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 * $DragonFly: src/usr.bin/finger/net.c,v 1.3 2003/10/04 20:36:44 hmp Exp $ 39 */ 40 41 #include <sys/param.h> 42 #include <sys/socket.h> 43 #include <sys/uio.h> 44 #include <ctype.h> 45 #include <db.h> 46 #include <err.h> 47 #include <netdb.h> 48 #include <pwd.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include <unistd.h> 53 #include <utmp.h> 54 #include "finger.h" 55 56 extern int lflag; /* XXX finger.h? */ 57 extern int Tflag; /* XXX finger.h? */ 58 extern sa_family_t family; 59 60 static void cleanup(int sig);; 61 static int do_protocol(const char *name, const struct addrinfo *ai); 62 static void trying(const struct addrinfo *ai); 63 64 void 65 netfinger(char *name) 66 { 67 int error, multi; 68 char *host; 69 struct addrinfo *ai, *ai0; 70 static struct addrinfo hint; 71 72 host = strrchr(name, '@'); 73 if (host == 0) 74 return; 75 *host++ = '\0'; 76 signal(SIGALRM, cleanup); 77 alarm(TIME_LIMIT); 78 79 hint.ai_flags = AI_CANONNAME; 80 hint.ai_family = family; 81 hint.ai_socktype = SOCK_STREAM; 82 83 error = getaddrinfo(host, "finger", &hint, &ai0); 84 if (error) { 85 warnx("%s: %s", host, gai_strerror(error)); 86 return; 87 } 88 89 multi = (ai0->ai_next) != 0; 90 91 /* ai_canonname may not be filled in if the user specified an IP. */ 92 if (ai0->ai_canonname == 0) 93 printf("[%s]\n", host); 94 else 95 printf("[%s]\n", ai0->ai_canonname); 96 97 for (ai = ai0; ai != 0; ai = ai->ai_next) { 98 if (multi) 99 trying(ai); 100 101 error = do_protocol(name, ai); 102 if (!error) 103 break; 104 } 105 alarm(0); 106 freeaddrinfo(ai0); 107 } 108 109 static int 110 do_protocol(const char *name, const struct addrinfo *ai) 111 { 112 int cnt, line_len, s; 113 FILE *fp; 114 int c, lastc; 115 struct iovec iov[3]; 116 struct msghdr msg; 117 static char slash_w[] = "/W "; 118 static char neteol[] = "\r\n"; 119 120 s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); 121 if (s < 0) { 122 warn("socket(%d, %d, %d)", ai->ai_family, ai->ai_socktype, 123 ai->ai_protocol); 124 return -1; 125 } 126 127 msg.msg_name = (void *)ai->ai_addr; 128 msg.msg_namelen = ai->ai_addrlen; 129 msg.msg_iov = iov; 130 msg.msg_iovlen = 0; 131 msg.msg_control = 0; 132 msg.msg_controllen = 0; 133 msg.msg_flags = 0; 134 135 /* -l flag for remote fingerd */ 136 if (lflag) { 137 iov[msg.msg_iovlen].iov_base = slash_w; 138 iov[msg.msg_iovlen++].iov_len = 3; 139 } 140 /* send the name followed by <CR><LF> */ 141 iov[msg.msg_iovlen].iov_base = strdup(name); 142 iov[msg.msg_iovlen++].iov_len = strlen(name); 143 iov[msg.msg_iovlen].iov_base = neteol; 144 iov[msg.msg_iovlen++].iov_len = 2; 145 146 /* 147 * -T disables data-on-SYN: compatibility option to finger broken 148 * hosts. Also, the implicit-open API is broken on IPv6, so do 149 * the explicit connect there, too. 150 */ 151 if ((Tflag || ai->ai_addr->sa_family == AF_INET6) 152 && connect(s, ai->ai_addr, ai->ai_addrlen) < 0) { 153 warn("connect"); 154 close(s); 155 return -1; 156 } 157 158 if (sendmsg(s, &msg, 0) < 0) { 159 warn("sendmsg"); 160 close(s); 161 return -1; 162 } 163 164 /* 165 * Read from the remote system; once we're connected, we assume some 166 * data. If none arrives, we hang until the user interrupts. 167 * 168 * If we see a <CR> or a <CR> with the high bit set, treat it as 169 * a newline; if followed by a newline character, only output one 170 * newline. 171 * 172 * Otherwise, all high bits are stripped; if it isn't printable and 173 * it isn't a space, we can simply set the 7th bit. Every ASCII 174 * character with bit 7 set is printable. 175 */ 176 lastc = 0; 177 if ((fp = fdopen(s, "r")) != NULL) { 178 cnt = 0; 179 line_len = 0; 180 while ((c = getc(fp)) != EOF) { 181 if (++cnt > OUTPUT_MAX) { 182 printf("\n\n Output truncated at %d bytes...\n", 183 cnt - 1); 184 break; 185 } 186 if (c == 0x0d) { 187 if (lastc == '\r') /* ^M^M - skip dupes */ 188 continue; 189 c = '\n'; 190 lastc = '\r'; 191 } else { 192 if (!isprint(c) && !isspace(c)) { 193 c &= 0x7f; 194 c |= 0x40; 195 } 196 if (lastc != '\r' || c != '\n') 197 lastc = c; 198 else { 199 lastc = '\n'; 200 continue; 201 } 202 } 203 putchar(c); 204 if (c != '\n' && ++line_len > _POSIX2_LINE_MAX) { 205 putchar('\\'); 206 putchar('\n'); 207 lastc = '\r'; 208 } 209 if (lastc == '\n' || lastc == '\r') 210 line_len = 0; 211 } 212 if (ferror(fp)) { 213 /* 214 * Assume that whatever it was set errno... 215 */ 216 warn("reading from network"); 217 } 218 if (lastc != '\n') 219 putchar('\n'); 220 221 fclose(fp); 222 } 223 return 0; 224 } 225 226 static void 227 trying(const struct addrinfo *ai) 228 { 229 char buf[NI_MAXHOST]; 230 231 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof buf, 232 (char *)0, 0, NI_NUMERICHOST) != 0) 233 return; /* XXX can't happen */ 234 235 printf("Trying %s...\n", buf); 236 } 237 238 void 239 cleanup(int sig __unused) 240 { 241 #define ERRSTR "Timed out.\n" 242 write(STDERR_FILENO, ERRSTR, sizeof ERRSTR); 243 exit(1); 244 } 245 246