--- /dev/null
+/*
+ Unix SMB/CIFS implementation.
+ Authenticate to a remote server
+ Copyright (C) Andrew Tridgell 1992-1998
+ Copyright (C) Andrew Bartlett 2001
+
+ 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"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_AUTH
+
+extern userdom_struct current_user_info;
+
+/****************************************************************************
+ Support for server level security.
+****************************************************************************/
+
+static struct cli_state *server_cryptkey(TALLOC_CTX *mem_ctx)
+{
+ struct cli_state *cli = NULL;
+ fstring desthost;
+ struct in_addr dest_ip;
+ const char *p;
+ char *pserver;
+ BOOL connected_ok = False;
+
+ if (!(cli = cli_initialise(cli)))
+ return NULL;
+
+ /* security = server just can't function with spnego */
+ cli->use_spnego = False;
+
+ pserver = talloc_strdup(mem_ctx, lp_passwordserver());
+ p = pserver;
+
+ while(next_token( &p, desthost, LIST_SEP, sizeof(desthost))) {
+ standard_sub_basic(current_user_info.smb_name, desthost, sizeof(desthost));
+ strupper_m(desthost);
+
+ if(!resolve_name( desthost, &dest_ip, 0x20)) {
+ DEBUG(1,("server_cryptkey: Can't resolve address for %s\n",desthost));
+ continue;
+ }
+
+ if (ismyip(dest_ip)) {
+ DEBUG(1,("Password server loop - disabling password server %s\n",desthost));
+ continue;
+ }
+
+ /* we use a mutex to prevent two connections at once - when a
+ Win2k PDC get two connections where one hasn't completed a
+ session setup yet it will send a TCP reset to the first
+ connection (tridge) */
+
+ if (!grab_server_mutex(desthost)) {
+ return NULL;
+ }
+
+ if (cli_connect(cli, desthost, &dest_ip)) {
+ DEBUG(3,("connected to password server %s\n",desthost));
+ connected_ok = True;
+ break;
+ }
+ }
+
+ if (!connected_ok) {
+ release_server_mutex();
+ DEBUG(0,("password server not available\n"));
+ cli_shutdown(cli);
+ return NULL;
+ }
+
+ if (!attempt_netbios_session_request(cli, global_myname(),
+ desthost, &dest_ip)) {
+ release_server_mutex();
+ DEBUG(1,("password server fails session request\n"));
+ cli_shutdown(cli);
+ return NULL;
+ }
+
+ if (strequal(desthost,myhostname())) {
+ exit_server("Password server loop!");
+ }
+
+ DEBUG(3,("got session\n"));
+
+ if (!cli_negprot(cli)) {
+ DEBUG(1,("%s rejected the negprot\n",desthost));
+ release_server_mutex();
+ cli_shutdown(cli);
+ return NULL;
+ }
+
+ if (cli->protocol < PROTOCOL_LANMAN2 ||
+ !(cli->sec_mode & NEGOTIATE_SECURITY_USER_LEVEL)) {
+ DEBUG(1,("%s isn't in user level security mode\n",desthost));
+ release_server_mutex();
+ cli_shutdown(cli);
+ return NULL;
+ }
+
+ /* Get the first session setup done quickly, to avoid silly
+ Win2k bugs. (The next connection to the server will kill
+ this one...
+ */
+
+ if (!cli_session_setup(cli, "", "", 0, "", 0,
+ "")) {
+ DEBUG(0,("%s rejected the initial session setup (%s)\n",
+ desthost, cli_errstr(cli)));
+ release_server_mutex();
+ cli_shutdown(cli);
+ return NULL;
+ }
+
+ release_server_mutex();
+
+ DEBUG(3,("password server OK\n"));
+
+ return cli;
+}
+
+/****************************************************************************
+ Clean up our allocated cli.
+****************************************************************************/
+
+static void free_server_private_data(void **private_data_pointer)
+{
+ struct cli_state **cli = (struct cli_state **)private_data_pointer;
+ if (*cli && (*cli)->initialised) {
+ DEBUG(10, ("Shutting down smbserver connection\n"));
+ cli_shutdown(*cli);
+ }
+ *private_data_pointer = NULL;
+}
+
+/****************************************************************************
+ Send a 'keepalive' packet down the cli pipe.
+****************************************************************************/
+
+static void send_server_keepalive(void **private_data_pointer)
+{
+ /* also send a keepalive to the password server if its still
+ connected */
+ if (private_data_pointer) {
+ struct cli_state *cli = (struct cli_state *)(*private_data_pointer);
+ if (cli && cli->initialised) {
+ if (!send_keepalive(cli->fd)) {
+ DEBUG( 2, ( "send_server_keepalive: password server keepalive failed.\n"));
+ cli_shutdown(cli);
+ *private_data_pointer = NULL;
+ }
+ }
+ }
+}
+
+/****************************************************************************
+ Get the challenge out of a password server.
+****************************************************************************/
+
+static DATA_BLOB auth_get_challenge_server(const struct auth_context *auth_context,
+ void **my_private_data,
+ TALLOC_CTX *mem_ctx)
+{
+ struct cli_state *cli = server_cryptkey(mem_ctx);
+
+ if (cli) {
+ DEBUG(3,("using password server validation\n"));
+
+ if ((cli->sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) == 0) {
+ /* We can't work with unencrypted password servers
+ unless 'encrypt passwords = no' */
+ DEBUG(5,("make_auth_info_server: Server is unencrypted, no challenge available..\n"));
+
+ /* However, it is still a perfectly fine connection
+ to pass that unencrypted password over */
+ *my_private_data = (void *)cli;
+ return data_blob(NULL, 0);
+
+ } else if (cli->secblob.length < 8) {
+ /* We can't do much if we don't get a full challenge */
+ DEBUG(2,("make_auth_info_server: Didn't receive a full challenge from server\n"));
+ cli_shutdown(cli);
+ return data_blob(NULL, 0);
+ }
+
+ *my_private_data = (void *)cli;
+
+ /* The return must be allocated on the caller's mem_ctx, as our own will be
+ destoyed just after the call. */
+ return data_blob_talloc(auth_context->mem_ctx, cli->secblob.data,8);
+ } else {
+ return data_blob(NULL, 0);
+ }
+}
+
+
+/****************************************************************************
+ Check for a valid username and password in security=server mode.
+ - Validate a password with the password server.
+****************************************************************************/
+
+static NTSTATUS check_smbserver_security(const struct auth_context *auth_context,
+ void *my_private_data,
+ TALLOC_CTX *mem_ctx,
+ const auth_usersupplied_info *user_info,
+ auth_serversupplied_info **server_info)
+{
+ struct cli_state *cli;
+ static unsigned char badpass[24];
+ static fstring baduser;
+ static BOOL tested_password_server = False;
+ static BOOL bad_password_server = False;
+ NTSTATUS nt_status = NT_STATUS_NOT_IMPLEMENTED;
+ BOOL locally_made_cli = False;
+
+ /*
+ * Check that the requested domain is not our own machine name.
+ * If it is, we should never check the PDC here, we use our own local
+ * password file.
+ */
+
+ if(is_myname(user_info->domain.str)) {
+ DEBUG(3,("check_smbserver_security: Requested domain was for this machine.\n"));
+ return nt_status;
+ }
+
+ cli = my_private_data;
+
+ if (cli) {
+ } else {
+ cli = server_cryptkey(mem_ctx);
+ locally_made_cli = True;
+ }
+
+ if (!cli || !cli->initialised) {
+ DEBUG(1,("password server is not connected (cli not initilised)\n"));
+ return NT_STATUS_LOGON_FAILURE;
+ }
+
+ if ((cli->sec_mode & NEGOTIATE_SECURITY_CHALLENGE_RESPONSE) == 0) {
+ if (user_info->encrypted) {
+ DEBUG(1,("password server %s is plaintext, but we are encrypted. This just can't work :-(\n", cli->desthost));
+ return NT_STATUS_LOGON_FAILURE;
+ }
+ } else {
+ if (memcmp(cli->secblob.data, auth_context->challenge.data, 8) != 0) {
+ DEBUG(1,("the challenge that the password server (%s) supplied us is not the one we gave our client. This just can't work :-(\n", cli->desthost));
+ return NT_STATUS_LOGON_FAILURE;
+ }
+ }
+
+ if(badpass[0] == 0)
+ memset(badpass, 0x1f, sizeof(badpass));
+
+ if((user_info->nt_resp.length == sizeof(badpass)) &&
+ !memcmp(badpass, user_info->nt_resp.data, sizeof(badpass))) {
+ /*
+ * Very unlikely, our random bad password is the same as the users
+ * password.
+ */
+ memset(badpass, badpass[0]+1, sizeof(badpass));
+ }
+
+ if(baduser[0] == 0) {
+ fstrcpy(baduser, INVALID_USER_PREFIX);
+ fstrcat(baduser, global_myname());
+ }
+
+ /*
+ * Attempt a session setup with a totally incorrect password.
+ * If this succeeds with the guest bit *NOT* set then the password
+ * server is broken and is not correctly setting the guest bit. We
+ * need to detect this as some versions of NT4.x are broken. JRA.
+ */
+
+ /* I sure as hell hope that there aren't servers out there that take
+ * NTLMv2 and have this bug, as we don't test for that...
+ * - abartlet@samba.org
+ */
+
+ if ((!tested_password_server) && (lp_paranoid_server_security())) {
+ if (cli_session_setup(cli, baduser, (char *)badpass, sizeof(badpass),
+ (char *)badpass, sizeof(badpass), user_info->domain.str)) {
+
+ /*
+ * We connected to the password server so we
+ * can say we've tested it.
+ */
+ tested_password_server = True;
+
+ if ((SVAL(cli->inbuf,smb_vwv2) & 1) == 0) {
+ DEBUG(0,("server_validate: password server %s allows users as non-guest \
+with a bad password.\n", cli->desthost));
+ DEBUG(0,("server_validate: This is broken (and insecure) behaviour. Please do not \
+use this machine as the password server.\n"));
+ cli_ulogoff(cli);
+
+ /*
+ * Password server has the bug.
+ */
+ bad_password_server = True;
+ return NT_STATUS_LOGON_FAILURE;
+ }
+ cli_ulogoff(cli);
+ }
+ } else {
+
+ /*
+ * We have already tested the password server.
+ * Fail immediately if it has the bug.
+ */
+
+ if(bad_password_server) {
+ DEBUG(0,("server_validate: [1] password server %s allows users as non-guest \
+with a bad password.\n", cli->desthost));
+ DEBUG(0,("server_validate: [1] This is broken (and insecure) behaviour. Please do not \
+use this machine as the password server.\n"));
+ return NT_STATUS_LOGON_FAILURE;
+ }
+ }
+
+ /*
+ * Now we know the password server will correctly set the guest bit, or is
+ * not guest enabled, we can try with the real password.
+ */
+
+ if (!user_info->encrypted) {
+ /* Plaintext available */
+ if (!cli_session_setup(cli, user_info->smb_name.str,
+ (char *)user_info->plaintext_password.data,
+ user_info->plaintext_password.length,
+ NULL, 0,
+ user_info->domain.str)) {
+ DEBUG(1,("password server %s rejected the password\n", cli->desthost));
+ /* Make this cli_nt_error() when the conversion is in */
+ nt_status = cli_nt_error(cli);
+ } else {
+ nt_status = NT_STATUS_OK;
+ }
+ } else {
+ if (!cli_session_setup(cli, user_info->smb_name.str,
+ (char *)user_info->lm_resp.data,
+ user_info->lm_resp.length,
+ (char *)user_info->nt_resp.data,
+ user_info->nt_resp.length,
+ user_info->domain.str)) {
+ DEBUG(1,("password server %s rejected the password\n", cli->desthost));
+ /* Make this cli_nt_error() when the conversion is in */
+ nt_status = cli_nt_error(cli);
+ } else {
+ nt_status = NT_STATUS_OK;
+ }
+ }
+
+ /* if logged in as guest then reject */
+ if ((SVAL(cli->inbuf,smb_vwv2) & 1) != 0) {
+ DEBUG(1,("password server %s gave us guest only\n", cli->desthost));
+ nt_status = NT_STATUS_LOGON_FAILURE;
+ }
+
+ cli_ulogoff(cli);
+
+ if (NT_STATUS_IS_OK(nt_status)) {
+ fstring real_username;
+ struct passwd *pass;
+
+ if ( (pass = smb_getpwnam( user_info->internal_username.str,
+ real_username, True )) != NULL )
+ {
+ nt_status = make_server_info_pw(server_info, pass->pw_name, pass);
+ passwd_free(&pass);
+ }
+ else
+ {
+ nt_status = NT_STATUS_NO_SUCH_USER;
+ }
+ }
+
+ if (locally_made_cli) {
+ cli_shutdown(cli);
+ }
+
+ return(nt_status);
+}
+
+static NTSTATUS auth_init_smbserver(struct auth_context *auth_context, const char* param, auth_methods **auth_method)
+{
+ if (!make_auth_methods(auth_context, auth_method)) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ (*auth_method)->name = "smbserver";
+ (*auth_method)->auth = check_smbserver_security;
+ (*auth_method)->get_chal = auth_get_challenge_server;
+ (*auth_method)->send_keepalive = send_server_keepalive;
+ (*auth_method)->free_private_data = free_server_private_data;
+ return NT_STATUS_OK;
+}
+
+NTSTATUS auth_server_init(void)
+{
+ return smb_register_auth(AUTH_INTERFACE_VERSION, "smbserver", auth_init_smbserver);
+}
projects / samba / blobdiff