fingerd.c revision 181269
11592Srgrimes/* 21592Srgrimes * Copyright (c) 1983, 1993 31592Srgrimes * The Regents of the University of California. All rights reserved. 41592Srgrimes * 51592Srgrimes * Redistribution and use in source and binary forms, with or without 61592Srgrimes * modification, are permitted provided that the following conditions 71592Srgrimes * are met: 81592Srgrimes * 1. Redistributions of source code must retain the above copyright 91592Srgrimes * notice, this list of conditions and the following disclaimer. 101592Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111592Srgrimes * notice, this list of conditions and the following disclaimer in the 121592Srgrimes * documentation and/or other materials provided with the distribution. 131592Srgrimes * 3. All advertising materials mentioning features or use of this software 141592Srgrimes * must display the following acknowledgement: 151592Srgrimes * This product includes software developed by the University of 161592Srgrimes * California, Berkeley and its contributors. 171592Srgrimes * 4. Neither the name of the University nor the names of its contributors 181592Srgrimes * may be used to endorse or promote products derived from this software 191592Srgrimes * without specific prior written permission. 201592Srgrimes * 211592Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221592Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231592Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241592Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251592Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261592Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271592Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281592Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291592Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301592Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311592Srgrimes * SUCH DAMAGE. 321592Srgrimes */ 331592Srgrimes 341592Srgrimes#ifndef lint 3531308Scharnierstatic const char copyright[] = 361592Srgrimes"@(#) Copyright (c) 1983, 1993\n\ 371592Srgrimes The Regents of the University of California. All rights reserved.\n"; 381592Srgrimes#endif /* not lint */ 391592Srgrimes 401592Srgrimes#ifndef lint 4131308Scharnier#if 0 421592Srgrimesstatic char sccsid[] = "@(#)fingerd.c 8.1 (Berkeley) 6/4/93"; 4331308Scharnier#endif 4412908Swollmanstatic const char rcsid[] = 4550476Speter "$FreeBSD: head/libexec/fingerd/fingerd.c 181269 2008-08-04 01:25:48Z cperciva $"; 461592Srgrimes#endif /* not lint */ 471592Srgrimes 4871274Sjedgar#include <sys/types.h> 4945393Sbrian#include <sys/param.h> 501592Srgrimes#include <sys/socket.h> 511592Srgrimes#include <netinet/in.h> 5212908Swollman#include <netinet/tcp.h> 531592Srgrimes#include <arpa/inet.h> 541592Srgrimes#include <errno.h> 551592Srgrimes 561592Srgrimes#include <unistd.h> 571592Srgrimes#include <syslog.h> 5871274Sjedgar#include <libutil.h> 591592Srgrimes#include <netdb.h> 601592Srgrimes#include <stdio.h> 611592Srgrimes#include <stdlib.h> 6297635Swollman#include <string.h> 631592Srgrimes#include "pathnames.h" 641592Srgrimes 65181269Scpercivavoid logerr(const char *, ...) __printflike(1, 2) __dead2; 661592Srgrimes 671592Srgrimesint 6890148Simpmain(int argc, char *argv[]) 691592Srgrimes{ 7090148Simp FILE *fp; 7190148Simp int ch; 7290148Simp char *lp; 7357313Sshin struct sockaddr_storage ss; 74141918Sstefanf socklen_t sval; 75141918Sstefanf int p[2], logging, pflag, secure; 761592Srgrimes#define ENTRIES 50 771592Srgrimes char **ap, *av[ENTRIES + 1], **comp, line[1024], *prog; 7845418Sbrian char rhost[MAXHOSTNAMELEN]; 791592Srgrimes 801592Srgrimes prog = _PATH_FINGER; 8198897Swollman logging = pflag = secure = 0; 821592Srgrimes openlog("fingerd", LOG_PID | LOG_CONS, LOG_DAEMON); 831592Srgrimes opterr = 0; 8498897Swollman while ((ch = getopt(argc, argv, "lp:s")) != -1) 851592Srgrimes switch (ch) { 861592Srgrimes case 'l': 871592Srgrimes logging = 1; 881592Srgrimes break; 891592Srgrimes case 'p': 901592Srgrimes prog = optarg; 9198897Swollman pflag = 1; 921592Srgrimes break; 931592Srgrimes case 's': 941592Srgrimes secure = 1; 951592Srgrimes break; 961592Srgrimes case '?': 971592Srgrimes default: 9847291Speter logerr("illegal option -- %c", optopt); 991592Srgrimes } 1001592Srgrimes 10112908Swollman /* 10212908Swollman * Enable server-side Transaction TCP. 10312908Swollman */ 10412908Swollman { 10512908Swollman int one = 1; 10612908Swollman if (setsockopt(STDOUT_FILENO, IPPROTO_TCP, TCP_NOPUSH, &one, 10712908Swollman sizeof one) < 0) { 10812908Swollman logerr("setsockopt(TCP_NOPUSH) failed: %m"); 10912908Swollman } 11012908Swollman } 11112908Swollman 1121592Srgrimes if (!fgets(line, sizeof(line), stdin)) 1131592Srgrimes exit(1); 1148870Srgrimes 11598897Swollman if (logging || pflag) { 11698897Swollman sval = sizeof(ss); 11798897Swollman if (getpeername(0, (struct sockaddr *)&ss, &sval) < 0) 11898897Swollman logerr("getpeername: %s", strerror(errno)); 11998897Swollman realhostname_sa(rhost, sizeof rhost - 1, 12098897Swollman (struct sockaddr *)&ss, sval); 12198897Swollman rhost[sizeof(rhost) - 1] = '\0'; 12298897Swollman if (pflag) 12398897Swollman setenv("FINGERD_REMOTE_HOST", rhost, 1); 12498897Swollman } 12598897Swollman 12631168Ssef if (logging) { 12731168Ssef char *t; 12831168Ssef char *end; 12931168Ssef 13031168Ssef end = memchr(line, 0, sizeof(line)); 13131168Ssef if (end == NULL) { 13271274Sjedgar if ((t = malloc(sizeof(line) + 1)) == NULL) 13371274Sjedgar logerr("malloc: %s", strerror(errno)); 13431168Ssef memcpy(t, line, sizeof(line)); 13531168Ssef t[sizeof(line)] = 0; 13631168Ssef } else { 13771274Sjedgar if ((t = strdup(line)) == NULL) 13871274Sjedgar logerr("strdup: %s", strerror(errno)); 13931168Ssef } 14031168Ssef for (end = t; *end; end++) 14131168Ssef if (*end == '\n' || *end == '\r') 14231168Ssef *end = ' '; 14345393Sbrian syslog(LOG_NOTICE, "query from %s: `%s'", rhost, t); 14431168Ssef } 14531168Ssef 1461592Srgrimes comp = &av[1]; 14712728Speter av[2] = "--"; 14812728Speter for (lp = line, ap = &av[3];;) { 1491592Srgrimes *ap = strtok(lp, " \t\r\n"); 1501592Srgrimes if (!*ap) { 15112728Speter if (secure && ap == &av[3]) { 1521592Srgrimes puts("must provide username\r\n"); 1531592Srgrimes exit(1); 1541592Srgrimes } 1551592Srgrimes break; 1561592Srgrimes } 1571592Srgrimes if (secure && strchr(*ap, '@')) { 1586180Sphk puts("forwarding service denied\r\n"); 1591592Srgrimes exit(1); 1601592Srgrimes } 1611592Srgrimes 1621592Srgrimes /* RFC742: "/[Ww]" == "-l" */ 1631592Srgrimes if ((*ap)[0] == '/' && ((*ap)[1] == 'W' || (*ap)[1] == 'w')) { 1641592Srgrimes av[1] = "-l"; 1651592Srgrimes comp = &av[0]; 1661592Srgrimes } 16784454Sru else if (++ap == av + ENTRIES) { 16884454Sru *ap = NULL; 1691592Srgrimes break; 17084454Sru } 1711592Srgrimes lp = NULL; 1721592Srgrimes } 1731592Srgrimes 174127560Spjd if ((lp = strrchr(prog, '/')) != NULL) 1751592Srgrimes *comp = ++lp; 1761592Srgrimes else 1771592Srgrimes *comp = prog; 1781592Srgrimes if (pipe(p) < 0) 17912908Swollman logerr("pipe: %s", strerror(errno)); 1801592Srgrimes 1811592Srgrimes switch(vfork()) { 1821592Srgrimes case 0: 1831592Srgrimes (void)close(p[0]); 18498897Swollman if (p[1] != STDOUT_FILENO) { 18598897Swollman (void)dup2(p[1], STDOUT_FILENO); 1861592Srgrimes (void)close(p[1]); 1871592Srgrimes } 18898897Swollman dup2(STDOUT_FILENO, STDERR_FILENO); 18998897Swollman 1901592Srgrimes execv(prog, comp); 19198897Swollman write(STDERR_FILENO, prog, strlen(prog)); 19298897Swollman#define MSG ": cannot execute\n" 19398897Swollman write(STDERR_FILENO, MSG, strlen(MSG)); 19498897Swollman#undef MSG 1951592Srgrimes _exit(1); 1961592Srgrimes case -1: 19712908Swollman logerr("fork: %s", strerror(errno)); 1981592Srgrimes } 1991592Srgrimes (void)close(p[1]); 2001592Srgrimes if (!(fp = fdopen(p[0], "r"))) 20112908Swollman logerr("fdopen: %s", strerror(errno)); 2021592Srgrimes while ((ch = getc(fp)) != EOF) { 2031592Srgrimes if (ch == '\n') 2041592Srgrimes putchar('\r'); 2051592Srgrimes putchar(ch); 2061592Srgrimes } 2071592Srgrimes exit(0); 2081592Srgrimes} 2091592Srgrimes 2101592Srgrimes#include <stdarg.h> 2111592Srgrimes 2121592Srgrimesvoid 21312908Swollmanlogerr(const char *fmt, ...) 2141592Srgrimes{ 2151592Srgrimes va_list ap; 2161592Srgrimes va_start(ap, fmt); 2171592Srgrimes (void)vsyslog(LOG_ERR, fmt, ap); 2181592Srgrimes va_end(ap); 2191592Srgrimes exit(1); 2201592Srgrimes /* NOTREACHED */ 2211592Srgrimes} 222