/* 
   Unix SMB/CIFS implementation.
   Authentication utility functions
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Andrew Bartlett 2001
   Copyright (C) Jeremy Allison 2000-2001
   Copyright (C) Rafal Szczesniak 2002
   Copyright (C) Stefan Metzmacher 2005

   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 "auth/auth.h"
#include "libcli/auth/libcli_auth.h"
#include "param/param.h"
#include "auth/ntlm/auth_proto.h"
#include "librpc/gen_ndr/drsuapi.h"
#include "dsdb/samdb/samdb.h"

/* this default function can be used by mostly all backends
 * which don't want to set a challenge
 */
NTSTATUS auth_get_challenge_not_implemented(struct auth_method_context *ctx, TALLOC_CTX *mem_ctx, uint8_t chal[8])
{
	/* we don't want to set a challenge */
	return NT_STATUS_NOT_IMPLEMENTED;
}

/****************************************************************************
 Create an auth_usersupplied_data structure after appropriate mapping.
****************************************************************************/
static NTSTATUS map_user_info_cracknames(struct ldb_context *sam_ctx,
					 TALLOC_CTX *mem_ctx,
					 const char *default_domain,
					 const struct auth_usersupplied_info *user_info,
					 struct auth_usersupplied_info **user_info_mapped)
{
	char *domain;
	char *account_name;
	TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
	WERROR werr;
	struct drsuapi_DsNameInfo1 info1;

	DEBUG(5,("map_user_info_cracknames: Mapping user [%s]\\[%s] from workstation [%s]\n",
		 user_info->client.domain_name, user_info->client.account_name, user_info->workstation_name));

	account_name = talloc_strdup(tmp_ctx, user_info->client.account_name);
	if (!account_name) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}

	/* use cracknames to work out what domain is being
	   asked for */
	if (strchr_m(user_info->client.account_name, '@') != NULL) {
		werr = DsCrackNameOneName(sam_ctx, tmp_ctx, 0,
					  DRSUAPI_DS_NAME_FORMAT_USER_PRINCIPAL,
					  DRSUAPI_DS_NAME_FORMAT_NT4_ACCOUNT,
					  user_info->client.account_name,
					  &info1);
		if (!W_ERROR_IS_OK(werr)) {
			DEBUG(2,("map_user_info: Failed cracknames of account '%s'\n",
				 user_info->client.account_name));
			talloc_free(tmp_ctx);
			return werror_to_ntstatus(werr);
		}
		switch (info1.status) {
		case DRSUAPI_DS_NAME_STATUS_OK:
			break;
		case DRSUAPI_DS_NAME_STATUS_NOT_FOUND:
			DEBUG(2,("map_user_info: Cracknames of account '%s' -> NOT_FOUND\n",
				 user_info->client.account_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		case DRSUAPI_DS_NAME_STATUS_DOMAIN_ONLY:
			DEBUG(2,("map_user_info: Cracknames of account '%s' -> DOMAIN_ONLY\n",
				 user_info->client.account_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		case DRSUAPI_DS_NAME_STATUS_NOT_UNIQUE:
			DEBUG(2,("map_user_info: Cracknames of account '%s' -> NOT_UNIQUE\n",
				 user_info->client.account_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		case DRSUAPI_DS_NAME_STATUS_RESOLVE_ERROR:
			DEBUG(2,("map_user_info: Cracknames of account '%s' -> RESOLVE_ERROR\n",
				 user_info->client.account_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		default:
			DEBUG(2,("map_user_info: Cracknames of account '%s' -> unknown error %u\n",
				 user_info->client.account_name, info1.status));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		}
		/* info1.result_name is in DOMAIN\username
		 * form, which we need to split up into the
		 * user_info_mapped structure
		 */
		domain = talloc_strdup(tmp_ctx, info1.result_name);
		if (domain == NULL) {
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_MEMORY;
		}
		account_name = strchr_m(domain, '\\');
		if (account_name == NULL) {
			DEBUG(2,("map_user_info: Cracknames of account '%s' gave invalid result '%s'\n",
				 user_info->client.account_name, info1.result_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		}
		*account_name = 0;
		account_name = talloc_strdup(tmp_ctx, account_name+1);
		if (account_name == NULL) {
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_MEMORY;
		}
	} else {
		char *domain_name;
		if (user_info->client.domain_name && *user_info->client.domain_name) {
			domain_name = talloc_asprintf(tmp_ctx, "%s\\", user_info->client.domain_name);
		} else {
			domain_name = talloc_strdup(tmp_ctx, default_domain);
		}
		if (domain_name == NULL) {
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_MEMORY;
		}
		werr = DsCrackNameOneName(sam_ctx, mem_ctx, 0,
					  DRSUAPI_DS_NAME_FORMAT_NT4_ACCOUNT,
					  DRSUAPI_DS_NAME_FORMAT_NT4_ACCOUNT,
					  domain_name,
					  &info1);
		if (!W_ERROR_IS_OK(werr)) {
			DEBUG(2,("map_user_info: Failed cracknames of domain '%s'\n",
				 domain_name));
			talloc_free(tmp_ctx);
			return werror_to_ntstatus(werr);
		}

		/* we use the account_name as-is, but get the
		 * domain name from cracknames if possible */
		account_name = talloc_strdup(mem_ctx, user_info->client.account_name);
		if (account_name == NULL) {
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_MEMORY;
		}

		switch (info1.status) {
		case DRSUAPI_DS_NAME_STATUS_OK:
		case DRSUAPI_DS_NAME_STATUS_DOMAIN_ONLY:
			domain = talloc_strdup(tmp_ctx, info1.result_name);
			if (domain == NULL) {
				talloc_free(tmp_ctx);
				return NT_STATUS_NO_MEMORY;
			}
			if (domain[strlen_m(domain)-1] == '\\') {
				domain[strlen_m(domain)-1] = 0;
			}
			break;
		case DRSUAPI_DS_NAME_STATUS_NOT_FOUND:
			/* the domain is unknown - use the
			   default domain */
			domain = talloc_strdup(tmp_ctx, default_domain);
			break;
		case DRSUAPI_DS_NAME_STATUS_NOT_UNIQUE:
			DEBUG(2,("map_user_info: Cracknames of domain '%s' -> NOT_UNIQUE\n",
				 domain_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		case DRSUAPI_DS_NAME_STATUS_RESOLVE_ERROR:
			DEBUG(2,("map_user_info: Cracknames of domain '%s' -> RESOLVE_ERROR\n",
				 domain_name));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		default:
			DEBUG(2,("map_user_info: Cracknames of account '%s' -> unknown error %u\n",
				 domain_name, info1.status));
			talloc_free(tmp_ctx);
			return NT_STATUS_NO_SUCH_USER;
		}
		/* domain and account_name are filled in above */
	}

	*user_info_mapped = talloc_zero(mem_ctx, struct auth_usersupplied_info);
	if (!*user_info_mapped) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}
	if (!talloc_reference(*user_info_mapped, user_info)) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}
	**user_info_mapped = *user_info;
	(*user_info_mapped)->mapped_state = true;
	(*user_info_mapped)->mapped.domain_name = talloc_strdup(*user_info_mapped, domain);
	(*user_info_mapped)->mapped.account_name = talloc_strdup(*user_info_mapped, account_name);
	talloc_free(tmp_ctx);
	if (!(*user_info_mapped)->mapped.domain_name
	    || !(*user_info_mapped)->mapped.account_name) {
		return NT_STATUS_NO_MEMORY;
	}

	return NT_STATUS_OK;
}


/****************************************************************************
 Create an auth_usersupplied_data structure after appropriate mapping.
****************************************************************************/
NTSTATUS map_user_info(struct ldb_context *sam_ctx,
		       TALLOC_CTX *mem_ctx,
		       const char *default_domain,
		       const struct auth_usersupplied_info *user_info,
		       struct auth_usersupplied_info **user_info_mapped)
{
	char *domain;
	char *account_name;
	char *d;
	TALLOC_CTX *tmp_ctx;

	if (sam_ctx != NULL) {
		/* if possible, use cracknames to parse the
		   domain/account */
		return map_user_info_cracknames(sam_ctx, mem_ctx, default_domain, user_info, user_info_mapped);
	}

	DEBUG(0,("map_user_info: Mapping user [%s]\\[%s] from workstation [%s] default_domain=%s\n",
		 user_info->client.domain_name, user_info->client.account_name, user_info->workstation_name,
		 default_domain));

	tmp_ctx = talloc_new(mem_ctx);

	account_name = talloc_strdup(tmp_ctx, user_info->client.account_name);
	if (!account_name) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}
	
	/* don't allow "" as a domain, fixes a Win9X bug where it
	   doesn't supply a domain for logon script 'net use'
	   commands.  */

	/* Split user@realm names into user and realm components.
	 * This is TODO to fix with proper userprincipalname
	 * support */
	if (user_info->client.domain_name && *user_info->client.domain_name) {
		domain = talloc_strdup(tmp_ctx, user_info->client.domain_name);
	} else if (strchr_m(user_info->client.account_name, '@')) {
		d = strchr_m(account_name, '@');
		if (!d) {
			talloc_free(tmp_ctx);
			return NT_STATUS_INTERNAL_ERROR;
		}
		d[0] = '\0';
		d++;
		domain = d;
	} else {
		domain = talloc_strdup(tmp_ctx, default_domain);
	}

	if (domain == NULL) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}
	*user_info_mapped = talloc_zero(mem_ctx, struct auth_usersupplied_info);
	if (!*user_info_mapped) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}
	if (!talloc_reference(*user_info_mapped, user_info)) {
		talloc_free(tmp_ctx);
		return NT_STATUS_NO_MEMORY;
	}
	**user_info_mapped = *user_info;
	(*user_info_mapped)->mapped_state = true;
	(*user_info_mapped)->mapped.domain_name = talloc_strdup(*user_info_mapped, domain);
	(*user_info_mapped)->mapped.account_name = talloc_strdup(*user_info_mapped, account_name);
	talloc_free(tmp_ctx);
	if (!(*user_info_mapped)->mapped.domain_name 
	    || !(*user_info_mapped)->mapped.account_name) {
		return NT_STATUS_NO_MEMORY;
	}

	return NT_STATUS_OK;
}

/****************************************************************************
 Create an auth_usersupplied_data structure after appropriate mapping.
****************************************************************************/

NTSTATUS encrypt_user_info(TALLOC_CTX *mem_ctx, struct auth4_context *auth_context, 
			   enum auth_password_state to_state,
			   const struct auth_usersupplied_info *user_info_in,
			   const struct auth_usersupplied_info **user_info_encrypted)
{
	NTSTATUS nt_status;
	struct auth_usersupplied_info *user_info_temp;
	switch (to_state) {
	case AUTH_PASSWORD_RESPONSE:
		switch (user_info_in->password_state) {
		case AUTH_PASSWORD_PLAIN:
		{
			const struct auth_usersupplied_info *user_info_temp2;
			nt_status = encrypt_user_info(mem_ctx, auth_context, 
						      AUTH_PASSWORD_HASH, 
						      user_info_in, &user_info_temp2);
			if (!NT_STATUS_IS_OK(nt_status)) {
				return nt_status;
			}
			user_info_in = user_info_temp2;
			/* fall through */
		}
		case AUTH_PASSWORD_HASH:
		{
			uint8_t chal[8];
			DATA_BLOB chall_blob;
			user_info_temp = talloc_zero(mem_ctx, struct auth_usersupplied_info);
			if (!user_info_temp) {
				return NT_STATUS_NO_MEMORY;
			}
			if (!talloc_reference(user_info_temp, user_info_in)) {
				return NT_STATUS_NO_MEMORY;
			}
			*user_info_temp = *user_info_in;
			user_info_temp->mapped_state = to_state;
			
			nt_status = auth_get_challenge(auth_context, chal);
			if (!NT_STATUS_IS_OK(nt_status)) {
				return nt_status;
			}
			
			chall_blob = data_blob_talloc(mem_ctx, chal, 8);
			if (lpcfg_client_ntlmv2_auth(auth_context->lp_ctx)) {
				DATA_BLOB names_blob = NTLMv2_generate_names_blob(mem_ctx,  lpcfg_netbios_name(auth_context->lp_ctx), lpcfg_workgroup(auth_context->lp_ctx));
				DATA_BLOB lmv2_response, ntlmv2_response, lmv2_session_key, ntlmv2_session_key;
				
				if (!SMBNTLMv2encrypt_hash(user_info_temp,
							   user_info_in->client.account_name, 
							   user_info_in->client.domain_name, 
							   user_info_in->password.hash.nt->hash,
							   &chall_blob,
							   NULL, /* server_timestamp */
							   &names_blob,
							   &lmv2_response, &ntlmv2_response, 
							   &lmv2_session_key, &ntlmv2_session_key)) {
					data_blob_free(&names_blob);
					return NT_STATUS_NO_MEMORY;
				}
				data_blob_free(&names_blob);
				user_info_temp->password.response.lanman = lmv2_response;
				user_info_temp->password.response.nt = ntlmv2_response;
				
				data_blob_free(&lmv2_session_key);
				data_blob_free(&ntlmv2_session_key);
			} else {
				DATA_BLOB blob = data_blob_talloc(mem_ctx, NULL, 24);
				SMBOWFencrypt(user_info_in->password.hash.nt->hash, chal, blob.data);

				user_info_temp->password.response.nt = blob;
				if (lpcfg_client_lanman_auth(auth_context->lp_ctx) && user_info_in->password.hash.lanman) {
					DATA_BLOB lm_blob = data_blob_talloc(mem_ctx, NULL, 24);
					SMBOWFencrypt(user_info_in->password.hash.lanman->hash, chal, blob.data);
					user_info_temp->password.response.lanman = lm_blob;
				} else {
					/* if not sending the LM password, send the NT password twice */
					user_info_temp->password.response.lanman = user_info_temp->password.response.nt;
				}
			}

			user_info_in = user_info_temp;
			/* fall through */
		}
		case AUTH_PASSWORD_RESPONSE:
			*user_info_encrypted = user_info_in;
		}
		break;
	case AUTH_PASSWORD_HASH:
	{	
		switch (user_info_in->password_state) {
		case AUTH_PASSWORD_PLAIN:
		{
			struct samr_Password lanman;
			struct samr_Password nt;
			
			user_info_temp = talloc_zero(mem_ctx, struct auth_usersupplied_info);
			if (!user_info_temp) {
				return NT_STATUS_NO_MEMORY;
			}
			if (!talloc_reference(user_info_temp, user_info_in)) {
				return NT_STATUS_NO_MEMORY;
			}
			*user_info_temp = *user_info_in;
			user_info_temp->mapped_state = to_state;
			
			if (E_deshash(user_info_in->password.plaintext, lanman.hash)) {
				user_info_temp->password.hash.lanman = talloc(user_info_temp,
									      struct samr_Password);
				*user_info_temp->password.hash.lanman = lanman;
			} else {
				user_info_temp->password.hash.lanman = NULL;
			}
			
			E_md4hash(user_info_in->password.plaintext, nt.hash);
			user_info_temp->password.hash.nt = talloc(user_info_temp,
								   struct samr_Password);
			*user_info_temp->password.hash.nt = nt;
			
			user_info_in = user_info_temp;
			/* fall through */
		}
		case AUTH_PASSWORD_HASH:
			*user_info_encrypted = user_info_in;
			break;
		default:
			return NT_STATUS_INVALID_PARAMETER;
			break;
		}
		break;
	}
	default:
		return NT_STATUS_INVALID_PARAMETER;
	}

	return NT_STATUS_OK;
}
