Test BMP files more thoroughly to be sure they're valid.
This is work-in-progress. More tests to come...
Change-Id: Id2e59fd7d0229be3ad90b29b2d0dc035ceeca666
BUG=chromium-os:11766
TEST=manual
Adding an example to the test framework. Use
make
make runbmptests
to ensure it works.
Review URL: http://codereview.chromium.org/6286157
diff --git a/utility/bmpblk_utility.cc b/utility/bmpblk_utility.cc
index a87761c..750235c 100644
--- a/utility/bmpblk_utility.cc
+++ b/utility/bmpblk_utility.cc
@@ -16,10 +16,28 @@
#include <string.h>
#include <yaml.h>
-/* The offsets of width and height fields in a BMP file.
- * See http://en.wikipedia.org/wiki/BMP_file_format */
-#define BMP_WIDTH_OFFSET 18
-#define BMP_HEIGHT_OFFSET 22
+/* BMP header, used to validate image requirements
+ * See http://en.wikipedia.org/wiki/BMP_file_format
+ */
+typedef struct {
+ uint8_t CharB; // must be 'B'
+ uint8_t CharM; // must be 'M'
+ uint32_t Size;
+ uint16_t Reserved[2];
+ uint32_t ImageOffset;
+ uint32_t HeaderSize;
+ uint32_t PixelWidth;
+ uint32_t PixelHeight;
+ uint16_t Planes; // Must be 1 for x86
+ uint16_t BitPerPixel; // 1, 4, 8, or 24 for x86
+ uint32_t CompressionType; // must be 0 for x86
+ uint32_t ImageSize;
+ uint32_t XPixelsPerMeter;
+ uint32_t YPixelsPerMeter;
+ uint32_t NumberOfColors;
+ uint32_t ImportantColors;
+} __attribute__((packed)) BMP_IMAGE_HEADER;
+
static void error(const char *format, ...) {
va_list ap;
@@ -132,9 +150,14 @@
if (event.type != YAML_SCALAR_EVENT) {
error("Syntax error in parsing bmpblock.\n");
}
- config_.header.major_version = atoi((char*)event.data.scalar.value);
- config_.header.minor_version = atoi(
- strchr((char*)event.data.scalar.value, '.') + 1);
+ char wantversion[20];
+ sprintf(wantversion, "%d.%d",
+ BMPBLOCK_MAJOR_VERSION,
+ BMPBLOCK_MINOR_VERSION);
+ string gotversion = (char*)event.data.scalar.value;
+ if (gotversion != wantversion) {
+ error("Invalid version specified in config file\n");
+ }
yaml_event_delete(&event);
}
@@ -305,29 +328,32 @@
}
ImageFormat BmpBlockUtil::get_image_format(const string content) {
- if (content[0] == 'B' && content[1] == 'M')
- return FORMAT_BMP;
- else
+ if (content.size() < sizeof(BMP_IMAGE_HEADER))
return FORMAT_INVALID;
+ const BMP_IMAGE_HEADER *hdr = (const BMP_IMAGE_HEADER *)content.c_str();
+
+ if (hdr->CharB != 'B' || hdr->CharM != 'M' ||
+ hdr->Planes != 1 ||
+ hdr->CompressionType != 0 ||
+ (hdr->BitPerPixel != 1 && hdr->BitPerPixel != 4 &&
+ hdr->BitPerPixel != 8 && hdr->BitPerPixel != 24))
+ return FORMAT_INVALID;
+
+ return FORMAT_BMP;
}
uint32_t BmpBlockUtil::get_bmp_image_width(const string content) {
- const char *start = content.c_str();
- uint32_t width = *(uint32_t*)(start + BMP_WIDTH_OFFSET);
- /* Do a rough verification. */
- assert(width > 0 && width < 1600);
- return width;
+ const BMP_IMAGE_HEADER *hdr = (const BMP_IMAGE_HEADER *)content.c_str();
+ return hdr->PixelWidth;
}
uint32_t BmpBlockUtil::get_bmp_image_height(const string content) {
- const char *start = content.c_str();
- uint32_t height = *(uint32_t*)(start + BMP_HEIGHT_OFFSET);
- /* Do a rough verification. */
- assert(height > 0 && height < 1000);
- return height;
+ const BMP_IMAGE_HEADER *hdr = (const BMP_IMAGE_HEADER *)content.c_str();
+ return hdr->PixelHeight;
}
void BmpBlockUtil::fill_all_image_infos() {
+ int errcnt = 0;
for (StrImageConfigMap::iterator it = config_.images_map.begin();
it != config_.images_map.end();
++it) {
@@ -338,9 +364,13 @@
it->second.data.height = get_bmp_image_height(it->second.raw_content);
break;
default:
- error("Unsupported image format.\n");
+ fprintf(stderr, "Unsupported image format in %s\n",
+ it->second.filename.c_str());
+ errcnt++;
}
}
+ if (errcnt)
+ error("Unable to continue due to errors.\n");
}
void BmpBlockUtil::compress_all_images(const Compression compress) {
@@ -363,6 +393,8 @@
memset(&config_.header, '\0', sizeof(config_.header));
memcpy(&config_.header.signature, BMPBLOCK_SIGNATURE,
BMPBLOCK_SIGNATURE_SIZE);
+ config_.header.major_version = BMPBLOCK_MAJOR_VERSION;
+ config_.header.minor_version = BMPBLOCK_MINOR_VERSION;
config_.header.number_of_localizations = config_.localizations.size();
config_.header.number_of_screenlayouts = config_.localizations[0].size();
for (unsigned int i = 1; i < config_.localizations.size(); ++i) {