/* 
   Unix SMB/CIFS implementation.

   Async helpers for blocking functions

   Copyright (C) Volker Lendecke 2005
   Copyright (C) Gerald Carter 2006

   The helpers always consist of three functions: 

   * A request setup function that takes the necessary parameters together
     with a continuation function that is to be called upon completion

   * A private continuation function that is internal only. This is to be
     called by the lower-level functions in do_async(). Its only task is to
     properly call the continuation function named above.

   * A worker function that is called inside the appropriate child process.

   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 "winbindd.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_WINBIND

struct do_async_state {
	TALLOC_CTX *mem_ctx;
	struct winbindd_request request;
	struct winbindd_response response;
	void (*cont)(TALLOC_CTX *mem_ctx,
		     bool success,
		     struct winbindd_response *response,
		     void *c, void *private_data);
	void *c, *private_data;
};

static void do_async_recv(void *private_data, bool success)
{
	struct do_async_state *state =
		talloc_get_type_abort(private_data, struct do_async_state);

	state->cont(state->mem_ctx, success, &state->response,
		    state->c, state->private_data);
}

void do_async(TALLOC_CTX *mem_ctx, struct winbindd_child *child,
	      const struct winbindd_request *request,
	      void (*cont)(TALLOC_CTX *mem_ctx, bool success,
			   struct winbindd_response *response,
			   void *c, void *private_data),
	      void *c, void *private_data)
{
	struct do_async_state *state;

	state = TALLOC_ZERO_P(mem_ctx, struct do_async_state);
	if (state == NULL) {
		DEBUG(0, ("talloc failed\n"));
		cont(mem_ctx, False, NULL, c, private_data);
		return;
	}

	state->mem_ctx = mem_ctx;
	state->request = *request;
	state->request.length = sizeof(state->request);
	state->cont = cont;
	state->c = c;
	state->private_data = private_data;

	async_request(mem_ctx, child, &state->request,
		      &state->response, do_async_recv, state);
}

static void do_async_domain(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
			    const struct winbindd_request *request,
			    void (*cont)(TALLOC_CTX *mem_ctx, bool success,
					 struct winbindd_response *response,
					 void *c, void *private_data),
			    void *c, void *private_data)
{
	struct do_async_state *state;

	state = TALLOC_ZERO_P(mem_ctx, struct do_async_state);
	if (state == NULL) {
		DEBUG(0, ("talloc failed\n"));
		cont(mem_ctx, False, NULL, c, private_data);
		return;
	}

	state->mem_ctx = mem_ctx;
	state->request = *request;
	state->request.length = sizeof(state->request);
	state->cont = cont;
	state->c = c;
	state->private_data = private_data;

	async_domain_request(mem_ctx, domain, &state->request,
			     &state->response, do_async_recv, state);
}

struct lookupsid_state {
	DOM_SID sid;	
	void *caller_private_data;
};


static void lookupsid_recv2(TALLOC_CTX *mem_ctx, bool success,
			   struct winbindd_response *response,
			   void *c, void *private_data)
{
	void (*cont)(void *priv, bool succ, const char *dom_name,
		     const char *name, enum lsa_SidType type) =
		(void (*)(void *, bool, const char *, const char *,
			  enum lsa_SidType))c;
	struct lookupsid_state *s = talloc_get_type_abort(private_data, 
							  struct lookupsid_state);

	if (!success) {
		DEBUG(5, ("Could not trigger lookupsid\n"));
		cont(s->caller_private_data, False, NULL, NULL, SID_NAME_UNKNOWN);
		return;
	}

	if (response->result != WINBINDD_OK) {
		DEBUG(5, ("lookupsid (forest root) returned an error\n"));		
		cont(s->caller_private_data, False, NULL, NULL, SID_NAME_UNKNOWN);
		return;
	}

	cont(s->caller_private_data, True, response->data.name.dom_name,
	     response->data.name.name,
	     (enum lsa_SidType)response->data.name.type);
}

static void lookupsid_recv(TALLOC_CTX *mem_ctx, bool success,
			   struct winbindd_response *response,
			   void *c, void *private_data)
{
	void (*cont)(void *priv, bool succ, const char *dom_name,
		     const char *name, enum lsa_SidType type) =
		(void (*)(void *, bool, const char *, const char *,
			  enum lsa_SidType))c;
	struct lookupsid_state *s = talloc_get_type_abort(private_data, 
							  struct lookupsid_state);

	if (!success) {
		DEBUG(5, ("Could not trigger lookupsid\n"));
		cont(s->caller_private_data, False, NULL, NULL, SID_NAME_UNKNOWN);
		return;
	}

	if (response->result != WINBINDD_OK) {
		/* Try again using the forest root */
		struct winbindd_domain *root_domain = find_root_domain();
		struct winbindd_request request;

		if ( !root_domain ) {
			DEBUG(5,("lookupsid_recv: unable to determine forest root\n"));
			cont(s->caller_private_data, False, NULL, NULL, SID_NAME_UNKNOWN);
			return;
		}

		ZERO_STRUCT(request);
		request.cmd = WINBINDD_LOOKUPSID;
		sid_to_fstring(request.data.sid, &s->sid);

		do_async_domain(mem_ctx, root_domain, &request, lookupsid_recv2,
				(void *)cont, s);

		return;
	}

	cont(s->caller_private_data, True, response->data.name.dom_name,
	     response->data.name.name,
	     (enum lsa_SidType)response->data.name.type);
}

void winbindd_lookupsid_async(TALLOC_CTX *mem_ctx, const DOM_SID *sid,
			      void (*cont)(void *private_data, bool success,
					   const char *dom_name,
					   const char *name,
					   enum lsa_SidType type),
			      void *private_data)
{
	struct winbindd_domain *domain;
	struct winbindd_request request;
	struct lookupsid_state *s;	

	domain = find_lookup_domain_from_sid(sid);
	if (domain == NULL) {
		DEBUG(5, ("Could not find domain for sid %s\n",
			  sid_string_dbg(sid)));
		cont(private_data, False, NULL, NULL, SID_NAME_UNKNOWN);
		return;
	}

	ZERO_STRUCT(request);
	request.cmd = WINBINDD_LOOKUPSID;
	sid_to_fstring(request.data.sid, sid);

	if ( (s = TALLOC_ZERO_P(mem_ctx, struct lookupsid_state)) == NULL ) {
		DEBUG(0, ("winbindd_lookupsid_async: talloc failed\n"));
		cont(private_data, False, NULL, NULL, SID_NAME_UNKNOWN);
		return;
	}

	sid_copy( &s->sid, sid );	
	s->caller_private_data = private_data;	

	do_async_domain(mem_ctx, domain, &request, lookupsid_recv,
			(void *)cont, s);
}

enum winbindd_result winbindd_dual_lookupsid(struct winbindd_domain *domain,
					     struct winbindd_cli_state *state)
{
	enum lsa_SidType type;
	DOM_SID sid;
	char *name;
	char *dom_name;

	/* Ensure null termination */
	state->request->data.sid[sizeof(state->request->data.sid)-1]='\0';

	DEBUG(3, ("[%5lu]: lookupsid %s\n", (unsigned long)state->pid, 
		  state->request->data.sid));

	/* Lookup sid from PDC using lsa_lookup_sids() */

	if (!string_to_sid(&sid, state->request->data.sid)) {
		DEBUG(5, ("%s not a SID\n", state->request->data.sid));
		return WINBINDD_ERROR;
	}

	/* Lookup the sid */

	if (!winbindd_lookup_name_by_sid(state->mem_ctx, domain, &sid, 
					 &dom_name, &name, &type)) 
	{
		TALLOC_FREE(dom_name);
		TALLOC_FREE(name);
		return WINBINDD_ERROR;
	}

	fstrcpy(state->response->data.name.dom_name, dom_name);
	fstrcpy(state->response->data.name.name, name);
	state->response->data.name.type = type;

	TALLOC_FREE(dom_name);
	TALLOC_FREE(name);
	return WINBINDD_OK;
}

/********************************************************************
 This is the second callback after contacting the forest root
********************************************************************/

struct lookupname_state {
	char *dom_name;
	char *name;
	void *caller_private_data;
};


static void lookupname_recv2(TALLOC_CTX *mem_ctx, bool success,
			    struct winbindd_response *response,
			    void *c, void *private_data)
{
	void (*cont)(void *priv, bool succ, const DOM_SID *sid,
		     enum lsa_SidType type) =
		(void (*)(void *, bool, const DOM_SID *, enum lsa_SidType))c;
	DOM_SID sid;
	struct lookupname_state *s = talloc_get_type_abort( private_data,
							    struct lookupname_state );

	if (!success) {
		DEBUG(5, ("Could not trigger lookup_name\n"));
		cont(s->caller_private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	if (response->result != WINBINDD_OK) {
		DEBUG(5, ("lookup_name returned an error\n"));
		cont(s->caller_private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	if (!string_to_sid(&sid, response->data.sid.sid)) {
		DEBUG(0, ("Could not convert string %s to sid\n",
			  response->data.sid.sid));
		cont(s->caller_private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	cont(s->caller_private_data, True, &sid,
	     (enum lsa_SidType)response->data.sid.type);
}

/********************************************************************
 This is the first callback after contacting our own domain
********************************************************************/

static void lookupname_recv(TALLOC_CTX *mem_ctx, bool success,
			    struct winbindd_response *response,
			    void *c, void *private_data)
{
	void (*cont)(void *priv, bool succ, const DOM_SID *sid,
		     enum lsa_SidType type) =
		(void (*)(void *, bool, const DOM_SID *, enum lsa_SidType))c;
	DOM_SID sid;
	struct lookupname_state *s = talloc_get_type_abort( private_data,
							    struct lookupname_state );	

	if (!success) {
		DEBUG(5, ("lookupname_recv: lookup_name() failed!\n"));
		cont(s->caller_private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	if (response->result != WINBINDD_OK) {
		/* Try again using the forest root */
		struct winbindd_domain *root_domain = find_root_domain();
		struct winbindd_request request;

		if ( !root_domain ) {
			DEBUG(5,("lookupname_recv: unable to determine forest root\n"));
			cont(s->caller_private_data, False, NULL, SID_NAME_UNKNOWN);
			return;
		}

		ZERO_STRUCT(request);
		request.cmd = WINBINDD_LOOKUPNAME;

		fstrcpy( request.data.name.dom_name, s->dom_name );
		fstrcpy( request.data.name.name, s->name );

		do_async_domain(mem_ctx, root_domain, &request, lookupname_recv2,
				(void *)cont, s);

		return;
	}

	if (!string_to_sid(&sid, response->data.sid.sid)) {
		DEBUG(0, ("Could not convert string %s to sid\n",
			  response->data.sid.sid));
		cont(s->caller_private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	cont(s->caller_private_data, True, &sid,
	     (enum lsa_SidType)response->data.sid.type);
}

/********************************************************************
 The lookup name call first contacts a DC in its own domain
 and fallbacks to contact a DC if the forest in our domain doesn't
 know the name.
********************************************************************/

void winbindd_lookupname_async(TALLOC_CTX *mem_ctx,
			       const char *dom_name, const char *name,
			       void (*cont)(void *private_data, bool success,
					    const DOM_SID *sid,
					    enum lsa_SidType type),
			       enum winbindd_cmd orig_cmd,
			       void *private_data)
{
	struct winbindd_request request;
	struct winbindd_domain *domain;
	struct lookupname_state *s;

	domain = find_lookup_domain_from_name(dom_name);
	if (domain == NULL) {
		DEBUG(5, ("Could not find domain for name '%s'\n", dom_name));
		cont(private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	ZERO_STRUCT(request);
	request.cmd = WINBINDD_LOOKUPNAME;
	request.original_cmd = orig_cmd;
	fstrcpy(request.data.name.dom_name, dom_name);
	fstrcpy(request.data.name.name, name);

	if ( (s = TALLOC_ZERO_P(mem_ctx, struct lookupname_state)) == NULL ) {
		DEBUG(0, ("winbindd_lookupname_async: talloc failed\n"));
		cont(private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	s->dom_name = talloc_strdup( s, dom_name );
	s->name     = talloc_strdup( s, name );
	if (!s->dom_name || !s->name) {
		cont(private_data, False, NULL, SID_NAME_UNKNOWN);
		return;
	}

	s->caller_private_data = private_data;

	do_async_domain(mem_ctx, domain, &request, lookupname_recv,
			(void *)cont, s);
}

enum winbindd_result winbindd_dual_lookupname(struct winbindd_domain *domain,
					      struct winbindd_cli_state *state)
{
	enum lsa_SidType type;
	char *name_domain, *name_user;
	DOM_SID sid;
	char *p;

	/* Ensure null termination */
	state->request->data.name.dom_name[sizeof(state->request->data.name.dom_name)-1]='\0';

	/* Ensure null termination */
	state->request->data.name.name[sizeof(state->request->data.name.name)-1]='\0';

	/* cope with the name being a fully qualified name */
	p = strstr(state->request->data.name.name, lp_winbind_separator());
	if (p) {
		*p = 0;
		name_domain = state->request->data.name.name;
		name_user = p+1;
	} else {
		name_domain = state->request->data.name.dom_name;
		name_user = state->request->data.name.name;
	}

	DEBUG(3, ("[%5lu]: lookupname %s%s%s\n", (unsigned long)state->pid,
		  name_domain, lp_winbind_separator(), name_user));

	/* Lookup name from DC using lsa_lookup_names() */
	if (!winbindd_lookup_sid_by_name(state->mem_ctx, state->request->original_cmd, domain, name_domain,
					 name_user, &sid, &type)) {
		return WINBINDD_ERROR;
	}

	sid_to_fstring(state->response->data.sid.sid, &sid);
	state->response->data.sid.type = type;

	return WINBINDD_OK;
}

bool print_sidlist(TALLOC_CTX *mem_ctx, const DOM_SID *sids,
		   size_t num_sids, char **result, ssize_t *len)
{
	size_t i;
	size_t buflen = 0;

	*len = 0;
	*result = NULL;
	for (i=0; i<num_sids; i++) {
		fstring tmp;
		sprintf_append(mem_ctx, result, len, &buflen,
			       "%s\n", sid_to_fstring(tmp, &sids[i]));
	}

	if ((num_sids != 0) && (*result == NULL)) {
		return False;
	}

	return True;
}

bool parse_sidlist(TALLOC_CTX *mem_ctx, const char *sidstr,
		   DOM_SID **sids, size_t *num_sids)
{
	const char *p, *q;

	p = sidstr;
	if (p == NULL)
		return False;

	while (p[0] != '\0') {
		fstring tmp;
		size_t sidlen;
		DOM_SID sid;
		q = strchr(p, '\n');
		if (q == NULL) {
			DEBUG(0, ("Got invalid sidstr: %s\n", p));
			return False;
		}
		sidlen = PTR_DIFF(q, p);
		if (sidlen >= sizeof(tmp)-1) {
			return false;
		}
		memcpy(tmp, p, sidlen);
		tmp[sidlen] = '\0';
		q += 1;
		if (!string_to_sid(&sid, tmp)) {
			DEBUG(0, ("Could not parse sid %s\n", p));
			return False;
		}
		if (!NT_STATUS_IS_OK(add_sid_to_array(mem_ctx, &sid, sids,
						      num_sids)))
		{
			return False;
		}
		p = q;
	}
	return True;
}

static void getsidaliases_recv(TALLOC_CTX *mem_ctx, bool success,
			       struct winbindd_response *response,
			       void *c, void *private_data)
{
	void (*cont)(void *priv, bool succ,
		     DOM_SID *aliases, size_t num_aliases) =
		(void (*)(void *, bool, DOM_SID *, size_t))c;
	char *aliases_str;
	DOM_SID *sids = NULL;
	size_t num_sids = 0;

	if (!success) {
		DEBUG(5, ("Could not trigger getsidaliases\n"));
		cont(private_data, success, NULL, 0);
		return;
	}

	if (response->result != WINBINDD_OK) {
		DEBUG(5, ("getsidaliases returned an error\n"));
		cont(private_data, False, NULL, 0);
		return;
	}

	aliases_str = (char *)response->extra_data.data;

	if (aliases_str == NULL) {
		DEBUG(10, ("getsidaliases return 0 SIDs\n"));
		cont(private_data, True, NULL, 0);
		return;
	}

	if (!parse_sidlist(mem_ctx, aliases_str, &sids, &num_sids)) {
		DEBUG(0, ("Could not parse sids\n"));
		cont(private_data, False, NULL, 0);
		return;
	}

	cont(private_data, True, sids, num_sids);
}

void winbindd_getsidaliases_async(struct winbindd_domain *domain,
				  TALLOC_CTX *mem_ctx,
				  const DOM_SID *sids, size_t num_sids,
			 	  void (*cont)(void *private_data,
				 	       bool success,
					       const DOM_SID *aliases,
					       size_t num_aliases),
				  void *private_data)
{
	struct winbindd_request request;
	char *sidstr = NULL;
	ssize_t len;

	if (num_sids == 0) {
		cont(private_data, True, NULL, 0);
		return;
	}

	if (!print_sidlist(mem_ctx, sids, num_sids, &sidstr, &len)) {
		cont(private_data, False, NULL, 0);
		return;
	}

	ZERO_STRUCT(request);
	request.cmd = WINBINDD_DUAL_GETSIDALIASES;
	request.extra_len = len;
	request.extra_data.data = sidstr;

	do_async_domain(mem_ctx, domain, &request, getsidaliases_recv,
			(void *)cont, private_data);
}

static void query_user_recv(TALLOC_CTX *mem_ctx, bool success,
			    struct winbindd_response *response,
			    void *c, void *private_data)
{
	void (*cont)(void *priv, bool succ, const char *acct_name,
		     const char *full_name, const char *homedir, 
		     const char *shell, uint32 gid, uint32 group_rid) =
		(void (*)(void *, bool, const char *, const char *,
			  const char *, const char *, uint32, uint32))c;

	if (!success) {
		DEBUG(5, ("Could not trigger query_user\n"));
		cont(private_data, False, NULL, NULL, NULL, NULL, -1, -1);
		return;
	}

	if (response->result != WINBINDD_OK) {
                DEBUG(5, ("query_user returned an error\n"));
		cont(private_data, False, NULL, NULL, NULL, NULL, -1, -1);
		return;
	}

	cont(private_data, True, response->data.user_info.acct_name,
	     response->data.user_info.full_name,
	     response->data.user_info.homedir,
	     response->data.user_info.shell,
	     response->data.user_info.primary_gid,
	     response->data.user_info.group_rid);
}

void query_user_async(TALLOC_CTX *mem_ctx, struct winbindd_domain *domain,
		      const DOM_SID *sid,
		      void (*cont)(void *private_data, bool success,
				   const char *acct_name,
				   const char *full_name,
				   const char *homedir,
				   const char *shell,
				   gid_t gid,
				   uint32 group_rid),
		      void *private_data)
{
	struct winbindd_request request;
	ZERO_STRUCT(request);
	request.cmd = WINBINDD_DUAL_USERINFO;
	sid_to_fstring(request.data.sid, sid);
	do_async_domain(mem_ctx, domain, &request, query_user_recv,
			(void *)cont, private_data);
}

enum winbindd_result winbindd_dual_ping(struct winbindd_domain *domain,
					struct winbindd_cli_state *state)
{
	return WINBINDD_OK;
}