Mitigate the CRIME TLS flaw

If an attacker can cause a device to make an authenticated request to
a service via TLS while including a payload of the attacker's choice
in that request, and if TLS compression is enabled, the attacker can
uncover the plaintext authentication information by making a series of
guesses and observing changes in the length of the ciphertext.

This is CVE-2012-4929.

FS-6360 --resolve

Thanks-to: Brian West <brian@freeswitch.org>

diff --git a/libs/sofia-sip/libsofia-sip-ua/tport/tport_tls.c b/libs/sofia-sip/libsofia-sip-ua/tport/tport_tls.c
index 07218159db46315e707805969276af945b8d8850..97bc5b98accd9c2bfe8c74c750f4cbdabc75826d 100644 (file)
--- a/libs/sofia-sip/libsofia-sip-ua/tport/tport_tls.c
+++ b/libs/sofia-sip/libsofia-sip-ua/tport/tport_tls.c
@@ -334,6 +334,8 @@ int tls_init_context(tls_t *tls, tls_issues_t const *ti)
     SSL_CTX_set_options(tls->ctx, SSL_OP_NO_TLSv1_2);
   SSL_CTX_sess_set_remove_cb(tls->ctx, NULL);
   SSL_CTX_set_timeout(tls->ctx, ti->timeout);
+  /* CRIME (CVE-2012-4929) mitigation */
+  SSL_CTX_set_options(tls->ctx, SSL_OP_NO_COMPRESSION);
 
   /* Set callback if we have a passphrase */
   if (ti->passphrase != NULL) {