1 files changed, 121 insertions, 0 deletions
diff --git a/payload_consumer/certificate_parser_android.cc b/payload_consumer/certificate_parser_android.cc
new file mode 100644
index 00000000..4a20547a
--- /dev/null
+++ b/payload_consumer/certificate_parser_android.cc
@@ -0,0 +1,121 @@
+//
+// Copyright (C) 2019 The Android Open Source Project
+//
+// 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.
+//
+
+#include "update_engine/payload_consumer/certificate_parser_android.h"
+
+#include <memory>
+#include <utility>
+
+#include <base/logging.h>
+#include <openssl/bio.h>
+#include <openssl/pem.h>
+#include <ziparchive/zip_archive.h>
+
+#include "update_engine/payload_consumer/certificate_parser_interface.h"
+
+namespace {
+bool IterateZipEntriesAndSearchForKeys(
+    const ZipArchiveHandle& handle, std::vector<std::vector<uint8_t>>* result) {
+  void* cookie;
+  int32_t iter_status = StartIteration(handle, &cookie, "", "x509.pem");
+  if (iter_status != 0) {
+    LOG(ERROR) << "Failed to iterate over entries in the certificate zipfile: "
+               << ErrorCodeString(iter_status);
+    return false;
+  }
+  std::unique_ptr<void, decltype(&EndIteration)> guard(cookie, EndIteration);
+
+  std::vector<std::vector<uint8_t>> pem_keys;
+  std::string_view name;
+  ZipEntry entry;
+  while ((iter_status = Next(cookie, &entry, &name)) == 0) {
+    std::vector<uint8_t> pem_content(entry.uncompressed_length);
+    if (int32_t extract_status = ExtractToMemory(
+            handle, &entry, pem_content.data(), pem_content.size());
+        extract_status != 0) {
+      LOG(ERROR) << "Failed to extract " << name << ": "
+                 << ErrorCodeString(extract_status);
+      return false;
+    }
+    pem_keys.push_back(pem_content);
+  }
+
+  if (iter_status != -1) {
+    LOG(ERROR) << "Error while iterating over zip entries: "
+               << ErrorCodeString(iter_status);
+    return false;
+  }
+
+  *result = std::move(pem_keys);
+  return true;
+}
+
+}  // namespace
+
+namespace chromeos_update_engine {
+bool CertificateParserAndroid::ReadPublicKeysFromCertificates(
+    const std::string& path,
+    std::vector<std::unique_ptr<EVP_PKEY, decltype(&EVP_PKEY_free)>>*
+        out_public_keys) {
+  out_public_keys->clear();
+
+  ZipArchiveHandle handle;
+  if (int32_t open_status = OpenArchive(path.c_str(), &handle);
+      open_status != 0) {
+    LOG(ERROR) << "Failed to open " << path << ": "
+               << ErrorCodeString(open_status);
+    return false;
+  }
+
+  std::vector<std::vector<uint8_t>> pem_certs;
+  if (!IterateZipEntriesAndSearchForKeys(handle, &pem_certs)) {
+    CloseArchive(handle);
+    return false;
+  }
+  CloseArchive(handle);
+
+  // Convert the certificates into public keys. Stop and return false if we
+  // encounter an error.
+  std::vector<std::unique_ptr<EVP_PKEY, decltype(&EVP_PKEY_free)>> result;
+  for (const auto& cert : pem_certs) {
+    std::unique_ptr<BIO, decltype(&BIO_free)> input(
+        BIO_new_mem_buf(cert.data(), cert.size()), BIO_free);
+
+    std::unique_ptr<X509, decltype(&X509_free)> x509(
+        PEM_read_bio_X509(input.get(), nullptr, nullptr, nullptr), X509_free);
+    if (!x509) {
+      LOG(ERROR) << "Failed to read x509 certificate";
+      return false;
+    }
+
+    std::unique_ptr<EVP_PKEY, decltype(&EVP_PKEY_free)> public_key(
+        X509_get_pubkey(x509.get()), EVP_PKEY_free);
+    if (!public_key) {
+      LOG(ERROR) << "Failed to extract the public key from x509 certificate";
+      return false;
+    }
+    result.push_back(std::move(public_key));
+  }
+
+  *out_public_keys = std::move(result);
+  return true;
+}
+
+std::unique_ptr<CertificateParserInterface> CreateCertificateParser() {
+  return std::make_unique<CertificateParserAndroid>();
+}
+
+}  // namespace chromeos_update_engine