freebsd-dev/usr.bin/finger/net.c
Ed Schouten 550dcc5960 Migrate finger(1) towards utmpx.
It was already ported to use libulog, which makes it simpler now. Be
sure to catch the error returned by setutxdb(). Otherwise it may perform
a lookup on the utx.active database.
2010-01-13 17:50:58 +00:00

241 lines
6.1 KiB
C

/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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.
*/
#if 0
#ifndef lint
static char sccsid[] = "@(#)net.c 8.4 (Berkeley) 4/28/95";
#endif
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <ctype.h>
#include <db.h>
#include <err.h>
#include <netdb.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <utmpx.h>
#include "finger.h"
static void cleanup(int sig);
static int do_protocol(const char *name, const struct addrinfo *ai);
static void trying(const struct addrinfo *ai);
void
netfinger(char *name)
{
int error, multi;
char *host;
struct addrinfo *ai, *ai0;
static struct addrinfo hint;
host = strrchr(name, '@');
if (host == 0)
return;
*host++ = '\0';
signal(SIGALRM, cleanup);
alarm(TIME_LIMIT);
hint.ai_flags = AI_CANONNAME;
hint.ai_family = family;
hint.ai_socktype = SOCK_STREAM;
error = getaddrinfo(host, "finger", &hint, &ai0);
if (error) {
warnx("%s: %s", host, gai_strerror(error));
return;
}
multi = (ai0->ai_next) != 0;
/* ai_canonname may not be filled in if the user specified an IP. */
if (ai0->ai_canonname == 0)
printf("[%s]\n", host);
else
printf("[%s]\n", ai0->ai_canonname);
for (ai = ai0; ai != 0; ai = ai->ai_next) {
if (multi)
trying(ai);
error = do_protocol(name, ai);
if (!error)
break;
}
alarm(0);
freeaddrinfo(ai0);
}
static int
do_protocol(const char *name, const struct addrinfo *ai)
{
int cnt, line_len, s;
FILE *fp;
int c, lastc;
struct iovec iov[3];
struct msghdr msg;
static char slash_w[] = "/W ";
static char neteol[] = "\r\n";
s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (s < 0) {
warn("socket(%d, %d, %d)", ai->ai_family, ai->ai_socktype,
ai->ai_protocol);
return -1;
}
msg.msg_name = (void *)ai->ai_addr;
msg.msg_namelen = ai->ai_addrlen;
msg.msg_iov = iov;
msg.msg_iovlen = 0;
msg.msg_control = 0;
msg.msg_controllen = 0;
msg.msg_flags = 0;
/* -l flag for remote fingerd */
if (lflag) {
iov[msg.msg_iovlen].iov_base = slash_w;
iov[msg.msg_iovlen++].iov_len = 3;
}
/* send the name followed by <CR><LF> */
iov[msg.msg_iovlen].iov_base = strdup(name);
iov[msg.msg_iovlen++].iov_len = strlen(name);
iov[msg.msg_iovlen].iov_base = neteol;
iov[msg.msg_iovlen++].iov_len = 2;
if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0) {
warn("connect");
close(s);
return -1;
}
if (sendmsg(s, &msg, 0) < 0) {
warn("sendmsg");
close(s);
return -1;
}
/*
* Read from the remote system; once we're connected, we assume some
* data. If none arrives, we hang until the user interrupts.
*
* If we see a <CR> or a <CR> with the high bit set, treat it as
* a newline; if followed by a newline character, only output one
* newline.
*
* Otherwise, all high bits are stripped; if it isn't printable and
* it isn't a space, we can simply set the 7th bit. Every ASCII
* character with bit 7 set is printable.
*/
lastc = 0;
if ((fp = fdopen(s, "r")) != NULL) {
cnt = 0;
line_len = 0;
while ((c = getc(fp)) != EOF) {
if (++cnt > OUTPUT_MAX) {
printf("\n\n Output truncated at %d bytes...\n",
cnt - 1);
break;
}
if (c == 0x0d) {
if (lastc == '\r') /* ^M^M - skip dupes */
continue;
c = '\n';
lastc = '\r';
} else {
if (!isprint(c) && !isspace(c)) {
c &= 0x7f;
c |= 0x40;
}
if (lastc != '\r' || c != '\n')
lastc = c;
else {
lastc = '\n';
continue;
}
}
putchar(c);
if (c != '\n' && ++line_len > _POSIX2_LINE_MAX) {
putchar('\\');
putchar('\n');
lastc = '\r';
}
if (lastc == '\n' || lastc == '\r')
line_len = 0;
}
if (ferror(fp)) {
/*
* Assume that whatever it was set errno...
*/
warn("reading from network");
}
if (lastc != '\n')
putchar('\n');
fclose(fp);
}
return 0;
}
static void
trying(const struct addrinfo *ai)
{
char buf[NI_MAXHOST];
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof buf,
(char *)0, 0, NI_NUMERICHOST) != 0)
return; /* XXX can't happen */
printf("Trying %s...\n", buf);
}
void
cleanup(int sig __unused)
{
#define ERRSTR "Timed out.\n"
write(STDERR_FILENO, ERRSTR, sizeof ERRSTR);
exit(1);
}