+/*
+ * Return 0 if there is only one version configured and it was disabled
+ * at configure time. Return 1 otherwise.
+ */
+static int ssl_check_allowed_versions(int min_version, int max_version)
+{
+ int minisdtls = 0, maxisdtls = 0;
+
+ /* Figure out if we're doing DTLS versions or TLS versions */
+ if (min_version == DTLS1_BAD_VER
+ || min_version >> 8 == DTLS1_VERSION_MAJOR)
+ minisdtls = 1;
+ if (max_version == DTLS1_BAD_VER
+ || max_version >> 8 == DTLS1_VERSION_MAJOR)
+ maxisdtls = 1;
+ /* A wildcard version of 0 could be DTLS or TLS. */
+ if ((minisdtls && !maxisdtls && max_version != 0)
+ || (maxisdtls && !minisdtls && min_version != 0)) {
+ /* Mixing DTLS and TLS versions will lead to sadness; deny it. */
+ return 0;
+ }
+
+ if (minisdtls || maxisdtls) {
+ /* Do DTLS version checks. */
+ if (min_version == 0)
+ /* Ignore DTLS1_BAD_VER */
+ min_version = DTLS1_VERSION;
+ if (max_version == 0)
+ max_version = DTLS1_2_VERSION;
+#ifdef OPENSSL_NO_DTLS1_2
+ if (max_version == DTLS1_2_VERSION)
+ max_version = DTLS1_VERSION;
+#endif
+#ifdef OPENSSL_NO_DTLS1
+ if (min_version == DTLS1_VERSION)
+ min_version = DTLS1_2_VERSION;
+#endif
+ /* Done massaging versions; do the check. */
+ if (0
+#ifdef OPENSSL_NO_DTLS1
+ || (DTLS_VERSION_GE(min_version, DTLS1_VERSION)
+ && DTLS_VERSION_GE(DTLS1_VERSION, max_version))
+#endif
+#ifdef OPENSSL_NO_DTLS1_2
+ || (DTLS_VERSION_GE(min_version, DTLS1_2_VERSION)
+ && DTLS_VERSION_GE(DTLS1_2_VERSION, max_version))
+#endif
+ )
+ return 0;
+ } else {
+ /* Regular TLS version checks. */
+ if (min_version == 0)
+ min_version = SSL3_VERSION;
+ if (max_version == 0)
+ max_version = TLS1_3_VERSION;
+#ifdef OPENSSL_NO_TLS1_3
+ if (max_version == TLS1_3_VERSION)
+ max_version = TLS1_2_VERSION;
+#endif
+#ifdef OPENSSL_NO_TLS1_2
+ if (max_version == TLS1_2_VERSION)
+ max_version = TLS1_1_VERSION;
+#endif
+#ifdef OPENSSL_NO_TLS1_1
+ if (max_version == TLS1_1_VERSION)
+ max_version = TLS1_VERSION;
+#endif
+#ifdef OPENSSL_NO_TLS1
+ if (max_version == TLS1_VERSION)
+ max_version = SSL3_VERSION;
+#endif
+#ifdef OPENSSL_NO_SSL3
+ if (min_version == SSL3_VERSION)
+ min_version = TLS1_VERSION;
+#endif
+#ifdef OPENSSL_NO_TLS1
+ if (min_version == TLS1_VERSION)
+ min_version = TLS1_1_VERSION;
+#endif
+#ifdef OPENSSL_NO_TLS1_1
+ if (min_version == TLS1_1_VERSION)
+ min_version = TLS1_2_VERSION;
+#endif
+#ifdef OPENSSL_NO_TLS1_2
+ if (min_version == TLS1_2_VERSION)
+ min_version = TLS1_3_VERSION;
+#endif
+ /* Done massaging versions; do the check. */
+ if (0
+#ifdef OPENSSL_NO_SSL3
+ || (min_version <= SSL3_VERSION && SSL3_VERSION <= max_version)
+#endif
+#ifdef OPENSSL_NO_TLS1
+ || (min_version <= TLS1_VERSION && TLS1_VERSION <= max_version)
+#endif
+#ifdef OPENSSL_NO_TLS1_1
+ || (min_version <= TLS1_1_VERSION && TLS1_1_VERSION <= max_version)
+#endif
+#ifdef OPENSSL_NO_TLS1_2
+ || (min_version <= TLS1_2_VERSION && TLS1_2_VERSION <= max_version)
+#endif
+#ifdef OPENSSL_NO_TLS1_3
+ || (min_version <= TLS1_3_VERSION && TLS1_3_VERSION <= max_version)
+#endif
+ )
+ return 0;
+ }
+ return 1;
+}
+