From 99cb69fca3d8374df3a85ec76180fc4e6acb15f8 Mon Sep 17 00:00:00 2001
From: =?utf8?q?G=C3=BCnther=20Deschner?= <gd@samba.org>
Date: Mon, 23 Aug 2010 16:02:23 +0200
Subject: [PATCH] s3-dcerpc: avoid talloc_move on schannel creds in
 cli_rpc_pipe_open_schannel_with_key().

Initially, the schannel creds were talloc memduped, then, during the netlogon
creds client merge (baf7274fed2f1ae7a9e3a57160bf5471566e636c) they were first
talloc_referenced and then later (53765c81f726a8c056cc4e57004592dd489975c9)
talloc_moved.

The issue with using talloc_move here is that users of that function in winbind
will only be able to have two schanneled connections, as the cached schannel
credentials pointer from the netlogon pipe will be set to NULL. Do a deep copy
of the struct instead.

Guenther
(cherry picked from commit 898c6123355a3a11ec17f0396c4cb3018c75c184)
(cherry picked from commit 68e83f9fedf0a0f0fa412d3ecec8ee853bf82bac)
---
 libcli/auth/credentials.c     | 46 ++++++++++++++++++++++++++++++++++++++++++-
 libcli/auth/proto.h           |  2 ++
 source3/rpc_client/cli_pipe.c | 10 +++++++---
 3 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/libcli/auth/credentials.c b/libcli/auth/credentials.c
index 87d1866ca49..504f5948294 100644
--- a/libcli/auth/credentials.c
+++ b/libcli/auth/credentials.c
@@ -24,6 +24,7 @@
 #include "system/time.h"
 #include "../lib/crypto/crypto.h"
 #include "libcli/auth/libcli_auth.h"
+#include "../libcli/security/dom_sid.h"
 
 static void netlogon_creds_step_crypt(struct netlogon_creds_CredentialState *creds,
 				      const struct netr_Credential *in,
@@ -202,7 +203,7 @@ struct netlogon_creds_CredentialState *netlogon_creds_client_init(TALLOC_CTX *me
 								  struct netr_Credential *initial_credential,
 								  uint32_t negotiate_flags)
 {
-	struct netlogon_creds_CredentialState *creds = talloc(mem_ctx, struct netlogon_creds_CredentialState);
+	struct netlogon_creds_CredentialState *creds = talloc_zero(mem_ctx, struct netlogon_creds_CredentialState);
 	
 	if (!creds) {
 		return NULL;
@@ -453,3 +454,46 @@ void netlogon_creds_decrypt_samlogon(struct netlogon_creds_CredentialState *cred
 	}
 }	
 
+/*
+  copy a netlogon_creds_CredentialState struct
+*/
+
+struct netlogon_creds_CredentialState *netlogon_creds_copy(TALLOC_CTX *mem_ctx,
+							   struct netlogon_creds_CredentialState *creds_in)
+{
+	struct netlogon_creds_CredentialState *creds = talloc_zero(mem_ctx, struct netlogon_creds_CredentialState);
+
+	if (!creds) {
+		return NULL;
+	}
+
+	creds->sequence			= creds_in->sequence;
+	creds->negotiate_flags		= creds_in->negotiate_flags;
+	creds->secure_channel_type	= creds_in->secure_channel_type;
+
+	creds->computer_name = talloc_strdup(creds, creds_in->computer_name);
+	if (!creds->computer_name) {
+		talloc_free(creds);
+		return NULL;
+	}
+	creds->account_name = talloc_strdup(creds, creds_in->account_name);
+	if (!creds->account_name) {
+		talloc_free(creds);
+		return NULL;
+	}
+
+	if (creds_in->sid) {
+		creds->sid = dom_sid_dup(creds, creds_in->sid);
+		if (!creds->sid) {
+			talloc_free(creds);
+			return NULL;
+		}
+	}
+
+	memcpy(creds->session_key, creds_in->session_key, sizeof(creds->session_key));
+	memcpy(creds->seed.data, creds_in->seed.data, sizeof(creds->seed.data));
+	memcpy(creds->client.data, creds_in->client.data, sizeof(creds->client.data));
+	memcpy(creds->server.data, creds_in->server.data, sizeof(creds->server.data));
+
+	return creds;
+}
diff --git a/libcli/auth/proto.h b/libcli/auth/proto.h
index e09cdee518c..c3878f5afac 100644
--- a/libcli/auth/proto.h
+++ b/libcli/auth/proto.h
@@ -35,6 +35,8 @@ void netlogon_creds_client_authenticator(struct netlogon_creds_CredentialState *
 				struct netr_Authenticator *next);
 bool netlogon_creds_client_check(struct netlogon_creds_CredentialState *creds,
 			const struct netr_Credential *received_credentials);
+struct netlogon_creds_CredentialState *netlogon_creds_copy(TALLOC_CTX *mem_ctx,
+							   struct netlogon_creds_CredentialState *creds_in);
 
 /*****************************************************************
 The above functions are common to the client and server interface
diff --git a/source3/rpc_client/cli_pipe.c b/source3/rpc_client/cli_pipe.c
index ee60c1db044..06b9c5dfcbc 100644
--- a/source3/rpc_client/cli_pipe.c
+++ b/source3/rpc_client/cli_pipe.c
@@ -3213,7 +3213,7 @@ NTSTATUS rpccli_schannel_bind_data(TALLOC_CTX *mem_ctx, const char *domain,
 	result->a_u.schannel_auth->state = SCHANNEL_STATE_START;
 	result->a_u.schannel_auth->seq_num = 0;
 	result->a_u.schannel_auth->initiator = true;
-	result->a_u.schannel_auth->creds = creds;
+	result->a_u.schannel_auth->creds = netlogon_creds_copy(result, creds);
 
 	*presult = result;
 	return NT_STATUS_OK;
@@ -4044,9 +4044,13 @@ NTSTATUS cli_rpc_pipe_open_schannel_with_key(struct cli_state *cli,
 
 	/*
 	 * The credentials on a new netlogon pipe are the ones we are passed
-	 * in - reference them in
+	 * in - copy them over
 	 */
-	result->dc = talloc_move(result, pdc);
+	result->dc = netlogon_creds_copy(result, *pdc);
+	if (result->dc == NULL) {
+		TALLOC_FREE(result);
+		return NT_STATUS_NO_MEMORY;
+	}
 
 	DEBUG(10,("cli_rpc_pipe_open_schannel_with_key: opened pipe %s to machine %s "
 		  "for domain %s and bound using schannel.\n",
-- 
2.11.4.GIT