// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "chrome/browser/extensions/api/platform_keys/verify_trust_api.h"
#include <algorithm>
#include <memory>
#include <optional>
#include <string_view>
#include <utility>
#include "base/containers/contains.h"
#include "base/functional/bind.h"
#include "base/functional/callback_helpers.h"
#include "base/lazy_instance.h"
#include "base/memory/ref_counted.h"
#include "chrome/browser/extensions/api/platform_keys/platform_keys_api.h"
#include "chrome/common/extensions/api/platform_keys_internal.h"
#include "content/public/browser/browser_thread.h"
#include "extensions/browser/extension_registry_factory.h"
#include "net/base/net_errors.h"
#include "net/cert/cert_verifier.h"
#include "net/cert/cert_verify_result.h"
#include "net/cert/x509_certificate.h"
#include "net/log/net_log_with_source.h"
namespace extensions {
namespace {
base::LazyInstance<BrowserContextKeyedAPIFactory<VerifyTrustAPI>>::Leaky
g_verify_trust_api_factory = LAZY_INSTANCE_INITIALIZER;
const char kErrorEmptyCertificateChain[] =
"Server certificate chain must not be empty.";
} // namespace
// This class bundles IO data and functions of the VerifyTrustAPI that are to be
// used on the IO thread only.
// It is created on the UI thread and afterwards lives on the IO thread.
class VerifyTrustAPI::IOPart {
public:
~IOPart();
// Verifies the certificate as stated by |params| and calls back |callback|
// with the result (see the declaration of VerifyCallback).
// Will not call back after this object is destructed or the verifier for this
// extension is deleted (see OnExtensionUnloaded).
void Verify(std::optional<Params> params,
const std::string& extension_id,
VerifyCallback callback);
// Must be called when the extension with id |extension_id| is unloaded.
// Deletes the verifier for |extension_id| and cancels all pending
// verifications of this verifier.
void OnExtensionUnloaded(const std::string& extension_id);
private:
struct RequestState {
RequestState() {}
RequestState(const RequestState&) = delete;
RequestState& operator=(const RequestState&) = delete;
std::unique_ptr<net::CertVerifier::Request> request;
};
// Calls back |callback| with the result and no error.
void CallBackWithResult(VerifyCallback callback,
std::unique_ptr<net::CertVerifyResult> verify_result,
RequestState* request_state,
int return_value);
// One CertVerifier per extension to verify trust. Each verifier is created on
// first usage and deleted when this IOPart is destructed or the respective
// extension is unloaded.
std::map<std::string, std::unique_ptr<net::CertVerifier>>
extension_to_verifier_;
};
// static
BrowserContextKeyedAPIFactory<VerifyTrustAPI>*
VerifyTrustAPI::GetFactoryInstance() {
return g_verify_trust_api_factory.Pointer();
}
template <>
void BrowserContextKeyedAPIFactory<
VerifyTrustAPI>::DeclareFactoryDependencies() {
DependsOn(ExtensionsBrowserClient::Get()->GetExtensionSystemFactory());
DependsOn(ExtensionRegistryFactory::GetInstance());
}
VerifyTrustAPI::VerifyTrustAPI(content::BrowserContext* context)
: io_part_(new IOPart) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
registry_observation_.Observe(ExtensionRegistry::Get(context));
}
VerifyTrustAPI::~VerifyTrustAPI() {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
}
void VerifyTrustAPI::Verify(std::optional<Params> params,
const std::string& extension_id,
VerifyCallback ui_callback) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
// Call back through the VerifyTrustAPI object on the UIThread. Because of the
// WeakPtr usage, this will ensure that |ui_callback| is not called after the
// API is destroyed.
VerifyCallback finish_callback(base::BindOnce(
&CallBackOnUI,
base::BindOnce(&VerifyTrustAPI::FinishedVerificationOnUI,
weak_factory_.GetWeakPtr(), std::move(ui_callback))));
content::GetIOThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(&IOPart::Verify, base::Unretained(io_part_.get()),
std::move(params), extension_id,
std::move(finish_callback)));
}
void VerifyTrustAPI::OnExtensionUnloaded(
content::BrowserContext* browser_context,
const Extension* extension,
UnloadedExtensionReason reason) {
content::GetIOThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(&IOPart::OnExtensionUnloaded,
base::Unretained(io_part_.get()), extension->id()));
}
void VerifyTrustAPI::FinishedVerificationOnUI(VerifyCallback ui_callback,
const std::string& error,
int return_value,
int cert_status) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
std::move(ui_callback).Run(error, return_value, cert_status);
}
// static
void VerifyTrustAPI::CallBackOnUI(VerifyCallback ui_callback,
const std::string& error,
int return_value,
int cert_status) {
content::GetUIThreadTaskRunner({})->PostTask(
FROM_HERE,
base::BindOnce(std::move(ui_callback), error, return_value, cert_status));
}
VerifyTrustAPI::IOPart::~IOPart() {
DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
}
void VerifyTrustAPI::IOPart::Verify(std::optional<Params> params,
const std::string& extension_id,
VerifyCallback callback) {
DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
const api::platform_keys::VerificationDetails& details = params->details;
if (details.server_certificate_chain.empty()) {
std::move(callback).Run(kErrorEmptyCertificateChain, 0, 0);
return;
}
std::vector<std::string_view> der_cert_chain;
for (const std::vector<uint8_t>& cert_der :
details.server_certificate_chain) {
if (cert_der.empty()) {
std::move(callback).Run(platform_keys::kErrorInvalidX509Cert, 0, 0);
return;
}
der_cert_chain.push_back(std::string_view(
reinterpret_cast<const char*>(cert_der.data()), cert_der.size()));
}
scoped_refptr<net::X509Certificate> cert_chain(
net::X509Certificate::CreateFromDERCertChain(der_cert_chain));
if (!cert_chain) {
std::move(callback).Run(platform_keys::kErrorInvalidX509Cert, 0, 0);
return;
}
if (!base::Contains(extension_to_verifier_, extension_id)) {
extension_to_verifier_[extension_id] =
net::CertVerifier::CreateDefault(/*cert_net_fetcher=*/nullptr);
}
net::CertVerifier* verifier = extension_to_verifier_[extension_id].get();
std::unique_ptr<net::CertVerifyResult> verify_result(
new net::CertVerifyResult);
std::unique_ptr<net::NetLogWithSource> net_log(new net::NetLogWithSource);
const int flags = 0;
std::string ocsp_response;
std::string sct_list;
net::CertVerifyResult* const verify_result_ptr = verify_result.get();
RequestState* request_state = new RequestState();
using VerificationCallback = base::OnceCallback<void(int)>;
VerificationCallback bound_callback = base::BindOnce(
&IOPart::CallBackWithResult, base::Unretained(this), std::move(callback),
std::move(verify_result), base::Owned(request_state));
std::pair<VerificationCallback, VerificationCallback> split_callback =
base::SplitOnceCallback(std::move(bound_callback));
const int return_value = verifier->Verify(
net::CertVerifier::RequestParams(std::move(cert_chain), details.hostname,
flags, ocsp_response, sct_list),
verify_result_ptr, std::move(split_callback.first),
&request_state->request, *net_log);
if (return_value != net::ERR_IO_PENDING) {
std::move(split_callback.second).Run(return_value);
return;
}
}
void VerifyTrustAPI::IOPart::OnExtensionUnloaded(
const std::string& extension_id) {
extension_to_verifier_.erase(extension_id);
}
void VerifyTrustAPI::IOPart::CallBackWithResult(
VerifyCallback callback,
std::unique_ptr<net::CertVerifyResult> verify_result,
RequestState* request_state,
int return_value) {
DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
std::move(callback).Run(std::string() /* no error message */, return_value,
verify_result->cert_status);
}
} // namespace extensions