s3-auth Add auth_samba4 module

This module makes a direct call into the Samba4 auth stack to
authenticate Samba4 uses in a Samba3 file server.  The direct call
avoids the need to obtain schannel credentials.

Andrew Bartlett

Pair-Programmed-With: Andrew Tridgell <tridge@samba.org>

2 files changed, 141 insertions, 0 deletions

diff --git a/source3/auth/auth_samba4.c b/source3/auth/auth_samba4.c
new file mode 100644
index 0000000000..57c07dd716
--- /dev/null
+++ b/source3/auth/auth_samba4.c
@@ -0,0 +1,132 @@
+/*
+   Unix SMB/CIFS implementation.
+   Authenticate against Samba4's auth subsystem
+   Copyright (C) Volker Lendecke 2008
+   Copyright (C) Andrew Bartlett 2010
+
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "source3/include/auth.h"
+#include "source4/auth/auth.h"
+#include "auth/auth_sam_reply.h"
+#include "param/param.h"
+#include "source4/lib/events/events.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_AUTH
+
+static NTSTATUS check_samba4_security(const struct auth_context *auth_context,
+				      void *my_private_data,
+				      TALLOC_CTX *mem_ctx,
+				      const struct auth_usersupplied_info *user_info,
+				      struct auth_serversupplied_info **server_info)
+{
+	TALLOC_CTX *frame = talloc_stackframe();
+	struct netr_SamInfo3 *info3 = NULL;
+	NTSTATUS nt_status;
+	struct auth_user_info_dc *user_info_dc;
+	struct auth4_context *auth4_context;
+	struct loadparm_context *lp_ctx;
+	const char *config_file;
+
+	lp_ctx = loadparm_init(frame);
+	if (lp_ctx == NULL) {
+		DEBUG(10, ("loadparm_init failed\n"));
+		talloc_free(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	if (lp_loaded()) {
+		config_file = lp_configfile();
+	}
+	if (!config_file || !config_file[0]) {
+		config_file = get_dyn_CONFIGFILE();
+	}
+
+	if (!lpcfg_load(lp_ctx, config_file)) {
+		DEBUG(1, ("s4 lpcfg_load() of s3 config file %s failed", config_file));
+		talloc_free(frame);
+		return NT_STATUS_INVALID_SERVER_STATE;
+	}
+
+	/* We create a private tevent context here to avoid nested loops in
+	 * the s3 one, as that may not be expected */
+	nt_status = auth_context_create(mem_ctx,
+					s4_event_context_init(frame), NULL, 
+					lp_ctx,
+					&auth4_context);
+	NT_STATUS_NOT_OK_RETURN(nt_status);
+		
+	nt_status = auth_context_set_challenge(auth4_context, auth_context->challenge.data, "auth_samba4");
+	NT_STATUS_NOT_OK_RETURN_AND_FREE(nt_status, auth4_context);
+
+	nt_status = auth_check_password(auth4_context, auth4_context, user_info, &user_info_dc);
+	NT_STATUS_NOT_OK_RETURN_AND_FREE(nt_status, auth4_context);
+	
+	nt_status = auth_convert_user_info_dc_saminfo3(mem_ctx,
+						       user_info_dc,
+						       &info3);
+	if (NT_STATUS_IS_OK(nt_status)) {
+		/* We need the strings from the server_info to be valid as long as the info3 is around */
+		talloc_steal(info3, user_info_dc);
+	}
+	talloc_free(auth4_context);
+
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		goto done;
+	}
+
+	nt_status = make_server_info_info3(mem_ctx, user_info->client.account_name,
+					   user_info->mapped.domain_name, server_info,
+					info3);
+	if (!NT_STATUS_IS_OK(nt_status)) {
+		DEBUG(10, ("make_server_info_info3 failed: %s\n",
+			   nt_errstr(nt_status)));
+		TALLOC_FREE(frame);
+		return nt_status;
+	}
+
+	nt_status = NT_STATUS_OK;
+
+ done:
+	TALLOC_FREE(frame);
+	return nt_status;
+}
+
+/* module initialisation */
+static NTSTATUS auth_init_samba4(struct auth_context *auth_context,
+				    const char *param,
+				    auth_methods **auth_method)
+{
+	struct auth_methods *result;
+
+	result = TALLOC_ZERO_P(auth_context, struct auth_methods);
+	if (result == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	result->name = "samba4";
+	result->auth = check_samba4_security;
+
+        *auth_method = result;
+	return NT_STATUS_OK;
+}
+
+NTSTATUS auth_samba4_init(void)
+{
+	smb_register_auth(AUTH_INTERFACE_VERSION, "samba4",
+			  auth_init_samba4);
+	return NT_STATUS_OK;
+}
diff --git a/source3/auth/wscript_build b/source3/auth/wscript_build
index 8bf2051526..dc59c87c60 100644
--- a/source3/auth/wscript_build
+++ b/source3/auth/wscript_build
@@ -96,3 +96,12 @@ bld.SAMBA3_MODULE('auth_script',
                  init_function='',
                  internal_module=bld.SAMBA3_IS_STATIC_MODULE('auth_script'),
                  enabled=bld.SAMBA3_IS_ENABLED_MODULE('auth_script'))
+
+bld.SAMBA3_MODULE('auth_samba4',
+                  subsystem='auth',
+                  source='auth_samba4.c',
+                  init_function='',
+                  deps='auth4',
+                  allow_undefined_symbols=False,
+                  internal_module=bld.SAMBA3_IS_STATIC_MODULE('auth_samba4'),
+                  enabled=bld.SAMBA3_IS_ENABLED_MODULE('auth_samba4'))