/src/qsnet/mqshd.c
C | 523 lines | 305 code | 88 blank | 130 comment | 72 complexity | 887e2c21394dff279c876e5a3321395d MD5 | raw file
1/*****************************************************************************\ 2 * $Id$ 3 ***************************************************************************** 4 * Copyright (C) 2001-2006 The Regents of the University of California. 5 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). 6 * Written by Jim Garlick <garlick@llnl.gov>. 7 * UCRL-CODE-2003-005. 8 * 9 * This file is part of Pdsh, a parallel remote shell program. 10 * For details, see <http://www.llnl.gov/linux/pdsh/>. 11 * 12 * Pdsh is free software; you can redistribute it and/or modify it under 13 * the terms of the GNU General Public License as published by the Free 14 * Software Foundation; either version 2 of the License, or (at your option) 15 * any later version. 16 * 17 * Pdsh is distributed in the hope that it will be useful, but WITHOUT ANY 18 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 19 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 20 * details. 21 * 22 * You should have received a copy of the GNU General Public License along 23 * with Pdsh; if not, write to the Free Software Foundation, Inc., 24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 25\*****************************************************************************/ 26 27/*- 28 * Started with BSD rshd which is: 29 * 30 * Copyright (c) 1988, 1989 The Regents of the University of California. 31 * All rights reserved. 32 * 33 * Redistribution and use in source and binary forms, with or without 34 * modification, are permitted provided that the following conditions 35 * are met: 36 * 1. Redistributions of source code must retain the above copyright 37 * notice, this list of conditions and the following disclaimer. 38 * 39 * 2. Redistributions in binary form must reproduce the above copyright 40 * notice, this list of conditions and the following disclaimer in the 41 * documentation and/or other materials provided with the distribution. 42 * 43 * 3. All advertising materials mentioning features or use of this software 44 * must display the following acknowledgement: 45 * This product includes software developed by the University of 46 * California, Berkeley and its contributors. 47 * 48 * 4. Neither the name of the University nor the names of its contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * 5. This is free software; you can redistribute it and/or modify it 53 * under the terms of the GNU General Public License as published 54 * by the Free Software Foundation; either version 2 of the 55 * License, or (at your option) any later version. 56 * 57 * 6. This is distributed in the hope that it will be useful, but 58 * WITHOUT ANY WARRANTY; without even the implied warranty of 59 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 60 * GNU General Public License for more details. 61 * 62 * 7. You should have received a copy of the GNU General Public License; 63 * if not, write to the Free Software Foundation, Inc., 59 Temple 64 * Place, Suite 330, Boston, MA 02111-1307 USA. 65 * 66 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 67 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 68 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 69 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 70 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 71 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 72 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 73 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 74 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 75 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 76 * SUCH DAMAGE. 77 */ 78 79/* 80 * PAM modifications by Michael K. Johnson <johnsonm@redhat.com> 81 */ 82 83char copyright[] = 84"@(#) Copyright (c) 1988, 1989, 2003 The Regents of the University of California.\n" 85"All rights reserved.\n"; 86 87/* 88 * From: @(#)mqshd.c 5.38 (Berkeley) 3/2/91 89 */ 90char rcsid[] = "$Id$"; 91/* #include "version.h" */ 92 93#if HAVE_CONFIG_H 94#include "config.h" 95#endif 96 97#if HAVE_UNISTD_H 98#include <unistd.h> 99#endif 100 101#include <fcntl.h> 102#include <sys/socket.h> /* connect */ 103#include <sys/types.h> 104#include <netinet/in.h> /* sockaddr_in, htons */ 105#include <arpa/inet.h> /* inet_ntoa */ 106#include <netdb.h> /* gethostbyname */ 107#include <net/if.h> /* struct ifconf, struct ifreq */ 108#include <sys/ioctl.h> /* ioctl */ 109#include <sys/param.h> /* MAXHOSTNAMELEN / INET_ADDRSTRLEN */ 110 111#include <stdio.h> 112#include <stdlib.h> 113#include <string.h> 114#include <syslog.h> 115#include <errno.h> 116#include <munge.h> 117 118#include "src/common/fd.h" 119#include "src/common/xmalloc.h" 120#include "qshell.h" 121 122#ifndef MAXHOSTNAMELEN 123#define MAXHOSTNAMELEN 64 124#endif 125 126#ifndef INET_ADDRSTRLEN 127#define INET_ADDRSTRLEN 16 128#endif 129 130#define MAX_MBUF_SIZE 4096 131 132extern int paranoid; 133extern int sent_null; 134 135#define ERRMSGLEN 4096 136static char errmsgbuf[ERRMSGLEN]; 137static const char *errmsg = NULL; 138 139#if USE_PAM 140extern char *pam_errmsg; 141#endif 142 143static char *munge_parse(char *buf, char *buf_end) { 144 int len = strlen(buf); 145 146 buf += (len + 1); 147 if (buf >= buf_end) { 148 syslog(LOG_ERR, "parser went beyond valid data"); 149 errmsg = "Internal Error"; 150 return NULL; 151 } 152 return buf; 153} 154 155static int getifrlen(struct ifreq *ifr) { 156 int len; 157 158 /* Calculations below are necessary b/c socket addresses can have 159 * variable length 160 */ 161 162#if HAVE_SA_LEN 163 if (sizeof(struct sockaddr) > ifr->ifr_addr.sa_len) 164 len = sizeof(struct sockaddr); 165 else 166 len = ifr->ifr_addr.sa_len; 167#else /* !HAVE_SA_LEN */ 168 /* For now we only assume AF_INET and AF_INET6 */ 169 switch(ifr->ifr_addr.sa_family) { 170#ifdef HAVE_IPV6 171 case AF_INET6: 172 len = sizeof(struct sockaddr_in6); 173 break; 174#endif /* HAVE_IPV6 */ 175 case AF_INET: 176 default: 177 len = sizeof(struct sockaddr_in); 178 break; 179 } 180 181 /* On ia32 struct sockaddr_in6/sockaddr_in was the largest 182 * structure in struct ifreq, but not on ia64. This fixes things 183 */ 184 if (len < (sizeof(struct ifreq) - IFNAMSIZ)) 185 len = sizeof(struct ifreq) - IFNAMSIZ; 186 187#endif /* HAVE_SA_LEN */ 188 189 return len; 190} 191 192static int check_interfaces(void *munge_addr, int addr_len) { 193 struct ifconf ifc; 194 struct ifreq *ifr; 195 int s, found = 0, lastlen = -1; 196 int len = sizeof(struct ifreq) * 100; 197 void *buf = NULL, *ptr = NULL; 198 struct sockaddr_in *sin; 199 char *addr; 200 201 /* Significant amounts of this code are from Unix Network 202 * Programming, by R. Stevens, Chapter 16 203 */ 204 205 if ((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) { 206 syslog(LOG_ERR, "socket call failed: %m"); 207 errmsg = "Internal System Error"; 208 goto bad; 209 } 210 211 /* get all active interfaces */ 212 while(1) { 213 if ((buf = (char *)malloc(len)) == NULL) { 214 syslog(LOG_ERR, "malloc failed: %m"); 215 errmsg = "Out of Memory"; 216 goto bad; 217 } 218 219 ifc.ifc_len = len; 220 ifc.ifc_buf = buf; 221 222 if (ioctl(s, SIOCGIFCONF, &ifc) < 0) { 223 syslog(LOG_ERR, "ioctl SIOCGIFCONF failed: %m"); 224 errmsg = "Internal System Error"; 225 goto bad; 226 } 227 else { 228 if (ifc.ifc_len == lastlen) 229 break; 230 231 lastlen = ifc.ifc_len; 232 } 233 234 /* Run ioctl() twice for portability reasons. See Unix Network 235 * Programming, section 16.6 236 */ 237 238 len += 10 * sizeof(struct ifreq); 239 free(buf); 240 } 241 242 /* get IP addresses for all interfaces */ 243 for (ptr = buf; ptr < buf + ifc.ifc_len; ) { 244 245 ifr = (struct ifreq *)ptr; 246 247 len = getifrlen(ifr); 248 249 ptr += sizeof(ifr->ifr_name) + len; 250 251 /* Currently, we only care about IPv4 (i.e. AF_INET) */ 252 if (ifr->ifr_addr.sa_family != AF_INET) 253 continue; 254 255 sin = (struct sockaddr_in *)&ifr->ifr_addr; 256 257 /* Skip 127.0.0.1 */ 258 addr = inet_ntoa(sin->sin_addr); 259 if (strcmp(addr,"127.0.0.1") == 0) 260 continue; 261 262 if (memcmp(munge_addr, (void *)&sin->sin_addr.s_addr, addr_len) == 0) { 263 found++; 264 break; 265 } 266 } 267 268 free(buf); 269 return found; 270 271bad: 272 free(buf); 273 return -1; 274} 275 276static int check_munge_ip(char *ip) { 277 struct in_addr in; 278 char ipbuf[INET_ADDRSTRLEN]; 279 280 strncpy(ipbuf, ip, INET_ADDRSTRLEN); 281 ipbuf[INET_ADDRSTRLEN-1] = '\0'; 282 283 if (inet_pton(AF_INET, ipbuf, &in) <= 0) { 284 syslog(LOG_ERR, "failed inet_pton: %m"); 285 errmsg = "Internal System Error"; 286 return -1; 287 } 288 289 return check_interfaces(&in, sizeof(struct in_addr)); 290} 291 292 293static void mqshell_get_args(struct sockaddr_in *fromp, 294 struct qshell_args *args) 295{ 296 struct sockaddr_in sin; 297 struct passwd cred; 298 int rv = -1; 299 int buf_length; 300 unsigned short port = 0; 301 unsigned int randnum; 302 char *mptr = NULL; 303 char *m_end = NULL; 304 char *m_head = NULL; 305 char mbuf[MAX_MBUF_SIZE]; 306 char cmdbuf[ARG_MAX + 1]; 307 308 errmsg = NULL; 309 310 args->sock = -1; 311 312 /* read munge blob for authentication */ 313 memset(&mbuf[0],0,sizeof(mbuf)); 314 if ((buf_length = fd_null_read_n(0, &mbuf[0], MAX_MBUF_SIZE)) < 0) { 315 syslog(LOG_ERR, "%s: %m", "mqshd: bad read error."); 316 errmsg = "Internal System Error"; 317 goto error_out; 318 } 319 320 if (buf_length == 0) { 321 syslog(LOG_ERR, "mqshd: null munge credential."); 322 errmsg = "Protocol Error"; 323 goto error_out; 324 } 325 326 /* 327 * The format of our munge buffer is as follows (each a string terminated 328 * with a '\0' (null): 329 * 330 * SIZE EXAMPLE 331 * ========== ============= 332 * remote_user_name variable "mhaskell" 333 * '\0' 334 * dotted_decimal_address_of_this_server 7-15 bytes "134.9.11.155" 335 * '\0' 336 * stderr_port_number 4-8 bytes "50111" 337 * '\0 338 * random number 1-8 bytes "1f79ca0e" 339 * '\0' 340 * users_command variable "ls -al" 341 * '\0' '\0' 342 * 343 */ 344 mptr = &mbuf[0]; 345 if ((rv = munge_decode(mbuf,0,(void **)&mptr,&buf_length, 346 &cred.pw_uid,&cred.pw_gid)) != EMUNGE_SUCCESS) { 347 348 syslog(LOG_ERR, "%s: %s", "munge_decode error", munge_strerror(rv)); 349 snprintf(errmsgbuf, ERRMSGLEN, "Authentication Failure: %s", 350 munge_strerror(rv)); 351 errmsg = &errmsgbuf[0]; 352 goto error_out; 353 } 354 355 if ((mptr == NULL) || (buf_length <= 0)) { 356 syslog(LOG_ERR, "Null munge buffer"); 357 errmsg = "Protocol Error"; 358 goto error_out; 359 } 360 361 m_head = mptr; 362 m_end = mptr + buf_length; 363 364 /* Verify User Id */ 365 366 if ((args->pwd = getpwnam_common(m_head)) == NULL) { 367 syslog(LOG_ERR, "bad getpwnam(): %m"); 368 errmsg = "Permission Denied"; 369 goto error_out; 370 } 371 372 if ((args->pwd->pw_uid != cred.pw_uid) && cred.pw_uid != 0) { 373 syslog(LOG_ERR, "failed credential check: %m"); 374 errmsg = "Permission Denied"; 375 goto error_out; 376 } 377 378 /* Verify IP address */ 379 380 if ((m_head = munge_parse(m_head, m_end)) == NULL) 381 goto error_out; 382 383 if ((rv = check_munge_ip(m_head)) < 0) 384 goto error_out; 385 386 if (rv == 0) { 387 syslog(LOG_ERR, "%s: %s", "Munge IP address doesn't match", m_head); 388 errmsg = "Permission Denied"; 389 goto error_out; 390 } 391 392 /* Verify Port */ 393 394 if ((m_head = munge_parse(m_head, m_end)) == NULL) 395 goto error_out; 396 397 errno = 0; 398 port = strtol(m_head, (char **)NULL, 10); 399 if (errno != 0) { 400 syslog(LOG_ERR, "%s: %s", "Bad port number from client", m_head); 401 errmsg = "Internal Error"; 402 goto error_out; 403 } 404 405 if (port != args->port) { 406 syslog(LOG_ERR, "%s: %d, %d", "Port mismatch", args->port, port); 407 errmsg = "Protocol Error"; 408 goto error_out; 409 } 410 411 /* Get Random Number */ 412 413 if ((m_head = munge_parse(m_head, m_end)) == NULL) 414 goto error_out; 415 416 errno = 0; 417 randnum = strtol(m_head,(char **)NULL,10); 418 if (errno != 0) { 419 syslog(LOG_ERR, "%s: %d", "mqshd: Bad random number from client.", randnum); 420 errmsg = "Internal Error"; 421 goto error_out; 422 } 423 424 if (args->port == 0 && randnum != 0) { 425 syslog(LOG_ERR,"protocol error, rand should be 0, %d", randnum); 426 errmsg = "Protocol Error"; 427 goto error_out; 428 } 429 430 /* Get Command */ 431 432 if ((m_head = munge_parse(m_head, m_end)) == NULL) 433 goto error_out; 434 435 if (strlen(m_head) < ARG_MAX) { 436 strncpy(&cmdbuf[0], m_head, sizeof(cmdbuf)); 437 cmdbuf[sizeof(cmdbuf) - 1] = '\0'; 438 } else { 439 syslog(LOG_ERR, "Not enough space for command: %s", m_head); 440 errmsg = "Command too long"; 441 goto error_out; 442 } 443 444 free(mptr); 445 mptr = NULL; 446 447 if ((args->hostname = findhostname(fromp)) == NULL) { 448 errmsg = "Host Address Mismatch"; 449 goto error_out; 450 } 451 452#ifdef USE_PAM 453 if (pamauth(args->pwd, "mqshell", args->pwd->pw_name, 454 args->hostname, args->pwd->pw_name ) < 0) { 455 syslog(LOG_ERR, "PAM failed authentication"); 456 errmsg = pam_errmsg; 457 goto error_out; 458 } 459#endif 460 461error_out: 462 463 /* If desired, setup stderr connection */ 464 args->sock = 0; 465 if (args->port != 0) { 466 char c; 467 468 if ((args->sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) { 469 syslog(LOG_ERR,"create socket: %m"); 470 goto bad; 471 } 472 sin.sin_family = AF_INET; 473 sin.sin_port = htons(args->port); 474 sin.sin_addr.s_addr = fromp->sin_addr.s_addr; 475 if (connect(args->sock, (struct sockaddr *)&sin, sizeof(sin)) < 0) { 476 syslog(LOG_ERR,"%s: %m","connect second port: %m"); 477 goto bad; 478 } 479 480 /* Sync with client to avoid race condition */ 481 rv = read(0,&c,1); 482 if (rv != 1 || c != '\0') { 483 syslog (LOG_ERR, "%s", "mqshd: Client not ready."); 484 goto bad; 485 } 486 } 487 488 if (errmsg != NULL) { 489 char buf[BUFSIZ], *bp = buf; 490 snprintf(bp, sizeof(buf)-1, "%c%s\n", '\01', errmsg); 491 fd_write_n(args->sock, buf, strlen(buf)); 492 goto bad; 493 } 494 495 /* Write random number to stderr */ 496 if (args->port != 0) { 497 randnum = htonl(randnum); 498 if ((rv = fd_write_n(args->sock, &randnum, sizeof(randnum))) == -1) { 499 syslog(LOG_ERR, "%s: %m", "write to stderr port: "); 500 error("Write error, %s\n", strerror(errno)); 501 goto bad; 502 } 503 } 504 505 args->remuser = NULL; 506 args->locuser = NULL; 507 args->cmdbuf = Strdup(cmdbuf); 508 509 return; 510 511bad: 512 free(mptr); 513 close(args->sock); 514 exit(1); 515} 516 517int main(int argc, char *argv[]) { 518 return qshell(argc, argv, &mqshell_get_args, "mqshd", 0); 519} 520 521/* 522 * vi: tabstop=4 shiftwidth=4 expandtab 523 */