net.c

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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.
 * 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.
 */
 
#include "precomp.h"
 
void
netfinger(char *name)
{
    extern int lflag;
    char c, lastc;
    struct in_addr defaddr;
    struct hostent *hp, def;
    struct servent *sp;
    struct sockaddr_in sin;
    SOCKET s;
    char *alist[1], *host;
 
    /* If this is a local request */
    if (!(host = rindex(name, '@')))
        return;
 
    *host++ = '\0';
    if (isdigit(*host) && (defaddr.s_addr = inet_addr(host)) != (unsigned long)-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)) == INVALID_SOCKET) {
        perror("finger: socket");
        return;
    }
 
    /* have network connection; identify the host connected with */
    (void)printf("[%s]\n", hp->h_name);
    if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
        fprintf(stderr, "finger: connect rc = %d", WSAGetLastError());
        (void)closesocket(s);
        return;
    }
 
    /* -l flag for remote fingerd  */
    if (lflag)
        send(s, "/W ", 3, 0);
    /* send the name followed by <CR><LF> */
    send(s, name, strlen(name), 0);
    send(s, "\r\n", 2, 0);
 
    /*
     * 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;
    while (recv(s, &c, 1, 0) == 1) {
        c &= 0x7f;
        if (c == 0x0d) {
            if (lastc == '\r')  /* ^M^M - skip dupes */
                continue;
            c = '\n';
            lastc = '\r';
        } else {
            if (!isprint(c) && !isspace(c))
                c |= 0x40;
            if (lastc != '\r' || c != '\n')
                lastc = c;
            else {
                lastc = '\n';
                continue;
            }
        }
        putchar(c);
    }
    if (lastc != '\n')
        putchar('\n');
    putchar('\n');
    (void)closesocket(s);
}