Add decoder fuzz target.

tests/opus_decode_fuzzer.c

+/* Copyright (c) 2017 Google Inc. */
+/*
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include "opus.h"
+#include "opus_types.h"
+
+#define MAX_FRAME_SAMP 5760
+#define MAX_PACKET 1500
+
+/* 4 bytes: packet length, 4 bytes: encoder final range */
+#define SETUP_BYTE_COUNT 8
+
+typedef struct {
+    int fs;
+    int channels;
+} TocInfo;
+
+static void ParseToc(const uint8_t *toc, TocInfo *const info) {
+    const int samp_freqs[5] = {8000, 12000, 16000, 24000, 48000};
+    const int bandwidth = opus_packet_get_bandwidth(toc);
+
+    info->fs = samp_freqs[bandwidth - OPUS_BANDWIDTH_NARROWBAND];
+    info->channels = opus_packet_get_nb_channels(toc);
+}
+
+/* Treats the input data as concatenated packets encoded by opus_demo,
+ * structured as
+ *    bytes 0..3: packet length
+ *    bytes 4..7: encoder final range
+ *    bytes 8+  : Opus packet, including ToC
+ */
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+    OpusDecoder *dec;
+    opus_int16 *pcm;
+    uint8_t *packet;
+    TocInfo toc;
+    int i, err;
+
+    /* Not enough data to setup the decoder (+1 for the ToC) */
+    if (size < SETUP_BYTE_COUNT + 1) {
+        return 0;
+    }
+
+    /* Create decoder based on info from the first ToC available */
+    ParseToc(&data[SETUP_BYTE_COUNT], &toc);
+
+    dec = opus_decoder_create(toc.fs, toc.channels, &err);
+    if (err != OPUS_OK | dec == NULL) {
+        return 0;
+    }
+
+    pcm = (opus_int16*) malloc(sizeof(*pcm) * MAX_FRAME_SAMP * toc.channels);
+    packet = (uint8_t*) calloc(MAX_PACKET, sizeof(*packet));
+
+    i = 0;
+    while (1) {
+        int len, fec;
+
+        if (i + SETUP_BYTE_COUNT >= size) {
+            break;
+        }
+
+        len = (opus_uint32) data[i    ] << 24 |
+              (opus_uint32) data[i + 1] << 16 |
+              (opus_uint32) data[i + 2] <<  8 |
+              (opus_uint32) data[i + 3];
+        if (len > MAX_PACKET || len < 0) {
+            break;
+        }
+
+        /* Bytes 4..7 represent encoder final range, but are unused here.
+         * Instead, byte 4 is repurposed to determine if FEC is used. */
+        fec = data[i + 4] & 1;
+
+        /* Lost packet */
+        if (len == 0) {
+            int frame_size;
+            opus_decoder_ctl(dec, OPUS_GET_LAST_PACKET_DURATION(&frame_size));
+            (void) opus_decode(dec, NULL, size, pcm, frame_size, fec);
+        } else {
+            if (i + SETUP_BYTE_COUNT + len > size) {
+                break;
+            }
+            memcpy(pcm, &data[i + SETUP_BYTE_COUNT], len);
+            (void) opus_decode(dec, data, size, pcm, MAX_FRAME_SAMP, fec);
+        }
+
+        i += SETUP_BYTE_COUNT + len;
+    }
+
+    opus_decoder_destroy(dec);
+    free(pcm);
+    free(packet);
+
+    return 0;
+}

tests/opus_decode_fuzzer.options

+[libfuzzer]
+max_len = 1000000