diff options
| -rw-r--r-- | src/codec/SkRawCodec.cpp | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/src/codec/SkRawCodec.cpp b/src/codec/SkRawCodec.cpp index 609b0aef02..208bd8952d 100644 --- a/src/codec/SkRawCodec.cpp +++ b/src/codec/SkRawCodec.cpp @@ -215,6 +215,8 @@ public: } private: + // Most of valid RAW images will not be larger than 100MB. This limit is helpful to avoid + // streaming too large data chunk. We can always adjust the limit here if we need. const size_t kMaxStreamSize = 100 * 1024 * 1024; // 100MB typedef SkDynamicMemoryWStream INHERITED; @@ -445,6 +447,10 @@ public: */ static SkDngImage* NewFromStream(SkRawStream* stream) { SkAutoTDelete<SkDngImage> dngImage(new SkDngImage(stream)); + if (!dngImage->isTiffHeaderValid()) { + return nullptr; + } + if (!dngImage->initFromPiex()) { if (!dngImage->readDng()) { return nullptr; @@ -522,6 +528,20 @@ public: } private: + // Quick check if the image contains a valid TIFF header as requested by DNG format. + bool isTiffHeaderValid() const { + const size_t kHeaderSize = 4; + SkAutoSTMalloc<kHeaderSize, unsigned char> header(kHeaderSize); + if (!fStream->read(header.get(), 0 /* offset */, kHeaderSize)) { + return false; + } + + // Check if the header is valid (endian info and magic number "42"). + return + (header[0] == 0x49 && header[1] == 0x49 && header[2] == 0x2A && header[3] == 0x00) || + (header[0] == 0x4D && header[1] == 0x4D && header[2] == 0x00 && header[3] == 0x2A); + } + void init(const int width, const int height, const dng_point& cfaPatternSize) { fImageInfo = SkImageInfo::Make(width, height, kN32_SkColorType, kOpaque_SkAlphaType); |