Define OPENSSL_NO_TLS_PHA, typedef PSK callback signatures (#1526)

This commit defines a new configuration macro `OPENSSL_NO_TLS_PHA`. This
macro is meant to be used by consuming applications to detect the fact
that we (or other `libssl`s) don't support TLSv1.3's post-handshake
authentication (PHA). We then use this macro in place of
`OPENSSL_IS_AWSLC` to detect PHA support in our CPython patch.

We also enable PSK in our CPython patch and create two PSK-related
callback function signatures [defined by OpenSSL][1] and used by
CPython.

Finally, we fix the now-executed PSK tests in CPython.

[1]:
https://www.openssl.org/docs/man1.1.1/man3/SSL_psk_client_cb_func.html

include/openssl/opensslconf.h

@@ -19,6 +19,11 @@
 #define OPENSSL_HEADER_OPENSSLCONF_H
 
 
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
 #define OPENSSL_NO_ASYNC
 #define OPENSSL_NO_BF
 #define OPENSSL_NO_BLAKE2
@@ -48,6 +53,11 @@
 #define OPENSSL_NO_MD2
 #define OPENSSL_NO_MDC2
 #define OPENSSL_NO_OCB
+
+// OPENSSL_NO_TLS_PHA indicates lack of support for post-handshake
+// authentication (PHA) in TLS >= 1.3
+#define OPENSSL_NO_TLS_PHA
+
 #define OPENSSL_NO_RC2
 #define OPENSSL_NO_RC5
 #define OPENSSL_NO_RFC3779
@@ -68,4 +78,10 @@
 #define OPENSSL_NO_TS
 #define OPENSSL_NO_WHIRLPOOL
 
+
+#if defined(__cplusplus)
+}
+#endif
+
+
 #endif // OPENSSL_HEADER_OPENSSLCONF_H

include/openssl/ssl.h

@@ -3584,6 +3584,14 @@ OPENSSL_EXPORT const SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(
 // PSK_MAX_PSK_LEN is the maximum supported length of a pre-shared key.
 #define PSK_MAX_PSK_LEN 256
 
+// SSL_psk_client_cb_func defines a function signature for the client callback.
+typedef unsigned int (*SSL_psk_client_cb_func)(SSL *ssl,
+ const char *hint,
+ char *identity,
+ unsigned int max_identity_len,
+ uint8_t *psk,
+ unsigned max_psk_len);
+
 // SSL_CTX_set_psk_client_callback sets the callback to be called when PSK is
 // negotiated on the client. This callback must be set to enable PSK cipher
 // suites on the client.
@@ -3596,17 +3604,19 @@ OPENSSL_EXPORT const SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(
 // The callback returns the length of the PSK or 0 if no suitable identity was
 // found.
 OPENSSL_EXPORT void SSL_CTX_set_psk_client_callback(
- SSL_CTX *ctx, unsigned (*cb)(SSL *ssl, const char *hint, char *identity,
- unsigned max_identity_len, uint8_t *psk,
- unsigned max_psk_len));
+ SSL_CTX *ctx, SSL_psk_client_cb_func cb);
 
 // SSL_set_psk_client_callback sets the callback to be called when PSK is
 // negotiated on the client. This callback must be set to enable PSK cipher
 // suites on the client. See also |SSL_CTX_set_psk_client_callback|.
 OPENSSL_EXPORT void SSL_set_psk_client_callback(
- SSL *ssl, unsigned (*cb)(SSL *ssl, const char *hint, char *identity,
- unsigned max_identity_len, uint8_t *psk,
- unsigned max_psk_len));
+ SSL *ssl, SSL_psk_client_cb_func cb);
+
+// SSL_psk_server_cb_func defines a function signature for the server callback.
+typedef unsigned (*SSL_psk_server_cb_func)(SSL *ssl,
+ const char *identity,
+ uint8_t *psk,
+ unsigned max_psk_len);
 
 // SSL_CTX_set_psk_server_callback sets the callback to be called when PSK is
 // negotiated on the server. This callback must be set to enable PSK cipher
@@ -3616,15 +3626,13 @@ OPENSSL_EXPORT void SSL_set_psk_client_callback(
 // length at most |max_psk_len| to |psk| and return the number of bytes written
 // or zero if the PSK identity is unknown.
 OPENSSL_EXPORT void SSL_CTX_set_psk_server_callback(
- SSL_CTX *ctx, unsigned (*cb)(SSL *ssl, const char *identity, uint8_t *psk,
- unsigned max_psk_len));
+ SSL_CTX *ctx, SSL_psk_server_cb_func cb);
 
 // SSL_set_psk_server_callback sets the callback to be called when PSK is
 // negotiated on the server. This callback must be set to enable PSK cipher
 // suites on the server. See also |SSL_CTX_set_psk_server_callback|.
 OPENSSL_EXPORT void SSL_set_psk_server_callback(
- SSL *ssl, unsigned (*cb)(SSL *ssl, const char *identity, uint8_t *psk,
- unsigned max_psk_len));
+ SSL *ssl, SSL_psk_server_cb_func cb);
 
 // SSL_CTX_use_psk_identity_hint configures server connections to advertise an
 // identity hint of |identity_hint|. It returns one on success and zero on

ssl/ssl_lib.cc

@@ -2821,36 +2821,25 @@ const char *SSL_get_psk_identity(const SSL *ssl) {
  return session->psk_identity.get();
 }
 
-void SSL_set_psk_client_callback(
- SSL *ssl, unsigned (*cb)(SSL *ssl, const char *hint, char *identity,
- unsigned max_identity_len, uint8_t *psk,
- unsigned max_psk_len)) {
+void SSL_set_psk_client_callback(SSL *ssl, SSL_psk_client_cb_func cb) {
  if (!ssl->config) {
  return;
  }
  ssl->config->psk_client_callback = cb;
 }
 
-void SSL_CTX_set_psk_client_callback(
- SSL_CTX *ctx, unsigned (*cb)(SSL *ssl, const char *hint, char *identity,
- unsigned max_identity_len, uint8_t *psk,
- unsigned max_psk_len)) {
+void SSL_CTX_set_psk_client_callback(SSL_CTX *ctx, SSL_psk_client_cb_func cb) {
  ctx->psk_client_callback = cb;
 }
 
-void SSL_set_psk_server_callback(SSL *ssl,
- unsigned (*cb)(SSL *ssl, const char *identity,
- uint8_t *psk,
- unsigned max_psk_len)) {
+void SSL_set_psk_server_callback(SSL *ssl, SSL_psk_server_cb_func cb) {
  if (!ssl->config) {
  return;
  }
  ssl->config->psk_server_callback = cb;
 }
 
-void SSL_CTX_set_psk_server_callback(
- SSL_CTX *ctx, unsigned (*cb)(SSL *ssl, const char *identity, uint8_t *psk,
- unsigned max_psk_len)) {
+void SSL_CTX_set_psk_server_callback(SSL_CTX *ctx, SSL_psk_server_cb_func cb) {
  ctx->psk_server_callback = cb;
 }
 

tests/ci/integration/python_patch/main/aws-lc-cpython.patch

@@ -12,7 +12,7 @@ index 6e63a88..7dc83d7 100644
  # just check status of PHA flag
  h = client.HTTPSConnection('localhost', 443)
 diff --git a/Lib/test/test_ssl.py b/Lib/test/test_ssl.py
-index 3fa806d..0983212 100644
+index 0e50d09..f4b7b3c 100644
 --- a/Lib/test/test_ssl.py
 +++ b/Lib/test/test_ssl.py
 @@ -41,6 +41,7 @@
@@ -32,15 +32,49 @@ index 3fa806d..0983212 100644
  def seclevel_workaround(*ctxs):
  """"Lower security level to '1' and allow all ciphers for TLS 1.0/1"""
  for ctx in ctxs:
-@@ -3997,6 +4001,7 @@ def test_no_legacy_server_connect(self):
+@@ -4001,6 +4002,7 @@ def test_no_legacy_server_connect(self):
  sni_name=hostname)
 
  @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
 + @unittest.skipIf(Py_OPENSSL_IS_AWSLC, "AWS-LC doesn't support (FF)DHE")
  def test_dh_params(self):
  # Check we can get a connection with ephemeral Diffie-Hellman
  client_context, server_context, hostname = testing_context()
-@@ -4457,7 +4462,10 @@ def server_callback(identity):
+@@ -4364,14 +4366,14 @@ def test_session_handling(self):
+ def test_psk(self):
+ psk = bytes.fromhex('deadbeef')
+
+- client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
++ client_context, server_context, _ = testing_context()
++
+ client_context.check_hostname = False
+ client_context.verify_mode = ssl.CERT_NONE
+ client_context.maximum_version = ssl.TLSVersion.TLSv1_2
+ client_context.set_ciphers('PSK')
+ client_context.set_psk_client_callback(lambda hint: (None, psk))
+
+- server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
+ server_context.maximum_version = ssl.TLSVersion.TLSv1_2
+ server_context.set_ciphers('PSK')
+ server_context.set_psk_server_callback(lambda identity: psk)
+@@ -4443,14 +4445,14 @@ def server_callback(identity):
+ self.assertEqual(identity, client_identity)
+ return psk
+
+- client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
++ client_context, server_context, _ = testing_context()
++
+ client_context.check_hostname = False
+ client_context.verify_mode = ssl.CERT_NONE
+ client_context.minimum_version = ssl.TLSVersion.TLSv1_3
+ client_context.set_ciphers('PSK')
+ client_context.set_psk_client_callback(client_callback)
+
+- server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
+ server_context.minimum_version = ssl.TLSVersion.TLSv1_3
+ server_context.set_ciphers('PSK')
+ server_context.set_psk_server_callback(server_callback, identity_hint)
+@@ -4461,7 +4463,10 @@ def server_callback(identity):
  s.connect((HOST, server.port))
 
 
@@ -52,7 +86,7 @@ index 3fa806d..0983212 100644
  class TestPostHandshakeAuth(unittest.TestCase):
  def test_pha_setter(self):
  protocols = [
-@@ -4733,6 +4741,31 @@ def test_internal_chain_server(self):
+@@ -4737,6 +4742,31 @@ def test_internal_chain_server(self):
  self.assertEqual(res, b'\x02\n')
 
 
@@ -106,24 +140,22 @@ index cd1cf24..53bcc4c 100644
  # The _tkinter module.
  #
 diff --git a/Modules/_ssl.c b/Modules/_ssl.c
-index d00f407..7049f79 100644
+index f7fdbf4..204d501 100644
 --- a/Modules/_ssl.c
 +++ b/Modules/_ssl.c
-@@ -188,6 +188,13 @@ extern const SSL_METHOD *TLSv1_2_method(void);
+@@ -187,6 +187,11 @@ extern const SSL_METHOD *TLSv1_2_method(void);
  #endif
-
-
-+
-+#if defined(OPENSSL_IS_AWSLC) || !defined(TLS1_3_VERSION) || defined(OPENSSL_NO_TLS1_3)
+
+
++#if defined(OPENSSL_NO_TLS_PHA) || !defined(TLS1_3_VERSION) || defined(OPENSSL_NO_TLS1_3)
 + #define PY_SSL_NO_POST_HS_AUTH
-+ #define OPENSSL_NO_PSK
 +#endif
 +
 +
  enum py_ssl_error {
  /* these mirror ssl.h */
  PY_SSL_ERROR_NONE,
-@@ -232,7 +239,7 @@ enum py_proto_version {
+@@ -231,7 +236,7 @@ enum py_proto_version {
  PY_PROTO_TLSv1 = TLS1_VERSION,
  PY_PROTO_TLSv1_1 = TLS1_1_VERSION,
  PY_PROTO_TLSv1_2 = TLS1_2_VERSION,
@@ -132,7 +164,7 @@ index d00f407..7049f79 100644
  PY_PROTO_TLSv1_3 = TLS1_3_VERSION,
  #else
  PY_PROTO_TLSv1_3 = 0x304,
-@@ -294,7 +301,7 @@ typedef struct {
+@@ -293,7 +298,7 @@ typedef struct {
  */
  unsigned int hostflags;
  int protocol;
@@ -141,7 +173,7 @@ index d00f407..7049f79 100644
  int post_handshake_auth;
  #endif
  PyObject *msg_cb;
-@@ -886,7 +893,7 @@ newPySSLSocket(PySSLContext *sslctx, PySocketSockObject *sock,
+@@ -873,7 +878,7 @@ newPySSLSocket(PySSLContext *sslctx, PySocketSockObject *sock,
  SSL_set_mode(self->ssl,
  SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | SSL_MODE_AUTO_RETRY);
 
@@ -150,15 +182,15 @@ index d00f407..7049f79 100644
  if (sslctx->post_handshake_auth == 1) {
  if (socket_type == PY_SSL_SERVER) {
  /* bpo-37428: OpenSSL does not ignore SSL_VERIFY_POST_HANDSHAKE.
-@@ -1029,6 +1036,7 @@ _ssl__SSLSocket_do_handshake_impl(PySSLSocket *self)
+@@ -1016,6 +1021,7 @@ _ssl__SSLSocket_do_handshake_impl(PySSLSocket *self)
  } while (err.ssl == SSL_ERROR_WANT_READ ||
  err.ssl == SSL_ERROR_WANT_WRITE);
  Py_XDECREF(sock);
 +
  if (ret < 1)
- return PySSL_SetError(self, ret, __FILE__, __LINE__);
+ return PySSL_SetError(self, __FILE__, __LINE__);
  if (PySSL_ChainExceptions(self) < 0)
-@@ -2788,7 +2796,7 @@ static PyObject *
+@@ -2775,7 +2781,7 @@ static PyObject *
  _ssl__SSLSocket_verify_client_post_handshake_impl(PySSLSocket *self)
  /*[clinic end generated code: output=532147f3b1341425 input=6bfa874810a3d889]*/
  {
@@ -167,7 +199,7 @@ index d00f407..7049f79 100644
  int err = SSL_verify_client_post_handshake(self->ssl);
  if (err == 0)
  return _setSSLError(get_state_sock(self), NULL, 0, __FILE__, __LINE__);
-@@ -3212,7 +3220,7 @@ _ssl__SSLContext_impl(PyTypeObject *type, int proto_version)
+@@ -3198,7 +3204,7 @@ _ssl__SSLContext_impl(PyTypeObject *type, int proto_version)
  X509_VERIFY_PARAM_set_flags(params, X509_V_FLAG_TRUSTED_FIRST);
  X509_VERIFY_PARAM_set_hostflags(params, self->hostflags);
 
@@ -176,7 +208,7 @@ index d00f407..7049f79 100644
  self->post_handshake_auth = 0;
  SSL_CTX_set_post_handshake_auth(self->ctx, self->post_handshake_auth);
  #endif
-@@ -3590,7 +3598,7 @@ set_maximum_version(PySSLContext *self, PyObject *arg, void *c)
+@@ -3576,7 +3582,7 @@ set_maximum_version(PySSLContext *self, PyObject *arg, void *c)
  return set_min_max_proto_version(self, arg, 1);
  }
 
@@ -185,7 +217,7 @@ index d00f407..7049f79 100644
  static PyObject *
  get_num_tickets(PySSLContext *self, void *c)
  {
-@@ -3621,7 +3629,7 @@ set_num_tickets(PySSLContext *self, PyObject *arg, void *c)
+@@ -3607,7 +3613,7 @@ set_num_tickets(PySSLContext *self, PyObject *arg, void *c)
 
  PyDoc_STRVAR(PySSLContext_num_tickets_doc,
  "Control the number of TLSv1.3 session tickets");
@@ -194,7 +226,7 @@ index d00f407..7049f79 100644
 
  static PyObject *
  get_security_level(PySSLContext *self, void *c)
-@@ -3724,14 +3732,14 @@ set_check_hostname(PySSLContext *self, PyObject *arg, void *c)
+@@ -3710,14 +3716,14 @@ set_check_hostname(PySSLContext *self, PyObject *arg, void *c)
 
  static PyObject *
  get_post_handshake_auth(PySSLContext *self, void *c) {
@@ -211,7 +243,7 @@ index d00f407..7049f79 100644
  static int
  set_post_handshake_auth(PySSLContext *self, PyObject *arg, void *c) {
  if (arg == NULL) {
-@@ -4973,14 +4981,14 @@ static PyGetSetDef context_getsetlist[] = {
+@@ -4959,14 +4965,14 @@ static PyGetSetDef context_getsetlist[] = {
  (setter) _PySSLContext_set_msg_callback, NULL},
  {"sni_callback", (getter) get_sni_callback,
  (setter) set_sni_callback, PySSLContext_sni_callback_doc},

util/doc.config

@@ -63,6 +63,7 @@
  },{
  "Name": "SSL implementation",
  "Headers": [
+ "include/openssl/opensslconf.h",
  "include/openssl/ssl.h"
  ]
  }]