/*
 * idevicerestore.c
 * Restore device firmware and filesystem
 *
 * Copyright (c) 2010 Joshua Hill. 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
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
#include <plist/plist.h>
#include <libirecovery.h>
#include <libimobiledevice/restore.h>
#include <libimobiledevice/lockdown.h>
#include <libimobiledevice/libimobiledevice.h>

#include "dfu.h"
#include "tss.h"
#include "img3.h"
#include "ipsw.h"
#include "normal.h"
#include "restore.h"
#include "recovery.h"
#include "idevicerestore.h"

int idevicerestore_quit = 0;
int idevicerestore_debug = 0;
int idevicerestore_erase = 0;
int idevicerestore_custom = 0;
int idevicerestore_verbose = 0;
int idevicerestore_exclude = 0;
int idevicerestore_mode = MODE_UNKNOWN;
idevicerestore_device_t* idevicerestore_device = NULL;

static struct option long_opts[] = {
	{ "uuid",    required_argument,  NULL, 'u' },
	{ "debug",   no_argument,        NULL, 'd' },
	{ "verbose", no_argument,        NULL, 'v' },
	{ "help",    no_argument,        NULL, 'h' },
	{ "erase",   no_argument,        NULL, 'e' },
	{ "custom",  no_argument,        NULL, 'c' },
	{ "exclude", no_argument,        NULL, 'x' },
	{ NULL, 0, NULL, 0}
};

void usage(int argc, char* argv[]) {
	char *name = strrchr(argv[0], '/');
	printf("Usage: %s [OPTIONS] FILE\n", (name ? name + 1 : argv[0]));
	printf("Restore/upgrade IPSW firmware FILE to an iPhone/iPod Touch.\n");
	printf("  -u, --uuid UUID\ttarget specific device by its 40-digit device UUID\n");
	printf("  -d, --debug\t\tenable communication debugging\n");
	printf("  -v, --verbose\t\tenable verbose output\n");
	printf("  -h, --help\t\tprints usage information\n");
	printf("  -e, --erase\t\tperform a full restore, erasing all data\n");
	printf("  -c, --custom\t\trestore with a custom firmware\n");
	printf("  -x, --exclude\t\texclude nor/baseband upgrade\n");
	printf("\n");
}

int get_build_count(plist_t buildmanifest) {
	// fetch build identities array from BuildManifest
	plist_t build_identities_array = plist_dict_get_item(buildmanifest, "BuildIdentities");
	if (!build_identities_array || plist_get_node_type(build_identities_array) != PLIST_ARRAY) {
		error("ERROR: Unable to find build identities node\n");
		return -1;
	}

	// check and make sure this identity exists in buildmanifest
	return plist_array_get_size(build_identities_array);
}

const char* get_build_name(plist_t build_identity, int identity) {
	plist_t manifest_node = plist_dict_get_item(build_identity, "Manifest");
	if (!manifest_node || plist_get_node_type(manifest_node) != PLIST_DICT) {
		error("ERROR: Unable to find restore manifest\n");
		return NULL;
	}

	plist_t filesystem_info_node = plist_dict_get_item(manifest_node, "Info");
	if (!filesystem_info_node || plist_get_node_type(filesystem_info_node) != PLIST_DICT) {
		error("ERROR: Unable to find filesystem info node\n");
		return NULL;
	}
	return NULL;
}

int main(int argc, char* argv[]) {
	int opt = 0;
	int optindex = 0;
	char* ipsw = NULL;
	char* uuid = NULL;
	uint64_t ecid = 0;
	while ((opt = getopt_long(argc, argv, "vdhcexu:", long_opts, &optindex)) > 0) {
		switch (opt) {
		case 'h':
			usage(argc, argv);
			break;

		case 'd':
			idevicerestore_debug = 1;
			break;

		case 'e':
			idevicerestore_erase = 1;
			break;

		case 'c':
			idevicerestore_custom = 1;
			break;

		case 'x':
			idevicerestore_exclude = 1;
			break;

		case 'v':
			idevicerestore_verbose = 1;
			break;

		case 'u':
			uuid = optarg;
			break;

		default:
			usage(argc, argv);
			return -1;
		}
	}

	argc -= optind;
	argv += optind;

	if (argc == 1) {
		ipsw = argv[0];
	} else {
		usage(argc, argv);
		return -1;
	}

	if(idevicerestore_debug) {
		idevice_set_debug_level(5);
	}

	// check which mode the device is currently in so we know where to start
	idevicerestore_mode = check_mode(uuid);
	if (idevicerestore_mode < 0) {
		error("ERROR: Unable to discover current device state\n");
		return -1;
	}

	// discover the device type
	int id = check_device(uuid);
	if (id < 0) {
		error("ERROR: Unable to discover device type\n");
		return -1;
	}
	idevicerestore_device = &idevicerestore_devices[id];

	if (idevicerestore_mode == MODE_RESTORE) {
		if (restore_reboot(uuid) < 0) {
			error("ERROR: Unable to exit restore mode\n");
			return -1;
		}
	}

	// extract buildmanifest
	plist_t buildmanifest = NULL;
	info("Extracting BuildManifest from IPSW\n");
	if (extract_buildmanifest(ipsw, &buildmanifest) < 0) {
		error("ERROR: Unable to extract BuildManifest from %s\n", ipsw);
		return -1;
	}

	// devices are listed in order from oldest to newest
	// so we'll need their ECID
	if (idevicerestore_device->device_id > DEVICE_IPOD2G) {
		info("Creating TSS request\n");
		// fetch the device's ECID for the TSS request
		if (get_ecid(uuid, &ecid) < 0 || ecid == 0) {
			error("ERROR: Unable to find device ECID\n");
			return -1;
		}
		debug("Found ECID %llu\n", ecid);
	}

	// choose whether this is an upgrade or a restore (default to upgrade)
	plist_t tss = NULL;
	plist_t build_identity = NULL;
	if (idevicerestore_erase) {
		build_identity = get_build_identity(buildmanifest, 0);
		if (build_identity == NULL) {
			error("ERROR: Unable to find build any identities\n");
			plist_free(buildmanifest);
			return -1;
		}

	} else {
		// loop through all build identities in the build manifest
		// and list the valid ones
		int i = 0;
		int valid_builds = 0;
		int build_count = get_build_count(buildmanifest);
		for(i = 0; i < build_count; i++) {
			if (idevicerestore_device->device_id > DEVICE_IPOD2G) {
				if (get_shsh_blobs(ecid, buildmanifest, &tss) < 0) {
					// if this fails then no SHSH blobs have been saved
					// for this build identity, so check the next one
					continue;
				}
				info("[%d] %s\n", i, get_build_name(buildmanifest, i));
				valid_builds++;
			}
		}
	}

	// devices are listed in order from oldest to newest
	// devices that come after iPod2g require personalized firmwares
	plist_t tss_request = NULL;
	if (idevicerestore_device->device_id > DEVICE_IPOD2G) {
		info("Creating TSS request\n");
		// fetch the device's ECID for the TSS request
		if (get_ecid(uuid, &ecid) < 0 || ecid == 0) {
			error("ERROR: Unable to find device ECID\n");
			return -1;
		}
		info("Found ECID %llu\n", ecid);

		// fetch the SHSH blobs for this build identity
		if (get_shsh_blobs(ecid, build_identity, &tss) < 0) {
			// this might fail if the TSS server doesn't have the saved blobs for the
			// update identity, so go ahead and try again with the restore identity
			if (idevicerestore_erase != 1) {
				info("Unable to fetch SHSH blobs for upgrade, retrying with full restore\n");
				build_identity = get_build_identity(buildmanifest, 0);
				if (build_identity == NULL) {
					error("ERROR: Unable to find restore identity\n");
					plist_free(buildmanifest);
					return -1;
				}

				if (get_shsh_blobs(ecid, build_identity, &tss) < 0) {
					// if this fails then no SHSH blobs have been saved for this firmware
					error("ERROR: Unable to fetch SHSH blobs for this firmware\n");
					plist_free(buildmanifest);
					return -1;
				}

			} else {
				error("ERROR: Unable to fetch SHSH blobs for this firmware\n");
				plist_free(buildmanifest);
				return -1;
			}
		}
	}

	// Extract filesystem from IPSW and return its name
	char* filesystem = NULL;
	if (extract_filesystem(ipsw, build_identity, &filesystem) < 0) {
		error("ERROR: Unable to extract filesystem from IPSW\n");
		if (tss)
			plist_free(tss);
		plist_free(buildmanifest);
		return -1;
	}

	// if the device is in normal mode, place device into recovery mode
	if (idevicerestore_mode == MODE_NORMAL) {
		info("Entering recovery mode...\n");
		if (normal_enter_recovery(uuid) < 0) {
			error("ERROR: Unable to place device into recovery mode\n");
			if (tss)
				plist_free(tss);
			plist_free(buildmanifest);
			return -1;
		}
	}

	// if the device is in DFU mode, place device into recovery mode
	if (idevicerestore_mode == MODE_DFU) {
		if (dfu_enter_recovery(ipsw, tss) < 0) {
			error("ERROR: Unable to place device into recovery mode\n");
			plist_free(buildmanifest);
			if (tss)
				plist_free(tss);
			return -1;
		}
	}

	// if the device is in recovery mode, place device into restore mode
	if (idevicerestore_mode == MODE_RECOVERY) {
		if (recovery_enter_restore(uuid, ipsw, tss) < 0) {
			error("ERROR: Unable to place device into restore mode\n");
			plist_free(buildmanifest);
			if (tss)
				plist_free(tss);
			return -1;
		}
	}

	// device is finally in restore mode, let's do this
	if (idevicerestore_mode == MODE_RESTORE) {
		info("Restoring device... \n");
		if (restore_device(uuid, ipsw, tss, filesystem) < 0) {
			error("ERROR: Unable to restore device\n");
			return -1;
		}
	}

	// device has finished restoring, lets see if we need to activate
	if (idevicerestore_mode == MODE_NORMAL) {
		info("Checking activation status\n");
		int activation = activate_check_status(uuid);
		if (activation < 0) {
			error("ERROR: Unable to check activation status\n");
			return -1;
		}

		if (activation == 0) {
			info("Activating device... \n");
			if (activate_device(uuid) < 0) {
				error("ERROR: Unable to activate device\n");
				return -1;
			}
		}
	}

	info("Cleaning up...\n");
	if (filesystem)
		unlink(filesystem);

	info("DONE\n");
	return 0;
}

int check_mode(const char* uuid) {
	int mode = MODE_UNKNOWN;

	if (recovery_check_mode() == 0) {
		info("Found device in recovery mode\n");
		mode = MODE_RECOVERY;
	}

	else if (dfu_check_mode() == 0) {
		info("Found device in DFU mode\n");
		mode = MODE_DFU;
	}

	else if (normal_check_mode(uuid) == 0) {
		info("Found device in normal mode\n");
		mode = MODE_NORMAL;
	}

	else if (restore_check_mode(uuid) == 0) {
		info("Found device in restore mode\n");
		mode = MODE_RESTORE;
	}

	return mode;
}

int check_device(const char* uuid) {
	int device = DEVICE_UNKNOWN;
	uint32_t bdid = 0;
	uint32_t cpid = 0;

	switch (idevicerestore_mode) {
	case MODE_RESTORE:
		device = restore_check_device(uuid);
		if (device < 0) {
			device = DEVICE_UNKNOWN;
		}
		break;

	case MODE_NORMAL:
		device = normal_check_device(uuid);
		if (device < 0) {
			device = DEVICE_UNKNOWN;
		}
		break;

	case MODE_DFU:
	case MODE_RECOVERY:
		if (get_cpid(uuid, &cpid) < 0) {
			error("ERROR: Unable to get device CPID\n");
			break;
		}

		switch (cpid) {
		case CPID_IPHONE2G:
			// iPhone1,1 iPhone1,2 and iPod1,1 all share the same ChipID
			//   so we need to check the BoardID
			if (get_bdid(uuid, &bdid) < 0) {
				error("ERROR: Unable to get device BDID\n");
				break;
			}

			switch (bdid) {
			case BDID_IPHONE2G:
				device = DEVICE_IPHONE2G;
				break;

			case BDID_IPHONE3G:
				device = DEVICE_IPHONE3G;
				break;

			case BDID_IPOD1G:
				device = DEVICE_IPOD1G;
				break;

			default:
				device = DEVICE_UNKNOWN;
				break;
			}
			break;

		case CPID_IPHONE3GS:
			device = DEVICE_IPHONE3GS;
			break;

		case CPID_IPOD2G:
			device = DEVICE_IPOD2G;
			break;

		case CPID_IPOD3G:
			device = DEVICE_IPOD3G;
			break;

		case CPID_IPAD1G:
			device = DEVICE_IPAD1G;
			break;

		default:
			device = DEVICE_UNKNOWN;
			break;
		}
		break;

	default:
		device = DEVICE_UNKNOWN;
		break;

	}

	return device;
}

int get_bdid(const char* uuid, uint32_t* bdid) {
	switch (idevicerestore_mode) {
	case MODE_NORMAL:
		if (normal_get_bdid(uuid, bdid) < 0) {
			*bdid = -1;
			return -1;
		}
		break;

	case MODE_DFU:
	case MODE_RECOVERY:
		if (recovery_get_bdid(bdid) < 0) {
			*bdid = -1;
			return -1;
		}
		break;

	default:
		error("ERROR: Device is in an invalid state\n");
		return -1;
	}

	return 0;
}

int get_cpid(const char* uuid, uint32_t* cpid) {
	switch (idevicerestore_mode) {
	case MODE_NORMAL:
		if (normal_get_cpid(uuid, cpid) < 0) {
			*cpid = 0;
			return -1;
		}
		break;

	case MODE_DFU:
	case MODE_RECOVERY:
		if (recovery_get_cpid(cpid) < 0) {
			*cpid = 0;
			return -1;
		}
		break;

	default:
		error("ERROR: Device is in an invalid state\n");
		return -1;
	}

	return 0;
}

int get_ecid(const char* uuid, uint64_t* ecid) {
	switch (idevicerestore_mode) {
	case MODE_NORMAL:
		if (normal_get_ecid(uuid, ecid) < 0) {
			*ecid = 0;
			return -1;
		}
		break;

	case MODE_DFU:
	case MODE_RECOVERY:
		if (recovery_get_ecid(ecid) < 0) {
			*ecid = 0;
			return -1;
		}
		break;

	default:
		error("ERROR: Device is in an invalid state\n");
		return -1;
	}

	return 0;
}

int extract_buildmanifest(const char* ipsw, plist_t* buildmanifest) {
	int size = 0;
	char* data = NULL;
	int device = idevicerestore_device->device_id;
	if (device >= DEVICE_IPHONE2G && device <= DEVICE_IPOD2G) {
		// Older devices that don't require personalized firmwares use BuildManifesto.plist
		if (ipsw_extract_to_memory(ipsw, "BuildManifesto.plist", &data, &size) < 0) {
			return -1;
		}

	} else if (device >= DEVICE_IPHONE3GS && device <= DEVICE_IPAD1G) {
		// Whereas newer devices that do require personalized firmwares use BuildManifest.plist
		if (ipsw_extract_to_memory(ipsw, "BuildManifest.plist", &data, &size) < 0) {
			return -1;
		}

	} else {
		return -1;
	}

	plist_from_xml(data, size, buildmanifest);
	return 0;
}

plist_t get_build_identity(plist_t buildmanifest, uint32_t identity) {
	// fetch build identities array from BuildManifest
	plist_t build_identities_array = plist_dict_get_item(buildmanifest, "BuildIdentities");
	if (!build_identities_array || plist_get_node_type(build_identities_array) != PLIST_ARRAY) {
		error("ERROR: Unable to find build identities node\n");
		return NULL;
	}

	// check and make sure this identity exists in buildmanifest
	if (identity >= plist_array_get_size(build_identities_array)) {
		return NULL;
	}

	plist_t build_identity = plist_array_get_item(build_identities_array, identity);
	if (!build_identity || plist_get_node_type(build_identity) != PLIST_DICT) {
		error("ERROR: Unable to find build identities node\n");
		return NULL;
	}

	return plist_copy(build_identity);
}

int get_shsh_blobs(uint64_t ecid, plist_t build_identity, plist_t* tss) {
	plist_t request = NULL;
	plist_t response = NULL;
	*tss = NULL;

	request = tss_create_request(build_identity, ecid);
	if (request == NULL) {
		error("ERROR: Unable to create TSS request\n");
		return -1;
	}

	info("Sending TSS request\n");
	response = tss_send_request(request);
	if (response == NULL) {
		plist_free(request);
		return -1;
	}

	plist_free(request);
	*tss = response;
	return 0;
}

int extract_filesystem(const char* ipsw, plist_t build_identity, char** filesystem) {
	char* filename = NULL;

	plist_t manifest_node = plist_dict_get_item(build_identity, "Manifest");
	if (!manifest_node || plist_get_node_type(manifest_node) != PLIST_DICT) {
		error("ERROR: Unable to find manifest node\n");
		return -1;
	}

	plist_t filesystem_node = plist_dict_get_item(manifest_node, "OS");
	if (!filesystem_node || plist_get_node_type(filesystem_node) != PLIST_DICT) {
		error("ERROR: Unable to find filesystem node\n");
		return -1;
	}

	plist_t filesystem_info_node = plist_dict_get_item(filesystem_node, "Info");
	if (!filesystem_info_node || plist_get_node_type(filesystem_info_node) != PLIST_DICT) {
		error("ERROR: Unable to find filesystem info node\n");
		return -1;
	}

	plist_t filesystem_info_path_node = plist_dict_get_item(filesystem_info_node, "Path");
	if (!filesystem_info_path_node || plist_get_node_type(filesystem_info_path_node) != PLIST_STRING) {
		error("ERROR: Unable to find filesystem info path node\n");
		return -1;
	}
	plist_get_string_val(filesystem_info_path_node, &filename);

	info("Extracting filesystem from IPSW\n");
	if (ipsw_extract_to_file(ipsw, filename, filename) < 0) {
		error("ERROR: Unable to extract filesystem\n");
		return -1;
	}

	*filesystem = filename;
	return 0;
}

int get_signed_component(const char* ipsw, plist_t tss, const char* path, char** data, uint32_t* size) {
	img3_file* img3 = NULL;
	uint32_t component_size = 0;
	char* component_data = NULL;
	char* component_blob = NULL;
	char* component_name = NULL;

	component_name = strrchr(path, '/');
	if (component_name != NULL) component_name++;
	else component_name = (char*) path;

	info("Extracting %s\n", component_name);
	if (ipsw_extract_to_memory(ipsw, path, &component_data, &component_size) < 0) {
		error("ERROR: Unable to extract %s from %s\n", component_name, ipsw);
		return -1;
	}

	img3 = img3_parse_file(component_data, component_size);
	if (img3 == NULL) {
		error("ERROR: Unable to parse IMG3: %s\n", component_name);
		free(component_data);
		return -1;
	}
	free(component_data);

	if (tss_get_blob_by_path(tss, path, &component_blob) < 0) {
		error("ERROR: Unable to get SHSH blob for TSS %s entry\n", component_name);
		img3_free(img3);
		return -1;
	}

	if (idevicerestore_device->device_id > DEVICE_IPOD2G && idevicerestore_custom == 0) {
		if (img3_replace_signature(img3, component_blob) < 0) {
			error("ERROR: Unable to replace IMG3 signature\n");
			free(component_blob);
			img3_free(img3);
			return -1;
		}
	}
	free(component_blob);

	if (img3_get_data(img3, &component_data, &component_size) < 0) {
		error("ERROR: Unable to reconstruct IMG3\n");
		img3_free(img3);
		return -1;
	}
	img3_free(img3);

	if (idevicerestore_debug) {
		write_file(component_name, component_data, component_size);
	}

	*data = component_data;
	*size = component_size;
	return 0;
}

int write_file(const char* filename, const void* data, size_t size) {
	size_t bytes = 0;
	FILE* file = NULL;

	info("Writing data to %s\n", filename);
	file = fopen(filename, "wb");
	if (file == NULL) {
		error("read_file: Unable to open file %s\n", filename);
		return -1;
	}

	bytes = fwrite(data, 1, size, file);
	fclose(file);

	if (bytes != size) {
		error("ERROR: Unable to write entire file: %s: %d %d\n", filename, bytes, size);
		return -1;
	}

	return size;
}

int read_file(const char* filename, char** data, uint32_t* size) {
	size_t bytes = 0;
	size_t length = 0;
	FILE* file = NULL;
	char* buffer = NULL;
	debug("Reading data from %s\n", filename);

	*size = 0;
	*data = NULL;

	file = fopen(filename, "rb");
	if (file == NULL) {
		error("read_file: File %s not found\n", filename);
		return -1;
	}

	fseek(file, 0, SEEK_END);
	length = ftell(file);
	rewind(file);

	buffer = (char*) malloc(length);
	if(buffer == NULL) {
		error("ERROR: Out of memory\n");
		fclose(file);
		return -1;
	}
	bytes = fread(buffer, 1, length, file);
	fclose(file);

	if(bytes != length) {
		error("ERROR: Unable to read entire file\n");
		free(buffer);
		return -1;
	}

	*size = length;
	*data = buffer;
	return 0;
}