Update web-platform-tests to revision 157b71e48394fb63f91fa497be429c3543b0ab03

tests/wpt/web-platform-tests/compression/decompression-corrupt-input.any.js

@@ -0,0 +1,299 @@
+// META global=worker
+
+// This test checks that DecompressionStream behaves according to the standard
+// when the input is corrupted. To avoid a combinatorial explosion in the
+// number of tests, we only mutate one field at a time, and we only test
+// "interesting" values.
+
+'use strict';
+
+// The many different cases are summarised in this data structure.
+const expectations = [
+  {
+    format: 'deflate',
+
+    // Decompresses to 'expected output'.
+    baseInput: [120, 156, 75, 173, 40, 72, 77, 46, 73, 77, 81, 200, 47, 45, 41,
+                40, 45, 1, 0, 48, 173, 6, 36],
+
+    // See RFC1950 for the definition of the various fields used by deflate:
+    // https://tools.ietf.org/html/rfc1950.
+    fields: [
+      {
+        // The function of this field. This matches the name used in the RFC.
+        name: 'CMF',
+
+        // The offset of the field in bytes from the start of the input.
+        offset: 0,
+
+        // The length of the field in bytes.
+        length: 1,
+
+        cases: [
+          {
+            // The value to set the field to. If the field contains multiple
+            // bytes, all the bytes will be set to this value.
+            value: 0,
+
+            // The expected result. 'success' means the input is decoded
+            // successfully. 'error' means that the stream will be errored.
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'FLG',
+        offset: 1,
+        length: 1,
+
+        // FLG contains a 4-bit checksum (FCHECK) which is calculated in such a
+        // way that there are 4 valid values for this field.
+        cases: [
+          {
+            value: 218,
+            result: 'success'
+          },
+          {
+            value: 1,
+            result: 'success'
+          },
+          {
+            value: 94,
+            result: 'success'
+          },
+          {
+            // The remaining 252 values cause an error.
+            value: 157,
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'DATA',
+        // In general, changing any bit of the data will trigger a checksum
+        // error. Only the last byte does anything else.
+        offset: 18,
+        length: 1,
+        cases: [
+          {
+            value: 4,
+            result: 'success'
+          },
+          {
+            value: 5,
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'ADLER',
+        offset: -4,
+        length: 4,
+        cases: [
+          {
+            value: 255,
+            result: 'error'
+          }
+        ]
+      }
+    ]
+  },
+  {
+    format: 'gzip',
+
+    // Decompresses to 'expected output'.
+    baseInput: [31, 139, 8, 0, 0, 0, 0, 0, 0, 3, 75, 173, 40, 72, 77, 46, 73,
+                77, 81, 200, 47, 45, 41, 40, 45, 1, 0, 176, 1, 57, 179, 15, 0,
+                0, 0],
+
+    // See RFC1952 for the definition of the various fields used by gzip:
+    // https://tools.ietf.org/html/rfc1952.
+    fields: [
+      {
+        name: 'ID',
+        offset: 0,
+        length: 2,
+        cases: [
+          {
+            value: 255,
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'CM',
+        offset: 2,
+        length: 1,
+        cases: [
+          {
+            value: 0,
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'FLG',
+        offset: 3,
+        length: 1,
+        cases: [
+          {
+            value: 1, // FTEXT
+            result: 'success'
+          },
+          {
+            value: 2, // FHCRC
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'MTIME',
+        offset: 4,
+        length: 4,
+        cases: [
+          {
+            // Any value is valid for this field.
+            value: 255,
+            result: 'success'
+          }
+        ]
+      },
+      {
+        name: 'XFL',
+        offset: 8,
+        length: 1,
+        cases: [
+          {
+            // Any value is accepted.
+            value: 255,
+            result: 'success'
+          }
+        ]
+      },
+      {
+        name: 'OS',
+        offset: 9,
+        length: 1,
+        cases: [
+          {
+            // Any value is accepted.
+            value: 128,
+            result: 'success'
+          }
+        ]
+      },
+      {
+        name: 'DATA',
+
+        // The last byte of the data is the most interesting.
+        offset: 26,
+        length: 1,
+        cases: [
+          {
+            value: 3,
+            result: 'error'
+          },
+          {
+            value: 4,
+            result: 'success'
+          }
+        ]
+      },
+      {
+        name: 'CRC',
+        offset: -8,
+        length: 4,
+        cases: [
+          {
+            // Any change will error the stream.
+            value: 0,
+            result: 'error'
+          }
+        ]
+      },
+      {
+        name: 'ISIZE',
+        offset: -4,
+        length: 4,
+        cases: [
+          {
+            // A mismatch will error the stream.
+            value: 1,
+            result: 'error'
+          }
+        ]
+      }
+    ]
+  }
+];
+
+async function tryDecompress(input, format) {
+  const ds = new DecompressionStream(format);
+  const reader = ds.readable.getReader();
+  const writer = ds.writable.getWriter();
+  writer.write(input).catch(() => {});
+  writer.close().catch(() => {});
+  let out = [];
+  while (true) {
+    try {
+      const { value, done } = await reader.read();
+      if (done) {
+        break;
+      }
+      out = out.concat(Array.from(value));
+    } catch (e) {
+      return { result: 'error' };
+    }
+  }
+  const expectedOutput = 'expected output';
+  if (out.length !== expectedOutput.length) {
+    return { result: 'corrupt' };
+  }
+  for (let i = 0; i < out.length; ++i) {
+    if (out[i] !== expectedOutput.charCodeAt(i)) {
+      return { result: 'corrupt' };
+    }
+  }
+  return { result: 'success' };
+}
+
+function corruptInput(input, offset, length, value) {
+  const output = new Uint8Array(input);
+  if (offset < 0) {
+    offset += input.length;
+  }
+  for (let i = offset; i < offset + length; ++i) {
+    output[i] = value;
+  }
+  return output;
+}
+
+for (const { format, baseInput, fields } of expectations) {
+  promise_test(async () => {
+    const { result } = await tryDecompress(new Uint8Array(baseInput), format);
+    assert_equals(result, 'success', 'decompression should succeed');
+  }, `the unchanged input for '${format}' should decompress successfully`);
+
+  promise_test(async () => {
+    const truncatedInput = new Uint8Array(baseInput.slice(0, -1));
+    const { result } = await tryDecompress(truncatedInput, format);
+    assert_equals(result, 'error', 'decompression should fail');
+  }, `truncating the input for '${format}' should give an error`);
+
+  promise_test(async () => {
+    const extendedInput = new Uint8Array(baseInput.concat([0]));
+    const { result } = await tryDecompress(extendedInput, format);
+    assert_equals(result, 'error', 'decompression should fail');
+  }, `trailing junk for '${format}' should give an error`);
+
+  for (const { name, offset, length, cases } of fields) {
+    for (const { value, result } of cases) {
+      promise_test(async () => {
+        const corruptedInput = corruptInput(baseInput, offset, length, value);
+        const { result: actual } =
+              await tryDecompress(corruptedInput, format);
+        assert_equals(actual, result, 'result should match');
+      }, `format '${format}' field ${name} should be ${result} for ${value}`);
+    }
+  }
+}