Based on an original PAM patch by Andrew Bartlett, re-written by me to
[samba.git] / source3 / passdb / pampass.c
index 9f4a8f57b91a642870dc4592a6da314d10e9de17..83640bf5c86dd5cba3647984a96a8b20eed39785 100644 (file)
@@ -44,31 +44,58 @@ extern int DEBUGLEVEL;
 #include <security/pam_appl.h>
 
 /*
- * Static variables used to communicate between the conversation function
- * and the server_login function
+ * Structure used to communicate between the conversation function
+ * and the server_login/change password functions.
  */
 
-static char *PAM_username;
-static char *PAM_password;
+struct smb_pam_userdata {
+       char *PAM_username;
+       char *PAM_password;
+       char *PAM_newpassword;
+};
+
+typedef int (*smb_pam_conv_fn)(int, const struct pam_message **, struct pam_response **, void *appdata_ptr);
 
 /*
  *  Macros to help make life easy
  */
 #define COPY_STRING(s) (s) ? strdup(s) : NULL
 
-/*
- * PAM error handler.
- */
+/*******************************************************************
+ PAM error handler.
+ *********************************************************************/
+
 static BOOL smb_pam_error_handler(pam_handle_t *pamh, int pam_error, char *msg, int dbglvl)
 {
 
        if( pam_error != PAM_SUCCESS) {
-               DEBUG(dbglvl, ("PAM: %s : %s\n", msg, pam_strerror(pamh, pam_error)));
+               DEBUG(dbglvl, ("smb_pam_error_handler: PAM: %s : %s\n",
+                               msg, pam_strerror(pamh, pam_error)));
                return False;
        }
        return True;
 }
 
+/*******************************************************************
+ This function is a sanity check, to make sure that we NEVER report
+ failure as sucess.
+*********************************************************************/
+
+static BOOL smb_pam_nt_status_error_handler(pam_handle_t *pamh, int pam_error,
+                                                       char *msg, int dbglvl, uint32 *nt_status)
+{
+       if (smb_pam_error_handler(pamh, pam_error, msg, dbglvl))
+               return True;
+
+       if (*nt_status == NT_STATUS_NOPROBLEMO) {
+               /* Complain LOUDLY */
+               DEBUG(0, ("smb_pam_nt_status_error_handler: PAM: BUG: PAM and NT_STATUS \
+error MISMATCH, forcing to NT_STATUS_LOGON_FAILURE"));
+               *nt_status = NT_STATUS_LOGON_FAILURE;
+       }
+       return False;
+}
+
 /*
  * PAM conversation function
  * Here we assume (for now, at least) that echo on means login name, and
@@ -82,6 +109,9 @@ static int smb_pam_conv(int num_msg,
 {
        int replies = 0;
        struct pam_response *reply = NULL;
+       struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
+
+       *resp = NULL;
 
        reply = malloc(sizeof(struct pam_response) * num_msg);
        if (!reply)
@@ -91,15 +121,13 @@ static int smb_pam_conv(int num_msg,
                switch (msg[replies]->msg_style) {
                        case PAM_PROMPT_ECHO_ON:
                                reply[replies].resp_retcode = PAM_SUCCESS;
-                       reply[replies].resp =
-                                       COPY_STRING(PAM_username);
+                               reply[replies].resp = COPY_STRING(udp->PAM_username);
                                /* PAM frees resp */
                                break;
 
                        case PAM_PROMPT_ECHO_OFF:
                                reply[replies].resp_retcode = PAM_SUCCESS;
-                               reply[replies].resp =
-                                       COPY_STRING(PAM_password);
+                               reply[replies].resp = COPY_STRING(udp->PAM_password);
                                /* PAM frees resp */
                                break;
 
@@ -123,41 +151,158 @@ static int smb_pam_conv(int num_msg,
        return PAM_SUCCESS;
 }
 
-static struct pam_conv smb_pam_conversation = {
-       &smb_pam_conv,
-       NULL
-};
+/*
+ * PAM password change conversation function
+ * Here we assume (for now, at least) that echo on means login name, and
+ * echo off means password.
+ */
+
+static int smb_pam_passchange_conv(int num_msg,
+                               const struct pam_message **msg,
+                               struct pam_response **resp,
+                               void *appdata_ptr)
+{
+       int replies = 0;
+       struct pam_response *reply = NULL;
+       fstring currentpw_prompt;
+       fstring newpw_prompt;
+       fstring repeatpw_prompt;
+       char *p = lp_passwd_chat();
+       struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
+
+       /* Get the prompts... */
+
+       if (!next_token(&p, currentpw_prompt, NULL, sizeof(fstring)))
+               return PAM_CONV_ERR;
+       if (!next_token(&p, newpw_prompt, NULL, sizeof(fstring)))
+               return PAM_CONV_ERR;
+       if (!next_token(&p, repeatpw_prompt, NULL, sizeof(fstring)))
+               return PAM_CONV_ERR;
+
+       *resp = NULL;
+
+       reply = malloc(sizeof(struct pam_response) * num_msg);
+       if (!reply)
+               return PAM_CONV_ERR;
+
+       for (replies = 0; replies < num_msg; replies++) {
+               switch (msg[replies]->msg_style) {
+               case PAM_PROMPT_ECHO_ON:
+                       reply[replies].resp_retcode = PAM_SUCCESS;
+                       reply[replies].resp = COPY_STRING(udp->PAM_username);
+                       /* PAM frees resp */
+                       break;
+
+               case PAM_PROMPT_ECHO_OFF:
+                       reply[replies].resp_retcode = PAM_SUCCESS;
+                       DEBUG(10,("smb_pam_passchange_conv: PAM Replied: %s\n", msg[replies]->msg));
+                       if (strncmp(currentpw_prompt, msg[replies]->msg, strlen(currentpw_prompt)) == 0) {
+                               reply[replies].resp = COPY_STRING(udp->PAM_password);
+                       } else if (strncmp(newpw_prompt, msg[replies]->msg, strlen(newpw_prompt)) == 0) {
+                               reply[replies].resp = COPY_STRING(udp->PAM_newpassword);
+                       } else if (strncmp(repeatpw_prompt, msg[replies]->msg, strlen(repeatpw_prompt)) == 0) {
+                               reply[replies].resp = COPY_STRING(udp->PAM_newpassword);
+                       } else {
+                               DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
+                               DEBUG(5,("smb_pam_passchange_conv: Prompts available:\n CurrentPW: \"%s\"\n NewPW: \"%s\"\n \
+RepeatPW: \"%s\"\n",currentpw_prompt,newpw_prompt,repeatpw_prompt));
+                       }
+                       /* PAM frees resp */
+                       break;
+
+               case PAM_TEXT_INFO:
+                       /* fall through */
+
+               case PAM_ERROR_MSG:
+                       /* ignore it... */
+                       reply[replies].resp_retcode = PAM_SUCCESS;
+                       reply[replies].resp = NULL;
+                       break;
+
+               default:
+                       /* Must be an error of some sort... */
+                       free(reply);
+                       reply = NULL;
+                       return PAM_CONV_ERR;
+               }
+       }
+
+       if (reply)
+               *resp = reply;
+       return PAM_SUCCESS;
+}
+
+/***************************************************************************
+ Free up a malloced pam_conv struct.
+****************************************************************************/
+
+static void smb_free_pam_conv(struct pam_conv *pconv)
+{
+       if (pconv)
+               safe_free(pconv->appdata_ptr);
+
+       safe_free(pconv);
+}
+
+/***************************************************************************
+ Allocate a pam_conv struct.
+****************************************************************************/
+
+static struct pam_conv *smb_setup_pam_conv(smb_pam_conv_fn smb_pam_conv_fnptr, char *user,
+                                       char *passwd, char *newpass)
+{
+       struct pam_conv *pconv = (struct pam_conv *)malloc(sizeof(struct pam_conv));
+       struct smb_pam_userdata *udp = (struct smb_pam_userdata *)malloc(sizeof(struct smb_pam_userdata));
+
+       if (pconv == NULL || udp == NULL) {
+               safe_free(pconv);
+               safe_free(udp);
+               return NULL;
+       }
+
+       udp->PAM_username = user;
+       udp->PAM_password = passwd;
+       udp->PAM_newpassword = newpass;
+
+       pconv->conv = smb_pam_conv_fnptr;
+       pconv->appdata_ptr = (void *)udp;
+       return pconv;
+}
 
 /* 
  * PAM Closing out cleanup handler
  */
-static BOOL smb_pam_end(pam_handle_t *pamh)
+
+static BOOL smb_pam_end(pam_handle_t *pamh, struct pam_conv *smb_pam_conv_ptr)
 {
        int pam_error;
+
+       smb_free_pam_conv(smb_pam_conv_ptr);
        
        if( pamh != NULL ) {
                pam_error = pam_end(pamh, 0);
                if(smb_pam_error_handler(pamh, pam_error, "End Cleanup Failed", 2) == True) {
-                       DEBUG(4, ("PAM: PAM_END OK.\n"));
+                       DEBUG(4, ("smb_pam_end: PAM: PAM_END OK.\n"));
                        return True;
                }
        }
-       DEBUG(2,("PAM: not initialised"));
+       DEBUG(2,("smb_pam_end: PAM: not initialised"));
        return False;
 }
 
 /*
  * Start PAM authentication for specified account
  */
-static BOOL smb_pam_start(pam_handle_t **pamh, char *user, char *rhost)
+
+static BOOL smb_pam_start(pam_handle_t **pamh, char *user, char *rhost, struct pam_conv *pconv)
 {
        int pam_error;
 
        *pamh = (pam_handle_t *)NULL;
 
-       DEBUG(4,("PAM: Init user: %s\n", user));
+       DEBUG(4,("smb_pam_start: PAM: Init user: %s\n", user));
 
-       pam_error = pam_start("samba", user, &smb_pam_conversation, pamh);
+       pam_error = pam_start("samba", user, pconv, pamh);
        if( !smb_pam_error_handler(*pamh, pam_error, "Init Failed", 0)) {
                *pamh = (pam_handle_t *)NULL;
                return False;
@@ -170,117 +315,134 @@ static BOOL smb_pam_start(pam_handle_t **pamh, char *user, char *rhost)
        }
 
 #ifdef PAM_RHOST
-       DEBUG(4,("PAM: setting rhost to: %s\n", rhost));
+       DEBUG(4,("smb_pam_start: PAM: setting rhost to: %s\n", rhost));
        pam_error = pam_set_item(*pamh, PAM_RHOST, rhost);
        if(!smb_pam_error_handler(*pamh, pam_error, "set rhost failed", 0)) {
-               smb_pam_end(*pamh);
+               smb_pam_end(*pamh, pconv);
                *pamh = (pam_handle_t *)NULL;
                return False;
        }
 #endif
 #ifdef PAM_TTY
-       DEBUG(4,("PAM: setting tty\n"));
+       DEBUG(4,("smb_pam_start: PAM: setting tty\n"));
        pam_error = pam_set_item(*pamh, PAM_TTY, "samba");
        if (!smb_pam_error_handler(*pamh, pam_error, "set tty failed", 0)) {
-               smb_pam_end(*pamh);
+               smb_pam_end(*pamh, pconv);
                *pamh = (pam_handle_t *)NULL;
                return False;
        }
 #endif
-       DEBUG(4,("PAM: Init passed for user: %s\n", user));
+       DEBUG(4,("smb_pam_start: PAM: Init passed for user: %s\n", user));
        return True;
 }
 
 /*
  * PAM Authentication Handler
  */
-static BOOL smb_pam_auth(pam_handle_t *pamh, char *user, char *password)
+static uint32 smb_pam_auth(pam_handle_t *pamh, char *user)
 {
        int pam_error;
+       uint32 nt_status = NT_STATUS_LOGON_FAILURE;
 
        /*
         * To enable debugging set in /etc/pam.d/samba:
         *      auth required /lib/security/pam_pwdb.so nullok shadow audit
         */
        
-       DEBUG(4,("PAM: Authenticate User: %s\n", user));
-       pam_error = pam_authenticate(pamh, PAM_SILENT); /* Can we authenticate user? */
+       DEBUG(4,("smb_pam_auth: PAM: Authenticate User: %s\n", user));
+       pam_error = pam_authenticate(pamh, PAM_SILENT | lp_null_passwords() ? 0 : PAM_DISALLOW_NULL_AUTHTOK);
        switch( pam_error ){
                case PAM_AUTH_ERR:
-                       DEBUG(2, ("PAM: Athentication Error\n"));
+                       DEBUG(2, ("smb_pam_auth: PAM: Athentication Error for user %s\n", user));
+                       nt_status = NT_STATUS_WRONG_PASSWORD;
                        break;
                case PAM_CRED_INSUFFICIENT:
-                       DEBUG(2, ("PAM: Insufficient Credentials\n"));
+                       DEBUG(2, ("smb_pam_auth: PAM: Insufficient Credentials for user %s\n", user));
+                       nt_status = NT_STATUS_INSUFFICIENT_LOGON_INFO;
                        break;
                case PAM_AUTHINFO_UNAVAIL:
-                       DEBUG(2, ("PAM: Authentication Information Unavailable\n"));
+                       DEBUG(2, ("smb_pam_auth: PAM: Authentication Information Unavailable for user %s\n", user));
+                       nt_status = NT_STATUS_LOGON_FAILURE;
                        break;
                case PAM_USER_UNKNOWN:
-                       DEBUG(2, ("PAM: Username NOT known to Authentication system\n"));
+                       DEBUG(2, ("smb_pam_auth: PAM: Username %s NOT known to Authentication system\n", user));
+                       nt_status = NT_STATUS_NO_SUCH_USER;
                        break;
                case PAM_MAXTRIES:
-                       DEBUG(2, ("PAM: One or more authentication modules reports user limit exceeeded\n"));
+                       DEBUG(2, ("smb_pam_auth: PAM: One or more authentication modules reports user limit for user %s exceeeded\n", user));
+                       nt_status = NT_STATUS_REMOTE_SESSION_LIMIT;
                        break;
                case PAM_ABORT:
-                       DEBUG(0, ("PAM: One or more PAM modules failed to load\n"));
+                       DEBUG(0, ("smb_pam_auth: PAM: One or more PAM modules failed to load for user %s\n", user));
+                       nt_status = NT_STATUS_LOGON_FAILURE;
+                       break;
+               case PAM_SUCCESS:
+                       DEBUG(4, ("smb_pam_auth: PAM: User %s Authenticated OK\n", user));
+                       nt_status = NT_STATUS_NOPROBLEMO;
                        break;
-               case PAM_SUCCESS:
-                       DEBUG(4, ("PAM: User %s Authenticated OK\n", user));
-                       break;
                default:
-                       DEBUG(0, ("PAM: UNKNOWN ERROR while authenticating user %s\n", user));
-       }
-       if(!smb_pam_error_handler(pamh, pam_error, "Authentication Failure", 2)) {
-               smb_pam_end(pamh);
-               return False;
+                       DEBUG(0, ("smb_pam_auth: PAM: UNKNOWN ERROR while authenticating user %s\n", user));
+                       nt_status = NT_STATUS_LOGON_FAILURE;
+                       break;
        }
-       /* If this point is reached, the user has been authenticated. */
-       return (True);
+
+       smb_pam_nt_status_error_handler(pamh, pam_error, "Authentication Failure", 2, &nt_status);
+       return nt_status;
 }
 
 /* 
  * PAM Account Handler
  */
-static BOOL smb_pam_account(pam_handle_t *pamh, char * user, char * password, BOOL pam_auth)
+static uint32 smb_pam_account(pam_handle_t *pamh, char * user)
 {
        int pam_error;
+       uint32 nt_status = NT_STATUS_ACCOUNT_DISABLED;
 
-       DEBUG(4,("PAM: Account Management for User: %s\n", user));
+       DEBUG(4,("smb_pam_account: PAM: Account Management for User: %s\n", user));
        pam_error = pam_acct_mgmt(pamh, PAM_SILENT); /* Is user account enabled? */
        switch( pam_error ) {
                case PAM_AUTHTOK_EXPIRED:
-                       DEBUG(2, ("PAM: User is valid but password is expired\n"));
+                       DEBUG(2, ("smb_pam_account: PAM: User %s is valid but password is expired\n", user));
+                       nt_status = NT_STATUS_PASSWORD_EXPIRED;
                        break;
                case PAM_ACCT_EXPIRED:
-                       DEBUG(2, ("PAM: User no longer permitted to access system\n"));
+                       DEBUG(2, ("smb_pam_account: PAM: User %s no longer permitted to access system\n", user));
+                       nt_status = NT_STATUS_ACCOUNT_EXPIRED;
                        break;
                case PAM_AUTH_ERR:
-                       DEBUG(2, ("PAM: There was an authentication error\n"));
+                       DEBUG(2, ("smb_pam_account: PAM: There was an authentication error for user %s\n", user));
+                       nt_status = NT_STATUS_LOGON_FAILURE;
                        break;
                case PAM_PERM_DENIED:
-                       DEBUG(0, ("PAM: User is NOT permitted to access system at this time\n"));
+                       DEBUG(0, ("smb_pam_account: PAM: User %s is NOT permitted to access system at this time\n", user));
+                       nt_status = NT_STATUS_ACCOUNT_RESTRICTION;
                        break;
                case PAM_USER_UNKNOWN:
-                       DEBUG(0, ("PAM: User \"%s\" is NOT known to account management\n", user));
+                       DEBUG(0, ("smb_pam_account: PAM: User \"%s\" is NOT known to account management\n", user));
+                       nt_status = NT_STATUS_NO_SUCH_USER;
+                       break;
+               case PAM_SUCCESS:
+                       DEBUG(4, ("smb_pam_account: PAM: Account OK for User: %s\n", user));
+                       nt_status = NT_STATUS_NOPROBLEMO;
                        break;
-               case PAM_SUCCESS:
-                       DEBUG(4, ("PAM: Account OK for User: %s\n", user));
-                       break;
                default:
-                       DEBUG(0, ("PAM: UNKNOWN ERROR for User: %s\n", user));
-       }
-       if(!smb_pam_error_handler(pamh, pam_error, "Account Check Failed", 2)) {
-               smb_pam_end(pamh);
-               return False;
+                       nt_status = NT_STATUS_ACCOUNT_DISABLED;
+                       DEBUG(0, ("smb_pam_account: PAM: UNKNOWN PAM ERROR (%d) during Account Management for User: %s\n", pam_error, user));
+                       break;
        }
 
-       /* Skip the pam_setcred() call if we didn't use pam_authenticate()
-          for authentication -- it's an error to call pam_setcred without
-          calling pam_authenticate first */
-       if (!pam_auth) {
-               DEBUG(4, ("PAM: Skipping setcred for user: %s (using encrypted passwords)\n", user));
-               return True;
-       }
+       smb_pam_nt_status_error_handler(pamh, pam_error, "Account Check Failed", 2, &nt_status);
+       return nt_status;
+}
+
+/*
+ * PAM Credential Setting
+ */
+
+static uint32 smb_pam_setcred(pam_handle_t *pamh, char * user)
+{
+       int pam_error;
+       uint32 nt_status = NT_STATUS_NO_TOKEN;
 
        /*
         * This will allow samba to aquire a kerberos token. And, when
@@ -291,32 +453,34 @@ static BOOL smb_pam_account(pam_handle_t *pamh, char * user, char * password, BO
        pam_error = pam_setcred(pamh, (PAM_ESTABLISH_CRED|PAM_SILENT)); 
        switch( pam_error ) {
                case PAM_CRED_UNAVAIL:
-                       DEBUG(0, ("PAM: Credentials not found for user:%s", user ));
+                       DEBUG(0, ("smb_pam_setcred: PAM: Credentials not found for user:%s\n", user ));
+                        nt_status = NT_STATUS_NO_TOKEN;
                        break;
                case PAM_CRED_EXPIRED:
-                       DEBUG(0, ("PAM: Credentials for user: \"%s\" EXPIRED!", user ));
+                       DEBUG(0, ("smb_pam_setcred: PAM: Credentials for user: \"%s\" EXPIRED!\n", user ));
+                       nt_status = NT_STATUS_PASSWORD_EXPIRED;
                        break;
                case PAM_USER_UNKNOWN:
-                       DEBUG(0, ("PAM: User: \"%s\" is NOT known so can not set credentials!", user ));
+                       DEBUG(0, ("smb_pam_setcred: PAM: User: \"%s\" is NOT known so can not set credentials!\n", user ));
+                       nt_status = NT_STATUS_NO_SUCH_USER;
                        break;
                case PAM_CRED_ERR:
-                       DEBUG(0, ("PAM: Unknown setcredentials error - unable to set credentials for %s", user ));
+                       DEBUG(0, ("smb_pam_setcred: PAM: Unknown setcredentials error - unable to set credentials for %s\n", user ));
+                       nt_status = NT_STATUS_LOGON_FAILURE;
+                       break;
+               case PAM_SUCCESS:
+                       DEBUG(4, ("smb_pam_setcred: PAM: SetCredentials OK for User: %s\n", user));
+                       nt_status = NT_STATUS_NOPROBLEMO;
                        break;
-               case PAM_SUCCESS:
-                       DEBUG(4, ("PAM: SetCredentials OK for User: %s\n", user));
-                       break;
                default:
-                       DEBUG(0, ("PAM: Error Condition Unknown in pam_setcred function call!"));
-       }
-       if(!smb_pam_error_handler(pamh, pam_error, "Set Credential Failure", 2)) {
-               smb_pam_end(pamh);
-               return False;
+                       DEBUG(0, ("smb_pam_setcred: PAM: UNKNOWN PAM ERROR (%d) during SetCredentials for User: %s\n", pam_error, user));
+                       nt_status = NT_STATUS_NO_TOKEN;
+                       break;
        }
-       
-       /* If this point is reached, the user has been authenticated. */
-       return (True);
-}
 
+       smb_pam_nt_status_error_handler(pamh, pam_error, "Set Credential Failure", 2, &nt_status);
+       return nt_status;
+}
 
 /*
  * PAM Internal Session Handler
@@ -325,11 +489,8 @@ static BOOL smb_internal_pam_session(pam_handle_t *pamh, char *user, char *tty,
 {
        int pam_error;
 
-       PAM_password = NULL;
-       PAM_username = user;
-
 #ifdef PAM_TTY
-       DEBUG(4,("PAM: tty set to: %s\n", tty));
+       DEBUG(4,("smb_internal_pam_session: PAM: tty set to: %s\n", tty));
        pam_error = pam_set_item(pamh, PAM_TTY, tty);
        if (!smb_pam_error_handler(pamh, pam_error, "set tty failed", 0))
                return False;
@@ -340,77 +501,156 @@ static BOOL smb_internal_pam_session(pam_handle_t *pamh, char *user, char *tty,
                if (!smb_pam_error_handler(pamh, pam_error, "session setup failed", 0))
                        return False;
        } else {
-               pam_error = pam_close_session(pamh, PAM_SILENT);
+               pam_setcred(pamh, (PAM_DELETE_CRED|PAM_SILENT)); /* We don't care if this fails */
+               pam_error = pam_close_session(pamh, PAM_SILENT); /* This will probably pick up the error anyway */
                if (!smb_pam_error_handler(pamh, pam_error, "session close failed", 0))
                        return False;
        }
        return (True);
 }
 
+/*
+ * Internal PAM Password Changer.
+ */
+
+static BOOL smb_pam_chauthtok(pam_handle_t *pamh, char * user)
+{
+       int pam_error;
+
+       DEBUG(4,("smb_pam_chauthtok: PAM: Password Change for User: %s\n", user));
+
+       pam_error = pam_chauthtok(pamh, PAM_SILENT); /* Change Password */
+
+       switch( pam_error ) {
+       case PAM_AUTHTOK_ERR:
+               DEBUG(2, ("PAM: unable to obtain the new authentication token - is password to weak?\n"));
+               break;
+       case PAM_AUTHTOK_RECOVER_ERR:
+               DEBUG(2, ("PAM: unable to obtain the old authentication token - was the old password wrong?.\n"));
+               break;
+       case PAM_AUTHTOK_LOCK_BUSY:
+               DEBUG(2, ("PAM: unable to change the authentication token since it is currently locked.\n"));
+               break;
+       case PAM_AUTHTOK_DISABLE_AGING:
+               DEBUG(2, ("PAM: Authentication token aging has been disabled.\n"));
+               break;
+       case PAM_PERM_DENIED:
+               DEBUG(0, ("PAM: Permission denied.\n"));
+               break;
+       case PAM_TRY_AGAIN:
+               DEBUG(0, ("PAM: Could not update all authentication token(s). No authentication tokens were updated.\n"));
+               break;
+       case PAM_USER_UNKNOWN:
+               DEBUG(0, ("PAM: User not known to PAM\n"));
+               break;
+       case PAM_SUCCESS:
+               DEBUG(4, ("PAM: Account OK for User: %s\n", user));
+               break;
+       default:
+               DEBUG(0, ("PAM: UNKNOWN PAM ERROR (%d) for User: %s\n", pam_error, user));
+       }
+       if(!smb_pam_error_handler(pamh, pam_error, "Password Change Failed", 2)) {
+               return False;
+       }
+
+       /* If this point is reached, the password has changed. */
+       return True;
+}
+
 /*
  * PAM Externally accessible Session handler
  */
 
-BOOL smb_pam_session(BOOL flag, const char *in_user, char *tty, char *rhost)
+BOOL smb_pam_claim_session(char *user, char *tty, char *rhost)
 {
        pam_handle_t *pamh = NULL;
-       char * user;
+       struct pam_conv *pconv = NULL;
 
        /* Ignore PAM if told to. */
 
        if (!lp_obey_pam_restrictions())
                return True;
 
-       user = strdup(in_user);
-       if ( user == NULL ) {
-               DEBUG(0, ("PAM: PAM_session Malloc Failed!\n"));
+       if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
                return False;
-       }
 
-       if (!smb_pam_start(&pamh, user, rhost)) {
+       if (!smb_pam_start(&pamh, user, rhost, pconv))
                return False;
-       }
 
-       if (!smb_internal_pam_session(pamh, user, tty, flag)) {
-               smb_pam_end(pamh);
+       if (!smb_internal_pam_session(pamh, user, tty, True)) {
+               smb_pam_end(pamh, pconv);
                return False;
        }
-       return smb_pam_end(pamh);
+
+       return smb_pam_end(pamh, pconv);
 }
 
 /*
- * PAM Externally accessible Account handler
+ * PAM Externally accessible Session handler
  */
-BOOL smb_pam_accountcheck(char * user)
+
+BOOL smb_pam_close_session(char *user, char *tty, char *rhost)
 {
        pam_handle_t *pamh = NULL;
-
-       PAM_username = user;
-       PAM_password = NULL;
+       struct pam_conv *pconv = NULL;
 
        /* Ignore PAM if told to. */
 
        if (!lp_obey_pam_restrictions())
                return True;
 
-       if( smb_pam_start(&pamh, user, NULL)) {
-               if ( smb_pam_account(pamh, user, NULL, False)) {
-                       return( smb_pam_end(pamh));
-               }
+       if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
+               return False;
+
+       if (!smb_pam_start(&pamh, user, rhost, pconv))
+               return False;
+
+       if (!smb_internal_pam_session(pamh, user, tty, False)) {
+               smb_pam_end(pamh, pconv);
+               return False;
        }
-       DEBUG(0, ("PAM: Account Validation Failed - Rejecting User!\n"));
-       return( False );
+
+       return smb_pam_end(pamh, pconv);
 }
 
 /*
- * PAM Password Validation Suite
+ * PAM Externally accessible Account handler
  */
-BOOL smb_pam_passcheck(char * user, char * password)
+
+uint32 smb_pam_accountcheck(char * user)
 {
+       uint32 nt_status = NT_STATUS_ACCOUNT_DISABLED;
        pam_handle_t *pamh = NULL;
+       struct pam_conv *pconv = NULL;
 
-       PAM_username = user;
-       PAM_password = password;
+       /* Ignore PAM if told to. */
+
+       if (!lp_obey_pam_restrictions())
+               return NT_STATUS_NOPROBLEMO;
+
+       if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
+               return False;
+
+       if (!smb_pam_start(&pamh, user, NULL, pconv))
+               return NT_STATUS_ACCOUNT_DISABLED;
+
+       if ((nt_status = smb_pam_account(pamh, user)) != NT_STATUS_NOPROBLEMO)
+               DEBUG(0, ("smb_pam_accountcheck: PAM: Account Validation Failed - Rejecting User %s!\n", user));
+
+       smb_pam_end(pamh, pconv);
+       return nt_status;
+}
+
+/*
+ * PAM Password Validation Suite
+ */
+
+uint32 smb_pam_passcheck(char * user, char * password)
+{
+       pam_handle_t *pamh = NULL;
+       uint32 nt_status = NT_STATUS_LOGON_FAILURE;
+       struct pam_conv *pconv = NULL;
 
        /*
         * Note we can't ignore PAM here as this is the only
@@ -418,23 +658,76 @@ BOOL smb_pam_passcheck(char * user, char * password)
         * compiled --with-pam.
         */
 
-       if( smb_pam_start(&pamh, user, NULL)) {
-               if ( smb_pam_auth(pamh, user, password)) {
-                       if ( smb_pam_account(pamh, user, password, True)) {
-                               return( smb_pam_end(pamh));
-                       }
-               }
+       if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, password, NULL)) == NULL)
+               return False;
+
+       if (!smb_pam_start(&pamh, user, NULL, NULL))
+               return NT_STATUS_LOGON_FAILURE;
+
+       if ((nt_status = smb_pam_auth(pamh, user)) != NT_STATUS_NOPROBLEMO) {
+               DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_auth failed - Rejecting User %s !\n", user));
+               smb_pam_end(pamh, pconv);
+               return nt_status;
+       }
+
+       if ((nt_status = smb_pam_account(pamh, user)) != NT_STATUS_NOPROBLEMO) {
+               DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_account failed - Rejecting User %s !\n", user));
+               smb_pam_end(pamh, pconv);
+               return nt_status;
+       }
+
+       if ((nt_status = smb_pam_setcred(pamh, user)) != NT_STATUS_NOPROBLEMO) {
+               DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_setcred failed - Rejecting User %s !\n", user));
+               smb_pam_end(pamh, pconv);
+               return nt_status;
        }
-       DEBUG(0, ("PAM: System Validation Failed - Rejecting User!\n"));
-       return( False );
+
+       smb_pam_end(pamh, pconv);
+       return nt_status;
+}
+
+/*
+ * PAM Password Change Suite
+ */
+
+BOOL smb_pam_passchange(char * user, char * oldpassword, char * newpassword)
+{
+       /* Appropriate quantities of root should be obtained BEFORE calling this function */
+       struct pam_conv *pconv = NULL;
+       pam_handle_t *pamh = NULL;
+
+       if ((pconv = smb_setup_pam_conv(smb_pam_passchange_conv, user, oldpassword, newpassword)) == NULL)
+               return False;
+
+       if(!smb_pam_start(&pamh, user, NULL, pconv))
+               return False;
+
+       if (!smb_pam_chauthtok(pamh, user)) {
+               DEBUG(0, ("smb_pam_passchange: PAM: Password Change Failed for user %s!\n", user));
+               smb_pam_end(pamh, pconv);
+               return False;
+       }
+
+       return smb_pam_end(pamh, pconv);
 }
 
 #else
 
 /* If PAM not used, no PAM restrictions on accounts. */
- BOOL smb_pam_accountcheck(char * user)
+ uint32 smb_pam_accountcheck(char * user)
+{
+       return NT_STATUS_NOPROBLEMO;
+}
+
+/* If PAM not used, also no PAM restrictions on sessions. */
+ BOOL smb_pam_claim_session(const char *user, char *tty, char *rhost)
 {
        return True;
 }
 
+/* If PAM not used, also no PAM restrictions on sessions. */
+ BOOL smb_pam_close_session(const char *in_user, char *tty, char *rhost)
+{
+       return True;
+}
 #endif /* WITH_PAM */