+
+static void keylog_callback(const SSL *ssl, const char *line)
+{
+ if (bio_keylog == NULL) {
+ BIO_printf(bio_err, "Keylog callback is invoked without valid file!\n");
+ return;
+ }
+
+ /*
+ * There might be concurrent writers to the keylog file, so we must ensure
+ * that the given line is written at once.
+ */
+ BIO_printf(bio_keylog, "%s\n", line);
+ (void)BIO_flush(bio_keylog);
+}
+
+int set_keylog_file(SSL_CTX *ctx, const char *keylog_file)
+{
+ /* Close any open files */
+ BIO_free_all(bio_keylog);
+ bio_keylog = NULL;
+
+ if (ctx == NULL || keylog_file == NULL) {
+ /* Keylogging is disabled, OK. */
+ return 0;
+ }
+
+ /*
+ * Append rather than write in order to allow concurrent modification.
+ * Furthermore, this preserves existing keylog files which is useful when
+ * the tool is run multiple times.
+ */
+ bio_keylog = BIO_new_file(keylog_file, "a");
+ if (bio_keylog == NULL) {
+ BIO_printf(bio_err, "Error writing keylog file %s\n", keylog_file);
+ return 1;
+ }
+
+ /* Write a header for seekable, empty files (this excludes pipes). */
+ if (BIO_tell(bio_keylog) == 0) {
+ BIO_puts(bio_keylog,
+ "# SSL/TLS secrets log file, generated by OpenSSL\n");
+ (void)BIO_flush(bio_keylog);
+ }
+ SSL_CTX_set_keylog_callback(ctx, keylog_callback);
+ return 0;
+}
+
+void print_ca_names(BIO *bio, SSL *s)
+{
+ const char *cs = SSL_is_server(s) ? "server" : "client";
+ const STACK_OF(X509_NAME) *sk = SSL_get0_peer_CA_list(s);
+ int i;
+
+ if (sk == NULL || sk_X509_NAME_num(sk) == 0) {
+ BIO_printf(bio, "---\nNo %s certificate CA names sent\n", cs);
+ return;
+ }
+
+ BIO_printf(bio, "---\nAcceptable %s certificate CA names\n",cs);
+ for (i = 0; i < sk_X509_NAME_num(sk); i++) {
+ X509_NAME_print_ex(bio, sk_X509_NAME_value(sk, i), 0, get_nameopt());
+ BIO_write(bio, "\n", 1);
+ }
+}