Don't select a PSK ciphersuite if no key available
diff --git a/include/polarssl/ssl_ciphersuites.h b/include/polarssl/ssl_ciphersuites.h
index cbea298..8f126b2 100644
--- a/include/polarssl/ssl_ciphersuites.h
+++ b/include/polarssl/ssl_ciphersuites.h
@@ -215,6 +215,7 @@
 #endif
 
 int ssl_ciphersuite_uses_ec( const ssl_ciphersuite_t *info );
+int ssl_ciphersuite_uses_psk( const ssl_ciphersuite_t *info );
 
 #ifdef __cplusplus
 }