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-rw-r--r--modules/libmar/src/mar_read.c577
1 files changed, 577 insertions, 0 deletions
diff --git a/modules/libmar/src/mar_read.c b/modules/libmar/src/mar_read.c
new file mode 100644
index 000000000..17744cdfc
--- /dev/null
+++ b/modules/libmar/src/mar_read.c
@@ -0,0 +1,577 @@
+/* -*- 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 <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include "mar_private.h"
+#include "mar.h"
+
+#ifdef XP_WIN
+#include <winsock2.h>
+#else
+#include <netinet/in.h>
+#endif
+
+
+/* this is the same hash algorithm used by nsZipArchive.cpp */
+static uint32_t mar_hash_name(const char *name) {
+ uint32_t val = 0;
+ unsigned char* c;
+
+ for (c = (unsigned char *) name; *c; ++c)
+ val = val*37 + *c;
+
+ return val % TABLESIZE;
+}
+
+static int mar_insert_item(MarFile *mar, const char *name, int namelen,
+ uint32_t offset, uint32_t length, uint32_t flags) {
+ MarItem *item, *root;
+ uint32_t hash;
+
+ item = (MarItem *) malloc(sizeof(MarItem) + namelen);
+ if (!item)
+ return -1;
+ item->next = NULL;
+ item->offset = offset;
+ item->length = length;
+ item->flags = flags;
+ memcpy(item->name, name, namelen + 1);
+
+ hash = mar_hash_name(name);
+
+ root = mar->item_table[hash];
+ if (!root) {
+ mar->item_table[hash] = item;
+ } else {
+ /* append item */
+ while (root->next)
+ root = root->next;
+ root->next = item;
+ }
+ return 0;
+}
+
+static int mar_consume_index(MarFile *mar, char **buf, const char *buf_end) {
+ /*
+ * Each item has the following structure:
+ * uint32_t offset (network byte order)
+ * uint32_t length (network byte order)
+ * uint32_t flags (network byte order)
+ * char name[N] (where N >= 1)
+ * char null_byte;
+ */
+ uint32_t offset;
+ uint32_t length;
+ uint32_t flags;
+ const char *name;
+ int namelen;
+
+ if ((buf_end - *buf) < (int)(3*sizeof(uint32_t) + 2))
+ return -1;
+
+ memcpy(&offset, *buf, sizeof(offset));
+ *buf += sizeof(offset);
+
+ memcpy(&length, *buf, sizeof(length));
+ *buf += sizeof(length);
+
+ memcpy(&flags, *buf, sizeof(flags));
+ *buf += sizeof(flags);
+
+ offset = ntohl(offset);
+ length = ntohl(length);
+ flags = ntohl(flags);
+
+ name = *buf;
+ /* find namelen; must take care not to read beyond buf_end */
+ while (**buf) {
+ /* buf_end points one byte past the end of buf's allocation */
+ if (*buf == (buf_end - 1))
+ return -1;
+ ++(*buf);
+ }
+ namelen = (*buf - name);
+ /* must ensure that namelen is valid */
+ if (namelen < 0) {
+ return -1;
+ }
+ /* consume null byte */
+ if (*buf == buf_end)
+ return -1;
+ ++(*buf);
+
+ return mar_insert_item(mar, name, namelen, offset, length, flags);
+}
+
+static int mar_read_index(MarFile *mar) {
+ char id[MAR_ID_SIZE], *buf, *bufptr, *bufend;
+ uint32_t offset_to_index, size_of_index;
+
+ /* verify MAR ID */
+ if (fread(id, MAR_ID_SIZE, 1, mar->fp) != 1)
+ return -1;
+ if (memcmp(id, MAR_ID, MAR_ID_SIZE) != 0)
+ return -1;
+
+ if (fread(&offset_to_index, sizeof(uint32_t), 1, mar->fp) != 1)
+ return -1;
+ offset_to_index = ntohl(offset_to_index);
+
+ if (fseek(mar->fp, offset_to_index, SEEK_SET))
+ return -1;
+ if (fread(&size_of_index, sizeof(uint32_t), 1, mar->fp) != 1)
+ return -1;
+ size_of_index = ntohl(size_of_index);
+
+ buf = (char *) malloc(size_of_index);
+ if (!buf)
+ return -1;
+ if (fread(buf, size_of_index, 1, mar->fp) != 1) {
+ free(buf);
+ return -1;
+ }
+
+ bufptr = buf;
+ bufend = buf + size_of_index;
+ while (bufptr < bufend && mar_consume_index(mar, &bufptr, bufend) == 0);
+
+ free(buf);
+ return (bufptr == bufend) ? 0 : -1;
+}
+
+/**
+ * Internal shared code for mar_open and mar_wopen.
+ * On failure, will fclose(fp).
+ */
+static MarFile *mar_fpopen(FILE *fp)
+{
+ MarFile *mar;
+
+ mar = (MarFile *) malloc(sizeof(*mar));
+ if (!mar) {
+ fclose(fp);
+ return NULL;
+ }
+
+ mar->fp = fp;
+ memset(mar->item_table, 0, sizeof(mar->item_table));
+ if (mar_read_index(mar)) {
+ mar_close(mar);
+ return NULL;
+ }
+
+ return mar;
+}
+
+MarFile *mar_open(const char *path) {
+ FILE *fp;
+
+ fp = fopen(path, "rb");
+ if (!fp) {
+ fprintf(stderr, "ERROR: could not open file in mar_open()\n");
+ perror(path);
+ return NULL;
+ }
+
+ return mar_fpopen(fp);
+}
+
+#ifdef XP_WIN
+MarFile *mar_wopen(const wchar_t *path) {
+ FILE *fp;
+
+ _wfopen_s(&fp, path, L"rb");
+ if (!fp) {
+ fprintf(stderr, "ERROR: could not open file in mar_wopen()\n");
+ _wperror(path);
+ return NULL;
+ }
+
+ return mar_fpopen(fp);
+}
+#endif
+
+void mar_close(MarFile *mar) {
+ MarItem *item;
+ int i;
+
+ fclose(mar->fp);
+
+ for (i = 0; i < TABLESIZE; ++i) {
+ item = mar->item_table[i];
+ while (item) {
+ MarItem *temp = item;
+ item = item->next;
+ free(temp);
+ }
+ }
+
+ free(mar);
+}
+
+/**
+ * Determines the MAR file information.
+ *
+ * @param fp An opened MAR file in read mode.
+ * @param hasSignatureBlock Optional out parameter specifying if the MAR
+ * file has a signature block or not.
+ * @param numSignatures Optional out parameter for storing the number
+ * of signatures in the MAR file.
+ * @param hasAdditionalBlocks Optional out parameter specifying if the MAR
+ * file has additional blocks or not.
+ * @param offsetAdditionalBlocks Optional out parameter for the offset to the
+ * first additional block. Value is only valid if
+ * hasAdditionalBlocks is not equal to 0.
+ * @param numAdditionalBlocks Optional out parameter for the number of
+ * additional blocks. Value is only valid if
+ * hasAdditionalBlocks is not equal to 0.
+ * @return 0 on success and non-zero on failure.
+ */
+int get_mar_file_info_fp(FILE *fp,
+ int *hasSignatureBlock,
+ uint32_t *numSignatures,
+ int *hasAdditionalBlocks,
+ uint32_t *offsetAdditionalBlocks,
+ uint32_t *numAdditionalBlocks)
+{
+ uint32_t offsetToIndex, offsetToContent, signatureCount, signatureLen, i;
+
+ /* One of hasSignatureBlock or hasAdditionalBlocks must be non NULL */
+ if (!hasSignatureBlock && !hasAdditionalBlocks) {
+ return -1;
+ }
+
+
+ /* Skip to the start of the offset index */
+ if (fseek(fp, MAR_ID_SIZE, SEEK_SET)) {
+ return -1;
+ }
+
+ /* Read the offset to the index. */
+ if (fread(&offsetToIndex, sizeof(offsetToIndex), 1, fp) != 1) {
+ return -1;
+ }
+ offsetToIndex = ntohl(offsetToIndex);
+
+ if (numSignatures) {
+ /* Skip past the MAR file size field */
+ if (fseek(fp, sizeof(uint64_t), SEEK_CUR)) {
+ return -1;
+ }
+
+ /* Read the number of signatures field */
+ if (fread(numSignatures, sizeof(*numSignatures), 1, fp) != 1) {
+ return -1;
+ }
+ *numSignatures = ntohl(*numSignatures);
+ }
+
+ /* Skip to the first index entry past the index size field
+ We do it in 2 calls because offsetToIndex + sizeof(uint32_t)
+ could oerflow in theory. */
+ if (fseek(fp, offsetToIndex, SEEK_SET)) {
+ return -1;
+ }
+
+ if (fseek(fp, sizeof(uint32_t), SEEK_CUR)) {
+ return -1;
+ }
+
+ /* Read the first offset to content field. */
+ if (fread(&offsetToContent, sizeof(offsetToContent), 1, fp) != 1) {
+ return -1;
+ }
+ offsetToContent = ntohl(offsetToContent);
+
+ /* Check if we have a new or old MAR file */
+ if (hasSignatureBlock) {
+ if (offsetToContent == MAR_ID_SIZE + sizeof(uint32_t)) {
+ *hasSignatureBlock = 0;
+ } else {
+ *hasSignatureBlock = 1;
+ }
+ }
+
+ /* If the caller doesn't care about the product info block
+ value, then just return */
+ if (!hasAdditionalBlocks) {
+ return 0;
+ }
+
+ /* Skip to the start of the signature block */
+ if (fseeko(fp, SIGNATURE_BLOCK_OFFSET, SEEK_SET)) {
+ return -1;
+ }
+
+ /* Get the number of signatures */
+ if (fread(&signatureCount, sizeof(signatureCount), 1, fp) != 1) {
+ return -1;
+ }
+ signatureCount = ntohl(signatureCount);
+
+ /* Check that we have less than the max amount of signatures so we don't
+ waste too much of either updater's or signmar's time. */
+ if (signatureCount > MAX_SIGNATURES) {
+ return -1;
+ }
+
+ /* Skip past the whole signature block */
+ for (i = 0; i < signatureCount; i++) {
+ /* Skip past the signature algorithm ID */
+ if (fseek(fp, sizeof(uint32_t), SEEK_CUR)) {
+ return -1;
+ }
+
+ /* Read the signature length and skip past the signature */
+ if (fread(&signatureLen, sizeof(uint32_t), 1, fp) != 1) {
+ return -1;
+ }
+ signatureLen = ntohl(signatureLen);
+ if (fseek(fp, signatureLen, SEEK_CUR)) {
+ return -1;
+ }
+ }
+
+ if ((int64_t)ftell(fp) == (int64_t)offsetToContent) {
+ *hasAdditionalBlocks = 0;
+ } else {
+ if (numAdditionalBlocks) {
+ /* We have an additional block, so read in the number of additional blocks
+ and set the offset. */
+ *hasAdditionalBlocks = 1;
+ if (fread(numAdditionalBlocks, sizeof(uint32_t), 1, fp) != 1) {
+ return -1;
+ }
+ *numAdditionalBlocks = ntohl(*numAdditionalBlocks);
+ if (offsetAdditionalBlocks) {
+ *offsetAdditionalBlocks = ftell(fp);
+ }
+ } else if (offsetAdditionalBlocks) {
+ /* numAdditionalBlocks is not specified but offsetAdditionalBlocks
+ is, so fill it! */
+ *offsetAdditionalBlocks = ftell(fp) + sizeof(uint32_t);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * Reads the product info block from the MAR file's additional block section.
+ * The caller is responsible for freeing the fields in infoBlock
+ * if the return is successful.
+ *
+ * @param infoBlock Out parameter for where to store the result to
+ * @return 0 on success, -1 on failure
+*/
+int
+read_product_info_block(char *path,
+ struct ProductInformationBlock *infoBlock)
+{
+ int rv;
+ MarFile mar;
+ mar.fp = fopen(path, "rb");
+ if (!mar.fp) {
+ fprintf(stderr, "ERROR: could not open file in read_product_info_block()\n");
+ perror(path);
+ return -1;
+ }
+ rv = mar_read_product_info_block(&mar, infoBlock);
+ fclose(mar.fp);
+ return rv;
+}
+
+/**
+ * Reads the product info block from the MAR file's additional block section.
+ * The caller is responsible for freeing the fields in infoBlock
+ * if the return is successful.
+ *
+ * @param infoBlock Out parameter for where to store the result to
+ * @return 0 on success, -1 on failure
+*/
+int
+mar_read_product_info_block(MarFile *mar,
+ struct ProductInformationBlock *infoBlock)
+{
+ uint32_t i, offsetAdditionalBlocks, numAdditionalBlocks,
+ additionalBlockSize, additionalBlockID;
+ int hasAdditionalBlocks;
+
+ /* The buffer size is 97 bytes because the MAR channel name < 64 bytes, and
+ product version < 32 bytes + 3 NULL terminator bytes. */
+ char buf[97] = { '\0' };
+ if (get_mar_file_info_fp(mar->fp, NULL, NULL,
+ &hasAdditionalBlocks,
+ &offsetAdditionalBlocks,
+ &numAdditionalBlocks) != 0) {
+ return -1;
+ }
+ for (i = 0; i < numAdditionalBlocks; ++i) {
+ /* Read the additional block size */
+ if (fread(&additionalBlockSize,
+ sizeof(additionalBlockSize),
+ 1, mar->fp) != 1) {
+ return -1;
+ }
+ additionalBlockSize = ntohl(additionalBlockSize) -
+ sizeof(additionalBlockSize) -
+ sizeof(additionalBlockID);
+
+ /* Read the additional block ID */
+ if (fread(&additionalBlockID,
+ sizeof(additionalBlockID),
+ 1, mar->fp) != 1) {
+ return -1;
+ }
+ additionalBlockID = ntohl(additionalBlockID);
+
+ if (PRODUCT_INFO_BLOCK_ID == additionalBlockID) {
+ const char *location;
+ int len;
+
+ /* This block must be at most 104 bytes.
+ MAR channel name < 64 bytes, and product version < 32 bytes + 3 NULL
+ terminator bytes. We only check for 96 though because we remove 8
+ bytes above from the additionalBlockSize: We subtract
+ sizeof(additionalBlockSize) and sizeof(additionalBlockID) */
+ if (additionalBlockSize > 96) {
+ return -1;
+ }
+
+ if (fread(buf, additionalBlockSize, 1, mar->fp) != 1) {
+ return -1;
+ }
+
+ /* Extract the MAR channel name from the buffer. For now we
+ point to the stack allocated buffer but we strdup this
+ if we are within bounds of each field's max length. */
+ location = buf;
+ len = strlen(location);
+ infoBlock->MARChannelID = location;
+ location += len + 1;
+ if (len >= 64) {
+ infoBlock->MARChannelID = NULL;
+ return -1;
+ }
+
+ /* Extract the version from the buffer */
+ len = strlen(location);
+ infoBlock->productVersion = location;
+ location += len + 1;
+ if (len >= 32) {
+ infoBlock->MARChannelID = NULL;
+ infoBlock->productVersion = NULL;
+ return -1;
+ }
+ infoBlock->MARChannelID =
+ strdup(infoBlock->MARChannelID);
+ infoBlock->productVersion =
+ strdup(infoBlock->productVersion);
+ return 0;
+ } else {
+ /* This is not the additional block you're looking for. Move along. */
+ if (fseek(mar->fp, additionalBlockSize, SEEK_CUR)) {
+ return -1;
+ }
+ }
+ }
+
+ /* If we had a product info block we would have already returned */
+ return -1;
+}
+
+const MarItem *mar_find_item(MarFile *mar, const char *name) {
+ uint32_t hash;
+ const MarItem *item;
+
+ hash = mar_hash_name(name);
+
+ item = mar->item_table[hash];
+ while (item && strcmp(item->name, name) != 0)
+ item = item->next;
+
+ return item;
+}
+
+int mar_enum_items(MarFile *mar, MarItemCallback callback, void *closure) {
+ MarItem *item;
+ int i;
+
+ for (i = 0; i < TABLESIZE; ++i) {
+ item = mar->item_table[i];
+ while (item) {
+ int rv = callback(mar, item, closure);
+ if (rv)
+ return rv;
+ item = item->next;
+ }
+ }
+
+ return 0;
+}
+
+int mar_read(MarFile *mar, const MarItem *item, int offset, char *buf,
+ int bufsize) {
+ int nr;
+
+ if (offset == (int) item->length)
+ return 0;
+ if (offset > (int) item->length)
+ return -1;
+
+ nr = item->length - offset;
+ if (nr > bufsize)
+ nr = bufsize;
+
+ if (fseek(mar->fp, item->offset + offset, SEEK_SET))
+ return -1;
+
+ return fread(buf, 1, nr, mar->fp);
+}
+
+/**
+ * Determines the MAR file information.
+ *
+ * @param path The path of the MAR file to check.
+ * @param hasSignatureBlock Optional out parameter specifying if the MAR
+ * file has a signature block or not.
+ * @param numSignatures Optional out parameter for storing the number
+ * of signatures in the MAR file.
+ * @param hasAdditionalBlocks Optional out parameter specifying if the MAR
+ * file has additional blocks or not.
+ * @param offsetAdditionalBlocks Optional out parameter for the offset to the
+ * first additional block. Value is only valid if
+ * hasAdditionalBlocks is not equal to 0.
+ * @param numAdditionalBlocks Optional out parameter for the number of
+ * additional blocks. Value is only valid if
+ * has_additional_blocks is not equal to 0.
+ * @return 0 on success and non-zero on failure.
+ */
+int get_mar_file_info(const char *path,
+ int *hasSignatureBlock,
+ uint32_t *numSignatures,
+ int *hasAdditionalBlocks,
+ uint32_t *offsetAdditionalBlocks,
+ uint32_t *numAdditionalBlocks)
+{
+ int rv;
+ FILE *fp = fopen(path, "rb");
+ if (!fp) {
+ fprintf(stderr, "ERROR: could not open file in get_mar_file_info()\n");
+ perror(path);
+ return -1;
+ }
+
+ rv = get_mar_file_info_fp(fp, hasSignatureBlock,
+ numSignatures, hasAdditionalBlocks,
+ offsetAdditionalBlocks, numAdditionalBlocks);
+
+ fclose(fp);
+ return rv;
+}