1 /* 2 * Copyright (c) 2000 - 2004 Kungliga Tekniska H�gskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 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 * 17 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "kadmin_locl.h" 35 #ifdef HAVE_SYS_WAIT_H 36 #include <sys/wait.h> 37 #endif 38 39 RCSID("$Id: kadm_conn.c 16007 2005-09-01 18:49:57Z lha $"); 40 41 struct kadm_port { 42 char *port; 43 unsigned short def_port; 44 struct kadm_port *next; 45 } *kadm_ports; 46 47 static void 48 add_kadm_port(krb5_context context, const char *service, unsigned int port) 49 { 50 struct kadm_port *p; 51 p = malloc(sizeof(*p)); 52 if(p == NULL) { 53 krb5_warnx(context, "failed to allocate %lu bytes\n", 54 (unsigned long)sizeof(*p)); 55 return; 56 } 57 58 p->port = strdup(service); 59 p->def_port = port; 60 61 p->next = kadm_ports; 62 kadm_ports = p; 63 } 64 65 static void 66 add_standard_ports (krb5_context context) 67 { 68 add_kadm_port(context, "kerberos-adm", 749); 69 } 70 71 /* 72 * parse the set of space-delimited ports in `str' and add them. 73 * "+" => all the standard ones 74 * otherwise it's port|service[/protocol] 75 */ 76 77 void 78 parse_ports(krb5_context context, const char *str) 79 { 80 char p[128]; 81 82 while(strsep_copy(&str, " \t", p, sizeof(p)) != -1) { 83 if(strcmp(p, "+") == 0) 84 add_standard_ports(context); 85 else 86 add_kadm_port(context, p, 0); 87 } 88 } 89 90 static pid_t pgrp; 91 sig_atomic_t term_flag, doing_useful_work; 92 93 static RETSIGTYPE 94 sigchld(int sig) 95 { 96 int status; 97 waitpid(-1, &status, 0); 98 SIGRETURN(0); 99 } 100 101 static RETSIGTYPE 102 terminate(int sig) 103 { 104 if(getpid() == pgrp) { 105 /* parent */ 106 term_flag = 1; 107 signal(sig, SIG_IGN); 108 killpg(pgrp, sig); 109 } else { 110 /* child */ 111 if(doing_useful_work) 112 term_flag = 1; 113 else 114 exit(0); 115 } 116 SIGRETURN(0); 117 } 118 119 static int 120 spawn_child(krb5_context context, int *socks, int num_socks, int this_sock) 121 { 122 int e, i; 123 struct sockaddr_storage __ss; 124 struct sockaddr *sa = (struct sockaddr *)&__ss; 125 socklen_t sa_size = sizeof(__ss); 126 int s; 127 pid_t pid; 128 krb5_address addr; 129 char buf[128]; 130 size_t buf_len; 131 132 s = accept(socks[this_sock], sa, &sa_size); 133 if(s < 0) { 134 krb5_warn(context, errno, "accept"); 135 return 1; 136 } 137 e = krb5_sockaddr2address(context, sa, &addr); 138 if(e) 139 krb5_warn(context, e, "krb5_sockaddr2address"); 140 else { 141 e = krb5_print_address (&addr, buf, sizeof(buf), 142 &buf_len); 143 if(e) 144 krb5_warn(context, e, "krb5_print_address"); 145 else 146 krb5_warnx(context, "connection from %s", buf); 147 krb5_free_address(context, &addr); 148 } 149 150 pid = fork(); 151 if(pid == 0) { 152 for(i = 0; i < num_socks; i++) 153 close(socks[i]); 154 dup2(s, STDIN_FILENO); 155 dup2(s, STDOUT_FILENO); 156 if(s != STDIN_FILENO && s != STDOUT_FILENO) 157 close(s); 158 return 0; 159 } else { 160 close(s); 161 } 162 return 1; 163 } 164 165 static int 166 wait_for_connection(krb5_context context, 167 int *socks, int num_socks) 168 { 169 int i, e; 170 fd_set orig_read_set, read_set; 171 int max_fd = -1; 172 173 FD_ZERO(&orig_read_set); 174 175 for(i = 0; i < num_socks; i++) { 176 if (socks[i] >= FD_SETSIZE) 177 errx (1, "fd too large"); 178 FD_SET(socks[i], &orig_read_set); 179 max_fd = max(max_fd, socks[i]); 180 } 181 182 pgrp = getpid(); 183 184 if(setpgid(0, pgrp) < 0) 185 err(1, "setpgid"); 186 187 signal(SIGTERM, terminate); 188 signal(SIGINT, terminate); 189 signal(SIGCHLD, sigchld); 190 191 while (term_flag == 0) { 192 read_set = orig_read_set; 193 e = select(max_fd + 1, &read_set, NULL, NULL, NULL); 194 if(e < 0) { 195 if(errno != EINTR) 196 krb5_warn(context, errno, "select"); 197 } else if(e == 0) 198 krb5_warnx(context, "select returned 0"); 199 else { 200 for(i = 0; i < num_socks; i++) { 201 if(FD_ISSET(socks[i], &read_set)) 202 if(spawn_child(context, socks, num_socks, i) == 0) 203 return 0; 204 } 205 } 206 } 207 signal(SIGCHLD, SIG_IGN); 208 while(1) { 209 int status; 210 pid_t pid; 211 pid = waitpid(-1, &status, 0); 212 if(pid == -1 && errno == ECHILD) 213 break; 214 } 215 exit(0); 216 } 217 218 219 int 220 start_server(krb5_context context) 221 { 222 int e; 223 struct kadm_port *p; 224 225 int *socks = NULL, *tmp; 226 int num_socks = 0; 227 int i; 228 229 for(p = kadm_ports; p; p = p->next) { 230 struct addrinfo hints, *ai, *ap; 231 char portstr[32]; 232 memset (&hints, 0, sizeof(hints)); 233 hints.ai_flags = AI_PASSIVE; 234 hints.ai_socktype = SOCK_STREAM; 235 236 e = getaddrinfo(NULL, p->port, &hints, &ai); 237 if(e) { 238 snprintf(portstr, sizeof(portstr), "%u", p->def_port); 239 e = getaddrinfo(NULL, portstr, &hints, &ai); 240 } 241 242 if(e) { 243 krb5_warn(context, krb5_eai_to_heim_errno(e, errno), 244 "%s", portstr); 245 continue; 246 } 247 i = 0; 248 for(ap = ai; ap; ap = ap->ai_next) 249 i++; 250 tmp = realloc(socks, (num_socks + i) * sizeof(*socks)); 251 if(tmp == NULL) { 252 krb5_warnx(context, "failed to reallocate %lu bytes", 253 (unsigned long)(num_socks + i) * sizeof(*socks)); 254 continue; 255 } 256 socks = tmp; 257 for(ap = ai; ap; ap = ap->ai_next) { 258 int s = socket(ap->ai_family, ap->ai_socktype, ap->ai_protocol); 259 if(s < 0) { 260 krb5_warn(context, errno, "socket"); 261 continue; 262 } 263 264 socket_set_reuseaddr(s, 1); 265 socket_set_ipv6only(s, 1); 266 267 if (bind (s, ap->ai_addr, ap->ai_addrlen) < 0) { 268 krb5_warn(context, errno, "bind"); 269 close(s); 270 continue; 271 } 272 if (listen (s, SOMAXCONN) < 0) { 273 krb5_warn(context, errno, "listen"); 274 close(s); 275 continue; 276 } 277 socks[num_socks++] = s; 278 } 279 freeaddrinfo (ai); 280 } 281 if(num_socks == 0) 282 krb5_errx(context, 1, "no sockets to listen to - exiting"); 283 return wait_for_connection(context, socks, num_socks); 284 } 285