Projects: Include libsodium (#1051)

Add libsodium fuzzers.

Add secret_key_auth_fuzzer and secretbox_easy_fuzzer targets from libsodium.

projects/libsodium/Dockerfile

@@ -0,0 +1,22 @@
+# Copyright 2018 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+
+FROM gcr.io/oss-fuzz-base/base-builder
+MAINTAINER chriswwolfe@gmail.com
+RUN apt-get update && apt-get install -y make
+RUN git clone --depth 1 https://github.com/jedisct1/libsodium.git --branch stable libsodium
+WORKDIR libsodium
+COPY build.sh *.cc *.h $SRC/

projects/libsodium/build.sh

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+#!/bin/bash -eu
+# Copyright 2018 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+
+# build project
+./configure --prefix="$WORK" --disable-shared --enable-static LDFLAGS="$CXXFLAGS"
+make -j$(nproc) all
+
+# build fuzzers
+for f in $SRC/*_fuzzer.cc; do
+    fuzzer=$(basename "$f" _fuzzer.cc)
+    $CXX $CXXFLAGS -std=c++11 -I"$WORK/include" \
+         "$f" -o "$OUT/${fuzzer}_fuzzer" \
+         "$WORK/lib/libsodium.a" -lFuzzingEngine
+done

projects/libsodium/fake_random.h

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+#ifndef FAKE_RANDOM_H_
+#define FAKE_RANDOM_H_
+
+#include <sodium.h>
+#include <assert.h>
+#include <stdint.h>
+#include <string.h>
+#include <algorithm>
+
+static const unsigned char * SEED_DATA;
+static size_t SEED_SIZE;
+
+static const char *
+fake_implementation_name(void) {
+  return "fake_random";
+}
+
+static void
+fake_random_buffer(void * const buf, const size_t size) {
+  static unsigned char seed[randombytes_SEEDBYTES];
+  memset(seed, '0', randombytes_SEEDBYTES);
+
+  size_t boundary = std::min((size_t) randombytes_SEEDBYTES, SEED_SIZE);
+  memcpy(&seed, SEED_DATA, boundary);
+
+  randombytes_buf_deterministic(buf, size, seed);
+}
+
+struct randombytes_implementation fake_random = {
+  .implementation_name = fake_implementation_name,
+  .random = NULL,
+  .stir = NULL,
+  .uniform = NULL,
+  .buf = fake_random_buffer,
+  .close = NULL
+};
+
+void
+setup_fake_random(const unsigned char * seed, const size_t seed_size) {
+  SEED_DATA = seed;
+  SEED_SIZE = seed_size;
+
+  int fake_random_set = randombytes_set_implementation(&fake_random);
+  assert(fake_random_set == 0);
+
+  assert(randombytes_implementation_name() == "fake_random");
+  int initialized = sodium_init();
+  assert(initialized >= 0);
+}
+
+#endif // FAKE_RANDOM_H_

projects/libsodium/project.yaml

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+homepage: "https://libsodium.org"
+primary_contact: "ossfuzzz+sodium@gmail.com"
+auto_ccs:
+ - "chriswwolfe@gmail.com"

projects/libsodium/secret_key_auth_fuzzer.cc

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+#include <assert.h>
+#include <sodium.h>
+
+#include "fake_random.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const unsigned char *data, size_t size) {
+  int initialized = sodium_init();
+  assert(initialized >= 0);
+
+  setup_fake_random(data, size);
+
+  unsigned char key[crypto_auth_KEYBYTES];
+  unsigned char mac[crypto_auth_BYTES];
+
+  // this uses a deterministic generator
+  crypto_auth_keygen(key);
+
+  crypto_auth(mac, data, size, key);
+  crypto_auth_verify(mac, data, size, key);
+  return 0;
+}

projects/libsodium/secretbox_easy_fuzzer.cc

@@ -0,0 +1,28 @@
+#include <assert.h>
+#include <sodium.h>
+
+#include "fake_random.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const unsigned char *data, size_t size) {
+  int initialized = sodium_init();
+  assert(initialized >= 0);
+
+  setup_fake_random(data, size);
+
+  unsigned char key[crypto_secretbox_KEYBYTES];
+  unsigned char nonce[crypto_secretbox_NONCEBYTES];
+
+  // these use a deterministic generator
+  crypto_secretbox_keygen(key);
+  randombytes_buf(nonce, sizeof nonce);
+
+  size_t ciphertext_len = crypto_secretbox_MACBYTES + size;
+  unsigned char ciphertext[ciphertext_len];
+
+  crypto_secretbox_easy(ciphertext, data, size, nonce, key);
+
+  unsigned char decrypted[size];
+  crypto_secretbox_open_easy(decrypted, ciphertext, ciphertext_len, nonce, key);
+
+  return 0;
+}