The Tor Browser: comparison modules/libmar/src/mar

--1:000000000000
+:1e5e847b06f5
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include "mar_private.h"
+#include "mar_cmdline.h"
+#include "mar.h"
+#ifdef XP_WIN
+#include <winsock2.h>
+#else
+#include <netinet/in.h>
+#include <unistd.h>
+#endif
+struct MarItemStack {
+void *head;
+uint32_t size_used;
+uint32_t size_allocated;
+uint32_t last_offset;
+};
+/**
+* Push a new item onto the stack of items.  The stack is a single block
+* of memory.
+*/
+static int mar_push(struct MarItemStack *stack, uint32_t length, uint32_t flags,
+const char *name) {
+int namelen;
+uint32_t n_offset, n_length, n_flags;
+uint32_t size;
+char *data;
+namelen = strlen(name);
+size = MAR_ITEM_SIZE(namelen);
+if (stack->size_allocated - stack->size_used < size) {
+/* increase size of stack */
+size_t size_needed = ROUND_UP(stack->size_used + size, BLOCKSIZE);
+stack->head = realloc(stack->head, size_needed);
+if (!stack->head)
+return -1;
+stack->size_allocated = size_needed;
+}
+data = (((char *) stack->head) + stack->size_used);
+n_offset = htonl(stack->last_offset);
+n_length = htonl(length);
+n_flags = htonl(flags);
+memcpy(data, &n_offset, sizeof(n_offset));
+data += sizeof(n_offset);
+memcpy(data, &n_length, sizeof(n_length));
+data += sizeof(n_length);
+memcpy(data, &n_flags, sizeof(n_flags));
+data += sizeof(n_flags);
+memcpy(data, name, namelen + 1);
+stack->size_used += size;
+stack->last_offset += length;
+return 0;
+}
+static int mar_concat_file(FILE *fp, const char *path) {
+FILE *in;
+char buf[BLOCKSIZE];
+size_t len;
+int rv = 0;
+in = fopen(path, "rb");
+if (!in) {
+fprintf(stderr, "ERROR: could not open file in mar_concat_file()\n");
+perror(path);
+return -1;
+}
+while ((len = fread(buf, 1, BLOCKSIZE, in)) > 0) {
+if (fwrite(buf, len, 1, fp) != 1) {
+rv = -1;
+break;
+}
+}
+fclose(in);
+return rv;
+}
+/**
+* Writes out the product information block to the specified file.
+*
+* @param fp           The opened MAR file being created.
+* @param stack        A pointer to the MAR item stack being used to create
+*                     the MAR
+* @param infoBlock    The product info block to store in the file.
+* @return 0 on success.
+*/
+static int
+mar_concat_product_info_block(FILE *fp,
+struct MarItemStack *stack,
+struct ProductInformationBlock *infoBlock)
+{
+char buf[PIB_MAX_MAR_CHANNEL_ID_SIZE + PIB_MAX_PRODUCT_VERSION_SIZE];
+uint32_t additionalBlockID = 1, infoBlockSize, unused;
+if (!fp || !infoBlock ||
+!infoBlock->MARChannelID ||
+!infoBlock->productVersion) {
+return -1;
+}
+/* The MAR channel name must be < 64 bytes per the spec */
+if (strlen(infoBlock->MARChannelID) > PIB_MAX_MAR_CHANNEL_ID_SIZE) {
+return -1;
+}
+/* The product version must be < 32 bytes per the spec */
+if (strlen(infoBlock->productVersion) > PIB_MAX_PRODUCT_VERSION_SIZE) {
+return -1;
+}
+/* Although we don't need the product information block size to include the
+maximum MAR channel name and product version, we allocate the maximum
+amount to make it easier to modify the MAR file for repurposing MAR files
+to different MAR channels. + 2 is for the NULL terminators. */
+infoBlockSize = sizeof(infoBlockSize) +
+sizeof(additionalBlockID) +
+PIB_MAX_MAR_CHANNEL_ID_SIZE +
+PIB_MAX_PRODUCT_VERSION_SIZE + 2;
+if (stack) {
+stack->last_offset += infoBlockSize;
+}
+/* Write out the product info block size */
+infoBlockSize = htonl(infoBlockSize);
+if (fwrite(&infoBlockSize,
+sizeof(infoBlockSize), 1, fp) != 1) {
+return -1;
+}
+infoBlockSize = ntohl(infoBlockSize);
+/* Write out the product info block ID */
+additionalBlockID = htonl(additionalBlockID);
+if (fwrite(&additionalBlockID,
+sizeof(additionalBlockID), 1, fp) != 1) {
+return -1;
+}
+additionalBlockID = ntohl(additionalBlockID);
+/* Write out the channel name and NULL terminator */
+if (fwrite(infoBlock->MARChannelID,
+strlen(infoBlock->MARChannelID) + 1, 1, fp) != 1) {
+return -1;
+}
+/* Write out the product version string and NULL terminator */
+if (fwrite(infoBlock->productVersion,
+strlen(infoBlock->productVersion) + 1, 1, fp) != 1) {
+return -1;
+}
+/* Write out the rest of the block that is unused */
+unused = infoBlockSize - (sizeof(infoBlockSize) +
+sizeof(additionalBlockID) +
+strlen(infoBlock->MARChannelID) +
+strlen(infoBlock->productVersion) + 2);
+memset(buf, 0, sizeof(buf));
+if (fwrite(buf, unused, 1, fp) != 1) {
+return -1;
+}
+return 0;
+}
+/**
+* Refreshes the product information block with the new information.
+* The input MAR must not be signed or the function call will fail.
+*
+* @param path             The path to the MAR file whose product info block
+*                         should be refreshed.
+* @param infoBlock        Out parameter for where to store the result to
+* @return 0 on success, -1 on failure
+*/
+int
+refresh_product_info_block(const char *path,
+struct ProductInformationBlock *infoBlock)
+{
+FILE *fp ;
+int rv;
+uint32_t numSignatures, additionalBlockSize, additionalBlockID,
+offsetAdditionalBlocks, numAdditionalBlocks, i;
+int additionalBlocks, hasSignatureBlock;
+int64_t oldPos;
+rv = get_mar_file_info(path,
+&hasSignatureBlock,
+&numSignatures,
+&additionalBlocks,
+&offsetAdditionalBlocks,
+&numAdditionalBlocks);
+if (rv) {
+fprintf(stderr, "ERROR: Could not obtain MAR information.\n");
+return -1;
+}
+if (hasSignatureBlock && numSignatures) {
+fprintf(stderr, "ERROR: Cannot refresh a signed MAR\n");
+return -1;
+}
+fp = fopen(path, "r+b");
+if (!fp) {
+fprintf(stderr, "ERROR: could not open target file: %s\n", path);
+return -1;
+}
+if (fseeko(fp, offsetAdditionalBlocks, SEEK_SET)) {
+fprintf(stderr, "ERROR: could not seek to additional blocks\n");
+fclose(fp);
+return -1;
+}
+for (i = 0; i < numAdditionalBlocks; ++i) {
+/* Get the position of the start of this block */
+oldPos = ftello(fp);
+/* Read the additional block size */
+if (fread(&additionalBlockSize,
+sizeof(additionalBlockSize),
+1, fp) != 1) {
+return -1;
+}
+additionalBlockSize = ntohl(additionalBlockSize);
+/* Read the additional block ID */
+if (fread(&additionalBlockID,
+sizeof(additionalBlockID),
+1, fp) != 1) {
+return -1;
+}
+additionalBlockID = ntohl(additionalBlockID);
+if (PRODUCT_INFO_BLOCK_ID == additionalBlockID) {
+if (fseeko(fp, oldPos, SEEK_SET)) {
+fprintf(stderr, "Could not seek back to Product Information Block\n");
+fclose(fp);
+return -1;
+}
+if (mar_concat_product_info_block(fp, NULL, infoBlock)) {
+fprintf(stderr, "Could not concat Product Information Block\n");
+fclose(fp);
+return -1;
+}
+fclose(fp);
+return 0;
+} else {
+/* This is not the additional block you're looking for. Move along. */
+if (fseek(fp, additionalBlockSize, SEEK_CUR)) {
+fprintf(stderr, "ERROR: Could not seek past current block.\n");
+fclose(fp);
+return -1;
+}
+}
+}
+/* If we had a product info block we would have already returned */
+fclose(fp);
+fprintf(stderr, "ERROR: Could not refresh because block does not exist\n");
+return -1;
+}
+/**
+* Create a MAR file from a set of files.
+* @param dest      The path to the file to create.  This path must be
+*                  compatible with fopen.
+* @param numfiles  The number of files to store in the archive.
+* @param files     The list of null-terminated file paths.  Each file
+*                  path must be compatible with fopen.
+* @param infoBlock The information to store in the product information block.
+* @return A non-zero value if an error occurs.
+*/
+int mar_create(const char *dest, int
+num_files, char **files,
+struct ProductInformationBlock *infoBlock) {
+struct MarItemStack stack;
+uint32_t offset_to_index = 0, size_of_index,
+numSignatures, numAdditionalSections;
+uint64_t sizeOfEntireMAR = 0;
+struct stat st;
+FILE *fp;
+int i, rv = -1;
+memset(&stack, 0, sizeof(stack));
+fp = fopen(dest, "wb");
+if (!fp) {
+fprintf(stderr, "ERROR: could not create target file: %s\n", dest);
+return -1;
+}
+if (fwrite(MAR_ID, MAR_ID_SIZE, 1, fp) != 1)
+goto failure;
+if (fwrite(&offset_to_index, sizeof(uint32_t), 1, fp) != 1)
+goto failure;
+stack.last_offset = MAR_ID_SIZE +
+sizeof(offset_to_index) +
+sizeof(numSignatures) +
+sizeof(numAdditionalSections) +
+sizeof(sizeOfEntireMAR);
+/* We will circle back on this at the end of the MAR creation to fill it */
+if (fwrite(&sizeOfEntireMAR, sizeof(sizeOfEntireMAR), 1, fp) != 1) {
+goto failure;
+}
+/* Write out the number of signatures, for now only at most 1 is supported */
+numSignatures = 0;
+if (fwrite(&numSignatures, sizeof(numSignatures), 1, fp) != 1) {
+goto failure;
+}
+/* Write out the number of additional sections, for now just 1
+for the product info block */
+numAdditionalSections = htonl(1);
+if (fwrite(&numAdditionalSections,
+sizeof(numAdditionalSections), 1, fp) != 1) {
+goto failure;
+}
+numAdditionalSections = ntohl(numAdditionalSections);
+if (mar_concat_product_info_block(fp, &stack, infoBlock)) {
+goto failure;
+}
+for (i = 0; i < num_files; ++i) {
+if (stat(files[i], &st)) {
+fprintf(stderr, "ERROR: file not found: %s\n", files[i]);
+goto failure;
+}
+if (mar_push(&stack, st.st_size, st.st_mode & 0777, files[i]))
+goto failure;
+/* concatenate input file to archive */
+if (mar_concat_file(fp, files[i]))
+goto failure;
+}
+/* write out the index (prefixed with length of index) */
+size_of_index = htonl(stack.size_used);
+if (fwrite(&size_of_index, sizeof(size_of_index), 1, fp) != 1)
+goto failure;
+if (fwrite(stack.head, stack.size_used, 1, fp) != 1)
+goto failure;
+/* To protect against invalid MAR files, we assumes that the MAR file
+size is less than or equal to MAX_SIZE_OF_MAR_FILE. */
+if (ftell(fp) > MAX_SIZE_OF_MAR_FILE) {
+goto failure;
+}
+/* write out offset to index file in network byte order */
+offset_to_index = htonl(stack.last_offset);
+if (fseek(fp, MAR_ID_SIZE, SEEK_SET))
+goto failure;
+if (fwrite(&offset_to_index, sizeof(offset_to_index), 1, fp) != 1)
+goto failure;
+offset_to_index = ntohl(stack.last_offset);
+sizeOfEntireMAR = ((uint64_t)stack.last_offset) +
+stack.size_used +
+sizeof(size_of_index);
+sizeOfEntireMAR = HOST_TO_NETWORK64(sizeOfEntireMAR);
+if (fwrite(&sizeOfEntireMAR, sizeof(sizeOfEntireMAR), 1, fp) != 1)
+goto failure;
+sizeOfEntireMAR = NETWORK_TO_HOST64(sizeOfEntireMAR);
+rv = 0;
+failure:
+if (stack.head)
+free(stack.head);
+fclose(fp);
+if (rv)
+remove(dest);
+return rv;
+}

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comparison: modules/libmar/src/mar_create.c

modules/libmar/src/mar_create.c