pineapple-src/src/core/hle/service/ssl/ssl_backend_schannel.cpp

545 lines
23 KiB
C++
Executable File

// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include <mutex>
#include "common/error.h"
#include "common/fs/file.h"
#include "common/hex_util.h"
#include "common/string_util.h"
#include "core/hle/service/ssl/ssl_backend.h"
#include "core/internal_network/network.h"
#include "core/internal_network/sockets.h"
namespace {
// These includes are inside the namespace to avoid a conflict on MinGW where
// the headers define an enum containing Network and Service as enumerators
// (which clash with the correspondingly named namespaces).
#define SECURITY_WIN32
#include <schnlsp.h>
#include <security.h>
#include <wincrypt.h>
std::once_flag one_time_init_flag;
bool one_time_init_success = false;
SCHANNEL_CRED schannel_cred{};
CredHandle cred_handle;
static void OneTimeInit() {
schannel_cred.dwVersion = SCHANNEL_CRED_VERSION;
schannel_cred.dwFlags =
SCH_USE_STRONG_CRYPTO | // don't allow insecure protocols
SCH_CRED_AUTO_CRED_VALIDATION | // validate certs
SCH_CRED_NO_DEFAULT_CREDS; // don't automatically present a client certificate
// ^ I'm assuming that nobody would want to connect Yuzu to a
// service that requires some OS-provided corporate client
// certificate, and presenting one to some arbitrary server
// might be a privacy concern? Who knows, though.
const SECURITY_STATUS ret =
AcquireCredentialsHandle(nullptr, const_cast<LPTSTR>(UNISP_NAME), SECPKG_CRED_OUTBOUND,
nullptr, &schannel_cred, nullptr, nullptr, &cred_handle, nullptr);
if (ret != SEC_E_OK) {
// SECURITY_STATUS codes are a type of HRESULT and can be used with NativeErrorToString.
LOG_ERROR(Service_SSL, "AcquireCredentialsHandle failed: {}",
Common::NativeErrorToString(ret));
return;
}
if (getenv("SSLKEYLOGFILE")) {
LOG_CRITICAL(Service_SSL, "SSLKEYLOGFILE was set but Schannel does not support exporting "
"keys; not logging keys!");
// Not fatal.
}
one_time_init_success = true;
}
} // namespace
namespace Service::SSL {
class SSLConnectionBackendSchannel final : public SSLConnectionBackend {
public:
Result Init() {
std::call_once(one_time_init_flag, OneTimeInit);
if (!one_time_init_success) {
LOG_ERROR(
Service_SSL,
"Can't create SSL connection because Schannel one-time initialization failed");
return ResultInternalError;
}
return ResultSuccess;
}
void SetSocket(std::shared_ptr<Network::SocketBase> socket_in) override {
socket = std::move(socket_in);
}
Result SetHostName(const std::string& hostname_in) override {
hostname = hostname_in;
return ResultSuccess;
}
Result DoHandshake() override {
while (1) {
Result r;
switch (handshake_state) {
case HandshakeState::Initial:
if ((r = FlushCiphertextWriteBuf()) != ResultSuccess ||
(r = CallInitializeSecurityContext()) != ResultSuccess) {
return r;
}
// CallInitializeSecurityContext updated `handshake_state`.
continue;
case HandshakeState::ContinueNeeded:
case HandshakeState::IncompleteMessage:
if ((r = FlushCiphertextWriteBuf()) != ResultSuccess ||
(r = FillCiphertextReadBuf()) != ResultSuccess) {
return r;
}
if (ciphertext_read_buf.empty()) {
LOG_ERROR(Service_SSL, "SSL handshake failed because server hung up");
return ResultInternalError;
}
if ((r = CallInitializeSecurityContext()) != ResultSuccess) {
return r;
}
// CallInitializeSecurityContext updated `handshake_state`.
continue;
case HandshakeState::DoneAfterFlush:
if ((r = FlushCiphertextWriteBuf()) != ResultSuccess) {
return r;
}
handshake_state = HandshakeState::Connected;
return ResultSuccess;
case HandshakeState::Connected:
LOG_ERROR(Service_SSL, "Called DoHandshake but we already handshook");
return ResultInternalError;
case HandshakeState::Error:
return ResultInternalError;
}
}
}
Result FillCiphertextReadBuf() {
const size_t fill_size = read_buf_fill_size ? read_buf_fill_size : 4096;
read_buf_fill_size = 0;
// This unnecessarily zeroes the buffer; oh well.
const size_t offset = ciphertext_read_buf.size();
ASSERT_OR_EXECUTE(offset + fill_size >= offset, { return ResultInternalError; });
ciphertext_read_buf.resize(offset + fill_size, 0);
const auto read_span = std::span(ciphertext_read_buf).subspan(offset, fill_size);
const auto [actual, err] = socket->Recv(0, read_span);
switch (err) {
case Network::Errno::SUCCESS:
ASSERT(static_cast<size_t>(actual) <= fill_size);
ciphertext_read_buf.resize(offset + actual);
return ResultSuccess;
case Network::Errno::AGAIN:
ciphertext_read_buf.resize(offset);
return ResultWouldBlock;
default:
ciphertext_read_buf.resize(offset);
LOG_ERROR(Service_SSL, "Socket recv returned Network::Errno {}", err);
return ResultInternalError;
}
}
// Returns success if the write buffer has been completely emptied.
Result FlushCiphertextWriteBuf() {
while (!ciphertext_write_buf.empty()) {
const auto [actual, err] = socket->Send(ciphertext_write_buf, 0);
switch (err) {
case Network::Errno::SUCCESS:
ASSERT(static_cast<size_t>(actual) <= ciphertext_write_buf.size());
ciphertext_write_buf.erase(ciphertext_write_buf.begin(),
ciphertext_write_buf.begin() + actual);
break;
case Network::Errno::AGAIN:
return ResultWouldBlock;
default:
LOG_ERROR(Service_SSL, "Socket send returned Network::Errno {}", err);
return ResultInternalError;
}
}
return ResultSuccess;
}
Result CallInitializeSecurityContext() {
const unsigned long req = ISC_REQ_ALLOCATE_MEMORY | ISC_REQ_CONFIDENTIALITY |
ISC_REQ_INTEGRITY | ISC_REQ_REPLAY_DETECT |
ISC_REQ_SEQUENCE_DETECT | ISC_REQ_STREAM |
ISC_REQ_USE_SUPPLIED_CREDS;
unsigned long attr;
// https://learn.microsoft.com/en-us/windows/win32/secauthn/initializesecuritycontext--schannel
std::array<SecBuffer, 2> input_buffers{{
// only used if `initial_call_done`
{
// [0]
.cbBuffer = static_cast<unsigned long>(ciphertext_read_buf.size()),
.BufferType = SECBUFFER_TOKEN,
.pvBuffer = ciphertext_read_buf.data(),
},
{
// [1] (will be replaced by SECBUFFER_MISSING when SEC_E_INCOMPLETE_MESSAGE is
// returned, or SECBUFFER_EXTRA when SEC_E_CONTINUE_NEEDED is returned if the
// whole buffer wasn't used)
.cbBuffer = 0,
.BufferType = SECBUFFER_EMPTY,
.pvBuffer = nullptr,
},
}};
std::array<SecBuffer, 2> output_buffers{{
{
.cbBuffer = 0,
.BufferType = SECBUFFER_TOKEN,
.pvBuffer = nullptr,
}, // [0]
{
.cbBuffer = 0,
.BufferType = SECBUFFER_ALERT,
.pvBuffer = nullptr,
}, // [1]
}};
SecBufferDesc input_desc{
.ulVersion = SECBUFFER_VERSION,
.cBuffers = static_cast<unsigned long>(input_buffers.size()),
.pBuffers = input_buffers.data(),
};
SecBufferDesc output_desc{
.ulVersion = SECBUFFER_VERSION,
.cBuffers = static_cast<unsigned long>(output_buffers.size()),
.pBuffers = output_buffers.data(),
};
ASSERT_OR_EXECUTE_MSG(
input_buffers[0].cbBuffer == ciphertext_read_buf.size(),
{ return ResultInternalError; }, "read buffer too large");
bool initial_call_done = handshake_state != HandshakeState::Initial;
if (initial_call_done) {
LOG_DEBUG(Service_SSL, "Passing {} bytes into InitializeSecurityContext",
ciphertext_read_buf.size());
}
const SECURITY_STATUS ret =
InitializeSecurityContextA(&cred_handle, initial_call_done ? &ctxt : nullptr,
// Caller ensured we have set a hostname:
const_cast<char*>(hostname.value().c_str()), req,
0, // Reserved1
0, // TargetDataRep not used with Schannel
initial_call_done ? &input_desc : nullptr,
0, // Reserved2
initial_call_done ? nullptr : &ctxt, &output_desc, &attr,
nullptr); // ptsExpiry
if (output_buffers[0].pvBuffer) {
const std::span span(static_cast<u8*>(output_buffers[0].pvBuffer),
output_buffers[0].cbBuffer);
ciphertext_write_buf.insert(ciphertext_write_buf.end(), span.begin(), span.end());
FreeContextBuffer(output_buffers[0].pvBuffer);
}
if (output_buffers[1].pvBuffer) {
const std::span span(static_cast<u8*>(output_buffers[1].pvBuffer),
output_buffers[1].cbBuffer);
// The documentation doesn't explain what format this data is in.
LOG_DEBUG(Service_SSL, "Got a {}-byte alert buffer: {}", span.size(),
Common::HexToString(span));
}
switch (ret) {
case SEC_I_CONTINUE_NEEDED:
LOG_DEBUG(Service_SSL, "InitializeSecurityContext => SEC_I_CONTINUE_NEEDED");
if (input_buffers[1].BufferType == SECBUFFER_EXTRA) {
LOG_DEBUG(Service_SSL, "EXTRA of size {}", input_buffers[1].cbBuffer);
ASSERT(input_buffers[1].cbBuffer <= ciphertext_read_buf.size());
ciphertext_read_buf.erase(ciphertext_read_buf.begin(),
ciphertext_read_buf.end() - input_buffers[1].cbBuffer);
} else {
ASSERT(input_buffers[1].BufferType == SECBUFFER_EMPTY);
ciphertext_read_buf.clear();
}
handshake_state = HandshakeState::ContinueNeeded;
return ResultSuccess;
case SEC_E_INCOMPLETE_MESSAGE:
LOG_DEBUG(Service_SSL, "InitializeSecurityContext => SEC_E_INCOMPLETE_MESSAGE");
ASSERT(input_buffers[1].BufferType == SECBUFFER_MISSING);
read_buf_fill_size = input_buffers[1].cbBuffer;
handshake_state = HandshakeState::IncompleteMessage;
return ResultSuccess;
case SEC_E_OK:
LOG_DEBUG(Service_SSL, "InitializeSecurityContext => SEC_E_OK");
ciphertext_read_buf.clear();
handshake_state = HandshakeState::DoneAfterFlush;
return GrabStreamSizes();
default:
LOG_ERROR(Service_SSL,
"InitializeSecurityContext failed (probably certificate/protocol issue): {}",
Common::NativeErrorToString(ret));
handshake_state = HandshakeState::Error;
return ResultInternalError;
}
}
Result GrabStreamSizes() {
const SECURITY_STATUS ret =
QueryContextAttributes(&ctxt, SECPKG_ATTR_STREAM_SIZES, &stream_sizes);
if (ret != SEC_E_OK) {
LOG_ERROR(Service_SSL, "QueryContextAttributes(SECPKG_ATTR_STREAM_SIZES) failed: {}",
Common::NativeErrorToString(ret));
handshake_state = HandshakeState::Error;
return ResultInternalError;
}
return ResultSuccess;
}
ResultVal<size_t> Read(std::span<u8> data) override {
if (handshake_state != HandshakeState::Connected) {
LOG_ERROR(Service_SSL, "Called Read but we did not successfully handshake");
return ResultInternalError;
}
if (data.size() == 0 || got_read_eof) {
return size_t(0);
}
while (1) {
if (!cleartext_read_buf.empty()) {
const size_t read_size = std::min(cleartext_read_buf.size(), data.size());
std::memcpy(data.data(), cleartext_read_buf.data(), read_size);
cleartext_read_buf.erase(cleartext_read_buf.begin(),
cleartext_read_buf.begin() + read_size);
return read_size;
}
if (!ciphertext_read_buf.empty()) {
SecBuffer empty{
.cbBuffer = 0,
.BufferType = SECBUFFER_EMPTY,
.pvBuffer = nullptr,
};
std::array<SecBuffer, 5> buffers{{
{
.cbBuffer = static_cast<unsigned long>(ciphertext_read_buf.size()),
.BufferType = SECBUFFER_DATA,
.pvBuffer = ciphertext_read_buf.data(),
},
empty,
empty,
empty,
}};
ASSERT_OR_EXECUTE_MSG(
buffers[0].cbBuffer == ciphertext_read_buf.size(),
{ return ResultInternalError; }, "read buffer too large");
SecBufferDesc desc{
.ulVersion = SECBUFFER_VERSION,
.cBuffers = static_cast<unsigned long>(buffers.size()),
.pBuffers = buffers.data(),
};
SECURITY_STATUS ret =
DecryptMessage(&ctxt, &desc, /*MessageSeqNo*/ 0, /*pfQOP*/ nullptr);
switch (ret) {
case SEC_E_OK:
ASSERT_OR_EXECUTE(buffers[0].BufferType == SECBUFFER_STREAM_HEADER,
{ return ResultInternalError; });
ASSERT_OR_EXECUTE(buffers[1].BufferType == SECBUFFER_DATA,
{ return ResultInternalError; });
ASSERT_OR_EXECUTE(buffers[2].BufferType == SECBUFFER_STREAM_TRAILER,
{ return ResultInternalError; });
cleartext_read_buf.assign(static_cast<u8*>(buffers[1].pvBuffer),
static_cast<u8*>(buffers[1].pvBuffer) +
buffers[1].cbBuffer);
if (buffers[3].BufferType == SECBUFFER_EXTRA) {
ASSERT(buffers[3].cbBuffer <= ciphertext_read_buf.size());
ciphertext_read_buf.erase(ciphertext_read_buf.begin(),
ciphertext_read_buf.end() - buffers[3].cbBuffer);
} else {
ASSERT(buffers[3].BufferType == SECBUFFER_EMPTY);
ciphertext_read_buf.clear();
}
continue;
case SEC_E_INCOMPLETE_MESSAGE:
break;
case SEC_I_CONTEXT_EXPIRED:
// Server hung up by sending close_notify.
got_read_eof = true;
return size_t(0);
default:
LOG_ERROR(Service_SSL, "DecryptMessage failed: {}",
Common::NativeErrorToString(ret));
return ResultInternalError;
}
}
const Result r = FillCiphertextReadBuf();
if (r != ResultSuccess) {
return r;
}
if (ciphertext_read_buf.empty()) {
got_read_eof = true;
return size_t(0);
}
}
}
ResultVal<size_t> Write(std::span<const u8> data) override {
if (handshake_state != HandshakeState::Connected) {
LOG_ERROR(Service_SSL, "Called Write but we did not successfully handshake");
return ResultInternalError;
}
if (data.size() == 0) {
return size_t(0);
}
data = data.subspan(0, std::min<size_t>(data.size(), stream_sizes.cbMaximumMessage));
if (!cleartext_write_buf.empty()) {
// Already in the middle of a write. It wouldn't make sense to not
// finish sending the entire buffer since TLS has
// header/MAC/padding/etc.
if (data.size() != cleartext_write_buf.size() ||
std::memcmp(data.data(), cleartext_write_buf.data(), data.size())) {
LOG_ERROR(Service_SSL, "Called Write but buffer does not match previous buffer");
return ResultInternalError;
}
return WriteAlreadyEncryptedData();
} else {
cleartext_write_buf.assign(data.begin(), data.end());
}
std::vector<u8> header_buf(stream_sizes.cbHeader, 0);
std::vector<u8> tmp_data_buf = cleartext_write_buf;
std::vector<u8> trailer_buf(stream_sizes.cbTrailer, 0);
std::array<SecBuffer, 3> buffers{{
{
.cbBuffer = stream_sizes.cbHeader,
.BufferType = SECBUFFER_STREAM_HEADER,
.pvBuffer = header_buf.data(),
},
{
.cbBuffer = static_cast<unsigned long>(tmp_data_buf.size()),
.BufferType = SECBUFFER_DATA,
.pvBuffer = tmp_data_buf.data(),
},
{
.cbBuffer = stream_sizes.cbTrailer,
.BufferType = SECBUFFER_STREAM_TRAILER,
.pvBuffer = trailer_buf.data(),
},
}};
ASSERT_OR_EXECUTE_MSG(
buffers[1].cbBuffer == tmp_data_buf.size(), { return ResultInternalError; },
"temp buffer too large");
SecBufferDesc desc{
.ulVersion = SECBUFFER_VERSION,
.cBuffers = static_cast<unsigned long>(buffers.size()),
.pBuffers = buffers.data(),
};
const SECURITY_STATUS ret = EncryptMessage(&ctxt, /*fQOP*/ 0, &desc, /*MessageSeqNo*/ 0);
if (ret != SEC_E_OK) {
LOG_ERROR(Service_SSL, "EncryptMessage failed: {}", Common::NativeErrorToString(ret));
return ResultInternalError;
}
ciphertext_write_buf.insert(ciphertext_write_buf.end(), header_buf.begin(),
header_buf.end());
ciphertext_write_buf.insert(ciphertext_write_buf.end(), tmp_data_buf.begin(),
tmp_data_buf.end());
ciphertext_write_buf.insert(ciphertext_write_buf.end(), trailer_buf.begin(),
trailer_buf.end());
return WriteAlreadyEncryptedData();
}
ResultVal<size_t> WriteAlreadyEncryptedData() {
const Result r = FlushCiphertextWriteBuf();
if (r != ResultSuccess) {
return r;
}
// write buf is empty
const size_t cleartext_bytes_written = cleartext_write_buf.size();
cleartext_write_buf.clear();
return cleartext_bytes_written;
}
ResultVal<std::vector<std::vector<u8>>> GetServerCerts() override {
PCCERT_CONTEXT returned_cert = nullptr;
const SECURITY_STATUS ret =
QueryContextAttributes(&ctxt, SECPKG_ATTR_REMOTE_CERT_CONTEXT, &returned_cert);
if (ret != SEC_E_OK) {
LOG_ERROR(Service_SSL,
"QueryContextAttributes(SECPKG_ATTR_REMOTE_CERT_CONTEXT) failed: {}",
Common::NativeErrorToString(ret));
return ResultInternalError;
}
PCCERT_CONTEXT some_cert = nullptr;
std::vector<std::vector<u8>> certs;
while ((some_cert = CertEnumCertificatesInStore(returned_cert->hCertStore, some_cert))) {
certs.emplace_back(static_cast<u8*>(some_cert->pbCertEncoded),
static_cast<u8*>(some_cert->pbCertEncoded) +
some_cert->cbCertEncoded);
}
std::reverse(certs.begin(),
certs.end()); // Windows returns certs in reverse order from what we want
CertFreeCertificateContext(returned_cert);
return certs;
}
~SSLConnectionBackendSchannel() {
if (handshake_state != HandshakeState::Initial) {
DeleteSecurityContext(&ctxt);
}
}
enum class HandshakeState {
// Haven't called anything yet.
Initial,
// `SEC_I_CONTINUE_NEEDED` was returned by
// `InitializeSecurityContext`; must finish sending data (if any) in
// the write buffer, then read at least one byte before calling
// `InitializeSecurityContext` again.
ContinueNeeded,
// `SEC_E_INCOMPLETE_MESSAGE` was returned by
// `InitializeSecurityContext`; hopefully the write buffer is empty;
// must read at least one byte before calling
// `InitializeSecurityContext` again.
IncompleteMessage,
// `SEC_E_OK` was returned by `InitializeSecurityContext`; must
// finish sending data in the write buffer before having `DoHandshake`
// report success.
DoneAfterFlush,
// We finished the above and are now connected. At this point, writing
// and reading are separate 'state machines' represented by the
// nonemptiness of the ciphertext and cleartext read and write buffers.
Connected,
// Another error was returned and we shouldn't allow initialization
// to continue.
Error,
} handshake_state = HandshakeState::Initial;
CtxtHandle ctxt;
SecPkgContext_StreamSizes stream_sizes;
std::shared_ptr<Network::SocketBase> socket;
std::optional<std::string> hostname;
std::vector<u8> ciphertext_read_buf;
std::vector<u8> ciphertext_write_buf;
std::vector<u8> cleartext_read_buf;
std::vector<u8> cleartext_write_buf;
bool got_read_eof = false;
size_t read_buf_fill_size = 0;
};
ResultVal<std::unique_ptr<SSLConnectionBackend>> CreateSSLConnectionBackend() {
auto conn = std::make_unique<SSLConnectionBackendSchannel>();
const Result res = conn->Init();
if (res.IsFailure()) {
return res;
}
return conn;
}
} // namespace Service::SSL