#if OPENSSL_VERSION_NUMBER >= 0x10100000L
# define EXIM_HAVE_OCSP_RESP_COUNT
# define OPENSSL_AUTO_SHA256
+# define EXIM_HAVE_ALPN
#else
# define EXIM_HAVE_EPHEM_RSA_KEX
# define EXIM_HAVE_RAND_PSEUDO
uschar ** errstr );
/* Callbacks */
-#ifdef EXIM_HAVE_OPENSSL_TLSEXT
-static int tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg);
-#endif
#ifndef DISABLE_OCSP
static int tls_server_stapling_cb(SSL *s, void *arg);
#endif
+#ifdef EXIM_HAVE_ALPN
+/*************************************************
+* Callback to handle ALPN *
+*************************************************/
+
+/* SSL_CTX_set_alpn_select_cb() */
+/* Called on server when client offers ALPN, after the SNI callback.
+If set and not e?smtp then we dump the connection */
+
+static int
+tls_server_alpn_cb(SSL *ssl, const uschar ** out, uschar * outlen,
+ const uschar * in, unsigned int inlen, void * arg)
+{
+const exim_openssl_state_st * state = arg;
+
+DEBUG(D_tls)
+ {
+ debug_printf("Received TLS ALPN offer:");
+ for (int pos = 0, siz; pos < inlen; pos += siz+1)
+ {
+ siz = in[pos];
+ if (pos + 1 + siz > inlen) siz = inlen - pos - 1;
+ debug_printf(" '%.*s'", siz, in + pos + 1);
+ }
+ debug_printf("\n");
+ }
+
+/* Look for an acceptable ALPN */
+if ( inlen > 1 /* at least one name */
+ && in[0]+1 == inlen /* filling the vector, so exactly one name */
+ && ( Ustrncmp(in+1, "smtp", in[0]) == 0
+ || Ustrncmp(in+1, "esmtp", in[0]) == 0
+ ) )
+ {
+ *out = in; /* we checked for exactly one, so can just point to it */
+ *outlen = inlen;
+ return SSL_TLSEXT_ERR_OK; /* use ALPN */
+ }
+
+/* Reject unacceptable ALPN */
+/* This will be fatal to the TLS conn; would be nice to kill TCP also */
+return SSL_TLSEXT_ERR_ALERT_FATAL;
+}
+#endif /* EXIM_HAVE_ALPN */
+
+
+
#ifndef DISABLE_OCSP
/*************************************************
tls_certificate */
SSL_CTX_set_tlsext_servername_callback(ctx, tls_servername_cb);
SSL_CTX_set_tlsext_servername_arg(ctx, state);
+# ifdef EXIM_HAVE_ALPN
+ SSL_CTX_set_alpn_select_cb(ctx, tls_server_alpn_cb, state);
+# endif
}
# ifndef DISABLE_OCSP
else /* client */
debug_printf("decoding session: %s\n", ssl_errstring);
}
}
-#ifdef EXIM_HAVE_SESSION_TICKET
- else if ( SSL_SESSION_get_ticket_lifetime_hint(ss) + dt->time_stamp
- < time(NULL))
+ else
{
- DEBUG(D_tls) debug_printf("session expired\n");
- dbfn_delete(dbm_file, key);
- }
+ unsigned long lifetime =
+#ifdef EXIM_HAVE_SESSION_TICKET
+ SSL_SESSION_get_ticket_lifetime_hint(ss);
+#else /* Use, fairly arbitrilarily, what we as server would */
+ f.running_in_test_harness ? 6 : ssl_session_timeout;
#endif
- else if (!SSL_set_session(ssl, ss))
- {
- DEBUG(D_tls)
+ if (lifetime + dt->time_stamp < time(NULL))
{
- ERR_error_string_n(ERR_get_error(),
- ssl_errstring, sizeof(ssl_errstring));
- debug_printf("applying session to ssl: %s\n", ssl_errstring);
+ DEBUG(D_tls) debug_printf("session expired\n");
+ dbfn_delete(dbm_file, key);
+ }
+ else if (!SSL_set_session(ssl, ss))
+ {
+ DEBUG(D_tls)
+ {
+ ERR_error_string_n(ERR_get_error(),
+ ssl_errstring, sizeof(ssl_errstring));
+ debug_printf("applying session to ssl: %s\n", ssl_errstring);
+ }
+ }
+ else
+ {
+ DEBUG(D_tls) debug_printf("good session\n");
+ tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
+ tlsp->verify_override = dt->verify_override;
+ tlsp->ocsp = dt->ocsp;
}
- }
- else
- {
- DEBUG(D_tls) debug_printf("good session\n");
- tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
- tlsp->verify_override = dt->verify_override;
- tlsp->ocsp = dt->ocsp;
}
}
else