diff options
Diffstat (limited to 'modules/libmar/src/mar_create.c')
| -rw-r--r-- | modules/libmar/src/mar_create.c | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/modules/libmar/src/mar_create.c b/modules/libmar/src/mar_create.c new file mode 100644 index 0000000000..0ac2bf7b2c --- /dev/null +++ b/modules/libmar/src/mar_create.c @@ -0,0 +1,391 @@ +/* -*- 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) { + fclose(fp); + return -1; + } + additionalBlockSize = ntohl(additionalBlockSize); + + /* Read the additional block ID */ + if (fread(&additionalBlockID, sizeof(additionalBlockID), 1, fp) != 1) { + fclose(fp); + 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; +} |