/*

 * Copyright 2012--2014 Red Hat Inc., Durham, North Carolina.

 * All Rights Reserved.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 *

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <string.h>

#include <errno.h>

#ifdef OS_WINDOWS

#include <io.h>

#include <direct.h>

/* The rand_s function requires constant _CRT_RAND_S to be defined before including <stdlib.h>.

 * See https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/rand-s

 */

#define _CRT_RAND_S

#else

#include <unistd.h>

#include <ftw.h>

#endif

#include <stdlib.h>

#include <limits.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <curl/curl.h>

#include <curl/easy.h>

#include "oscap_acquire.h"

#include "common/util.h"

#include "common/oscap_buffer.h"

#include "common/_error.h"

#include "oscap_string.h"

#include "oscap_helpers.h"

#include "debug_priv.h"

#ifndef OSCAP_TEMP_DIR

#define OSCAP_TEMP_DIR "/tmp"

#endif

#define TEMP_DIR_TEMPLATE OSCAP_TEMP_DIR "/oscap.XXXXXX"

#define TEMP_URL_TEMPLATE "downloaded.XXXXXX"

#ifdef OS_WINDOWS

char *oscap_acquire_temp_dir()

{

	WCHAR temp_path[PATH_MAX];

	WCHAR temp_dir[PATH_MAX];

	DWORD ret = GetTempPathW(PATH_MAX, temp_path);

	if (ret > PATH_MAX || ret == 0) {

		oscap_seterr(OSCAP_EFAMILY_WINDOWS, "Could not retrieve the path of the directory for temporary files.");

		return NULL;

	}

	unsigned int unique;

	rand_s(&unique);

	ret = GetTempFileNameW(temp_path, L"oscap", unique, temp_dir);

	if (ret == 0) {

		oscap_seterr(OSCAP_EFAMILY_WINDOWS, "Could not get a name for new temporary directory.");

		return NULL;

	}

	char *temp_dir_str = oscap_windows_wstr_to_str(temp_dir);

	WCHAR *path_prefix = temp_dir;

	do {

		/* Use wide characters with L modifier because we work with a wide string. */

		WCHAR *delimiter = wcschr(path_prefix, L'\\');

		if (delimiter == NULL) {

			break;

		}

		*delimiter = L'\0';

		if (!CreateDirectoryW(temp_dir, NULL)) {

			ret = GetLastError();

			if (ret != ERROR_ALREADY_EXISTS) {

				char *error_message = oscap_windows_error_message(ret);

				oscap_seterr(OSCAP_EFAMILY_WINDOWS, "Could not create temp directory '%s': %s.", temp_dir_str, error_message);

				free(error_message);

				free(temp_dir_str);

				return NULL;

			}

		}

		*delimiter = L'\\';

		path_prefix = ++delimiter;

	} while (*path_prefix != L'\0');

	if (!CreateDirectoryW(temp_dir, NULL)) {

		ret = GetLastError();

		char *error_message = oscap_windows_error_message(ret);

		oscap_seterr(OSCAP_EFAMILY_WINDOWS, "Could not create temp directory '%s': %s.", temp_dir_str, error_message);

		free(error_message);

		free(temp_dir_str);

		return NULL;

	}

	return temp_dir_str;

}

#else

char *oscap_acquire_temp_dir()

{

	char *temp_dir = oscap_strdup(TEMP_DIR_TEMPLATE);

	if (mkdtemp(temp_dir) == NULL) {

		free(temp_dir);

		oscap_seterr(OSCAP_EFAMILY_GLIBC, "Could not create temp directory " TEMP_DIR_TEMPLATE ". %s", strerror(errno));

		return NULL;

	}

	return temp_dir;

}

#endif

#ifdef OS_WINDOWS

static bool _recursive_delete_directory(WCHAR *directory)

{

	if (directory == NULL) {

		return false;

	}

	WCHAR find_pattern[MAX_PATH];

	wcsncpy(find_pattern, directory, MAX_PATH);

	wcsncat(find_pattern, L"\\*", MAX_PATH);

	WCHAR dir_path[MAX_PATH];

	wcsncpy(dir_path, directory, MAX_PATH);

	wcsncat(dir_path, L"\\", MAX_PATH);

	WCHAR file_path[MAX_PATH];

	wcsncpy(file_path, dir_path, MAX_PATH);

	DWORD err;

	WIN32_FIND_DATAW find_data;

	HANDLE find_handle = FindFirstFileW(find_pattern, &find_data);

	if (find_handle == INVALID_HANDLE_VALUE) {

		err = GetLastError();

		char *error_message = oscap_windows_error_message(err);

		oscap_seterr(OSCAP_EFAMILY_WINDOWS, "FindFirstFileW error: %s", error_message);

		free(error_message);

		return false;

	}

	do {

		if (wcscmp(find_data.cFileName, L".") != 0 && wcscmp(find_data.cFileName, L"..") != 0) {

			wcsncat(file_path, find_data.cFileName, MAX_PATH);

			if (find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {

				if (!_recursive_delete_directory(file_path)) {

					FindClose(find_handle);

					return false;

				}

			} else {

				if (!DeleteFileW(file_path)) {

					err = GetLastError();

					char *error_message = oscap_windows_error_message(err);

					oscap_seterr(OSCAP_EFAMILY_WINDOWS, "DeleteFileW Error: %s", error_message);

					free(error_message);

					FindClose(find_handle);

					return false;

				}

			}

			wcsncpy(file_path, dir_path, MAX_PATH);

		}

	} while (FindNextFileW(find_handle, &find_data) != 0);

	FindClose(find_handle);

	if (!RemoveDirectoryW(dir_path)) {

		err = GetLastError();

		char *error_message = oscap_windows_error_message(err);

		oscap_seterr(OSCAP_EFAMILY_WINDOWS, "RemoveDirectoryW error: %s", error_message);

		free(error_message);

		return false;

	}

	return true;

}

void oscap_acquire_cleanup_dir(char **dir_path)

{

	if (*dir_path != NULL) {

		WCHAR *dir_path_wstr = oscap_windows_str_to_wstr(*dir_path);

		_recursive_delete_directory(dir_path_wstr);

		free(dir_path_wstr);

		free(*dir_path);

		*dir_path = NULL;

	}

}

#else

static int __unlink_cb(const char *fpath, const struct stat *sb, int typeflag, struct FTW *ftwbuf)

{

	int rv = remove(fpath);

	if (rv)

		oscap_seterr(OSCAP_EFAMILY_GLIBC, "Could not remove %s. %s", fpath, strerror(errno));

	return rv;

}

void oscap_acquire_cleanup_dir(char **dir_path)

{

	if (*dir_path != NULL)

	{

		nftw(*dir_path, __unlink_cb, 64, FTW_DEPTH | FTW_PHYS | FTW_MOUNT);

		free(*dir_path);

		*dir_path = NULL;

	}

}

#endif

int

oscap_acquire_temp_file(const char *dir, const char *template, char **filename)

{

#ifdef OS_WINDOWS

	int old_mode;

#else

	mode_t old_mode;

#endif

	int fd;

	if (dir == NULL || template == NULL || filename == NULL)

		return -1;

	*filename = malloc(PATH_MAX * sizeof(char));

	old_mode = umask(077); /* Override unusual umask. Ensure 0700 permissions. */

#ifdef OS_WINDOWS

	char *base_name = oscap_strdup(template);

	_mktemp_s(base_name, strlen(base_name) + 1); // +1 for terminator

	snprintf(*filename, PATH_MAX, "%s/%s", dir, base_name);

	free(base_name);

	fd = open(*filename, _O_RDWR | _O_CREAT, _S_IREAD | _S_IWRITE);

#else

	snprintf(*filename, PATH_MAX, "%s/%s", dir, template);

	fd = mkstemp(*filename);

#endif

	(void) umask(old_mode);

	if (fd < 1) {

		oscap_seterr(OSCAP_EFAMILY_GLIBC, "mkstemp for %s failed: %s", *filename, strerror(errno));

		free(*filename);

		*filename = NULL;

	}

	return fd;

}

bool

oscap_acquire_url_is_supported(const char *url)

{

	return oscap_str_startswith(url, "http://") || oscap_str_startswith(url, "https://");

}

char *

oscap_acquire_url_to_filename(const char *url)

{

	/* RFC 3986: 2.1. Percent-Encoding */

	char *curl_filename = NULL;

	char *filename = NULL;

	CURL *curl;

	if (curl_global_init(CURL_GLOBAL_ALL) != 0) {

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to initialize libcurl.");

		return NULL;

	}

	curl = curl_easy_init();

	if (curl == NULL) {

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to initialize libcurl.");

		return NULL;

	}

	curl_filename = curl_easy_escape(curl , url , 0);

	if (curl_filename == NULL) {

		curl_easy_cleanup(curl);

		curl_global_cleanup();

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to escape the given url %s", url);

		return NULL;

	}

	filename = oscap_strdup(curl_filename);

	curl_free(curl_filename);

	curl_easy_cleanup(curl);

	curl_global_cleanup();

	return filename;

}

static int _curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)

{

	const char *title;

	switch (type) {

	case CURLINFO_TEXT:

		title = "== cURL info";

		break;

	case CURLINFO_HEADER_OUT:

		title = "=> cURL header (out)";

		break;

	case CURLINFO_HEADER_IN:

		title = "<= cURL header (in)";

		break;

	case CURLINFO_DATA_OUT:

	case CURLINFO_SSL_DATA_OUT:

	case CURLINFO_DATA_IN:

	case CURLINFO_SSL_DATA_IN:

	default:

		return 0;

		break;

	}

	dD("%s: %s", title, data);

	return 0;

}

char* oscap_acquire_url_download(const char *url, size_t* memory_size)

{

	CURL *curl;

	curl = curl_easy_init();

	if (curl == NULL) {

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to initialize libcurl.");

		return NULL;

	}

	CURLcode res;

	res = curl_easy_setopt(curl, CURLOPT_URL, url);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_URL to '%s': %s", url, curl_easy_strerror(res));

		return NULL;

	}

	res = curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_to_memory_callback);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_WRITEFUNCTION to write_to_memory_callback: %s", curl_easy_strerror(res));

		return NULL;

	}

	res = curl_easy_setopt(curl, CURLOPT_ACCEPT_ENCODING, "");

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_ACCEPT_ENCODING to an empty string: %s", curl_easy_strerror(res));

		return NULL;

	}

	res = curl_easy_setopt(curl, CURLOPT_TRANSFER_ENCODING, true);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_TRANSFER_ENCODING to true: %s", curl_easy_strerror(res));

		return NULL;

	}

	res = curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, true);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_FOLLOWLOCATION to true: %s", curl_easy_strerror(res));

		return NULL;

	}

	res = curl_easy_setopt(curl, CURLOPT_VERBOSE, true);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_VERBOSE to true: %s", curl_easy_strerror(res));

		return NULL;

	}

	res = curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, _curl_trace);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_DEBUGFUNCTION to _curl_trace: %s", curl_easy_strerror(res));

		return NULL;

	}

	struct oscap_buffer *buffer = oscap_buffer_new();

	res = curl_easy_setopt(curl, CURLOPT_WRITEDATA, buffer);

	if (res != 0) {

		curl_easy_cleanup(curl);

		oscap_seterr(OSCAP_EFAMILY_NET, "Failed to set CURLOPT_WRITEDATA as buffer: %s", curl_easy_strerror(res));

		oscap_buffer_free(buffer);

		return NULL;

	}

	res = curl_easy_perform(curl);

	curl_easy_cleanup(curl);

	if (res != 0) {

		oscap_seterr(OSCAP_EFAMILY_NET, "Download failed: %s", curl_easy_strerror(res));

		oscap_buffer_free(buffer);

		return NULL;

	}

	*memory_size = oscap_buffer_get_length(buffer);

	char* data = oscap_buffer_bequeath(buffer); // get data and free buffer struct

	return data;

}

size_t write_to_memory_callback(char *ptr, size_t size, size_t nmemb, void *userdata)

{

	size_t new_received_size = size * nmemb; // total size of newly received data

	oscap_buffer_append_binary_data((struct oscap_buffer*)userdata, ptr, new_received_size);

	return new_received_size;

}

char *

oscap_acquire_pipe_to_string(int fd)

{

	struct oscap_string *pipe_string = oscap_string_new();

	char readbuf;

	// FIXME: Read by larger chunks in the future

	while (read(fd, &readbuf, 1) > 0) {

		if (readbuf == '&') {

			// & is a special case, we have to "escape" it manually

			// (all else will eventually get handled by libxml)

			oscap_string_append_string(pipe_string, "&");

		} else {

			oscap_string_append_char(pipe_string, readbuf);

		}

	}

	close(fd);

	return oscap_string_bequeath(pipe_string);

}

char *oscap_acquire_guess_realpath(const char *filepath)

{

	char resolved_name[PATH_MAX];

	char *rpath = oscap_realpath(filepath, resolved_name);

	if (rpath != NULL)

		rpath = oscap_strdup(rpath);

	else {

		// file does not exists, let's try to guess realpath

		// this is not 100% correct, but it is good enough

		char *copy = oscap_strdup(filepath);

		if (copy == NULL) {

			oscap_seterr(OSCAP_EFAMILY_OSCAP, "Cannot guess realpath for %s, directory: cannot allocate memory!", filepath);

			return NULL;

		}

		char *dir_name = oscap_dirname(copy);

		char *real_dir = oscap_realpath(dir_name, resolved_name);

		if (real_dir == NULL) {

			oscap_seterr(OSCAP_EFAMILY_OSCAP, "Cannot guess realpath for %s, directory: %s does not exists!", filepath, dir_name);

			free(copy);

			free(dir_name);

			return NULL;

		}

		free(dir_name);

		char *base_name = oscap_basename((char *)filepath);

		rpath = oscap_sprintf("%s/%s", real_dir, base_name);

		free(base_name);

		free(copy);

	}

	return rpath;

}

int oscap_acquire_mkdir_p(const char *path)

{

	// NOTE: This assumes a UNIX VFS path, C:\\folder\\folder would break it!

	if (strlen(path) > PATH_MAX) {

		return -1;

	}

	else {

		char temp[PATH_MAX + 1]; // +1 for \0

		unsigned int i;

		for (i = 0; i <= strlen(path); i++) {

			if (path[i] == '/' || path[i] == '\0') {

				strncpy(temp, path, i);

				temp[i] = '\0';

				// skip leading '/', we will never be creating the root anyway

				if (strlen(temp) == 0)

					continue;

#ifndef OS_WINDOWS

				if (mkdir(temp, S_IRWXU) != 0 && errno != EEXIST) {

#else

				if (mkdir(temp) != 0 && errno != EEXIST) {

#endif

					oscap_seterr(OSCAP_EFAMILY_GLIBC,

						"Error making directory '%s', while doing recursive mkdir for '%s', error was '%s'.",

						temp, path, strerror(errno));

					return -1;

				}

			}

		}

		return 0;

	}

}

int oscap_acquire_ensure_parent_dir(const char *filepath)

{

	char *filepath_cpy = oscap_strdup(filepath);

	char *dirpath = oscap_dirname(filepath_cpy);

	int ret = oscap_acquire_mkdir_p(dirpath);

	if (ret != 0) {

		oscap_seterr(OSCAP_EFAMILY_GLIBC, "Error making directory '%s' to ensure correct path of '%s'.", dirpath, filepath);

	}

	free(dirpath);

	free(filepath_cpy);

	return ret;

}