diff options
Diffstat (limited to 'usr.sbin/unbound/util/edns.c')
| -rw-r--r-- | usr.sbin/unbound/util/edns.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/usr.sbin/unbound/util/edns.c b/usr.sbin/unbound/util/edns.c new file mode 100644 index 00000000000..2c4e4a1fd27 --- /dev/null +++ b/usr.sbin/unbound/util/edns.c @@ -0,0 +1,83 @@ +/* + * util/edns.c - handle base EDNS options. + * + * Copyright (c) 2018, NLnet Labs. All rights reserved. + * + * This software is open source. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * Neither the name of the NLNET LABS nor the names of its contributors may + * be used to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED + * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** + * \file + * + * This file contains functions for base EDNS options. + */ + +#include "config.h" + +#include "util/config_file.h" +#include "util/netevent.h" +#include "util/regional.h" +#include "util/data/msgparse.h" +#include "util/data/msgreply.h" + +static int edns_keepalive(struct edns_data* edns_out, struct edns_data* edns_in, + struct comm_point* c, struct regional* region) +{ + if(c->type == comm_udp) + return 1; + + /* To respond with a Keepalive option, the client connection + * must have received one message with a TCP Keepalive EDNS option, + * and that option must have 0 length data. Subsequent messages + * sent on that connection will have a TCP Keepalive option. + */ + if(c->tcp_keepalive || + edns_opt_list_find(edns_in->opt_list, LDNS_EDNS_KEEPALIVE)) { + int keepalive = c->tcp_timeout_msec / 100; + uint8_t data[2]; + data[0] = (uint8_t)((keepalive >> 8) & 0xff); + data[1] = (uint8_t)(keepalive & 0xff); + if(!edns_opt_list_append(&edns_out->opt_list, LDNS_EDNS_KEEPALIVE, + sizeof(data), data, region)) + return 0; + c->tcp_keepalive = 1; + } + return 1; +} + +int apply_edns_options(struct edns_data* edns_out, struct edns_data* edns_in, + struct config_file* cfg, struct comm_point* c, struct regional* region) +{ + if(cfg->do_tcp_keepalive && + !edns_keepalive(edns_out, edns_in, c, region)) + return 0; + + return 1; +} |