first public release of samba4 code

source/pam_smbpass/pam_smb_auth.c

@@ -0,0 +1,249 @@
+/* Unix NT password database implementation, version 0.7.5.
+ *
+ * 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.
+*/
+
+/* indicate the following groups are defined */
+#define PAM_SM_AUTH
+
+#include "includes.h"
+#include "debug.h"
+
+#ifndef LINUX
+
+/* This is only used in the Sun implementation. */
+#include <security/pam_appl.h>
+
+#endif  /* LINUX */
+
+#include <security/pam_modules.h>
+
+#include "general.h"
+
+#include "support.h"
+
+#define AUTH_RETURN						\
+do {								\
+	if(ret_data) {						\
+		*ret_data = retval;				\
+		pam_set_data( pamh, "smb_setcred_return"	\
+		              , (void *) ret_data, NULL );	\
+	}							\
+	return retval;						\
+} while (0)
+
+static int _smb_add_user(pam_handle_t *pamh, unsigned int ctrl,
+                         const char *name, SAM_ACCOUNT *sampass, BOOL exist);
+
+
+/*
+ * pam_sm_authenticate() authenticates users against the samba password file.
+ *
+ *	First, obtain the password from the user. Then use a
+ *      routine in 'support.c' to authenticate the user.
+ */
+
+#define _SMB_AUTHTOK  "-SMB-PASS"
+
+int pam_sm_authenticate(pam_handle_t *pamh, int flags,
+                        int argc, const char **argv)
+{
+    unsigned int ctrl;
+    int retval, *ret_data = NULL;
+    SAM_ACCOUNT *sampass = NULL;
+    extern BOOL in_client;
+    const char *name;
+    BOOL found;
+
+    /* Points to memory managed by the PAM library. Do not free. */
+    char *p = NULL;
+
+
+    /* Samba initialization. */
+    setup_logging("pam_smbpass",False);
+    in_client = True;
+
+    ctrl = set_ctrl(flags, argc, argv);
+
+    /* Get a few bytes so we can pass our return value to
+       pam_sm_setcred(). */
+    ret_data = malloc(sizeof(int));
+
+    /* get the username */
+    retval = pam_get_user( pamh, &name, "Username: " );
+    if ( retval != PAM_SUCCESS ) {
+        if (on( SMB_DEBUG, ctrl )) {
+	    _log_err(LOG_DEBUG, "auth: could not identify user");
+        }
+        AUTH_RETURN;
+    }
+    if (on( SMB_DEBUG, ctrl )) {
+        _log_err( LOG_DEBUG, "username [%s] obtained", name );
+    }
+
+    if (!initialize_password_db(True)) {
+        _log_err( LOG_ALERT, "Cannot access samba password database" );
+        retval = PAM_AUTHINFO_UNAVAIL;
+        AUTH_RETURN;
+    }
+
+    pdb_init_sam(&sampass);
+    
+    found = pdb_getsampwnam( sampass, name );
+
+    if (on( SMB_MIGRATE, ctrl )) {
+	retval = _smb_add_user(pamh, ctrl, name, sampass, found);
+	pdb_free_sam(&sampass);
+	AUTH_RETURN;
+    }
+
+    if (!found) {
+        _log_err(LOG_ALERT, "Failed to find entry for user %s.", name);
+        retval = PAM_USER_UNKNOWN;
+	pdb_free_sam(&sampass);
+	sampass = NULL;
+        AUTH_RETURN;
+    }
+   
+    /* if this user does not have a password... */
+
+    if (_smb_blankpasswd( ctrl, sampass )) {
+        pdb_free_sam(&sampass);
+        retval = PAM_SUCCESS;
+        AUTH_RETURN;
+    }
+
+    /* get this user's authentication token */
+
+    retval = _smb_read_password(pamh, ctrl, NULL, "Password: ", NULL, _SMB_AUTHTOK, &p);
+    if (retval != PAM_SUCCESS ) {
+	_log_err(LOG_CRIT, "auth: no password provided for [%s]"
+		 , name);
+        pdb_free_sam(&sampass);
+        AUTH_RETURN;
+    }
+
+    /* verify the password of this user */
+
+    retval = _smb_verify_password( pamh, sampass, p, ctrl );
+    pdb_free_sam(&sampass);
+    p = NULL;
+    AUTH_RETURN;
+}
+
+/*
+ * This function is for setting samba credentials.  If anyone comes up
+ * with any credentials they think should be set, let me know.
+ */
+
+int pam_sm_setcred(pam_handle_t *pamh, int flags,
+                   int argc, const char **argv)
+{
+    int retval, *pretval = NULL;
+
+    retval = PAM_SUCCESS;
+
+    pam_get_data(pamh, "smb_setcred_return", (const void **) &pretval);
+    if(pretval) {
+	retval = *pretval;
+	SAFE_FREE(pretval);
+    }
+    pam_set_data(pamh, "smb_setcred_return", NULL, NULL);
+
+    return retval;
+}
+
+
+/* Helper function for adding a user to the db. */
+static int _smb_add_user(pam_handle_t *pamh, unsigned int ctrl,
+                         const char *name, SAM_ACCOUNT *sampass, BOOL exist)
+{
+    pstring err_str;
+    pstring msg_str;
+    const char *pass = NULL;
+    int retval;
+
+    err_str[0] = '\0';
+    msg_str[0] = '\0';
+
+    /* Get the authtok; if we don't have one, silently fail. */
+    retval = pam_get_item( pamh, PAM_AUTHTOK, (const void **) &pass );
+
+    if (retval != PAM_SUCCESS) {
+	_log_err( LOG_ALERT
+	          , "pam_get_item returned error to pam_sm_authenticate" );
+	return PAM_AUTHTOK_RECOVER_ERR;
+    } else if (pass == NULL) {
+	return PAM_AUTHTOK_RECOVER_ERR;
+    }
+
+    /* Add the user to the db if they aren't already there. */
+   if (!exist) {
+	retval = local_password_change( name, LOCAL_ADD_USER,
+	                                 pass, err_str,
+	                                 sizeof(err_str),
+	                                 msg_str, sizeof(msg_str) );
+	if (!retval && *err_str)
+	{
+	    err_str[PSTRING_LEN-1] = '\0';
+	    make_remark( pamh, ctrl, PAM_ERROR_MSG, err_str );
+	}
+	else if (*msg_str)
+	{
+	    msg_str[PSTRING_LEN-1] = '\0';
+	    make_remark( pamh, ctrl, PAM_TEXT_INFO, msg_str );
+	}
+	pass = NULL;
+
+	return PAM_IGNORE;
+   }
+   else {
+    /* Change the user's password IFF it's null. */
+    if ((pdb_get_lanman_passwd(sampass) == NULL) && (pdb_get_acct_ctrl(sampass) & ACB_PWNOTREQ))
+    {
+	retval = local_password_change( name, 0, pass, err_str, sizeof(err_str),
+	                                 msg_str, sizeof(msg_str) );
+	if (!retval && *err_str)
+	{
+	    err_str[PSTRING_LEN-1] = '\0';
+	    make_remark( pamh, ctrl, PAM_ERROR_MSG, err_str );
+	}
+	else if (*msg_str)
+	{
+	    msg_str[PSTRING_LEN-1] = '\0';
+	    make_remark( pamh, ctrl, PAM_TEXT_INFO, msg_str );
+	}
+    }
+   }
+    
+    pass = NULL;
+
+    return PAM_IGNORE;
+}
+
+
+/* static module data */
+#ifdef PAM_STATIC
+struct pam_module _pam_smbpass_auth_modstruct = {
+     "pam_smbpass",
+     pam_sm_authenticate,
+     pam_sm_setcred,
+     NULL,
+     NULL,
+     NULL,
+     NULL
+};
+#endif
+