File: [local] / src / usr.bin / dig / dighost.c (download)
Revision 1.38, Tue Apr 23 13:34:50 2024 UTC (3 weeks, 4 days ago) by jsg
Branch: MAIN
CVS Tags: HEAD
Changes since 1.37: +3 -4 lines
correct indentation; no functional change
ok tb@
|
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: dighost.c,v 1.38 2024/04/23 13:34:50 jsg Exp $ */
/*! \file
* \note
* Notice to programmers: Do not use this code as an example of how to
* use the ISC library to perform DNS lookups. Dig and Host both operate
* on the request level, since they allow fine-tuning of output and are
* intended as debugging tools. As a result, they perform many of the
* functions which could be better handled using the dns_resolver
* functions in most applications.
*/
#include <sys/socket.h>
#include <sys/time.h>
#include <limits.h>
#include <locale.h>
#include <netdb.h>
#include <resolv.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <stdint.h>
#include <dns/fixedname.h>
#include <dns/log.h>
#include <dns/message.h>
#include <dns/name.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatatype.h>
#include <dns/result.h>
#include <dns/tsig.h>
#include <dst/dst.h>
#include <dst/result.h>
#include <isc/base64.h>
#include <isc/hex.h>
#include <isc/log.h>
#include <isc/result.h>
#include <isc/serial.h>
#include <isc/sockaddr.h>
#include <isc/task.h>
#include <isc/timer.h>
#include <isc/types.h>
#include <isc/util.h>
#include <isccfg/namedconf.h>
#include <lwres/lwres.h>
#include "dig.h"
static lwres_conf_t lwconfdata;
static lwres_conf_t *lwconf = &lwconfdata;
dig_lookuplist_t lookup_list;
dig_serverlist_t server_list;
dig_serverlist_t root_hints_server_list;
dig_searchlistlist_t search_list;
int
check_ra = 0,
have_ipv4 = 1,
have_ipv6 = 1,
specified_source = 0,
free_now = 0,
cancel_now = 0,
usesearch = 0,
showsearch = 0,
qr = 0,
is_dst_up = 0,
keep_open = 0;
in_port_t port = 53;
unsigned int timeout = 0;
unsigned int extrabytes;
isc_log_t *lctx = NULL;
isc_taskmgr_t *taskmgr = NULL;
isc_task_t *global_task = NULL;
isc_timermgr_t *timermgr = NULL;
isc_socketmgr_t *socketmgr = NULL;
struct sockaddr_storage bind_address;
struct sockaddr_storage bind_any;
int sendcount = 0;
int recvcount = 0;
int sockcount = 0;
int ndots = -1;
int tries = 3;
int lookup_counter = 0;
static char sitvalue[256];
isc_socket_t *keep = NULL;
struct sockaddr_storage keepaddr;
static const struct {
const char *ns;
const int af;
} root_hints[] = {
{ "198.41.0.4", AF_INET }, /* a.root-servers.net */
{ "2001:503:ba3e::2:30", AF_INET6 }, /* a.root-servers.net */
{ "199.9.14.201", AF_INET }, /* b.root-servers.net */
{ "2001:500:200::b", AF_INET6 }, /* b.root-servers.net */
{ "192.33.4.12", AF_INET }, /* c.root-servers.net */
{ "2001:500:2::c", AF_INET6 }, /* c.root-servers.net */
{ "199.7.91.13", AF_INET }, /* d.root-servers.net */
{ "2001:500:2d::d", AF_INET6 }, /* d.root-servers.net */
{ "192.203.230.10", AF_INET }, /* e.root-servers.net */
{ "2001:500:a8::e", AF_INET6 }, /* e.root-servers.net */
{ "192.5.5.241", AF_INET }, /* f.root-servers.net */
{ "2001:500:2f::f", AF_INET6 }, /* f.root-servers.net */
{ "192.112.36.4", AF_INET }, /* g.root-servers.net */
{ "2001:500:12::d0d", AF_INET6 }, /* g.root-servers.net */
{ "198.97.190.53", AF_INET }, /* h.root-servers.net */
{ "2001:500:1::53", AF_INET6 }, /* h.root-servers.net */
{ "192.36.148.17", AF_INET }, /* i.root-servers.net */
{ "2001:7fe::53", AF_INET6 }, /* i.root-servers.net */
{ "192.58.128.30", AF_INET }, /* j.root-servers.net */
{ "2001:503:c27::2:30", AF_INET6 }, /* j.root-servers.net */
{ "193.0.14.129", AF_INET }, /* k.root-servers.net */
{ "2001:7fd::1", AF_INET6 }, /* k.root-servers.net */
{ "199.7.83.42", AF_INET }, /* l.root-servers.net */
{ "2001:500:9f::42", AF_INET6 }, /* l.root-servers.net */
{ "202.12.27.33", AF_INET }, /* m.root-servers.net */
{ "2001:dc3::35", AF_INET6 } /* m.root-servers.net */
};
/*%
* Exit Codes:
*
*\li 0 Everything went well, including things like NXDOMAIN
*\li 1 Usage error
*\li 7 Got too many RR's or Names
*\li 8 Couldn't open batch file
*\li 9 No reply from server
*\li 10 Internal error
*/
int exitcode = 0;
int fatalexit = 0;
char keynametext[MXNAME];
char keyfile[MXNAME] = "";
char keysecret[MXNAME] = "";
unsigned char cookie_secret[33];
unsigned char cookie[8];
dns_name_t *hmacname = NULL;
unsigned int digestbits = 0;
isc_buffer_t *namebuf = NULL;
dns_tsigkey_t *tsigkey = NULL;
int validated = 1;
int debugging = 0;
int debugtiming = 0;
char *progname = NULL;
dig_lookup_t *current_lookup = NULL;
#define DIG_MAX_ADDRESSES 20
/* dynamic callbacks */
isc_result_t
(*dighost_printmessage)(dig_query_t *query, dns_message_t *msg,
int headers);
void
(*dighost_received)(unsigned int bytes, struct sockaddr_storage *from, dig_query_t *query);
void
(*dighost_trying)(char *frm, dig_lookup_t *lookup);
void
(*dighost_shutdown)(void);
/* forward declarations */
static void
cancel_lookup(dig_lookup_t *lookup);
static void
recv_done(isc_task_t *task, isc_event_t *event);
static void
send_udp(dig_query_t *query);
static void
connect_timeout(isc_task_t *task, isc_event_t *event);
static void
launch_next_query(dig_query_t *query, int include_question);
static void
check_next_lookup(dig_lookup_t *lookup);
static int
next_origin(dig_lookup_t *oldlookup);
char *
next_token(char **stringp, const char *delim) {
char *res;
do {
res = strsep(stringp, delim);
if (res == NULL)
break;
} while (*res == '\0');
return (res);
}
static int
count_dots(char *string) {
char *s;
int i = 0;
s = string;
while (*s != '\0') {
if (*s == '.')
i++;
s++;
}
return (i);
}
static void
hex_dump(isc_buffer_t *b) {
unsigned int len, i;
isc_region_t r;
isc_buffer_usedregion(b, &r);
printf("%u bytes\n", r.length);
for (len = 0; len < r.length; len++) {
printf("%02x ", r.base[len]);
if (len % 16 == 15) {
fputs(" ", stdout);
for (i = len - 15; i <= len; i++) {
if (r.base[i] >= '!' && r.base[i] <= '}')
putchar(r.base[i]);
else
putchar('.');
}
printf("\n");
}
}
if (len % 16 != 0) {
for (i = len; (i % 16) != 0; i++)
fputs(" ", stdout);
fputs(" ", stdout);
for (i = ((len>>4)<<4); i < len; i++) {
if (r.base[i] >= '!' && r.base[i] <= '}')
putchar(r.base[i]);
else
putchar('.');
}
printf("\n");
}
}
/*%
* Append 'len' bytes of 'text' at '*p', failing with
* ISC_R_NOSPACE if that would advance p past 'end'.
*/
static isc_result_t
append(const char *text, size_t len, char **p, char *end) {
if (*p + len > end)
return (ISC_R_NOSPACE);
memmove(*p, text, len);
*p += len;
return (ISC_R_SUCCESS);
}
static isc_result_t
reverse_octets(const char *in, char **p, char *end) {
const char *dot = strchr(in, '.');
size_t len;
if (dot != NULL) {
isc_result_t result;
result = reverse_octets(dot + 1, p, end);
if (result != ISC_R_SUCCESS)
return (result);
result = append(".", 1, p, end);
if (result != ISC_R_SUCCESS)
return (result);
len = (int) (dot - in);
} else {
len = (int) strlen(in);
}
return (append(in, len, p, end));
}
isc_result_t
get_reverse(char *reverse, size_t len, char *value, int ip6_int,
int strict)
{
int r;
struct in_addr in;
struct in6_addr in6;
isc_result_t result;
r = inet_pton(AF_INET6, value, &in6);
if (r > 0) {
/* This is a valid IPv6 address. */
static char hex_digits[] = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
int i;
unsigned char *bytes = (unsigned char *)&in6;
char* cp;
if (len <= 15 * 4 + sizeof("ip6.int"))
return (ISC_R_NOMEMORY);
cp = reverse;
for (i = 15; i >= 0; i--) {
*cp++ = hex_digits[bytes[i] & 0x0f];
*cp++ = '.';
*cp++ = hex_digits[(bytes[i] >> 4) & 0x0f];
*cp++ = '.';
}
*cp = '\0';
if (strlcat(reverse, ip6_int ? "ip6.int" : "ip6.arpa", len)
>= len)
return (ISC_R_NOSPACE);
return (ISC_R_SUCCESS);
} else {
/*
* Not a valid IPv6 address. Assume IPv4.
* If 'strict' is not set, construct the
* in-addr.arpa name by blindly reversing
* octets whether or not they look like integers,
* so that this can be used for RFC2317 names
* and such.
*/
char *p = reverse;
char *end = reverse + len;
if (strict && inet_pton(AF_INET, value, &in) != 1)
return (DNS_R_BADDOTTEDQUAD);
result = reverse_octets(value, &p, end);
if (result != ISC_R_SUCCESS)
return (result);
/* Append .in-addr.arpa. and a terminating NUL. */
result = append(".in-addr.arpa.", 15, &p, end);
return (result);
}
}
void
fatal(const char *format, ...) {
va_list args;
fflush(stdout);
fprintf(stderr, "%s: ", progname);
va_start(args, format);
vfprintf(stderr, format, args);
va_end(args);
fprintf(stderr, "\n");
if (exitcode < 10)
exitcode = 10;
if (fatalexit != 0)
exitcode = fatalexit;
exit(exitcode);
}
void
debug(const char *format, ...) {
va_list args;
struct timespec t;
if (debugging) {
fflush(stdout);
if (debugtiming) {
clock_gettime(CLOCK_MONOTONIC, &t);
fprintf(stderr, "%lld.%06ld: ", t.tv_sec, t.tv_nsec /
1000);
}
va_start(args, format);
vfprintf(stderr, format, args);
va_end(args);
fprintf(stderr, "\n");
}
}
void
check_result(isc_result_t result, const char *msg) {
if (result != ISC_R_SUCCESS) {
fatal("%s: %s", msg, isc_result_totext(result));
}
}
/*%
* Create a server structure, which is part of the lookup structure.
* This is little more than a linked list of servers to query in hopes
* of finding the answer the user is looking for
*/
dig_server_t *
make_server(const char *servname, const char *userarg) {
dig_server_t *srv;
REQUIRE(servname != NULL);
debug("make_server(%s)", servname);
srv = malloc(sizeof(struct dig_server));
if (srv == NULL)
fatal("memory allocation failure in %s:%d",
__FILE__, __LINE__);
strlcpy(srv->servername, servname, MXNAME);
strlcpy(srv->userarg, userarg, MXNAME);
ISC_LINK_INIT(srv, link);
return (srv);
}
static int
addr2af(int lwresaddrtype)
{
int af = 0;
switch (lwresaddrtype) {
case LWRES_ADDRTYPE_V4:
af = AF_INET;
break;
case LWRES_ADDRTYPE_V6:
af = AF_INET6;
break;
}
return (af);
}
/*%
* Create a copy of the server list from the lwres configuration structure.
* The dest list must have already had ISC_LIST_INIT applied.
*/
static void
copy_server_list(lwres_conf_t *confdata, dig_serverlist_t *dest) {
dig_server_t *newsrv;
char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255") +
sizeof("%4000000000")];
int af;
int i;
debug("copy_server_list()");
for (i = 0; i < confdata->nsnext; i++) {
af = addr2af(confdata->nameservers[i].family);
if (af == AF_INET && !have_ipv4)
continue;
if (af == AF_INET6 && !have_ipv6)
continue;
inet_ntop(af, confdata->nameservers[i].address,
tmp, sizeof(tmp));
if (af == AF_INET6 && confdata->nameservers[i].zone != 0) {
char buf[sizeof("%4000000000")];
snprintf(buf, sizeof(buf), "%%%u",
confdata->nameservers[i].zone);
strlcat(tmp, buf, sizeof(tmp));
}
newsrv = make_server(tmp, tmp);
ISC_LINK_INIT(newsrv, link);
ISC_LIST_ENQUEUE(*dest, newsrv, link);
}
}
void
flush_server_list(void) {
dig_server_t *s, *ps;
debug("flush_server_list()");
s = ISC_LIST_HEAD(server_list);
while (s != NULL) {
ps = s;
s = ISC_LIST_NEXT(s, link);
ISC_LIST_DEQUEUE(server_list, ps, link);
free(ps);
}
}
/* this used to be bind9_getaddresses from lib/bind9 */
static isc_result_t
get_addresses(const char *hostname, in_port_t dstport,
struct sockaddr_storage *addrs, int addrsize, int *addrcount)
{
struct addrinfo *ai = NULL, *tmpai, hints;
int result, i;
char dport[sizeof("65535")];
REQUIRE(hostname != NULL);
REQUIRE(addrs != NULL);
REQUIRE(addrcount != NULL);
REQUIRE(addrsize > 0);
memset(&hints, 0, sizeof(hints));
if (!have_ipv6)
hints.ai_family = PF_INET;
else if (!have_ipv4)
hints.ai_family = PF_INET6;
else {
hints.ai_family = PF_UNSPEC;
hints.ai_flags = AI_ADDRCONFIG;
}
hints.ai_socktype = SOCK_DGRAM;
snprintf(dport, sizeof(dport), "%d", dstport);
result = getaddrinfo(hostname, dport, &hints, &ai);
switch (result) {
case 0:
break;
case EAI_NONAME:
case EAI_NODATA:
return (ISC_R_NOTFOUND);
default:
return (ISC_R_FAILURE);
}
for (tmpai = ai, i = 0;
tmpai != NULL && i < addrsize;
tmpai = tmpai->ai_next)
{
if (tmpai->ai_family != AF_INET &&
tmpai->ai_family != AF_INET6)
continue;
if (tmpai->ai_addrlen > sizeof(addrs[i]))
continue;
memset(&addrs[i], 0, sizeof(addrs[i]));
memcpy(&addrs[i], tmpai->ai_addr, tmpai->ai_addrlen);
i++;
}
freeaddrinfo(ai);
*addrcount = i;
if (*addrcount == 0)
return (ISC_R_NOTFOUND);
else
return (ISC_R_SUCCESS);
}
isc_result_t
set_nameserver(char *opt) {
isc_result_t result;
struct sockaddr_storage sockaddrs[DIG_MAX_ADDRESSES];
int count, i;
dig_server_t *srv;
char tmp[NI_MAXHOST];
if (opt == NULL)
return ISC_R_NOTFOUND;
result = get_addresses(opt, 0, sockaddrs,
DIG_MAX_ADDRESSES, &count);
if (result != ISC_R_SUCCESS)
return (result);
flush_server_list();
for (i = 0; i < count; i++) {
int error;
error = getnameinfo((struct sockaddr *)&sockaddrs[i],
sockaddrs[i].ss_len, tmp, sizeof(tmp), NULL, 0,
NI_NUMERICHOST | NI_NUMERICSERV);
if (error)
fatal("%s", gai_strerror(error));
srv = make_server(tmp, opt);
if (srv == NULL)
fatal("memory allocation failure");
ISC_LIST_APPEND(server_list, srv, link);
}
return (ISC_R_SUCCESS);
}
static isc_result_t
add_nameserver(lwres_conf_t *confdata, const char *addr, int af) {
int i = confdata->nsnext;
if (confdata->nsnext >= LWRES_CONFMAXNAMESERVERS)
return (ISC_R_FAILURE);
switch (af) {
case AF_INET:
confdata->nameservers[i].family = LWRES_ADDRTYPE_V4;
confdata->nameservers[i].length = sizeof(struct in_addr);
break;
case AF_INET6:
confdata->nameservers[i].family = LWRES_ADDRTYPE_V6;
confdata->nameservers[i].length = sizeof(struct in6_addr);
break;
default:
return (ISC_R_FAILURE);
}
if (inet_pton(af, addr, &confdata->nameservers[i].address) == 1) {
confdata->nsnext++;
return (ISC_R_SUCCESS);
}
return (ISC_R_FAILURE);
}
/*%
* Produce a cloned server list. The dest list must have already had
* ISC_LIST_INIT applied.
*/
void
clone_server_list(dig_serverlist_t src, dig_serverlist_t *dest) {
dig_server_t *srv, *newsrv;
debug("clone_server_list()");
srv = ISC_LIST_HEAD(src);
while (srv != NULL) {
newsrv = make_server(srv->servername, srv->userarg);
ISC_LINK_INIT(newsrv, link);
ISC_LIST_ENQUEUE(*dest, newsrv, link);
srv = ISC_LIST_NEXT(srv, link);
}
}
/*%
* Create an empty lookup structure, which holds all the information needed
* to get an answer to a user's question. This structure contains two
* linked lists: the server list (servers to query) and the query list
* (outstanding queries which have been made to the listed servers).
*/
dig_lookup_t *
make_empty_lookup(void) {
dig_lookup_t *looknew;
debug("make_empty_lookup()");
INSIST(!free_now);
looknew = malloc(sizeof(struct dig_lookup));
if (looknew == NULL)
fatal("memory allocation failure in %s:%d",
__FILE__, __LINE__);
looknew->pending = 1;
looknew->textname[0] = 0;
looknew->cmdline[0] = 0;
looknew->rdtype = dns_rdatatype_a;
looknew->qrdtype = dns_rdatatype_a;
looknew->rdclass = dns_rdataclass_in;
looknew->rdtypeset = 0;
looknew->rdclassset = 0;
looknew->sendspace = NULL;
looknew->sendmsg = NULL;
looknew->name = NULL;
looknew->oname = NULL;
looknew->xfr_q = NULL;
looknew->current_query = NULL;
looknew->doing_xfr = 0;
looknew->ixfr_serial = 0;
looknew->trace = 0;
looknew->trace_root = 0;
looknew->identify = 0;
looknew->identify_previous_line = 0;
looknew->ignore = 0;
looknew->servfail_stops = 1;
looknew->besteffort = 1;
looknew->dnssec = 0;
looknew->ednsflags = 0;
looknew->opcode = dns_opcode_query;
looknew->expire = 0;
looknew->nsid = 0;
looknew->idnout = 0;
looknew->sit = 0;
looknew->udpsize = 0;
looknew->edns = -1;
looknew->recurse = 1;
looknew->aaonly = 0;
looknew->adflag = 0;
looknew->cdflag = 0;
looknew->ns_search_only = 0;
looknew->origin = NULL;
looknew->tsigctx = NULL;
looknew->querysig = NULL;
looknew->retries = tries;
looknew->nsfound = 0;
looknew->tcp_mode = 0;
looknew->tcp_mode_set = 0;
looknew->ip6_int = 0;
looknew->comments = 1;
looknew->stats = 1;
looknew->section_question = 1;
looknew->section_answer = 1;
looknew->section_authority = 1;
looknew->section_additional = 1;
looknew->new_search = 0;
looknew->done_as_is = 0;
looknew->need_search = 0;
looknew->ecs_addr = NULL;
looknew->ecs_plen = 0;
looknew->sitvalue = NULL;
looknew->ednsopts = NULL;
looknew->ednsoptscnt = 0;
looknew->ednsneg = 0;
looknew->eoferr = 0;
dns_fixedname_init(&looknew->fdomain);
ISC_LINK_INIT(looknew, link);
ISC_LIST_INIT(looknew->q);
ISC_LIST_INIT(looknew->connecting);
ISC_LIST_INIT(looknew->my_server_list);
return (looknew);
}
#define EDNSOPT_OPTIONS 100U
static void
cloneopts(dig_lookup_t *looknew, dig_lookup_t *lookold) {
size_t len = sizeof(looknew->ednsopts[0]) * EDNSOPT_OPTIONS;
size_t i;
looknew->ednsopts = malloc(len);
if (looknew->ednsopts == NULL)
fatal("out of memory");
for (i = 0; i < EDNSOPT_OPTIONS; i++) {
looknew->ednsopts[i].code = 0;
looknew->ednsopts[i].length = 0;
looknew->ednsopts[i].value = NULL;
}
looknew->ednsoptscnt = 0;
if (lookold == NULL || lookold->ednsopts == NULL)
return;
for (i = 0; i < lookold->ednsoptscnt; i++) {
len = lookold->ednsopts[i].length;
if (len != 0) {
INSIST(lookold->ednsopts[i].value != NULL);
looknew->ednsopts[i].value =
malloc(len);
if (looknew->ednsopts[i].value == NULL)
fatal("out of memory");
memmove(looknew->ednsopts[i].value,
lookold->ednsopts[i].value, len);
}
looknew->ednsopts[i].code = lookold->ednsopts[i].code;
looknew->ednsopts[i].length = len;
}
looknew->ednsoptscnt = lookold->ednsoptscnt;
}
/*%
* Clone a lookup, perhaps copying the server list. This does not clone
* the query list, since it will be regenerated by the setup_lookup()
* function, nor does it queue up the new lookup for processing.
* Caution: If you don't clone the servers, you MUST clone the server
* list separately from somewhere else, or construct it by hand.
*/
dig_lookup_t *
clone_lookup(dig_lookup_t *lookold, int servers) {
dig_lookup_t *looknew;
debug("clone_lookup()");
INSIST(!free_now);
looknew = make_empty_lookup();
INSIST(looknew != NULL);
strlcpy(looknew->textname, lookold->textname, MXNAME);
strlcpy(looknew->cmdline, lookold->cmdline, MXNAME);
looknew->textname[MXNAME-1] = 0;
looknew->rdtype = lookold->rdtype;
looknew->qrdtype = lookold->qrdtype;
looknew->rdclass = lookold->rdclass;
looknew->rdtypeset = lookold->rdtypeset;
looknew->rdclassset = lookold->rdclassset;
looknew->doing_xfr = lookold->doing_xfr;
looknew->ixfr_serial = lookold->ixfr_serial;
looknew->trace = lookold->trace;
looknew->trace_root = lookold->trace_root;
looknew->identify = lookold->identify;
looknew->identify_previous_line = lookold->identify_previous_line;
looknew->ignore = lookold->ignore;
looknew->servfail_stops = lookold->servfail_stops;
looknew->besteffort = lookold->besteffort;
looknew->dnssec = lookold->dnssec;
looknew->ednsflags = lookold->ednsflags;
looknew->opcode = lookold->opcode;
looknew->expire = lookold->expire;
looknew->nsid = lookold->nsid;
looknew->sit = lookold->sit;
looknew->sitvalue = lookold->sitvalue;
if (lookold->ednsopts != NULL) {
cloneopts(looknew, lookold);
} else {
looknew->ednsopts = NULL;
looknew->ednsoptscnt = 0;
}
looknew->ednsneg = lookold->ednsneg;
looknew->idnout = lookold->idnout;
looknew->udpsize = lookold->udpsize;
looknew->edns = lookold->edns;
looknew->recurse = lookold->recurse;
looknew->aaonly = lookold->aaonly;
looknew->adflag = lookold->adflag;
looknew->cdflag = lookold->cdflag;
looknew->ns_search_only = lookold->ns_search_only;
looknew->tcp_mode = lookold->tcp_mode;
looknew->tcp_mode_set = lookold->tcp_mode_set;
looknew->comments = lookold->comments;
looknew->stats = lookold->stats;
looknew->section_question = lookold->section_question;
looknew->section_answer = lookold->section_answer;
looknew->section_authority = lookold->section_authority;
looknew->section_additional = lookold->section_additional;
looknew->origin = lookold->origin;
looknew->retries = lookold->retries;
looknew->tsigctx = NULL;
looknew->need_search = lookold->need_search;
looknew->done_as_is = lookold->done_as_is;
looknew->eoferr = lookold->eoferr;
if (lookold->ecs_addr != NULL) {
size_t len = sizeof(struct sockaddr_storage);
looknew->ecs_addr = malloc(len);
if (looknew->ecs_addr == NULL)
fatal("out of memory");
memmove(looknew->ecs_addr, lookold->ecs_addr, len);
looknew->ecs_plen = lookold->ecs_plen;
}
dns_name_copy(dns_fixedname_name(&lookold->fdomain),
dns_fixedname_name(&looknew->fdomain), NULL);
if (servers)
clone_server_list(lookold->my_server_list,
&looknew->my_server_list);
return (looknew);
}
/*%
* Requeue a lookup for further processing, perhaps copying the server
* list. The new lookup structure is returned to the caller, and is
* queued for processing. If servers are not cloned in the requeue, they
* must be added before allowing the current event to complete, since the
* completion of the event may result in the next entry on the lookup
* queue getting run.
*/
dig_lookup_t *
requeue_lookup(dig_lookup_t *lookold, int servers) {
dig_lookup_t *looknew;
debug("requeue_lookup()");
lookup_counter++;
if (lookup_counter > LOOKUP_LIMIT)
fatal("too many lookups");
looknew = clone_lookup(lookold, servers);
INSIST(looknew != NULL);
debug("before insertion, init@%p -> %p, new@%p -> %p",
lookold, lookold->link.next, looknew, looknew->link.next);
ISC_LIST_PREPEND(lookup_list, looknew, link);
debug("after insertion, init -> %p, new = %p, new -> %p",
lookold, looknew, looknew->link.next);
return (looknew);
}
void
setup_text_key(void) {
isc_result_t result;
dns_name_t keyname;
isc_buffer_t secretbuf;
unsigned int secretsize;
unsigned char *secretstore;
debug("setup_text_key()");
result = isc_buffer_allocate(&namebuf, MXNAME);
check_result(result, "isc_buffer_allocate");
dns_name_init(&keyname, NULL);
check_result(result, "dns_name_init");
isc_buffer_putstr(namebuf, keynametext);
secretsize = (unsigned int) strlen(keysecret) * 3 / 4;
secretstore = malloc(secretsize);
if (secretstore == NULL)
fatal("memory allocation failure in %s:%d",
__FILE__, __LINE__);
isc_buffer_init(&secretbuf, secretstore, secretsize);
result = isc_base64_decodestring(keysecret, &secretbuf);
if (result != ISC_R_SUCCESS)
goto failure;
secretsize = isc_buffer_usedlength(&secretbuf);
if (hmacname == NULL) {
result = DST_R_UNSUPPORTEDALG;
goto failure;
}
result = dns_name_fromtext(&keyname, namebuf, dns_rootname, 0, namebuf);
if (result != ISC_R_SUCCESS)
goto failure;
result = dns_tsigkey_create(&keyname, hmacname, secretstore,
(int)secretsize, 0, NULL, 0, 0,
&tsigkey);
failure:
if (result != ISC_R_SUCCESS)
printf(";; Couldn't create key %s: %s\n",
keynametext, isc_result_totext(result));
else
dst_key_setbits(tsigkey->key, digestbits);
free(secretstore);
dns_name_invalidate(&keyname);
isc_buffer_free(&namebuf);
}
static uint32_t
parse_bits(char *arg, uint32_t max) {
uint32_t tmp;
const char *errstr;
tmp = strtonum(arg, 0, max, &errstr);
if (errstr != NULL)
fatal("digest bits is %s: '%s'", errstr, arg);
tmp = (tmp + 7) & ~0x7U;
return (tmp);
}
isc_result_t
parse_netprefix(struct sockaddr_storage **sap, int *plen, const char *value) {
struct sockaddr_storage *sa = NULL;
struct in_addr *in4;
struct in6_addr *in6;
int prefix_length;
REQUIRE(sap != NULL && *sap == NULL);
sa = calloc(1, sizeof(*sa));
if (sa == NULL)
fatal("out of memory");
in4 = &((struct sockaddr_in *)sa)->sin_addr;
in6 = &((struct sockaddr_in6 *)sa)->sin6_addr;
if (strcmp(value, "0") == 0) {
sa->ss_family = AF_UNSPEC;
prefix_length = 0;
goto done;
}
if ((prefix_length = inet_net_pton(AF_INET6, value, in6, sizeof(*in6)))
!= -1) {
sa->ss_len = sizeof(struct sockaddr_in6);
sa->ss_family = AF_INET6;
} else if ((prefix_length = inet_net_pton(AF_INET, value, in4,
sizeof(*in4))) != -1) {
sa->ss_len = sizeof(struct sockaddr_in);
sa->ss_family = AF_INET;
} else
fatal("invalid address '%s'", value);
done:
*plen = prefix_length;
*sap = sa;
return (ISC_R_SUCCESS);
}
/*
* Parse HMAC algorithm specification
*/
void
parse_hmac(const char *hmac) {
char buf[20];
size_t len;
REQUIRE(hmac != NULL);
len = strlen(hmac);
if (len >= sizeof(buf))
fatal("unknown key type '%.*s'", (int)len, hmac);
strlcpy(buf, hmac, sizeof(buf));
digestbits = 0;
if (strcasecmp(buf, "hmac-sha1") == 0) {
hmacname = DNS_TSIG_HMACSHA1_NAME;
digestbits = 0;
} else if (strncasecmp(buf, "hmac-sha1-", 10) == 0) {
hmacname = DNS_TSIG_HMACSHA1_NAME;
digestbits = parse_bits(&buf[10], 160);
} else if (strcasecmp(buf, "hmac-sha224") == 0) {
hmacname = DNS_TSIG_HMACSHA224_NAME;
} else if (strncasecmp(buf, "hmac-sha224-", 12) == 0) {
hmacname = DNS_TSIG_HMACSHA224_NAME;
digestbits = parse_bits(&buf[12], 224);
} else if (strcasecmp(buf, "hmac-sha256") == 0) {
hmacname = DNS_TSIG_HMACSHA256_NAME;
} else if (strncasecmp(buf, "hmac-sha256-", 12) == 0) {
hmacname = DNS_TSIG_HMACSHA256_NAME;
digestbits = parse_bits(&buf[12], 256);
} else if (strcasecmp(buf, "hmac-sha384") == 0) {
hmacname = DNS_TSIG_HMACSHA384_NAME;
} else if (strncasecmp(buf, "hmac-sha384-", 12) == 0) {
hmacname = DNS_TSIG_HMACSHA384_NAME;
digestbits = parse_bits(&buf[12], 384);
} else if (strcasecmp(buf, "hmac-sha512") == 0) {
hmacname = DNS_TSIG_HMACSHA512_NAME;
} else if (strncasecmp(buf, "hmac-sha512-", 12) == 0) {
hmacname = DNS_TSIG_HMACSHA512_NAME;
digestbits = parse_bits(&buf[12], 512);
} else {
fprintf(stderr, ";; Warning, ignoring "
"invalid TSIG algorithm %s\n", buf);
}
}
/*
* Get a key from a named.conf format keyfile
*/
static isc_result_t
read_confkey(void) {
cfg_parser_t *pctx = NULL;
cfg_obj_t *file = NULL;
const cfg_obj_t *keyobj = NULL;
const cfg_obj_t *secretobj = NULL;
const cfg_obj_t *algorithmobj = NULL;
const char *keyname;
const char *secretstr;
const char *algorithm;
isc_result_t result;
result = cfg_parser_create(NULL, &pctx);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = cfg_parse_file(pctx, keyfile, &cfg_type_sessionkey,
&file);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = cfg_map_get(file, "key", &keyobj);
if (result != ISC_R_SUCCESS)
goto cleanup;
(void) cfg_map_get(keyobj, "secret", &secretobj);
(void) cfg_map_get(keyobj, "algorithm", &algorithmobj);
if (secretobj == NULL || algorithmobj == NULL)
fatal("key must have algorithm and secret");
keyname = cfg_obj_asstring(cfg_map_getname(keyobj));
secretstr = cfg_obj_asstring(secretobj);
algorithm = cfg_obj_asstring(algorithmobj);
strlcpy(keynametext, keyname, sizeof(keynametext));
strlcpy(keysecret, secretstr, sizeof(keysecret));
parse_hmac(algorithm);
setup_text_key();
cleanup:
if (pctx != NULL) {
if (file != NULL)
cfg_obj_destroy(pctx, &file);
cfg_parser_destroy(&pctx);
}
return (result);
}
void
setup_file_key(void) {
isc_result_t result;
debug("setup_file_key()");
/* Try reading the key as a session.key keyfile */
result = read_confkey();
if (result != ISC_R_SUCCESS)
fprintf(stderr, "Couldn't read key from %s: %s\n",
keyfile, isc_result_totext(result));
}
static dig_searchlist_t *
make_searchlist_entry(char *domain) {
dig_searchlist_t *search;
search = malloc(sizeof(*search));
if (search == NULL)
fatal("memory allocation failure in %s:%d",
__FILE__, __LINE__);
strlcpy(search->origin, domain, MXNAME);
search->origin[MXNAME-1] = 0;
ISC_LINK_INIT(search, link);
return (search);
}
static void
clear_searchlist(void) {
dig_searchlist_t *search;
while ((search = ISC_LIST_HEAD(search_list)) != NULL) {
ISC_LIST_UNLINK(search_list, search, link);
free(search);
}
}
static void
create_search_list(lwres_conf_t *confdata) {
int i;
dig_searchlist_t *search;
debug("create_search_list()");
clear_searchlist();
for (i = 0; i < confdata->searchnxt; i++) {
search = make_searchlist_entry(confdata->search[i]);
ISC_LIST_APPEND(search_list, search, link);
}
}
/*%
* Setup the system as a whole, reading key information and resolv.conf
* settings.
*/
void
setup_system(int ipv4only, int ipv6only) {
dig_searchlist_t *domain = NULL;
lwres_result_t lwresult;
int lwresflags = 0;
debug("setup_system()");
if (ipv4only) {
if (have_ipv4)
have_ipv6 = 0;
else
fatal("can't find IPv4 networking");
}
if (ipv6only) {
if (have_ipv6)
have_ipv4 = 0;
else
fatal("can't find IPv6 networking");
}
if (have_ipv4)
lwresflags |= LWRES_USEIPV4;
if (have_ipv6)
lwresflags |= LWRES_USEIPV6;
lwres_conf_init(lwconf, lwresflags);
lwresult = lwres_conf_parse(lwconf, _PATH_RESCONF);
if (lwresult != LWRES_R_SUCCESS && lwresult != LWRES_R_NOTFOUND)
fatal("parse of %s failed", _PATH_RESCONF);
/* Make the search list */
if (lwconf->searchnxt > 0)
create_search_list(lwconf);
else { /* No search list. Use the domain name if any */
if (lwconf->domainname != NULL) {
domain = make_searchlist_entry(lwconf->domainname);
ISC_LIST_APPEND(search_list, domain, link);
domain = NULL;
}
}
if (ndots == -1) {
ndots = lwconf->ndots;
debug("ndots is %d.", ndots);
}
/* If user doesn't specify server use nameservers from resolv.conf. */
if (ISC_LIST_EMPTY(server_list))
copy_server_list(lwconf, &server_list);
/* If we don't find a nameserver fall back to localhost */
if (ISC_LIST_EMPTY(server_list)) {
if (have_ipv4) {
lwresult = add_nameserver(lwconf, "127.0.0.1", AF_INET);
if (lwresult != ISC_R_SUCCESS)
fatal("add_nameserver failed");
}
if (have_ipv6) {
lwresult = add_nameserver(lwconf, "::1", AF_INET6);
if (lwresult != ISC_R_SUCCESS)
fatal("add_nameserver failed");
}
copy_server_list(lwconf, &server_list);
}
if (keyfile[0] != 0)
setup_file_key();
else if (keysecret[0] != 0)
setup_text_key();
arc4random_buf(cookie_secret, sizeof(cookie_secret));
}
/*%
* Override the search list derived from resolv.conf by 'domain'.
*/
void
set_search_domain(char *domain) {
dig_searchlist_t *search;
clear_searchlist();
search = make_searchlist_entry(domain);
ISC_LIST_APPEND(search_list, search, link);
}
/*%
* Setup the ISC and DNS libraries for use by the system.
*/
void
setup_libs(void) {
isc_result_t result;
isc_logconfig_t *logconfig = NULL;
debug("setup_libs()");
dns_result_register();
result = isc_log_create(&lctx, &logconfig);
check_result(result, "isc_log_create");
isc_log_setcontext(lctx);
dns_log_init(lctx);
dns_log_setcontext(lctx);
result = isc_log_usechannel(logconfig, "default_debug", NULL, NULL);
check_result(result, "isc_log_usechannel");
isc_log_setdebuglevel(lctx, 0);
result = isc_taskmgr_create(1, 0, &taskmgr);
check_result(result, "isc_taskmgr_create");
result = isc_task_create(taskmgr, 0, &global_task);
check_result(result, "isc_task_create");
isc_task_setname(global_task, "dig", NULL);
result = isc_timermgr_create(&timermgr);
check_result(result, "isc_timermgr_create");
result = isc_socketmgr_create(&socketmgr);
check_result(result, "isc_socketmgr_create");
check_result(result, "isc_entropy_create");
result = dst_lib_init();
check_result(result, "dst_lib_init");
is_dst_up = 1;
}
typedef struct dig_ednsoptname {
uint32_t code;
const char *name;
} dig_ednsoptname_t;
dig_ednsoptname_t optnames[] = {
{ 3, "NSID" }, /* RFC 5001 */
{ 5, "DAU" }, /* RFC 6975 */
{ 6, "DHU" }, /* RFC 6975 */
{ 7, "N3U" }, /* RFC 6975 */
{ 8, "ECS" }, /* RFC 7871 */
{ 9, "EXPIRE" }, /* RFC 7314 */
{ 10, "COOKIE" }, /* RFC 7873 */
{ 11, "KEEPALIVE" }, /* RFC 7828 */
{ 12, "PADDING" }, /* RFC 7830 */
{ 12, "PAD" }, /* shorthand */
{ 13, "CHAIN" }, /* RFC 7901 */
{ 14, "KEY-TAG" }, /* RFC 8145 */
{ 26946, "DEVICEID" }, /* Brian Hartvigsen */
};
#define N_EDNS_OPTNAMES (sizeof(optnames) / sizeof(optnames[0]))
void
save_opt(dig_lookup_t *lookup, char *code, char *value) {
isc_result_t result;
uint32_t num = 0;
isc_buffer_t b;
int found = 0;
unsigned int i;
const char *errstr;
if (lookup->ednsoptscnt >= EDNSOPT_OPTIONS)
fatal("too many ednsopts");
for (i = 0; i < N_EDNS_OPTNAMES; i++) {
if (strcasecmp(code, optnames[i].name) == 0) {
num = optnames[i].code;
found = 1;
break;
}
}
if (!found) {
num = strtonum(code, 0, 65535, &errstr);
if (errstr != NULL)
fatal("edns code point is %s: '%s'", errstr, code);
}
if (lookup->ednsopts == NULL) {
cloneopts(lookup, NULL);
}
if (lookup->ednsopts[lookup->ednsoptscnt].value != NULL)
free(lookup->ednsopts[lookup->ednsoptscnt].value);
lookup->ednsopts[lookup->ednsoptscnt].code = num;
lookup->ednsopts[lookup->ednsoptscnt].length = 0;
lookup->ednsopts[lookup->ednsoptscnt].value = NULL;
if (value != NULL) {
char *buf;
buf = malloc(strlen(value)/2 + 1);
if (buf == NULL)
fatal("out of memory");
isc_buffer_init(&b, buf, (unsigned int) strlen(value)/2 + 1);
result = isc_hex_decodestring(value, &b);
check_result(result, "isc_hex_decodestring");
lookup->ednsopts[lookup->ednsoptscnt].value =
isc_buffer_base(&b);
lookup->ednsopts[lookup->ednsoptscnt].length =
isc_buffer_usedlength(&b);
}
lookup->ednsoptscnt++;
}
/*%
* Add EDNS0 option record to a message. Currently, the only supported
* options are UDP buffer size, the DO bit, and EDNS options
* (e.g., NSID, SIT, client-subnet)
*/
static void
add_opt(dns_message_t *msg, uint16_t udpsize, uint16_t edns,
unsigned int flags, dns_ednsopt_t *opts, size_t count)
{
dns_rdataset_t *rdataset = NULL;
isc_result_t result;
debug("add_opt()");
result = dns_message_buildopt(msg, &rdataset, edns, udpsize, flags,
opts, count);
check_result(result, "dns_message_buildopt");
result = dns_message_setopt(msg, rdataset);
check_result(result, "dns_message_setopt");
}
/*%
* Add a question section to a message, asking for the specified name,
* type, and class.
*/
static void
add_question(dns_message_t *message, dns_name_t *name,
dns_rdataclass_t rdclass, dns_rdatatype_t rdtype)
{
dns_rdataset_t *rdataset;
isc_result_t result;
debug("add_question()");
rdataset = NULL;
result = dns_message_gettemprdataset(message, &rdataset);
check_result(result, "dns_message_gettemprdataset()");
dns_rdataset_makequestion(rdataset, rdclass, rdtype);
ISC_LIST_APPEND(name->list, rdataset, link);
}
/*%
* Check if we're done with all the queued lookups, which is true iff
* all sockets, sends, and recvs are accounted for (counters == 0),
* and the lookup list is empty.
* If we are done, pass control back out to dighost_shutdown() (which is
* part of dig.c, host.c, or nslookup.c) to either shutdown the system as
* a whole or reseed the lookup list.
*/
static void
check_if_done(void) {
debug("check_if_done()");
debug("list %s", ISC_LIST_EMPTY(lookup_list) ? "empty" : "full");
if (ISC_LIST_EMPTY(lookup_list) && current_lookup == NULL &&
sendcount == 0) {
INSIST(sockcount == 0);
INSIST(recvcount == 0);
debug("shutting down");
dighost_shutdown();
}
}
/*%
* Clear out a query when we're done with it. WARNING: This routine
* WILL invalidate the query pointer.
*/
static void
clear_query(dig_query_t *query) {
dig_lookup_t *lookup;
REQUIRE(query != NULL);
debug("clear_query(%p)", query);
if (query->timer != NULL)
isc_timer_detach(&query->timer);
lookup = query->lookup;
if (lookup->current_query == query)
lookup->current_query = NULL;
if (ISC_LINK_LINKED(query, link))
ISC_LIST_UNLINK(lookup->q, query, link);
if (ISC_LINK_LINKED(query, clink))
ISC_LIST_UNLINK(lookup->connecting, query, clink);
if (ISC_LINK_LINKED(&query->recvbuf, link))
ISC_LIST_DEQUEUE(query->recvlist, &query->recvbuf,
link);
if (ISC_LINK_LINKED(&query->lengthbuf, link))
ISC_LIST_DEQUEUE(query->lengthlist, &query->lengthbuf,
link);
INSIST(query->recvspace != NULL);
if (query->sock != NULL) {
isc_socket_detach(&query->sock);
sockcount--;
debug("sockcount=%d", sockcount);
}
free(query->recvspace);
isc_buffer_invalidate(&query->recvbuf);
isc_buffer_invalidate(&query->lengthbuf);
if (query->waiting_senddone)
query->pending_free = 1;
else
free(query);
}
/*%
* Try and clear out a lookup if we're done with it. Return 1 if
* the lookup was successfully cleared. If 1 is returned, the
* lookup pointer has been invalidated.
*/
static int
try_clear_lookup(dig_lookup_t *lookup) {
dig_query_t *q;
REQUIRE(lookup != NULL);
debug("try_clear_lookup(%p)", lookup);
if (ISC_LIST_HEAD(lookup->q) != NULL ||
ISC_LIST_HEAD(lookup->connecting) != NULL)
{
if (debugging) {
q = ISC_LIST_HEAD(lookup->q);
while (q != NULL) {
debug("query to %s still pending", q->servname);
q = ISC_LIST_NEXT(q, link);
}
q = ISC_LIST_HEAD(lookup->connecting);
while (q != NULL) {
debug("query to %s still connecting",
q->servname);
q = ISC_LIST_NEXT(q, clink);
}
}
return (0);
}
/*
* At this point, we know there are no queries on the lookup,
* so can make it go away also.
*/
destroy_lookup(lookup);
return (1);
}
void
destroy_lookup(dig_lookup_t *lookup) {
dig_server_t *s;
void *ptr;
debug("destroy");
s = ISC_LIST_HEAD(lookup->my_server_list);
while (s != NULL) {
debug("freeing server %p belonging to %p", s, lookup);
ptr = s;
s = ISC_LIST_NEXT(s, link);
ISC_LIST_DEQUEUE(lookup->my_server_list,
(dig_server_t *)ptr, link);
free(ptr);
}
if (lookup->sendmsg != NULL)
dns_message_destroy(&lookup->sendmsg);
if (lookup->querysig != NULL) {
debug("freeing buffer %p", lookup->querysig);
isc_buffer_free(&lookup->querysig);
}
if (lookup->sendspace != NULL)
free(lookup->sendspace);
if (lookup->tsigctx != NULL)
dst_context_destroy(&lookup->tsigctx);
if (lookup->ecs_addr != NULL)
free(lookup->ecs_addr);
if (lookup->ednsopts != NULL) {
size_t i;
for (i = 0; i < EDNSOPT_OPTIONS; i++) {
if (lookup->ednsopts[i].value != NULL)
free(lookup->ednsopts[i].value);
}
free(lookup->ednsopts);
}
free(lookup);
}
/*%
* If we can, start the next lookup in the queue running.
* This assumes that the lookup on the head of the queue hasn't been
* started yet. It also removes the lookup from the head of the queue,
* setting the current_lookup pointer pointing to it.
*/
void
start_lookup(void) {
debug("start_lookup()");
if (cancel_now)
return;
/*
* If there's a current lookup running, we really shouldn't get
* here.
*/
INSIST(current_lookup == NULL);
current_lookup = ISC_LIST_HEAD(lookup_list);
/*
* Put the current lookup somewhere so cancel_all can find it
*/
if (current_lookup != NULL) {
ISC_LIST_DEQUEUE(lookup_list, current_lookup, link);
if (setup_lookup(current_lookup))
do_lookup(current_lookup);
else if (next_origin(current_lookup))
check_next_lookup(current_lookup);
} else {
check_if_done();
}
}
/*%
* If we can, clear the current lookup and start the next one running.
* This calls try_clear_lookup, so may invalidate the lookup pointer.
*/
static void
check_next_lookup(dig_lookup_t *lookup) {
INSIST(!free_now);
debug("check_next_lookup(%p)", lookup);
if (ISC_LIST_HEAD(lookup->q) != NULL) {
debug("still have a worker");
return;
}
if (try_clear_lookup(lookup)) {
current_lookup = NULL;
start_lookup();
}
}
/*%
* Create and queue a new lookup as a followup to the current lookup,
* based on the supplied message and section. This is used in trace and
* name server search modes to start a new lookup using servers from
* NS records in a reply. Returns the number of followup lookups made.
*/
static int
followup_lookup(dns_message_t *msg, dig_query_t *query, dns_section_t section)
{
dig_lookup_t *lookup = NULL;
dig_server_t *srv = NULL;
dns_rdataset_t *rdataset = NULL;
dns_rdata_t rdata = DNS_RDATA_INIT;
dns_name_t *name = NULL;
isc_result_t result;
int success = 0;
int numLookups = 0;
int num;
isc_result_t lresult, addresses_result;
char bad_namestr[DNS_NAME_FORMATSIZE];
dns_name_t *domain;
int horizontal = 0, bad = 0;
INSIST(!free_now);
debug("following up %s", query->lookup->textname);
addresses_result = ISC_R_SUCCESS;
bad_namestr[0] = '\0';
for (result = dns_message_firstname(msg, section);
result == ISC_R_SUCCESS;
result = dns_message_nextname(msg, section)) {
name = NULL;
dns_message_currentname(msg, section, &name);
if (section == DNS_SECTION_AUTHORITY) {
rdataset = NULL;
result = dns_message_findtype(name, dns_rdatatype_soa,
0, &rdataset);
if (result == ISC_R_SUCCESS)
return (0);
}
rdataset = NULL;
result = dns_message_findtype(name, dns_rdatatype_ns, 0,
&rdataset);
if (result != ISC_R_SUCCESS)
continue;
debug("found NS set");
if (query->lookup->trace && !query->lookup->trace_root) {
dns_namereln_t namereln;
unsigned int nlabels;
int order;
domain = dns_fixedname_name(&query->lookup->fdomain);
namereln = dns_name_fullcompare(name, domain,
&order, &nlabels);
if (namereln == dns_namereln_equal) {
if (!horizontal)
printf(";; BAD (HORIZONTAL) REFERRAL\n");
horizontal = 1;
} else if (namereln != dns_namereln_subdomain) {
if (!bad)
printf(";; BAD REFERRAL\n");
bad = 1;
continue;
}
}
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset)) {
char namestr[DNS_NAME_FORMATSIZE];
dns_rdata_ns_t ns;
if (query->lookup->trace_root &&
query->lookup->nsfound >= MXSERV)
break;
dns_rdataset_current(rdataset, &rdata);
query->lookup->nsfound++;
result = dns_rdata_tostruct_ns(&rdata, &ns);
check_result(result, "dns_rdata_tostruct_ns");
dns_name_format(&ns.name, namestr, sizeof(namestr));
dns_rdata_freestruct_ns(&ns);
/* Initialize lookup if we've not yet */
debug("found NS %s", namestr);
if (!success) {
success = 1;
lookup_counter++;
lookup = requeue_lookup(query->lookup,
0);
cancel_lookup(query->lookup);
lookup->doing_xfr = 0;
if (!lookup->trace_root &&
section == DNS_SECTION_ANSWER)
lookup->trace = 0;
else
lookup->trace = query->lookup->trace;
lookup->ns_search_only =
query->lookup->ns_search_only;
lookup->trace_root = 0;
if (lookup->ns_search_only)
lookup->recurse = 0;
domain = dns_fixedname_name(&lookup->fdomain);
dns_name_copy(name, domain, NULL);
}
debug("adding server %s", namestr);
num = getaddresses(lookup, namestr, &lresult);
if (lresult != ISC_R_SUCCESS) {
printf("couldn't get address for '%s': %s\n",
namestr, isc_result_totext(lresult));
if (addresses_result == ISC_R_SUCCESS) {
addresses_result = lresult;
strlcpy(bad_namestr, namestr,
sizeof(bad_namestr));
}
}
numLookups += num;
dns_rdata_reset(&rdata);
}
}
if (numLookups == 0 && addresses_result != ISC_R_SUCCESS) {
fatal("couldn't get address for '%s': %s",
bad_namestr, isc_result_totext(result));
}
if (lookup == NULL &&
section == DNS_SECTION_ANSWER &&
(query->lookup->trace || query->lookup->ns_search_only))
return (followup_lookup(msg, query, DNS_SECTION_AUTHORITY));
/*
* Randomize the order the nameserver will be tried.
*/
if (numLookups > 1) {
uint32_t i, j;
dig_serverlist_t my_server_list;
dig_server_t *next;
ISC_LIST_INIT(my_server_list);
i = numLookups;
for (srv = ISC_LIST_HEAD(lookup->my_server_list);
srv != NULL;
srv = ISC_LIST_HEAD(lookup->my_server_list)) {
INSIST(i > 0);
j = arc4random_uniform(i);
next = ISC_LIST_NEXT(srv, link);
while (j-- > 0 && next != NULL) {
srv = next;
next = ISC_LIST_NEXT(srv, link);
}
ISC_LIST_DEQUEUE(lookup->my_server_list, srv, link);
ISC_LIST_APPEND(my_server_list, srv, link);
i--;
}
ISC_LIST_APPENDLIST(lookup->my_server_list,
my_server_list, link);
}
return (numLookups);
}
/*%
* Create and queue a new lookup using the next origin from the search
* list, read in setup_system().
*
* Return 1 iff there was another searchlist entry.
*/
static int
next_origin(dig_lookup_t *oldlookup) {
dig_lookup_t *newlookup;
dig_searchlist_t *search;
dns_fixedname_t fixed;
dns_name_t *name;
isc_result_t result;
INSIST(!free_now);
debug("next_origin()");
debug("following up %s", oldlookup->textname);
if (!usesearch)
/*
* We're not using a search list, so don't even think
* about finding the next entry.
*/
return (0);
/*
* Check for a absolute name or ndots being met.
*/
dns_fixedname_init(&fixed);
name = dns_fixedname_name(&fixed);
result = dns_name_fromstring2(name, oldlookup->textname, NULL, 0);
if (result == ISC_R_SUCCESS &&
(dns_name_isabsolute(name) ||
(int)dns_name_countlabels(name) > ndots))
return (0);
if (oldlookup->origin == NULL && !oldlookup->need_search)
/*
* Then we just did rootorg; there's nothing left.
*/
return (0);
if (oldlookup->origin == NULL && oldlookup->need_search) {
newlookup = requeue_lookup(oldlookup, 1);
newlookup->origin = ISC_LIST_HEAD(search_list);
newlookup->need_search = 0;
} else {
search = ISC_LIST_NEXT(oldlookup->origin, link);
if (search == NULL && oldlookup->done_as_is)
return (0);
newlookup = requeue_lookup(oldlookup, 1);
newlookup->origin = search;
}
cancel_lookup(oldlookup);
return (1);
}
/*%
* Insert an SOA record into the sendmessage in a lookup. Used for
* creating IXFR queries.
*/
static void
insert_soa(dig_lookup_t *lookup) {
isc_result_t result;
dns_rdata_soa_t soa;
dns_rdata_t *rdata = NULL;
dns_rdatalist_t *rdatalist = NULL;
dns_rdataset_t *rdataset = NULL;
dns_name_t *soaname = NULL;
debug("insert_soa()");
soa.serial = lookup->ixfr_serial;
soa.refresh = 0;
soa.retry = 0;
soa.expire = 0;
soa.minimum = 0;
soa.common.rdclass = lookup->rdclass;
soa.common.rdtype = dns_rdatatype_soa;
dns_name_init(&soa.origin, NULL);
dns_name_init(&soa.contact, NULL);
dns_name_clone(dns_rootname, &soa.origin);
dns_name_clone(dns_rootname, &soa.contact);
isc_buffer_init(&lookup->rdatabuf, lookup->rdatastore,
sizeof(lookup->rdatastore));
result = dns_message_gettemprdata(lookup->sendmsg, &rdata);
check_result(result, "dns_message_gettemprdata");
result = dns_rdata_fromstruct_soa(rdata, lookup->rdclass,
dns_rdatatype_soa, &soa,
&lookup->rdatabuf);
check_result(result, "isc_rdata_fromstruct_soa");
result = dns_message_gettemprdatalist(lookup->sendmsg, &rdatalist);
check_result(result, "dns_message_gettemprdatalist");
result = dns_message_gettemprdataset(lookup->sendmsg, &rdataset);
check_result(result, "dns_message_gettemprdataset");
dns_rdatalist_init(rdatalist);
rdatalist->type = dns_rdatatype_soa;
rdatalist->rdclass = lookup->rdclass;
ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
dns_rdatalist_tordataset(rdatalist, rdataset);
result = dns_message_gettempname(lookup->sendmsg, &soaname);
check_result(result, "dns_message_gettempname");
dns_name_init(soaname, NULL);
dns_name_clone(lookup->name, soaname);
ISC_LIST_INIT(soaname->list);
ISC_LIST_APPEND(soaname->list, rdataset, link);
dns_message_addname(lookup->sendmsg, soaname, DNS_SECTION_AUTHORITY);
}
static void
compute_cookie(unsigned char *clientcookie, size_t len) {
/* XXXMPA need to fix, should be per server. */
INSIST(len >= 8U);
memmove(clientcookie, cookie_secret, 8);
}
#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
static void
populate_root_hints(void)
{
dig_server_t *newsrv;
size_t i;
if (!ISC_LIST_EMPTY(root_hints_server_list))
return;
for (i = 0; i < nitems(root_hints); i++) {
if (!have_ipv4 && root_hints[i].af == AF_INET)
continue;
if (!have_ipv6 && root_hints[i].af == AF_INET6)
continue;
newsrv = make_server(root_hints[i].ns, root_hints[i].ns);
ISC_LINK_INIT(newsrv, link);
ISC_LIST_ENQUEUE(root_hints_server_list, newsrv, link);
}
}
#undef nitems
/*%
* Setup the supplied lookup structure, making it ready to start sending
* queries to servers. Create and initialize the message to be sent as
* well as the query structures and buffer space for the replies. If the
* server list is empty, clone it from the system default list.
*/
int
setup_lookup(dig_lookup_t *lookup) {
isc_result_t result;
uint32_t id;
unsigned int len;
dig_server_t *serv;
dig_query_t *query;
isc_buffer_t b;
dns_compress_t cctx;
char store[MXNAME];
char ecsbuf[20];
char sitbuf[256];
REQUIRE(lookup != NULL);
INSIST(!free_now);
debug("setup_lookup(%p)", lookup);
result = dns_message_create(DNS_MESSAGE_INTENTRENDER,
&lookup->sendmsg);
check_result(result, "dns_message_create");
if (lookup->new_search) {
debug("resetting lookup counter.");
lookup_counter = 0;
}
if (ISC_LIST_EMPTY(lookup->my_server_list)) {
if (lookup->trace && lookup->trace_root) {
populate_root_hints();
clone_server_list(root_hints_server_list,
&lookup->my_server_list);
} else {
debug("cloning server list");
clone_server_list(server_list,
&lookup->my_server_list);
}
}
result = dns_message_gettempname(lookup->sendmsg, &lookup->name);
check_result(result, "dns_message_gettempname");
dns_name_init(lookup->name, NULL);
isc_buffer_init(&lookup->namebuf, lookup->name_space,
sizeof(lookup->name_space));
isc_buffer_init(&lookup->onamebuf, lookup->oname_space,
sizeof(lookup->oname_space));
/*
* If the name has too many dots, force the origin to be NULL
* (which produces an absolute lookup). Otherwise, take the origin
* we have if there's one in the struct already. If it's NULL,
* take the first entry in the searchlist iff either usesearch
* is TRUE or we got a domain line in the resolv.conf file.
*/
if (lookup->new_search) {
if ((count_dots(lookup->textname) >= ndots) || !usesearch) {
lookup->origin = NULL; /* Force abs lookup */
lookup->done_as_is = 1;
lookup->need_search = usesearch;
} else if (lookup->origin == NULL && usesearch) {
lookup->origin = ISC_LIST_HEAD(search_list);
lookup->need_search = 0;
}
}
if (lookup->origin != NULL) {
debug("trying origin %s", lookup->origin->origin);
result = dns_message_gettempname(lookup->sendmsg,
&lookup->oname);
check_result(result, "dns_message_gettempname");
dns_name_init(lookup->oname, NULL);
/* XXX Helper funct to conv char* to name? */
len = (unsigned int) strlen(lookup->origin->origin);
isc_buffer_init(&b, lookup->origin->origin, len);
isc_buffer_add(&b, len);
result = dns_name_fromtext(lookup->oname, &b, dns_rootname,
0, &lookup->onamebuf);
if (result != ISC_R_SUCCESS) {
dns_message_puttempname(lookup->sendmsg,
&lookup->name);
dns_message_puttempname(lookup->sendmsg,
&lookup->oname);
fatal("'%s' is not in legal name syntax (%s)",
lookup->origin->origin,
isc_result_totext(result));
}
if (lookup->trace && lookup->trace_root) {
dns_name_clone(dns_rootname, lookup->name);
} else {
dns_fixedname_t fixed;
dns_name_t *name;
dns_fixedname_init(&fixed);
name = dns_fixedname_name(&fixed);
len = (unsigned int) strlen(lookup->textname);
isc_buffer_init(&b, lookup->textname, len);
isc_buffer_add(&b, len);
result = dns_name_fromtext(name, &b, NULL, 0, NULL);
if (result == ISC_R_SUCCESS &&
!dns_name_isabsolute(name))
result = dns_name_concatenate(name,
lookup->oname,
lookup->name,
&lookup->namebuf);
else if (result == ISC_R_SUCCESS)
result = dns_name_copy(name, lookup->name,
&lookup->namebuf);
if (result != ISC_R_SUCCESS) {
dns_message_puttempname(lookup->sendmsg,
&lookup->name);
dns_message_puttempname(lookup->sendmsg,
&lookup->oname);
if (result == DNS_R_NAMETOOLONG)
return (0);
fatal("'%s' is not in legal name syntax (%s)",
lookup->textname,
isc_result_totext(result));
}
}
dns_message_puttempname(lookup->sendmsg, &lookup->oname);
} else
{
debug("using root origin");
if (lookup->trace && lookup->trace_root)
dns_name_clone(dns_rootname, lookup->name);
else {
len = (unsigned int) strlen(lookup->textname);
isc_buffer_init(&b, lookup->textname, len);
isc_buffer_add(&b, len);
result = dns_name_fromtext(lookup->name, &b,
dns_rootname, 0,
&lookup->namebuf);
}
if (result != ISC_R_SUCCESS) {
dns_message_puttempname(lookup->sendmsg,
&lookup->name);
fatal("'%s' is not a legal name "
"(%s)", lookup->textname,
isc_result_totext(result));
}
}
dns_name_format(lookup->name, store, sizeof(store));
dighost_trying(store, lookup);
INSIST(dns_name_isabsolute(lookup->name));
id = arc4random();
lookup->sendmsg->id = (unsigned short)id & 0xFFFF;
lookup->sendmsg->opcode = lookup->opcode;
lookup->msgcounter = 0;
/*
* If this is a trace request, completely disallow recursion, since
* it's meaningless for traces.
*/
if (lookup->trace || (lookup->ns_search_only && !lookup->trace_root))
lookup->recurse = 0;
if (lookup->recurse &&
lookup->rdtype != dns_rdatatype_axfr &&
lookup->rdtype != dns_rdatatype_ixfr) {
debug("recursive query");
lookup->sendmsg->flags |= DNS_MESSAGEFLAG_RD;
}
/* XXX aaflag */
if (lookup->aaonly) {
debug("AA query");
lookup->sendmsg->flags |= DNS_MESSAGEFLAG_AA;
}
if (lookup->adflag) {
debug("AD query");
lookup->sendmsg->flags |= DNS_MESSAGEFLAG_AD;
}
if (lookup->cdflag) {
debug("CD query");
lookup->sendmsg->flags |= DNS_MESSAGEFLAG_CD;
}
dns_message_addname(lookup->sendmsg, lookup->name,
DNS_SECTION_QUESTION);
if (lookup->trace && lookup->trace_root) {
lookup->qrdtype = lookup->rdtype;
lookup->rdtype = dns_rdatatype_ns;
}
if ((lookup->rdtype == dns_rdatatype_axfr) ||
(lookup->rdtype == dns_rdatatype_ixfr)) {
/*
* Force TCP mode if we're doing an axfr.
*/
if (lookup->rdtype == dns_rdatatype_axfr) {
lookup->doing_xfr = 1;
lookup->tcp_mode = 1;
} else if (lookup->tcp_mode) {
lookup->doing_xfr = 1;
}
}
add_question(lookup->sendmsg, lookup->name, lookup->rdclass,
lookup->rdtype);
/* add_soa */
if (lookup->rdtype == dns_rdatatype_ixfr)
insert_soa(lookup);
/* XXX Insist this? */
lookup->tsigctx = NULL;
lookup->querysig = NULL;
if (tsigkey != NULL) {
debug("initializing keys");
result = dns_message_settsigkey(lookup->sendmsg, tsigkey);
check_result(result, "dns_message_settsigkey");
}
lookup->sendspace = malloc(COMMSIZE);
if (lookup->sendspace == NULL)
fatal("memory allocation failure");
result = dns_compress_init(&cctx, -1);
check_result(result, "dns_compress_init");
debug("starting to render the message");
isc_buffer_init(&lookup->renderbuf, lookup->sendspace, COMMSIZE);
result = dns_message_renderbegin(lookup->sendmsg, &cctx,
&lookup->renderbuf);
check_result(result, "dns_message_renderbegin");
if (lookup->udpsize > 0 || lookup->dnssec ||
lookup->edns > -1 || lookup->ecs_addr != NULL)
{
#define MAXOPTS (EDNSOPT_OPTIONS + DNS_EDNSOPTIONS)
dns_ednsopt_t opts[MAXOPTS];
unsigned int flags;
unsigned int i = 0;
if (lookup->udpsize == 0)
lookup->udpsize = 4096;
if (lookup->edns < 0)
lookup->edns = 0;
if (lookup->nsid) {
INSIST(i < MAXOPTS);
opts[i].code = DNS_OPT_NSID;
opts[i].length = 0;
opts[i].value = NULL;
i++;
}
if (lookup->ecs_addr != NULL) {
uint8_t addr[16];
uint16_t family;
uint32_t plen;
struct sockaddr *sa;
struct sockaddr_in *sin;
struct sockaddr_in6 *sin6;
size_t addrl;
sa = (struct sockaddr *)lookup->ecs_addr;
plen = lookup->ecs_plen;
/* Round up prefix len to a multiple of 8 */
addrl = (plen + 7) / 8;
INSIST(i < MAXOPTS);
opts[i].code = DNS_OPT_CLIENT_SUBNET;
opts[i].length = (uint16_t) addrl + 4;
check_result(result, "isc_buffer_allocate");
/*
* XXXMUKS: According to RFC7871, "If there is
* no ADDRESS set, i.e., SOURCE PREFIX-LENGTH is
* set to 0, then FAMILY SHOULD be set to the
* transport over which the query is sent."
*
* However, at this point we don't know what
* transport(s) we'll be using, so we can't
* set the value now. For now, we're using
* IPv4 as the default the +subnet option
* used an IPv4 prefix, or for +subnet=0,
* and IPv6 if the +subnet option used an
* IPv6 prefix.
*
* (For future work: preserve the offset into
* the buffer where the family field is;
* that way we can update it in send_udp()
* or send_tcp_connect() once we know
* what it outght to be.)
*/
switch (sa->sa_family) {
case AF_UNSPEC:
INSIST(plen == 0);
family = 1;
break;
case AF_INET:
INSIST(plen <= 32);
family = 1;
sin = (struct sockaddr_in *) sa;
memmove(addr, &sin->sin_addr, addrl);
break;
case AF_INET6:
INSIST(plen <= 128);
family = 2;
sin6 = (struct sockaddr_in6 *) sa;
memmove(addr, &sin6->sin6_addr, addrl);
break;
default:
INSIST(0);
}
isc_buffer_init(&b, ecsbuf, sizeof(ecsbuf));
/* family */
isc_buffer_putuint16(&b, family);
/* source prefix-length */
isc_buffer_putuint8(&b, plen);
/* scope prefix-length */
isc_buffer_putuint8(&b, 0);
/* address */
if (addrl > 0) {
/* Mask off last address byte */
if ((plen % 8) != 0)
addr[addrl - 1] &=
~0U << (8 - (plen % 8));
isc_buffer_putmem(&b, addr,
(unsigned)addrl);
}
opts[i].value = (uint8_t *) ecsbuf;
i++;
}
if (lookup->sit) {
INSIST(i < MAXOPTS);
opts[i].code = DNS_OPT_COOKIE;
if (lookup->sitvalue != NULL) {
isc_buffer_init(&b, sitbuf, sizeof(sitbuf));
result = isc_hex_decodestring(lookup->sitvalue,
&b);
check_result(result, "isc_hex_decodestring");
opts[i].value = isc_buffer_base(&b);
opts[i].length = isc_buffer_usedlength(&b);
} else {
compute_cookie(cookie, sizeof(cookie));
opts[i].length = 8;
opts[i].value = cookie;
}
i++;
}
if (lookup->expire) {
INSIST(i < MAXOPTS);
opts[i].code = DNS_OPT_EXPIRE;
opts[i].length = 0;
opts[i].value = NULL;
i++;
}
if (lookup->ednsoptscnt != 0) {
INSIST(i + lookup->ednsoptscnt <= MAXOPTS);
memmove(&opts[i], lookup->ednsopts,
sizeof(dns_ednsopt_t) * lookup->ednsoptscnt);
i += lookup->ednsoptscnt;
}
flags = lookup->ednsflags;
flags &= ~DNS_MESSAGEEXTFLAG_DO;
if (lookup->dnssec)
flags |= DNS_MESSAGEEXTFLAG_DO;
add_opt(lookup->sendmsg, lookup->udpsize,
lookup->edns, flags, opts, i);
}
result = dns_message_rendersection(lookup->sendmsg,
DNS_SECTION_QUESTION);
check_result(result, "dns_message_rendersection");
result = dns_message_rendersection(lookup->sendmsg,
DNS_SECTION_AUTHORITY);
check_result(result, "dns_message_rendersection");
result = dns_message_renderend(lookup->sendmsg);
check_result(result, "dns_message_renderend");
debug("done rendering");
dns_compress_invalidate(&cctx);
/*
* Force TCP mode if the request is larger than 512 bytes.
*/
if (isc_buffer_usedlength(&lookup->renderbuf) > 512)
lookup->tcp_mode = 1;
lookup->pending = 0;
for (serv = ISC_LIST_HEAD(lookup->my_server_list);
serv != NULL;
serv = ISC_LIST_NEXT(serv, link)) {
query = malloc(sizeof(dig_query_t));
if (query == NULL)
fatal("memory allocation failure in %s:%d",
__FILE__, __LINE__);
debug("create query %p linked to lookup %p",
query, lookup);
query->lookup = lookup;
query->timer = NULL;
query->waiting_connect = 0;
query->waiting_senddone = 0;
query->pending_free = 0;
query->recv_made = 0;
query->first_pass = 1;
query->first_soa_rcvd = 0;
query->second_rr_rcvd = 0;
query->first_repeat_rcvd = 0;
query->warn_id = 1;
query->timedout = 0;
query->first_rr_serial = 0;
query->second_rr_serial = 0;
query->servname = serv->servername;
query->userarg = serv->userarg;
query->rr_count = 0;
query->msg_count = 0;
query->byte_count = 0;
query->ixfr_axfr = 0;
ISC_LIST_INIT(query->recvlist);
ISC_LIST_INIT(query->lengthlist);
query->sock = NULL;
query->recvspace = malloc(COMMSIZE);
if (query->recvspace == NULL)
fatal("memory allocation failure");
isc_buffer_init(&query->recvbuf, query->recvspace, COMMSIZE);
isc_buffer_init(&query->lengthbuf, query->lengthspace, 2);
isc_buffer_init(&query->slbuf, query->slspace, 2);
query->sendbuf = lookup->renderbuf;
ISC_LINK_INIT(query, clink);
ISC_LINK_INIT(query, link);
ISC_LIST_ENQUEUE(lookup->q, query, link);
}
/* XXX qrflag, print_query, etc... */
if (!ISC_LIST_EMPTY(lookup->q) && qr) {
extrabytes = 0;
dighost_printmessage(ISC_LIST_HEAD(lookup->q), lookup->sendmsg,
1);
}
return (1);
}
/*%
* Event handler for send completion. Track send counter, and clear out
* the query if the send was canceled.
*/
static void
send_done(isc_task_t *_task, isc_event_t *event) {
isc_socketevent_t *sevent = (isc_socketevent_t *)event;
isc_buffer_t *b = NULL;
dig_query_t *query, *next;
dig_lookup_t *l;
REQUIRE(event->ev_type == ISC_SOCKEVENT_SENDDONE);
UNUSED(_task);
debug("send_done()");
sendcount--;
debug("sendcount=%d", sendcount);
INSIST(sendcount >= 0);
for (b = ISC_LIST_HEAD(sevent->bufferlist);
b != NULL;
b = ISC_LIST_HEAD(sevent->bufferlist)) {
ISC_LIST_DEQUEUE(sevent->bufferlist, b, link);
free(b);
}
query = event->ev_arg;
query->waiting_senddone = 0;
l = query->lookup;
if (l->ns_search_only && !l->trace_root && !l->tcp_mode) {
debug("sending next, since searching");
next = ISC_LIST_NEXT(query, link);
if (next != NULL)
send_udp(next);
}
isc_event_free(&event);
if (query->pending_free)
free(query);
check_if_done();
}
/*%
* Cancel a lookup, sending isc_socket_cancel() requests to all outstanding
* IO sockets. The cancel handlers should take care of cleaning up the
* query and lookup structures
*/
static void
cancel_lookup(dig_lookup_t *lookup) {
dig_query_t *query, *next;
debug("cancel_lookup()");
query = ISC_LIST_HEAD(lookup->q);
while (query != NULL) {
next = ISC_LIST_NEXT(query, link);
if (query->sock != NULL) {
isc_socket_cancel(query->sock, global_task,
ISC_SOCKCANCEL_ALL);
check_if_done();
} else {
clear_query(query);
}
query = next;
}
lookup->pending = 0;
lookup->retries = 0;
}
static void
bringup_timer(dig_query_t *query, unsigned int default_timeout) {
dig_lookup_t *l;
unsigned int local_timeout;
isc_result_t result;
debug("bringup_timer()");
/*
* If the timer already exists, that means we're calling this
* a second time (for a retry). Don't need to recreate it,
* just reset it.
*/
l = query->lookup;
if (ISC_LINK_LINKED(query, link) && ISC_LIST_NEXT(query, link) != NULL)
local_timeout = SERVER_TIMEOUT;
else {
if (timeout == 0)
local_timeout = default_timeout;
else
local_timeout = timeout;
}
debug("have local timeout of %d", local_timeout);
l->interval.tv_sec = local_timeout;
l->interval.tv_nsec = 0;
if (query->timer != NULL)
isc_timer_detach(&query->timer);
result = isc_timer_create(timermgr,
&l->interval, global_task, connect_timeout,
query, &query->timer);
check_result(result, "isc_timer_create");
}
static void
force_timeout(dig_query_t *query) {
isc_event_t *event;
debug("force_timeout ()");
event = isc_event_allocate(query, ISC_TIMEREVENT_IDLE,
connect_timeout, query,
sizeof(isc_event_t));
if (event == NULL) {
fatal("isc_event_allocate: %s",
isc_result_totext(ISC_R_NOMEMORY));
}
isc_task_send(global_task, &event);
/*
* The timer may have expired if, for example, get_address() takes
* long time and the timer was running on a different thread.
* We need to cancel the possible timeout event not to confuse
* ourselves due to the duplicate events.
*/
if (query->timer != NULL)
isc_timer_detach(&query->timer);
}
static void
connect_done(isc_task_t *task, isc_event_t *event);
/*%
* Unlike send_udp, this can't be called multiple times with the same
* query. When we retry TCP, we requeue the whole lookup, which should
* start anew.
*/
static void
send_tcp_connect(dig_query_t *query) {
isc_result_t result;
dig_query_t *next;
dig_lookup_t *l;
debug("send_tcp_connect(%p)", query);
l = query->lookup;
query->waiting_connect = 1;
query->lookup->current_query = query;
result = get_address(query->servname, port, &query->sockaddr);
if (result != ISC_R_SUCCESS) {
/*
* This servname doesn't have an address. Try the next server
* by triggering an immediate 'timeout' (we lie, but the effect
* is the same).
*/
force_timeout(query);
return;
}
if (specified_source &&
(isc_sockaddr_pf(&query->sockaddr) !=
isc_sockaddr_pf(&bind_address))) {
printf(";; Skipping server %s, incompatible "
"address family\n", query->servname);
query->waiting_connect = 0;
if (ISC_LINK_LINKED(query, link))
next = ISC_LIST_NEXT(query, link);
else
next = NULL;
l = query->lookup;
clear_query(query);
if (next == NULL) {
printf(";; No acceptable nameservers\n");
check_next_lookup(l);
return;
}
send_tcp_connect(next);
return;
}
INSIST(query->sock == NULL);
if (keep != NULL && isc_sockaddr_equal(&keepaddr, &query->sockaddr)) {
sockcount++;
isc_socket_attach(keep, &query->sock);
query->waiting_connect = 0;
launch_next_query(query, 1);
goto search;
}
result = isc_socket_create(socketmgr,
isc_sockaddr_pf(&query->sockaddr),
isc_sockettype_tcp, &query->sock);
check_result(result, "isc_socket_create");
sockcount++;
debug("sockcount=%d", sockcount);
if (specified_source)
result = isc_socket_bind(query->sock, &bind_address,
ISC_SOCKET_REUSEADDRESS);
else {
if ((isc_sockaddr_pf(&query->sockaddr) == AF_INET) &&
have_ipv4)
isc_sockaddr_any(&bind_any);
else
isc_sockaddr_any6(&bind_any);
result = isc_socket_bind(query->sock, &bind_any, 0);
}
check_result(result, "isc_socket_bind");
bringup_timer(query, TCP_TIMEOUT);
result = isc_socket_connect(query->sock, &query->sockaddr,
global_task, connect_done, query);
check_result(result, "isc_socket_connect");
search:
/*
* If we're at the endgame of a nameserver search, we need to
* immediately bring up all the queries. Do it here.
*/
if (l->ns_search_only && !l->trace_root) {
debug("sending next, since searching");
if (ISC_LINK_LINKED(query, link)) {
next = ISC_LIST_NEXT(query, link);
ISC_LIST_DEQUEUE(l->q, query, link);
} else
next = NULL;
ISC_LIST_ENQUEUE(l->connecting, query, clink);
if (next != NULL)
send_tcp_connect(next);
}
}
static isc_buffer_t *
clone_buffer(isc_buffer_t *source) {
isc_buffer_t *buffer;
buffer = malloc(sizeof(*buffer));
if (buffer == NULL)
fatal("memory allocation failure in %s:%d",
__FILE__, __LINE__);
*buffer = *source;
return (buffer);
}
/*%
* Send a UDP packet to the remote nameserver, possible starting the
* recv action as well. Also make sure that the timer is running and
* is properly reset.
*/
static void
send_udp(dig_query_t *query) {
dig_lookup_t *l = NULL;
isc_result_t result;
isc_buffer_t *sendbuf;
debug("send_udp(%p)", query);
l = query->lookup;
bringup_timer(query, UDP_TIMEOUT);
l->current_query = query;
debug("working on lookup %p, query %p", query->lookup, query);
if (!query->recv_made) {
/* XXX Check the sense of this, need assertion? */
query->waiting_connect = 0;
result = get_address(query->servname, port, &query->sockaddr);
if (result != ISC_R_SUCCESS) {
/* This servname doesn't have an address. */
force_timeout(query);
return;
}
result = isc_socket_create(socketmgr,
isc_sockaddr_pf(&query->sockaddr),
isc_sockettype_udp, &query->sock);
check_result(result, "isc_socket_create");
sockcount++;
debug("sockcount=%d", sockcount);
if (specified_source) {
result = isc_socket_bind(query->sock, &bind_address,
ISC_SOCKET_REUSEADDRESS);
} else {
isc_sockaddr_anyofpf(&bind_any,
isc_sockaddr_pf(&query->sockaddr));
result = isc_socket_bind(query->sock, &bind_any, 0);
}
check_result(result, "isc_socket_bind");
query->recv_made = 1;
ISC_LINK_INIT(&query->recvbuf, link);
ISC_LIST_ENQUEUE(query->recvlist, &query->recvbuf,
link);
debug("recving with lookup=%p, query=%p, sock=%p",
query->lookup, query, query->sock);
result = isc_socket_recvv(query->sock, &query->recvlist, 1,
global_task, recv_done, query);
check_result(result, "isc_socket_recvv");
recvcount++;
debug("recvcount=%d", recvcount);
}
ISC_LIST_INIT(query->sendlist);
sendbuf = clone_buffer(&query->sendbuf);
ISC_LIST_ENQUEUE(query->sendlist, sendbuf, link);
debug("sending a request");
clock_gettime(CLOCK_MONOTONIC, &query->time_sent);
INSIST(query->sock != NULL);
query->waiting_senddone = 1;
result = isc_socket_sendtov2(query->sock, &query->sendlist,
global_task, send_done, query,
&query->sockaddr, NULL,
ISC_SOCKFLAG_NORETRY);
check_result(result, "isc_socket_sendtov");
sendcount++;
}
/*%
* IO timeout handler, used for both connect and recv timeouts. If
* retries are still allowed, either resend the UDP packet or queue a
* new TCP lookup. Otherwise, cancel the lookup.
*/
static void
connect_timeout(isc_task_t *task, isc_event_t *event) {
dig_lookup_t *l = NULL;
dig_query_t *query = NULL, *cq;
UNUSED(task);
REQUIRE(event->ev_type == ISC_TIMEREVENT_IDLE);
debug("connect_timeout()");
query = event->ev_arg;
l = query->lookup;
isc_event_free(&event);
INSIST(!free_now);
if ((query != NULL) && (query->lookup->current_query != NULL) &&
ISC_LINK_LINKED(query->lookup->current_query, link) &&
(ISC_LIST_NEXT(query->lookup->current_query, link) != NULL)) {
debug("trying next server...");
cq = query->lookup->current_query;
if (!l->tcp_mode)
send_udp(ISC_LIST_NEXT(cq, link));
else {
if (query->sock != NULL)
isc_socket_cancel(query->sock, NULL,
ISC_SOCKCANCEL_ALL);
send_tcp_connect(ISC_LIST_NEXT(cq, link));
}
return;
}
if (l->tcp_mode && query->sock != NULL) {
query->timedout = 1;
isc_socket_cancel(query->sock, NULL, ISC_SOCKCANCEL_ALL);
}
if (l->retries > 1) {
if (!l->tcp_mode) {
l->retries--;
debug("resending UDP request to first server");
send_udp(ISC_LIST_HEAD(l->q));
} else {
debug("making new TCP request, %d tries left",
l->retries);
l->retries--;
requeue_lookup(l, 1);
cancel_lookup(l);
check_next_lookup(l);
}
} else {
if (!l->ns_search_only) {
fputs(l->cmdline, stdout);
printf(";; connection timed out; no servers could be "
"reached\n");
}
cancel_lookup(l);
check_next_lookup(l);
if (exitcode < 9)
exitcode = 9;
}
}
/*%
* Event handler for the TCP recv which gets the length header of TCP
* packets. Start the next recv of length bytes.
*/
static void
tcp_length_done(isc_task_t *task, isc_event_t *event) {
isc_socketevent_t *sevent;
isc_buffer_t *b = NULL;
isc_result_t result;
dig_query_t *query = NULL;
dig_lookup_t *l, *n;
uint16_t length;
REQUIRE(event->ev_type == ISC_SOCKEVENT_RECVDONE);
INSIST(!free_now);
UNUSED(task);
debug("tcp_length_done()");
sevent = (isc_socketevent_t *)event;
query = event->ev_arg;
recvcount--;
INSIST(recvcount >= 0);
b = ISC_LIST_HEAD(sevent->bufferlist);
INSIST(b == &query->lengthbuf);
ISC_LIST_DEQUEUE(sevent->bufferlist, b, link);
if (sevent->result == ISC_R_CANCELED) {
isc_event_free(&event);
l = query->lookup;
clear_query(query);
check_next_lookup(l);
return;
}
if (sevent->result != ISC_R_SUCCESS) {
char sockstr[ISC_SOCKADDR_FORMATSIZE];
isc_sockaddr_format(&query->sockaddr, sockstr,
sizeof(sockstr));
printf(";; communications error to %s: %s\n",
sockstr, isc_result_totext(sevent->result));
if (keep != NULL)
isc_socket_detach(&keep);
l = query->lookup;
isc_socket_detach(&query->sock);
sockcount--;
debug("sockcount=%d", sockcount);
INSIST(sockcount >= 0);
if (sevent->result == ISC_R_EOF && l->eoferr == 0U) {
n = requeue_lookup(l, 1);
n->eoferr++;
}
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
}
length = isc_buffer_getuint16(b);
if (length == 0) {
isc_event_free(&event);
launch_next_query(query, 0);
return;
}
/*
* Even though the buffer was already init'ed, we need
* to redo it now, to force the length we want.
*/
isc_buffer_invalidate(&query->recvbuf);
isc_buffer_init(&query->recvbuf, query->recvspace, length);
ENSURE(ISC_LIST_EMPTY(query->recvlist));
ISC_LINK_INIT(&query->recvbuf, link);
ISC_LIST_ENQUEUE(query->recvlist, &query->recvbuf, link);
debug("recving with lookup=%p, query=%p", query->lookup, query);
result = isc_socket_recvv(query->sock, &query->recvlist, length, task,
recv_done, query);
check_result(result, "isc_socket_recvv");
recvcount++;
debug("resubmitted recv request with length %d, recvcount=%d",
length, recvcount);
isc_event_free(&event);
}
/*%
* For transfers that involve multiple recvs (XFR's in particular),
* launch the next recv.
*/
static void
launch_next_query(dig_query_t *query, int include_question) {
isc_result_t result;
dig_lookup_t *l;
isc_buffer_t *buffer;
INSIST(!free_now);
debug("launch_next_query()");
if (!query->lookup->pending) {
debug("ignoring launch_next_query because !pending");
isc_socket_detach(&query->sock);
sockcount--;
debug("sockcount=%d", sockcount);
INSIST(sockcount >= 0);
query->waiting_connect = 0;
l = query->lookup;
clear_query(query);
check_next_lookup(l);
return;
}
isc_buffer_clear(&query->slbuf);
isc_buffer_clear(&query->lengthbuf);
isc_buffer_putuint16(&query->slbuf, (uint16_t) query->sendbuf.used);
ISC_LIST_INIT(query->sendlist);
ISC_LINK_INIT(&query->slbuf, link);
if (!query->first_soa_rcvd) {
buffer = clone_buffer(&query->slbuf);
ISC_LIST_ENQUEUE(query->sendlist, buffer, link);
if (include_question) {
buffer = clone_buffer(&query->sendbuf);
ISC_LIST_ENQUEUE(query->sendlist, buffer, link);
}
}
ISC_LINK_INIT(&query->lengthbuf, link);
ISC_LIST_ENQUEUE(query->lengthlist, &query->lengthbuf, link);
result = isc_socket_recvv(query->sock, &query->lengthlist, 0,
global_task, tcp_length_done, query);
check_result(result, "isc_socket_recvv");
recvcount++;
debug("recvcount=%d", recvcount);
if (!query->first_soa_rcvd) {
debug("sending a request in launch_next_query");
clock_gettime(CLOCK_MONOTONIC, &query->time_sent);
query->waiting_senddone = 1;
result = isc_socket_sendv(query->sock, &query->sendlist,
global_task, send_done, query);
check_result(result, "isc_socket_sendv");
sendcount++;
debug("sendcount=%d", sendcount);
}
query->waiting_connect = 0;
return;
}
/*%
* Event handler for TCP connect complete. Make sure the connection was
* successful, then pass into launch_next_query to actually send the
* question.
*/
static void
connect_done(isc_task_t *task, isc_event_t *event) {
char sockstr[ISC_SOCKADDR_FORMATSIZE];
isc_socketevent_t *sevent = NULL;
dig_query_t *query = NULL, *next;
dig_lookup_t *l;
UNUSED(task);
REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);
INSIST(!free_now);
debug("connect_done()");
sevent = (isc_socketevent_t *)event;
query = sevent->ev_arg;
INSIST(query->waiting_connect);
query->waiting_connect = 0;
if (sevent->result == ISC_R_CANCELED) {
debug("in cancel handler");
isc_sockaddr_format(&query->sockaddr, sockstr, sizeof(sockstr));
if (query->timedout)
printf(";; Connection to %s(%s) for %s failed: %s.\n",
sockstr, query->servname,
query->lookup->textname,
isc_result_totext(ISC_R_TIMEDOUT));
isc_socket_detach(&query->sock);
INSIST(sockcount > 0);
sockcount--;
debug("sockcount=%d", sockcount);
query->waiting_connect = 0;
isc_event_free(&event);
l = query->lookup;
clear_query(query);
check_next_lookup(l);
return;
}
if (sevent->result != ISC_R_SUCCESS) {
debug("unsuccessful connection: %s",
isc_result_totext(sevent->result));
isc_sockaddr_format(&query->sockaddr, sockstr, sizeof(sockstr));
if (sevent->result != ISC_R_CANCELED)
printf(";; Connection to %s(%s) for %s failed: "
"%s.\n", sockstr,
query->servname, query->lookup->textname,
isc_result_totext(sevent->result));
isc_socket_detach(&query->sock);
INSIST(sockcount > 0);
sockcount--;
/* XXX Clean up exitcodes */
if (exitcode < 9)
exitcode = 9;
debug("sockcount=%d", sockcount);
query->waiting_connect = 0;
isc_event_free(&event);
l = query->lookup;
if ((l->current_query != NULL) &&
(ISC_LINK_LINKED(l->current_query, link)))
next = ISC_LIST_NEXT(l->current_query, link);
else
next = NULL;
clear_query(query);
if (next != NULL) {
bringup_timer(next, TCP_TIMEOUT);
send_tcp_connect(next);
} else
check_next_lookup(l);
return;
}
if (keep_open) {
if (keep != NULL)
isc_socket_detach(&keep);
isc_socket_attach(query->sock, &keep);
keepaddr = query->sockaddr;
}
launch_next_query(query, 1);
isc_event_free(&event);
}
/*%
* Check if the ongoing XFR needs more data before it's complete, using
* the semantics of IXFR and AXFR protocols. Much of the complexity of
* this routine comes from determining when an IXFR is complete.
* 0 means more data is on the way, and the recv has been issued.
*/
static int
check_for_more_data(dig_query_t *query, dns_message_t *msg,
isc_socketevent_t *sevent)
{
dns_rdataset_t *rdataset = NULL;
dns_rdata_t rdata = DNS_RDATA_INIT;
dns_rdata_soa_t soa;
uint32_t ixfr_serial = query->lookup->ixfr_serial, serial;
isc_result_t result;
int ixfr = query->lookup->rdtype == dns_rdatatype_ixfr;
int axfr = query->lookup->rdtype == dns_rdatatype_axfr;
if (ixfr)
axfr = query->ixfr_axfr;
debug("check_for_more_data()");
/*
* By the time we're in this routine, we know we're doing
* either an AXFR or IXFR. If there's no second_rr_type,
* then we don't yet know which kind of answer we got back
* from the server. Here, we're going to walk through the
* rr's in the message, acting as necessary whenever we hit
* an SOA rr.
*/
query->msg_count++;
query->byte_count += sevent->n;
result = dns_message_firstname(msg, DNS_SECTION_ANSWER);
if (result != ISC_R_SUCCESS) {
puts("; Transfer failed.");
return (1);
}
do {
dns_name_t *name;
name = NULL;
dns_message_currentname(msg, DNS_SECTION_ANSWER,
&name);
for (rdataset = ISC_LIST_HEAD(name->list);
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset, link)) {
result = dns_rdataset_first(rdataset);
if (result != ISC_R_SUCCESS)
continue;
do {
query->rr_count++;
dns_rdata_reset(&rdata);
dns_rdataset_current(rdataset, &rdata);
/*
* If this is the first rr, make sure
* it's an SOA
*/
if ((!query->first_soa_rcvd) &&
(rdata.type != dns_rdatatype_soa)) {
puts("; Transfer failed. "
"Didn't start with SOA answer.");
return (1);
}
if ((!query->second_rr_rcvd) &&
(rdata.type != dns_rdatatype_soa)) {
query->second_rr_rcvd = 1;
query->second_rr_serial = 0;
debug("got the second rr as nonsoa");
axfr = query->ixfr_axfr = 1;
goto next_rdata;
}
/*
* If the record is anything except an SOA
* now, just continue on...
*/
if (rdata.type != dns_rdatatype_soa)
goto next_rdata;
/* Now we have an SOA. Work with it. */
debug("got an SOA");
result = dns_rdata_tostruct_soa(&rdata, &soa);
check_result(result, "dns_rdata_tostruct_soa");
serial = soa.serial;
dns_rdata_freestruct_soa(&soa);
if (!query->first_soa_rcvd) {
query->first_soa_rcvd = 1;
query->first_rr_serial = serial;
debug("this is the first serial %u",
serial);
if (ixfr && isc_serial_ge(ixfr_serial,
serial)) {
debug("got up to date "
"response");
goto doexit;
}
goto next_rdata;
}
if (axfr) {
debug("doing axfr, got second SOA");
goto doexit;
}
if (!query->second_rr_rcvd) {
if (query->first_rr_serial == serial) {
debug("doing ixfr, got "
"empty zone");
goto doexit;
}
debug("this is the second serial %u",
serial);
query->second_rr_rcvd = 1;
query->second_rr_serial = serial;
goto next_rdata;
}
/*
* If we get to this point, we're doing an
* IXFR and have to start really looking
* at serial numbers.
*/
if (query->first_rr_serial == serial) {
debug("got a match for ixfr");
if (!query->first_repeat_rcvd) {
query->first_repeat_rcvd =
1;
goto next_rdata;
}
debug("done with ixfr");
goto doexit;
}
debug("meaningless soa %u", serial);
next_rdata:
result = dns_rdataset_next(rdataset);
} while (result == ISC_R_SUCCESS);
}
result = dns_message_nextname(msg, DNS_SECTION_ANSWER);
} while (result == ISC_R_SUCCESS);
launch_next_query(query, 0);
return (0);
doexit:
dighost_received(sevent->n, &sevent->address, query);
return (1);
}
static void
process_sit(dig_lookup_t *l, dns_message_t *msg,
isc_buffer_t *optbuf, size_t optlen)
{
char bb[256];
isc_buffer_t hexbuf;
size_t len;
const unsigned char *sit;
int copysit;
isc_result_t result;
if (l->sitvalue != NULL) {
isc_buffer_init(&hexbuf, bb, sizeof(bb));
result = isc_hex_decodestring(l->sitvalue, &hexbuf);
check_result(result, "isc_hex_decodestring");
sit = isc_buffer_base(&hexbuf);
len = isc_buffer_usedlength(&hexbuf);
copysit = 0;
} else {
sit = cookie;
len = sizeof(cookie);
copysit = 1;
}
INSIST(msg->sitok == 0 && msg->sitbad == 0);
if (optlen >= len && optlen >= 8U) {
if (timingsafe_bcmp(isc_buffer_current(optbuf), sit, 8) == 0) {
msg->sitok = 1;
} else {
printf(";; Warning: SIT client cookie mismatch\n");
msg->sitbad = 1;
copysit = 0;
}
} else {
printf(";; Warning: SIT bad token (too short)\n");
msg->sitbad = 1;
copysit = 0;
}
if (copysit) {
isc_region_t r;
r.base = isc_buffer_current(optbuf);
r.length = (unsigned int)optlen;
isc_buffer_init(&hexbuf, sitvalue, sizeof(sitvalue));
result = isc_hex_totext(&r, 2, "", &hexbuf);
check_result(result, "isc_hex_totext");
if (isc_buffer_availablelength(&hexbuf) > 0) {
isc_buffer_putuint8(&hexbuf, 0);
l->sitvalue = sitvalue;
}
}
isc_buffer_forward(optbuf, (unsigned int)optlen);
}
static void
process_opt(dig_lookup_t *l, dns_message_t *msg) {
dns_rdata_t rdata;
isc_result_t result;
isc_buffer_t optbuf;
uint16_t optcode, optlen;
dns_rdataset_t *opt = msg->opt;
int seen_cookie = 0;
result = dns_rdataset_first(opt);
if (result == ISC_R_SUCCESS) {
dns_rdata_init(&rdata);
dns_rdataset_current(opt, &rdata);
isc_buffer_init(&optbuf, rdata.data, rdata.length);
isc_buffer_add(&optbuf, rdata.length);
while (isc_buffer_remaininglength(&optbuf) >= 4) {
optcode = isc_buffer_getuint16(&optbuf);
optlen = isc_buffer_getuint16(&optbuf);
switch (optcode) {
case DNS_OPT_COOKIE:
/*
* Only process the first cookie option.
*/
if (seen_cookie) {
isc_buffer_forward(&optbuf, optlen);
break;
}
process_sit(l, msg, &optbuf, optlen);
seen_cookie = 1;
break;
default:
isc_buffer_forward(&optbuf, optlen);
break;
}
}
}
}
static int
ednsvers(dns_rdataset_t *opt) {
return ((opt->ttl >> 16) & 0xff);
}
/*%
* Event handler for recv complete. Perform whatever actions are necessary,
* based on the specifics of the user's request.
*/
static void
recv_done(isc_task_t *task, isc_event_t *event) {
isc_socketevent_t *sevent = NULL;
dig_query_t *query = NULL;
isc_buffer_t *b = NULL;
dns_message_t *msg = NULL;
isc_result_t result;
dig_lookup_t *n, *l;
int docancel = 0;
int match = 1;
unsigned int parseflags;
dns_messageid_t id;
unsigned int msgflags;
int newedns;
UNUSED(task);
INSIST(!free_now);
debug("recv_done()");
recvcount--;
debug("recvcount=%d", recvcount);
INSIST(recvcount >= 0);
query = event->ev_arg;
clock_gettime(CLOCK_MONOTONIC, &query->time_recv);
debug("lookup=%p, query=%p", query->lookup, query);
l = query->lookup;
REQUIRE(event->ev_type == ISC_SOCKEVENT_RECVDONE);
sevent = (isc_socketevent_t *)event;
b = ISC_LIST_HEAD(sevent->bufferlist);
INSIST(b == &query->recvbuf);
ISC_LIST_DEQUEUE(sevent->bufferlist, &query->recvbuf, link);
if ((l->tcp_mode) && (query->timer != NULL))
isc_timer_touch(query->timer);
if ((!l->pending && !l->ns_search_only) || cancel_now) {
debug("no longer pending. Got %s",
isc_result_totext(sevent->result));
query->waiting_connect = 0;
isc_event_free(&event);
clear_query(query);
check_next_lookup(l);
return;
}
if (sevent->result != ISC_R_SUCCESS) {
if (sevent->result == ISC_R_CANCELED) {
debug("in recv cancel handler");
query->waiting_connect = 0;
} else {
printf(";; communications error: %s\n",
isc_result_totext(sevent->result));
if (keep != NULL)
isc_socket_detach(&keep);
isc_socket_detach(&query->sock);
sockcount--;
debug("sockcount=%d", sockcount);
INSIST(sockcount >= 0);
}
if (sevent->result == ISC_R_EOF && l->eoferr == 0U) {
n = requeue_lookup(l, 1);
n->eoferr++;
}
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
}
if (!l->tcp_mode &&
!isc_sockaddr_compare(&sevent->address, &query->sockaddr,
ISC_SOCKADDR_CMPADDR|
ISC_SOCKADDR_CMPPORT|
ISC_SOCKADDR_CMPSCOPE|
ISC_SOCKADDR_CMPSCOPEZERO)) {
char buf1[ISC_SOCKADDR_FORMATSIZE];
char buf2[ISC_SOCKADDR_FORMATSIZE];
struct sockaddr_storage any;
if (isc_sockaddr_pf(&query->sockaddr) == AF_INET)
isc_sockaddr_any(&any);
else
isc_sockaddr_any6(&any);
/*
* We don't expect a match when the packet is
* sent to 0.0.0.0, :: or to a multicast addresses.
* XXXMPA broadcast needs to be handled here as well.
*/
if ((!isc_sockaddr_eqaddr(&query->sockaddr, &any) &&
!isc_sockaddr_ismulticast(&query->sockaddr)) ||
isc_sockaddr_getport(&query->sockaddr) !=
isc_sockaddr_getport(&sevent->address)) {
isc_sockaddr_format(&sevent->address, buf1,
sizeof(buf1));
isc_sockaddr_format(&query->sockaddr, buf2,
sizeof(buf2));
printf(";; reply from unexpected source: %s,"
" expected %s\n", buf1, buf2);
match = 0;
}
}
result = dns_message_peekheader(b, &id, &msgflags);
if (result != ISC_R_SUCCESS || l->sendmsg->id != id) {
match = 0;
if (l->tcp_mode) {
int fail = 1;
if (result == ISC_R_SUCCESS) {
if (!query->first_soa_rcvd ||
query->warn_id)
printf(";; %s: ID mismatch: "
"expected ID %u, got %u\n",
query->first_soa_rcvd ?
"WARNING" : "ERROR",
l->sendmsg->id, id);
if (query->first_soa_rcvd)
fail = 0;
query->warn_id = 0;
} else
printf(";; ERROR: short "
"(< header size) message\n");
if (fail) {
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
}
match = 1;
} else if (result == ISC_R_SUCCESS)
printf(";; Warning: ID mismatch: "
"expected ID %u, got %u\n", l->sendmsg->id, id);
else
printf(";; Warning: short "
"(< header size) message received\n");
}
if (result == ISC_R_SUCCESS && (msgflags & DNS_MESSAGEFLAG_QR) == 0)
printf(";; Warning: query response not set\n");
if (!match)
goto udp_mismatch;
result = dns_message_create(DNS_MESSAGE_INTENTPARSE, &msg);
check_result(result, "dns_message_create");
if (tsigkey != NULL) {
if (l->querysig == NULL) {
debug("getting initial querysig");
result = dns_message_getquerytsig(l->sendmsg,
&l->querysig);
check_result(result, "dns_message_getquerytsig");
}
result = dns_message_setquerytsig(msg, l->querysig);
check_result(result, "dns_message_setquerytsig");
result = dns_message_settsigkey(msg, tsigkey);
check_result(result, "dns_message_settsigkey");
msg->tsigctx = l->tsigctx;
l->tsigctx = NULL;
if (l->msgcounter != 0)
msg->tcp_continuation = 1;
l->msgcounter++;
}
debug("before parse starts");
parseflags = 0;
if (l->besteffort) {
parseflags |= DNS_MESSAGEPARSE_BESTEFFORT;
parseflags |= DNS_MESSAGEPARSE_IGNORETRUNCATION;
}
result = dns_message_parse(msg, b, parseflags);
if (result == DNS_R_RECOVERABLE) {
printf(";; Warning: Message parser reports malformed "
"message packet.\n");
result = ISC_R_SUCCESS;
}
if (result != ISC_R_SUCCESS) {
printf(";; Got bad packet: %s\n", isc_result_totext(result));
hex_dump(b);
query->waiting_connect = 0;
dns_message_destroy(&msg);
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
}
if (msg->counts[DNS_SECTION_QUESTION] != 0) {
match = 1;
for (result = dns_message_firstname(msg, DNS_SECTION_QUESTION);
result == ISC_R_SUCCESS && match;
result = dns_message_nextname(msg, DNS_SECTION_QUESTION)) {
dns_name_t *name = NULL;
dns_rdataset_t *rdataset;
dns_message_currentname(msg, DNS_SECTION_QUESTION,
&name);
for (rdataset = ISC_LIST_HEAD(name->list);
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset, link)) {
if (l->rdtype != rdataset->type ||
l->rdclass != rdataset->rdclass ||
!dns_name_equal(l->name, name)) {
char namestr[DNS_NAME_FORMATSIZE];
char typebuf[DNS_RDATATYPE_FORMATSIZE];
char classbuf[DNS_RDATACLASS_FORMATSIZE];
dns_name_format(name, namestr,
sizeof(namestr));
dns_rdatatype_format(rdataset->type,
typebuf,
sizeof(typebuf));
dns_rdataclass_format(rdataset->rdclass,
classbuf,
sizeof(classbuf));
printf(";; Question section mismatch: "
"got %s/%s/%s\n",
namestr, typebuf, classbuf);
match = 0;
}
}
}
if (!match) {
dns_message_destroy(&msg);
if (l->tcp_mode) {
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
} else
goto udp_mismatch;
}
}
if (msg->rcode == dns_rcode_badvers && msg->opt != NULL &&
(newedns = ednsvers(msg->opt)) < l->edns && l->ednsneg) {
/*
* Add minimum EDNS version required checks here if needed.
*/
if (l->comments)
printf(";; BADVERS, retrying with EDNS version %u.\n",
(unsigned int)newedns);
l->edns = newedns;
n = requeue_lookup(l, 1);
if (l->trace && l->trace_root)
n->rdtype = l->qrdtype;
dns_message_destroy(&msg);
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
}
if ((msg->flags & DNS_MESSAGEFLAG_TC) != 0 &&
!l->ignore && !l->tcp_mode) {
if (l->sitvalue == NULL && l->sit && msg->opt != NULL)
process_opt(l, msg);
if (l->comments)
printf(";; Truncated, retrying in TCP mode.\n");
n = requeue_lookup(l, 1);
n->tcp_mode = 1;
if (l->trace && l->trace_root)
n->rdtype = l->qrdtype;
dns_message_destroy(&msg);
isc_event_free(&event);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
return;
}
if ((msg->rcode == dns_rcode_servfail && !l->servfail_stops) ||
(check_ra && (msg->flags & DNS_MESSAGEFLAG_RA) == 0 && l->recurse))
{
dig_query_t *next = ISC_LIST_NEXT(query, link);
if (l->current_query == query)
l->current_query = NULL;
if (next != NULL) {
debug("sending query %p\n", next);
if (l->tcp_mode)
send_tcp_connect(next);
else
send_udp(next);
}
/*
* If our query is at the head of the list and there
* is no next, we're the only one left, so fall
* through to print the message.
*/
if ((ISC_LIST_HEAD(l->q) != query) ||
(ISC_LIST_NEXT(query, link) != NULL)) {
if (l->comments)
printf(";; Got %s from %s, "
"trying next server\n",
msg->rcode == dns_rcode_servfail ?
"SERVFAIL reply" :
"recursion not available",
query->servname);
clear_query(query);
check_next_lookup(l);
dns_message_destroy(&msg);
isc_event_free(&event);
return;
}
}
if (tsigkey != NULL) {
result = dns_tsig_verify(&query->recvbuf, msg);
if (result != ISC_R_SUCCESS) {
printf(";; Couldn't verify signature: %s\n",
isc_result_totext(result));
validated = 0;
}
l->tsigctx = msg->tsigctx;
msg->tsigctx = NULL;
if (l->querysig != NULL) {
debug("freeing querysig buffer %p", l->querysig);
isc_buffer_free(&l->querysig);
}
result = dns_message_getquerytsig(msg, &l->querysig);
check_result(result,"dns_message_getquerytsig");
}
extrabytes = isc_buffer_remaininglength(b);
debug("after parse");
if (l->doing_xfr && l->xfr_q == NULL) {
l->xfr_q = query;
/*
* Once we are in the XFR message, increase
* the timeout to much longer, so brief network
* outages won't cause the XFR to abort
*/
if (timeout != INT_MAX && query->timer != NULL) {
unsigned int local_timeout;
if (timeout == 0) {
if (l->tcp_mode)
local_timeout = TCP_TIMEOUT * 4;
else
local_timeout = UDP_TIMEOUT * 4;
} else {
if (timeout < (INT_MAX / 4))
local_timeout = timeout * 4;
else
local_timeout = INT_MAX;
}
debug("have local timeout of %d", local_timeout);
l->interval.tv_sec = local_timeout;
l->interval.tv_nsec = 0;
result = isc_timer_reset(query->timer,
&l->interval,
0);
check_result(result, "isc_timer_reset");
}
}
if (l->sitvalue != NULL) {
if (msg->opt == NULL)
printf(";; expected opt record in response\n");
else
process_opt(l, msg);
} else if (l->sit && msg->opt != NULL)
process_opt(l, msg);
if (!l->doing_xfr || l->xfr_q == query) {
if (msg->rcode == dns_rcode_nxdomain &&
(l->origin != NULL || l->need_search)) {
if (!next_origin(query->lookup) || showsearch) {
dighost_printmessage(query, msg, 1);
dighost_received(b->used, &sevent->address, query);
}
} else if (!l->trace && !l->ns_search_only) {
dighost_printmessage(query, msg, 1);
} else if (l->trace) {
int nl = 0;
int count = msg->counts[DNS_SECTION_ANSWER];
debug("in TRACE code");
if (!l->ns_search_only)
dighost_printmessage(query, msg, 1);
l->rdtype = l->qrdtype;
if (l->trace_root || (l->ns_search_only && count > 0)) {
if (!l->trace_root)
l->rdtype = dns_rdatatype_soa;
nl = followup_lookup(msg, query,
DNS_SECTION_ANSWER);
l->trace_root = 0;
} else if (count == 0)
nl = followup_lookup(msg, query,
DNS_SECTION_AUTHORITY);
if (nl == 0)
docancel = 1;
} else {
debug("in NSSEARCH code");
if (l->trace_root) {
/*
* This is the initial NS query.
*/
int nl;
l->rdtype = dns_rdatatype_soa;
nl = followup_lookup(msg, query,
DNS_SECTION_ANSWER);
if (nl == 0)
docancel = 1;
l->trace_root = 0;
usesearch = 0;
} else
dighost_printmessage(query, msg, 1);
}
}
if (l->pending)
debug("still pending.");
if (l->doing_xfr) {
if (query != l->xfr_q) {
dns_message_destroy(&msg);
isc_event_free(&event);
query->waiting_connect = 0;
return;
}
if (!docancel)
docancel = check_for_more_data(query, msg, sevent);
if (docancel) {
dns_message_destroy(&msg);
clear_query(query);
cancel_lookup(l);
check_next_lookup(l);
}
} else {
if (msg->rcode == dns_rcode_noerror || l->origin == NULL) {
dighost_received(b->used, &sevent->address, query);
}
if (!query->lookup->ns_search_only)
query->lookup->pending = 0;
if (!query->lookup->ns_search_only ||
query->lookup->trace_root || docancel) {
dns_message_destroy(&msg);
cancel_lookup(l);
}
clear_query(query);
check_next_lookup(l);
}
if (msg != NULL) {
dns_message_destroy(&msg);
}
isc_event_free(&event);
return;
udp_mismatch:
isc_buffer_invalidate(&query->recvbuf);
isc_buffer_init(&query->recvbuf, query->recvspace, COMMSIZE);
ISC_LIST_ENQUEUE(query->recvlist, &query->recvbuf, link);
result = isc_socket_recvv(query->sock, &query->recvlist, 1,
global_task, recv_done, query);
check_result(result, "isc_socket_recvv");
recvcount++;
isc_event_free(&event);
return;
}
/*%
* Turn a name into an address, using system-supplied routines. This is
* used in looking up server names, etc... and needs to use system-supplied
* routines, since they may be using a non-DNS system for these lookups.
*/
isc_result_t
get_address(char *host, in_port_t myport, struct sockaddr_storage *sockaddr) {
int count;
isc_result_t result;
result = get_addresses(host, myport, sockaddr, 1, &count);
if (result != ISC_R_SUCCESS)
return (result);
INSIST(count == 1);
return (ISC_R_SUCCESS);
}
int
getaddresses(dig_lookup_t *lookup, const char *host, isc_result_t *resultp) {
isc_result_t result;
struct sockaddr_storage sockaddrs[DIG_MAX_ADDRESSES];
int count, i;
dig_server_t *srv;
char tmp[NI_MAXHOST];
result = get_addresses(host, 0, sockaddrs,
DIG_MAX_ADDRESSES, &count);
if (resultp != NULL)
*resultp = result;
if (result != ISC_R_SUCCESS) {
if (resultp == NULL)
fatal("couldn't get address for '%s': %s",
host, isc_result_totext(result));
return (0);
}
for (i = 0; i < count; i++) {
int error;
error = getnameinfo((struct sockaddr *)&sockaddrs[i],
sockaddrs[i].ss_len, tmp, sizeof(tmp), NULL, 0,
NI_NUMERICHOST | NI_NUMERICSERV);
if (error)
fatal("%s", gai_strerror(error));
srv = make_server(tmp, host);
ISC_LIST_APPEND(lookup->my_server_list, srv, link);
}
return (count);
}
/*%
* Initiate either a TCP or UDP lookup
*/
void
do_lookup(dig_lookup_t *lookup) {
dig_query_t *query;
REQUIRE(lookup != NULL);
debug("do_lookup()");
lookup->pending = 1;
query = ISC_LIST_HEAD(lookup->q);
if (query != NULL) {
if (lookup->tcp_mode)
send_tcp_connect(query);
else
send_udp(query);
}
}
/*%
* Start everything in action upon task startup.
*/
void
onrun_callback(isc_task_t *task, isc_event_t *event) {
UNUSED(task);
isc_event_free(&event);
start_lookup();
}
/*%
* Make everything on the lookup queue go away. Mainly used by the
* SIGINT handler.
*/
void
cancel_all(void) {
dig_lookup_t *l, *n;
dig_query_t *q, *nq;
debug("cancel_all()");
if (free_now) {
return;
}
cancel_now = 1;
if (current_lookup != NULL) {
for (q = ISC_LIST_HEAD(current_lookup->q);
q != NULL;
q = nq)
{
nq = ISC_LIST_NEXT(q, link);
debug("canceling pending query %p, belonging to %p",
q, current_lookup);
if (q->sock != NULL)
isc_socket_cancel(q->sock, NULL,
ISC_SOCKCANCEL_ALL);
else
clear_query(q);
}
for (q = ISC_LIST_HEAD(current_lookup->connecting);
q != NULL;
q = nq)
{
nq = ISC_LIST_NEXT(q, clink);
debug("canceling connecting query %p, belonging to %p",
q, current_lookup);
if (q->sock != NULL)
isc_socket_cancel(q->sock, NULL,
ISC_SOCKCANCEL_ALL);
else
clear_query(q);
}
}
l = ISC_LIST_HEAD(lookup_list);
while (l != NULL) {
n = ISC_LIST_NEXT(l, link);
ISC_LIST_DEQUEUE(lookup_list, l, link);
try_clear_lookup(l);
l = n;
}
}
/*%
* Destroy all of the libs we are using, and get everything ready for a
* clean shutdown.
*/
void
destroy_libs(void) {
if (keep != NULL)
isc_socket_detach(&keep);
debug("destroy_libs()");
if (global_task != NULL) {
debug("freeing task");
isc_task_detach(&global_task);
}
/*
* The taskmgr_destroy() call blocks until all events are cleared
* from the task.
*/
if (taskmgr != NULL) {
debug("freeing taskmgr");
isc_taskmgr_destroy(&taskmgr);
}
REQUIRE(sockcount == 0);
REQUIRE(recvcount == 0);
REQUIRE(sendcount == 0);
INSIST(ISC_LIST_HEAD(lookup_list) == NULL);
INSIST(current_lookup == NULL);
INSIST(!free_now);
free_now = 1;
lwres_conf_clear(lwconf);
flush_server_list();
clear_searchlist();
if (socketmgr != NULL) {
debug("freeing socketmgr");
isc_socketmgr_destroy(&socketmgr);
}
if (timermgr != NULL) {
debug("freeing timermgr");
isc_timermgr_destroy(&timermgr);
}
if (tsigkey != NULL) {
debug("freeing key %p", tsigkey);
dns_tsigkey_detach(&tsigkey);
}
if (namebuf != NULL)
isc_buffer_free(&namebuf);
if (is_dst_up) {
debug("destroy DST lib");
dst_lib_destroy();
is_dst_up = 0;
}
debug("Removing log context");
isc_log_destroy(&lctx);
}
int64_t
uelapsed(const struct timespec *t1, const struct timespec *t2)
{
struct timespec diff, zero = {0, 0};
struct timeval tv;
timespecsub(t1, t2, &diff);
if (timespeccmp(&diff, &zero, <=))
return 0;
TIMESPEC_TO_TIMEVAL(&tv, &diff);
return (tv.tv_sec * 1000000 + tv.tv_usec);
}
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