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-rw-r--r--source4/pam_smbpass/support.c637
1 files changed, 637 insertions, 0 deletions
diff --git a/source4/pam_smbpass/support.c b/source4/pam_smbpass/support.c
new file mode 100644
index 0000000000..11de306d13
--- /dev/null
+++ b/source4/pam_smbpass/support.c
@@ -0,0 +1,637 @@
+ /* Unix NT password database implementation, version 0.6.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 675
+ * Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+ #include "includes.h"
+ #include "general.h"
+
+ #include "support.h"
+
+
+ #define _pam_overwrite(x) \
+ do { \
+ register char *__xx__; \
+ if ((__xx__=(x))) \
+ while (*__xx__) \
+ *__xx__++ = '\0'; \
+ } while (0)
+
+ /*
+ * Don't just free it, forget it too.
+ */
+
+ #define _pam_drop(X) \
+ do { \
+ if (X) { \
+ free(X); \
+ X=NULL; \
+ } \
+ } while (0)
+
+ #define _pam_drop_reply(/* struct pam_response * */ reply, /* int */ replies) \
+ do { \
+ int reply_i; \
+ \
+ for (reply_i=0; reply_i<replies; ++reply_i) { \
+ if (reply[reply_i].resp) { \
+ _pam_overwrite(reply[reply_i].resp); \
+ free(reply[reply_i].resp); \
+ } \
+ } \
+ if (reply) \
+ free(reply); \
+ } while (0)
+
+
+ int converse(pam_handle_t *, int, int, struct pam_message **,
+ struct pam_response **);
+ int make_remark(pam_handle_t *, unsigned int, int, const char *);
+ void _cleanup(pam_handle_t *, void *, int);
+ char *_pam_delete(register char *);
+
+ /* default configuration file location */
+
+ char *servicesf = dyn_CONFIGFILE;
+
+ /* syslogging function for errors and other information */
+
+ void _log_err( int err, const char *format, ... )
+ {
+ va_list args;
+
+ va_start( args, format );
+ openlog( "PAM_smbpass", LOG_CONS | LOG_PID, LOG_AUTH );
+ vsyslog( err, format, args );
+ va_end( args );
+ closelog();
+ }
+
+ /* this is a front-end for module-application conversations */
+
+ int converse( pam_handle_t * pamh, int ctrl, int nargs
+ , struct pam_message **message
+ , struct pam_response **response )
+ {
+ int retval;
+ struct pam_conv *conv;
+
+ retval = pam_get_item(pamh, PAM_CONV, (const void **) &conv);
+ if (retval == PAM_SUCCESS) {
+
+ retval = conv->conv(nargs, (const struct pam_message **) message
+ ,response, conv->appdata_ptr);
+
+ if (retval != PAM_SUCCESS && on(SMB_DEBUG, ctrl)) {
+ _log_err(LOG_DEBUG, "conversation failure [%s]"
+ ,pam_strerror(pamh, retval));
+ }
+ } else {
+ _log_err(LOG_ERR, "couldn't obtain coversation function [%s]"
+ ,pam_strerror(pamh, retval));
+ }
+
+ return retval; /* propagate error status */
+ }
+
+ int make_remark( pam_handle_t * pamh, unsigned int ctrl
+ , int type, const char *text )
+ {
+ if (off(SMB__QUIET, ctrl)) {
+ struct pam_message *pmsg[1], msg[1];
+ struct pam_response *resp;
+
+ pmsg[0] = &msg[0];
+ msg[0].msg = text;
+ msg[0].msg_style = type;
+ resp = NULL;
+
+ return converse(pamh, ctrl, 1, pmsg, &resp);
+ }
+ return PAM_SUCCESS;
+ }
+
+
+ /* set the control flags for the SMB module. */
+
+int set_ctrl( int flags, int argc, const char **argv )
+{
+ int i = 0;
+ const char *service_file = dyn_CONFIGFILE;
+ unsigned int ctrl;
+
+ ctrl = SMB_DEFAULTS; /* the default selection of options */
+
+ /* set some flags manually */
+
+ /* A good, sane default (matches Samba's behavior). */
+ set( SMB__NONULL, ctrl );
+
+ /* initialize service file location */
+ service_file=servicesf;
+
+ if (flags & PAM_SILENT) {
+ set( SMB__QUIET, ctrl );
+ }
+
+ /* Run through the arguments once, looking for an alternate smb config
+ file location */
+ while (i < argc) {
+ int j;
+
+ for (j = 0; j < SMB_CTRLS_; ++j) {
+ if (smb_args[j].token
+ && !strncmp(argv[i], smb_args[j].token, strlen(smb_args[j].token)))
+ {
+ break;
+ }
+ }
+
+ if (j == SMB_CONF_FILE) {
+ service_file = argv[i] + 8;
+ }
+ i++;
+ }
+
+ /* Read some options from the Samba config. Can be overridden by
+ the PAM config. */
+ if(lp_load(service_file,True,False,False) == False) {
+ _log_err( LOG_ERR, "Error loading service file %s", service_file );
+ }
+
+ secrets_init();
+
+ if (lp_null_passwords()) {
+ set( SMB__NULLOK, ctrl );
+ }
+
+ /* now parse the rest of the arguments to this module */
+
+ while (argc-- > 0) {
+ int j;
+
+ for (j = 0; j < SMB_CTRLS_; ++j) {
+ if (smb_args[j].token
+ && !strncmp(*argv, smb_args[j].token, strlen(smb_args[j].token)))
+ {
+ break;
+ }
+ }
+
+ if (j >= SMB_CTRLS_) {
+ _log_err( LOG_ERR, "unrecognized option [%s]", *argv );
+ } else {
+ ctrl &= smb_args[j].mask; /* for turning things off */
+ ctrl |= smb_args[j].flag; /* for turning things on */
+ }
+
+ ++argv; /* step to next argument */
+ }
+
+ /* auditing is a more sensitive version of debug */
+
+ if (on( SMB_AUDIT, ctrl )) {
+ set( SMB_DEBUG, ctrl );
+ }
+ /* return the set of flags */
+
+ return ctrl;
+}
+
+/* use this to free strings. ESPECIALLY password strings */
+
+char * _pam_delete( register char *xx )
+{
+ _pam_overwrite( xx );
+ _pam_drop( xx );
+ return NULL;
+}
+
+void _cleanup( pam_handle_t * pamh, void *x, int error_status )
+{
+ x = _pam_delete( (char *) x );
+}
+
+/* JHT
+ *
+ * Safe duplication of character strings. "Paranoid"; don't leave
+ * evidence of old token around for later stack analysis.
+ *
+ */
+char * smbpXstrDup( const char *x )
+{
+ register char *new = NULL;
+
+ if (x != NULL) {
+ register int i;
+
+ for (i = 0; x[i]; ++i); /* length of string */
+ if ((new = malloc(++i)) == NULL) {
+ i = 0;
+ _log_err( LOG_CRIT, "out of memory in smbpXstrDup" );
+ } else {
+ while (i-- > 0) {
+ new[i] = x[i];
+ }
+ }
+ x = NULL;
+ }
+ return new; /* return the duplicate or NULL on error */
+}
+
+/* ************************************************************** *
+ * Useful non-trivial functions *
+ * ************************************************************** */
+
+void _cleanup_failures( pam_handle_t * pamh, void *fl, int err )
+{
+ int quiet;
+ const char *service = NULL;
+ struct _pam_failed_auth *failure;
+
+#ifdef PAM_DATA_SILENT
+ quiet = err & PAM_DATA_SILENT; /* should we log something? */
+#else
+ quiet = 0;
+#endif
+#ifdef PAM_DATA_REPLACE
+ err &= PAM_DATA_REPLACE; /* are we just replacing data? */
+#endif
+ failure = (struct _pam_failed_auth *) fl;
+
+ if (failure != NULL) {
+
+#ifdef PAM_DATA_SILENT
+ if (!quiet && !err) { /* under advisement from Sun,may go away */
+#else
+ if (!quiet) { /* under advisement from Sun,may go away */
+#endif
+
+ /* log the number of authentication failures */
+ if (failure->count != 0) {
+ pam_get_item( pamh, PAM_SERVICE, (const void **) &service );
+ _log_err( LOG_NOTICE
+ , "%d authentication %s "
+ "from %s for service %s as %s(%d)"
+ , failure->count
+ , failure->count == 1 ? "failure" : "failures"
+ , failure->agent
+ , service == NULL ? "**unknown**" : service
+ , failure->user, failure->id );
+ if (failure->count > SMB_MAX_RETRIES) {
+ _log_err( LOG_ALERT
+ , "service(%s) ignoring max retries; %d > %d"
+ , service == NULL ? "**unknown**" : service
+ , failure->count
+ , SMB_MAX_RETRIES );
+ }
+ }
+ }
+ _pam_delete( failure->agent ); /* tidy up */
+ _pam_delete( failure->user ); /* tidy up */
+ SAFE_FREE( failure );
+ }
+}
+
+int _smb_verify_password( pam_handle_t * pamh, SAM_ACCOUNT *sampass,
+ const char *p, unsigned int ctrl )
+{
+ uchar hash_pass[16];
+ uchar lm_pw[16];
+ uchar nt_pw[16];
+ int retval = PAM_AUTH_ERR;
+ char *data_name;
+ const char *name;
+
+ if (!sampass)
+ return PAM_ABORT;
+
+ name = pdb_get_username(sampass);
+
+#ifdef HAVE_PAM_FAIL_DELAY
+ if (off( SMB_NODELAY, ctrl )) {
+ (void) pam_fail_delay( pamh, 1000000 ); /* 1 sec delay for on failure */
+ }
+#endif
+
+ if (!pdb_get_lanman_passwd(sampass))
+ {
+ _log_err( LOG_DEBUG, "user %s has null SMB password"
+ , name );
+
+ if (off( SMB__NONULL, ctrl )
+ && (pdb_get_acct_ctrl(sampass) & ACB_PWNOTREQ))
+ { /* this means we've succeeded */
+ return PAM_SUCCESS;
+ } else {
+ const char *service;
+
+ pam_get_item( pamh, PAM_SERVICE, (const void **)&service );
+ _log_err( LOG_NOTICE
+ , "failed auth request by %s for service %s as %s(%d)"
+ , uidtoname( getuid() )
+ , service ? service : "**unknown**", name
+ , pdb_get_uid(sampass) );
+ return PAM_AUTH_ERR;
+ }
+ }
+
+ data_name = (char *) malloc( sizeof(FAIL_PREFIX) + strlen( name ));
+ if (data_name == NULL) {
+ _log_err( LOG_CRIT, "no memory for data-name" );
+ }
+ strncpy( data_name, FAIL_PREFIX, sizeof(FAIL_PREFIX) );
+ strncpy( data_name + sizeof(FAIL_PREFIX) - 1, name, strlen( name ) + 1 );
+
+ /*
+ * The password we were given wasn't an encrypted password, or it
+ * didn't match the one we have. We encrypt the password now and try
+ * again.
+ */
+
+ nt_lm_owf_gen(p, nt_pw, lm_pw);
+
+ /* the moment of truth -- do we agree with the password? */
+
+ if (!memcmp( nt_pw, pdb_get_nt_passwd(sampass), 16 )) {
+
+ retval = PAM_SUCCESS;
+ if (data_name) { /* reset failures */
+ pam_set_data(pamh, data_name, NULL, _cleanup_failures);
+ }
+ } else {
+
+ const char *service;
+
+ pam_get_item( pamh, PAM_SERVICE, (const void **)&service );
+
+ if (data_name != NULL) {
+ struct _pam_failed_auth *new = NULL;
+ const struct _pam_failed_auth *old = NULL;
+
+ /* get a failure recorder */
+
+ new = (struct _pam_failed_auth *)
+ malloc( sizeof(struct _pam_failed_auth) );
+
+ if (new != NULL) {
+
+ /* any previous failures for this user ? */
+ pam_get_data(pamh, data_name, (const void **) &old);
+
+ if (old != NULL) {
+ new->count = old->count + 1;
+ if (new->count >= SMB_MAX_RETRIES) {
+ retval = PAM_MAXTRIES;
+ }
+ } else {
+ _log_err( LOG_NOTICE
+ , "failed auth request by %s for service %s as %s(%d)"
+ , uidtoname( getuid() )
+ , service ? service : "**unknown**", name
+ , pdb_get_uid(sampass) );
+ new->count = 1;
+ }
+ new->user = smbpXstrDup( name );
+ new->id = pdb_get_uid(sampass);
+ new->agent = smbpXstrDup( uidtoname( getuid() ) );
+ pam_set_data( pamh, data_name, new, _cleanup_failures );
+
+ } else {
+ _log_err( LOG_CRIT, "no memory for failure recorder" );
+ _log_err( LOG_NOTICE
+ , "failed auth request by %s for service %s as %s(%d)"
+ , uidtoname( getuid() )
+ , service ? service : "**unknown**", name
+ , pdb_get_uid(sampass) );
+ }
+ } else {
+ _log_err( LOG_NOTICE
+ , "failed auth request by %s for service %s as %s(%d)"
+ , uidtoname( getuid() )
+ , service ? service : "**unknown**", name
+ , pdb_get_uid(sampass) );
+ retval = PAM_AUTH_ERR;
+ }
+ }
+
+ _pam_delete( data_name );
+
+ return retval;
+}
+
+
+/*
+ * _smb_blankpasswd() is a quick check for a blank password
+ *
+ * returns TRUE if user does not have a password
+ * - to avoid prompting for one in such cases (CG)
+ */
+
+int _smb_blankpasswd( unsigned int ctrl, SAM_ACCOUNT *sampass )
+{
+ int retval;
+
+ /*
+ * This function does not have to be too smart if something goes
+ * wrong, return FALSE and let this case to be treated somewhere
+ * else (CG)
+ */
+
+ if (on( SMB__NONULL, ctrl ))
+ return 0; /* will fail but don't let on yet */
+
+ if (pdb_get_lanman_passwd(sampass) == NULL)
+ retval = 1;
+ else
+ retval = 0;
+
+ return retval;
+}
+
+/*
+ * obtain a password from the user
+ */
+
+int _smb_read_password( pam_handle_t * pamh, unsigned int ctrl,
+ const char *comment, const char *prompt1,
+ const char *prompt2, const char *data_name, char **pass )
+{
+ int authtok_flag;
+ int retval;
+ char *item = NULL;
+ char *token;
+
+ struct pam_message msg[3], *pmsg[3];
+ struct pam_response *resp;
+ int i, expect;
+
+
+ /* make sure nothing inappropriate gets returned */
+
+ *pass = token = NULL;
+
+ /* which authentication token are we getting? */
+
+ authtok_flag = on(SMB__OLD_PASSWD, ctrl) ? PAM_OLDAUTHTOK : PAM_AUTHTOK;
+
+ /* should we obtain the password from a PAM item ? */
+
+ if (on(SMB_TRY_FIRST_PASS, ctrl) || on(SMB_USE_FIRST_PASS, ctrl)) {
+ retval = pam_get_item( pamh, authtok_flag, (const void **) &item );
+ if (retval != PAM_SUCCESS) {
+ /* very strange. */
+ _log_err( LOG_ALERT
+ , "pam_get_item returned error to smb_read_password" );
+ return retval;
+ } else if (item != NULL) { /* we have a password! */
+ *pass = item;
+ item = NULL;
+ return PAM_SUCCESS;
+ } else if (on( SMB_USE_FIRST_PASS, ctrl )) {
+ return PAM_AUTHTOK_RECOVER_ERR; /* didn't work */
+ } else if (on( SMB_USE_AUTHTOK, ctrl )
+ && off( SMB__OLD_PASSWD, ctrl ))
+ {
+ return PAM_AUTHTOK_RECOVER_ERR;
+ }
+ }
+
+ /*
+ * getting here implies we will have to get the password from the
+ * user directly.
+ */
+
+ /* prepare to converse */
+ if (comment != NULL && off(SMB__QUIET, ctrl)) {
+ pmsg[0] = &msg[0];
+ msg[0].msg_style = PAM_TEXT_INFO;
+ msg[0].msg = comment;
+ i = 1;
+ } else {
+ i = 0;
+ }
+
+ pmsg[i] = &msg[i];
+ msg[i].msg_style = PAM_PROMPT_ECHO_OFF;
+ msg[i++].msg = prompt1;
+
+ if (prompt2 != NULL) {
+ pmsg[i] = &msg[i];
+ msg[i].msg_style = PAM_PROMPT_ECHO_OFF;
+ msg[i++].msg = prompt2;
+ expect = 2;
+ } else
+ expect = 1;
+
+ resp = NULL;
+
+ retval = converse( pamh, ctrl, i, pmsg, &resp );
+
+ if (resp != NULL) {
+ int j = comment ? 1 : 0;
+ /* interpret the response */
+
+ if (retval == PAM_SUCCESS) { /* a good conversation */
+
+ token = smbpXstrDup(resp[j++].resp);
+ if (token != NULL) {
+ if (expect == 2) {
+ /* verify that password entered correctly */
+ if (!resp[j].resp || strcmp( token, resp[j].resp )) {
+ _pam_delete( token );
+ retval = PAM_AUTHTOK_RECOVER_ERR;
+ make_remark( pamh, ctrl, PAM_ERROR_MSG
+ , MISTYPED_PASS );
+ }
+ }
+ } else {
+ _log_err(LOG_NOTICE, "could not recover authentication token");
+ }
+ }
+
+ /* tidy up */
+ _pam_drop_reply( resp, expect );
+
+ } else {
+ retval = (retval == PAM_SUCCESS) ? PAM_AUTHTOK_RECOVER_ERR : retval;
+ }
+
+ if (retval != PAM_SUCCESS) {
+ if (on( SMB_DEBUG, ctrl ))
+ _log_err( LOG_DEBUG, "unable to obtain a password" );
+ return retval;
+ }
+ /* 'token' is the entered password */
+
+ if (off( SMB_NOT_SET_PASS, ctrl )) {
+
+ /* we store this password as an item */
+
+ retval = pam_set_item( pamh, authtok_flag, (const void *)token );
+ _pam_delete( token ); /* clean it up */
+ if (retval != PAM_SUCCESS
+ || (retval = pam_get_item( pamh, authtok_flag
+ ,(const void **)&item )) != PAM_SUCCESS)
+ {
+ _log_err( LOG_CRIT, "error manipulating password" );
+ return retval;
+ }
+ } else {
+ /*
+ * then store it as data specific to this module. pam_end()
+ * will arrange to clean it up.
+ */
+
+ retval = pam_set_data( pamh, data_name, (void *) token, _cleanup );
+ if (retval != PAM_SUCCESS
+ || (retval = pam_get_data( pamh, data_name, (const void **)&item ))
+ != PAM_SUCCESS)
+ {
+ _log_err( LOG_CRIT, "error manipulating password data [%s]"
+ , pam_strerror( pamh, retval ));
+ _pam_delete( token );
+ item = NULL;
+ return retval;
+ }
+ token = NULL; /* break link to password */
+ }
+
+ *pass = item;
+ item = NULL; /* break link to password */
+
+ return PAM_SUCCESS;
+}
+
+int _pam_smb_approve_pass(pam_handle_t * pamh,
+ unsigned int ctrl,
+ const char *pass_old,
+ const char *pass_new )
+{
+
+ /* Further checks should be handled through module stacking. -SRL */
+ if (pass_new == NULL || (pass_old && !strcmp( pass_old, pass_new )))
+ {
+ if (on(SMB_DEBUG, ctrl)) {
+ _log_err( LOG_DEBUG,
+ "passwd: bad authentication token (null or unchanged)" );
+ }
+ make_remark( pamh, ctrl, PAM_ERROR_MSG, pass_new == NULL ?
+ "No password supplied" : "Password unchanged" );
+ return PAM_AUTHTOK_ERR;
+ }
+
+ return PAM_SUCCESS;
+}