/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2009 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Daniel Beulshausen <daniel@php4win.de>                      |
   +----------------------------------------------------------------------+
*/

/* $Id$ */

#include <stdio.h>
#include <fcntl.h>
#include <io.h>
#include <process.h>
#include <time.h>
#include <errno.h>

#define TSRM_INCLUDE_FULL_WINDOWS_HEADERS
#include "SAPI.h"
#include "TSRM.h"

#ifdef TSRM_WIN32

#include "tsrm_win32.h"
#include "tsrm_virtual_cwd.h"

#ifdef ZTS
static ts_rsrc_id win32_globals_id;
#else
static tsrm_win32_globals win32_globals;
#endif

static void tsrm_win32_ctor(tsrm_win32_globals *globals TSRMLS_DC)
{
	HANDLE process_token = NULL;

	globals->process = NULL;
	globals->shm	 = NULL;
	globals->process_size = 0;
	globals->shm_size	  = 0;
	globals->comspec = _strdup((GetVersion()<0x80000000)?"cmd.exe":"command.com");
	globals->impersonation_token = NULL;

	/* Access check requires impersonation token. Create a duplicate token. */
	if(OpenProcessToken(GetCurrentProcess(), TOKEN_DUPLICATE | TOKEN_QUERY, &process_token)) {
		DuplicateToken(process_token, SecurityImpersonation, &globals->impersonation_token);
	}

	/* impersonation_token will be closed when the process dies */
	if(process_token != NULL) {
		CloseHandle(process_token);
		process_token = NULL;
	}
}

static void tsrm_win32_dtor(tsrm_win32_globals *globals TSRMLS_DC)
{
	shm_pair *ptr;

	if (globals->process) {
		free(globals->process);
	}

	if (globals->shm) {
		for (ptr = globals->shm; ptr < (globals->shm + globals->shm_size); ptr++) {
			UnmapViewOfFile(ptr->addr);
			CloseHandle(ptr->segment);
			UnmapViewOfFile(ptr->descriptor);
			CloseHandle(ptr->info);
		}
		free(globals->shm);
	}

	free(globals->comspec);

	if(globals->impersonation_token) {
		CloseHandle(globals->impersonation_token);
	}
}

TSRM_API void tsrm_win32_startup(void)
{
#ifdef ZTS
	ts_allocate_id(&win32_globals_id, sizeof(tsrm_win32_globals), (ts_allocate_ctor)tsrm_win32_ctor, (ts_allocate_ctor)tsrm_win32_dtor);
#else
	tsrm_win32_ctor(&win32_globals TSRMLS_CC);
#endif
}

TSRM_API void tsrm_win32_shutdown(void)
{
#ifndef ZTS
	tsrm_win32_dtor(&win32_globals TSRMLS_CC);
#endif
}

TSRM_API int tsrm_win32_access(const char *pathname, int mode)
{
	SECURITY_INFORMATION sec_info = OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION;
	GENERIC_MAPPING gen_map = { FILE_GENERIC_READ, FILE_GENERIC_WRITE, FILE_GENERIC_EXECUTE, FILE_ALL_ACCESS };
	DWORD priv_set_length = sizeof(PRIVILEGE_SET);

	PRIVILEGE_SET privilege_set = {0};
	DWORD sec_desc_length = 0, desired_access = 0, granted_access = 0;
	BYTE * psec_desc = NULL;
	BOOL fAccess = FALSE;
	HANDLE process_token = NULL;

	realpath_cache_bucket * bucket = NULL;
	char * real_path = NULL;
	time_t t;

	TSRMLS_FETCH();

	if (mode == 1 /*X_OK*/) {
		DWORD type;
		return GetBinaryType(pathname, &type) ? 0 : -1;
	} else {
		if(access(pathname, mode)) {
			return errno;
		}

		if(!IS_ABSOLUTE_PATH(pathname, strlen(pathname)+1)) {
			real_path = (char *)malloc(MAX_PATH);
			if(tsrm_realpath(pathname, real_path TSRMLS_CC) == NULL) {
				goto Finished;
			}
			pathname = real_path;
 		}

		if (CWDG(realpath_cache_size_limit)) {
			t = time(0);
			bucket = realpath_cache_lookup(pathname, strlen(pathname), t TSRMLS_CC);
			if(bucket == NULL && real_path == NULL) {
				/* We used the pathname directly. Call tsrm_realpath */
				/* so that entry is created in realpath cache */
				real_path = (char *)malloc(MAX_PATH);
				if(tsrm_realpath(pathname, real_path TSRMLS_CC) != NULL) {
					pathname = real_path;
					bucket = realpath_cache_lookup(pathname, strlen(pathname), t TSRMLS_CC);
				}
			}
 		}
 
 		/* Do a full access check because access() will only check read-only attribute */
 		if(mode == 0 || mode > 6) {
			if(bucket != NULL && bucket->is_rvalid) {
				fAccess = bucket->is_readable;
				goto Finished;
			}
 			desired_access = FILE_GENERIC_READ;
 		} else if(mode <= 2) {
			if(bucket != NULL && bucket->is_wvalid) {
				fAccess = bucket->is_writable;
				goto Finished;
			}
			desired_access = FILE_GENERIC_WRITE;
 		} else if(mode <= 4) {
			if(bucket != NULL && bucket->is_rvalid) {
				fAccess = bucket->is_readable;
				goto Finished;
			}
			desired_access = FILE_GENERIC_READ|FILE_FLAG_BACKUP_SEMANTICS;
 		} else { // if(mode <= 6)
			if(bucket != NULL && bucket->is_rvalid && bucket->is_wvalid) {
				fAccess = bucket->is_readable & bucket->is_writable;
				goto Finished;
			}
			desired_access = FILE_GENERIC_READ | FILE_GENERIC_WRITE;
 		}

		if(TWG(impersonation_token) == NULL) {
			goto Finished;
		}

		/* Get size of security buffer. Call is expected to fail */
		if(GetFileSecurity(pathname, sec_info, NULL, 0, &sec_desc_length)) {
			goto Finished;
		}

		psec_desc = (BYTE *)malloc(sec_desc_length);
		if(psec_desc == NULL ||
			 !GetFileSecurity(pathname, sec_info, (PSECURITY_DESCRIPTOR)psec_desc, sec_desc_length, &sec_desc_length)) {
			goto Finished;
		}

		if(!AccessCheck((PSECURITY_DESCRIPTOR)psec_desc, TWG(impersonation_token), desired_access, &gen_map, &privilege_set, &priv_set_length, &granted_access, &fAccess)) {
				goto Finished;
		}

		/* Keep the result in realpath_cache */
		if(bucket != NULL) {
			if(desired_access == (FILE_GENERIC_READ|FILE_FLAG_BACKUP_SEMANTICS)) {
				bucket->is_rvalid = 1;
				bucket->is_readable = fAccess;
			}
			else if(desired_access == FILE_GENERIC_WRITE) {
				bucket->is_wvalid = 1;
				bucket->is_writable = fAccess;
			}
		}

Finished:
		if(psec_desc != NULL) {
			free(psec_desc);
			psec_desc = NULL;
		}

		if(real_path != NULL) {
			free(real_path);
			real_path = NULL;
		}

		if(fAccess == FALSE) {
			errno = EACCES;
			return errno;
		} else {
			return 0;
		}
	}
}


static process_pair *process_get(FILE *stream TSRMLS_DC)
{
	process_pair *ptr;
	process_pair *newptr;

	for (ptr = TWG(process); ptr < (TWG(process) + TWG(process_size)); ptr++) {
		if (ptr->stream == stream) {
			break;
		}
	}

	if (ptr < (TWG(process) + TWG(process_size))) {
		return ptr;
	}

	newptr = (process_pair*)realloc((void*)TWG(process), (TWG(process_size)+1)*sizeof(process_pair));
	if (newptr == NULL) {
		return NULL;
	}

	TWG(process) = newptr;
	ptr = newptr + TWG(process_size);
	TWG(process_size)++;
	return ptr;
}

static shm_pair *shm_get(int key, void *addr)
{
	shm_pair *ptr;
	shm_pair *newptr;
	TSRMLS_FETCH();

	for (ptr = TWG(shm); ptr < (TWG(shm) + TWG(shm_size)); ptr++) {
		if (!ptr->descriptor) {
			continue;
		}
		if (!addr && ptr->descriptor->shm_perm.key == key) {
			break;
		} else if (ptr->addr == addr) {
			break;
		}
	}

	if (ptr < (TWG(shm) + TWG(shm_size))) {
		return ptr;
	}

	newptr = (shm_pair*)realloc((void*)TWG(shm), (TWG(shm_size)+1)*sizeof(shm_pair));
	if (newptr == NULL) {
		return NULL;
	}

	TWG(shm) = newptr;
	ptr = newptr + TWG(shm_size);
	TWG(shm_size)++;
	return ptr;
}

static HANDLE dupHandle(HANDLE fh, BOOL inherit) {
	HANDLE copy, self = GetCurrentProcess();
	if (!DuplicateHandle(self, fh, self, &copy, 0, inherit, DUPLICATE_SAME_ACCESS|DUPLICATE_CLOSE_SOURCE)) {
		return NULL;
	}
	return copy;
}

TSRM_API FILE *popen(const char *command, const char *type)
{
	return popen_ex(command, type, NULL, NULL);
}

TSRM_API FILE *popen_ex(const char *command, const char *type, const char *cwd, char *env)
{
	FILE *stream = NULL;
	int fno, type_len = strlen(type), read, mode;
	STARTUPINFO startup;
	PROCESS_INFORMATION process;
	SECURITY_ATTRIBUTES security;
	HANDLE in, out;
	DWORD dwCreateFlags = 0;
	BOOL res;
	process_pair *proc;
	char *cmd;
	int i;
	char *ptype = (char *)type;
	HANDLE thread_token = NULL;
	HANDLE token_user = NULL;
	BOOL asuser = TRUE;

	TSRMLS_FETCH();

	if (!type) {
		return NULL;
	}

	/*The following two checks can be removed once we drop XP support */
	type_len = strlen(type);
	if (type_len <1 || type_len > 2) {
		return NULL;
	}

	for (i=0; i < type_len; i++) {
		if (!(*ptype == 'r' || *ptype == 'w' || *ptype == 'b' || *ptype == 't')) {
			return NULL;
		}
		ptype++;
	}

	security.nLength				= sizeof(SECURITY_ATTRIBUTES);
	security.bInheritHandle			= TRUE;
	security.lpSecurityDescriptor	= NULL;

	if (!type_len || !CreatePipe(&in, &out, &security, 2048L)) {
		return NULL;
	}

	memset(&startup, 0, sizeof(STARTUPINFO));
	memset(&process, 0, sizeof(PROCESS_INFORMATION));

	startup.cb			= sizeof(STARTUPINFO);
	startup.dwFlags		= STARTF_USESTDHANDLES;
	startup.hStdError	= GetStdHandle(STD_ERROR_HANDLE);

	read = (type[0] == 'r') ? TRUE : FALSE;
	mode = ((type_len == 2) && (type[1] == 'b')) ? O_BINARY : O_TEXT;

	if (read) {
		in = dupHandle(in, FALSE);
		startup.hStdInput  = GetStdHandle(STD_INPUT_HANDLE);
		startup.hStdOutput = out;
	} else {
		out = dupHandle(out, FALSE);
		startup.hStdInput  = in;
		startup.hStdOutput = GetStdHandle(STD_OUTPUT_HANDLE);
	}

	dwCreateFlags = NORMAL_PRIORITY_CLASS;
	if (strcmp(sapi_module.name, "cli") != 0) {
		dwCreateFlags |= CREATE_NO_WINDOW;
	}

	/* Get a token with the impersonated user. */
	if(OpenThreadToken(GetCurrentThread(), TOKEN_ALL_ACCESS, TRUE, &thread_token)) {
		DuplicateTokenEx(thread_token, MAXIMUM_ALLOWED, &security, SecurityImpersonation, TokenPrimary, &token_user);
	} else {
		DWORD err = GetLastError();
		if (err == ERROR_NO_TOKEN) {
			asuser = FALSE;
		}
	}

	cmd = (char*)malloc(strlen(command)+strlen(TWG(comspec))+sizeof(" /c ")+2);
	sprintf(cmd, "%s /c \"%s\"", TWG(comspec), command);
	if (asuser) {
		res = CreateProcessAsUser(token_user, NULL, cmd, &security, &security, security.bInheritHandle, dwCreateFlags, env, cwd, &startup, &process);
		CloseHandle(token_user);
	} else {
		res = CreateProcess(NULL, cmd, &security, &security, security.bInheritHandle, dwCreateFlags, env, cwd, &startup, &process);
	}
	free(cmd);

	if (!res) {
		return NULL;
	}

	CloseHandle(process.hThread);
	proc = process_get(NULL TSRMLS_CC);

	if (read) {
		fno = _open_osfhandle((tsrm_intptr_t)in, _O_RDONLY | mode);
		CloseHandle(out);
	} else {
		fno = _open_osfhandle((tsrm_intptr_t)out, _O_WRONLY | mode);
		CloseHandle(in);
	}

	stream = _fdopen(fno, type);
	proc->prochnd = process.hProcess;
	proc->stream = stream;
	return stream;
}

TSRM_API int pclose(FILE *stream)
{
	DWORD termstat = 0;
	process_pair *process;
	TSRMLS_FETCH();

	if ((process = process_get(stream TSRMLS_CC)) == NULL) {
		return 0;
	}

	fflush(process->stream);
	fclose(process->stream);

	WaitForSingleObject(process->prochnd, INFINITE);
	GetExitCodeProcess(process->prochnd, &termstat);
	process->stream = NULL;
	CloseHandle(process->prochnd);

	return termstat;
}

TSRM_API int shmget(int key, int size, int flags)
{
	shm_pair *shm;
	char shm_segment[26], shm_info[29];
	HANDLE shm_handle, info_handle;
	BOOL created = FALSE;

	if (size < 0) {
		return -1;
	}

	sprintf(shm_segment, "TSRM_SHM_SEGMENT:%d", key);
	sprintf(shm_info, "TSRM_SHM_DESCRIPTOR:%d", key);

	shm_handle  = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, shm_segment);
	info_handle = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, shm_info);

	if ((!shm_handle && !info_handle)) {
		if (flags & IPC_CREAT) {
			shm_handle	= CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, size, shm_segment);
			info_handle	= CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, sizeof(shm->descriptor), shm_info);
			created		= TRUE;
		}
		if ((!shm_handle || !info_handle)) {
			return -1;
		}
	} else {
		if (flags & IPC_EXCL) {
			return -1;
		}
	}

	shm = shm_get(key, NULL);
	shm->segment = shm_handle;
	shm->info	 = info_handle;
	shm->descriptor = MapViewOfFileEx(shm->info, FILE_MAP_ALL_ACCESS, 0, 0, 0, NULL);

	if (created) {
		shm->descriptor->shm_perm.key	= key;
		shm->descriptor->shm_segsz		= size;
		shm->descriptor->shm_ctime		= time(NULL);
		shm->descriptor->shm_cpid		= getpid();
		shm->descriptor->shm_perm.mode	= flags;

		shm->descriptor->shm_perm.cuid	= shm->descriptor->shm_perm.cgid= 0;
		shm->descriptor->shm_perm.gid	= shm->descriptor->shm_perm.uid = 0;
		shm->descriptor->shm_atime		= shm->descriptor->shm_dtime	= 0;
		shm->descriptor->shm_lpid		= shm->descriptor->shm_nattch	= 0;
		shm->descriptor->shm_perm.mode	= shm->descriptor->shm_perm.seq	= 0;
	}

	if (shm->descriptor->shm_perm.key != key || size > shm->descriptor->shm_segsz ) {
		CloseHandle(shm->segment);
		UnmapViewOfFile(shm->descriptor);
		CloseHandle(shm->info);
		return -1;
	}

	return key;
}

TSRM_API void *shmat(int key, const void *shmaddr, int flags)
{
	shm_pair *shm = shm_get(key, NULL);

	if (!shm->segment) {
		return (void*)-1;
	}

	shm->descriptor->shm_atime = time(NULL);
	shm->descriptor->shm_lpid  = getpid();
	shm->descriptor->shm_nattch++;

	shm->addr = MapViewOfFileEx(shm->segment, FILE_MAP_ALL_ACCESS, 0, 0, 0, NULL);

	return shm->addr;
}

TSRM_API int shmdt(const void *shmaddr)
{
	shm_pair *shm = shm_get(0, (void*)shmaddr);

	if (!shm->segment) {
		return -1;
	}

	shm->descriptor->shm_dtime = time(NULL);
	shm->descriptor->shm_lpid  = getpid();
	shm->descriptor->shm_nattch--;

	return UnmapViewOfFile(shm->addr) ? 0 : -1;
}

TSRM_API int shmctl(int key, int cmd, struct shmid_ds *buf) {
	shm_pair *shm = shm_get(key, NULL);

	if (!shm->segment) {
		return -1;
	}

	switch (cmd) {
		case IPC_STAT:
			memcpy(buf, shm->descriptor, sizeof(struct shmid_ds));
			return 0;

		case IPC_SET:
			shm->descriptor->shm_ctime		= time(NULL);
			shm->descriptor->shm_perm.uid	= buf->shm_perm.uid;
			shm->descriptor->shm_perm.gid	= buf->shm_perm.gid;
			shm->descriptor->shm_perm.mode	= buf->shm_perm.mode;
			return 0;

		case IPC_RMID:
			if (shm->descriptor->shm_nattch < 1) {
				shm->descriptor->shm_perm.key = -1;
			}
			return 0;

		default:
			return -1;
	}
}

TSRM_API char *realpath(char *orig_path, char *buffer)
{
	int ret = GetFullPathName(orig_path, _MAX_PATH, buffer, NULL);
	if(!ret || ret > _MAX_PATH) {
		return NULL;
	}
	return buffer;
}

#endif