ES: Implement VerifySign

This implements ES_VerifySign which is notably used by the system menu
when importing saves.

Now *all* ES commands that are actually used by titles are implemented.

Source/Core/Core/IOS/ES/ES.cpp

@@ -524,6 +524,8 @@ IPCCommandResult ES::IOCtlV(const IOCtlVRequest& request)
     return GetDeviceCertificate(request);
   case IOCTL_ES_SIGN:
     return Sign(request);
+  case IOCTL_ES_VERIFYSIGN:
+    return VerifySign(request);
   case IOCTL_ES_GETBOOT2VERSION:
     return GetBoot2Version(request);
 
@@ -539,7 +541,6 @@ IPCCommandResult ES::IOCtlV(const IOCtlVRequest& request)
   case IOCTL_ES_DELETE_STREAM_KEY:
     return DeleteStreamKey(request);
 
-  case IOCTL_ES_VERIFYSIGN:
   case IOCTL_ES_UNKNOWN_41:
   case IOCTL_ES_UNKNOWN_42:
     PanicAlert("IOS-ES: Unimplemented ioctlv 0x%x (%zu in vectors, %zu io vectors)",

Source/Core/Core/IOS/ES/ES.h

@@ -132,6 +132,9 @@ public:
   ReturnCode GetDeviceId(u32* device_id) const;
   ReturnCode GetTitleId(u64* device_id) const;
 
+  ReturnCode VerifySign(const std::vector<u8>& hash, const std::vector<u8>& ecc_signature,
+                        const std::vector<u8>& certs);
+
   // Views
   ReturnCode GetV0TicketFromView(const u8* ticket_view, u8* ticket) const;
   ReturnCode GetTicketFromView(const u8* ticket_view, u8* ticket, u32* ticket_size) const;
@@ -243,6 +246,7 @@ private:
   IPCCommandResult GetDeviceCertificate(const IOCtlVRequest& request);
   IPCCommandResult CheckKoreaRegion(const IOCtlVRequest& request);
   IPCCommandResult Sign(const IOCtlVRequest& request);
+  IPCCommandResult VerifySign(const IOCtlVRequest& request);
   IPCCommandResult Encrypt(u32 uid, const IOCtlVRequest& request);
   IPCCommandResult Decrypt(u32 uid, const IOCtlVRequest& request);
 

Source/Core/Core/IOS/ES/Identity.cpp

@@ -4,10 +4,14 @@
 
 #include "Core/IOS/ES/ES.h"
 
-#include <cstring>
 #include <vector>
 
+#include <mbedtls/sha1.h>
+
 #include "Common/Logging/Log.h"
+#include "Common/ScopeGuard.h"
+#include "Common/StringUtil.h"
+#include "Core/ConfigManager.h"
 #include "Core/HW/Memmap.h"
 #include "Core/IOS/ES/Formats.h"
 #include "Core/IOS/Uids.h"
@@ -114,6 +118,99 @@ IPCCommandResult ES::Sign(const IOCtlVRequest& request)
   m_ios.GetIOSC().Sign(sig_out, ap_cert_out, m_title_context.tmd.GetTitleId(), data, data_size);
   return GetDefaultReply(IPC_SUCCESS);
 }
+
+ReturnCode ES::VerifySign(const std::vector<u8>& hash, const std::vector<u8>& ecc_signature,
+                          const std::vector<u8>& certs_bytes)
+{
+  if (!SConfig::GetInstance().m_enable_signature_checks)
+  {
+    WARN_LOG(IOS_ES, "VerifySign: signature checks are disabled. Skipping.");
+    return IPC_SUCCESS;
+  }
+
+  const std::map<std::string, IOS::ES::CertReader> certs = IOS::ES::ParseCertChain(certs_bytes);
+  if (certs.empty())
+    return ES_EINVAL;
+
+  const auto ap_iterator = std::find_if(certs.begin(), certs.end(), [](const auto& entry) {
+    return entry.first.length() > 2 && entry.first.compare(0, 2, "AP") == 0;
+  });
+  if (ap_iterator == certs.end())
+    return ES_UNKNOWN_ISSUER;
+  const IOS::ES::CertReader& ap = ap_iterator->second;
+
+  const auto ap_issuers = SplitString(ap.GetIssuer(), '-');
+  const auto ng_iterator = ap_issuers.size() > 1 ? certs.find(*ap_issuers.rbegin()) : certs.end();
+  if (ng_iterator == certs.end())
+    return ES_UNKNOWN_ISSUER;
+  const IOS::ES::CertReader& ng = ng_iterator->second;
+
+  IOSC& iosc = m_ios.GetIOSC();
+  IOSC::Handle ng_cert;
+  ReturnCode ret = iosc.CreateObject(&ng_cert, IOSC::TYPE_PUBLIC_KEY, IOSC::SUBTYPE_ECC233, PID_ES);
+  if (ret != IPC_SUCCESS)
+    return ret;
+  Common::ScopeGuard handle_guard{[&] { iosc.DeleteObject(ng_cert, PID_ES); }};
+
+  ret = VerifyContainer(VerifyContainerType::Device, VerifyMode::DoNotUpdateCertStore, ng,
+                        certs_bytes, ng_cert);
+  if (ret != IPC_SUCCESS)
+  {
+    ERROR_LOG(IOS_ES, "VerifySign: VerifyContainer(ng) failed with error %d", ret);
+    return ret;
+  }
+
+  ret = iosc.VerifyPublicKeySign(ap.GetSha1(), ng_cert, ap.GetSignatureData(), PID_ES);
+  if (ret != IPC_SUCCESS)
+  {
+    ERROR_LOG(IOS_ES, "VerifySign: IOSC_VerifyPublicKeySign(ap) failed with error %d", ret);
+    return ret;
+  }
+
+  IOSC::Handle ap_cert;
+  ret = iosc.CreateObject(&ap_cert, IOSC::TYPE_PUBLIC_KEY, IOSC::SUBTYPE_ECC233, PID_ES);
+  if (ret != IPC_SUCCESS)
+    return ret;
+  Common::ScopeGuard handle2_guard{[&] { iosc.DeleteObject(ap_cert, PID_ES); }};
+
+  ret = iosc.ImportPublicKey(ap_cert, ap.GetPublicKey().data(), nullptr, PID_ES);
+  if (ret != IPC_SUCCESS)
+  {
+    ERROR_LOG(IOS_ES, "VerifySign: IOSC_ImportPublicKey(ap) failed with error %d", ret);
+    return ret;
+  }
+
+  std::array<u8, 20> sha1;
+  mbedtls_sha1(hash.data(), hash.size(), sha1.data());
+  ret = iosc.VerifyPublicKeySign(sha1, ap_cert, ecc_signature, PID_ES);
+  if (ret != IPC_SUCCESS)
+  {
+    ERROR_LOG(IOS_ES, "VerifySign: IOSC_VerifyPublicKeySign(data) failed with error %d", ret);
+    return ret;
+  }
+
+  INFO_LOG(IOS_ES, "VerifySign: all checks passed");
+  return IPC_SUCCESS;
+}
+
+IPCCommandResult ES::VerifySign(const IOCtlVRequest& request)
+{
+  if (!request.HasNumberOfValidVectors(3, 0))
+    return GetDefaultReply(ES_EINVAL);
+  if (request.in_vectors[1].size != sizeof(IOS::ECCSignature))
+    return GetDefaultReply(ES_EINVAL);
+
+  std::vector<u8> hash(request.in_vectors[0].size);
+  Memory::CopyFromEmu(hash.data(), request.in_vectors[0].address, hash.size());
+
+  std::vector<u8> ecc_signature(request.in_vectors[1].size);
+  Memory::CopyFromEmu(ecc_signature.data(), request.in_vectors[1].address, ecc_signature.size());
+
+  std::vector<u8> certs(request.in_vectors[2].size);
+  Memory::CopyFromEmu(certs.data(), request.in_vectors[2].address, certs.size());
+
+  return GetDefaultReply(VerifySign(hash, ecc_signature, certs));
+}
 }  // namespace Device
 }  // namespace HLE
 }  // namespace IOS