Merge pull request #6914 from leoetlino/verifysign

ES: Implement VerifySign (last remaining unimplemented, actually used ioctlv)

8 files changed, 205 insertions, 63 deletions

diff --git a/Source/Core/Common/Crypto/ec.cpp b/Source/Core/Common/Crypto/ec.cpp
index 9906ccd5e9..b9a0ca6491 100644
--- a/Source/Core/Common/Crypto/ec.cpp
+++ b/Source/Core/Common/Crypto/ec.cpp
@@ -278,8 +278,10 @@ std::array<u8, 60> Sign(const u8* key, const u8* hash)
   return signature;
 }
 
-UNUSED static int check_ecdsa(u8* Q, u8* R, u8* S, const u8* hash)
+bool VerifySignature(const u8* public_key, const u8* signature, const u8* hash)
 {
+  const u8* R = signature;
+  const u8* S = signature + 30;
   u8 Sinv[30];
 
   bn_inv(Sinv, S, ec_N, 30);
@@ -290,7 +292,7 @@ UNUSED static int check_ecdsa(u8* Q, u8* R, u8* S, const u8* hash)
   bn_mul(w1, e, Sinv, ec_N, 30);
   bn_mul(w2, R, Sinv, ec_N, 30);
 
-  Point r1 = w1 * ec_G + w2 * Point{Q};
+  Point r1 = w1 * ec_G + w2 * Point{public_key};
   auto& rx = r1.X().data;
   if (bn_compare(rx.data(), ec_N, 30) >= 0)
     bn_sub_modulus(rx.data(), ec_N, 30);
diff --git a/Source/Core/Common/Crypto/ec.h b/Source/Core/Common/Crypto/ec.h
index 18b0d48d98..442bbec311 100644
--- a/Source/Core/Common/Crypto/ec.h
+++ b/Source/Core/Common/Crypto/ec.h
@@ -13,6 +13,13 @@ namespace Common::ec
 /// Generate a signature using ECDSA.
 std::array<u8, 60> Sign(const u8* key, const u8* hash);
 
+/// Check a signature using ECDSA.
+///
+/// @param  public_key  30 byte ECC public key
+/// @param  signature   60 byte signature
+/// @param  hash        Message hash
+bool VerifySignature(const u8* public_key, const u8* signature, const u8* hash);
+
 /// Compute a shared secret from a private key (30 bytes) and public key (60 bytes).
 std::array<u8, 60> ComputeSharedSecret(const u8* private_key, const u8* public_key);
 
diff --git a/Source/Core/Core/IOS/ES/ES.cpp b/Source/Core/Core/IOS/ES/ES.cpp
index e75bdfb77d..227f6d78fd 100644
--- a/Source/Core/Core/IOS/ES/ES.cpp
+++ b/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)",
diff --git a/Source/Core/Core/IOS/ES/ES.h b/Source/Core/Core/IOS/ES/ES.h
index dd1050c6e6..174d3836e7 100644
--- a/Source/Core/Core/IOS/ES/ES.h
+++ b/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);
 
diff --git a/Source/Core/Core/IOS/ES/Formats.cpp b/Source/Core/Core/IOS/ES/Formats.cpp
index 6039cacb8c..2af15c0c70 100644
--- a/Source/Core/Core/IOS/ES/Formats.cpp
+++ b/Source/Core/Core/IOS/ES/Formats.cpp
@@ -130,7 +130,7 @@ std::array<u8, 20> SignedBlobReader::GetSha1() const
 bool SignedBlobReader::IsSignatureValid() const
 {
   // Too small for the certificate type.
-  if (m_bytes.size() < sizeof(Cert::type))
+  if (m_bytes.size() < sizeof(SignatureType))
     return false;
 
   // Too small to contain the whole signature data.
@@ -146,20 +146,23 @@ SignatureType SignedBlobReader::GetSignatureType() const
   return static_cast<SignatureType>(Common::swap32(m_bytes.data()));
 }
 
+template <typename T, typename It>
+static std::vector<u8> DetailGetSignatureData(It begin)
+{
+  const auto signature_begin = begin + offsetof(T, sig);
+  return std::vector<u8>(signature_begin, signature_begin + sizeof(T::sig));
+}
+
 std::vector<u8> SignedBlobReader::GetSignatureData() const
 {
   switch (GetSignatureType())
   {
   case SignatureType::RSA4096:
-  {
-    const auto signature_begin = m_bytes.begin() + offsetof(SignatureRSA4096, sig);
-    return std::vector<u8>(signature_begin, signature_begin + sizeof(SignatureRSA4096::sig));
-  }
+    return DetailGetSignatureData<SignatureRSA4096>(m_bytes.cbegin());
   case SignatureType::RSA2048:
-  {
-    const auto signature_begin = m_bytes.begin() + offsetof(SignatureRSA2048, sig);
-    return std::vector<u8>(signature_begin, signature_begin + sizeof(SignatureRSA2048::sig));
-  }
+    return DetailGetSignatureData<SignatureRSA2048>(m_bytes.cbegin());
+  case SignatureType::ECC:
+    return DetailGetSignatureData<SignatureECC>(m_bytes.cbegin());
   default:
     return {};
   }
@@ -173,27 +176,30 @@ size_t SignedBlobReader::GetSignatureSize() const
     return sizeof(SignatureRSA4096);
   case SignatureType::RSA2048:
     return sizeof(SignatureRSA2048);
+  case SignatureType::ECC:
+    return sizeof(SignatureECC);
   default:
     return 0;
   }
 }
 
+template <typename T>
+static std::string DetailGetIssuer(const u8* bytes)
+{
+  const char* issuer = reinterpret_cast<const char*>(bytes + offsetof(T, issuer));
+  return {issuer, strnlen(issuer, sizeof(T::issuer))};
+}
+
 std::string SignedBlobReader::GetIssuer() const
 {
   switch (GetSignatureType())
   {
   case SignatureType::RSA4096:
-  {
-    const char* issuer =
-        reinterpret_cast<const char*>(m_bytes.data() + offsetof(SignatureRSA4096, issuer));
-    return std::string(issuer, strnlen(issuer, sizeof(SignatureRSA4096::issuer)));
-  }
+    return DetailGetIssuer<SignatureRSA4096>(m_bytes.data());
   case SignatureType::RSA2048:
-  {
-    const char* issuer =
-        reinterpret_cast<const char*>(m_bytes.data() + offsetof(SignatureRSA2048, issuer));
-    return std::string(issuer, strnlen(issuer, sizeof(SignatureRSA2048::issuer)));
-  }
+    return DetailGetIssuer<SignatureRSA2048>(m_bytes.data());
+  case SignatureType::ECC:
+    return DetailGetIssuer<SignatureECC>(m_bytes.data());
   default:
     return "";
   }
@@ -677,24 +683,22 @@ CertReader::CertReader(std::vector<u8>&& bytes) : SignedBlobReader(std::move(byt
   if (!IsSignatureValid())
     return;
 
-  switch (GetSignatureType())
-  {
-  case SignatureType::RSA4096:
-    if (m_bytes.size() < sizeof(CertRSA4096))
-      return;
-    m_bytes.resize(sizeof(CertRSA4096));
-    break;
+  static constexpr std::array<std::tuple<SignatureType, PublicKeyType, size_t>, 4> types{{
+      {SignatureType::RSA4096, PublicKeyType::RSA2048, sizeof(CertRSA4096RSA2048)},
+      {SignatureType::RSA2048, PublicKeyType::RSA2048, sizeof(CertRSA2048RSA2048)},
+      {SignatureType::RSA2048, PublicKeyType::ECC, sizeof(CertRSA2048ECC)},
+      {SignatureType::ECC, PublicKeyType::ECC, sizeof(CertECC)},
+  }};
 
-  case SignatureType::RSA2048:
-    if (m_bytes.size() < sizeof(CertRSA2048))
-      return;
-    m_bytes.resize(sizeof(CertRSA2048));
-    break;
+  const auto info = std::find_if(types.cbegin(), types.cend(), [this](const auto& entry) {
+    return m_bytes.size() >= std::get<2>(entry) && std::get<0>(entry) == GetSignatureType() &&
+           std::get<1>(entry) == GetPublicKeyType();
+  });
 
-  default:
+  if (info == types.cend())
     return;
-  }
 
+  m_bytes.resize(std::get<2>(*info));
   m_is_valid = true;
 }
 
@@ -722,20 +726,28 @@ PublicKeyType CertReader::GetPublicKeyType() const
   return static_cast<PublicKeyType>(Common::swap32(m_bytes.data() + offset));
 }
 
-std::vector<u8> CertReader::GetPublicKey() const
+template <typename T, typename It>
+std::vector<u8> DetailGetPublicKey(It begin, size_t extra_data = 0)
 {
-  static const std::map<SignatureType, std::pair<size_t, size_t>> type_to_key_info = {{
-      {SignatureType::RSA4096,
-       {offsetof(CertRSA4096, public_key),
-        sizeof(CertRSA4096::public_key) + sizeof(CertRSA4096::exponent)}},
-      {SignatureType::RSA2048,
-       {offsetof(CertRSA2048, public_key),
-        sizeof(CertRSA2048::public_key) + sizeof(CertRSA2048::exponent)}},
-  }};
+  const auto key_begin = begin + offsetof(T, public_key);
+  return {key_begin, key_begin + sizeof(T::public_key) + extra_data};
+}
 
-  const auto info = type_to_key_info.at(GetSignatureType());
-  const auto key_begin = m_bytes.begin() + info.first;
-  return std::vector<u8>(key_begin, key_begin + info.second);
+std::vector<u8> CertReader::GetPublicKey() const
+{
+  switch (GetSignatureType())
+  {
+  case SignatureType::RSA4096:
+    return DetailGetPublicKey<CertRSA4096RSA2048>(m_bytes.begin(), 4);
+  case SignatureType::RSA2048:
+    if (GetPublicKeyType() == PublicKeyType::RSA2048)
+      return DetailGetPublicKey<CertRSA2048RSA2048>(m_bytes.begin(), 4);
+    return DetailGetPublicKey<CertRSA2048ECC>(m_bytes.begin());
+  case SignatureType::ECC:
+    return DetailGetPublicKey<CertECC>(m_bytes.begin());
+  default:
+    return {};
+  }
 }
 
 std::map<std::string, CertReader> ParseCertChain(const std::vector<u8>& chain)
diff --git a/Source/Core/Core/IOS/ES/Identity.cpp b/Source/Core/Core/IOS/ES/Identity.cpp
index 134ccdc60b..87ff012cb6 100644
--- a/Source/Core/Core/IOS/ES/Identity.cpp
+++ b/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
diff --git a/Source/Core/Core/IOS/IOSC.cpp b/Source/Core/Core/IOS/IOSC.cpp
index 569568395d..7d791b3f9d 100644
--- a/Source/Core/Core/IOS/IOSC.cpp
+++ b/Source/Core/Core/IOS/IOSC.cpp
@@ -337,8 +337,12 @@ ReturnCode IOSC::VerifyPublicKeySign(const std::array<u8, 20>& sha1, Handle sign
     return IPC_SUCCESS;
   }
   case SUBTYPE_ECC233:
-    ERROR_LOG(IOS, "VerifyPublicKeySign: SUBTYPE_ECC233 is unimplemented");
-  // [[fallthrough]]
+  {
+    ASSERT(entry->data.size() == sizeof(CertECC::public_key));
+
+    const bool ok = Common::ec::VerifySignature(entry->data.data(), signature.data(), sha1.data());
+    return ok ? IPC_SUCCESS : IOSC_FAIL_CHECKVALUE;
+  }
   default:
     return IOSC_INVALID_OBJTYPE;
   }
diff --git a/Source/Core/Core/IOS/IOSC.h b/Source/Core/Core/IOS/IOSC.h
index c397b85a5c..5207f4c9f0 100644
--- a/Source/Core/Core/IOS/IOSC.h
+++ b/Source/Core/Core/IOS/IOSC.h
@@ -34,6 +34,7 @@ enum class PublicKeyType : u32
 {
   RSA4096 = 0,
   RSA2048 = 1,
+  ECC = 2,
 };
 
 #pragma pack(push, 4)
@@ -72,34 +73,48 @@ struct CertHeader
   u32 id;
 };
 
-struct CertRSA4096
+using RSA2048PublicKey = std::array<u8, 0x100>;
+using ECCPublicKey = std::array<u8, 60>;
+
+struct CertRSA4096RSA2048
 {
   SignatureRSA4096 signature;
   CertHeader header;
-  // The signature is RSA4096, but the key is a RSA2048 public key,
-  // so its size is 0x100, not 0x200, as one would expect from the name.
-  u8 public_key[0x100];
+  RSA2048PublicKey public_key;
   u8 exponent[0x4];
   u8 pad[0x34];
 };
-static_assert(sizeof(CertRSA4096) == 0x400, "Wrong size for CertRSA4096");
+static_assert(sizeof(CertRSA4096RSA2048) == 0x400, "Wrong size for CertRSA4096RSA2048");
 
-struct CertRSA2048
+struct CertRSA2048RSA2048
 {
   SignatureRSA2048 signature;
   CertHeader header;
-  u8 public_key[0x100];
+  RSA2048PublicKey public_key;
   u8 exponent[0x4];
   u8 pad[0x34];
 };
-static_assert(sizeof(CertRSA2048) == 0x300, "Wrong size for CertRSA2048");
+static_assert(sizeof(CertRSA2048RSA2048) == 0x300, "Wrong size for CertRSA2048RSA2048");
 
-union Cert
+/// Used for device certificates
+struct CertRSA2048ECC
 {
-  SignatureType type;
-  CertRSA4096 rsa4096;
-  CertRSA2048 rsa2048;
+  SignatureRSA2048 signature;
+  CertHeader header;
+  ECCPublicKey public_key;
+  std::array<u8, 60> padding;
+};
+static_assert(sizeof(CertRSA2048ECC) == 0x240, "Wrong size for CertRSA2048ECC");
+
+/// Used for device signed certificates
+struct CertECC
+{
+  SignatureECC signature;
+  CertHeader header;
+  ECCPublicKey public_key;
+  std::array<u8, 60> padding;
 };
+static_assert(sizeof(CertECC) == 0x180, "Wrong size for CertECC");
 #pragma pack(pop)
 
 using ECCSignature = std::array<u8, 60>;