commit 22af5afe1eb68315841eb4031fce9a8f2c9034dd
author Fredrik Söderquist <fs@opera.com> Sat Sep 29 00:38:43 2018
committer Commit Bot <commit-bot@chromium.org> Sat Sep 29 00:38:43 2018
tree 347d462b6dcc6255f1f0bbec2c9228f9bca40d99
parent 20153791d53f7be390d659763ac794cad405edda

Fix WebP sniff pattern

The current pattern wouldn't be able to sniff the 'lossless' and
'extended' WebP formats.

Adjust the pattern to match the one described by [1].

[1] https://mimesniff.spec.whatwg.org/#matching-an-image-type-pattern

Bug: 889420
Change-Id: I4b5a73d4d9477502d58df7460b9494e6540a59f3
Reviewed-on: https://chromium-review.googlesource.com/1248782
Reviewed-by: Asanka Herath <asanka@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#595273}

net/base/mime_sniffer.cc

diff --git a/net/base/mime_sniffer.cc b/net/base/mime_sniffer.cc
index 3f60f22..ace836a5 100644
--- a/net/base/mime_sniffer.cc
+++ b/net/base/mime_sniffer.cc
@@ -152,7 +152,7 @@
   MAGIC_NUMBER("image/tiff", "II*"),
   MAGIC_NUMBER("image/tiff", "MM\x00*"),
   MAGIC_NUMBER("audio/mpeg", "ID3"),
-  MAGIC_NUMBER("image/webp", "RIFF....WEBPVP8 "),
+  MAGIC_NUMBER("image/webp", "RIFF....WEBPVP"),
   MAGIC_NUMBER("video/webm", "\x1A\x45\xDF\xA3"),
   MAGIC_NUMBER("application/zip", "PK\x03\x04"),
   MAGIC_NUMBER("application/x-rar-compressed", "Rar!\x1A\x07\x00"),

net/base/mime_sniffer_unittest.cc

diff --git a/net/base/mime_sniffer_unittest.cc b/net/base/mime_sniffer_unittest.cc
index 5c200eb6..dd417c7 100644
--- a/net/base/mime_sniffer_unittest.cc
+++ b/net/base/mime_sniffer_unittest.cc
@@ -458,6 +458,27 @@
   mime_type.clear();
 }
 
+TEST(MimeSnifferTest, ImageTest) {
+  std::string mime_type;
+  const char kWebPSimpleFormat[] = "RIFF\xee\x81\x00\x00WEBPVP8 ";
+  EXPECT_TRUE(SniffMimeTypeFromLocalData(
+      kWebPSimpleFormat, sizeof(kWebPSimpleFormat) - 1, &mime_type));
+  EXPECT_EQ("image/webp", mime_type);
+  mime_type.clear();
+
+  const char kWebPLosslessFormat[] = "RIFF\xee\x81\x00\x00WEBPVP8L";
+  EXPECT_TRUE(SniffMimeTypeFromLocalData(
+      kWebPLosslessFormat, sizeof(kWebPLosslessFormat) - 1, &mime_type));
+  EXPECT_EQ("image/webp", mime_type);
+  mime_type.clear();
+
+  const char kWebPExtendedFormat[] = "RIFF\xee\x81\x00\x00WEBPVP8X";
+  EXPECT_TRUE(SniffMimeTypeFromLocalData(
+      kWebPExtendedFormat, sizeof(kWebPExtendedFormat) - 1, &mime_type));
+  EXPECT_EQ("image/webp", mime_type);
+  mime_type.clear();
+}
+
 // The tests need char parameters, but the ranges to test include 0xFF, and some
 // platforms have signed chars and are noisy about it. Using an int parameter
 // and casting it to char inside the test case solves both these problems.