#ifndef LIBRESSL_VERSION_NUMBER
# if OPENSSL_VERSION_NUMBER >= 0x010100000L
# define EXIM_HAVE_OPENSSL_CHECKHOST
+# define EXIM_HAVE_OPENSSL_DH_BITS
# endif
# if OPENSSL_VERSION_NUMBER >= 0x010000000L \
&& (OPENSSL_VERSION_NUMBER & 0x0000ff000L) >= 0x000002000L
if (preverify_ok == 0)
{
- log_write(0, LOG_MAIN, "[%s] SSL verify error: depth=%d error=%s cert=%s",
- tlsp == &tls_out ? deliver_host_address : sender_host_address,
- depth,
- X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)),
- dn);
+ uschar * extra = verify_mode ? string_sprintf(" (during %c-verify for [%s])",
+ *verify_mode, sender_host_address)
+ : US"";
+ log_write(0, LOG_MAIN, "[%s] SSL verify error%s: depth=%d error=%s cert=%s",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address,
+ extra, depth,
+ X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)), dn);
*calledp = TRUE;
if (!*optionalp)
{
if (rc < 0)
{
log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error",
- deliver_host_address);
+ tlsp == &tls_out ? deliver_host_address : sender_host_address);
name = NULL;
}
break;
if (!tls_is_name_for_cert(verify_cert_hostnames, cert))
#endif
{
+ uschar * extra = verify_mode
+ ? string_sprintf(" (during %c-verify for [%s])",
+ *verify_mode, sender_host_address)
+ : US"";
log_write(0, LOG_MAIN,
- "[%s] SSL verify error: certificate name mismatch: "
- "DN=\"%s\" H=\"%s\"",
- deliver_host_address, dn, verify_cert_hostnames);
+ "[%s] SSL verify error%s: certificate name mismatch: DN=\"%s\" H=\"%s\"",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address,
+ extra, dn, verify_cert_hostnames);
*calledp = TRUE;
if (!*optionalp)
{
DH *dh;
uschar *dhexpanded;
const char *pem;
+int dh_bitsize;
if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded, errstr))
return FALSE;
return FALSE;
}
+/* note: our default limit of 2236 is not a multiple of 8; the limit comes from
+ * an NSS limit, and the GnuTLS APIs handle bit-sizes fine, so we went with
+ * 2236. But older OpenSSL can only report in bytes (octets), not bits.
+ * If someone wants to dance at the edge, then they can raise the limit or use
+ * current libraries. */
+#ifdef EXIM_HAVE_OPENSSL_DH_BITS
+/* Added in commit 26c79d5641d; `git describe --contains` says OpenSSL_1_1_0-pre1~1022
+ * This predates OpenSSL_1_1_0 (before a, b, ...) so is in all 1.1.0 */
+dh_bitsize = DH_bits(dh);
+#else
+dh_bitsize = 8 * DH_size(dh);
+#endif
+
/* Even if it is larger, we silently return success rather than cause things
* to fail out, so that a too-large DH will not knock out all TLS; it's a
* debatable choice. */
-if ((8*DH_size(dh)) > tls_dh_max_bits)
+if (dh_bitsize > tls_dh_max_bits)
{
DEBUG(D_tls)
debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d\n",
- 8*DH_size(dh), tls_dh_max_bits);
+ dh_bitsize, tls_dh_max_bits);
}
else
{
SSL_CTX_set_tmp_dh(sctx, dh);
DEBUG(D_tls)
debug_printf("Diffie-Hellman initialized from %s with %d-bit prime\n",
- dhexpanded ? dhexpanded : US"default", 8*DH_size(dh));
+ dhexpanded ? dhexpanded : US"default", dh_bitsize);
}
DH_free(dh);
#if OPENSSL_VERSION_NUMBER < 0x10002000L
DEBUG(D_tls) debug_printf(
"ECDH OpenSSL < 1.0.2: temp key parameter settings: overriding \"auto\" with \"prime256v1\"\n");
- exp_curve = "prime256v1";
+ exp_curve = US"prime256v1";
#else
# if defined SSL_CTRL_SET_ECDH_AUTO
DEBUG(D_tls) debug_printf(
if (tls_in.active >= 0)
{
tls_error(US"STARTTLS received after TLS started", NULL, US"", errstr);
- smtp_printf("554 Already in TLS\r\n");
+ smtp_printf("554 Already in TLS\r\n", FALSE);
return FAIL;
}
SSL_set_session_id_context(server_ssl, sid_ctx, Ustrlen(sid_ctx));
if (!tls_in.on_connect)
{
- smtp_printf("220 TLS go ahead\r\n");
+ smtp_printf("220 TLS go ahead\r\n", FALSE);
fflush(smtp_out);
}
ssl_xfer_eof = ssl_xfer_error = 0;
receive_getc = tls_getc;
+receive_getbuf = tls_getbuf;
receive_get_cache = tls_get_cache;
receive_ungetc = tls_ungetc;
receive_feof = tls_feof;
+static BOOL
+tls_refill(unsigned lim)
+{
+int error;
+int inbytes;
+
+DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl,
+ ssl_xfer_buffer, ssl_xfer_buffer_size);
+
+if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
+inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer,
+ MIN(ssl_xfer_buffer_size, lim));
+error = SSL_get_error(server_ssl, inbytes);
+alarm(0);
+
+/* SSL_ERROR_ZERO_RETURN appears to mean that the SSL session has been
+closed down, not that the socket itself has been closed down. Revert to
+non-SSL handling. */
+
+if (error == SSL_ERROR_ZERO_RETURN)
+ {
+ DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n");
+
+ receive_getc = smtp_getc;
+ receive_getbuf = smtp_getbuf;
+ receive_get_cache = smtp_get_cache;
+ receive_ungetc = smtp_ungetc;
+ receive_feof = smtp_feof;
+ receive_ferror = smtp_ferror;
+ receive_smtp_buffered = smtp_buffered;
+
+ SSL_free(server_ssl);
+ server_ssl = NULL;
+ tls_in.active = -1;
+ tls_in.bits = 0;
+ tls_in.cipher = NULL;
+ tls_in.peerdn = NULL;
+ tls_in.sni = NULL;
+
+ return FALSE;
+ }
+
+/* Handle genuine errors */
+
+else if (error == SSL_ERROR_SSL)
+ {
+ ERR_error_string(ERR_get_error(), ssl_errstring);
+ log_write(0, LOG_MAIN, "TLS error (SSL_read): %s", ssl_errstring);
+ ssl_xfer_error = 1;
+ return FALSE;
+ }
+
+else if (error != SSL_ERROR_NONE)
+ {
+ DEBUG(D_tls) debug_printf("Got SSL error %d\n", error);
+ ssl_xfer_error = 1;
+ return FALSE;
+ }
+
+#ifndef DISABLE_DKIM
+dkim_exim_verify_feed(ssl_xfer_buffer, inbytes);
+#endif
+ssl_xfer_buffer_hwm = inbytes;
+ssl_xfer_buffer_lwm = 0;
+return TRUE;
+}
+
+
/*************************************************
* TLS version of getc *
*************************************************/
tls_getc(unsigned lim)
{
if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm)
- {
- int error;
- int inbytes;
-
- DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl,
- ssl_xfer_buffer, ssl_xfer_buffer_size);
+ if (!tls_refill(lim))
+ return ssl_xfer_error ? EOF : smtp_getc(lim);
- if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
- inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer,
- MIN(ssl_xfer_buffer_size, lim));
- error = SSL_get_error(server_ssl, inbytes);
- alarm(0);
-
- /* SSL_ERROR_ZERO_RETURN appears to mean that the SSL session has been
- closed down, not that the socket itself has been closed down. Revert to
- non-SSL handling. */
-
- if (error == SSL_ERROR_ZERO_RETURN)
- {
- DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n");
-
- receive_getc = smtp_getc;
- receive_get_cache = smtp_get_cache;
- receive_ungetc = smtp_ungetc;
- receive_feof = smtp_feof;
- receive_ferror = smtp_ferror;
- receive_smtp_buffered = smtp_buffered;
-
- SSL_free(server_ssl);
- server_ssl = NULL;
- tls_in.active = -1;
- tls_in.bits = 0;
- tls_in.cipher = NULL;
- tls_in.peerdn = NULL;
- tls_in.sni = NULL;
-
- return smtp_getc(lim);
- }
+/* Something in the buffer; return next uschar */
- /* Handle genuine errors */
+return ssl_xfer_buffer[ssl_xfer_buffer_lwm++];
+}
- else if (error == SSL_ERROR_SSL)
- {
- ERR_error_string(ERR_get_error(), ssl_errstring);
- log_write(0, LOG_MAIN, "TLS error (SSL_read): %s", ssl_errstring);
- ssl_xfer_error = 1;
- return EOF;
- }
+uschar *
+tls_getbuf(unsigned * len)
+{
+unsigned size;
+uschar * buf;
- else if (error != SSL_ERROR_NONE)
+if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm)
+ if (!tls_refill(*len))
{
- DEBUG(D_tls) debug_printf("Got SSL error %d\n", error);
- ssl_xfer_error = 1;
- return EOF;
+ if (!ssl_xfer_error) return smtp_getbuf(len);
+ *len = 0;
+ return NULL;
}
-#ifndef DISABLE_DKIM
- dkim_exim_verify_feed(ssl_xfer_buffer, inbytes);
-#endif
- ssl_xfer_buffer_hwm = inbytes;
- ssl_xfer_buffer_lwm = 0;
- }
-
-/* Something in the buffer; return next uschar */
-
-return ssl_xfer_buffer[ssl_xfer_buffer_lwm++];
+if ((size = ssl_xfer_buffer_hwm - ssl_xfer_buffer_lwm) > *len)
+ size = *len;
+buf = &ssl_xfer_buffer[ssl_xfer_buffer_lwm];
+ssl_xfer_buffer_lwm += size;
+*len = size;
+return buf;
}
+
void
tls_get_cache()
{
}
+BOOL
+tls_could_read(void)
+{
+return ssl_xfer_buffer_lwm < ssl_xfer_buffer_hwm || SSL_pending(server_ssl) > 0;
+}
+
/*************************************************
* Read bytes from TLS channel *
is_server channel specifier
buff buffer of data
len number of bytes
+ more further data expected soon
Returns: the number of bytes after a successful write,
-1 after a failed write
*/
int
-tls_write(BOOL is_server, const uschar *buff, size_t len)
+tls_write(BOOL is_server, const uschar *buff, size_t len, BOOL more)
{
-int outbytes;
-int error;
-int left = len;
+int outbytes, error, left;
SSL *ssl = is_server ? server_ssl : client_ssl;
+static uschar * corked = NULL;
+static int c_size = 0, c_len = 0;
+
+DEBUG(D_tls) debug_printf("%s(%p, %d%s)\n", __FUNCTION__,
+ buff, len, more ? ", more" : "");
+
+/* Lacking a CORK or MSG_MORE facility (such as GnuTLS has) we copy data when
+"more" is notified. This hack is only ok if small amounts are involved AND only
+one stream does it, in one context (i.e. no store reset). Currently it is used
+for the responses to the received SMTP MAIL , RCPT, DATA sequence, only. */
+
+if (is_server && (more || corked))
+ {
+ corked = string_catn(corked, &c_size, &c_len, buff, len);
+ if (more)
+ return len;
+ buff = CUS corked;
+ len = c_len;
+ corked = NULL; c_size = c_len = 0;
+ }
-DEBUG(D_tls) debug_printf("tls_do_write(%p, %d)\n", buff, left);
-while (left > 0)
+for (left = len; left > 0;)
{
DEBUG(D_tls) debug_printf("SSL_write(SSL, %p, %d)\n", buff, left);
outbytes = SSL_write(ssl, CS buff, left);