gnutls: detect lack of SRP support in GnuTLS at run-time and try without

Reported-by: David Woodhouse
This commit is contained in:
Dan Fandrich 2014-07-14 22:27:03 +02:00
parent 08b27e0892
commit 9087b7e8f5

View File

@ -385,6 +385,10 @@ gtls_connect_step1(struct connectdata *conn,
static int protocol_priority[] = { 0, 0, 0, 0 };
#else
#define GNUTLS_CIPHERS "NORMAL:-ARCFOUR-128:-CTYPE-ALL:+CTYPE-X509"
/* If GnuTLS was compiled without support for SRP it will error out if SRP is
requested in the priority string, so treat it specially
*/
#define GNUTLS_SRP "+SRP"
const char* prioritylist;
const char *err = NULL;
#endif
@ -549,6 +553,9 @@ gtls_connect_step1(struct connectdata *conn,
}
#else
/* Ensure +SRP comes at the *end* of all relevant strings so that it can be
* removed if a run-time error indicates that SRP is not supported by this
* GnuTLS version */
switch (data->set.ssl.version) {
case CURL_SSLVERSION_SSLv3:
prioritylist = GNUTLS_CIPHERS ":-VERS-TLS-ALL:+VERS-SSL3.0";
@ -556,19 +563,19 @@ gtls_connect_step1(struct connectdata *conn,
break;
case CURL_SSLVERSION_DEFAULT:
case CURL_SSLVERSION_TLSv1:
prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:+SRP";
prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:" GNUTLS_SRP;
break;
case CURL_SSLVERSION_TLSv1_0:
prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
"+VERS-TLS1.0:+SRP";
"+VERS-TLS1.0:" GNUTLS_SRP;
break;
case CURL_SSLVERSION_TLSv1_1:
prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
"+VERS-TLS1.1:+SRP";
"+VERS-TLS1.1:" GNUTLS_SRP;
break;
case CURL_SSLVERSION_TLSv1_2:
prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
"+VERS-TLS1.2:+SRP";
"+VERS-TLS1.2:" GNUTLS_SRP;
break;
case CURL_SSLVERSION_SSLv2:
default:
@ -577,6 +584,23 @@ gtls_connect_step1(struct connectdata *conn,
break;
}
rc = gnutls_priority_set_direct(session, prioritylist, &err);
if((rc == GNUTLS_E_INVALID_REQUEST) && err) {
if(!strcmp(err, GNUTLS_SRP)) {
/* This GnuTLS was probably compiled without support for SRP.
* Note that fact and try again without it. */
int validprioritylen = err - prioritylist;
char *prioritycopy = strdup(prioritylist);
if(!prioritycopy)
return CURLE_OUT_OF_MEMORY;
infof(data, "This GnuTLS does not support SRP\n");
if(validprioritylen)
/* Remove the :+SRP */
prioritycopy[validprioritylen - 1] = 0;
rc = gnutls_priority_set_direct(session, prioritycopy, &err);
free(prioritycopy);
}
}
if(rc != GNUTLS_E_SUCCESS) {
failf(data, "Error %d setting GnuTLS cipher list starting with %s",
rc, err);