[source] busybox: add musl compatible nslookup replacement
LEDE Commits
lede-commits at lists.infradead.org
Sat Apr 15 09:19:50 PDT 2017
jow pushed a commit to source.git, branch lede-17.01:
https://git.lede-project.org/1d76542ccafe533bfef20074b115dbed4549c986
commit 1d76542ccafe533bfef20074b115dbed4549c986
Author: Jo-Philipp Wich <jo at mein.io>
AuthorDate: Tue Mar 14 22:38:59 2017 +0100
busybox: add musl compatible nslookup replacement
Add an alternative nslookup applet implementation which is compatible with
musl libc wrt. name server selection and which supports a number of additional
features such as query type selection.
Fixes #155, #217
Signed-off-by: Jo-Philipp Wich <jo at mein.io>
---
package/utils/busybox/Config-defaults.in | 3 +
package/utils/busybox/config/networking/Config.in | 14 +
.../busybox/patches/230-add_nslookup_lede.patch | 914 +++++++++++++++++++++
3 files changed, 931 insertions(+)
diff --git a/package/utils/busybox/Config-defaults.in b/package/utils/busybox/Config-defaults.in
index 11cce03..1977e7f 100644
--- a/package/utils/busybox/Config-defaults.in
+++ b/package/utils/busybox/Config-defaults.in
@@ -2262,6 +2262,9 @@ config BUSYBOX_DEFAULT_FEATURE_NETSTAT_PRG
default y
config BUSYBOX_DEFAULT_NSLOOKUP
bool
+ default n
+config BUSYBOX_DEFAULT_NSLOOKUP_LEDE
+ bool
default y
config BUSYBOX_DEFAULT_NTPD
bool
diff --git a/package/utils/busybox/config/networking/Config.in b/package/utils/busybox/config/networking/Config.in
index 407ddd3..e58746b 100644
--- a/package/utils/busybox/config/networking/Config.in
+++ b/package/utils/busybox/config/networking/Config.in
@@ -850,6 +850,20 @@ config BUSYBOX_CONFIG_NSLOOKUP
help
nslookup is a tool to query Internet name servers.
+config BUSYBOX_CONFIG_NSLOOKUP_LEDE
+ bool "nslookup_lede"
+ depends on !BUSYBOX_CONFIG_NSLOOKUP
+ default BUSYBOX_DEFAULT_NSLOOKUP_LEDE
+ help
+ nslookup is a tool to query Internet name servers (LEDE flavor).
+
+config BUSYBOX_CONFIG_FEATURE_NSLOOKUP_LEDE_LONG_OPTIONS
+ bool "Enable long options"
+ default BUSYBOX_DEFAULT_FEATURE_NSLOOKUP_LEDE_LONG_OPTIONS
+ depends on BUSYBOX_CONFIG_NSLOOKUP_LEDE && BUSYBOX_CONFIG_LONG_OPTS
+ help
+ Support long options for the nslookup applet.
+
config BUSYBOX_CONFIG_NTPD
bool "ntpd"
default BUSYBOX_DEFAULT_NTPD
diff --git a/package/utils/busybox/patches/230-add_nslookup_lede.patch b/package/utils/busybox/patches/230-add_nslookup_lede.patch
new file mode 100644
index 0000000..bff88a6
--- /dev/null
+++ b/package/utils/busybox/patches/230-add_nslookup_lede.patch
@@ -0,0 +1,914 @@
+From 8c1440a0934dd8b3ad6aae48d6653b5ba6fce8a1 Mon Sep 17 00:00:00 2001
+From: Jo-Philipp Wich <jo at mein.io>
+Date: Tue, 14 Mar 2017 22:21:34 +0100
+Subject: [PATCH] networking: add LEDE nslookup applet
+
+Add a new LEDE nslookup applet which is compatible with musl libc
+and providing more features like ability to specify query type.
+
+In contrast to busybox' builtin nslookup applet, this variant does
+not rely on libc resolver internals but uses explicit send logic
+and the libresolv primitives to parse received DNS responses.
+
+Signed-off-by: Jo-Philipp Wich <jo at mein.io>
+---
+ Makefile.flags | 6 +
+ networking/nslookup_lede.c | 869 +++++++++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 875 insertions(+)
+ create mode 100644 networking/nslookup_lede.c
+
+diff --git a/Makefile.flags b/Makefile.flags
+index 65021de..096ab77 100644
+--- a/Makefile.flags
++++ b/Makefile.flags
+@@ -134,6 +134,12 @@ else
+ LDLIBS += m
+ endif
+
++# nslookup_lede might need the resolv library
++RESOLV_AVAILABLE := $(shell echo 'int main(void){res_init();return 0;}' >resolvtest.c; $(CC) $(CFLAGS) -include resolv.h -lresolv -o /dev/null resolvtest.c >/dev/null 2>&1 && echo "y"; rm resolvtest.c)
++ifeq ($(RESOLV_AVAILABLE),y)
++LDLIBS += resolv
++endif
++
+ # libpam may use libpthread, libdl and/or libaudit.
+ # On some platforms that requires an explicit -lpthread, -ldl, -laudit.
+ # However, on *other platforms* it fails when some of those flags
+diff --git a/networking/nslookup_lede.c b/networking/nslookup_lede.c
+new file mode 100644
+index 0000000..fe927ad
+--- /dev/null
++++ b/networking/nslookup_lede.c
+@@ -0,0 +1,869 @@
++/*
++ * nslookup_lede - musl compatible replacement for busybox nslookup
++ *
++ * Copyright (C) 2017 Jo-Philipp Wich <jo at mein.io>
++ *
++ * 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
++ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
++ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
++ */
++
++//config:config NSLOOKUP_LEDE
++//config: bool "nslookup_lede"
++//config: depends on !NSLOOKUP
++//config: default y
++//config: help
++//config: nslookup is a tool to query Internet name servers (LEDE flavor).
++//config:
++//config:config FEATURE_NSLOOKUP_LEDE_LONG_OPTIONS
++//config: bool "Enable long options"
++//config: default y
++//config: depends on NSLOOKUP_LEDE && LONG_OPTS
++//config: help
++//config: Support long options for the nslookup applet.
++
++//applet:IF_NSLOOKUP_LEDE(APPLET(nslookup, BB_DIR_USR_BIN, BB_SUID_DROP))
++
++//kbuild:lib-$(CONFIG_NSLOOKUP_LEDE) += nslookup_lede.o
++
++//usage:#define nslookup_lede_trivial_usage
++//usage: "[HOST] [SERVER]"
++//usage:#define nslookup_lede_full_usage "\n\n"
++//usage: "Query the nameserver for the IP address of the given HOST\n"
++//usage: "optionally using a specified DNS server"
++//usage:
++//usage:#define nslookup_lede_example_usage
++//usage: "$ nslookup localhost\n"
++//usage: "Server: default\n"
++//usage: "Address: default\n"
++//usage: "\n"
++//usage: "Name: debian\n"
++//usage: "Address: 127.0.0.1\n"
++
++#include <stdio.h>
++#include <resolv.h>
++#include <string.h>
++#include <errno.h>
++#include <time.h>
++#include <poll.h>
++#include <unistd.h>
++#include <stdlib.h>
++#include <sys/socket.h>
++#include <arpa/inet.h>
++#include <net/if.h>
++#include <netdb.h>
++
++#include "libbb.h"
++
++struct ns {
++ const char *name;
++ len_and_sockaddr addr;
++ int failures;
++ int replies;
++};
++
++struct query {
++ const char *name;
++ size_t qlen, rlen;
++ unsigned char query[512], reply[512];
++ unsigned long latency;
++ int rcode, n_ns;
++};
++
++static struct {
++ int type;
++ const char *name;
++} qtypes[] = {
++ { ns_t_soa, "SOA" },
++ { ns_t_ns, "NS" },
++ { ns_t_a, "A" },
++ { ns_t_aaaa, "AAAA" },
++ { ns_t_cname, "CNAME" },
++ { ns_t_mx, "MX" },
++ { ns_t_txt, "TXT" },
++ { ns_t_ptr, "PTR" },
++ { ns_t_any, "ANY" },
++ { }
++};
++
++static const char *rcodes[] = {
++ "NOERROR",
++ "FORMERR",
++ "SERVFAIL",
++ "NXDOMAIN",
++ "NOTIMP",
++ "REFUSED",
++ "YXDOMAIN",
++ "YXRRSET",
++ "NXRRSET",
++ "NOTAUTH",
++ "NOTZONE",
++ "RESERVED11",
++ "RESERVED12",
++ "RESERVED13",
++ "RESERVED14",
++ "RESERVED15",
++ "BADVERS"
++};
++
++static unsigned int default_port = 53;
++static unsigned int default_retry = 2;
++static unsigned int default_timeout = 5;
++
++
++static int parse_reply(const unsigned char *msg, size_t len)
++{
++ ns_msg handle;
++ ns_rr rr;
++ int i, n, rdlen;
++ const char *format = NULL;
++ char astr[INET6_ADDRSTRLEN], dname[MAXDNAME];
++ const unsigned char *cp;
++
++ if (ns_initparse(msg, len, &handle) != 0) {
++ //fprintf(stderr, "Unable to parse reply: %s\n", strerror(errno));
++ return -1;
++ }
++
++ for (i = 0; i < ns_msg_count(handle, ns_s_an); i++) {
++ if (ns_parserr(&handle, ns_s_an, i, &rr) != 0) {
++ //fprintf(stderr, "Unable to parse resource record: %s\n", strerror(errno));
++ return -1;
++ }
++
++ rdlen = ns_rr_rdlen(rr);
++
++ switch (ns_rr_type(rr))
++ {
++ case ns_t_a:
++ if (rdlen != 4) {
++ //fprintf(stderr, "Unexpected A record length\n");
++ return -1;
++ }
++ inet_ntop(AF_INET, ns_rr_rdata(rr), astr, sizeof(astr));
++ printf("Name:\t%s\nAddress: %s\n", ns_rr_name(rr), astr);
++ break;
++
++ case ns_t_aaaa:
++ if (rdlen != 16) {
++ //fprintf(stderr, "Unexpected AAAA record length\n");
++ return -1;
++ }
++ inet_ntop(AF_INET6, ns_rr_rdata(rr), astr, sizeof(astr));
++ printf("%s\thas AAAA address %s\n", ns_rr_name(rr), astr);
++ break;
++
++ case ns_t_ns:
++ if (!format)
++ format = "%s\tnameserver = %s\n";
++ /* fall through */
++
++ case ns_t_cname:
++ if (!format)
++ format = "%s\tcanonical name = %s\n";
++ /* fall through */
++
++ case ns_t_ptr:
++ if (!format)
++ format = "%s\tname = %s\n";
++ if (ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
++ ns_rr_rdata(rr), dname, sizeof(dname)) < 0) {
++ //fprintf(stderr, "Unable to uncompress domain: %s\n", strerror(errno));
++ return -1;
++ }
++ printf(format, ns_rr_name(rr), dname);
++ break;
++
++ case ns_t_mx:
++ if (rdlen < 2) {
++ fprintf(stderr, "MX record too short\n");
++ return -1;
++ }
++ n = ns_get16(ns_rr_rdata(rr));
++ if (ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
++ ns_rr_rdata(rr) + 2, dname, sizeof(dname)) < 0) {
++ //fprintf(stderr, "Cannot uncompress MX domain: %s\n", strerror(errno));
++ return -1;
++ }
++ printf("%s\tmail exchanger = %d %s\n", ns_rr_name(rr), n, dname);
++ break;
++
++ case ns_t_txt:
++ if (rdlen < 1) {
++ //fprintf(stderr, "TXT record too short\n");
++ return -1;
++ }
++ n = *(unsigned char *)ns_rr_rdata(rr);
++ if (n > 0) {
++ memset(dname, 0, sizeof(dname));
++ memcpy(dname, ns_rr_rdata(rr) + 1, n);
++ printf("%s\ttext = \"%s\"\n", ns_rr_name(rr), dname);
++ }
++ break;
++
++ case ns_t_soa:
++ if (rdlen < 20) {
++ //fprintf(stderr, "SOA record too short\n");
++ return -1;
++ }
++
++ printf("%s\n", ns_rr_name(rr));
++
++ cp = ns_rr_rdata(rr);
++ n = ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
++ cp, dname, sizeof(dname));
++
++ if (n < 0) {
++ //fprintf(stderr, "Unable to uncompress domain: %s\n", strerror(errno));
++ return -1;
++ }
++
++ printf("\torigin = %s\n", dname);
++ cp += n;
++
++ n = ns_name_uncompress(ns_msg_base(handle), ns_msg_end(handle),
++ cp, dname, sizeof(dname));
++
++ if (n < 0) {
++ //fprintf(stderr, "Unable to uncompress domain: %s\n", strerror(errno));
++ return -1;
++ }
++
++ printf("\tmail addr = %s\n", dname);
++ cp += n;
++
++ printf("\tserial = %lu\n", ns_get32(cp));
++ cp += 4;
++
++ printf("\trefresh = %lu\n", ns_get32(cp));
++ cp += 4;
++
++ printf("\tretry = %lu\n", ns_get32(cp));
++ cp += 4;
++
++ printf("\texpire = %lu\n", ns_get32(cp));
++ cp += 4;
++
++ printf("\tminimum = %lu\n", ns_get32(cp));
++ break;
++
++ default:
++ break;
++ }
++ }
++
++ return i;
++}
++
++static int parse_nsaddr(const char *addrstr, len_and_sockaddr *lsa)
++{
++ char *eptr, *hash, ifname[IFNAMSIZ];
++ unsigned int port = default_port;
++ unsigned int scope = 0;
++
++ hash = strchr(addrstr, '#');
++
++ if (hash) {
++ *hash++ = '\0';
++ port = strtoul(hash, &eptr, 10);
++
++ if (eptr == hash || *eptr != '\0' || port > 65535) {
++ errno = EINVAL;
++ return -1;
++ }
++ }
++
++ hash = strchr(addrstr, '%');
++
++ if (hash) {
++ for (eptr = ++hash; *eptr != '\0' && *eptr != '#'; eptr++) {
++ if ((eptr - hash) >= IFNAMSIZ) {
++ errno = ENODEV;
++ return -1;
++ }
++
++ ifname[eptr - hash] = *eptr;
++ }
++
++ ifname[eptr - hash] = '\0';
++ scope = if_nametoindex(ifname);
++
++ if (scope == 0) {
++ errno = ENODEV;
++ return -1;
++ }
++ }
++
++ if (inet_pton(AF_INET6, addrstr, &lsa->u.sin6.sin6_addr)) {
++ lsa->u.sin6.sin6_family = AF_INET6;
++ lsa->u.sin6.sin6_port = htons(port);
++ lsa->u.sin6.sin6_scope_id = scope;
++ lsa->len = sizeof(lsa->u.sin6);
++ return 0;
++ }
++
++ if (!scope && inet_pton(AF_INET, addrstr, &lsa->u.sin.sin_addr)) {
++ lsa->u.sin.sin_family = AF_INET;
++ lsa->u.sin.sin_port = htons(port);
++ lsa->len = sizeof(lsa->u.sin);
++ return 0;
++ }
++
++ errno = EINVAL;
++ return -1;
++}
++
++static char *make_ptr(const char *addrstr)
++{
++ const char *hexdigit = "0123456789abcdef";
++ static char ptrstr[73];
++ unsigned char addr[16];
++ char *ptr = ptrstr;
++ int i;
++
++ if (inet_pton(AF_INET6, addrstr, addr)) {
++ if (memcmp(addr, "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12) != 0) {
++ for (i = 0; i < 16; i++) {
++ *ptr++ = hexdigit[(unsigned char)addr[15 - i] & 0xf];
++ *ptr++ = '.';
++ *ptr++ = hexdigit[(unsigned char)addr[15 - i] >> 4];
++ *ptr++ = '.';
++ }
++ strcpy(ptr, "ip6.arpa");
++ }
++ else {
++ sprintf(ptr, "%u.%u.%u.%u.in-addr.arpa",
++ addr[15], addr[14], addr[13], addr[12]);
++ }
++
++ return ptrstr;
++ }
++
++ if (inet_pton(AF_INET, addrstr, addr)) {
++ sprintf(ptr, "%u.%u.%u.%u.in-addr.arpa",
++ addr[3], addr[2], addr[1], addr[0]);
++ return ptrstr;
++ }
++
++ return NULL;
++}
++
++static unsigned long mtime(void)
++{
++ struct timespec ts;
++ clock_gettime(CLOCK_REALTIME, &ts);
++ return (unsigned long)ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
++}
++
++static void to_v4_mapped(len_and_sockaddr *a)
++{
++ if (a->u.sa.sa_family != AF_INET)
++ return;
++
++ memcpy(a->u.sin6.sin6_addr.s6_addr + 12,
++ &a->u.sin.sin_addr, 4);
++
++ memcpy(a->u.sin6.sin6_addr.s6_addr,
++ "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
++
++ a->u.sin6.sin6_family = AF_INET6;
++ a->u.sin6.sin6_flowinfo = 0;
++ a->u.sin6.sin6_scope_id = 0;
++ a->len = sizeof(a->u.sin6);
++}
++
++
++/*
++ * Function logic borrowed & modified from musl libc, res_msend.c
++ */
++
++static int send_queries(struct ns *ns, int n_ns, struct query *queries, int n_queries)
++{
++ int fd;
++ int timeout = default_timeout * 1000, retry_interval, servfail_retry = 0;
++ len_and_sockaddr from = { };
++ int one = 1;
++ int recvlen = 0;
++ int n_replies = 0;
++ struct pollfd pfd;
++ unsigned long t0, t1, t2;
++ int nn, qn, next_query = 0;
++
++ from.u.sa.sa_family = AF_INET;
++ from.len = sizeof(from.u.sin);
++
++ for (nn = 0; nn < n_ns; nn++) {
++ if (ns[nn].addr.u.sa.sa_family == AF_INET6) {
++ from.u.sa.sa_family = AF_INET6;
++ from.len = sizeof(from.u.sin6);
++ break;
++ }
++ }
++
++ /* Get local address and open/bind a socket */
++ fd = socket(from.u.sa.sa_family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
++
++ /* Handle case where system lacks IPv6 support */
++ if (fd < 0 && from.u.sa.sa_family == AF_INET6 && errno == EAFNOSUPPORT) {
++ fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
++ from.u.sa.sa_family = AF_INET;
++ }
++
++ if (fd < 0)
++ return -1;
++
++ if (bind(fd, &from.u.sa, from.len) < 0) {
++ close(fd);
++ return -1;
++ }
++
++ /* Convert any IPv4 addresses in a mixed environment to v4-mapped */
++ if (from.u.sa.sa_family == AF_INET6) {
++ setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
++
++ for (nn = 0; nn < n_ns; nn++)
++ to_v4_mapped(&ns[nn].addr);
++ }
++
++ pfd.fd = fd;
++ pfd.events = POLLIN;
++ retry_interval = timeout / default_retry;
++ t0 = t2 = mtime();
++ t1 = t2 - retry_interval;
++
++ for (; t2 - t0 < timeout; t2 = mtime()) {
++ 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))
++ break;
++
++ if (qn >= n_queries || queries[qn].rlen)
++ continue;
++
++ queries[qn].rcode = queries[next_query].reply[3] & 15;
++ queries[qn].latency = mtime() - 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;
++}
++
++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
++ };
++
++ 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) : 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;
++
++ 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 = realloc(*ns, sizeof(**ns) * (*n_ns + 1));
++
++ if (!tmp)
++ return NULL;
++
++ *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;
++ char line[128], *p;
++ FILE *resolv;
++
++ if ((resolv = fopen("/etc/resolv.conf", "r")) != NULL) {
++ while (fgets(line, sizeof(line), resolv)) {
++ p = strtok(line, " \t\n");
++
++ if (!p || strcmp(p, "nameserver"))
++ continue;
++
++ p = strtok(NULL, " \t\n");
++
++ if (!p)
++ continue;
++
++ if (!add_ns(ns, n_ns, strdup(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 *tmp;
++ ssize_t qlen;
++
++ tmp = realloc(*queries, sizeof(**queries) * (*n_queries + 1));
++
++ if (!tmp)
++ return NULL;
++
++ memset(&tmp[*n_queries], 0, sizeof(*tmp));
++
++ qlen = res_mkquery(QUERY, dname, C_IN, type, NULL, 0, NULL,
++ tmp[*n_queries].query, sizeof(tmp[*n_queries].query));
++
++ tmp[*n_queries].qlen = qlen;
++ tmp[*n_queries].name = dname;
++ *queries = tmp;
++
++ return &tmp[(*n_queries)++];
++}
++
++static char *sal2str(len_and_sockaddr *a)
++{
++ static char buf[INET6_ADDRSTRLEN + 1 + IFNAMSIZ + 1 + 5 + 1];
++ char *p = buf;
++
++ if (a->u.sa.sa_family == AF_INET6) {
++ inet_ntop(AF_INET6, &a->u.sin6.sin6_addr, buf, sizeof(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 {
++ inet_ntop(AF_INET, &a->u.sin.sin_addr, buf, sizeof(buf));
++ p += strlen(p);
++ }
++
++ sprintf(p, "#%hu", ntohs(a->u.sin6.sin6_port));
++
++ return buf;
++}
++
++
++#if ENABLE_FEATURE_NSLOOKUP_LEDE_LONG_OPTIONS
++static const char nslookup_longopts[] ALIGN1 =
++ "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" Required_argument "s"
++ ;
++#endif
++
++int nslookup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
++int nslookup_main(int argc, char **argv)
++{
++ int rc = 1;
++ char *ptr, *chr;
++ struct ns *ns = NULL;
++ struct query *queries = NULL;
++ llist_t *type_strings = NULL;
++ int n_ns = 0, n_queries = 0;
++ int c, opts, option_index = 0;
++ int stats = 0;
++ unsigned int types = 0;
++ HEADER *header;
++
++#if ENABLE_FEATURE_NSLOOKUP_LEDE_LONG_OPTIONS
++ applet_long_options = nslookup_longopts;
++#endif
++
++ opts = getopt32(argv, "+q:*p:+r:+t:+s",
++ &type_strings, &default_port,
++ &default_retry, &default_timeout);
++
++ while (type_strings) {
++ ptr = llist_pop(&type_strings);
++
++ /* skip leading text, e.g. when invoked with -querytype=AAAA */
++ if ((chr = strchr(ptr, '=')) != NULL) {
++ ptr = chr;
++ *ptr++ = 0;
++ }
++
++ for (c = 0; qtypes[c].name; c++)
++ if (!strcmp(qtypes[c].name, ptr))
++ break;
++
++ if (!qtypes[c].name) {
++ fprintf(stderr, "Invalid query type \"%s\"\n", ptr);
++ goto out;
++ }
++
++ types |= (1 << c);
++ }
++
++ if (default_port > 65535) {
++ fprintf(stderr, "Invalid server port\n");
++ goto out;
++ }
++
++ if (!default_retry) {
++ fprintf(stderr, "Invalid retry value\n");
++ goto out;
++ }
++
++ if (!default_timeout) {
++ fprintf(stderr, "Invalid timeout value\n");
++ goto out;
++ }
++
++ stats = (opts & 16);
++
++ if (optind >= argc)
++ bb_show_usage();
++
++ for (option_index = optind;
++ option_index < ((argc - optind) > 1 ? argc - 1 : argc);
++ option_index++) {
++
++ /* 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 queries. */
++ if (types == 0) {
++ ptr = make_ptr(argv[option_index]);
++
++ if (ptr)
++ add_query(&queries, &n_queries, T_PTR, ptr);
++ else
++ add_query(&queries, &n_queries, T_A, argv[option_index]);
++ }
++ else {
++ for (c = 0; qtypes[c].name; c++)
++ if (types & (1 << c))
++ add_query(&queries, &n_queries, qtypes[c].type,
++ argv[option_index]);
++ }
++ }
++
++ /* Use given DNS server if present */
++ if (option_index < argc) {
++ if (!add_ns(&ns, &n_ns, argv[option_index])) {
++ fprintf(stderr, "Invalid NS server address \"%s\": %s\n",
++ argv[option_index], strerror(errno));
++ goto out;
++ }
++ }
++ 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 (c = 0; c < n_ns; c++) {
++ rc = send_queries(&ns[c], 1, queries, n_queries);
++
++ if (rc < 0) {
++ fprintf(stderr, "Failed to send queries: %s\n", strerror(errno));
++ goto out;
++ } else if (rc > 0) {
++ break;
++ }
++ }
++
++ if (c >= n_ns) {
++ fprintf(stderr,
++ ";; connection timed out; no servers could be reached\n\n");
++
++ return 1;
++ }
++
++ printf("Server:\t\t%s\n", ns[c].name);
++ printf("Address:\t%s\n", sal2str(&ns[c].addr));
++
++ if (stats) {
++ printf("Replies:\t%d\n", ns[c].replies);
++ printf("Failures:\t%d\n", ns[c].failures);
++ }
++
++ printf("\n");
++
++ for (rc = 0; rc < n_queries; rc++) {
++ if (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 *)queries[rc].reply;
++
++ if (!header->aa)
++ printf("Non-authoritative answer:\n");
++
++ c = parse_reply(queries[rc].reply, queries[rc].rlen);
++ }
++
++ 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);
++
++ printf("\n");
++ }
++
++ rc = 0;
++
++out:
++ if (n_ns)
++ free(ns);
++
++ if (n_queries)
++ free(queries);
++
++ return rc;
++}
+--
+2.1.4
+
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