Chi Hsuan Yen added the comment: With this change: (tested with OpenSSL git-master)
@@ -632,20 +651,22 @@ newPySSLSocket(PySSLContext *sslctx, PyS SSL_set_bio(self->ssl, inbio->bio, outbio->bio); } mode = SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER; #ifdef SSL_MODE_AUTO_RETRY mode |= SSL_MODE_AUTO_RETRY; #endif SSL_set_mode(self->ssl, mode); + if (server_hostname != NULL) { #if HAVE_SNI - if (server_hostname != NULL) SSL_set_tlsext_host_name(self->ssl, server_hostname); #endif + SSL_set1_host(self->ssl, server_hostname); + } /* If the socket is in non-blocking mode or timeout mode, set the BIO * to non-blocking mode (blocking is the default) */ if (sock && sock->sock_timeout >= 0) { BIO_set_nbio(SSL_get_rbio(self->ssl), 1); BIO_set_nbio(SSL_get_wbio(self->ssl), 1); } When connecting to https://wrong.host.badssl.com/, the error is: ssl.SSLCertVerificationError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: Hostname mismatch (_ssl.c:768) With this change in mind, an idea is to drop the Python implementation of match_hostname and rely on OpenSSL's checking mechanism (`do_x509_check`). As a result: * ssl.CertificateError can be either an alias of ssl.SSLCertVerificationError or a subclass of it * When verify_result is X509_V_ERR_HOSTNAME_MISMATCH, the error message is formatted with more information following the current approach in `match_hostname` ("hostname XXX doesn't match YYY...") ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue28182> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com