1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161
|
/* $Id$
*
* redir - a utility for redirecting tcp connections
*
* Author: Nigel Metheringham
* Nigel.Metheringham@ThePLAnet.net
*
* Based on, but much modified from, code originally written by
* sammy@freenet.akron.oh.us - original header is below.
*
* redir is released under the GNU General Public license,
* version 2, or at your discretion, any later version.
*
*/
/* Redir, the code to which is below, is actually a horrible hack of my
* other cool network utility, daemon, which is actually a horrible hack
* of ora's using C sample code, 12.2.c. But, hey, they do something.
* (and that's the key.)
* -- Sammy (sammy@freenet.akron.oh.us)
*/
/* oh, incidentally, Sammy is now sammy@oh.verio.com */
/* 980601: dl9sau
* added some nice new features:
*
* --bind_addr=my.other.ip.address
* forces to use my.other.ip.address for the outgoing connection
*
* you can also specify, that redir listens not on all IP addresses of
* your system but only for the given one, i.e.:
* if my host has the addresses
* irc.thishost.my.domain and mail.thishost.my.domain
* but you want that your users do connect for the irc redir service
* only on irc.thishost.my.domain, then do it this way:
* redir irc.fu-berlin.de irc.thishost.mydomain:6667 6667
* my need was that:
* addr1.first.domain 6667 redirects to irc.first.net port 6667
* and addr2.second.domain 6667 redirects to irc.second.net port 6667
* while addr1 and addr2 are the same maschine and the ports can be equal.
*
* enjoy it!
* - thomas <thomas@x-berg.in-berlin.de>, <dl9sau@db0tud.ampr.org>
*
* btw: i tried without success implementing code for the following scenario:
* redir --force_addr irc.fu-berlin.de 6667 6667
* if "--force_addr" is given and a user connects to my system, that address
* of my system will be used on the outgoing connection that the user
* connected to.
* i was not successful to determine, to which of my addresses the user
* has connected.
*/
/* Peter Skliarouk (skliaroukp@geocites.com) added possibility to
automatically recognize failed services(hosts) and to continue maintain
connections to "survived" services(hosts) in round-robin manner.
If program recognized that an service failed it would try to connect
to it every predefined number of connections
BUGS:
1) Program accepts one port for all targets thus SERVICES=SERVERS
(I just need to change the way redir takes service arguments to
something servername:port)
2) No inetd support
3) No ftp support
4) One force addr for everyone (and transparent redir).
*/
#define VERSION "2.1.2"
#define MAXSERVERS 10 // MAX number of servers
#define ATTEMPTS 1000 // In case of failure attempt to reconnect every
#define READY 0 // Service is ready
#define EMPTYSTRING ((char*)NULL) // empty string
#define YES 1
#define NO 0
#define NOTinitialized 0
#define FAILED -1
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <getopt.h>
#include <syslog.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <errno.h>
#include <assert.h>
#ifdef USE_TCP_WRAPPERS
#include <tcpd.h>
#endif
#define debug(x) if (dodebug) fprintf(stderr, x)
#define debug1(x,y) if (dodebug) fprintf(stderr, x, y)
#define AND &&
#define OR ||
/* let's set up some globals... */
int dodebug = 0;
int dosyslog = 0;
unsigned char reuse_addr = 1;
unsigned char linger_opt = 0;
int isForceAddr;
char * ForceAddr;
struct sockaddr_in AddrOut;
int timeout = 0;
int ftp = 0;
int isTransProxy;
char * ident = NULL;
struct Service_ Service[MAXSERVERS];
int CurrentService;
#ifdef USE_TCP_WRAPPERS
struct request_info request;
int allow_severity = LOG_INFO;
int deny_severity = LOG_WARNING;
#endif /* USE_TCP_WRAPPERS */
#ifdef NEED_STRRCHR
#define strrchr rindex
#endif /* NEED_STRRCHR */
/* prototype anything needing it */
//void do_accept(int servsock, struct sockaddr_in *target);
struct Service_{
// if it is NULL we know there is no more services in the array.
char *sHostName;
// later I should add PORTNUMBER - see bugs.
int iPort;
int ServiceTimeOut;
struct sockaddr_in Socket;
// int InUse;
};
//void do_accept(int servsock, struct Service_ *Service);
void do_accept(int servsock);
int bindsock(char *addr, int port, int fail);
#ifdef NEED_STRDUP
char *
strdup(char * str)
{
char * result;
if (result = (char *) malloc(strlen(str) + 1))
strcpy(result, str);
return result;
}
#endif /* NEED_STRDUP */
void
redir_usage(char *name)
{
fprintf(stderr,"usage:\n");
fprintf(stderr,
"\t%s --lport=<n> --cport=<n> [options]\n",
name);
fprintf(stderr, "\t%s --inetd --cport=<n>\n", name);
fprintf(stderr, "\n\tOptions are:-\n");
fprintf(stderr, "\t\t--lport=<n>\t\tport to listen on\n");
fprintf(stderr, "\t\t--laddr=IP\t\taddress of interface to listen on\n");
fprintf(stderr, "\t\t--cport=<n>\t\tport to connect to\n");
fprintf(stderr, "\t\t--caddr=<host>\t\tremote host to connect to\n");
fprintf(stderr, "\t\t--inetd\t\trun from inetd\n");
fprintf(stderr, "\t\t--debug\t\toutput debugging info\n");
fprintf(stderr, "\t\t--timeout=<n>\tset timeout to n seconds\n");
fprintf(stderr, "\t\t--syslog\tlog messages to syslog\n");
fprintf(stderr, "\t\t--name=<str>\ttag syslog messages with 'str'\n");
#ifdef USE_TCP_WRAPPERS
fprintf(stderr, "\t\t \tAlso used as service name for TCP wrappers\n");
#endif /* USE_TCP_WRAPPERS */
fprintf(stderr, "\t\t--bind_addr=IP\tbind() outgoing IP to given addr\n");
fprintf(stderr, "\t\t--ftp\t\tredirect passive ftp connections\n");
fprintf(stderr, "\t\t--transproxy\trun in linux's transparent proxy mode\n");
fprintf(stderr, "\n\tVersion %s - $Id$\n", VERSION);
exit(2);
}
void
parse_args(int argc,
char * argv[],
struct Service_ * Services,
// int * target_port,
char ** local_addr,
int * local_port,
int * timeout,
int * dodebug,
int * inetd,
int * dosyslog,
char ** bind_addr,
int * ftp,
int * transproxy)
{
static struct option long_options[] = {
{"lport", required_argument, 0, 'l'},
{"laddr", required_argument, 0, 'a'},
{"cport", required_argument, 0, 'r'},
{"caddr", required_argument, 0, 'c'},
{"bind_addr", required_argument, 0, 'b'},
{"debug", no_argument, 0, 'd'},
{"timeout", required_argument, 0, 't'},
{"inetd", no_argument, 0, 'i'},
{"ident", required_argument, 0, 'n'},
{"name", required_argument, 0, 'n'},
{"syslog", no_argument, 0, 's'},
{"ftp", no_argument, 0, 'f'},
{"transproxy", no_argument, 0, 'p'},
{0,0,0,0} /* End marker */
};
int option_index = 0;
int tmp_port ;
int nService;
extern int optind;
int opt;
struct servent *portdesc;
char *lport = NULL;
char *tport = NULL;
int currentService ;
*local_addr = NULL;
// *target_addr = NULL;
// *target_port = 0;
*local_port = 0;
nService =0;
while ((opt = getopt_long(argc, argv, "disfpn:t:b:a:l:r:c:",
long_options, &option_index)) != -1) {
switch (opt) {
case 'a':
*local_addr = optarg;
break;
case 'l':
lport = optarg;
break;
case 'r':
tport = optarg;
break;
case 'c':
{
Services[nService].sHostName = optarg;
nService++;
break;
}
case 'b':
*bind_addr = optarg;
isForceAddr= YES;
break;
case 'd':
(*dodebug)++;
break;
case 't':
*timeout = atol(optarg);
break;
case 'i':
(*inetd)++;
break;
case 'n':
/* This is the ident which is added to syslog messages */
ident = optarg;
break;
case 's':
(*dosyslog)++;
break;
case 'f':
(*ftp)++;
break;
case 'p':
(*transproxy)++;
break;
default:
redir_usage(argv[0]);
exit(1);
break;
}
}
if(tport == NULL)
{
redir_usage(argv[0]);
exit(1);
}
tmp_port = 0;
portdesc = getservbyname(tport, "tcp");
if ( portdesc != NULL) // succesfull lookup of service name
{
tmp_port = ntohs(portdesc->s_port);
}
else
{
tmp_port=atol(tport);
}
for(currentService = 0; currentService<nService; currentService++)
{
Services[currentService].iPort= tmp_port;
}
/* only check local port if not running from inetd */
if(!(*inetd)) {
if(lport == NULL)
{
redir_usage(argv[0]);
exit(1);
}
if ((portdesc = getservbyname(lport, "tcp")) != NULL)
*local_port = ntohs(portdesc->s_port);
else
*local_port = atol(lport);
} /* if *inetd */
if (!ident) {
if ((ident = (char *) strrchr(argv[0], '/'))) {
ident++;
} else {
ident = argv[0];
}
}
openlog(ident, LOG_PID, LOG_DAEMON);
return;
}
/* with the --ftp option, this one changes passive mode replies from
the ftp server to point to a new redirector which we spawn */
void ftp_clean(int send, char *buf, unsigned long *bytes)
{
char *port_start;
int rporthi, lporthi;
int lportlo, rportlo;
int lport, rport;
int remip[4];
int localsock;
int socksize = sizeof(struct sockaddr_in);
int i;
struct sockaddr_in newsession;
struct sockaddr_in sockname;
/* is this a passive mode return ? */
if(strncmp(buf, "227", 3)) {
write(send, buf, (*bytes));
return;
}
/* get the outside interface so we can listen */
if(getsockname(send, (struct sockaddr *)&sockname, &socksize) != 0) {
perror("getsockname");
if (dosyslog)
syslog(LOG_ERR, "getsockname failed: %m");
exit(1);
}
/* parse the old address out of the buffer */
port_start = strchr(buf, '(');
sscanf(port_start, "(%d,%d,%d,%d,%d,%d", &remip[0], &remip[1],
&remip[2], &remip[3], &rporthi, &rportlo);
/* we need to listen on a port for the incoming connection.
we'll use this strategy. start at 32768 for hi byte, then
sweep using the low byte of our pid and try to bind 5 times.
if we can't bind to any of those ports, fail */
lporthi = 0x80;
lportlo = getpid() & 0xf0;
rport = (rporthi << 8) | rportlo;
for(i = 0, localsock = -1; ((localsock == -1) && (i < 5));
i++, lportlo++) {
lport = ((lporthi << 8) | lportlo) +1; /* weird off by 1 bug */
localsock = bindsock(inet_ntoa(sockname.sin_addr), lport, 1);
}
/* check to see if we bound */
if(localsock == -1) {
fprintf(stderr, "ftp: unable to bind new listening address\n");
exit(1);
}
(*bytes) = sprintf(buf, "227 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\n",
sockname.sin_addr.s_addr & 0xff,
(sockname.sin_addr.s_addr >> 8) & 0xff,
(sockname.sin_addr.s_addr >> 16) & 0xff,
sockname.sin_addr.s_addr >> 24, lporthi, lportlo);
newsession.sin_port = htons(rport);
newsession.sin_family = AF_INET;
newsession.sin_addr.s_addr = remip[0] | (remip[1] << 8)
| (remip[2] << 16) | (remip[3] << 24);
debug1("ftp server ip: %s\n", inet_ntoa(newsession.sin_addr));
debug1("ftp server port: %d\n", rport);
debug1("listening on port %d\n", lport);
debug1("listening on addr %s\n",
inet_ntoa(sockname.sin_addr));
/* now that we're bound and listening, we can safely send the new
passive string without fear of them getting a connection
refused. */
write(send, buf, (*bytes));
/* turn off ftp checking while the data connection is active */
ftp = 0;
//////////////////////////
/// Warning: the high-avialablility technique is not
/// applicable here, so this part of code is commented out
/// until further reviews.
// do_accept(localsock, &newsession);
close(localsock);
ftp = 1;
return;
}
void
copyloop(int insock,
int outsock,
int timeout_secs)
{
fd_set iofds;
fd_set c_iofds;
int max_fd; /* Maximum numbered fd used */
struct timeval timeout;
unsigned long bytes;
unsigned long bytes_in = 0;
unsigned long bytes_out = 0;
unsigned int start_time, end_time;
char buf[4096];
/* Record start time */
start_time = (unsigned int) time(NULL);
/* Set up timeout */
timeout.tv_sec = timeout_secs;
timeout.tv_usec = 0;
/* file descriptor bits */
FD_ZERO(&iofds);
FD_SET(insock, &iofds);
FD_SET(outsock, &iofds);
if (insock > outsock) {
max_fd = insock;
} else {
max_fd = outsock;
}
debug1("Entering copyloop() - timeout is %d\n", timeout_secs);
while(1) {
(void) memcpy(&c_iofds, &iofds, sizeof(iofds));
if (select(max_fd + 1,
&c_iofds,
(fd_set *)0,
(fd_set *)0,
(timeout_secs ? &timeout : NULL)) <= 0) {
/* syslog(LLEV,"connection timeout: %d sec",timeout.tv_sec);*/
break;
}
if(FD_ISSET(insock, &c_iofds)) {
if((bytes = read(insock, buf, sizeof(buf))) <= 0)
break;
if(write(outsock, buf, bytes) != bytes)
break;
bytes_out += bytes;
}
if(FD_ISSET(outsock, &c_iofds)) {
if((bytes = read(outsock, buf, sizeof(buf))) <= 0)
break;
/* if we're correcting for PASV on ftp redirections, then
fix buf and bytes to have the new address, among other
things */
if(ftp)
ftp_clean(insock, buf, &bytes);
else
if(write(insock, buf, bytes) != bytes)
break;
bytes_in += bytes;
}
}
debug("Leaving main copyloop\n");
/*
setsockopt(insock, SOL_SOCKET, SO_REUSEADDR, &reuse_addr, sizeof(reuse_addr));
setsockopt(insock, SOL_SOCKET, SO_LINGER, &linger_opt, sizeof(SO_LINGER));
setsockopt(outsock, SOL_SOCKET, SO_REUSEADDR, &reuse_addr, sizeof(reuse_addr));
setsockopt(outsock, SOL_SOCKET, SO_LINGER, &linger_opt, sizeof(SO_LINGER));
*/
shutdown(insock,0);
shutdown(outsock,0);
close(insock);
close(outsock);
debug("copyloop - sockets shutdown and closed\n");
end_time = (unsigned int) time(NULL);
debug1("copyloop - connect time: %8d seconds\n", end_time - start_time);
debug1("copyloop - transfer in: %8ld bytes\n", bytes_in);
debug1("copyloop - transfer out: %8ld bytes\n", bytes_out);
if (dosyslog) {
syslog(LOG_NOTICE, "disconnect %d secs, %ld in %ld out",
(end_time - start_time), bytes_in, bytes_out);
}
return;
}
// Socket initialization for connection to real server.
int InitializeSocket
(
int isTransProxy,
int isForceAddr,
struct sockaddr_in *AddrOut,
struct sockaddr_in *AddrClient
)
{
int targetsock;
// int val;
targetsock = socket(AF_INET, SOCK_STREAM, 0);
// set non-block mode
// val = 0;
// ioctl(targetsock,BLOCKING,&val);
if (targetsock==FAILED)
{
if (dodebug)
{
perror("target: socket");
}
if (dosyslog)
{
syslog(LOG_ERR, "socket failed: %m");
}
exit(1);
}
if(isTransProxy==YES) {
memcpy(AddrOut, AddrClient, sizeof(struct sockaddr_in));
AddrOut->sin_port = 0; // To choose port yourself.
}
if ((isForceAddr==YES) OR (isTransProxy==YES))
{
/*
this only makes sense if an outgoing IP addr has been forced;
at this point, we have a valid targetsock to bind() to..
also, if we're in transparent proxy mode, this option
never makes sense
*/
if (bind(targetsock, (struct sockaddr *) AddrOut,
sizeof(struct sockaddr_in)) < 0)
{
perror("bind_addr: cannot bind to forced outgoing addr");
if (dosyslog)
syslog(LOG_ERR, "bind failed: %m");
_exit(1);
}
debug1("outgoing IP is %s\n", inet_ntoa(AddrOut->sin_addr));
}
return(targetsock);
}
/* lwait for a connection and move into copyloop... again,
passive ftp's will call this, so we don't dupilcate it. */
//do_accept(int servsock, struct sockaddr_in *target)
void
do_accept(int servsock)
{
int clisock;
int targetsock;
struct sockaddr_in client;
int clientlen = sizeof(client);
struct sockaddr_in * target;
int isConnect;
int ServiceToTry;
int isConnected;
int isMoreServices;
// struct Service_ *Service // global structure
int SonCurrentService;
int isVacantSocket;
debug("top of accept loop\n");
if ((clisock = accept(servsock, (struct sockaddr *) &client,
&clientlen)) < 0)
{
perror("server: accept");
if (dosyslog)
{
syslog(LOG_ERR, "accept failed: %m");
}
exit(1);
}
//////////
///////// setsockopt(targetsock,SOL_SOCKET,SOCKET_KEEPALIVE,&val)
debug1("peer IP is %s\n", inet_ntoa(client.sin_addr));
debug1("peer socket is %d\n", client.sin_port);
/* CurrentService is global variable which shows
number of service to which last connection attempt was made */
/* The algorithm is:
Get request
Find first service not "in use" (nobody tries to connect to it)
Mark the service "in use"
Fork to serve the request (telling to grandchild to connect to that service)
Grandchild: if connection failed - mark the service as "failed", try next
service not "in use"
*/
// Looking for service not "in use"
ServiceToTry=CurrentService;
isMoreServices=YES; // to avoid deadlock
isVacantSocket=NO;
while((isMoreServices==YES) AND (isVacantSocket==NO))
{
if (Service[ServiceToTry].sHostName==EMPTYSTRING)
{
debug("Reached end of service's list\n");
ServiceToTry=0;
continue;
}
if (Service[ServiceToTry].ServiceTimeOut>0)
{
Service[ServiceToTry].ServiceTimeOut--;
/*
if (Service[ServiceToTry].ServiceTimeOut==0)
{
#pragma _CRI guard
Service[ServiceToTry].InUse=NO;
#pragma _CRI endguard
}
*/
ServiceToTry++;
if (ServiceToTry==CurrentService)
isMoreServices=NO;
continue;
}
/*
if (Service[ServiceToTry].InUse==YES)
{
ServiceToTry++;
// we should not set isMoreServices to NO if it failed -
// could be this is the only Service left and it has huge queue
// of connections to serve...
if (ServiceToTry==CurrentService)
{
// let's sleep for a second...
sleep(1);
}
continue;
}
*/
// Found vacant socket :-)
CurrentService++; // next time try to use another service
if (Service[CurrentService].sHostName==EMPTYSTRING)
{
debug("Reached end of service's list\n");
CurrentService=0;
}
debug1("Next service will be: %d\n",CurrentService);
isVacantSocket=YES;
}
if (isMoreServices==NO)
{
if (dosyslog)
syslog(LOG_ERR, "No available services!");
debug("No avialable services!\n");
return;
}
assert(isVacantSocket==YES);
/*
* Double fork here so we don't have to wait later
* This detaches us from our parent so that the parent
* does not need to pick up dead kids later.
*
* This needs to be done before the hosts_access stuff, because
* extended hosts_access options expect to be run from a child.
*/
switch(fork())
{
case -1: /* Error */
perror("(server) fork");
if (dosyslog)
syslog(LOG_ERR, "(server) fork failed: %m");
_exit(1);
case 0: /* Child */
break;
default: /* Parent */
{
int status;
/* Wait for child (who has forked off grandchild) */
(void) wait(&status);
/* Close sockets to prevent confusion */
close(clisock);
return;
}
}
/* We are now the first child. Fork again and exit */
switch(fork())
{
case -1: /* Error */
perror("(child) fork");
if (dosyslog)
syslog(LOG_ERR, "(child) fork failed: %m");
_exit(1);
case 0: /* Child */
break;
default: /* Parent */
_exit(0);
}
/* We are now the grandchild */
/* Grandchild: if connection to ServiceToTry
failed - mark the service as "failed", try next
service not "in use" */
#ifdef USE_TCP_WRAPPERS
request_init(&request, RQ_DAEMON, ident, RQ_FILE, clisock, 0);
sock_host(&request);
sock_hostname(&request);
sock_hostaddr(&request);
if (!hosts_access(&request)) {
refuse(&request);
_exit(0);
}
if (dosyslog){
syslog(LOG_INFO, "accepted connect from %s", eval_client(&request));
}
#endif /* USE_TCP_WRAPPERS */
targetsock=NOTinitialized;
target=NULL;
SonCurrentService=ServiceToTry;
isMoreServices=YES; // to avoid deadlock in trying the services
isConnected=NO;
while((isMoreServices==YES) AND (isConnected==NO))
{
if (Service[ServiceToTry].sHostName==EMPTYSTRING)
{
debug("Son: Reached end of service's list\n");
ServiceToTry=0;
continue;
}
if (targetsock==NOTinitialized)
{
targetsock=InitializeSocket(isTransProxy,isForceAddr,&AddrOut,&client);
}
if (Service[ServiceToTry].ServiceTimeOut>0)
{
ServiceToTry++;
if (ServiceToTry==SonCurrentService)
sleep(1);
continue;
}
// Trying to connect...
target=&(Service[ServiceToTry].Socket);
// let's mark the socket "in use"
isConnect=connect(targetsock, (struct sockaddr *) target,
sizeof(struct sockaddr_in));
//////////////////////////////////////
// Keep Alive - setsockopt(targetsock,SOL_SOCKET,SOCKET_KEEPALIVE,&val)
if (isConnect==FAILED)
{
// we need to rebuild socket
close(targetsock);
targetsock=NOTinitialized;
// perror("target: connect");
if (dosyslog)
syslog(LOG_ERR, "target: connect failed: %m");
debug1("Service %d failed\n",ServiceToTry);
Service[ServiceToTry].ServiceTimeOut=ATTEMPTS;
ServiceToTry++;
if (ServiceToTry==SonCurrentService)
{
// We couldn't just terminate the thread - we have
// client on hold... :-(
// Let's sleep and after that will see what we could do.
sleep(1);
}
continue;
}
// Connection established.
isConnected=YES;
}
debug1("connected to %s\n", inet_ntoa(target->sin_addr));
/* thanks to Anders Vannman for the fix to make proper syslogging
happen here... */
if (dosyslog) {
char tmp1[20], tmp2[20];
strcpy(tmp1, inet_ntoa(client.sin_addr));
strcpy(tmp2, inet_ntoa(target->sin_addr));
syslog(LOG_NOTICE, "connecting %s/%d to %s/%d",
tmp1, client.sin_port,
tmp2, target->sin_port);
}
copyloop(clisock, targetsock, timeout);
exit(0); /* Exit after copy */
}
/* bind to a new socket, we do this out here because passive-fixups
are going to call it too, and there's no sense dupliciting the
code. */
/* fail is true if we should just return a -1 on error, false if we
should bail. */
int bindsock(char *addr, int port, int fail)
{
int servsock;
struct sockaddr_in server;
/*
* Get a socket to work with. This socket will
* be in the Internet domain, and will be a
* stream socket.
*/
if ((servsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
if(fail) {
return -1;
}
else {
perror("server: socket");
if (dosyslog)
syslog(LOG_ERR, "socket failed: %m");
exit(1);
}
}
server.sin_family = AF_INET;
server.sin_port = htons(port);
if (addr != NULL) {
struct hostent *hp;
debug1("listening on %s\n", addr);
if ((hp = gethostbyname(addr)) == NULL) {
fprintf(stderr, "%s: cannot resolve hostname.\n", addr);
exit(1);
}
memcpy(&server.sin_addr, hp->h_addr, hp->h_length);
} else {
debug("local IP is default\n");
server.sin_addr.s_addr = htonl(inet_addr("0.0.0.0"));
}
setsockopt(servsock, SOL_SOCKET, SO_REUSEADDR, &reuse_addr, sizeof(reuse_addr));
setsockopt(servsock, SOL_SOCKET, SO_LINGER, &linger_opt, sizeof(SO_LINGER));
/*
* Try to bind the address to the socket.
*/
if (bind(servsock, (struct sockaddr *) &server,
sizeof(server)) < 0) {
if(fail) {
close(servsock);
return -1;
} else {
perror("server: bind");
if (dosyslog)
syslog(LOG_ERR, "bind failed: %m");
exit(1);
}
}
/*
* Listen on the socket.
*/
if (listen(servsock, 10000) < 0) {
if(fail) {
close(servsock);
return -1;
} else {
perror("server: listen");
if (dosyslog)
syslog(LOG_ERR, "listen failed: %m");
exit(1);
}
}
return servsock;
}
void BuildSocket(struct sockaddr_in *Socket,char *sHostName ,int iPort )
{
char* target_ip ;
Socket->sin_family = AF_INET;
Socket->sin_port = htons(iPort);
if (sHostName != NULL) {
struct hostent *hp;
debug1("target is %s\n", sHostName);
if ((hp = gethostbyname(sHostName)) == NULL) {
fprintf(stderr, "%s: host unknown.\n", sHostName);
exit(1);
}
memcpy(&Socket->sin_addr, hp->h_addr, hp->h_length);
} else {
debug("target is localhost\n");
Socket->sin_addr.s_addr = htonl(inet_addr("0.0.0.0"));
}
if (dodebug)
{
target_ip = NULL;
target_ip = strdup(inet_ntoa(Socket->sin_addr));
if(target_ip)
{
debug1("target IP address is %s\n", target_ip);
debug1("target port is %d\n", iPort);
}
}
}
void BuildServersSockets(struct Service_* Service){
// Seting up Service's sockets
int nService=0;
while(Service[nService].sHostName != EMPTYSTRING){
BuildSocket(&(Service[nService].Socket),Service[nService].sHostName,Service[nService].iPort);
nService++;
}
}
void InitServices(struct Service_* Service)
{
int nService;
if(Service)
{
for(nService=0; nService<MAXSERVERS; nService++)
{
Service[nService].sHostName=EMPTYSTRING;
Service[nService].ServiceTimeOut=READY;
}
}
}
int
main(int argc, char *argv[])
{
// struct sockaddr_in target;
// int target_port;
char *local_addr;
int local_port;
int inetd = 0;
// char * target_ip;
char * ip_to_target;
debug("parse args\n");
InitServices(Service);
isTransProxy=NO;
isForceAddr=NO;
ForceAddr=NULL;
// parse_args(argc, argv, Service, &target_port, &local_addr,
parse_args(argc, argv, Service, &local_addr,
&local_port, &timeout, &dodebug, &inetd, &dosyslog, &ForceAddr,
&ftp, &isTransProxy);
BuildServersSockets(Service);
/* Set up outgoing IP addr (optional);
* we have to wait for bind until targetsock = socket() is done
*/
if ((isForceAddr==YES) AND (isTransProxy==NO)) {
struct hostent *hp;
fprintf(stderr, "bind_addr is %s\n", ForceAddr);
AddrOut.sin_family = AF_INET;
AddrOut.sin_port = 0;
if ((hp = gethostbyname(ForceAddr)) == NULL) {
fprintf(stderr, "%s: cannot resolve forced outgoing IP address.\n", ForceAddr);
exit(1);
}
memcpy(&AddrOut.sin_addr, hp->h_addr, hp->h_length);
ip_to_target = strdup(inet_ntoa(AddrOut.sin_addr));
debug1("IP address for target is %s\n", ip_to_target);
}
if (inetd) {
//////////////////////
/// Warning!!!
/// INETD part not affected by the patch.
/// It probably doesn't work at all!!!!
//////////////////////
int targetsock;
struct sockaddr_in client;
int client_size = sizeof(client);
exit(1); // to prevent catastrophes
#ifdef USE_TCP_WRAPPERS
request_init(&request, RQ_DAEMON, ident, RQ_FILE, 0, 0);
sock_host(&request);
sock_hostname(&request);
sock_hostaddr(&request);
if (!hosts_access(&request))
refuse(&request);
#endif /* USE_TCP_WRAPPERS */
if (!getpeername(0, (struct sockaddr *) &client, &client_size)) {
debug1("peer IP is %s\n", inet_ntoa(client.sin_addr));
debug1("peer socket is %d\n", client.sin_port);
}
if ((targetsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
perror("target: socket");
if (dosyslog)
syslog(LOG_ERR, "targetsock failed: %m");
exit(1);
}
if(isTransProxy) {
memcpy(&AddrOut, &client, sizeof(struct sockaddr_in));
AddrOut.sin_port = 0;
}
if ((isForceAddr==YES) OR (isTransProxy==YES)) {
/* this only makes sense if an outgoing IP addr has been forced;
* at this point, we have a valid targetsock to bind() to.. */
if (bind(targetsock, (struct sockaddr *) &AddrOut,
sizeof(AddrOut)) < 0) {
perror("bind_addr: cannot bind to forcerd outgoing addr");
if (dosyslog)
syslog(LOG_ERR, "bind failed: %m");
exit(1);
}
debug1("outgoing IP is %s\n", inet_ntoa(AddrOut.sin_addr));
}
///////////////////
/// Warning!!!
/// The following code is completely commented out
/// because the whole INETD part was not patched.
/* if (connect(targetsock, (struct sockaddr *) &target,
sizeof(target)) < 0) {
perror("target: connect");
if (dosyslog)
syslog(LOG_ERR, "connect failed: %m");
exit(1);
}
if (dosyslog) {
syslog(LOG_NOTICE, "connecting %s/%d to %s/%d",
inet_ntoa(client.sin_addr), client.sin_port,
target_ip, target.sin_port);
}
*/
/* Just start copying - one side of the loop is stdin - 0 */
copyloop(0, targetsock, timeout);
/* End of inetd invocation */
} else {
/* if it is standalone daemon - continue here */
/* Let's listen for incoming connections */
int servsock;
if(local_addr)
servsock = bindsock(local_addr, local_port, 0);
else
servsock = bindsock(NULL, local_port, 0);
/*
* Accept connections. When we accept one, ns
* will be connected to the client. client will
* contain the address of the client.
*/
CurrentService=0; // global variable
while (1)
{
// do_accept(servsock, &target);
do_accept(servsock); // Service is global structure
}
}
/* this should really never be reached */
exit(0);
}
|