/* 
   Unix SMB/CIFS implementation.

   dcerpc utility functions

   Copyright (C) Andrew Tridgell 2003
   
   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"

/*
  this ndr_size_* stuff should really be auto-generated ....
*/

static size_t ndr_size_epm_floor(struct epm_floor *fl)
{
	size_t ret = 5;
	if (fl->lhs.protocol == EPM_PROTOCOL_UUID) {
		ret += 18;
	} else {
		ret += fl->lhs.info.lhs_data.length;
	}
	ret += fl->rhs.rhs_data.length;
	return ret;
}

size_t ndr_size_epm_towers(struct epm_towers *towers)
{
	size_t ret = 2;
	int i;
	for (i=0;i<towers->num_floors;i++) {
		ret += ndr_size_epm_floor(&towers->floors[i]);
	}
	return ret;
}

/*
  work out what TCP port to use for a given interface on a given host
*/
NTSTATUS dcerpc_epm_map_tcp_port(const char *server, 
				 const char *uuid, unsigned version,
				 uint32 *port)
{
	struct dcerpc_pipe *p;
	NTSTATUS status;
	struct epm_Map r;
	struct policy_handle handle;
	struct GUID guid;
	struct epm_twr_t twr, *twr_r;

	if (strcasecmp(uuid, DCERPC_EPMAPPER_UUID) == 0 ||
	    strcasecmp(uuid, DCERPC_MGMT_UUID) == 0) {
		/* don't lookup epmapper via epmapper! */
		*port = EPMAPPER_PORT;
		return NT_STATUS_OK;
	}

	status = dcerpc_pipe_open_tcp(&p, server, EPMAPPER_PORT);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	/* we can use the pipes memory context here as we will have a short
	   lived connection */
	status = dcerpc_bind_byuuid(p, p->mem_ctx, 
				    DCERPC_EPMAPPER_UUID,
				    DCERPC_EPMAPPER_VERSION);
	if (!NT_STATUS_IS_OK(status)) {
		dcerpc_pipe_close(p);
		return status;
	}

	ZERO_STRUCT(handle);
	ZERO_STRUCT(guid);

	twr.towers.num_floors = 5;
	twr.towers.floors = talloc(p->mem_ctx, sizeof(twr.towers.floors[0]) * 5);

	/* what I'd like for christmas ... */

	/* an RPC interface ... */
	twr.towers.floors[0].lhs.protocol = EPM_PROTOCOL_UUID;
	GUID_from_string(uuid, &twr.towers.floors[0].lhs.info.uuid.uuid);
	twr.towers.floors[0].lhs.info.uuid.version = version;
	twr.towers.floors[0].rhs.rhs_data = data_blob_talloc_zero(p->mem_ctx, 2);

	/* encoded with NDR ... */
	twr.towers.floors[1].lhs.protocol = EPM_PROTOCOL_UUID;
	GUID_from_string(NDR_GUID, &twr.towers.floors[1].lhs.info.uuid.uuid);
	twr.towers.floors[1].lhs.info.uuid.version = NDR_GUID_VERSION;
	twr.towers.floors[1].rhs.rhs_data = data_blob_talloc_zero(p->mem_ctx, 2);

	/* on an RPC connection ... */
	twr.towers.floors[2].lhs.protocol = EPM_PROTOCOL_RPC_C;
	twr.towers.floors[2].lhs.info.lhs_data = data_blob(NULL, 0);
	twr.towers.floors[2].rhs.rhs_data = data_blob_talloc_zero(p->mem_ctx, 2);

	/* on a TCP port ... */
	twr.towers.floors[3].lhs.protocol = EPM_PROTOCOL_TCP;
	twr.towers.floors[3].lhs.info.lhs_data = data_blob(NULL, 0);
	twr.towers.floors[3].rhs.rhs_data = data_blob_talloc_zero(p->mem_ctx, 2);

	/* on an IP link ... */
	twr.towers.floors[4].lhs.protocol = EPM_PROTOCOL_IP;
	twr.towers.floors[4].lhs.info.lhs_data = data_blob(NULL, 0);
	twr.towers.floors[4].rhs.rhs_data = data_blob_talloc_zero(p->mem_ctx, 4);

	/* with some nice pretty paper around it of course */
	r.in.object = &guid;
	r.in.map_tower = &twr;
	r.in.entry_handle = &handle;
	r.in.max_towers = 1;
	r.out.entry_handle = &handle;

	status = dcerpc_epm_Map(p, p->mem_ctx, &r);
	if (!NT_STATUS_IS_OK(status)) {
		dcerpc_pipe_close(p);
		return status;
	}
	if (r.out.status != 0 || r.out.num_towers != 1) {
		dcerpc_pipe_close(p);
		return NT_STATUS_PORT_UNREACHABLE;
	}

	twr_r = r.out.towers[0].twr;
	if (!twr_r) {
		dcerpc_pipe_close(p);
		return NT_STATUS_PORT_UNREACHABLE;
	}

	if (twr_r->towers.num_floors != 5 ||
	    twr_r->towers.floors[3].lhs.protocol != twr.towers.floors[3].lhs.protocol ||
	    twr_r->towers.floors[3].rhs.rhs_data.length != 2) {
		dcerpc_pipe_close(p);
		return NT_STATUS_PORT_UNREACHABLE;
	}

	*port = RSVAL(twr_r->towers.floors[3].rhs.rhs_data.data, 0);

	dcerpc_pipe_close(p);

	return NT_STATUS_OK;
}


/*
  find the pipe name for a local IDL interface
*/
const char *idl_pipe_name(const char *uuid, uint32 if_version)
{
	int i;
	for (i=0;dcerpc_pipes[i];i++) {
		if (strcasecmp(dcerpc_pipes[i]->uuid, uuid) == 0 &&
		    dcerpc_pipes[i]->if_version == if_version) {
			return dcerpc_pipes[i]->name;
		}
	}
	return "UNKNOWN";
}

/*
  find the number of calls defined by local IDL
*/
int idl_num_calls(const char *uuid, uint32 if_version)
{
	int i;
	for (i=0;dcerpc_pipes[i];i++) {
		if (strcasecmp(dcerpc_pipes[i]->uuid, uuid) == 0 &&
		    dcerpc_pipes[i]->if_version == if_version) {
			return dcerpc_pipes[i]->num_calls;
		}
	}
	return -1;
}


/*
  find a dcerpc interface by name
*/
const struct dcerpc_interface_table *idl_iface_by_name(const char *name)
{
	int i;
	for (i=0;dcerpc_pipes[i];i++) {
		if (strcasecmp(dcerpc_pipes[i]->name, name) == 0) {
			return dcerpc_pipes[i];
		}
	}
	return NULL;
}

/*
  find a dcerpc interface by uuid
*/
const struct dcerpc_interface_table *idl_iface_by_uuid(const char *uuid)
{
	int i;
	for (i=0;dcerpc_pipes[i];i++) {
		if (strcasecmp(dcerpc_pipes[i]->uuid, uuid) == 0) {
			return dcerpc_pipes[i];
		}
	}
	return NULL;
}



/* 
   push a dcerpc_packet into a blob, potentially with auth info
*/
NTSTATUS dcerpc_push_auth(DATA_BLOB *blob, TALLOC_CTX *mem_ctx, 
			  struct dcerpc_packet *pkt,
			  struct dcerpc_auth *auth_info)
{
	NTSTATUS status;
	struct ndr_push *ndr;

	ndr = ndr_push_init_ctx(mem_ctx);
	if (!ndr) {
		return NT_STATUS_NO_MEMORY;
	}

	if (!(pkt->drep[0] & DCERPC_DREP_LE)) {
		ndr->flags |= LIBNDR_FLAG_BIGENDIAN;
	}

	if (auth_info) {
		pkt->auth_length = auth_info->credentials.length;
	} else {
		pkt->auth_length = 0;
	}

	status = ndr_push_dcerpc_packet(ndr, NDR_SCALARS|NDR_BUFFERS, pkt);
	if (!NT_STATUS_IS_OK(status)) {
		return status;
	}

	if (auth_info) {
		status = ndr_push_dcerpc_auth(ndr, NDR_SCALARS|NDR_BUFFERS, auth_info);
	}

	*blob = ndr_push_blob(ndr);

	/* fill in the frag length */
	dcerpc_set_frag_length(blob, blob->length);

	return NT_STATUS_OK;
}


static const struct {
	const char *name;
	enum dcerpc_transport_t transport;
} ncacn_transports[] = {
	{"ncacn_np",     NCACN_NP},
	{"ncacn_ip_tcp", NCACN_IP_TCP}
};

static const struct {
	const char *name;
	uint32 flag;
} ncacn_options[] = {
	{"sign", DCERPC_SIGN},
	{"seal", DCERPC_SEAL},
	{"schannel", DCERPC_SCHANNEL},
	{"validate", DCERPC_DEBUG_VALIDATE_BOTH},
	{"print", DCERPC_DEBUG_PRINT_BOTH},
	{"bigendian", DCERPC_PUSH_BIGENDIAN}
};

/*
  form a binding string from a binding structure
*/
const char *dcerpc_binding_string(TALLOC_CTX *mem_ctx, const struct dcerpc_binding *b)
{
	char *s = NULL;
	int i;
	const char *t_name=NULL;

	for (i=0;i<ARRAY_SIZE(ncacn_transports);i++) {
		if (ncacn_transports[i].transport == b->transport) {
			t_name = ncacn_transports[i].name;
		}
	}
	if (!t_name) {
		return NULL;
	}

	s = talloc_asprintf(mem_ctx, "%s:%s:[", t_name, b->host);
	if (!s) return NULL;

	/* this is a *really* inefficent way of dealing with strings,
	   but this is rarely called and the strings are always short,
	   so I don't care */
	for (i=0;b->options && b->options[i];i++) {
		s = talloc_asprintf(mem_ctx, "%s%s,", s, b->options[i]);
		if (!s) return NULL;
	}
	for (i=0;i<ARRAY_SIZE(ncacn_options);i++) {
		if (b->flags & ncacn_options[i].flag) {
			s = talloc_asprintf(mem_ctx, "%s%s,", s, ncacn_options[i].name);
			if (!s) return NULL;
		}
	}
	if (s[strlen(s)-1] == ',') {
		s[strlen(s)-1] = 0;
	}
	s = talloc_asprintf(mem_ctx, "%s]", s);

	return s;
}

/*
  parse a binding string into a dcerpc_binding structure
*/
NTSTATUS dcerpc_parse_binding(TALLOC_CTX *mem_ctx, const char *s, struct dcerpc_binding *b)
{
	char *part1, *part2, *part3;
	char *p;
	int i, j, comma_count;

	p = strchr(s, ':');
	if (!p) {
		return NT_STATUS_INVALID_PARAMETER;
	}
	part1 = talloc_strndup(mem_ctx, s, PTR_DIFF(p, s));
	if (!part1) {
		return NT_STATUS_NO_MEMORY;
	}
	s = p+1;

	p = strchr(s, ':');
	if (!p) {
		p = strchr(s, '[');
		if (p) {
			part2 = talloc_strndup(mem_ctx, s, PTR_DIFF(p, s));
			part3 = talloc_strdup(mem_ctx, p+1);
			if (part3[strlen(part3)-1] != ']') {
				return NT_STATUS_INVALID_PARAMETER;
			}
			part3[strlen(part3)-1] = 0;
		} else {
			part2 = talloc_strdup(mem_ctx, s);
			part3 = NULL;
		}
	} else {
		part2 = talloc_strndup(mem_ctx, s, PTR_DIFF(p, s));
		part3 = talloc_strdup(mem_ctx, p+1);
	}
	if (!part2) {
		return NT_STATUS_NO_MEMORY;
	}

	for (i=0;i<ARRAY_SIZE(ncacn_transports);i++) {
		if (strcasecmp(part1, ncacn_transports[i].name) == 0) {
			b->transport = ncacn_transports[i].transport;
			break;
		}
	}
	if (i==ARRAY_SIZE(ncacn_transports)) {
		DEBUG(0,("Unknown dcerpc transport '%s'\n", part1));
		return NT_STATUS_INVALID_PARAMETER;
	}

	b->host = part2;
	b->options = NULL;
	b->flags = 0;

	if (!part3) {
		return NT_STATUS_OK;
	}

	/* the [] brackets are optional */
	if (*part3 == '[' && part3[strlen(part3)-1] == ']') {
		part3++;
		part3[strlen(part3)-1] = 0;
	}

	comma_count = count_chars(part3, ',');
	b->options = talloc_array_p(mem_ctx, const char *, comma_count+2);
	if (!b->options) {
		return NT_STATUS_NO_MEMORY;
	}

	for (i=0; (p = strchr(part3, ',')); i++) {
		b->options[i] = talloc_strndup(mem_ctx, part3, PTR_DIFF(p, part3));
		if (!b->options[i]) {
			return NT_STATUS_NO_MEMORY;
		}
		part3 = p+1;
	}
	b->options[i] = part3;
	b->options[i+1] = NULL;

	/* some options are pre-parsed for convenience */
	for (i=0;b->options[i];i++) {
		for (j=0;j<ARRAY_SIZE(ncacn_options);j++) {
			if (strcasecmp(ncacn_options[j].name, b->options[i]) == 0) {
				int k;
				b->flags |= ncacn_options[j].flag;
				for (k=i;b->options[k];k++) {
					b->options[k] = b->options[k+1];
				}
				i--;
				break;
			}
		}
	}
	
	return NT_STATUS_OK;
}


/* open a rpc connection to a rpc pipe on SMB using the binding
   structure to determine the endpoint and options */
static NTSTATUS dcerpc_pipe_connect_ncacn_np(struct dcerpc_pipe **p, 
					     struct dcerpc_binding *binding,
					     const char *pipe_uuid, 
					     uint32 pipe_version,
					     const char *domain,
					     const char *username,
					     const char *password)
{
	NTSTATUS status;
	BOOL retry;
	struct cli_state *cli;
	const char *pipe_name;
	
	if (!binding->options || !binding->options[0]) {
		const struct dcerpc_interface_table *table = idl_iface_by_uuid(pipe_uuid);
		if (!table) {
			DEBUG(0,("Unknown interface endpoint '%s'\n", pipe_uuid));
			return NT_STATUS_INVALID_PARAMETER;
		}
		/* only try the first endpoint for now */
		pipe_name = table->endpoints->names[0];
	} else {
		pipe_name = binding->options[0];
	}

	if (strncasecmp(pipe_name, "\\pipe\\", 6) == 0) {
		pipe_name += 6;
	}
	if (strncasecmp(pipe_name, "/pipe/", 6) == 0) {
		pipe_name += 6;
	}
	    
	status = cli_full_connection(&cli, lp_netbios_name(),
				     binding->host, NULL, 
				     "ipc$", "?????", 
				     username, username[0]?domain:"",
				     password, 0, &retry);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("Failed to connect to %s - %s\n", binding->host, nt_errstr(status)));
		return status;
	}

	status = dcerpc_pipe_open_smb(p, cli->tree, pipe_name);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("Failed to open pipe %s - %s\n", pipe_name, nt_errstr(status)));
		cli_tdis(cli);
		cli_shutdown(cli);
                return status;
        }
	
	/* this ensures that the reference count is decremented so
	   a pipe close will really close the link */
	cli_tree_close(cli->tree);
	
	(*p)->flags = binding->flags;

	if (binding->flags & DCERPC_SCHANNEL) {
		const char *trust_password = secrets_fetch_machine_password();
		if (!trust_password) {
			DEBUG(0,("Unable to fetch machine password\n"));
			goto done;
		}
		status = dcerpc_bind_auth_schannel(*p, pipe_uuid, pipe_version, 
						   lp_workgroup(), 
						   lp_netbios_name(), 
						   trust_password);
	} else if (binding->flags & (DCERPC_SIGN | DCERPC_SEAL)) {
		status = dcerpc_bind_auth_ntlm(*p, pipe_uuid, pipe_version, domain, username, password);
	} else {    
		status = dcerpc_bind_auth_none(*p, pipe_uuid, pipe_version);
	}

done:
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("Failed to bind to uuid %s - %s\n", pipe_uuid, nt_errstr(status)));
		dcerpc_pipe_close(*p);
		return status;
	}

	return NT_STATUS_OK;
}


/* open a rpc connection to a rpc pipe on SMP using the binding
   structure to determine the endpoint and options */
static NTSTATUS dcerpc_pipe_connect_ncacn_ip_tcp(struct dcerpc_pipe **p, 
						 struct dcerpc_binding *binding,
						 const char *pipe_uuid, 
						 uint32 pipe_version,
						 const char *domain,
						 const char *username,
						 const char *password)
{
	NTSTATUS status;
	uint32 port = 0;

	if (binding->options && binding->options[0]) {
		port = atoi(binding->options[0]);
	}

	if (port == 0) {
		status = dcerpc_epm_map_tcp_port(binding->host, 
						 pipe_uuid, pipe_version,
						 &port);
		if (!NT_STATUS_IS_OK(status)) {
			DEBUG(0,("Failed to map DCERPC/TCP port for '%s' - %s\n", 
				 pipe_uuid, nt_errstr(status)));
			return status;
		}
		DEBUG(1,("Mapped to DCERPC/TCP port %u\n", port));
	}

	status = dcerpc_pipe_open_tcp(p, binding->host, port);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("Failed to connect to %s:%d\n", binding->host, port));
                return status;
        }

	/* it doesn't seem to work to do a null NTLMSSP session without either sign
	   or seal, so force signing if we are doing ntlmssp */
	if (username[0] && !(binding->flags & (DCERPC_SIGN|DCERPC_SEAL))) {
		binding->flags |= DCERPC_SIGN;
	}

	(*p)->flags = binding->flags;

	if (!(binding->flags & (DCERPC_SIGN|DCERPC_SEAL)) && !username[0]) {
		status = dcerpc_bind_auth_none(*p, pipe_uuid, pipe_version);
	} else {
		status = dcerpc_bind_auth_ntlm(*p, pipe_uuid, pipe_version,
					       domain, username, password);
	}

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("Failed to bind to uuid %s - %s\n", pipe_uuid, nt_errstr(status)));
		dcerpc_pipe_close(*p);
		return status;
	}
 
        return status;
}


/* open a rpc connection to a rpc pipe, using the specified 
   binding structure to determine the endpoint and options */
NTSTATUS dcerpc_pipe_connect_b(struct dcerpc_pipe **p, 
			       struct dcerpc_binding *binding,
			       const char *pipe_uuid, 
			       uint32 pipe_version,
			       const char *domain,
			       const char *username,
			       const char *password)
{
	NTSTATUS status = NT_STATUS_INVALID_PARAMETER;

	switch (binding->transport) {
	case NCACN_NP:
		status = dcerpc_pipe_connect_ncacn_np(p, binding, pipe_uuid, pipe_version,
						      domain, username, password);
		break;
	case NCACN_IP_TCP:
		status = dcerpc_pipe_connect_ncacn_ip_tcp(p, binding, pipe_uuid, pipe_version,
							  domain, username, password);
		break;
	}

	/* remember the binding string for possible secondary connections */
	if (NT_STATUS_IS_OK(status)) {
		(*p)->binding_string = dcerpc_binding_string((*p)->mem_ctx, binding);
	}

	return status;
}


/* open a rpc connection to a rpc pipe, using the specified string
   binding to determine the endpoint and options */
NTSTATUS dcerpc_pipe_connect(struct dcerpc_pipe **p, 
			     const char *binding,
			     const char *pipe_uuid, 
			     uint32 pipe_version,
			     const char *domain,
			     const char *username,
			     const char *password)
{
	struct dcerpc_binding b;
	NTSTATUS status;
	TALLOC_CTX *mem_ctx;

	mem_ctx = talloc_init("dcerpc_pipe_connect");
	if (!mem_ctx) return NT_STATUS_NO_MEMORY;

	status = dcerpc_parse_binding(mem_ctx, binding, &b);
	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(0,("Failed to parse dcerpc binding '%s'\n", binding));
		talloc_destroy(mem_ctx);
		return status;
	}

	DEBUG(3,("Using binding %s\n", dcerpc_binding_string(mem_ctx, &b)));

	status = dcerpc_pipe_connect_b(p, &b, pipe_uuid, pipe_version, domain, username, password);

	talloc_destroy(mem_ctx);
	return status;
}


/*
  create a secondary dcerpc connection on SMB
  the secondary connection will be on the same SMB connection, but
  use a new fnum
*/
NTSTATUS dcerpc_secondary_smb(struct dcerpc_pipe *p, struct dcerpc_pipe **p2,
			      const char *pipe_name,
			      const char *pipe_uuid,
			      uint32 pipe_version)
{
	NTSTATUS status;
	struct cli_tree *tree;

	tree = dcerpc_smb_tree(p);
	if (!tree) {
		return NT_STATUS_INVALID_PARAMETER;
	}

	status = dcerpc_pipe_open_smb(p2, tree, pipe_name);
	if (!NT_STATUS_IS_OK(status)) {
                return status;
        }
	
	(*p2)->flags = p->flags;

	status = dcerpc_bind_auth_none(*p2, pipe_uuid, pipe_version);
	if (!NT_STATUS_IS_OK(status)) {
                return status;
        }

	return NT_STATUS_OK;
}


/*
  fetch the user session key for the underlying transport. Currently
  only works for the ncacn_np transport
*/
NTSTATUS dcerpc_fetch_session_key(struct dcerpc_pipe *p,
				  DATA_BLOB *session_key)
{
	struct cli_tree *tree;

	if (p->security_state) {
		return p->security_state->session_key(p->security_state, session_key);
	}
	
	tree = dcerpc_smb_tree(p);
	if (tree) {
		if (tree->session->user_session_key.data) {
			*session_key = tree->session->user_session_key;
			return NT_STATUS_OK;
		}
	}

	return NT_STATUS_NO_USER_SESSION_KEY;
}