sshbuf_dtob64
if (sshbuf_dtob64(buf, tmp, wrap) != 0) {
if ((r = sshbuf_dtob64(d, b, wrap)) != 0)
int sshbuf_dtob64(const struct sshbuf *d, struct sshbuf *b64, int wrap);
(r = sshbuf_dtob64(encoded, blob, 1)) != 0 ||
if ((r = sshbuf_dtob64(blob, buf, 1)) != 0) {