+
+ if (SSL_version(s) == DTLS1_VERSION)
+ {
+ /* cookie stuff */
+ cookie_len = *(p++);
+
+ if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) &&
+ s->d1->send_cookie == 0)
+ {
+ /* HelloVerifyMessage has already been sent */
+ if ( cookie_len != s->d1->cookie_len)
+ {
+ al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
+ goto f_err;
+ }
+ }
+
+ /*
+ * The ClientHello may contain a cookie even if the
+ * HelloVerify message has not been sent--make sure that it
+ * does not cause an overflow.
+ */
+ if ( cookie_len > sizeof(s->d1->rcvd_cookie))
+ {
+ /* too much data */
+ al = SSL_AD_DECODE_ERROR;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
+ goto f_err;
+ }
+
+ /* verify the cookie if appropriate option is set. */
+ if ( (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) &&
+ cookie_len > 0)
+ {
+ memcpy(s->d1->rcvd_cookie, p, cookie_len);
+
+ if ( s->ctx->app_verify_cookie_cb != NULL)
+ {
+ if ( s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie,
+ cookie_len) == 0)
+ {
+ al=SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
+ SSL_R_COOKIE_MISMATCH);
+ goto f_err;
+ }
+ /* else cookie verification succeeded */
+ }
+ else if ( memcmp(s->d1->rcvd_cookie, s->d1->cookie,
+ s->d1->cookie_len) != 0) /* default verification */
+ {
+ al=SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_SSL3_GET_CLIENT_HELLO,
+ SSL_R_COOKIE_MISMATCH);
+ goto f_err;
+ }
+ }
+
+ p += cookie_len;
+ }
+