Adding upstream version 2:4.17.12+dfsg.upstream/2%4.17.12+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 620 insertions, 0 deletions

diff --git a/source4/librpc/rpc/dcerpc_schannel.c b/source4/librpc/rpc/dcerpc_schannel.c
new file mode 100644
index 0000000..68bc3b3
--- /dev/null
+++ b/source4/librpc/rpc/dcerpc_schannel.c
@@ -0,0 +1,620 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   dcerpc schannel operations
+
+   Copyright (C) Andrew Tridgell 2004
+   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
+   Copyright (C) Rafal Szczesniak 2006
+
+   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 <tevent.h>
+#include "auth/auth.h"
+#include "libcli/composite/composite.h"
+#include "libcli/auth/libcli_auth.h"
+#include "librpc/gen_ndr/ndr_netlogon.h"
+#include "librpc/gen_ndr/ndr_netlogon_c.h"
+#include "auth/credentials/credentials.h"
+#include "librpc/rpc/dcerpc_proto.h"
+#include "param/param.h"
+#include "lib/param/loadparm.h"
+
+struct schannel_key_state {
+	struct dcerpc_pipe *pipe;
+	struct dcerpc_pipe *pipe2;
+	struct dcerpc_binding *binding;
+	bool dcerpc_schannel_auto;
+	struct cli_credentials *credentials;
+	struct netlogon_creds_CredentialState *creds;
+	uint32_t local_negotiate_flags;
+	uint32_t remote_negotiate_flags;
+	struct netr_Credential credentials1;
+	struct netr_Credential credentials2;
+	struct netr_Credential credentials3;
+	struct netr_ServerReqChallenge r;
+	struct netr_ServerAuthenticate2 a;
+	const struct samr_Password *mach_pwd;
+};
+
+
+static void continue_secondary_connection(struct composite_context *ctx);
+static void continue_bind_auth_none(struct composite_context *ctx);
+static void continue_srv_challenge(struct tevent_req *subreq);
+static void continue_srv_auth2(struct tevent_req *subreq);
+static void continue_get_capabilities(struct tevent_req *subreq);
+
+
+/*
+  Stage 2 of schannel_key: Receive endpoint mapping and request secondary
+  rpc connection
+*/
+static void continue_epm_map_binding(struct composite_context *ctx)
+{
+	struct composite_context *c;
+	struct schannel_key_state *s;
+	struct composite_context *sec_conn_req;
+
+	c = talloc_get_type(ctx->async.private_data, struct composite_context);
+	s = talloc_get_type(c->private_data, struct schannel_key_state);
+
+	/* receive endpoint mapping */
+	c->status = dcerpc_epm_map_binding_recv(ctx);
+	if (!NT_STATUS_IS_OK(c->status)) {
+		DEBUG(0,("Failed to map DCERPC/TCP NCACN_NP pipe for '%s' - %s\n",
+			 NDR_NETLOGON_UUID, nt_errstr(c->status)));
+		composite_error(c, c->status);
+		return;
+	}
+
+	/* send a request for secondary rpc connection */
+	sec_conn_req = dcerpc_secondary_connection_send(s->pipe,
+							s->binding);
+	if (composite_nomem(sec_conn_req, c)) return;
+
+	composite_continue(c, sec_conn_req, continue_secondary_connection, c);
+}
+
+
+/*
+  Stage 3 of schannel_key: Receive secondary rpc connection and perform
+  non-authenticated bind request
+*/
+static void continue_secondary_connection(struct composite_context *ctx)
+{
+	struct composite_context *c;
+	struct schannel_key_state *s;
+	struct composite_context *auth_none_req;
+
+	c = talloc_get_type(ctx->async.private_data, struct composite_context);
+	s = talloc_get_type(c->private_data, struct schannel_key_state);
+
+	/* receive secondary rpc connection */
+	c->status = dcerpc_secondary_connection_recv(ctx, &s->pipe2);
+	if (!composite_is_ok(c)) return;
+
+	talloc_steal(s, s->pipe2);
+
+	/* initiate a non-authenticated bind */
+	auth_none_req = dcerpc_bind_auth_none_send(c, s->pipe2, &ndr_table_netlogon);
+	if (composite_nomem(auth_none_req, c)) return;
+
+	composite_continue(c, auth_none_req, continue_bind_auth_none, c);
+}
+
+
+/*
+  Stage 4 of schannel_key: Receive non-authenticated bind and get
+  a netlogon challenge
+*/
+static void continue_bind_auth_none(struct composite_context *ctx)
+{
+	struct composite_context *c;
+	struct schannel_key_state *s;
+	struct tevent_req *subreq;
+
+	c = talloc_get_type(ctx->async.private_data, struct composite_context);
+	s = talloc_get_type(c->private_data, struct schannel_key_state);
+
+	/* receive result of non-authenticated bind request */
+	c->status = dcerpc_bind_auth_none_recv(ctx);
+	if (!composite_is_ok(c)) return;
+	
+	/* prepare a challenge request */
+	s->r.in.server_name   = talloc_asprintf(c, "\\\\%s", dcerpc_server_name(s->pipe));
+	if (composite_nomem(s->r.in.server_name, c)) return;
+	s->r.in.computer_name = cli_credentials_get_workstation(s->credentials);
+	s->r.in.credentials   = &s->credentials1;
+	s->r.out.return_credentials  = &s->credentials2;
+	
+	generate_random_buffer(s->credentials1.data, sizeof(s->credentials1.data));
+
+	/*
+	  request a netlogon challenge - a rpc request over opened secondary pipe
+	*/
+	subreq = dcerpc_netr_ServerReqChallenge_r_send(s, c->event_ctx,
+						       s->pipe2->binding_handle,
+						       &s->r);
+	if (composite_nomem(subreq, c)) return;
+
+	tevent_req_set_callback(subreq, continue_srv_challenge, c);
+}
+
+
+/*
+  Stage 5 of schannel_key: Receive a challenge and perform authentication
+  on the netlogon pipe
+*/
+static void continue_srv_challenge(struct tevent_req *subreq)
+{
+	struct composite_context *c;
+	struct schannel_key_state *s;
+
+	c = tevent_req_callback_data(subreq, struct composite_context);
+	s = talloc_get_type(c->private_data, struct schannel_key_state);
+
+	/* receive rpc request result - netlogon challenge */
+	c->status = dcerpc_netr_ServerReqChallenge_r_recv(subreq, s);
+	TALLOC_FREE(subreq);
+	if (!composite_is_ok(c)) return;
+
+	/* prepare credentials for auth2 request */
+	s->mach_pwd = cli_credentials_get_nt_hash(s->credentials, c);
+
+	/* auth2 request arguments */
+	s->a.in.server_name      = s->r.in.server_name;
+	s->a.in.account_name     = cli_credentials_get_username(s->credentials);
+	s->a.in.secure_channel_type =
+		cli_credentials_get_secure_channel_type(s->credentials);
+	s->a.in.computer_name    = cli_credentials_get_workstation(s->credentials);
+	s->a.in.negotiate_flags  = &s->local_negotiate_flags;
+	s->a.in.credentials      = &s->credentials3;
+	s->a.out.negotiate_flags = &s->remote_negotiate_flags;
+	s->a.out.return_credentials     = &s->credentials3;
+
+	s->creds = netlogon_creds_client_init(s, 
+					      s->a.in.account_name, 
+					      s->a.in.computer_name,
+					      s->a.in.secure_channel_type,
+					      &s->credentials1, &s->credentials2,
+					      s->mach_pwd, &s->credentials3,
+					      s->local_negotiate_flags);
+	if (composite_nomem(s->creds, c)) {
+		return;
+	}
+	/*
+	  authenticate on the netlogon pipe - a rpc request over secondary pipe
+	*/
+	subreq = dcerpc_netr_ServerAuthenticate2_r_send(s, c->event_ctx,
+							s->pipe2->binding_handle,
+							&s->a);
+	if (composite_nomem(subreq, c)) return;
+
+	tevent_req_set_callback(subreq, continue_srv_auth2, c);
+}
+
+
+/*
+  Stage 6 of schannel_key: Receive authentication request result and verify
+  received credentials
+*/
+static void continue_srv_auth2(struct tevent_req *subreq)
+{
+	struct composite_context *c;
+	struct schannel_key_state *s;
+
+	c = tevent_req_callback_data(subreq, struct composite_context);
+	s = talloc_get_type(c->private_data, struct schannel_key_state);
+
+	/* receive rpc request result - auth2 credentials */ 
+	c->status = dcerpc_netr_ServerAuthenticate2_r_recv(subreq, s);
+	TALLOC_FREE(subreq);
+	if (!composite_is_ok(c)) return;
+
+	if (!NT_STATUS_EQUAL(s->a.out.result, NT_STATUS_ACCESS_DENIED) &&
+	    !NT_STATUS_IS_OK(s->a.out.result)) {
+		composite_error(c, s->a.out.result);
+		return;
+	}
+
+	/*
+	 * Strong keys could be unsupported (NT4) or disables. So retry with the
+	 * flags returned by the server. - asn
+	 */
+	if (NT_STATUS_EQUAL(s->a.out.result, NT_STATUS_ACCESS_DENIED)) {
+		uint32_t lf = s->local_negotiate_flags;
+		const char *ln = NULL;
+		uint32_t rf = s->remote_negotiate_flags;
+		const char *rn = NULL;
+
+		if (!s->dcerpc_schannel_auto) {
+			composite_error(c, s->a.out.result);
+			return;
+		}
+		s->dcerpc_schannel_auto = false;
+
+		if (lf & NETLOGON_NEG_SUPPORTS_AES)  {
+			ln = "aes";
+			if (rf & NETLOGON_NEG_SUPPORTS_AES) {
+				composite_error(c, s->a.out.result);
+				return;
+			}
+		} else if (lf & NETLOGON_NEG_STRONG_KEYS) {
+			ln = "strong";
+			if (rf & NETLOGON_NEG_STRONG_KEYS) {
+				composite_error(c, s->a.out.result);
+				return;
+			}
+		} else {
+			ln = "des";
+		}
+
+		if (rf & NETLOGON_NEG_SUPPORTS_AES)  {
+			rn = "aes";
+		} else if (rf & NETLOGON_NEG_STRONG_KEYS) {
+			rn = "strong";
+		} else {
+			rn = "des";
+		}
+
+		DEBUG(3, ("Server doesn't support %s keys, downgrade to %s"
+			  "and retry! local[0x%08X] remote[0x%08X]\n",
+			  ln, rn, lf, rf));
+
+		s->local_negotiate_flags = s->remote_negotiate_flags;
+
+		generate_random_buffer(s->credentials1.data,
+				       sizeof(s->credentials1.data));
+
+		subreq = dcerpc_netr_ServerReqChallenge_r_send(s,
+							       c->event_ctx,
+							       s->pipe2->binding_handle,
+							       &s->r);
+		if (composite_nomem(subreq, c)) return;
+
+		tevent_req_set_callback(subreq, continue_srv_challenge, c);
+		return;
+	}
+
+	s->creds->negotiate_flags = s->remote_negotiate_flags;
+
+	/* verify credentials */
+	if (!netlogon_creds_client_check(s->creds, s->a.out.return_credentials)) {
+		composite_error(c, NT_STATUS_UNSUCCESSFUL);
+		return;
+	}
+
+	composite_done(c);
+}
+
+/*
+  Initiate establishing a schannel key using netlogon challenge
+  on a secondary pipe
+*/
+static struct composite_context *dcerpc_schannel_key_send(TALLOC_CTX *mem_ctx,
+						   struct dcerpc_pipe *p,
+						   struct cli_credentials *credentials,
+						   struct loadparm_context *lp_ctx)
+{
+	struct composite_context *c;
+	struct schannel_key_state *s;
+	struct composite_context *epm_map_req;
+	enum netr_SchannelType schannel_type = cli_credentials_get_secure_channel_type(credentials);
+	struct cli_credentials *epm_creds = NULL;
+
+	/* composite context allocation and setup */
+	c = composite_create(mem_ctx, p->conn->event_ctx);
+	if (c == NULL) return NULL;
+
+	s = talloc_zero(c, struct schannel_key_state);
+	if (composite_nomem(s, c)) return c;
+	c->private_data = s;
+
+	/* store parameters in the state structure */
+	s->pipe        = p;
+	s->credentials = credentials;
+	s->local_negotiate_flags = NETLOGON_NEG_AUTH2_FLAGS;
+
+	/* allocate credentials */
+	if (s->pipe->conn->flags & DCERPC_SCHANNEL_128) {
+		s->local_negotiate_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
+	}
+	if (s->pipe->conn->flags & DCERPC_SCHANNEL_AES) {
+		s->local_negotiate_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
+		s->local_negotiate_flags |= NETLOGON_NEG_SUPPORTS_AES;
+	}
+	if (s->pipe->conn->flags & DCERPC_SCHANNEL_AUTO) {
+		s->local_negotiate_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
+		s->local_negotiate_flags |= NETLOGON_NEG_SUPPORTS_AES;
+		s->dcerpc_schannel_auto = true;
+	}
+
+	/* type of authentication depends on schannel type */
+	if (schannel_type == SEC_CHAN_RODC) {
+		s->local_negotiate_flags |= NETLOGON_NEG_RODC_PASSTHROUGH;
+	}
+
+	if (lpcfg_weak_crypto(lp_ctx) == SAMBA_WEAK_CRYPTO_DISALLOWED) {
+		s->local_negotiate_flags &= ~NETLOGON_NEG_ARCFOUR;
+	}
+
+	epm_creds = cli_credentials_init_anon(s);
+	if (composite_nomem(epm_creds, c)) return c;
+
+	/* allocate binding structure */
+	s->binding = dcerpc_binding_dup(s, s->pipe->binding);
+	if (composite_nomem(s->binding, c)) return c;
+
+	/* request the netlogon endpoint mapping */
+	epm_map_req = dcerpc_epm_map_binding_send(c, s->binding,
+						  &ndr_table_netlogon,
+						  epm_creds,
+						  s->pipe->conn->event_ctx,
+						  lp_ctx);
+	if (composite_nomem(epm_map_req, c)) return c;
+
+	composite_continue(c, epm_map_req, continue_epm_map_binding, c);
+	return c;
+}
+
+
+/*
+  Receive result of schannel key request
+ */
+static NTSTATUS dcerpc_schannel_key_recv(struct composite_context *c,
+				TALLOC_CTX *mem_ctx,
+				struct netlogon_creds_CredentialState **creds)
+{
+	NTSTATUS status = composite_wait(c);
+
+	if (NT_STATUS_IS_OK(status)) {
+		struct schannel_key_state *s =
+			talloc_get_type_abort(c->private_data,
+			struct schannel_key_state);
+		*creds = talloc_move(mem_ctx, &s->creds);
+	}
+
+	talloc_free(c);
+	return status;
+}
+
+
+struct auth_schannel_state {
+	struct dcerpc_pipe *pipe;
+	struct cli_credentials *credentials;
+	const struct ndr_interface_table *table;
+	struct loadparm_context *lp_ctx;
+	uint8_t auth_level;
+	struct netlogon_creds_CredentialState *creds_state;
+	struct netlogon_creds_CredentialState save_creds_state;
+	struct netr_Authenticator auth;
+	struct netr_Authenticator return_auth;
+	union netr_Capabilities capabilities;
+	struct netr_LogonGetCapabilities c;
+};
+
+
+static void continue_bind_auth(struct composite_context *ctx);
+
+
+/*
+  Stage 2 of auth_schannel: Receive schannel key and intitiate an
+  authenticated bind using received credentials
+ */
+static void continue_schannel_key(struct composite_context *ctx)
+{
+	struct composite_context *auth_req;
+	struct composite_context *c = talloc_get_type(ctx->async.private_data,
+						      struct composite_context);
+	struct auth_schannel_state *s = talloc_get_type(c->private_data,
+							struct auth_schannel_state);
+	NTSTATUS status;
+
+	/* receive schannel key */
+	status = c->status = dcerpc_schannel_key_recv(ctx, s, &s->creds_state);
+	if (!composite_is_ok(c)) {
+		DEBUG(1, ("Failed to setup credentials: %s\n", nt_errstr(status)));
+		return;
+	}
+
+	/* send bind auth request with received creds */
+	cli_credentials_set_netlogon_creds(s->credentials, s->creds_state);
+
+	auth_req = dcerpc_bind_auth_send(c, s->pipe, s->table, s->credentials, 
+					 lpcfg_gensec_settings(c, s->lp_ctx),
+					 DCERPC_AUTH_TYPE_SCHANNEL, s->auth_level,
+					 NULL);
+	if (composite_nomem(auth_req, c)) return;
+	
+	composite_continue(c, auth_req, continue_bind_auth, c);
+}
+
+
+/*
+  Stage 3 of auth_schannel: Receivce result of authenticated bind
+  and say if we're done ok.
+*/
+static void continue_bind_auth(struct composite_context *ctx)
+{
+	struct composite_context *c = talloc_get_type(ctx->async.private_data,
+						      struct composite_context);
+	struct auth_schannel_state *s = talloc_get_type(c->private_data,
+							struct auth_schannel_state);
+	struct tevent_req *subreq;
+
+	c->status = dcerpc_bind_auth_recv(ctx);
+	if (!composite_is_ok(c)) return;
+
+	/* if we have a AES encrypted connection, verify the capabilities */
+	if (ndr_syntax_id_equal(&s->table->syntax_id,
+				&ndr_table_netlogon.syntax_id)) {
+		NTSTATUS status;
+		ZERO_STRUCT(s->return_auth);
+
+		s->save_creds_state = *s->creds_state;
+		status = netlogon_creds_client_authenticator(&s->save_creds_state,
+							     &s->auth);
+		if (!NT_STATUS_IS_OK(status)) {
+			composite_error(c, status);
+			return;
+		}
+
+		s->c.in.server_name = talloc_asprintf(c,
+						      "\\\\%s",
+						      dcerpc_server_name(s->pipe));
+		if (composite_nomem(s->c.in.server_name, c)) return;
+		s->c.in.computer_name         = cli_credentials_get_workstation(s->credentials);
+		s->c.in.credential            = &s->auth;
+		s->c.in.return_authenticator  = &s->return_auth;
+		s->c.in.query_level           = 1;
+
+		s->c.out.capabilities         = &s->capabilities;
+		s->c.out.return_authenticator = &s->return_auth;
+
+		DEBUG(5, ("We established a AES connection, verifying logon "
+			  "capabilities\n"));
+
+		subreq = dcerpc_netr_LogonGetCapabilities_r_send(s,
+								 c->event_ctx,
+								 s->pipe->binding_handle,
+								 &s->c);
+		if (composite_nomem(subreq, c)) return;
+
+		tevent_req_set_callback(subreq, continue_get_capabilities, c);
+		return;
+	}
+
+	composite_done(c);
+}
+
+/*
+  Stage 4 of auth_schannel: Get the Logon Capablities and verify them.
+*/
+static void continue_get_capabilities(struct tevent_req *subreq)
+{
+	struct composite_context *c;
+	struct auth_schannel_state *s;
+
+	c = tevent_req_callback_data(subreq, struct composite_context);
+	s = talloc_get_type(c->private_data, struct auth_schannel_state);
+
+	/* receive rpc request result */
+	c->status = dcerpc_netr_LogonGetCapabilities_r_recv(subreq, s);
+	TALLOC_FREE(subreq);
+	if (NT_STATUS_EQUAL(c->status, NT_STATUS_RPC_PROCNUM_OUT_OF_RANGE)) {
+		if (s->creds_state->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
+			composite_error(c, NT_STATUS_INVALID_NETWORK_RESPONSE);
+			return;
+		} else {
+			/* This is probably NT */
+			composite_done(c);
+			return;
+		}
+	} else if (!composite_is_ok(c)) {
+		return;
+	}
+
+	if (NT_STATUS_EQUAL(s->c.out.result, NT_STATUS_NOT_IMPLEMENTED)) {
+		if (s->creds_state->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) {
+			/* This means AES isn't supported. */
+			composite_error(c, NT_STATUS_INVALID_NETWORK_RESPONSE);
+			return;
+		}
+
+		/* This is probably an old Samba version */
+		composite_done(c);
+		return;
+	}
+
+	/* verify credentials */
+	if (!netlogon_creds_client_check(&s->save_creds_state,
+					 &s->c.out.return_authenticator->cred)) {
+		composite_error(c, NT_STATUS_UNSUCCESSFUL);
+		return;
+	}
+
+	*s->creds_state = s->save_creds_state;
+	cli_credentials_set_netlogon_creds(s->credentials, s->creds_state);
+
+	if (!NT_STATUS_IS_OK(s->c.out.result)) {
+		composite_error(c, s->c.out.result);
+		return;
+	}
+
+	/* compare capabilities */
+	if (s->creds_state->negotiate_flags != s->capabilities.server_capabilities) {
+		DEBUG(2, ("The client capabilities don't match the server "
+			  "capabilities: local[0x%08X] remote[0x%08X]\n",
+			  s->creds_state->negotiate_flags,
+			  s->capabilities.server_capabilities));
+		composite_error(c, NT_STATUS_INVALID_NETWORK_RESPONSE);
+		return;
+	}
+
+	/* TODO: Add downgrade dectection. */
+
+	composite_done(c);
+}
+
+
+/*
+  Initiate schannel authentication request
+*/
+struct composite_context *dcerpc_bind_auth_schannel_send(TALLOC_CTX *tmp_ctx, 
+							 struct dcerpc_pipe *p,
+							 const struct ndr_interface_table *table,
+							 struct cli_credentials *credentials,
+							 struct loadparm_context *lp_ctx,
+							 uint8_t auth_level)
+{
+	struct composite_context *c;
+	struct auth_schannel_state *s;
+	struct composite_context *schan_key_req;
+
+	/* composite context allocation and setup */
+	c = composite_create(tmp_ctx, p->conn->event_ctx);
+	if (c == NULL) return NULL;
+	
+	s = talloc_zero(c, struct auth_schannel_state);
+	if (composite_nomem(s, c)) return c;
+	c->private_data = s;
+
+	/* store parameters in the state structure */
+	s->pipe        = p;
+	s->credentials = credentials;
+	s->table       = table;
+	s->auth_level  = auth_level;
+	s->lp_ctx      = lp_ctx;
+
+	/* start getting schannel key first */
+	schan_key_req = dcerpc_schannel_key_send(c, p, credentials, lp_ctx);
+	if (composite_nomem(schan_key_req, c)) return c;
+
+	composite_continue(c, schan_key_req, continue_schannel_key, c);
+	return c;
+}
+
+
+/*
+  Receive result of schannel authentication request
+*/
+NTSTATUS dcerpc_bind_auth_schannel_recv(struct composite_context *c)
+{
+	NTSTATUS status = composite_wait(c);
+	
+	talloc_free(c);
+	return status;
+}