freebsd-skq/usr.bin/finger/net.c
Andras Olah 03801815df Allow the user to disable the use of T/TCP by setting the -T option.
This option becomes useless when all TCP stacks are fixed out there.
1996-03-15 16:41:49 +00:00

182 lines
5.2 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.
*/
#ifndef lint
static char sccsid[] = "@(#)net.c 8.3 (Berkeley) 1/2/94";
#endif /* not lint */
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <db.h>
#include <unistd.h>
#include <pwd.h>
#include <utmp.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <sys/uio.h>
#include "finger.h"
void
netfinger(name)
char *name;
{
extern int lflag;
extern int Tflag;
register FILE *fp;
register int c, lastc;
struct in_addr defaddr;
struct hostent *hp, def;
struct servent *sp;
struct sockaddr_in sin;
int s;
char *alist[1], *host;
struct iovec iov[3];
struct msghdr msg;
if (!(host = rindex(name, '@')))
return;
*host++ = NULL;
if (isdigit(*host) && (defaddr.s_addr = inet_addr(host)) != -1) {
def.h_name = host;
def.h_addr_list = alist;
def.h_addr = (char *)&defaddr;
def.h_length = sizeof(struct in_addr);
def.h_addrtype = AF_INET;
def.h_aliases = 0;
hp = &def;
} else if (!(hp = gethostbyname(host))) {
(void)fprintf(stderr,
"finger: unknown host: %s\n", host);
return;
}
if (!(sp = getservbyname("finger", "tcp"))) {
(void)fprintf(stderr, "finger: tcp/finger: unknown service\n");
return;
}
sin.sin_family = hp->h_addrtype;
bcopy(hp->h_addr, (char *)&sin.sin_addr, hp->h_length);
sin.sin_port = sp->s_port;
if ((s = socket(hp->h_addrtype, SOCK_STREAM, 0)) < 0) {
perror("finger: socket");
return;
}
/* have network connection; identify the host connected with */
(void)printf("[%s]\n", hp->h_name);
msg.msg_name = (void *)&sin;
msg.msg_namelen = sizeof sin;
msg.msg_iov = iov;
msg.msg_iovlen = 0;
msg.msg_control = 0;
msg.msg_controllen = 0;
msg.msg_flags = MSG_EOF;
/* -l flag for remote fingerd */
if (lflag) {
iov[msg.msg_iovlen].iov_base = "/W ";
iov[msg.msg_iovlen++].iov_len = 3;
}
/* send the name followed by <CR><LF> */
iov[msg.msg_iovlen].iov_base = name;
iov[msg.msg_iovlen++].iov_len = strlen(name);
iov[msg.msg_iovlen].iov_base = "\r\n";
iov[msg.msg_iovlen++].iov_len = 2;
/* -T disables T/TCP: compatibility option to finger broken hosts */
if (Tflag && connect(s, (struct sockaddr *)&sin, sizeof (sin))) {
perror("finger: connect");
return;
}
if (sendmsg(s, &msg, MSG_EOF) < 0) {
perror("finger: sendmsg");
close(s);
return;
}
/*
* 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.
*/
if (fp = fdopen(s, "r")) {
int lastc = '\n';
while ((c = getc(fp)) != EOF) {
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 (lastc != '\n')
putchar('\n');
if (ferror(fp)) {
/*
* Assume that whatever it was set errno...
*/
perror("finger: read");
}
(void)fclose(fp);
}
}