+int
+ssh_gssapi_check_mechanism(Gssctxt **ctx, gss_OID oid, const char *host)
+{
+ gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
+ OM_uint32 major, minor;
+ gss_OID_desc spnego_oid = {6, (void *)"\x2B\x06\x01\x05\x05\x02"};
+
+ /* RFC 4462 says we MUST NOT do SPNEGO */
+ if (oid->length == spnego_oid.length &&
+ (memcmp(oid->elements, spnego_oid.elements, oid->length) == 0))
+ return 0; /* false */
+
+ ssh_gssapi_build_ctx(ctx);
+ ssh_gssapi_set_oid(*ctx, oid);
+ major = ssh_gssapi_import_name(*ctx, host);
+ if (!GSS_ERROR(major)) {
+ major = ssh_gssapi_init_ctx(*ctx, 0, GSS_C_NO_BUFFER, &token,
+ NULL);
+ gss_release_buffer(&minor, &token);
+ gss_delete_sec_context(&minor, &(*ctx)->context,
+ GSS_C_NO_BUFFER);
+ }
+
+ if (GSS_ERROR(major))
+ ssh_gssapi_delete_ctx(ctx);
+
+ return (!GSS_ERROR(major));
+}
+