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nsd.c
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nsd.c
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/*
* nsd.c -- nsd(8)
*
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
*
* See LICENSE for the license.
*
*/
#include "config.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#ifdef HAVE_GRP_H
#include <grp.h>
#endif /* HAVE_GRP_H */
#ifdef HAVE_SETUSERCONTEXT
#ifdef HAVE_LOGIN_CAP_H
#include <login_cap.h>
#endif /* HAVE_LOGIN_CAP_H */
#endif /* HAVE_SETUSERCONTEXT */
#ifdef HAVE_OPENSSL_RAND_H
#include <openssl/rand.h>
#endif
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#ifdef HAVE_IFADDRS_H
#include <ifaddrs.h>
#endif
#include "nsd.h"
#include "options.h"
#include "tsig.h"
#include "remote.h"
#include "xfrd-disk.h"
#include "ipc.h"
#ifdef USE_DNSTAP
#include "dnstap/dnstap_collector.h"
#endif
#include "util/proxy_protocol.h"
/* The server handler... */
struct nsd nsd;
static char hostname[MAXHOSTNAMELEN];
extern config_parser_state_type* cfg_parser;
static void version(void) ATTR_NORETURN;
/*
* Print the help text.
*
*/
static void
usage (void)
{
fprintf(stderr, "Usage: nsd [OPTION]...\n");
fprintf(stderr, "Name Server Daemon.\n\n");
fprintf(stderr,
"Supported options:\n"
" -4 Only listen to IPv4 connections.\n"
" -6 Only listen to IPv6 connections.\n"
" -a ip-address[@port] Listen to the specified incoming IP address (and port)\n"
" May be specified multiple times).\n"
" -c configfile Read specified configfile instead of %s.\n"
" -d do not fork as a daemon process.\n"
#ifndef NDEBUG
" -F facilities Specify the debug facilities.\n"
#endif /* NDEBUG */
" -h Print this help information.\n"
, CONFIGFILE);
fprintf(stderr,
" -i identity Specify the identity when queried for id.server CHAOS TXT.\n"
" -I nsid Specify the NSID. This must be a hex string.\n"
#ifndef NDEBUG
" -L level Specify the debug level.\n"
#endif /* NDEBUG */
" -l filename Specify the log file.\n"
" -N server-count The number of servers to start.\n"
" -n tcp-count The maximum number of TCP connections per server.\n"
" -P pidfile Specify the PID file to write.\n"
" -p port Specify the port to listen to.\n"
" -s seconds Dump statistics every SECONDS seconds.\n"
" -t chrootdir Change root to specified directory on startup.\n"
);
fprintf(stderr,
" -u user Change effective uid to the specified user.\n"
" -V level Specify verbosity level.\n"
" -v Print version information.\n"
);
fprintf(stderr, "Version %s. Report bugs to <%s>.\n",
PACKAGE_VERSION, PACKAGE_BUGREPORT);
}
/*
* Print the version exit.
*
*/
static void
version(void)
{
fprintf(stderr, "%s version %s\n", PACKAGE_NAME, PACKAGE_VERSION);
fprintf(stderr, "Written by NLnet Labs.\n\n");
fprintf(stderr, "Configure line: %s\n", CONFCMDLINE);
#ifdef USE_MINI_EVENT
fprintf(stderr, "Event loop: internal (uses select)\n");
#else
# if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
fprintf(stderr, "Event loop: %s %s (uses %s)\n",
"libev",
nsd_event_vs(),
nsd_event_method());
# else
fprintf(stderr, "Event loop: %s %s (uses %s)\n",
"libevent",
nsd_event_vs(),
nsd_event_method());
# endif
#endif
#ifdef HAVE_SSL
fprintf(stderr, "Linked with %s\n\n",
# ifdef SSLEAY_VERSION
SSLeay_version(SSLEAY_VERSION)
# else
OpenSSL_version(OPENSSL_VERSION)
# endif
);
#endif
fprintf(stderr,
"Copyright (C) 2001-2020 NLnet Labs. This is free software.\n"
"There is NO warranty; not even for MERCHANTABILITY or FITNESS\n"
"FOR A PARTICULAR PURPOSE.\n");
exit(0);
}
static void
setup_verifier_environment(void)
{
size_t i;
int ret, ip4, ip6;
char *buf, host[NI_MAXHOST], serv[NI_MAXSERV];
size_t size, cnt = 0;
/* allocate large enough buffer to hold a list of all ip addresses.
((" " + INET6_ADDRSTRLEN + "@" + "65535") * n) + "\0" */
size = ((INET6_ADDRSTRLEN + 1 + 5 + 1) * nsd.verify_ifs) + 1;
buf = xalloc(size);
ip4 = ip6 = 0;
for(i = 0; i < nsd.verify_ifs; i++) {
ret = getnameinfo(
(struct sockaddr *)&nsd.verify_udp[i].addr.ai_addr,
nsd.verify_udp[i].addr.ai_addrlen,
host, sizeof(host), serv, sizeof(serv),
NI_NUMERICHOST | NI_NUMERICSERV);
if(ret != 0) {
log_msg(LOG_ERR, "error in getnameinfo: %s",
gai_strerror(ret));
continue;
}
buf[cnt++] = ' ';
cnt += strlcpy(&buf[cnt], host, size - cnt);
assert(cnt < size);
buf[cnt++] = '@';
cnt += strlcpy(&buf[cnt], serv, size - cnt);
assert(cnt < size);
#ifdef INET6
if (nsd.verify_udp[i].addr.ai_family == AF_INET6 && !ip6) {
setenv("VERIFY_IPV6_ADDRESS", host, 1);
setenv("VERIFY_IPV6_PORT", serv, 1);
setenv("VERIFY_IP_ADDRESS", host, 1);
setenv("VERIFY_PORT", serv, 1);
ip6 = 1;
} else
#endif
if (!ip4) {
assert(nsd.verify_udp[i].addr.ai_family == AF_INET);
setenv("VERIFY_IPV4_ADDRESS", host, 1);
setenv("VERIFY_IPV4_PORT", serv, 1);
if (!ip6) {
setenv("VERIFY_IP_ADDRESS", host, 1);
setenv("VERIFY_PORT", serv, 1);
}
ip4 = 1;
}
}
setenv("VERIFY_IP_ADDRESSES", &buf[1], 1);
free(buf);
}
static void
copyaddrinfo(struct nsd_addrinfo *dest, struct addrinfo *src)
{
dest->ai_flags = src->ai_flags;
dest->ai_family = src->ai_family;
dest->ai_socktype = src->ai_socktype;
dest->ai_addrlen = src->ai_addrlen;
memcpy(&dest->ai_addr, src->ai_addr, src->ai_addrlen);
}
static void
setup_socket(
struct nsd_socket *sock, const char *node, const char *port,
struct addrinfo *hints)
{
int ret;
char *host;
char host_buf[sizeof("65535") + INET6_ADDRSTRLEN + 1 /* '\0' */];
const char *service;
struct addrinfo *addr = NULL;
sock->fib = -1;
if(node) {
char *sep;
if (strlcpy(host_buf, node, sizeof(host_buf)) >= sizeof(host_buf)) {
error("cannot parse address '%s': %s", node,
strerror(ENAMETOOLONG));
}
host = host_buf;
sep = strchr(host_buf, '@');
if(sep != NULL) {
*sep = '\0';
service = sep + 1;
} else {
service = port;
}
} else {
host = NULL;
service = port;
}
if((ret = getaddrinfo(host, service, hints, &addr)) == 0) {
copyaddrinfo(&sock->addr, addr);
freeaddrinfo(addr);
} else {
error("cannot parse address '%s': getaddrinfo: %s %s",
host ? host : "(null)",
gai_strerror(ret),
ret==EAI_SYSTEM ? strerror(errno) : "");
}
}
static void
figure_socket_servers(
struct nsd_socket *sock, struct ip_address_option *ip)
{
int i;
struct range_option *server;
sock->servers = xalloc_zero(nsd_bitset_size(nsd.child_count));
region_add_cleanup(nsd.region, free, sock->servers);
nsd_bitset_init(sock->servers, nsd.child_count);
if(!ip || !ip->servers) {
/* every server must listen on this socket */
for(i = 0; i < (int)nsd.child_count; i++) {
nsd_bitset_set(sock->servers, i);
}
return;
}
/* only specific servers must listen on this socket */
for(server = ip->servers; server; server = server->next) {
if(server->first == server->last) {
if(server->first <= 0) {
error("server %d specified for ip-address %s "
"is invalid; server ranges are 1-based",
server->first, ip->address);
} else if(server->last > (int)nsd.child_count) {
error("server %d specified for ip-address %s "
"exceeds number of servers configured "
"in server-count",
server->first, ip->address);
}
} else {
/* parse_range must ensure range itself is valid */
assert(server->first < server->last);
if(server->first <= 0) {
error("server range %d-%d specified for "
"ip-address %s is invalid; server "
"ranges are 1-based",
server->first, server->last, ip->address);
} else if(server->last > (int)nsd.child_count) {
error("server range %d-%d specified for "
"ip-address %s exceeds number of servers "
"configured in server-count",
server->first, server->last, ip->address);
}
}
for(i = server->first - 1; i < server->last; i++) {
nsd_bitset_set(sock->servers, i);
}
}
}
static void
figure_default_sockets(
struct nsd_socket **udp, struct nsd_socket **tcp, size_t *ifs,
const char *node, const char *udp_port, const char *tcp_port,
const struct addrinfo *hints)
{
size_t i = 0, n = 1;
struct addrinfo ai[2] = { *hints, *hints };
assert(udp != NULL);
assert(tcp != NULL);
assert(ifs != NULL);
ai[0].ai_socktype = SOCK_DGRAM;
ai[1].ai_socktype = SOCK_STREAM;
#ifdef INET6
#ifdef IPV6_V6ONLY
if (hints->ai_family == AF_UNSPEC) {
ai[0].ai_family = AF_INET6;
ai[1].ai_family = AF_INET6;
n++;
}
#endif /* IPV6_V6ONLY */
#endif /* INET6 */
*udp = xalloc_zero((n + 1) * sizeof(struct nsd_socket));
*tcp = xalloc_zero((n + 1) * sizeof(struct nsd_socket));
region_add_cleanup(nsd.region, free, *udp);
region_add_cleanup(nsd.region, free, *tcp);
#ifdef INET6
if(hints->ai_family == AF_UNSPEC) {
/*
* With IPv6 we'd like to open two separate sockets, one for
* IPv4 and one for IPv6, both listening to the wildcard
* address (unless the -4 or -6 flags are specified).
*
* However, this is only supported on platforms where we can
* turn the socket option IPV6_V6ONLY _on_. Otherwise we just
* listen to a single IPv6 socket and any incoming IPv4
* connections will be automatically mapped to our IPv6
* socket.
*/
#ifdef IPV6_V6ONLY
int r;
struct addrinfo *addrs[2] = { NULL, NULL };
if((r = getaddrinfo(node, udp_port, &ai[0], &addrs[0])) == 0 &&
(r = getaddrinfo(node, tcp_port, &ai[1], &addrs[1])) == 0)
{
(*udp)[i].flags |= NSD_SOCKET_IS_OPTIONAL;
(*udp)[i].fib = -1;
copyaddrinfo(&(*udp)[i].addr, addrs[0]);
figure_socket_servers(&(*udp)[i], NULL);
(*tcp)[i].flags |= NSD_SOCKET_IS_OPTIONAL;
(*tcp)[i].fib = -1;
copyaddrinfo(&(*tcp)[i].addr, addrs[1]);
figure_socket_servers(&(*tcp)[i], NULL);
i++;
} else {
log_msg(LOG_WARNING, "No IPv6, fallback to IPv4. getaddrinfo: %s",
r == EAI_SYSTEM ? strerror(errno) : gai_strerror(r));
}
if(addrs[0])
freeaddrinfo(addrs[0]);
if(addrs[1])
freeaddrinfo(addrs[1]);
ai[0].ai_family = AF_INET;
ai[1].ai_family = AF_INET;
#endif /* IPV6_V6ONLY */
}
#endif /* INET6 */
*ifs = i + 1;
setup_socket(&(*udp)[i], node, udp_port, &ai[0]);
figure_socket_servers(&(*udp)[i], NULL);
setup_socket(&(*tcp)[i], node, tcp_port, &ai[1]);
figure_socket_servers(&(*tcp)[i], NULL);
}
#ifdef HAVE_GETIFADDRS
static int
find_device(
struct nsd_socket *sock,
const struct ifaddrs *ifa)
{
for(; ifa != NULL; ifa = ifa->ifa_next) {
if((ifa->ifa_addr == NULL) ||
(ifa->ifa_addr->sa_family != sock->addr.ai_family) ||
((ifa->ifa_flags & IFF_UP) == 0 ||
(ifa->ifa_flags & IFF_LOOPBACK) != 0 ||
(ifa->ifa_flags & IFF_RUNNING) == 0))
{
continue;
}
#ifdef INET6
if(ifa->ifa_addr->sa_family == AF_INET6) {
struct sockaddr_in6 *sa1, *sa2;
size_t sz = sizeof(struct in6_addr);
sa1 = (struct sockaddr_in6 *)ifa->ifa_addr;
sa2 = (struct sockaddr_in6 *)&sock->addr.ai_addr;
if(memcmp(&sa1->sin6_addr, &sa2->sin6_addr, sz) == 0) {
break;
}
} else
#endif
if(ifa->ifa_addr->sa_family == AF_INET) {
struct sockaddr_in *sa1, *sa2;
sa1 = (struct sockaddr_in *)ifa->ifa_addr;
sa2 = (struct sockaddr_in *)&sock->addr.ai_addr;
if(sa1->sin_addr.s_addr == sa2->sin_addr.s_addr) {
break;
}
}
}
if(ifa != NULL) {
size_t len = strlcpy(sock->device, ifa->ifa_name, sizeof(sock->device));
if(len < sizeof(sock->device)) {
char *colon = strchr(sock->device, ':');
if(colon != NULL)
*colon = '\0';
return 1;
}
}
return 0;
}
#endif /* HAVE_GETIFADDRS */
static void
figure_sockets(
struct nsd_socket **udp, struct nsd_socket **tcp, size_t *ifs,
struct ip_address_option *ips,
const char *node, const char *udp_port, const char *tcp_port,
const struct addrinfo *hints)
{
size_t i = 0;
struct addrinfo ai = *hints;
struct ip_address_option *ip;
#ifdef HAVE_GETIFADDRS
struct ifaddrs *ifa = NULL;
#endif
int bind_device = 0;
if(!ips) {
figure_default_sockets(
udp, tcp, ifs, node, udp_port, tcp_port, hints);
return;
}
*ifs = 0;
for(ip = ips; ip; ip = ip->next) {
(*ifs)++;
bind_device |= (ip->dev != 0);
}
#ifdef HAVE_GETIFADDRS
if(bind_device && getifaddrs(&ifa) == -1) {
error("getifaddrs failed: %s", strerror(errno));
}
#endif
*udp = xalloc_zero((*ifs + 1) * sizeof(struct nsd_socket));
*tcp = xalloc_zero((*ifs + 1) * sizeof(struct nsd_socket));
region_add_cleanup(nsd.region, free, *udp);
region_add_cleanup(nsd.region, free, *tcp);
ai.ai_flags |= AI_NUMERICHOST;
for(ip = ips, i = 0; ip; ip = ip->next, i++) {
ai.ai_socktype = SOCK_DGRAM;
setup_socket(&(*udp)[i], ip->address, udp_port, &ai);
figure_socket_servers(&(*udp)[i], ip);
ai.ai_socktype = SOCK_STREAM;
setup_socket(&(*tcp)[i], ip->address, tcp_port, &ai);
figure_socket_servers(&(*tcp)[i], ip);
if(ip->fib != -1) {
(*udp)[i].fib = ip->fib;
(*tcp)[i].fib = ip->fib;
}
#ifdef HAVE_GETIFADDRS
if(ip->dev != 0) {
(*udp)[i].flags |= NSD_BIND_DEVICE;
(*tcp)[i].flags |= NSD_BIND_DEVICE;
if(ifa != NULL && (find_device(&(*udp)[i], ifa) == 0 ||
find_device(&(*tcp)[i], ifa) == 0))
{
error("cannot find device for ip-address %s",
ip->address);
}
}
#endif
}
assert(i == *ifs);
#ifdef HAVE_GETIFADDRS
if(ifa != NULL) {
freeifaddrs(ifa);
}
#endif
}
/* print server affinity for given socket. "*" if socket has no affinity with
any specific server, "x-y" if socket has affinity with more than two
consecutively numbered servers, "x" if socket has affinity with a specific
server number, which is not necessarily just one server. e.g. "1 3" is
printed if socket has affinity with servers number one and three, but not
server number two. */
static ssize_t
print_socket_servers(struct nsd_socket *sock, char *buf, size_t bufsz)
{
int i, x, y, z, n = (int)(sock->servers->size);
char *sep = "";
size_t off, tot;
ssize_t cnt = 0;
assert(bufsz != 0);
off = tot = 0;
x = y = z = -1;
for (i = 0; i <= n; i++) {
if (i == n || !nsd_bitset_isset(sock->servers, i)) {
cnt = 0;
if (i == n && x == -1) {
assert(y == -1);
assert(z == -1);
cnt = snprintf(buf, bufsz, "-");
} else if (y > z) {
assert(x > z);
if (x == 0 && y == (n - 1)) {
assert(z == -1);
cnt = snprintf(buf+off, bufsz-off,
"*");
} else if (x == y) {
cnt = snprintf(buf+off, bufsz-off,
"%s%d", sep, x+1);
} else if (x == (y - 1)) {
cnt = snprintf(buf+off, bufsz-off,
"%s%d %d", sep, x+1, y+1);
} else {
assert(y > (x + 1));
cnt = snprintf(buf+off, bufsz-off,
"%s%d-%d", sep, x+1, y+1);
}
}
z = i;
if (cnt > 0) {
tot += (size_t)cnt;
off = (tot < bufsz) ? tot : bufsz - 1;
sep = " ";
} else if (cnt < 0) {
return -1;
}
} else if (x <= z) {
x = y = i;
} else {
assert(x > z);
y = i;
}
}
return tot;
}
static void
print_sockets(
struct nsd_socket *udp, struct nsd_socket *tcp, size_t ifs)
{
char sockbuf[INET6_ADDRSTRLEN + 6 + 1];
char *serverbuf;
size_t i, serverbufsz, servercnt;
const char *fmt = "listen on ip-address %s (%s) with server(s): %s";
struct nsd_bitset *servers;
if(ifs == 0) {
return;
}
assert(udp != NULL);
assert(tcp != NULL);
servercnt = udp[0].servers->size;
serverbufsz = (((servercnt / 10) * servercnt) + servercnt) + 1;
serverbuf = xalloc(serverbufsz);
/* warn user of unused servers */
servers = xalloc(nsd_bitset_size(servercnt));
nsd_bitset_init(servers, (size_t)servercnt);
for(i = 0; i < ifs; i++) {
assert(udp[i].servers->size == servercnt);
addrport2str((void*)&udp[i].addr.ai_addr, sockbuf, sizeof(sockbuf));
print_socket_servers(&udp[i], serverbuf, serverbufsz);
nsd_bitset_or(servers, servers, udp[i].servers);
VERBOSITY(3, (LOG_NOTICE, fmt, sockbuf, "udp", serverbuf));
assert(tcp[i].servers->size == servercnt);
addrport2str((void*)&tcp[i].addr.ai_addr, sockbuf, sizeof(sockbuf));
print_socket_servers(&tcp[i], serverbuf, serverbufsz);
nsd_bitset_or(servers, servers, tcp[i].servers);
VERBOSITY(3, (LOG_NOTICE, fmt, sockbuf, "tcp", serverbuf));
}
/* warn user of unused servers */
for(i = 0; i < servercnt; i++) {
if(!nsd_bitset_isset(servers, i)) {
log_msg(LOG_WARNING, "server %zu will not listen on "
"any specified ip-address", i+1);
}
}
free(serverbuf);
free(servers);
}
#ifdef HAVE_CPUSET_T
static void free_cpuset(void *ptr)
{
cpuset_t *set = (cpuset_t *)ptr;
cpuset_destroy(set);
}
#endif
/*
* Fetch the nsd parent process id from the nsd pidfile
*
*/
pid_t
readpid(const char *file)
{
int fd;
pid_t pid;
char pidbuf[16];
char *t;
int l;
if ((fd = open(file, O_RDONLY)) == -1) {
return -1;
}
if (((l = read(fd, pidbuf, sizeof(pidbuf)))) == -1) {
close(fd);
return -1;
}
close(fd);
/* Empty pidfile means no pidfile... */
if (l == 0) {
errno = ENOENT;
return -1;
}
pid = (pid_t) strtol(pidbuf, &t, 10);
if (*t && *t != '\n') {
return -1;
}
return pid;
}
/*
* Store the nsd parent process id in the nsd pidfile
*
*/
int
writepid(struct nsd *nsd)
{
int fd;
char pidbuf[32];
size_t count = 0;
if(!nsd->pidfile || !nsd->pidfile[0])
return 0;
snprintf(pidbuf, sizeof(pidbuf), "%lu\n", (unsigned long) nsd->pid);
if((fd = open(nsd->pidfile, O_WRONLY | O_CREAT | O_TRUNC
#ifdef O_NOFOLLOW
| O_NOFOLLOW
#endif
, 0644)) == -1) {
log_msg(LOG_ERR, "cannot open pidfile %s: %s",
nsd->pidfile, strerror(errno));
return -1;
}
while(count < strlen(pidbuf)) {
ssize_t r = write(fd, pidbuf+count, strlen(pidbuf)-count);
if(r == -1) {
if(errno == EAGAIN || errno == EINTR)
continue;
log_msg(LOG_ERR, "cannot write pidfile %s: %s",
nsd->pidfile, strerror(errno));
close(fd);
return -1;
} else if(r == 0) {
log_msg(LOG_ERR, "cannot write any bytes to "
"pidfile %s: write returns 0 bytes written",
nsd->pidfile);
close(fd);
return -1;
}
count += r;
}
close(fd);
return 0;
}
void
unlinkpid(const char* file, const char* username)
{
int fd = -1;
if (file && file[0]) {
/* truncate pidfile */
fd = open(file, O_WRONLY | O_TRUNC
#ifdef O_NOFOLLOW
| O_NOFOLLOW
#endif
, 0644);
if (fd == -1) {
/* Truncate the pid file. */
/* If there is a username configured, we assume that
* due to privilege drops, NSD cannot truncate or
* unlink the pid file. NSD does not chown the file
* because that creates a privilege escape. */
if(username && username[0]) {
VERBOSITY(5, (LOG_INFO, "can not truncate the pid file %s: %s", file, strerror(errno)));
} else {
log_msg(LOG_ERR, "can not truncate the pid file %s: %s", file, strerror(errno));
}
} else {
close(fd);
}
/* unlink pidfile */
if (unlink(file) == -1) {
/* this unlink may not work if the pidfile is located
* outside of the chroot/workdir or we no longer
* have permissions */
if(username && username[0]) {
VERBOSITY(5, (LOG_INFO,
"failed to unlink pidfile %s: %s",
file, strerror(errno)));
} else {
VERBOSITY(3, (LOG_WARNING,
"failed to unlink pidfile %s: %s",
file, strerror(errno)));
}
}
}
}
/*
* Incoming signals, set appropriate actions.
*
*/
void
sig_handler(int sig)
{
/* To avoid race cond. We really don't want to use log_msg() in this handler */
/* Are we a child server? */
if (nsd.server_kind != NSD_SERVER_MAIN) {
switch (sig) {
case SIGCHLD:
nsd.signal_hint_child = 1;
break;
case SIGALRM:
break;
case SIGINT:
case SIGTERM:
nsd.signal_hint_quit = 1;
break;
case SIGILL:
case SIGUSR1: /* Dump stats on SIGUSR1. */
nsd.signal_hint_statsusr = 1;
break;
default:
break;
}
return;
}
/* We are the main process */
switch (sig) {
case SIGCHLD:
nsd.signal_hint_child = 1;
return;
case SIGHUP:
nsd.signal_hint_reload_hup = 1;
return;
case SIGALRM:
nsd.signal_hint_stats = 1;
break;
case SIGILL:
/*
* For backwards compatibility with BIND 8 and older
* versions of NSD.
*/
nsd.signal_hint_statsusr = 1;
break;
case SIGUSR1:
/* Dump statistics. */
nsd.signal_hint_statsusr = 1;
break;
case SIGINT:
case SIGTERM:
default:
nsd.signal_hint_shutdown = 1;
break;
}
}
/*
* Statistic output...
*
*/
#ifdef BIND8_STATS
void
bind8_stats (struct nsd *nsd)
{
char buf[MAXSYSLOGMSGLEN];
char *msg, *t;
int i, len;
struct nsdst st;
/* Current time... */
time_t now;
if(!nsd->st_period)
return;
time(&now);
memcpy(&st, nsd->st, sizeof(st));
stats_subtract(&st, &nsd->stat_proc);
/* NSTATS */
t = msg = buf + snprintf(buf, MAXSYSLOGMSGLEN, "NSTATS %lld %lu",
(long long) now, (unsigned long) st.boot);
for (i = 0; i <= 255; i++) {
/* How much space left? */
if ((len = buf + MAXSYSLOGMSGLEN - t) < 32) {
log_msg(LOG_INFO, "%s", buf);
t = msg;
len = buf + MAXSYSLOGMSGLEN - t;
}
if (st.qtype[i] != 0) {
t += snprintf(t, len, " %s=%lu", rrtype_to_string(i), st.qtype[i]);
}
}
if (t > msg)
log_msg(LOG_INFO, "%s", buf);
/* XSTATS */
/* Only print it if we're in the main daemon or have anything to report... */
if (nsd->server_kind == NSD_SERVER_MAIN
|| st.dropped || st.raxfr || st.rixfr || (st.qudp + st.qudp6 - st.dropped)
|| st.txerr || st.opcode[OPCODE_QUERY] || st.opcode[OPCODE_IQUERY]
|| st.wrongzone || st.ctcp + st.ctcp6 || st.rcode[RCODE_SERVFAIL]
|| st.rcode[RCODE_FORMAT] || st.nona || st.rcode[RCODE_NXDOMAIN]
|| st.opcode[OPCODE_UPDATE]) {
log_msg(LOG_INFO, "XSTATS %lld %lu"
" RR=%lu RNXD=%lu RFwdR=%lu RDupR=%lu RFail=%lu RFErr=%lu RErr=%lu RAXFR=%lu RIXFR=%lu"
" RLame=%lu ROpts=%lu SSysQ=%lu SAns=%lu SFwdQ=%lu SDupQ=%lu SErr=%lu RQ=%lu"
" RIQ=%lu RFwdQ=%lu RDupQ=%lu RTCP=%lu SFwdR=%lu SFail=%lu SFErr=%lu SNaAns=%lu"
" SNXD=%lu RUQ=%lu RURQ=%lu RUXFR=%lu RUUpd=%lu",
(long long) now, (unsigned long) st.boot,
st.dropped, (unsigned long)0, (unsigned long)0, (unsigned long)0, (unsigned long)0,
(unsigned long)0, (unsigned long)0, st.raxfr, st.rixfr, (unsigned long)0, (unsigned long)0,
(unsigned long)0, st.qudp + st.qudp6 - st.dropped, (unsigned long)0,
(unsigned long)0, st.txerr,
st.opcode[OPCODE_QUERY], st.opcode[OPCODE_IQUERY], st.wrongzone,
(unsigned long)0, st.ctcp + st.ctcp6,
(unsigned long)0, st.rcode[RCODE_SERVFAIL], st.rcode[RCODE_FORMAT],
st.nona, st.rcode[RCODE_NXDOMAIN],
(unsigned long)0, (unsigned long)0, (unsigned long)0, st.opcode[OPCODE_UPDATE]);
}
}
#endif /* BIND8_STATS */
static
int cookie_secret_file_read(nsd_type* nsd) {
char secret[NSD_COOKIE_SECRET_SIZE * 2 + 2/*'\n' and '\0'*/];
char const* file = nsd->options->cookie_secret_file;
FILE* f;
int corrupt = 0;
size_t count;
assert( nsd->options->cookie_secret_file != NULL );
f = fopen(file, "r");
/* a non-existing cookie file is not an error */
if( f == NULL ) { return errno != EPERM; }
/* cookie secret file exists and is readable */
nsd->cookie_count = 0;
for( count = 0; count < NSD_COOKIE_HISTORY_SIZE; count++ ) {
size_t secret_len = 0;
ssize_t decoded_len = 0;
if( fgets(secret, sizeof(secret), f) == NULL ) { break; }
secret_len = strlen(secret);
if( secret_len == 0 ) { break; }
assert( secret_len <= sizeof(secret) );
secret_len = secret[secret_len - 1] == '\n' ? secret_len - 1 : secret_len;
if( secret_len != NSD_COOKIE_SECRET_SIZE * 2 ) { corrupt++; break; }
/* needed for `hex_pton`; stripping potential `\n` */
secret[secret_len] = '\0';
decoded_len = hex_pton(secret, nsd->cookie_secrets[count].cookie_secret,
NSD_COOKIE_SECRET_SIZE);
if( decoded_len != NSD_COOKIE_SECRET_SIZE ) { corrupt++; break; }
nsd->cookie_count++;
}
fclose(f);
return corrupt == 0;
}
extern char *optarg;
extern int optind;
int
main(int argc, char *argv[])
{
/* Scratch variables... */
int c;
pid_t oldpid;
size_t i;
struct sigaction action;
#ifdef HAVE_GETPWNAM
struct passwd *pwd = NULL;
#endif /* HAVE_GETPWNAM */
struct ip_address_option *ip;
struct addrinfo hints;
const char *udp_port = 0;
const char *tcp_port = 0;
const char *verify_port = 0;
const char *configfile = CONFIGFILE;
char* argv0 = (argv0 = strrchr(argv[0], '/')) ? argv0 + 1 : argv[0];
log_init(argv0);
/* Initialize the server handler... */
memset(&nsd, 0, sizeof(struct nsd));
nsd.region = region_create(xalloc, free);
nsd.pidfile = 0;
nsd.server_kind = NSD_SERVER_MAIN;
memset(&hints, 0, sizeof(hints));
hints.ai_family = DEFAULT_AI_FAMILY;
hints.ai_flags = AI_PASSIVE;
nsd.identity = 0;
nsd.version = VERSION;
nsd.username = 0;
nsd.chrootdir = 0;
nsd.nsid = NULL;
nsd.nsid_len = 0;
nsd.cookie_count = 0;
nsd.child_count = 0;
nsd.maximum_tcp_count = 0;
nsd.current_tcp_count = 0;
nsd.file_rotation_ok = 0;
nsd.do_answer_cookie = 1;
/* Set up our default identity to gethostname(2) */
if (gethostname(hostname, MAXHOSTNAMELEN) == 0) {
nsd.identity = hostname;
} else {
log_msg(LOG_ERR,
"failed to get the host name: %s - using default identity",
strerror(errno));
nsd.identity = IDENTITY;
}
/* Create region where options will be stored and set defaults */
nsd.options = nsd_options_create(region_create_custom(xalloc, free,