned PAM_NEWAUTHTOK_REQD */
+static int password_change_required = 0;
+
+/*
+ * PAM conversation function.
+ * There are two states this can run in.
+ *
+ * INITIAL_LOGIN mode simply feeds the password from the client into
+ * PAM in response to PAM_PROMPT_ECHO_OFF, and collects output
+ * messages with pam_msg_cat(). This is used during initial
+ * authentication to bypass the normal PAM password prompt.
+ *
+ * OTHER mode handles PAM_PROMPT_ECHO_OFF with read_passphrase(prompt, 1)
+ * and outputs messages to stderr. This mode is used if pam_chauthtok()
+ * is called to update expired passwords.
+ */
static int pamconv(int num_msg, const struct pam_message **msg,
struct pam_response **resp, void *appdata_ptr)
{
struct pam_response *reply;
int count;
+ char buf[1024];
/* PAM will free this later */
reply = malloc(num_msg * sizeof(*reply));
if (reply == NULL)
return PAM_CONV_ERR;
- for(count = 0; count < num_msg; count++) {
- switch (msg[count]->msg_style) {
- case PAM_PROMPT_ECHO_OFF:
- if (pampasswd == NULL) {
- free(reply);
- return PAM_CONV_ERR;
- }
+ for (count = 0; count < num_msg; count++) {
+ switch ((*msg)[count].msg_style) {
+ case PAM_PROMPT_ECHO_ON:
+ fputs((*msg)[count].msg, stderr);
+ fgets(buf, sizeof(buf), stdin);
+ reply[count].resp = xstrdup(buf);
reply[count].resp_retcode = PAM_SUCCESS;
- reply[count].resp = xstrdup(pampasswd);
break;
- case PAM_TEXT_INFO:
+ case PAM_PROMPT_ECHO_OFF:
+ if (pamstate == INITIAL_LOGIN) {
+ if (pampasswd == NULL) {
+ free(reply);
+ return PAM_CONV_ERR;
+ }
+ reply[count].resp = xstrdup(pampasswd);
+ } else
+ reply[count].resp = xstrdup(read_passphrase((*msg)[count].msg, 1));
reply[count].resp_retcode = PAM_SUCCESS;
+ break;
+ case PAM_ERROR_MSG:
+ case PAM_TEXT_INFO:
+ if ((*msg)[count].msg != NULL) {
+ if (pamstate == INITIAL_LOGIN)
+ pam_msg_cat((*msg)[count].msg);
+ else {
+ fputs((*msg)[count].msg, stderr);
+ fputs("\n", stderr);
+ }
+ }
reply[count].resp = xstrdup("");
-
- if (msg[count]->msg != NULL)
- pam_msg_cat(msg[count]->msg);
-
+ reply[count].resp_retcode = PAM_SUCCESS;
break;
default:
free(reply);
@@ -103,22 +130,22 @@
if (pamh != NULL)
{
- pam_retval = pam_close_session((pam_handle_t *)pamh, 0);
+ pam_retval = pam_close_session(pamh, 0);
if (pam_retval != PAM_SUCCESS) {
log("Cannot close PAM session: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
- pam_retval = pam_setcred((pam_handle_t *)pamh, PAM_DELETE_CRED);
+ pam_retval = pam_setcred(pamh, PAM_DELETE_CRED);
if (pam_retval != PAM_SUCCESS) {
debug("Cannot delete credentials: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
- pam_retval = pam_end((pam_handle_t *)pamh, pam_retval);
+ pam_retval = pam_end(pamh, pam_retval);
if (pam_retval != PAM_SUCCESS) {
log("Cannot release PAM authentication: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
}
}
@@ -139,14 +166,15 @@
pampasswd = password;
- pam_retval = pam_authenticate((pam_handle_t *)pamh, 0);
+ pamstate = INITIAL_LOGIN;
+ pam_retval = pam_authenticate(pamh, 0);
if (pam_retval == PAM_SUCCESS) {
debug("PAM Password authentication accepted for user \"%.100s\"",
pw->pw_name);
return 1;
} else {
debug("PAM Password authentication for \"%.100s\" failed: %s",
- pw->pw_name, PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ pw->pw_name, PAM_STRERROR(pamh, pam_retval));
return 0;
}
}
@@ -157,33 +185,35 @@
int pam_retval;
debug("PAM setting rhost to \"%.200s\"", get_canonical_hostname());
- pam_retval = pam_set_item((pam_handle_t *)pamh, PAM_RHOST,
+ pam_retval = pam_set_item(pamh, PAM_RHOST,
get_canonical_hostname());
if (pam_retval != PAM_SUCCESS) {
fatal("PAM set rhost failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
if (remote_user != NULL) {
debug("PAM setting ruser to \"%.200s\"", remote_user);
- pam_retval = pam_set_item((pam_handle_t *)pamh, PAM_RUSER, remote_user);
+ pam_retval = pam_set_item(pamh, PAM_RUSER, remote_user);
if (pam_retval != PAM_SUCCESS) {
fatal("PAM set ruser failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
}
- pam_retval = pam_acct_mgmt((pam_handle_t *)pamh, 0);
+ pam_retval = pam_acct_mgmt(pamh, 0);
switch (pam_retval) {
case PAM_SUCCESS:
/* This is what we want */
break;
case PAM_NEW_AUTHTOK_REQD:
pam_msg_cat(NEW_AUTHTOK_MSG);
+ /* flag that password change is necessary */
+ password_change_required = 1;
break;
default:
log("PAM rejected by account configuration: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
return(0);
}
@@ -197,17 +227,17 @@
if (ttyname != NULL) {
debug("PAM setting tty to \"%.200s\"", ttyname);
- pam_retval = pam_set_item((pam_handle_t *)pamh, PAM_TTY, ttyname);
+ pam_retval = pam_set_item(pamh, PAM_TTY, ttyname);
if (pam_retval != PAM_SUCCESS) {
fatal("PAM set tty failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
}
- pam_retval = pam_open_session((pam_handle_t *)pamh, 0);
+ pam_retval = pam_open_session(pamh, 0);
if (pam_retval != PAM_SUCCESS) {
fatal("PAM session setup failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
}
@@ -217,10 +247,28 @@
int pam_retval;
debug("PAM establishing creds");
- pam_retval = pam_setcred((pam_handle_t *)pamh, PAM_ESTABLISH_CRED);
+ pam_retval = pam_setcred(pamh, PAM_ESTABLISH_CRED);
if (pam_retval != PAM_SUCCESS) {
fatal("PAM setcred failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
+ }
+}
+
+/*
+ * Have user change authentication token if pam_acct_mgmt() indicated
+ * it was expired. This needs to be called after an interactive
+ * session is established and the user's pty is connected to
+ * stdin/stout/stderr.
+ */
+void do_pam_chauthtok()
+{
+ int pam_retval;
+
+ if (password_change_required) {
+ pamstate = OTHER;
+ do {
+ pam_retval = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
+ } while (pam_retval != PAM_SUCCESS);
}
}
@@ -238,12 +286,11 @@
debug("Starting up PAM with username \"%.200s\"", pw->pw_name);
- pam_retval = pam_start(SSHD_PAM_SERVICE, pw->pw_name, &conv,
- (pam_handle_t**)&pamh);
+ pam_retval = pam_start(SSHD_PAM_SERVICE, pw->pw_name, &conv, &pamh);
if (pam_retval != PAM_SUCCESS) {
fatal("PAM initialisation failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
#ifdef PAM_TTY_KLUDGE
@@ -254,10 +301,10 @@
* not even need one (for tty-less connections)
* Kludge: Set a fake PAM_TTY
*/
- pam_retval = pam_set_item((pam_handle_t *)pamh, PAM_TTY, "ssh");
+ pam_retval = pam_set_item(pamh, PAM_TTY, "ssh");
if (pam_retval != PAM_SUCCESS) {
fatal("PAM set tty failed: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
+ PAM_STRERROR(pamh, pam_retval));
}
#endif /* PAM_TTY_KLUDGE */
@@ -268,7 +315,7 @@
char **fetch_pam_environment(void)
{
#ifdef HAVE_PAM_GETENVLIST
- return(pam_getenvlist((pam_handle_t *)pamh));
+ return(pam_getenvlist(pamh));
#else /* HAVE_PAM_GETENVLIST */
return(NULL);
#endif /* HAVE_PAM_GETENVLIST */