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/*
* 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.
* 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);
}
static void
cleanup(int sig __unused)
{
#define ERRSTR "Timed out.\n"
write(STDERR_FILENO, ERRSTR, sizeof ERRSTR);
exit(1);
}
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