/*
* Zip file constants.
*/
-#define kEOCDSignature 0x06054b50
-#define kEOCDLen 22
-#define kEOCDNumEntries 8 // offset to #of entries in file
-#define kEOCDSize 12 // size of the central directory
-#define kEOCDFileOffset 16 // offset to central directory
-
-#define kMaxCommentLen 65535 // longest possible in ushort
-#define kMaxEOCDSearch (kMaxCommentLen + kEOCDLen)
-
-#define kLFHSignature 0x04034b50
-#define kLFHLen 30 // excluding variable-len fields
-#define kLFHNameLen 26 // offset to filename length
-#define kLFHExtraLen 28 // offset to extra length
-
-#define kCDESignature 0x02014b50
-#define kCDELen 46 // excluding variable-len fields
-#define kCDEMethod 10 // offset to compression method
-#define kCDEModWhen 12 // offset to modification timestamp
-#define kCDECRC 16 // offset to entry CRC
-#define kCDECompLen 20 // offset to compressed length
-#define kCDEUncompLen 24 // offset to uncompressed length
-#define kCDENameLen 28 // offset to filename length
-#define kCDEExtraLen 30 // offset to extra length
-#define kCDECommentLen 32 // offset to comment length
-#define kCDELocalOffset 42 // offset to local hdr
+#define kEOCDSignature 0x06054b50
+#define kEOCDLen 22
+#define kEOCDDiskNumber 4 // number of the current disk
+#define kEOCDDiskNumberForCD 6 // disk number with the Central Directory
+#define kEOCDNumEntries 8 // offset to #of entries in file
+#define kEOCDTotalNumEntries 10 // offset to total #of entries in spanned archives
+#define kEOCDSize 12 // size of the central directory
+#define kEOCDFileOffset 16 // offset to central directory
+#define kEOCDCommentSize 20 // offset to the length of the file comment
+
+#define kMaxCommentLen 65535 // longest possible in ushort
+#define kMaxEOCDSearch (kMaxCommentLen + kEOCDLen)
+
+#define kLFHSignature 0x04034b50
+#define kLFHLen 30 // excluding variable-len fields
+#define kLFHGPBFlags 6 // offset to GPB flags
+#define kLFHNameLen 26 // offset to filename length
+#define kLFHExtraLen 28 // offset to extra length
+
+#define kCDESignature 0x02014b50
+#define kCDELen 46 // excluding variable-len fields
+#define kCDEGPBFlags 8 // offset to GPB flags
+#define kCDEMethod 10 // offset to compression method
+#define kCDEModWhen 12 // offset to modification timestamp
+#define kCDECRC 16 // offset to entry CRC
+#define kCDECompLen 20 // offset to compressed length
+#define kCDEUncompLen 24 // offset to uncompressed length
+#define kCDENameLen 28 // offset to filename length
+#define kCDEExtraLen 30 // offset to extra length
+#define kCDECommentLen 32 // offset to comment length
+#define kCDELocalOffset 42 // offset to local hdr
+
+/* General Purpose Bit Flag */
+#define kGPFEncryptedFlag (1 << 0)
+#define kGPFUnsupportedMask (kGPFEncryptedFlag)
/*
- * The values we return for ZipEntry use 0 as an invalid value, so we
+ * The values we return for ZipEntryRO use 0 as an invalid value, so we
* want to adjust the hash table index by a fixed amount. Using a large
- * value helps insure that people don't mix & match arguments, e.g. with
- * entry indices.
+ * value helps insure that people don't mix & match arguments, e.g. to
+ * findEntryByIndex().
*/
#define kZipEntryAdj 10000
}
static int mapCentralDirectory0(int fd, const char* debugFileName,
- ZipArchive* pArchive, off_t fileLength, size_t readAmount, u1* scanBuf)
+ ZipArchive* pArchive, off64_t fileLength, size_t readAmount, u1* scanBuf)
{
- off_t searchStart = fileLength - readAmount;
+ /*
+ * Make sure this is a Zip archive.
+ */
+ if (lseek64(pArchive->mFd, 0, SEEK_SET) != 0) {
+ ALOGW("seek to start failed: %s", strerror(errno));
+ return false;
+ }
- if (lseek(fd, searchStart, SEEK_SET) != searchStart) {
- ALOGW("Zip: seek %ld failed: %s", (long) searchStart, strerror(errno));
- return -1;
+ ssize_t actual = TEMP_FAILURE_RETRY(read(pArchive->mFd, scanBuf, sizeof(int32_t)));
+ if (actual != (ssize_t) sizeof(int32_t)) {
+ ALOGI("couldn't read first signature from zip archive: %s", strerror(errno));
+ return false;
+ }
+
+ unsigned int header = get4LE(scanBuf);
+ if (header != kLFHSignature) {
+ ALOGV("Not a Zip archive (found 0x%08x)\n", header);
+ return false;
+ }
+
+ /*
+ * Perform the traditional EOCD snipe hunt.
+ *
+ * We're searching for the End of Central Directory magic number,
+ * which appears at the start of the EOCD block. It's followed by
+ * 18 bytes of EOCD stuff and up to 64KB of archive comment. We
+ * need to read the last part of the file into a buffer, dig through
+ * it to find the magic number, parse some values out, and use those
+ * to determine the extent of the CD.
+ *
+ * We start by pulling in the last part of the file.
+ */
+ off64_t searchStart = fileLength - readAmount;
+
+ if (lseek64(pArchive->mFd, searchStart, SEEK_SET) != searchStart) {
+ ALOGW("seek %ld failed: %s\n", (long) searchStart, strerror(errno));
+ return false;
}
- ssize_t actual = TEMP_FAILURE_RETRY(read(fd, scanBuf, readAmount));
+ actual = TEMP_FAILURE_RETRY(read(pArchive->mFd, scanBuf, readAmount));
if (actual != (ssize_t) readAmount) {
- ALOGW("Zip: read %zd failed: %s", readAmount, strerror(errno));
- return -1;
+ ALOGW("Zip: read %zd, expected %zd. Failed: %s\n",
+ actual, readAmount, strerror(errno));
+ return false;
}
+
/*
* Scan backward for the EOCD magic. In an archive without a trailing
* comment, we'll find it on the first try. (We may want to consider
return -1;
}
- off_t eocdOffset = searchStart + i;
+ off64_t eocdOffset = searchStart + i;
const u1* eocdPtr = scanBuf + i;
assert(eocdOffset < fileLength);
* Grab the CD offset and size, and the number of entries in the
* archive. Verify that they look reasonable.
*/
+ u4 diskNumber = get2LE(eocdPtr + kEOCDDiskNumber);
+ u4 diskWithCentralDir = get2LE(eocdPtr + kEOCDDiskNumberForCD);
u4 numEntries = get2LE(eocdPtr + kEOCDNumEntries);
- u4 dirSize = get4LE(eocdPtr + kEOCDSize);
- u4 dirOffset = get4LE(eocdPtr + kEOCDFileOffset);
-
- if ((long long) dirOffset + (long long) dirSize > (long long) eocdOffset) {
- ALOGW("Zip: bad offsets (dir %ld, size %u, eocd %ld)",
- (long) dirOffset, dirSize, (long) eocdOffset);
- return -1;
+ u4 totalNumEntries = get2LE(eocdPtr + kEOCDTotalNumEntries);
+ u4 centralDirSize = get4LE(eocdPtr + kEOCDSize);
+ u4 centralDirOffset = get4LE(eocdPtr + kEOCDFileOffset);
+ u4 commentSize = get2LE(eocdPtr + kEOCDCommentSize);
+
+ // Verify that they look reasonable.
+ if ((long long) centralDirOffset + (long long) centralDirSize > (long long) eocdOffset) {
+ ALOGW("bad offsets (dir %ld, size %u, eocd %ld)\n",
+ (long) centralDirOffset, centralDirSize, (long) eocdOffset);
+ return false;
}
if (numEntries == 0) {
- ALOGW("Zip: empty archive?");
- return -1;
+ ALOGW("empty archive?\n");
+ return false;
+ } else if (numEntries != totalNumEntries || diskNumber != 0 || diskWithCentralDir != 0) {
+ ALOGW("spanned archives not supported");
+ return false;
}
- ALOGV("+++ numEntries=%d dirSize=%d dirOffset=%d",
- numEntries, dirSize, dirOffset);
+ // Check to see if comment is a sane size
+ if (((size_t) commentSize > (fileLength - kEOCDLen))
+ || (eocdOffset > (fileLength - kEOCDLen) - commentSize)) {
+ ALOGW("comment size runs off end of file");
+ return false;
+ }
+
+ ALOGV("+++ numEntries=%d dirSize=%d dirOffset=%d\n",
+ numEntries, centralDirSize, centralDirOffset);
/*
* It all looks good. Create a mapping for the CD, and set the fields
* in pArchive.
*/
- if (sysMapFileSegmentInShmem(fd, dirOffset, dirSize,
+ if (sysMapFileSegmentInShmem(fd, centralDirOffset, centralDirSize,
&pArchive->mDirectoryMap) != 0)
{
ALOGW("Zip: cd map failed");
}
pArchive->mNumEntries = numEntries;
- pArchive->mDirectoryOffset = dirOffset;
+ pArchive->mDirectoryOffset = centralDirOffset;
return 0;
}
/*
* Get and test file length.
*/
- off_t fileLength = lseek(fd, 0, SEEK_END);
+ off64_t fileLength = lseek64(fd, 0, SEEK_END);
if (fileLength < kEOCDLen) {
ALOGV("Zip: length %ld is too small to be zip", (long) fileLength);
return -1;
goto bail;
}
- unsigned int fileNameLen, extraLen, commentLen, hash;
- fileNameLen = get2LE(ptr + kCDENameLen);
+ unsigned int gpbf = get2LE(ptr + kCDEGPBFlags);
+ if ((gpbf & kGPFUnsupportedMask) != 0) {
+ ALOGW("Invalid General Purpose Bit Flag: %d", gpbf);
+ goto bail;
+ }
+
+ unsigned int nameLen, extraLen, commentLen, hash;
+ nameLen = get2LE(ptr + kCDENameLen);
extraLen = get2LE(ptr + kCDEExtraLen);
commentLen = get2LE(ptr + kCDECommentLen);
+ const char *name = (const char *) ptr + kCDELen;
+
+ /* Check name for NULL characters */
+ if (memchr(name, 0, nameLen) != NULL) {
+ ALOGW("Filename contains NUL byte");
+ goto bail;
+ }
+
/* add the CDE filename to the hash table */
- hash = computeHash((const char*)ptr + kCDELen, fileNameLen);
- addToHash(pArchive, (const char*)ptr + kCDELen, fileNameLen, hash);
+ hash = computeHash(name, nameLen);
+ addToHash(pArchive, name, nameLen, hash);
- ptr += kCDELen + fileNameLen + extraLen + commentLen;
+ /* We don't care about the comment or extra data. */
+ ptr += kCDELen + nameLen + extraLen + commentLen;
if ((size_t)(ptr - cdPtr) > cdLength) {
ALOGW("Zip: bad CD advance (%d vs %zd) at entry %d",
(int) (ptr - cdPtr), cdLength, i);
return -1;
}
- off_t dataOffset = localHdrOffset + kLFHLen
+ u4 gpbf = get2LE(lfhBuf + kLFHGPBFlags);
+ if ((gpbf & kGPFUnsupportedMask) != 0) {
+ ALOGW("Invalid General Purpose Bit Flag: %d", gpbf);
+ return -1;
+ }
+
+ off64_t dataOffset = localHdrOffset + kLFHLen
+ get2LE(lfhBuf + kLFHNameLen) + get2LE(lfhBuf + kLFHExtraLen);
if (dataOffset >= cdOffset) {
ALOGW("Zip: bad data offset %ld in zip", (long) dataOffset);
OSDN Git Service
