Log TLS signature algorithms

CMakeLists.txt

@@ -570,6 +570,20 @@ check_symbol_exists(SSL_CTX_get0_implemented_groups "openssl/ssl.h" HAVE_SSL_CTX
 check_symbol_exists(SSL_get_group_id "openssl/ssl.h" HAVE_SSL_GET_GROUP_ID)
 check_symbol_exists(SSL_get_group_name "openssl/ssl.h" HAVE_SSL_GET_GROUP_NAME)
 check_symbol_exists(SSL_group_to_name "openssl/ssl.h" HAVE_SSL_GROUP_TO_NAME)
+check_symbol_exists(SSL_get_sigalgs "openssl/ssl.h" HAVE_SSL_GET_SIGALGS)
+check_symbol_exists(SSL_get_shared_sigalgs "openssl/ssl.h" HAVE_SSL_GET_SHARED_SIGALGS)
+check_symbol_exists(SSL_get0_peer_verify_algorithms "openssl/ssl.h" HAVE_SSL_GET0_PEER_VERIFY_ALGORITHMS)
+check_symbol_exists(SSL_get_signature_algorithm_used "openssl/ssl.h" HAVE_SSL_GET_SIGNATURE_ALGORITHM_USED)
+check_cxx_source_compiles(
+  "#include <openssl/ssl.h>
+  int main() {
+    SSL *ssl = nullptr;
+    int digest = 0;
+    int type = 0;
+    return SSL_get_signature_nid(ssl, &digest) + SSL_get_signature_type_nid(ssl, &type);
+  }"
+  HAVE_SSL_GET_LOCAL_SIGNATURE_NIDS
+)
 check_symbol_exists(SSL_set_max_early_data "openssl/ssl.h" HAVE_SSL_SET_MAX_EARLY_DATA)
 check_symbol_exists(SSL_read_early_data "openssl/ssl.h" HAVE_SSL_READ_EARLY_DATA)
 check_symbol_exists(SSL_write_early_data "openssl/ssl.h" HAVE_SSL_WRITE_EARLY_DATA)

doc/admin-guide/logging/formatting.en.rst

@@ -691,6 +691,9 @@ SSL / Encryption
 .. _cqssv:
 .. _cqssc:
 .. _cqssu:
+.. _cqssg:
+.. _cqssig:
+.. _cqssin:
 .. _cqssa:
 .. _cthbr:
 .. _cthbt:
@@ -730,6 +733,15 @@ cqssg  Client Request SSL Group used by |TS| to communicate with the client.
                       This field is only applicable when building |TS| against
                       OpenSSL 3.2 or later or a version of BoringSSL that
                       supports querying group names.
+cqssig Client Request TLS signature schemes offered by the client, rendered as
+                      dash-separated decimal IANA code points in wire order.
+                      RFC 8701 GREASE values are omitted. This field contains
+                      ``-`` when the client does not send the extension or the
+                      TLS library cannot expose it.
+cqssin Client Request TLS signature scheme used by |TS| to authenticate the
+                      handshake, rendered as a decimal IANA code point. Resumed
+                      sessions contain ``-`` because they do not create a new
+                      handshake signature.
 cqssa  Client Request ALPN Protocol ID negotiated with the client.
 cthbr  Client Request TLS handshake bytes received from the client. This is the
                       number of bytes read from the client during the TLS

include/iocore/net/TLSBasicSupport.h

@@ -26,6 +26,7 @@
 
 #include <string>
 #include <string_view>
+#include <optional>
 
 #include <openssl/ssl.h>
 
@@ -49,6 +50,11 @@ class TLSBasicSupport
   const char      *get_tls_cipher_suite() const;
   const char      *get_tls_curve() const;
   std::string_view get_tls_group() const;
+  std::string_view get_tls_offered_signature_algorithms() const;
+  std::string_view get_tls_negotiated_signature_algorithm() const;
+  void             capture_tls_offered_signature_algorithms();
+  void             capture_tls_offered_signature_algorithms(std::string offered);
+  void             capture_tls_negotiated_signature_algorithm();
   ink_hrtime       get_tls_handshake_begin_time() const;
   ink_hrtime       get_tls_handshake_end_time() const;
   bool             get_tls_handshake_bytes(uint64_t &bytes_in, uint64_t &bytes_out) const;
@@ -83,9 +89,11 @@ class TLSBasicSupport
 protected:
   void clear();
 
-  virtual SSL             *_get_ssl_object() const = 0;
-  virtual ssl_curve_id     _get_tls_curve() const  = 0;
-  virtual std::string_view _get_tls_group() const  = 0;
+  virtual SSL             *_get_ssl_object() const                         = 0;
+  virtual ssl_curve_id     _get_tls_curve() const                          = 0;
+  virtual std::string_view _get_tls_group() const                          = 0;
+  virtual std::string      _get_tls_offered_signature_algorithms() const   = 0;
+  virtual std::string      _get_tls_negotiated_signature_algorithm() const = 0;
 
   void _record_tls_handshake_begin_time();
   void _record_tls_handshake_end_time();
@@ -103,9 +111,11 @@ class TLSBasicSupport
 
   X509_STORE_CTX *_cert_to_verify = nullptr;
 
-  ink_hrtime       _tls_handshake_begin_time     = 0;
-  ink_hrtime       _tls_handshake_end_time       = 0;
-  mutable bool     _tls_handshake_bytes_measured = false;
-  mutable uint64_t _tls_handshake_bytes_in       = 0;
-  mutable uint64_t _tls_handshake_bytes_out      = 0;
+  ink_hrtime                         _tls_handshake_begin_time     = 0;
+  ink_hrtime                         _tls_handshake_end_time       = 0;
+  mutable bool                       _tls_handshake_bytes_measured = false;
+  mutable uint64_t                   _tls_handshake_bytes_in       = 0;
+  mutable uint64_t                   _tls_handshake_bytes_out      = 0;
+  mutable std::optional<std::string> _tls_offered_signature_algorithms;
+  mutable std::optional<std::string> _tls_negotiated_signature_algorithm;
 };

include/proxy/http/HttpUserAgent.h

@@ -54,6 +54,8 @@ struct ClientConnectionInfo {
   char const *cipher_suite{"-"};
   char const *curve{"-"};
   std::string security_group{"-"};
+  std::string offered_signature_algorithms{"-"};
+  std::string negotiated_signature_algorithm{"-"};
 
   int alpn_id{SessionProtocolNameRegistry::INVALID};
 
@@ -101,6 +103,10 @@ class HttpUserAgent
 
   char const *get_client_security_group() const;
 
+  char const *get_client_offered_signature_algorithms() const;
+
+  char const *get_client_negotiated_signature_algorithm() const;
+
   int get_client_alpn_id() const;
 
   uint64_t get_client_tls_handshake_bytes_rx() const;
@@ -193,6 +199,19 @@ HttpUserAgent::set_txn(ProxyTransaction *txn, TransactionMilestones &milestones)
       m_conn_info.security_group = '-';
     }
 
+    if (auto offered_signature_algorithms{tbs->get_tls_offered_signature_algorithms()}; !offered_signature_algorithms.empty()) {
+      m_conn_info.offered_signature_algorithms = offered_signature_algorithms;
+    } else {
+      m_conn_info.offered_signature_algorithms = '-';
+    }
+
+    if (auto negotiated_signature_algorithm{tbs->get_tls_negotiated_signature_algorithm()};
+        !negotiated_signature_algorithm.empty()) {
+      m_conn_info.negotiated_signature_algorithm = negotiated_signature_algorithm;
+    } else {
+      m_conn_info.negotiated_signature_algorithm = '-';
+    }
+
     if (!m_conn_info.tcp_reused) {
       // Copy along the TLS handshake timings
       milestones[TS_MILESTONE_TLS_HANDSHAKE_START] = tbs->get_tls_handshake_begin_time();
@@ -312,6 +331,18 @@ HttpUserAgent::get_client_security_group() const
   return m_conn_info.security_group.c_str();
 }
 
+inline char const *
+HttpUserAgent::get_client_offered_signature_algorithms() const
+{
+  return m_conn_info.offered_signature_algorithms.c_str();
+}
+
+inline char const *
+HttpUserAgent::get_client_negotiated_signature_algorithm() const
+{
+  return m_conn_info.negotiated_signature_algorithm.c_str();
+}
+
 inline int
 HttpUserAgent::get_client_alpn_id() const
 {

include/proxy/logging/LogAccess.h

@@ -134,51 +134,53 @@ class LogAccess
   //
   // client -> proxy fields
   //
-  int marshal_client_host_ip(char *);                // STR
-  int marshal_host_interface_ip(char *);             // STR
-  int marshal_client_host_ip_verified(char *);       // STR
-  int marshal_client_host_port(char *);              // INT
-  int marshal_remote_host_ip(char *);                // STR
-  int marshal_remote_host_port(char *);              // STR
-  int marshal_client_auth_user_name(char *);         // STR
-  int marshal_client_req_timestamp_sec(char *);      // INT
-  int marshal_client_req_timestamp_ms(char *);       // INT
-  int marshal_client_req_text(char *);               // STR
-  int marshal_client_req_http_method(char *);        // STR
-  int marshal_client_req_url(char *);                // STR
-  int marshal_client_req_url_canon(char *);          // STR
-  int marshal_client_req_unmapped_url_canon(char *); // STR
-  int marshal_client_req_unmapped_url_path(char *);  // STR
-  int marshal_client_req_unmapped_url_host(char *);  // STR
-  int marshal_client_req_url_path(char *);           // STR
-  int marshal_client_req_url_scheme(char *);         // STR
-  int marshal_client_req_http_version(char *);       // INT
-  int marshal_client_req_protocol_version(char *);   // STR
-  int marshal_server_req_protocol_version(char *);   // STR
-  int marshal_client_req_squid_len(char *);          // INT
-  int marshal_client_req_squid_len_tls(char *);      // INT
-  int marshal_client_req_header_len(char *);         // INT
-  int marshal_client_req_content_len(char *);        // INT
-  int marshal_client_req_tcp_reused(char *);         // INT
-  int marshal_client_req_is_ssl(char *);             // INT
-  int marshal_client_req_ssl_reused(char *);         // INT
-  int marshal_client_ssl_resumption_type(char *);    // INT
-  int marshal_client_req_is_internal(char *);        // INT
-  int marshal_client_req_mptcp_state(char *);        // INT
-  int marshal_client_security_protocol(char *);      // STR
-  int marshal_client_security_cipher_suite(char *);  // STR
-  int marshal_client_security_curve(char *);         // STR
-  int marshal_client_security_group(char *);         // STR
-  int marshal_client_security_alpn(char *);          // STR
-  int marshal_client_finish_status_code(char *);     // INT
-  int marshal_client_req_id(char *);                 // INT
-  int marshal_client_req_uuid(char *);               // STR
-  int marshal_client_rx_error_code(char *);          // STR
-  int marshal_client_tx_error_code(char *);          // STR
-  int marshal_client_tls_handshake_bytes_rx(char *); // INT
-  int marshal_client_tls_handshake_bytes_tx(char *); // INT
-  int marshal_client_tls_handshake_bytes(char *);    // INT
-  int marshal_client_req_all_header_fields(char *);  // STR
+  int marshal_client_host_ip(char *);                        // STR
+  int marshal_host_interface_ip(char *);                     // STR
+  int marshal_client_host_ip_verified(char *);               // STR
+  int marshal_client_host_port(char *);                      // INT
+  int marshal_remote_host_ip(char *);                        // STR
+  int marshal_remote_host_port(char *);                      // STR
+  int marshal_client_auth_user_name(char *);                 // STR
+  int marshal_client_req_timestamp_sec(char *);              // INT
+  int marshal_client_req_timestamp_ms(char *);               // INT
+  int marshal_client_req_text(char *);                       // STR
+  int marshal_client_req_http_method(char *);                // STR
+  int marshal_client_req_url(char *);                        // STR
+  int marshal_client_req_url_canon(char *);                  // STR
+  int marshal_client_req_unmapped_url_canon(char *);         // STR
+  int marshal_client_req_unmapped_url_path(char *);          // STR
+  int marshal_client_req_unmapped_url_host(char *);          // STR
+  int marshal_client_req_url_path(char *);                   // STR
+  int marshal_client_req_url_scheme(char *);                 // STR
+  int marshal_client_req_http_version(char *);               // INT
+  int marshal_client_req_protocol_version(char *);           // STR
+  int marshal_server_req_protocol_version(char *);           // STR
+  int marshal_client_req_squid_len(char *);                  // INT
+  int marshal_client_req_squid_len_tls(char *);              // INT
+  int marshal_client_req_header_len(char *);                 // INT
+  int marshal_client_req_content_len(char *);                // INT
+  int marshal_client_req_tcp_reused(char *);                 // INT
+  int marshal_client_req_is_ssl(char *);                     // INT
+  int marshal_client_req_ssl_reused(char *);                 // INT
+  int marshal_client_ssl_resumption_type(char *);            // INT
+  int marshal_client_req_is_internal(char *);                // INT
+  int marshal_client_req_mptcp_state(char *);                // INT
+  int marshal_client_security_protocol(char *);              // STR
+  int marshal_client_security_cipher_suite(char *);          // STR
+  int marshal_client_security_curve(char *);                 // STR
+  int marshal_client_security_group(char *);                 // STR
+  int marshal_client_offered_signature_algorithms(char *);   // STR
+  int marshal_client_negotiated_signature_algorithm(char *); // STR
+  int marshal_client_security_alpn(char *);                  // STR
+  int marshal_client_finish_status_code(char *);             // INT
+  int marshal_client_req_id(char *);                         // INT
+  int marshal_client_req_uuid(char *);                       // STR
+  int marshal_client_rx_error_code(char *);                  // STR
+  int marshal_client_tx_error_code(char *);                  // STR
+  int marshal_client_tls_handshake_bytes_rx(char *);         // INT
+  int marshal_client_tls_handshake_bytes_tx(char *);         // INT
+  int marshal_client_tls_handshake_bytes(char *);            // INT
+  int marshal_client_req_all_header_fields(char *);          // STR
 
   //
   // proxy -> client fields

include/proxy/logging/TransactionLogData.h

@@ -130,6 +130,8 @@ class TransactionLogData
   const char *get_client_cipher_suite() const;
   const char *get_client_curve() const;
   const char *get_client_security_group() const;
+  const char *get_client_offered_signature_algorithms() const;
+  const char *get_client_negotiated_signature_algorithm() const;
   int         get_client_alpn_id() const;
 
   // ===== SNI =====

include/tscore/ink_config.h.cmake.in

@@ -183,6 +183,11 @@ const int DEFAULT_STACKSIZE = @DEFAULT_STACK_SIZE@;
 #cmakedefine01 HAVE_SSL_GET_GROUP_ID
 #cmakedefine01 HAVE_SSL_GET_GROUP_NAME
 #cmakedefine01 HAVE_SSL_GROUP_TO_NAME
+#cmakedefine01 HAVE_SSL_GET_SIGALGS
+#cmakedefine01 HAVE_SSL_GET_SHARED_SIGALGS
+#cmakedefine01 HAVE_SSL_GET0_PEER_VERIFY_ALGORITHMS
+#cmakedefine01 HAVE_SSL_GET_SIGNATURE_ALGORITHM_USED
+#cmakedefine01 HAVE_SSL_GET_LOCAL_SIGNATURE_NIDS
 #cmakedefine01 HAVE_SSL_ERROR_DESCRIPTION
 #cmakedefine01 HAVE_OSSL_PARAM_CONSTRUCT_END
 #cmakedefine01 TS_USE_TLS_SET_CIPHERSUITES

src/iocore/net/CMakeLists.txt

@@ -140,6 +140,7 @@ if(BUILD_TESTING)
     NetVCTest.cc
     unit_tests/test_ProxyProtocol.cc
     unit_tests/test_SSLSNIConfig.cc
+    unit_tests/test_SSLUtils.cc
     unit_tests/test_YamlSNIConfig.cc
     unit_tests/unit_test_main.cc
     unit_tests/benchmark_TLSCertCompression.cc

src/iocore/net/P_QUICNetVConnection.h

@@ -160,6 +160,8 @@ class QUICNetVConnection : public UnixNetVConnection,
   SSL             *_get_ssl_object() const override;
   ssl_curve_id     _get_tls_curve() const override;
   std::string_view _get_tls_group() const override;
+  std::string      _get_tls_offered_signature_algorithms() const override;
+  std::string      _get_tls_negotiated_signature_algorithm() const override;
   int              _verify_certificate(X509_STORE_CTX *ctx) override;
 
   // TLSSNISupport

src/iocore/net/P_SSLNetVConnection.h

@@ -319,6 +319,8 @@ class SSLNetVConnection : public UnixNetVConnection,
   }
   ssl_curve_id     _get_tls_curve() const override;
   std::string_view _get_tls_group() const override;
+  std::string      _get_tls_offered_signature_algorithms() const override;
+  std::string      _get_tls_negotiated_signature_algorithm() const override;
   int              _verify_certificate(X509_STORE_CTX *ctx) override;
 
   // TLSSessionResumptionSupport

src/iocore/net/P_SSLUtils.h

@@ -23,6 +23,7 @@
 
 #include "P_SSLCertLookup.h"
 #include "iocore/net/SSLTypes.h"
+#include "swoc/MemSpan.h"
 #include "tscore/Diags.h"
 
 #define OPENSSL_THREAD_DEFINES
@@ -31,6 +32,7 @@
 #endif
 #include <openssl/ssl.h>
 #include <memory>
+#include <string>
 
 class SSLNetVConnection;
 
@@ -42,6 +44,18 @@ ssl_curve_id SSLGetCurveNID(SSL *ssl);
 /// Return the TLS Group Name associated with the specified SSL connection.
 std::string_view SSLGetGroupName(SSL *ssl);
 
+/// Format TLS signature-scheme code points as dash-separated decimal values, excluding GREASE.
+std::string SSLFormatSignatureAlgorithms(swoc::MemSpan<uint16_t const> algorithms);
+
+/// Return the peer's offered TLS signature schemes in wire order.
+std::string SSLGetOfferedSignatureAlgorithms(SSL *ssl);
+
+/// Return the TLS signature scheme used locally to authenticate the current handshake.
+std::string SSLGetNegotiatedSignatureAlgorithm(SSL *ssl);
+
+/// Capture TLS signature information while the TLS library still exposes the selected scheme.
+void SSLHandshakeInfoCallback(const SSL *ssl, int where, int ret);
+
 SSL_SESSION *SSLSessionDup(SSL_SESSION *sess);
 
 enum class SSLCertContextType;

src/iocore/net/QUICMultiCertConfigLoader.cc

@@ -23,6 +23,7 @@
 
 #include "P_SSLCertLookup.h"
 #include "P_SSLConfig.h"
+#include "P_SSLUtils.h"
 #include "iocore/net/QUICMultiCertConfigLoader.h"
 #include "iocore/net/quic/QUICConfig.h"
 #include "mgmt/config/ConfigContextDiags.h"
@@ -107,10 +108,9 @@ QUICMultiCertConfigLoader::_set_cipher_suites_for_legacy_versions(SSL_CTX * /* c
 }
 
 bool
-QUICMultiCertConfigLoader::_set_info_callback(SSL_CTX * /* ctx ATS_UNUSED */)
+QUICMultiCertConfigLoader::_set_info_callback(SSL_CTX *ctx)
 {
-  // Disabled for now
-  // TODO Check if we need this for QUIC
+  SSL_CTX_set_info_callback(ctx, SSLHandshakeInfoCallback);
   return true;
 }
 

src/iocore/net/QUICNetVConnection.cc

@@ -831,6 +831,18 @@ QUICNetVConnection::_get_tls_group() const
   }
 }
 
+std::string
+QUICNetVConnection::_get_tls_offered_signature_algorithms() const
+{
+  return SSLGetOfferedSignatureAlgorithms(this->_ssl);
+}
+
+std::string
+QUICNetVConnection::_get_tls_negotiated_signature_algorithm() const
+{
+  return SSLGetNegotiatedSignatureAlgorithm(this->_ssl);
+}
+
 int
 QUICNetVConnection::_verify_certificate(X509_STORE_CTX * /* ctx ATS_UNUSED */)
 {

src/iocore/net/SSLNetVConnection.cc

@@ -2186,6 +2186,18 @@ SSLNetVConnection::_get_tls_group() const
   }
 }
 
+std::string
+SSLNetVConnection::_get_tls_offered_signature_algorithms() const
+{
+  return SSLGetOfferedSignatureAlgorithms(ssl);
+}
+
+std::string
+SSLNetVConnection::_get_tls_negotiated_signature_algorithm() const
+{
+  return SSLGetNegotiatedSignatureAlgorithm(ssl);
+}
+
 int
 SSLNetVConnection::_verify_certificate(X509_STORE_CTX * /* ctx ATS_UNUSED */)
 {