1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Tony Nardo of the Johns Hopkins University/Applied Physics Lab. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)net.c 8.4 (Berkeley) 4/28/95 37 * $FreeBSD: src/usr.bin/finger/net.c,v 1.12.2.4 2002/12/16 08:41:28 roam Exp $ 38 */ 39 40 #include <sys/param.h> 41 #include <sys/socket.h> 42 #include <sys/uio.h> 43 #include <ctype.h> 44 #include <db.h> 45 #include <err.h> 46 #include <netdb.h> 47 #include <pwd.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 #include <utmp.h> 53 #include "finger.h" 54 55 static void cleanup(int sig); 56 static int do_protocol(const char *name, const struct addrinfo *ai); 57 static void trying(const struct addrinfo *ai); 58 59 void 60 netfinger(char *name) 61 { 62 int error, multi; 63 char *host; 64 struct addrinfo *ai, *ai0; 65 static struct addrinfo hint; 66 67 host = strrchr(name, '@'); 68 if (host == NULL) 69 return; 70 *host++ = '\0'; 71 signal(SIGALRM, cleanup); 72 alarm(TIME_LIMIT); 73 74 hint.ai_flags = AI_CANONNAME; 75 hint.ai_family = family; 76 hint.ai_socktype = SOCK_STREAM; 77 78 error = getaddrinfo(host, "finger", &hint, &ai0); 79 if (error) { 80 warnx("%s: %s", host, gai_strerror(error)); 81 return; 82 } 83 84 multi = (ai0->ai_next) != 0; 85 86 /* ai_canonname may not be filled in if the user specified an IP. */ 87 if (ai0->ai_canonname == 0) 88 printf("[%s]\n", host); 89 else 90 printf("[%s]\n", ai0->ai_canonname); 91 92 for (ai = ai0; ai != NULL; ai = ai->ai_next) { 93 if (multi) 94 trying(ai); 95 96 error = do_protocol(name, ai); 97 if (!error) 98 break; 99 } 100 alarm(0); 101 freeaddrinfo(ai0); 102 } 103 104 static int 105 do_protocol(const char *name, const struct addrinfo *ai) 106 { 107 int cnt, line_len, s; 108 FILE *fp; 109 int c, lastc; 110 struct iovec iov[3]; 111 struct msghdr msg; 112 static char slash_w[] = "/W "; 113 static char neteol[] = "\r\n"; 114 115 s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); 116 if (s < 0) { 117 warn("socket(%d, %d, %d)", ai->ai_family, ai->ai_socktype, 118 ai->ai_protocol); 119 return -1; 120 } 121 122 msg.msg_name = (void *)ai->ai_addr; 123 msg.msg_namelen = ai->ai_addrlen; 124 msg.msg_iov = iov; 125 msg.msg_iovlen = 0; 126 msg.msg_control = 0; 127 msg.msg_controllen = 0; 128 msg.msg_flags = 0; 129 130 /* -l flag for remote fingerd */ 131 if (lflag) { 132 iov[msg.msg_iovlen].iov_base = slash_w; 133 iov[msg.msg_iovlen++].iov_len = 3; 134 } 135 /* send the name followed by <CR><LF> */ 136 iov[msg.msg_iovlen].iov_base = strdup(name); 137 iov[msg.msg_iovlen++].iov_len = strlen(name); 138 iov[msg.msg_iovlen].iov_base = neteol; 139 iov[msg.msg_iovlen++].iov_len = 2; 140 141 /* 142 * -T disables data-on-SYN: compatibility option to finger broken 143 * hosts. Also, the implicit-open API is broken on IPv6, so do 144 * the explicit connect there, too. 145 */ 146 if ((Tflag || ai->ai_addr->sa_family == AF_INET6) 147 && connect(s, ai->ai_addr, ai->ai_addrlen) < 0) { 148 warn("connect"); 149 close(s); 150 return -1; 151 } 152 153 if (sendmsg(s, &msg, 0) < 0) { 154 warn("sendmsg"); 155 close(s); 156 return -1; 157 } 158 159 /* 160 * Read from the remote system; once we're connected, we assume some 161 * data. If none arrives, we hang until the user interrupts. 162 * 163 * If we see a <CR> or a <CR> with the high bit set, treat it as 164 * a newline; if followed by a newline character, only output one 165 * newline. 166 * 167 * Otherwise, all high bits are stripped; if it isn't printable and 168 * it isn't a space, we can simply set the 7th bit. Every ASCII 169 * character with bit 7 set is printable. 170 */ 171 lastc = 0; 172 if ((fp = fdopen(s, "r")) != NULL) { 173 cnt = 0; 174 line_len = 0; 175 while ((c = getc(fp)) != EOF) { 176 if (++cnt > OUTPUT_MAX) { 177 printf("\n\n Output truncated at %d bytes...\n", 178 cnt - 1); 179 break; 180 } 181 if (c == 0x0d) { 182 if (lastc == '\r') /* ^M^M - skip dupes */ 183 continue; 184 c = '\n'; 185 lastc = '\r'; 186 } else { 187 if (!(eightflag || isprint(c) || isspace(c))) { 188 c &= 0x7f; 189 c |= 0x40; 190 } 191 if (lastc != '\r' || c != '\n') 192 lastc = c; 193 else { 194 lastc = '\n'; 195 continue; 196 } 197 } 198 putchar(c); 199 if (c != '\n' && ++line_len > _POSIX2_LINE_MAX) { 200 putchar('\\'); 201 putchar('\n'); 202 lastc = '\r'; 203 } 204 if (lastc == '\n' || lastc == '\r') 205 line_len = 0; 206 } 207 if (ferror(fp)) { 208 /* 209 * Assume that whatever it was set errno... 210 */ 211 warn("reading from network"); 212 } 213 if (lastc != '\n') 214 putchar('\n'); 215 216 fclose(fp); 217 } 218 return 0; 219 } 220 221 static void 222 trying(const struct addrinfo *ai) 223 { 224 char buf[NI_MAXHOST]; 225 226 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof buf, 227 NULL, 0, NI_NUMERICHOST) != 0) 228 return; /* XXX can't happen */ 229 230 printf("Trying %s...\n", buf); 231 } 232 233 void 234 cleanup(int sig __unused) 235 { 236 #define ERRSTR "Timed out.\n" 237 write(STDERR_FILENO, ERRSTR, sizeof ERRSTR); 238 exit(1); 239 } 240 241