nslookup: add openwrt / lede version
Needs work on size reduction function old new delta nslookup_main 114 2363 +2249 parse_reply - 1022 +1022 add_ns - 663 +663 ns_parserr - 486 +486 ns_initparse - 184 +184 ns_skiprr - 117 +117 add_query - 95 +95 qtypes - 80 +80 rcodes - 68 +68 dn_skipname - 58 +58 ns_name_uncompress - 56 +56 ns_get16 - 13 +13 v4_mapped - 12 +12 ns_get32 - 9 +9 res_init 3 - -3 __res_state 6 - -6 xmalloc_sockaddr2hostonly_noport 10 - -10 gai_strerror 47 - -47 set_default_dns 95 - -95 print_host 199 - -199 static.res 512 - -512 ------------------------------------------------------------------------------ (add/remove: 15/10 grow/shrink: 1/0 up/down: 5112/-872) Total: 4240 bytes text data bss dec hex filename 921944 555 6252 928751 e2bef busybox_old 927375 555 5740 933670 e3f26 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
parent
43dd006222
commit
0dd3be8c09
@ -1,20 +1,20 @@
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/* vi: set sw=4 ts=4: */
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/*
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* Mini nslookup implementation for busybox
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*
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* Copyright (C) 1999,2000 by Lineo, inc. and John Beppu
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* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
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*
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* Correct default name server display and explicit name server option
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* added by Ben Zeckel <bzeckel@hmc.edu> June 2001
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*
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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*/
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//config:config NSLOOKUP
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//config: bool "nslookup (4.5 kb)"
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//config: default y
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//config: help
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//config: nslookup is a tool to query Internet name servers.
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//config:
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//config:config NSLOOKUP_BIG
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//config: bool "Use internal resolver code instead of libc"
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//config: depends on NSLOOKUP
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//config: default y
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//config:
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//config:config FEATURE_NSLOOKUP_LONG_OPTIONS
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//config: bool "Enable long options"
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//config: default y
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//config: depends on NSLOOKUP_BIG && LONG_OPTS
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//applet:IF_NSLOOKUP(APPLET(nslookup, BB_DIR_USR_BIN, BB_SUID_DROP))
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@ -35,7 +35,26 @@
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//usage: "Address: 127.0.0.1\n"
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#include <resolv.h>
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#include <net/if.h> /* for IFNAMSIZ */
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//#include <arpa/inet.h>
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//#include <netdb.h>
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#include "libbb.h"
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#include "common_bufsiz.h"
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#if !ENABLE_NSLOOKUP_BIG
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/*
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* Mini nslookup implementation for busybox
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*
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* Copyright (C) 1999,2000 by Lineo, inc. and John Beppu
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* Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
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*
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* Correct default name server display and explicit name server option
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* added by Ben Zeckel <bzeckel@hmc.edu> June 2001
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*
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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*/
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/*
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* I'm only implementing non-interactive mode;
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@ -207,3 +226,881 @@ int nslookup_main(int argc, char **argv)
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return print_host(argv[1], "Name:");
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}
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#else /****** A version from LEDE / OpenWRT ******/
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/*
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* musl compatible nslookup
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*
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* Copyright (C) 2017 Jo-Philipp Wich <jo@mein.io>
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*
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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#if 0
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# define dbg(...) fprintf(stderr, __VA_ARGS__)
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#else
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# define dbg(...) ((void)0)
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#endif
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struct ns {
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const char *name;
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len_and_sockaddr addr;
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int failures;
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int replies;
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};
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struct query {
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const char *name;
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size_t qlen, rlen;
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unsigned char query[512], reply[512];
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unsigned long latency;
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int rcode, n_ns;
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};
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static const struct {
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int type;
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const char *name;
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} qtypes[] = {
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{ ns_t_soa, "SOA" },
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{ ns_t_ns, "NS" },
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{ ns_t_a, "A" },
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#if ENABLE_FEATURE_IPV6
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{ ns_t_aaaa, "AAAA" },
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#endif
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{ ns_t_cname, "CNAME" },
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{ ns_t_mx, "MX" },
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{ ns_t_txt, "TXT" },
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{ ns_t_ptr, "PTR" },
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{ ns_t_any, "ANY" },
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{ }
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};
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static const char *const rcodes[] = {
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"NOERROR",
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"FORMERR",
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"SERVFAIL",
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"NXDOMAIN",
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"NOTIMP",
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"REFUSED",
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"YXDOMAIN",
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"YXRRSET",
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"NXRRSET",
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"NOTAUTH",
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"NOTZONE",
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"RESERVED11",
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"RESERVED12",
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"RESERVED13",
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"RESERVED14",
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"RESERVED15",
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"BADVERS"
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};
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#if ENABLE_FEATURE_IPV6
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static const char v4_mapped[] = { 0,0,0,0,0,0,0,0,0,0,0xff,0xff };
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#endif
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struct globals {
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unsigned default_port;
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unsigned default_retry;
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unsigned default_timeout;
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} FIX_ALIASING;
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#define G (*(struct globals*)bb_common_bufsiz1)
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#define INIT_G() do { \
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setup_common_bufsiz(); \
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G.default_port = 53; \
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G.default_retry = 2; \
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G.default_timeout = 5; \
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} while (0)
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static int
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parse_reply(const unsigned char *msg, size_t len, int *bb_style_counter)
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{
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ns_msg handle;
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ns_rr rr;
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int i, n, rdlen;
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const char *format = NULL;
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char astr[INET6_ADDRSTRLEN], dname[MAXDNAME];
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const unsigned char *cp;
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if (ns_initparse(msg, len, &handle) != 0) {
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//fprintf(stderr, "Unable to parse reply: %s\n", strerror(errno));
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return -1;
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}
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for (i = 0; i < ns_msg_count(handle, ns_s_an); i++) {
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if (ns_parserr(&handle, ns_s_an, i, &rr) != 0) {
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//fprintf(stderr, "Unable to parse resource record: %s\n", strerror(errno));
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return -1;
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}
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if (bb_style_counter && *bb_style_counter == 1)
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printf("Name: %s\n", ns_rr_name(rr));
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rdlen = ns_rr_rdlen(rr);
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switch (ns_rr_type(rr))
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{
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case ns_t_a:
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if (rdlen != 4) {
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//fprintf(stderr, "Unexpected A record length\n");
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return -1;
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}
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inet_ntop(AF_INET, ns_rr_rdata(rr), astr, sizeof(astr));
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if (bb_style_counter)
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printf("Address %d: %s\n", (*bb_style_counter)++, astr);
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else
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printf("Name:\t%s\nAddress: %s\n", ns_rr_name(rr), astr);
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break;
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#if ENABLE_FEATURE_IPV6
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case ns_t_aaaa:
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if (rdlen != 16) {
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//fprintf(stderr, "Unexpected AAAA record length\n");
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return -1;
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}
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inet_ntop(AF_INET6, ns_rr_rdata(rr), astr, sizeof(astr));
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if (bb_style_counter)
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printf("Address %d: %s\n", (*bb_style_counter)++, astr);
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else
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printf("%s\thas AAAA address %s\n", ns_rr_name(rr), astr);
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break;
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#endif
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case ns_t_ns:
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if (!format)
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format = "%s\tnameserver = %s\n";
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/* fall through */
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case ns_t_cname:
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if (!format)
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format = "%s\tcanonical name = %s\n";
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/* fall through */
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case ns_t_ptr:
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if (!format)
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format = "%s\tname = %s\n";
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if (ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
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ns_rr_rdata(rr), dname, sizeof(dname)) < 0) {
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//fprintf(stderr, "Unable to uncompress domain: %s\n", strerror(errno));
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return -1;
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}
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printf(format, ns_rr_name(rr), dname);
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break;
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case ns_t_mx:
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if (rdlen < 2) {
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fprintf(stderr, "MX record too short\n");
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return -1;
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}
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n = ns_get16(ns_rr_rdata(rr));
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if (ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
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ns_rr_rdata(rr) + 2, dname, sizeof(dname)) < 0) {
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//fprintf(stderr, "Cannot uncompress MX domain: %s\n", strerror(errno));
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return -1;
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}
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printf("%s\tmail exchanger = %d %s\n", ns_rr_name(rr), n, dname);
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break;
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case ns_t_txt:
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if (rdlen < 1) {
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//fprintf(stderr, "TXT record too short\n");
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return -1;
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}
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n = *(unsigned char *)ns_rr_rdata(rr);
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if (n > 0) {
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memset(dname, 0, sizeof(dname));
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memcpy(dname, ns_rr_rdata(rr) + 1, n);
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printf("%s\ttext = \"%s\"\n", ns_rr_name(rr), dname);
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}
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break;
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case ns_t_soa:
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if (rdlen < 20) {
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//fprintf(stderr, "SOA record too short\n");
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return -1;
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}
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printf("%s\n", ns_rr_name(rr));
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cp = ns_rr_rdata(rr);
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n = ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
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cp, dname, sizeof(dname));
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if (n < 0) {
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//fprintf(stderr, "Unable to uncompress domain: %s\n", strerror(errno));
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return -1;
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}
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printf("\torigin = %s\n", dname);
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cp += n;
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n = ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
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cp, dname, sizeof(dname));
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if (n < 0) {
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//fprintf(stderr, "Unable to uncompress domain: %s\n", strerror(errno));
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return -1;
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}
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printf("\tmail addr = %s\n", dname);
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cp += n;
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printf("\tserial = %lu\n", ns_get32(cp));
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cp += 4;
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printf("\trefresh = %lu\n", ns_get32(cp));
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cp += 4;
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printf("\tretry = %lu\n", ns_get32(cp));
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cp += 4;
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printf("\texpire = %lu\n", ns_get32(cp));
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cp += 4;
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printf("\tminimum = %lu\n", ns_get32(cp));
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break;
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default:
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break;
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}
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}
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return i;
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}
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static int parse_nsaddr(const char *addrstr, len_and_sockaddr *lsa)
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{
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char *hash;
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unsigned port = G.default_port;
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IF_FEATURE_IPV6(unsigned scope;)
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dbg("%s: addrstr:'%s'\n", __func__, addrstr);
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hash = strchr(addrstr, '#');
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if (hash) {
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*hash++ = '\0';
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port = bb_strtou(hash, NULL, 10);
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if (errno || port > 65535) {
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errno = EINVAL;
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return -1;
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}
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}
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#if ENABLE_FEATURE_IPV6
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scope = 0;
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hash = strchr(addrstr, '%');
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if (hash) {
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char ifname[IFNAMSIZ];
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int i;
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hash++;
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for (i = 0; hash[i] != '\0' && hash[i] != '#'; i++) {
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if (i >= IFNAMSIZ) {
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errno = ENODEV;
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return -1;
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}
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ifname[i] = hash[i];
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}
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ifname[i] = '\0';
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scope = if_nametoindex(ifname);
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if (scope == 0) {
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errno = ENODEV;
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return -1;
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}
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}
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if (inet_pton(AF_INET6, addrstr, &lsa->u.sin6.sin6_addr)) {
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lsa->u.sin6.sin6_family = AF_INET6;
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lsa->u.sin6.sin6_port = htons(port);
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lsa->u.sin6.sin6_scope_id = scope;
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lsa->len = sizeof(lsa->u.sin6);
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return 0;
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}
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#endif
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if (inet_pton(AF_INET, addrstr, &lsa->u.sin.sin_addr)) {
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lsa->u.sin.sin_family = AF_INET;
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lsa->u.sin.sin_port = htons(port);
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lsa->len = sizeof(lsa->u.sin);
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return 0;
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}
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errno = EINVAL;
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return -1;
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}
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static char *make_ptr(char resbuf[80], const char *addrstr)
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{
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unsigned char addr[16];
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int i;
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#if ENABLE_FEATURE_IPV6
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if (inet_pton(AF_INET6, addrstr, addr)) {
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if (memcmp(addr, v4_mapped, 12) != 0) {
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char *ptr = resbuf;
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for (i = 0; i < 16; i++) {
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*ptr++ = 0x20 | bb_hexdigits_upcase[(unsigned char)addr[15 - i] & 0xf];
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*ptr++ = '.';
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*ptr++ = 0x20 | bb_hexdigits_upcase[(unsigned char)addr[15 - i] >> 4];
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*ptr++ = '.';
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}
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strcpy(ptr, "ip6.arpa");
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}
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else {
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sprintf(resbuf, "%u.%u.%u.%u.in-addr.arpa",
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addr[15], addr[14], addr[13], addr[12]);
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}
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return resbuf;
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}
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#endif
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if (inet_pton(AF_INET, addrstr, addr)) {
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sprintf(resbuf, "%u.%u.%u.%u.in-addr.arpa",
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addr[3], addr[2], addr[1], addr[0]);
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return resbuf;
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}
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return NULL;
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}
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#if ENABLE_FEATURE_IPV6
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static void to_v4_mapped(len_and_sockaddr *a)
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{
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if (a->u.sa.sa_family != AF_INET)
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return;
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/* Order is important */
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//FIXME: port?
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memcpy(a->u.sin6.sin6_addr.s6_addr + 12, &a->u.sin.sin_addr, 4);
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memcpy(a->u.sin6.sin6_addr.s6_addr, v4_mapped, 12);
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a->u.sin6.sin6_family = AF_INET6;
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a->u.sin6.sin6_flowinfo = 0;
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a->u.sin6.sin6_scope_id = 0;
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a->len = sizeof(a->u.sin6);
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}
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#endif
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/*
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* Function logic borrowed & modified from musl libc, res_msend.c
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*/
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static int send_queries(struct ns *ns, int n_ns, struct query *queries, int n_queries)
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{
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int fd;
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int timeout = G.default_timeout * 1000, retry_interval, servfail_retry = 0;
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len_and_sockaddr from = { };
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int recvlen = 0;
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int n_replies = 0;
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struct pollfd pfd;
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unsigned long t0, t1, t2;
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int nn, qn, next_query = 0;
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from.u.sa.sa_family = AF_INET;
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from.len = sizeof(from.u.sin);
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#if ENABLE_FEATURE_IPV6
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for (nn = 0; nn < n_ns; nn++) {
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if (ns[nn].addr.u.sa.sa_family == AF_INET6) {
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from.u.sa.sa_family = AF_INET6;
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from.len = sizeof(from.u.sin6);
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break;
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}
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}
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#endif
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/* Get local address and open/bind a socket */
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#if ENABLE_FEATURE_IPV6
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fd = socket(from.u.sa.sa_family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
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/* Handle case where system lacks IPv6 support */
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if (fd < 0) {
|
||||
if (from.u.sa.sa_family != AF_INET6 || errno != EAFNOSUPPORT)
|
||||
bb_perror_msg_and_die("socket");
|
||||
fd = xsocket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
|
||||
from.u.sa.sa_family = AF_INET;
|
||||
}
|
||||
#else
|
||||
fd = xsocket(from.u.sa.sa_family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
|
||||
#endif
|
||||
xbind(fd, &from.u.sa, from.len);
|
||||
|
||||
#if ENABLE_FEATURE_IPV6
|
||||
/* Convert any IPv4 addresses in a mixed environment to v4-mapped */
|
||||
if (from.u.sa.sa_family == AF_INET6) {
|
||||
setsockopt_1(fd, IPPROTO_IPV6, IPV6_V6ONLY);
|
||||
for (nn = 0; nn < n_ns; nn++)
|
||||
to_v4_mapped(&ns[nn].addr);
|
||||
}
|
||||
#endif
|
||||
|
||||
pfd.fd = fd;
|
||||
pfd.events = POLLIN;
|
||||
retry_interval = timeout / G.default_retry;
|
||||
t0 = t2 = monotonic_ms();
|
||||
t1 = t2 - retry_interval;
|
||||
|
||||
for (; t2 - t0 < timeout; t2 = monotonic_ms()) {
|
||||
if (t2 - t1 >= retry_interval) {
|
||||
for (qn = 0; qn < n_queries; qn++) {
|
||||
if (queries[qn].rlen)
|
||||
continue;
|
||||
|
||||
for (nn = 0; nn < n_ns; nn++) {
|
||||
sendto(fd, queries[qn].query, queries[qn].qlen,
|
||||
MSG_NOSIGNAL, &ns[nn].addr.u.sa, ns[nn].addr.len);
|
||||
}
|
||||
}
|
||||
|
||||
t1 = t2;
|
||||
servfail_retry = 2 * n_queries;
|
||||
}
|
||||
|
||||
/* Wait for a response, or until time to retry */
|
||||
if (poll(&pfd, 1, t1 + retry_interval - t2) <= 0)
|
||||
continue;
|
||||
|
||||
while (1) {
|
||||
recvlen = recvfrom(fd, queries[next_query].reply,
|
||||
sizeof(queries[next_query].reply), 0,
|
||||
&from.u.sa, &from.len
|
||||
);
|
||||
|
||||
/* read error */
|
||||
if (recvlen < 0)
|
||||
break;
|
||||
|
||||
/* Ignore non-identifiable packets */
|
||||
if (recvlen < 4)
|
||||
continue;
|
||||
|
||||
/* Ignore replies from addresses we didn't send to */
|
||||
for (nn = 0; nn < n_ns; nn++)
|
||||
if (memcmp(&from.u.sa, &ns[nn].addr.u.sa, from.len) == 0)
|
||||
break;
|
||||
|
||||
if (nn >= n_ns)
|
||||
continue;
|
||||
|
||||
/* Find which query this answer goes with, if any */
|
||||
for (qn = next_query; qn < n_queries; qn++)
|
||||
if (memcmp(queries[next_query].reply, queries[qn].query, 2) == 0)
|
||||
break;
|
||||
|
||||
if (qn >= n_queries || queries[qn].rlen)
|
||||
continue;
|
||||
|
||||
queries[qn].rcode = queries[next_query].reply[3] & 15;
|
||||
queries[qn].latency = monotonic_ms() - t0;
|
||||
queries[qn].n_ns = nn;
|
||||
|
||||
ns[nn].replies++;
|
||||
|
||||
/* Only accept positive or negative responses;
|
||||
* retry immediately on server failure, and ignore
|
||||
* all other codes such as refusal. */
|
||||
switch (queries[qn].rcode) {
|
||||
case 0:
|
||||
case 3:
|
||||
break;
|
||||
|
||||
case 2:
|
||||
if (servfail_retry && servfail_retry--) {
|
||||
ns[nn].failures++;
|
||||
sendto(fd, queries[qn].query, queries[qn].qlen,
|
||||
MSG_NOSIGNAL, &ns[nn].addr.u.sa, ns[nn].addr.len);
|
||||
}
|
||||
/* fall through */
|
||||
|
||||
default:
|
||||
continue;
|
||||
}
|
||||
|
||||
/* Store answer */
|
||||
n_replies++;
|
||||
|
||||
queries[qn].rlen = recvlen;
|
||||
|
||||
if (qn == next_query) {
|
||||
while (next_query < n_queries) {
|
||||
if (!queries[next_query].rlen)
|
||||
break;
|
||||
|
||||
next_query++;
|
||||
}
|
||||
}
|
||||
else {
|
||||
memcpy(queries[qn].reply, queries[next_query].reply, recvlen);
|
||||
}
|
||||
|
||||
if (next_query >= n_queries)
|
||||
return n_replies;
|
||||
}
|
||||
}
|
||||
|
||||
return n_replies;
|
||||
}
|
||||
|
||||
///FIXME: use standard lsa = xhost2sockaddr(host, port) instead
|
||||
|
||||
static struct ns *add_ns(struct ns **ns, int *n_ns, const char *addr)
|
||||
{
|
||||
char portstr[sizeof("65535")], *p;
|
||||
len_and_sockaddr a = { };
|
||||
struct ns *tmp;
|
||||
struct addrinfo *ai, *aip, hints = {
|
||||
.ai_flags = AI_NUMERICSERV,
|
||||
.ai_socktype = SOCK_DGRAM
|
||||
};
|
||||
|
||||
dbg("%s: addr:'%s'\n", __func__, addr);
|
||||
|
||||
if (parse_nsaddr(addr, &a)) {
|
||||
/* Maybe we got a domain name, attempt to resolve it using the standard
|
||||
* resolver routines */
|
||||
|
||||
p = strchr(addr, '#');
|
||||
snprintf(portstr, sizeof(portstr), "%hu",
|
||||
(unsigned short)(p ? strtoul(p, NULL, 10) : G.default_port));
|
||||
|
||||
if (!getaddrinfo(addr, portstr, &hints, &ai)) {
|
||||
for (aip = ai; aip; aip = aip->ai_next) {
|
||||
if (aip->ai_addr->sa_family != AF_INET &&
|
||||
aip->ai_addr->sa_family != AF_INET6)
|
||||
continue;
|
||||
|
||||
#if ! ENABLE_FEATURE_IPV6
|
||||
if (aip->ai_addr->sa_family != AF_INET)
|
||||
continue;
|
||||
#endif
|
||||
|
||||
tmp = realloc(*ns, sizeof(**ns) * (*n_ns + 1));
|
||||
|
||||
if (!tmp)
|
||||
return NULL;
|
||||
|
||||
*ns = tmp;
|
||||
|
||||
(*ns)[*n_ns].name = addr;
|
||||
(*ns)[*n_ns].replies = 0;
|
||||
(*ns)[*n_ns].failures = 0;
|
||||
(*ns)[*n_ns].addr.len = aip->ai_addrlen;
|
||||
|
||||
memcpy(&(*ns)[*n_ns].addr.u.sa, aip->ai_addr, aip->ai_addrlen);
|
||||
|
||||
(*n_ns)++;
|
||||
}
|
||||
|
||||
freeaddrinfo(ai);
|
||||
|
||||
return &(*ns)[*n_ns];
|
||||
}
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
tmp = xrealloc(*ns, sizeof(**ns) * (*n_ns + 1));
|
||||
*ns = tmp;
|
||||
|
||||
(*ns)[*n_ns].addr = a;
|
||||
(*ns)[*n_ns].name = addr;
|
||||
(*ns)[*n_ns].replies = 0;
|
||||
(*ns)[*n_ns].failures = 0;
|
||||
|
||||
return &(*ns)[(*n_ns)++];
|
||||
}
|
||||
|
||||
static int parse_resolvconf(struct ns **ns, int *n_ns)
|
||||
{
|
||||
int prev_n_ns = *n_ns;
|
||||
FILE *resolv;
|
||||
|
||||
resolv = fopen("/etc/resolv.conf", "r");
|
||||
if (resolv) {
|
||||
char line[128], *p;
|
||||
|
||||
while (fgets(line, sizeof(line), resolv)) {
|
||||
p = strtok(line, " \t\n");
|
||||
|
||||
if (!p || strcmp(p, "nameserver") != 0)
|
||||
continue;
|
||||
|
||||
p = strtok(NULL, " \t\n");
|
||||
|
||||
if (!p)
|
||||
continue;
|
||||
|
||||
if (!add_ns(ns, n_ns, xstrdup(p))) {
|
||||
free(p);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
fclose(resolv);
|
||||
}
|
||||
|
||||
return *n_ns - prev_n_ns;
|
||||
}
|
||||
|
||||
static struct query *add_query(struct query **queries, int *n_queries,
|
||||
int type, const char *dname)
|
||||
{
|
||||
struct query *new_q;
|
||||
int pos;
|
||||
ssize_t qlen;
|
||||
|
||||
pos = *n_queries;
|
||||
*n_queries = pos + 1;
|
||||
*queries = new_q = xrealloc(*queries, sizeof(**queries) * (pos + 1));
|
||||
|
||||
dbg("new query#%u type %u for '%s'\n", pos, type, dname);
|
||||
new_q += pos;
|
||||
memset(new_q, 0, sizeof(*new_q));
|
||||
|
||||
qlen = res_mkquery(QUERY, dname, C_IN, type, NULL, 0, NULL,
|
||||
new_q->query, sizeof(new_q->query));
|
||||
|
||||
new_q->qlen = qlen;
|
||||
new_q->name = dname;
|
||||
|
||||
return new_q;
|
||||
}
|
||||
|
||||
//FIXME: use xmalloc_sockaddr2dotted[_noport]() instead of sal2str()
|
||||
|
||||
#define SIZEOF_SAL2STR_BUF (INET6_ADDRSTRLEN + 1 + IFNAMSIZ + 1 + 5 + 1)
|
||||
static char *sal2str(char buf[SIZEOF_SAL2STR_BUF], len_and_sockaddr *a)
|
||||
{
|
||||
char *p = buf;
|
||||
|
||||
#if ENABLE_FEATURE_IPV6
|
||||
if (a->u.sa.sa_family == AF_INET6) {
|
||||
inet_ntop(AF_INET6, &a->u.sin6.sin6_addr, buf, SIZEOF_SAL2STR_BUF);
|
||||
p += strlen(p);
|
||||
|
||||
if (a->u.sin6.sin6_scope_id) {
|
||||
if (if_indextoname(a->u.sin6.sin6_scope_id, p + 1)) {
|
||||
*p++ = '%';
|
||||
p += strlen(p);
|
||||
}
|
||||
}
|
||||
} else
|
||||
#endif
|
||||
{
|
||||
inet_ntop(AF_INET, &a->u.sin.sin_addr, buf, SIZEOF_SAL2STR_BUF);
|
||||
p += strlen(p);
|
||||
}
|
||||
|
||||
sprintf(p, "#%hu", ntohs(a->u.sin.sin_port));
|
||||
|
||||
return buf;
|
||||
}
|
||||
|
||||
int nslookup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
||||
int nslookup_main(int argc UNUSED_PARAM, char **argv)
|
||||
{
|
||||
struct ns *ns;
|
||||
struct query *queries;
|
||||
llist_t *type_strings;
|
||||
int n_ns, n_queries;
|
||||
int bb_style_counter = 0;
|
||||
unsigned types;
|
||||
int rc;
|
||||
int opts;
|
||||
enum {
|
||||
OPT_stats = (1 << 4),
|
||||
};
|
||||
|
||||
INIT_G();
|
||||
|
||||
type_strings = NULL;
|
||||
#if ENABLE_FEATURE_NSLOOKUP_LONG_OPTIONS
|
||||
opts = getopt32long(argv, "^"
|
||||
"+" /* '+': stop at first non-option (why?) */
|
||||
"q:*p:+r:+t:+s"
|
||||
"\0"
|
||||
"-1:q::", /* minimum 1 arg, -q is a list */
|
||||
"type\0" Required_argument "q"
|
||||
"querytype\0" Required_argument "q"
|
||||
"port\0" Required_argument "p"
|
||||
"retry\0" Required_argument "r"
|
||||
"timeout\0" Required_argument "t"
|
||||
"stats\0" No_argument "s",
|
||||
&type_strings, &G.default_port,
|
||||
&G.default_retry, &G.default_timeout
|
||||
);
|
||||
#else
|
||||
opts = getopt32(argv, "^"
|
||||
"+" /* '+': stop at first non-option (why?) */
|
||||
"q:*p:+r:+t:+s"
|
||||
"\0"
|
||||
"-1:q::", /* minimum 1 arg, -q is a list */
|
||||
&type_strings, &G.default_port,
|
||||
&G.default_retry, &G.default_timeout
|
||||
);
|
||||
#endif
|
||||
if (G.default_port > 65535)
|
||||
bb_error_msg_and_die("invalid server port");
|
||||
if (G.default_retry == 0)
|
||||
bb_error_msg_and_die("invalid retry value");
|
||||
if (G.default_timeout == 0)
|
||||
bb_error_msg_and_die("invalid timeout value");
|
||||
|
||||
types = 0;
|
||||
while (type_strings) {
|
||||
int c;
|
||||
char *ptr, *chr;
|
||||
|
||||
ptr = llist_pop(&type_strings);
|
||||
|
||||
/* skip leading text, e.g. when invoked with -querytype=AAAA */
|
||||
chr = strchr(ptr, '=');
|
||||
if (chr)
|
||||
ptr = chr + 1;
|
||||
|
||||
for (c = 0;; c++) {
|
||||
if (!qtypes[c].name)
|
||||
bb_error_msg_and_die("invalid query type \"%s\"", ptr);
|
||||
if (strcmp(qtypes[c].name, ptr) == 0)
|
||||
break;
|
||||
}
|
||||
|
||||
types |= (1 << c);
|
||||
}
|
||||
|
||||
argv += optind;
|
||||
|
||||
n_queries = 0;
|
||||
queries = NULL;
|
||||
do {
|
||||
/* No explicit type given, guess query type.
|
||||
* If we can convert the domain argument into a ptr (means that
|
||||
* inet_pton() could read it) we assume a PTR request, else
|
||||
* we issue A+AAAA queries and switch to an output format
|
||||
* mimicking the one of the traditional nslookup applet. */
|
||||
if (types == 0) {
|
||||
char *ptr;
|
||||
char buf80[80];
|
||||
|
||||
ptr = make_ptr(buf80, *argv);
|
||||
|
||||
if (ptr) {
|
||||
add_query(&queries, &n_queries, T_PTR, ptr);
|
||||
}
|
||||
else {
|
||||
bb_style_counter = 1;
|
||||
add_query(&queries, &n_queries, T_A, *argv);
|
||||
#if ENABLE_FEATURE_IPV6
|
||||
add_query(&queries, &n_queries, T_AAAA, *argv);
|
||||
#endif
|
||||
}
|
||||
}
|
||||
else {
|
||||
int c;
|
||||
for (c = 0; qtypes[c].name; c++) {
|
||||
if (types & (1 << c))
|
||||
add_query(&queries, &n_queries, qtypes[c].type,
|
||||
*argv);
|
||||
}
|
||||
}
|
||||
argv++;
|
||||
} while (argv[0] && argv[1]);
|
||||
|
||||
/* Use given DNS server if present */
|
||||
n_ns = 0;
|
||||
ns = NULL;
|
||||
if (argv[0]) {
|
||||
if (!add_ns(&ns, &n_ns, argv[0]))
|
||||
bb_error_msg_and_die("invalid NS server address \"%s\"", argv[0]);
|
||||
} else {
|
||||
parse_resolvconf(&ns, &n_ns);
|
||||
/* Fall back to localhost if we could not find NS in resolv.conf */
|
||||
if (n_ns == 0)
|
||||
add_ns(&ns, &n_ns, "127.0.0.1");
|
||||
}
|
||||
|
||||
for (rc = 0; rc < n_ns; rc++) {
|
||||
int c = send_queries(&ns[rc], 1, queries, n_queries);
|
||||
if (c < 0)
|
||||
bb_perror_msg_and_die("can't send queries");
|
||||
if (c > 0)
|
||||
break;
|
||||
rc++;
|
||||
if (rc >= n_ns) {
|
||||
fprintf(stderr,
|
||||
";; connection timed out; no servers could be reached\n\n");
|
||||
return EXIT_FAILURE;
|
||||
}
|
||||
}
|
||||
|
||||
printf("Server:\t\t%s\n", ns[rc].name);
|
||||
{
|
||||
char buf[SIZEOF_SAL2STR_BUF];
|
||||
printf("Address:\t%s\n", sal2str(buf, &ns[rc].addr));
|
||||
}
|
||||
if (opts & OPT_stats) {
|
||||
printf("Replies:\t%d\n", ns[rc].replies);
|
||||
printf("Failures:\t%d\n", ns[rc].failures);
|
||||
}
|
||||
printf("\n");
|
||||
|
||||
for (rc = 0; rc < n_queries; rc++) {
|
||||
int c;
|
||||
|
||||
if (opts & OPT_stats) {
|
||||
printf("Query #%d completed in %lums:\n", rc, queries[rc].latency);
|
||||
}
|
||||
|
||||
if (queries[rc].rcode != 0) {
|
||||
printf("** server can't find %s: %s\n", queries[rc].name,
|
||||
rcodes[queries[rc].rcode]);
|
||||
continue;
|
||||
}
|
||||
|
||||
c = 0;
|
||||
|
||||
if (queries[rc].rlen) {
|
||||
HEADER *header;
|
||||
|
||||
if (!bb_style_counter) {
|
||||
header = (HEADER *)queries[rc].reply;
|
||||
if (!header->aa)
|
||||
printf("Non-authoritative answer:\n");
|
||||
c = parse_reply(queries[rc].reply, queries[rc].rlen, NULL);
|
||||
}
|
||||
else {
|
||||
c = parse_reply(queries[rc].reply, queries[rc].rlen,
|
||||
&bb_style_counter);
|
||||
}
|
||||
}
|
||||
|
||||
if (c == 0)
|
||||
printf("*** Can't find %s: No answer\n", queries[rc].name);
|
||||
else if (c < 0)
|
||||
printf("*** Can't find %s: Parse error\n", queries[rc].name);
|
||||
|
||||
if (!bb_style_counter)
|
||||
printf("\n");
|
||||
}
|
||||
|
||||
if (ENABLE_FEATURE_CLEAN_UP) {
|
||||
free(ns);
|
||||
if (n_queries)
|
||||
free(queries);
|
||||
}
|
||||
|
||||
return EXIT_SUCCESS;
|
||||
}
|
||||
|
||||
#endif
|
||||
|
||||
Loading…
Reference in New Issue
Block a user