Add SMB encryption. Still fixing client decrypt but

negotiation works.
Jeremy.
(This used to be commit d78045601af787731f0737b8627450018902b104)

1 files changed, 703 insertions, 0 deletions

diff --git a/source3/smbd/seal.c b/source3/smbd/seal.c
new file mode 100644
index 0000000000..14a427bb9c
--- /dev/null
+++ b/source3/smbd/seal.c
@@ -0,0 +1,703 @@
+/* 
+   Unix SMB/CIFS implementation.
+   SMB Transport encryption (sealing) code - server code.
+   Copyright (C) Jeremy Allison 2007.
+   
+   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"
+
+/******************************************************************************
+ Server side encryption.
+******************************************************************************/
+
+/******************************************************************************
+ Global server state.
+******************************************************************************/
+
+struct smb_srv_trans_enc_ctx {
+	struct smb_trans_enc_state *es;
+	AUTH_NTLMSSP_STATE *auth_ntlmssp_state; /* Must be kept in sync with pointer in ec->ntlmssp_state. */
+};
+
+static struct smb_srv_trans_enc_ctx *partial_srv_trans_enc_ctx;
+static struct smb_srv_trans_enc_ctx *srv_trans_enc_ctx;
+
+/******************************************************************************
+ Is server encryption on ?
+******************************************************************************/
+
+bool srv_encryption_on(void)
+{
+	if (srv_trans_enc_ctx) {
+		return common_encryption_on(srv_trans_enc_ctx->es);
+	}
+	return false;
+}
+
+/******************************************************************************
+ Create an auth_ntlmssp_state and ensure pointer copy is correct.
+******************************************************************************/
+
+static NTSTATUS make_auth_ntlmssp(struct smb_srv_trans_enc_ctx *ec)
+{
+	NTSTATUS status = auth_ntlmssp_start(&ec->auth_ntlmssp_state);
+	if (!NT_STATUS_IS_OK(status)) {
+		return nt_status_squash(status);
+	}
+
+	/*
+	 * We must remember to update the pointer copy for the common
+	 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
+	 */
+	ec->es->s.ntlmssp_state = ec->auth_ntlmssp_state->ntlmssp_state;
+	return status;
+}
+
+/******************************************************************************
+ Destroy an auth_ntlmssp_state and ensure pointer copy is correct.
+******************************************************************************/
+
+static void destroy_auth_ntlmssp(struct smb_srv_trans_enc_ctx *ec)
+{
+	/*
+	 * We must remember to update the pointer copy for the common
+	 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
+	 */
+
+	if (ec->auth_ntlmssp_state) {
+		auth_ntlmssp_end(&ec->auth_ntlmssp_state);
+		/* The auth_ntlmssp_end killed this already. */
+		ec->es->s.ntlmssp_state = NULL;
+	}
+}
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+
+/******************************************************************************
+ Import a name.
+******************************************************************************/
+
+static NTSTATUS get_srv_gss_creds(const char *service,
+				const char *name,
+				gss_cred_usage_t cred_type,
+				gss_cred_id_t *p_srv_cred)
+{
+	OM_uint32 ret;
+	OM_uint32 min;
+	gss_name_t srv_name;
+	gss_buffer_desc input_name;
+	char *host_princ_s = NULL;
+	NTSTATUS status = NT_STATUS_OK;
+
+	gss_OID_desc nt_hostbased_service =
+	{10, CONST_DISCARD(char *,"\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x04")};
+
+	asprintf(&host_princ_s, "%s@%s", service, name);
+	if (host_princ_s == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	input_name.value = host_princ_s;
+	input_name.length = strlen(host_princ_s) + 1;
+
+	ret = gss_import_name(&min,
+				&input_name,
+				&nt_hostbased_service,
+				&srv_name);
+
+	DEBUG(10,("get_srv_gss_creds: imported name %s\n",
+		host_princ_s ));
+
+	if (ret != GSS_S_COMPLETE) {
+		SAFE_FREE(host_princ_s);
+		return map_nt_error_from_gss(ret, min);
+	}
+
+	/*
+	 * We're accessing the krb5.keytab file here.
+ 	 * ensure we have permissions to do so.
+ 	 */
+	become_root();
+
+	ret = gss_acquire_cred(&min,
+				srv_name,
+				GSS_C_INDEFINITE,
+				GSS_C_NULL_OID_SET,
+				cred_type,
+				p_srv_cred,
+				NULL,
+				NULL);
+	unbecome_root();
+
+	if (ret != GSS_S_COMPLETE) {
+		ADS_STATUS adss = ADS_ERROR_GSS(ret, min);
+		DEBUG(10,("get_srv_gss_creds: gss_acquire_cred failed with %s\n",
+			ads_errstr(adss)));
+		status = map_nt_error_from_gss(ret, min);
+	}
+
+	SAFE_FREE(host_princ_s);
+	gss_release_name(&min, &srv_name);
+	return status;
+}
+
+/******************************************************************************
+ Create a gss state.
+ Try and get the cifs/server@realm principal first, then fall back to
+ host/server@realm.
+******************************************************************************/
+
+static NTSTATUS make_auth_gss(struct smb_srv_trans_enc_ctx *ec)
+{
+	NTSTATUS status;
+	gss_cred_id_t srv_cred;
+	fstring fqdn;
+
+	name_to_fqdn(fqdn, global_myname());
+	strlower_m(fqdn);
+
+	status = get_srv_gss_creds("cifs", fqdn, GSS_C_ACCEPT, &srv_cred);
+	if (!NT_STATUS_IS_OK(status)) {
+		status = get_srv_gss_creds("host", fqdn, GSS_C_ACCEPT, &srv_cred);
+		if (!NT_STATUS_IS_OK(status)) {
+			return nt_status_squash(status);
+		}
+	}
+
+	ec->es->s.gss_state = SMB_MALLOC_P(struct smb_tran_enc_state_gss);
+	if (!ec->es->s.gss_state) {
+		OM_uint32 min;
+		gss_release_cred(&min, &srv_cred);
+		return NT_STATUS_NO_MEMORY;
+	}
+	ZERO_STRUCTP(ec->es->s.gss_state);
+	ec->es->s.gss_state->creds = srv_cred;
+
+	/* No context yet. */
+	ec->es->s.gss_state->gss_ctx = GSS_C_NO_CONTEXT;
+
+	return NT_STATUS_OK;
+}
+#endif
+
+/******************************************************************************
+ Shutdown a server encryption context.
+******************************************************************************/
+
+static void srv_free_encryption_context(struct smb_srv_trans_enc_ctx **pp_ec)
+{
+	struct smb_srv_trans_enc_ctx *ec = *pp_ec;
+
+	if (!ec) {
+		return;
+	}
+
+	if (ec->es) {
+		switch (ec->es->smb_enc_type) {
+			case SMB_TRANS_ENC_NTLM:
+				destroy_auth_ntlmssp(ec);
+				break;
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+			case SMB_TRANS_ENC_GSS:
+				break;
+#endif
+		}
+		common_free_encryption_state(&ec->es);
+	}
+
+	SAFE_FREE(ec);
+	*pp_ec = NULL;
+}
+
+/******************************************************************************
+ Create a server encryption context.
+******************************************************************************/
+
+static NTSTATUS make_srv_encryption_context(enum smb_trans_enc_type smb_enc_type, struct smb_srv_trans_enc_ctx **pp_ec)
+{
+	struct smb_srv_trans_enc_ctx *ec;
+
+	*pp_ec = NULL;
+
+	ec = SMB_MALLOC_P(struct smb_srv_trans_enc_ctx);
+	if (!ec) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	ZERO_STRUCTP(partial_srv_trans_enc_ctx);
+	ec->es = SMB_MALLOC_P(struct smb_trans_enc_state);
+	if (!ec->es) {
+		SAFE_FREE(ec);
+		return NT_STATUS_NO_MEMORY;
+	}
+	ZERO_STRUCTP(ec->es);
+	ec->es->smb_enc_type = smb_enc_type;
+	switch (smb_enc_type) {
+		case SMB_TRANS_ENC_NTLM:
+			{
+				NTSTATUS status = make_auth_ntlmssp(ec);
+				if (!NT_STATUS_IS_OK(status)) {
+					srv_free_encryption_context(&ec);
+					return status;
+				}
+			}
+			break;
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+		case SMB_TRANS_ENC_GSS:
+			/* Acquire our credentials by calling gss_acquire_cred here. */
+			{
+				NTSTATUS status = make_auth_gss(ec);
+				if (!NT_STATUS_IS_OK(status)) {
+					srv_free_encryption_context(&ec);
+					return status;
+				}
+			}
+			break;
+#endif
+		default:
+			srv_free_encryption_context(&ec);
+			return NT_STATUS_INVALID_PARAMETER;
+	}
+	*pp_ec = ec;
+	return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Free an encryption-allocated buffer.
+******************************************************************************/
+
+void srv_free_enc_buffer(char *buf)
+{
+	/* We know this is an smb buffer, and we
+	 * didn't malloc, only copy, for a keepalive,
+	 * so ignore session keepalives. */
+
+	if(CVAL(buf,0) == SMBkeepalive) {
+		return;
+	}
+
+	if (srv_trans_enc_ctx) {
+		common_free_enc_buffer(srv_trans_enc_ctx->es, buf);
+	}
+}
+
+/******************************************************************************
+ Decrypt an incoming buffer.
+******************************************************************************/
+
+NTSTATUS srv_decrypt_buffer(char *buf)
+{
+	/* Ignore session keepalives. */
+	if(CVAL(buf,0) == SMBkeepalive) {
+		return NT_STATUS_OK;
+	}
+
+	if (srv_trans_enc_ctx) {
+		return common_decrypt_buffer(srv_trans_enc_ctx->es, buf);
+	}
+
+	return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
+******************************************************************************/
+
+NTSTATUS srv_encrypt_buffer(char *buf, char **buf_out)
+{
+	*buf_out = buf;
+
+	/* Ignore session keepalives. */
+	if(CVAL(buf,0) == SMBkeepalive) {
+		return NT_STATUS_OK;
+	}
+
+	if (srv_trans_enc_ctx) {
+		return common_encrypt_buffer(srv_trans_enc_ctx->es, buf, buf_out);
+	}
+	/* Not encrypting. */
+	return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Do the gss encryption negotiation. Parameters are in/out.
+ Until success we do everything on the partial enc ctx.
+******************************************************************************/
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+static NTSTATUS srv_enc_spnego_gss_negotiate(unsigned char **ppdata, size_t *p_data_size, DATA_BLOB secblob)
+{
+	OM_uint32 ret;
+	OM_uint32 min;
+	OM_uint32 flags = 0;
+	gss_buffer_desc in_buf, out_buf;
+	struct smb_tran_enc_state_gss *gss_state;
+	DATA_BLOB auth_reply = data_blob_null;
+	DATA_BLOB response = data_blob_null;
+	NTSTATUS status;
+
+	if (!partial_srv_trans_enc_ctx) {
+		status = make_srv_encryption_context(SMB_TRANS_ENC_GSS, &partial_srv_trans_enc_ctx);
+		if (!NT_STATUS_IS_OK(status)) {
+			return status;
+		}
+	}
+
+	gss_state = partial_srv_trans_enc_ctx->es->s.gss_state;
+
+	in_buf.value = secblob.data;
+	in_buf.length = secblob.length;
+
+	out_buf.value = NULL;
+	out_buf.length = 0;
+
+	become_root();
+
+	ret = gss_accept_sec_context(&min,
+				&gss_state->gss_ctx,
+				gss_state->creds,
+				&in_buf,
+				GSS_C_NO_CHANNEL_BINDINGS,
+				NULL,
+				NULL,		/* Ignore oids. */
+				&out_buf,	/* To return. */
+				&flags,
+				NULL,		/* Ingore time. */
+				NULL);		/* Ignore delegated creds. */
+	unbecome_root();
+
+	status = gss_err_to_ntstatus(ret, min);
+	if (ret != GSS_S_COMPLETE && ret != GSS_S_CONTINUE_NEEDED) {
+		return status;
+	}
+
+	/* Ensure we've got sign+seal available. */
+	if (ret == GSS_S_COMPLETE) {
+		if ((flags & (GSS_C_INTEG_FLAG|GSS_C_CONF_FLAG|GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) !=
+				(GSS_C_INTEG_FLAG|GSS_C_CONF_FLAG|GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) {
+			DEBUG(0,("srv_enc_spnego_gss_negotiate: quality of service not good enough "
+				"for SMB sealing.\n"));
+			gss_release_buffer(&min, &out_buf);
+			return NT_STATUS_ACCESS_DENIED;
+		}
+	}
+
+	auth_reply = data_blob(out_buf.value, out_buf.length);
+	gss_release_buffer(&min, &out_buf);
+
+	/* Wrap in SPNEGO. */
+	response = spnego_gen_auth_response(&auth_reply, status, OID_KERBEROS5);
+	data_blob_free(&auth_reply);
+
+	SAFE_FREE(*ppdata);
+	*ppdata = response.data;
+	*p_data_size = response.length;
+
+	return status;
+}
+#endif
+
+/******************************************************************************
+ Do the NTLM SPNEGO (or raw) encryption negotiation. Parameters are in/out.
+ Until success we do everything on the partial enc ctx.
+******************************************************************************/
+
+static NTSTATUS srv_enc_ntlm_negotiate(unsigned char **ppdata, size_t *p_data_size, DATA_BLOB secblob, bool spnego_wrap)
+{
+	NTSTATUS status;
+	DATA_BLOB chal = data_blob_null;
+	DATA_BLOB response = data_blob_null;
+
+	status = make_srv_encryption_context(SMB_TRANS_ENC_NTLM, &partial_srv_trans_enc_ctx);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+
+	status = auth_ntlmssp_update(partial_srv_trans_enc_ctx->auth_ntlmssp_state, secblob, &chal);
+
+	/* status here should be NT_STATUS_MORE_PROCESSING_REQUIRED
+	 * for success ... */
+
+	if (spnego_wrap) {
+		response = spnego_gen_auth_response(&chal, status, OID_NTLMSSP);
+		data_blob_free(&chal);
+	} else {
+		/* Return the raw blob. */
+		response = chal;
+	}
+
+	SAFE_FREE(*ppdata);
+	*ppdata = response.data;
+	*p_data_size = response.length;
+	return status;
+}
+
+/******************************************************************************
+ Do the SPNEGO encryption negotiation. Parameters are in/out.
+ Based off code in smbd/sesssionsetup.c
+ Until success we do everything on the partial enc ctx.
+******************************************************************************/
+
+static NTSTATUS srv_enc_spnego_negotiate(connection_struct *conn,
+					unsigned char **ppdata,
+					size_t *p_data_size,
+					unsigned char **pparam,
+					size_t *p_param_size)
+{
+	NTSTATUS status;
+	DATA_BLOB blob = data_blob_null;
+	DATA_BLOB secblob = data_blob_null;
+	bool got_kerberos_mechanism = false;
+
+	blob = data_blob_const(*ppdata, *p_data_size);
+
+	status = parse_spnego_mechanisms(blob, &secblob, &got_kerberos_mechanism);
+	if (!NT_STATUS_IS_OK(status)) {
+		return nt_status_squash(status);
+	}
+
+	/* We should have no partial context at this point. */
+
+	srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+
+#if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
+	if (got_kerberos_mechanism && lp_use_kerberos_keytab() ) {
+		status = srv_enc_spnego_gss_negotiate(ppdata, p_data_size, secblob);
+	} else 
+#endif
+	{
+		status = srv_enc_ntlm_negotiate(ppdata, p_data_size, secblob, true);
+	}
+
+	data_blob_free(&secblob);
+
+	if (!NT_STATUS_EQUAL(status,NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(status)) {
+		srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+		return nt_status_squash(status);
+	}
+
+	if (NT_STATUS_IS_OK(status)) {
+		/* Return the context we're using for this encryption state. */
+		if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
+			return NT_STATUS_NO_MEMORY;
+		}
+		SSVAL(*pparam,0,partial_srv_trans_enc_ctx->es->enc_ctx_num);
+		*p_param_size = 2;
+	}
+
+	return status;
+}
+
+/******************************************************************************
+ Complete a SPNEGO encryption negotiation. Parameters are in/out.
+ We only get this for a NTLM auth second stage.
+******************************************************************************/
+
+static NTSTATUS srv_enc_spnego_ntlm_auth(connection_struct *conn,
+					unsigned char **ppdata,
+					size_t *p_data_size,
+					unsigned char **pparam,
+					size_t *p_param_size)
+{
+	NTSTATUS status;
+	DATA_BLOB blob = data_blob_null;
+	DATA_BLOB auth = data_blob_null;
+	DATA_BLOB auth_reply = data_blob_null;
+	DATA_BLOB response = data_blob_null;
+	struct smb_srv_trans_enc_ctx *ec = partial_srv_trans_enc_ctx;
+
+	/* We must have a partial context here. */
+
+	if (!ec || !ec->es || ec->auth_ntlmssp_state == NULL || ec->es->smb_enc_type != SMB_TRANS_ENC_NTLM) {
+		srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	blob = data_blob_const(*ppdata, *p_data_size);
+	if (!spnego_parse_auth(blob, &auth)) {
+		srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	status = auth_ntlmssp_update(ec->auth_ntlmssp_state, auth, &auth_reply);
+	data_blob_free(&auth);
+
+	response = spnego_gen_auth_response(&auth_reply, status, OID_NTLMSSP);
+	data_blob_free(&auth_reply);
+
+	if (NT_STATUS_IS_OK(status)) {
+		/* Return the context we're using for this encryption state. */
+		if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
+			return NT_STATUS_NO_MEMORY;
+		}
+		SSVAL(*pparam,0,ec->es->enc_ctx_num);
+		*p_param_size = 2;
+	}
+
+	SAFE_FREE(*ppdata);
+	*ppdata = response.data;
+	*p_data_size = response.length;
+	return status;
+}
+
+/******************************************************************************
+ Raw NTLM encryption negotiation. Parameters are in/out.
+ This function does both steps.
+******************************************************************************/
+
+static NTSTATUS srv_enc_raw_ntlm_auth(connection_struct *conn,
+					unsigned char **ppdata,
+					size_t *p_data_size,
+					unsigned char **pparam,
+					size_t *p_param_size)
+{
+	NTSTATUS status;
+	DATA_BLOB blob = data_blob_const(*ppdata, *p_data_size);
+	DATA_BLOB response = data_blob_null;
+	struct smb_srv_trans_enc_ctx *ec;
+
+	if (!partial_srv_trans_enc_ctx) {
+		/* This is the initial step. */
+		status = srv_enc_ntlm_negotiate(ppdata, p_data_size, blob, false);
+		if (!NT_STATUS_EQUAL(status,NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(status)) {
+			srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+			return nt_status_squash(status);
+		}
+		return status;
+	}
+
+	ec = partial_srv_trans_enc_ctx;
+	if (!ec || !ec->es || ec->auth_ntlmssp_state == NULL || ec->es->smb_enc_type != SMB_TRANS_ENC_NTLM) {
+		srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	/* Second step. */
+	status = auth_ntlmssp_update(partial_srv_trans_enc_ctx->auth_ntlmssp_state, blob, &response);
+
+	if (NT_STATUS_IS_OK(status)) {
+		/* Return the context we're using for this encryption state. */
+		if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
+			return NT_STATUS_NO_MEMORY;
+		}
+		SSVAL(*pparam,0,ec->es->enc_ctx_num);
+		*p_param_size = 2;
+	}
+
+	/* Return the raw blob. */
+	SAFE_FREE(*ppdata);
+	*ppdata = response.data;
+	*p_data_size = response.length;
+	return status;
+}
+
+/******************************************************************************
+ Do the SPNEGO encryption negotiation. Parameters are in/out.
+******************************************************************************/
+
+NTSTATUS srv_request_encryption_setup(connection_struct *conn,
+					unsigned char **ppdata,
+					size_t *p_data_size,
+					unsigned char **pparam,
+					size_t *p_param_size)
+{
+	unsigned char *pdata = *ppdata;
+
+	SAFE_FREE(*pparam);
+	*p_param_size = 0;
+
+	if (*p_data_size < 1) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (pdata[0] == ASN1_APPLICATION(0)) {
+		/* its a negTokenTarg packet */
+		return srv_enc_spnego_negotiate(conn, ppdata, p_data_size, pparam, p_param_size);
+	}
+
+	if (pdata[0] == ASN1_CONTEXT(1)) {
+		/* It's an auth packet */
+		return srv_enc_spnego_ntlm_auth(conn, ppdata, p_data_size, pparam, p_param_size);
+	}
+
+	/* Maybe it's a raw unwrapped auth ? */
+	if (*p_data_size < 7) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+
+	if (strncmp((char *)pdata, "NTLMSSP", 7) == 0) {
+		return srv_enc_raw_ntlm_auth(conn, ppdata, p_data_size, pparam, p_param_size);
+	}
+
+	DEBUG(1,("srv_request_encryption_setup: Unknown packet\n"));
+
+	return NT_STATUS_LOGON_FAILURE;
+}
+
+/******************************************************************************
+ Negotiation was successful - turn on server-side encryption.
+******************************************************************************/
+
+static NTSTATUS check_enc_good(struct smb_srv_trans_enc_ctx *ec)
+{
+	if (!ec || !ec->es) {
+		return NT_STATUS_LOGON_FAILURE;
+	}
+
+	if (ec->es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
+		if ((ec->es->s.ntlmssp_state->neg_flags & (NTLMSSP_NEGOTIATE_SIGN|NTLMSSP_NEGOTIATE_SEAL)) !=
+				(NTLMSSP_NEGOTIATE_SIGN|NTLMSSP_NEGOTIATE_SEAL)) {
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+	}
+	/* Todo - check gssapi case. */
+
+	return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Negotiation was successful - turn on server-side encryption.
+******************************************************************************/
+
+NTSTATUS srv_encryption_start(connection_struct *conn)
+{
+	NTSTATUS status;
+
+	/* Check that we are really doing sign+seal. */
+	status = check_enc_good(partial_srv_trans_enc_ctx);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	/* Throw away the context we're using currently (if any). */
+	srv_free_encryption_context(&srv_trans_enc_ctx);
+
+	/* Steal the partial pointer. Deliberate shallow copy. */
+	srv_trans_enc_ctx = partial_srv_trans_enc_ctx;
+	srv_trans_enc_ctx->es->enc_on = true;
+
+	partial_srv_trans_enc_ctx = NULL;
+	return NT_STATUS_OK;
+}
+
+/******************************************************************************
+ Shutdown all server contexts.
+******************************************************************************/
+
+void server_encryption_shutdown(void)
+{
+	srv_free_encryption_context(&partial_srv_trans_enc_ctx);
+	srv_free_encryption_context(&srv_trans_enc_ctx);
+}