+/*
+ * Hex encoder for TLSA RRdata, not ':' delimited.
+ */
+static char *hexencode(const unsigned char *data, size_t len)
+{
+ static const char *hex = "0123456789abcdef";
+ char *out;
+ char *cp;
+ size_t outlen = 2 * len + 1;
+ int ilen = (int) outlen;
+
+ if (outlen < len || ilen < 0 || outlen != (size_t)ilen) {
+ BIO_printf(bio_err, "%s: %" PRIu64 "-byte buffer too large to hexencode\n",
+ opt_getprog(), (uint64_t)len);
+ exit(1);
+ }
+ cp = out = app_malloc(ilen, "TLSA hex data buffer");
+
+ while (ilen-- > 0) {
+ *cp++ = hex[(*data >> 4) & 0x0f];
+ *cp++ = hex[*data++ & 0x0f];
+ }
+ *cp = '\0';
+ return out;
+}
+
+void print_verify_detail(SSL *s, BIO *bio)
+{
+ int mdpth;
+ EVP_PKEY *mspki;
+ long verify_err = SSL_get_verify_result(s);
+
+ if (verify_err == X509_V_OK) {
+ const char *peername = SSL_get0_peername(s);
+
+ BIO_printf(bio, "Verification: OK\n");
+ if (peername != NULL)
+ BIO_printf(bio, "Verified peername: %s\n", peername);
+ } else {
+ const char *reason = X509_verify_cert_error_string(verify_err);
+
+ BIO_printf(bio, "Verification error: %s\n", reason);
+ }
+
+ if ((mdpth = SSL_get0_dane_authority(s, NULL, &mspki)) >= 0) {
+ uint8_t usage, selector, mtype;
+ const unsigned char *data = NULL;
+ size_t dlen = 0;
+ char *hexdata;
+
+ mdpth = SSL_get0_dane_tlsa(s, &usage, &selector, &mtype, &data, &dlen);
+
+ /*
+ * The TLSA data field can be quite long when it is a certificate,
+ * public key or even a SHA2-512 digest. Because the initial octets of
+ * ASN.1 certificates and public keys contain mostly boilerplate OIDs
+ * and lengths, we show the last 12 bytes of the data instead, as these
+ * are more likely to distinguish distinct TLSA records.
+ */
+#define TLSA_TAIL_SIZE 12
+ if (dlen > TLSA_TAIL_SIZE)
+ hexdata = hexencode(data + dlen - TLSA_TAIL_SIZE, TLSA_TAIL_SIZE);
+ else
+ hexdata = hexencode(data, dlen);
+ BIO_printf(bio, "DANE TLSA %d %d %d %s%s %s at depth %d\n",
+ usage, selector, mtype,
+ (dlen > TLSA_TAIL_SIZE) ? "..." : "", hexdata,
+ (mspki != NULL) ? "signed the certificate" :
+ mdpth ? "matched TA certificate" : "matched EE certificate",
+ mdpth);
+ OPENSSL_free(hexdata);
+ }
+}
+