freebsd-dev/usr.bin/whois/whois.c
Conrad Meyer 68c47fcfad whois(1): Pull out async multiple host connection code into a routine
This logic was added to the whois() function in r281959, but could easily be
its own routine.  In this case, I think the abstraction makes both functions
easier to reason about.

This precedes some Coverity-suggested cleanup.

Sponsored by:	EMC / Isilon Storage Division
2016-05-11 17:52:06 +00:00

521 lines
12 KiB
C

/*-
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#if 0
#ifndef lint
static char sccsid[] = "@(#)whois.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/poll.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <err.h>
#include <netdb.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#define ABUSEHOST "whois.abuse.net"
#define ANICHOST "whois.arin.net"
#define DENICHOST "whois.denic.de"
#define DKNICHOST "whois.dk-hostmaster.dk"
#define FNICHOST "whois.afrinic.net"
#define GNICHOST "whois.nic.gov"
#define IANAHOST "whois.iana.org"
#define INICHOST "whois.internic.net"
#define KNICHOST "whois.krnic.net"
#define LNICHOST "whois.lacnic.net"
#define MNICHOST "whois.ra.net"
#define PDBHOST "whois.peeringdb.com"
#define PNICHOST "whois.apnic.net"
#define QNICHOST_TAIL ".whois-servers.net"
#define RNICHOST "whois.ripe.net"
#define VNICHOST "whois.verisign-grs.com"
#define DEFAULT_PORT "whois"
#define WHOIS_RECURSE 0x01
#define WHOIS_QUICK 0x02
#define WHOIS_SPAM_ME 0x04
#define CHOPSPAM ">>> Last update of WHOIS database:"
#define ishost(h) (isalnum((unsigned char)h) || h == '.' || h == '-')
#define SCAN(p, end, check) \
while ((p) < (end)) \
if (check) ++(p); \
else break
static struct {
const char *suffix, *server;
} whoiswhere[] = {
/* Various handles */
{ "-ARIN", ANICHOST },
{ "-NICAT", "at" QNICHOST_TAIL },
{ "-NORID", "no" QNICHOST_TAIL },
{ "-RIPE", RNICHOST },
/* Nominet's whois server doesn't return referrals to JANET */
{ ".ac.uk", "ac.uk" QNICHOST_TAIL },
{ "", IANAHOST }, /* default */
{ NULL, NULL } /* safety belt */
};
#define WHOIS_REFERRAL(s) { s, sizeof(s) - 1 }
static struct {
const char *prefix;
size_t len;
} whois_referral[] = {
WHOIS_REFERRAL("whois:"), /* IANA */
WHOIS_REFERRAL("Whois Server:"),
WHOIS_REFERRAL("Registrar WHOIS Server:"), /* corporatedomains.com */
WHOIS_REFERRAL("ReferralServer: whois://"), /* ARIN */
WHOIS_REFERRAL("descr: region. Please query"), /* AfriNIC */
{ NULL, 0 }
};
static const char *actually_arin[] = {
"netname: ERX-NETBLOCK\n", /* APNIC */
"netname: NON-RIPE-NCC-MANAGED-ADDRESS-BLOCK\n",
NULL
};
static const char *port = DEFAULT_PORT;
static const char *choose_server(char *);
static struct addrinfo *gethostinfo(char const *host, int exitnoname);
static void s_asprintf(char **ret, const char *format, ...) __printflike(2, 3);
static void usage(void);
static void whois(const char *, const char *, int);
int
main(int argc, char *argv[])
{
const char *country, *host;
int ch, flags;
#ifdef SOCKS
SOCKSinit(argv[0]);
#endif
country = host = NULL;
flags = 0;
while ((ch = getopt(argc, argv, "aAbc:fgh:iIklmp:PQrRS")) != -1) {
switch (ch) {
case 'a':
host = ANICHOST;
break;
case 'A':
host = PNICHOST;
break;
case 'b':
host = ABUSEHOST;
break;
case 'c':
country = optarg;
break;
case 'f':
host = FNICHOST;
break;
case 'g':
host = GNICHOST;
break;
case 'h':
host = optarg;
break;
case 'i':
host = INICHOST;
break;
case 'I':
host = IANAHOST;
break;
case 'k':
host = KNICHOST;
break;
case 'l':
host = LNICHOST;
break;
case 'm':
host = MNICHOST;
break;
case 'p':
port = optarg;
break;
case 'P':
host = PDBHOST;
break;
case 'Q':
flags |= WHOIS_QUICK;
break;
case 'r':
host = RNICHOST;
break;
case 'R':
flags |= WHOIS_RECURSE;
break;
case 'S':
flags |= WHOIS_SPAM_ME;
break;
case '?':
default:
usage();
/* NOTREACHED */
}
}
argc -= optind;
argv += optind;
if (!argc || (country != NULL && host != NULL))
usage();
/*
* If no host or country is specified, rely on referrals from IANA.
*/
if (host == NULL && country == NULL) {
if ((host = getenv("WHOIS_SERVER")) == NULL &&
(host = getenv("RA_SERVER")) == NULL) {
if (!(flags & WHOIS_QUICK))
flags |= WHOIS_RECURSE;
}
}
while (argc-- > 0) {
if (country != NULL) {
char *qnichost;
s_asprintf(&qnichost, "%s%s", country, QNICHOST_TAIL);
whois(*argv, qnichost, flags);
free(qnichost);
} else
whois(*argv, host != NULL ? host :
choose_server(*argv), flags);
argv++;
}
exit(0);
}
static const char *
choose_server(char *domain)
{
size_t len = strlen(domain);
int i;
for (i = 0; whoiswhere[i].suffix != NULL; i++) {
size_t suffix_len = strlen(whoiswhere[i].suffix);
if (len > suffix_len &&
strcasecmp(domain + len - suffix_len,
whoiswhere[i].suffix) == 0)
return (whoiswhere[i].server);
}
errx(EX_SOFTWARE, "no default whois server");
}
static struct addrinfo *
gethostinfo(char const *host, int exit_on_noname)
{
struct addrinfo hints, *res;
int error;
memset(&hints, 0, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
res = NULL;
error = getaddrinfo(host, port, &hints, &res);
if (error && (exit_on_noname || error != EAI_NONAME))
err(EX_NOHOST, "%s: %s", host, gai_strerror(error));
return (res);
}
/*
* Wrapper for asprintf(3) that exits on error.
*/
static void
s_asprintf(char **ret, const char *format, ...)
{
va_list ap;
va_start(ap, format);
if (vasprintf(ret, format, ap) == -1) {
va_end(ap);
err(EX_OSERR, "vasprintf()");
}
va_end(ap);
}
static int
connect_to_any_host(struct addrinfo *hostres)
{
struct addrinfo *res;
nfds_t i, j;
size_t count;
struct pollfd *fds;
int timeout = 180, s = -1;
for (res = hostres, count = 0; res; res = res->ai_next)
count++;
fds = calloc(count, sizeof(*fds));
if (fds == NULL)
err(EX_OSERR, "calloc()");
/*
* Traverse the result list elements and make non-block
* connection attempts.
*/
count = i = 0;
for (res = hostres; res != NULL; res = res->ai_next) {
s = socket(res->ai_family, res->ai_socktype | SOCK_NONBLOCK,
res->ai_protocol);
if (s < 0)
continue;
if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
if (errno == EINPROGRESS) {
/* Add the socket to poll list */
fds[i].fd = s;
fds[i].events = POLLERR | POLLHUP |
POLLIN | POLLOUT;
count++;
i++;
} else {
close(s);
s = -1;
/*
* Poll only if we have something to poll,
* otherwise just go ahead and try next
* address
*/
if (count == 0)
continue;
}
} else
goto done;
/*
* If we are at the last address, poll until a connection is
* established or we failed all connection attempts.
*/
if (res->ai_next == NULL)
timeout = INFTIM;
/*
* Poll the watched descriptors for successful connections:
* if we still have more untried resolved addresses, poll only
* once; otherwise, poll until all descriptors have errors,
* which will be considered as ETIMEDOUT later.
*/
do {
int n;
n = poll(fds, i, timeout);
if (n == 0) {
/*
* No event reported in time. Try with a
* smaller timeout (but cap at 2-3ms)
* after a new host have been added.
*/
if (timeout >= 3)
timeout <<= 1;
break;
} else if (n < 0) {
/*
* errno here can only be EINTR which we would
* want to clean up and bail out.
*/
s = -1;
goto done;
}
/*
* Check for the event(s) we have seen.
*/
for (j = 0; j < i; j++) {
if (fds[j].fd == -1 || fds[j].events == 0 ||
fds[j].revents == 0)
continue;
if (fds[j].revents & ~(POLLIN | POLLOUT)) {
close(s);
fds[j].fd = -1;
fds[j].events = 0;
count--;
continue;
} else if (fds[j].revents & (POLLIN | POLLOUT)) {
/* Connect succeeded. */
s = fds[j].fd;
goto done;
}
}
} while (timeout == INFTIM && count != 0);
}
/* All attempts were failed */
s = -1;
if (count == 0)
errno = ETIMEDOUT;
done:
/* Close all watched fds except the succeeded one */
for (j = 0; j < i; j++)
if (fds[j].fd != s && fds[j].fd != -1)
close(fds[j].fd);
free(fds);
return (s);
}
static void
whois(const char *query, const char *hostname, int flags)
{
FILE *fp;
struct addrinfo *hostres;
char *buf, *host, *nhost, *p;
int s, f;
size_t len, i;
hostres = gethostinfo(hostname, 1);
s = connect_to_any_host(hostres);
if (s == -1)
err(EX_OSERR, "connect()");
/* Restore default blocking behavior. */
if ((f = fcntl(s, F_GETFL)) == -1)
err(EX_OSERR, "fcntl()");
f &= ~O_NONBLOCK;
if (fcntl(s, F_SETFL, f) == -1)
err(EX_OSERR, "fcntl()");
fp = fdopen(s, "r+");
if (fp == NULL)
err(EX_OSERR, "fdopen()");
if (!(flags & WHOIS_SPAM_ME) &&
(strcasecmp(hostname, DENICHOST) == 0 ||
strcasecmp(hostname, "de" QNICHOST_TAIL) == 0)) {
const char *q;
int idn = 0;
for (q = query; *q != '\0'; q++)
if (!isascii(*q))
idn = 1;
fprintf(fp, "-T dn%s %s\r\n", idn ? "" : ",ace", query);
} else if (!(flags & WHOIS_SPAM_ME) &&
(strcasecmp(hostname, DKNICHOST) == 0 ||
strcasecmp(hostname, "dk" QNICHOST_TAIL) == 0))
fprintf(fp, "--show-handles %s\r\n", query);
else if ((flags & WHOIS_SPAM_ME) ||
strchr(query, ' ') != NULL)
fprintf(fp, "%s\r\n", query);
else if (strcasecmp(hostname, ANICHOST) == 0) {
if (strncasecmp(query, "AS", 2) == 0 &&
strspn(query+2, "0123456789") == strlen(query+2))
fprintf(fp, "+ a %s\r\n", query+2);
else
fprintf(fp, "+ %s\r\n", query);
} else if (strcasecmp(hostres->ai_canonname, VNICHOST) == 0)
fprintf(fp, "domain %s\r\n", query);
else
fprintf(fp, "%s\r\n", query);
fflush(fp);
nhost = NULL;
while ((buf = fgetln(fp, &len)) != NULL) {
/* Nominet */
if (!(flags & WHOIS_SPAM_ME) &&
len == 5 && strncmp(buf, "-- \r\n", 5) == 0)
break;
printf("%.*s", (int)len, buf);
if ((flags & WHOIS_RECURSE) && nhost == NULL) {
for (i = 0; whois_referral[i].prefix != NULL; i++) {
p = buf;
SCAN(p, buf+len, *p == ' ');
if (strncasecmp(p, whois_referral[i].prefix,
whois_referral[i].len) != 0)
continue;
p += whois_referral[i].len;
SCAN(p, buf+len, *p == ' ');
host = p;
SCAN(p, buf+len, ishost(*p));
/* avoid loops */
if (strncmp(hostname, host, p - host) != 0)
s_asprintf(&nhost, "%.*s",
(int)(p - host), host);
break;
}
for (i = 0; actually_arin[i] != NULL; i++) {
if (strncmp(buf, actually_arin[i], len) == 0) {
s_asprintf(&nhost, "%s", ANICHOST);
break;
}
}
}
/* Verisign etc. */
if (!(flags & WHOIS_SPAM_ME) &&
len >= sizeof(CHOPSPAM)-1 &&
(strncasecmp(buf, CHOPSPAM, sizeof(CHOPSPAM)-1) == 0 ||
strncasecmp(buf, CHOPSPAM+4, sizeof(CHOPSPAM)-5) == 0)) {
printf("\n");
break;
}
}
fclose(fp);
freeaddrinfo(hostres);
if (nhost != NULL) {
whois(query, nhost, flags);
free(nhost);
}
}
static void
usage(void)
{
fprintf(stderr,
"usage: whois [-aAbfgiIklmPQrRS] [-c country-code | -h hostname] "
"[-p port] name ...\n");
exit(EX_USAGE);
}