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 37 #include <sys/cdefs.h> 38 39 __FBSDID("$FreeBSD$"); 40 41 #ifndef lint 42 static const char sccsid[] = "@(#)net.c 8.4 (Berkeley) 4/28/95"; 43 #endif 44 45 #include <sys/param.h> 46 #include <sys/socket.h> 47 #include <sys/uio.h> 48 #include <ctype.h> 49 #include <db.h> 50 #include <err.h> 51 #include <netdb.h> 52 #include <pwd.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <unistd.h> 57 #include <utmp.h> 58 #include "finger.h" 59 60 extern int lflag; /* XXX finger.h? */ 61 extern int Tflag; /* XXX finger.h? */ 62 63 static void cleanup(int sig);; 64 static int do_protocol(const char *name, const struct addrinfo *ai); 65 static void trying(const struct addrinfo *ai); 66 67 void 68 netfinger(name) 69 char *name; 70 { 71 int error, multi; 72 char *host; 73 struct addrinfo *ai, *ai0; 74 static struct addrinfo hint; 75 76 host = strrchr(name, '@'); 77 if (host == 0) 78 return; 79 *host++ = '\0'; 80 signal(SIGALRM, cleanup); 81 alarm(TIME_LIMIT); 82 83 hint.ai_flags = AI_CANONNAME; 84 hint.ai_family = PF_UNSPEC; 85 hint.ai_socktype = SOCK_STREAM; 86 87 error = getaddrinfo(host, "finger", &hint, &ai0); 88 if (error) { 89 warnx("%s: %s", host, gai_strerror(error)); 90 return; 91 } 92 93 multi = (ai0->ai_next) != 0; 94 95 /* ai_canonname may not be filled in if the user specified an IP. */ 96 if (ai0->ai_canonname == 0) 97 printf("[%s]\n", host); 98 else 99 printf("[%s]\n", ai0->ai_canonname); 100 101 for (ai = ai0; ai != 0; ai = ai->ai_next) { 102 if (multi) 103 trying(ai); 104 105 error = do_protocol(name, ai); 106 if (!error) 107 break; 108 } 109 alarm(0); 110 freeaddrinfo(ai0); 111 } 112 113 static int 114 do_protocol(const char *name, const struct addrinfo *ai) 115 { 116 int cnt, line_len, s; 117 FILE *fp; 118 int c, lastc; 119 struct iovec iov[3]; 120 struct msghdr msg; 121 static char slash_w[] = "/W "; 122 static char neteol[] = "\n\r"; 123 124 s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); 125 if (s < 0) { 126 warn("socket(%d, %d, %d)", ai->ai_family, ai->ai_socktype, 127 ai->ai_protocol); 128 return -1; 129 } 130 131 msg.msg_name = (void *)ai->ai_addr; 132 msg.msg_namelen = ai->ai_addrlen; 133 msg.msg_iov = iov; 134 msg.msg_iovlen = 0; 135 msg.msg_control = 0; 136 msg.msg_controllen = 0; 137 msg.msg_flags = 0; 138 139 /* -l flag for remote fingerd */ 140 if (lflag) { 141 iov[msg.msg_iovlen].iov_base = slash_w; 142 iov[msg.msg_iovlen++].iov_len = 3; 143 } 144 /* send the name followed by <CR><LF> */ 145 iov[msg.msg_iovlen].iov_base = strdup(name); 146 iov[msg.msg_iovlen++].iov_len = strlen(name); 147 iov[msg.msg_iovlen].iov_base = neteol; 148 iov[msg.msg_iovlen++].iov_len = 2; 149 150 /* 151 * -T disables data-on-SYN: compatibility option to finger broken 152 * hosts. Also, the implicit-open API is broken on IPv6, so do 153 * the explicit connect there, too. 154 */ 155 if ((Tflag || ai->ai_addr->sa_family == AF_INET6) 156 && connect(s, ai->ai_addr, ai->ai_addrlen) < 0) { 157 warn("connect"); 158 close(s); 159 return -1; 160 } 161 162 if (sendmsg(s, &msg, 0) < 0) { 163 warn("sendmsg"); 164 close(s); 165 return -1; 166 } 167 168 /* 169 * Read from the remote system; once we're connected, we assume some 170 * data. If none arrives, we hang until the user interrupts. 171 * 172 * If we see a <CR> or a <CR> with the high bit set, treat it as 173 * a newline; if followed by a newline character, only output one 174 * newline. 175 * 176 * Otherwise, all high bits are stripped; if it isn't printable and 177 * it isn't a space, we can simply set the 7th bit. Every ASCII 178 * character with bit 7 set is printable. 179 */ 180 lastc = 0; 181 if ((fp = fdopen(s, "r")) != NULL) { 182 cnt = 0; 183 line_len = 0; 184 while ((c = getc(fp)) != EOF) { 185 if (++cnt > OUTPUT_MAX) { 186 printf("\n\n Output truncated at %d bytes...\n", 187 cnt - 1); 188 break; 189 } 190 if (c == 0x0d) { 191 if (lastc == '\r') /* ^M^M - skip dupes */ 192 continue; 193 c = '\n'; 194 lastc = '\r'; 195 } else { 196 if (!isprint(c) && !isspace(c)) { 197 c &= 0x7f; 198 c |= 0x40; 199 } 200 if (lastc != '\r' || c != '\n') 201 lastc = c; 202 else { 203 lastc = '\n'; 204 continue; 205 } 206 } 207 putchar(c); 208 if (c != '\n' && ++line_len > _POSIX2_LINE_MAX) { 209 putchar('\\'); 210 putchar('\n'); 211 lastc = '\r'; 212 } 213 if (lastc == '\n' || lastc == '\r') 214 line_len = 0; 215 } 216 if (ferror(fp)) { 217 /* 218 * Assume that whatever it was set errno... 219 */ 220 warn("reading from network"); 221 } 222 if (lastc != '\n') 223 putchar('\n'); 224 225 fclose(fp); 226 } 227 return 0; 228 } 229 230 static void 231 trying(const struct addrinfo *ai) 232 { 233 char buf[NI_MAXHOST]; 234 235 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, buf, sizeof buf, 236 (char *)0, 0, NI_NUMERICHOST) != 0) 237 return; /* XXX can't happen */ 238 239 printf("Trying %s...\n", buf); 240 } 241 242 void 243 cleanup(int sig __unused) 244 { 245 #define ERRSTR "Timed out.\n" 246 write(STDERR_FILENO, ERRSTR, sizeof ERRSTR); 247 exit(1); 248 } 249 250