Disable compression for DTLS.

The only standard compression method is stateful and is incompatible with
DTLS.

ssl/ssl_lib.c

@@ -1865,7 +1865,9 @@ SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth)
 	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_SSL_CTX, ret, &ret->ex_data);
 
 	ret->extra_certs=NULL;
-	ret->comp_methods=SSL_COMP_get_compression_methods();
+	/* No compression for DTLS */
+	if (!(meth->ssl3_enc->enc_flags & SSL_ENC_FLAG_DTLS))
+		ret->comp_methods=SSL_COMP_get_compression_methods();
 
 	ret->max_send_fragment = SSL3_RT_MAX_PLAIN_LENGTH;