eroute.c

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/*
 * manipulate eroutes
 * Copyright (C) 1996  John Ioannidis.
 * Copyright (C) 1997, 1998, 1999, 2000, 2001  Richard Guy Briggs.
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 */

char eroute_c_version[] = "RCSID $Id: eroute.c,v 1.43 2001/06/15 05:02:05 rgb Exp $";


#include <sys/types.h>
#include <linux/types.h> /* new */
#include <string.h>
#include <errno.h>
#include <stdlib.h> /* system(), strtoul() */

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <netdb.h>


#include <unistd.h>
#include <freeswan.h>
#if 0
#include <linux/autoconf.h>	/* CONFIG_IPSEC_PFKEYv2 */
#endif
/* permanently turn it on since netlink support has been disabled */
     #include <signal.h>
     #include <pfkeyv2.h>
     #include <pfkey.h>
#include "radij.h"
#include "ipsec_encap.h"
#include "ipsec_netlink.h"


#include <stdio.h>
#include <getopt.h>

char *program_name;
extern char *optarg;
extern int optind, opterr, optopt;
char *eroute_af_opt, *said_af_opt, *edst_opt, *spi_opt, *proto_opt, *said_opt, *dst_opt, *src_opt;
int action_type = 0;

extern unsigned int pfkey_lib_debug; /* used by libfreeswan/pfkey_v2_build */
int pfkey_sock;
fd_set pfkey_socks;
uint32_t pfkey_seq = 0;

static void
usage(char* arg)
{
	fprintf(stdout, "usage: %s --{add,replace} --eraf <inet | inet6> --src <src>/<srcmaskbits>|<srcmask> --dst <dst>/<dstmaskbits>|<dstmask> <SA>\n", arg);
	fprintf(stdout, "            where <SA> is '--af <inet | inet6> --edst <edst> --spi <spi> --proto <proto>' OR '--said <said>' OR '--said <%%passthrough | %%passthrough4 | %%passthrough6 | %%drop | %%reject | %%trap | %%hold | %%pass>'.\n");
	fprintf(stdout, "       %s --del --eraf <inet | inet6>--src <src>/<srcmaskbits>|<srcmask> --dst <dst>/<dstmaskbits>|<dstmask>\n", arg);
	fprintf(stdout, "       %s --clear\n", arg);
	fprintf(stdout, "       %s --help\n", arg);
	fprintf(stdout, "       %s --version\n", arg);
	fprintf(stdout, "       %s\n", arg);
	fprintf(stdout, "        [ --debug ] is optional to any %s command.\n", arg);
	fprintf(stdout, "        [ --label <label> ] is optional to any %s command.\n", arg);
exit(1);
}

static struct option const longopts[] =
{
	{"dst", 1, 0, 'D'},
	{"src", 1, 0, 'S'},
	{"eraf", 1, 0, 'f'},
	{"add", 0, 0, 'a'},
	{"replace", 0, 0, 'r'},
	{"clear", 0, 0, 'c'},
	{"del", 0, 0, 'd'},
	{"af", 1, 0, 'i'},
	{"edst", 1, 0, 'e'},
	{"proto", 1, 0, 'p'},
	{"help", 0, 0, 'h'},
	{"spi", 1, 0, 's'},
	{"said", 1, 0, 'I'},
	{"version", 0, 0, 'v'},
	{"label", 1, 0, 'l'},
	{"optionsfrom", 1, 0, '+'},
	{"debug", 0, 0, 'g'},
	{0, 0, 0, 0}
};

int
main(int argc, char **argv)
{
/*	int fd; */
	char *endptr;
/*	int ret; */
	int c, previous = -1;
	const char* error_s;
	int debug = 0;

	int error = 0;

	char ipaddr_txt[ADDRTOT_BUF];                
	struct sadb_ext *extensions[SADB_EXT_MAX + 1];
	struct sadb_msg *pfkey_msg;
	ip_address pfkey_address_s_ska;
	/*struct sockaddr_in pfkey_address_d_ska;*/
	ip_address pfkey_address_sflow_ska;
	ip_address pfkey_address_dflow_ska;
	ip_address pfkey_address_smask_ska;
	ip_address pfkey_address_dmask_ska;

	ip_said said;
	ip_subnet s_subnet, d_subnet;
 	int eroute_af = 0;
 	int said_af = 0;

	int argcount = argc;

	program_name = argv[0];
	eroute_af_opt = said_af_opt = edst_opt = spi_opt = proto_opt = said_opt = dst_opt = src_opt = NULL;

	while((c = getopt_long(argc, argv, ""/*"acdD:e:i:hprs:S:f:vl:+:g"*/, longopts, 0)) != EOF) {
		switch(c) {
		case 'g':
			debug = 1;
			pfkey_lib_debug = 1;
			argcount--;
			break;
		case 'a':
			if(action_type) {
				fprintf(stderr, "%s: Only one of '--add', '--replace', '--clear', or '--del' options permitted.\n",
					program_name);
				exit(1);
			}
			action_type = EMT_SETEROUTE;
			break;
		case 'r':
			if(action_type) {
				fprintf(stderr, "%s: Only one of '--add', '--replace', '--clear', or '--del' options permitted.\n",
					program_name);
				exit(1);
			}
			action_type = EMT_RPLACEROUTE;
			break;
		case 'c':
			if(action_type) {
				fprintf(stderr, "%s: Only one of '--add', '--replace', '--clear', or '--del' options permitted.\n",
					program_name);
				exit(1);
			}
			action_type = EMT_CLREROUTE;
			break;
		case 'd':
			if(action_type) {
				fprintf(stderr, "%s: Only one of '--add', '--replace', '--clear', or '--del' options permitted.\n",
					program_name);
				exit(1);
			}
			action_type = EMT_DELEROUTE;
			break;
		case 'e':
			if(said_opt) {
				fprintf(stderr, "%s: Error, EDST parameter redefined:%s, already defined in SA:%s\n",
					program_name, optarg, said_opt);
				exit (1);
			}				
			if(edst_opt) {
				fprintf(stderr, "%s: Error, EDST parameter redefined:%s, already defined as:%s\n",
					program_name, optarg, edst_opt);
				exit (1);
			}				
			if((error_s = ttoaddr(optarg, 0, said_af, &said.dst)) != 0) {
				if(error_s) {
					fprintf(stderr, "%s: Error, %s converting --edst argument:%s\n",
						program_name, error_s, optarg);
					exit (1);
				}
			}
			edst_opt = optarg;
			break;
		case 'h':
		case '?':
			usage(program_name);
			exit(1);
		case 's':
			if(said_opt) {
				fprintf(stderr, "%s: Error, SPI parameter redefined:%s, already defined in SA:%s\n",
					program_name, optarg, said_opt);
				exit (1);
			}				
			if(spi_opt) {
				fprintf(stderr, "%s: Error, SPI parameter redefined:%s, already defined as:%s\n",
					program_name, optarg, spi_opt);
				exit (1);
			}				
			said.spi = htonl(strtoul(optarg, &endptr, 0));
			if(!(endptr == optarg + strlen(optarg))) {
				fprintf(stderr, "%s: Invalid character in SPI parameter: %s\n",
					program_name, optarg);
				exit (1);
			}
			if(ntohl(said.spi) < 0x100) {
				fprintf(stderr, "%s: Illegal reserved spi: %s => 0x%x Must be larger than 0x100.\n",
					program_name, optarg, ntohl(said.spi));
				exit(1);
			}
			spi_opt = optarg;
			break;
		case 'p':
			if(said_opt) {
				fprintf(stderr, "%s: Error, PROTO parameter redefined:%s, already defined in SA:%s\n",
					program_name, optarg, said_opt);
				exit (1);
			}				
			if(proto_opt) {
				fprintf(stderr, "%s: Error, PROTO parameter redefined:%s, already defined as:%s\n",
					program_name, optarg, proto_opt);
				exit (1);
			}
#if 0
			if(said.proto) {
				fprintf(stderr, "%s: Warning, PROTO parameter redefined:%s\n",
					program_name, optarg);
				exit (1);
			}
#endif
			if(!strcmp(optarg, "ah"))
				said.proto = SA_AH;
			if(!strcmp(optarg, "esp"))
				said.proto = SA_ESP;
			if(!strcmp(optarg, "tun"))
				said.proto = SA_IPIP;
			if(!strcmp(optarg, "comp"))
				said.proto = SA_COMP;
			if(said.proto == 0) {
				fprintf(stderr, "%s: Invalid PROTO parameter: %s\n",
					program_name, optarg);
				exit (1);
			}
			proto_opt = optarg;
			break;
		case 'I':
			if(said_opt) {
				fprintf(stderr, "%s: Error, SAID parameter redefined:%s, already defined in SA:%s\n",
					program_name, optarg, said_opt);
				exit (1);
			}				
			if(proto_opt) {
				fprintf(stderr, "%s: Error, PROTO parameter redefined in SA:%s, already defined as:%s\n",
					program_name, optarg, proto_opt);
				exit (1);
			}
			if(edst_opt) {
				fprintf(stderr, "%s: Error, EDST parameter redefined in SA:%s, already defined as:%s\n",
					program_name, optarg, edst_opt);
				exit (1);
			}
			if(spi_opt) {
				fprintf(stderr, "%s: Error, SPI parameter redefined in SA:%s, already defined as:%s\n",
					program_name, optarg, spi_opt);
				exit (1);
			}
			if(said_af_opt) {
				fprintf(stderr, "%s: Error, address family parameter redefined in SA:%s, already defined as:%s\n",
					program_name, optarg, said_af_opt);
				exit (1);
			}
			if((error_s = ttosa(optarg, 0, &said)) != NULL) {
				fprintf(stderr, "%s: Error, %s converting --sa argument:%s\n",
					program_name, error_s, optarg);
				exit (1);
			} else if(ntohl(said.spi) < 0x100){
				fprintf(stderr, "%s: Illegal reserved spi: %s => 0x%x Must be larger than or equal to 0x100.\n",
					program_name, optarg, said.spi);
				exit(1);
			}
			said_af = addrtypeof(&said.dst);
			said_opt = optarg;
			break;
		case 'v':
			fprintf(stdout, "%s, %s\n", program_name, eroute_c_version);
			exit(1);
		case 'D':
			if(dst_opt) {
				fprintf(stderr, "%s: Error, DDST parameter redefined:%s, already defined as:%s\n",
					program_name, optarg, dst_opt);
				exit (1);
			}				
			if (ttosubnet(optarg, 0, eroute_af, &d_subnet)) {
				fprintf(stderr, "%s: Invalid formation of destination network/mask: %s\n",
					program_name, optarg);
				exit (1);
			}
			dst_opt = optarg;
			break;
		case 'S':
			if(src_opt) {
				fprintf(stderr, "%s: Error, SDST parameter redefined:%s, already defined as:%s\n",
					program_name, optarg, src_opt);
				exit (1);
			}				
			if (ttosubnet(optarg, 0, eroute_af, &s_subnet)) {
				fprintf(stderr, "%s: Invalid formation of source network/mask: %s\n",
					program_name, optarg);
				exit (1);
			}
			src_opt = optarg;
			break;
		case 'l':
			program_name = malloc(strlen(argv[0])
					      + 10 /* update this when changing the sprintf() */
					      + strlen(optarg));
			sprintf(program_name, "%s --label %s",
				argv[0],
				optarg);
			argcount -= 2;
			break;
		case 'i': /* specifies the address family of the SAID, stored in said_af */
			if(said_af_opt) {
				fprintf(stderr, "%s: Error, address family of SAID redefined:%s, already defined as:%s\n",
					program_name, optarg, said_af_opt);
				exit (1);
			}				
			if(!strcmp(optarg, "inet"))
				said_af = AF_INET;
			if(!strcmp(optarg, "inet6"))
				said_af = AF_INET6;
			if(said_af == 0) {
				fprintf(stderr, "%s: Invalid address family parameter for SAID: %s\n",
					program_name, optarg);
				exit (1);
			}
			said_af_opt = optarg;
			break;
		case 'f': /* specifies the address family of the eroute, stored in eroute_af */
			if(eroute_af_opt) {
				fprintf(stderr, "%s: Error, address family of eroute redefined:%s, already defined as:%s\n",
					program_name, optarg, eroute_af_opt);
				exit (1);
			}				
			if(!strcmp(optarg, "inet"))
				eroute_af = AF_INET;
			if(!strcmp(optarg, "inet6"))
				eroute_af = AF_INET6;
			if(eroute_af == 0) {
				fprintf(stderr, "%s: Invalid address family parameter for eroute: %s\n",
					program_name, optarg);
				exit (1);
			}
			eroute_af_opt = optarg;
			break;
		case '+': /* optionsfrom */
			optionsfrom(optarg, &argc, &argv, optind, stderr);
			/* no return on error */
			break;
		default:
		}
		previous = c;
	}

	if(debug) {
		fprintf(stdout, "%s: DEBUG: argc=%d\n", program_name, argc);
	}
	
	if(argcount == 1) {
		system("cat /proc/net/ipsec_eroute");
		exit(0);
	}

	/* Sanity checks */

	if(debug) {
		fprintf(stdout, "%s: DEBUG: action_type=%d\n", program_name, action_type);
	}

	switch(action_type) {
	case EMT_SETEROUTE:
	case EMT_RPLACEROUTE:
		if(!(said_af_opt && edst_opt && spi_opt && proto_opt) && !(said_opt)) {
			fprintf(stderr, "%s: add option must have SA specified.\n",
				program_name);
			exit(1);
		}
	case EMT_DELEROUTE:
		if(!src_opt) {
			fprintf(stderr, "%s: Error -- %s option '--src' is required.\n",
				program_name, (action_type == EMT_SETEROUTE) ? "add" : "del");
			exit(1);
		}
		if(!dst_opt) {
			fprintf(stderr, "%s: Error -- %s option '--dst' is required.\n",
				program_name, (action_type == EMT_SETEROUTE) ? "add" : "del");
			exit(1);
		}
	case EMT_CLREROUTE:
		break;
	default:
		fprintf(stderr, "%s: exactly one of '--add', '--replace', '--del' or '--clear' options must be specified.\n"
			"Try %s --help' for usage information.\n",
			program_name, program_name);
		exit(1);
	}

	if((pfkey_sock = socket(PF_KEY, SOCK_RAW, PF_KEY_V2) ) < 0) {
		fprintf(stderr, "%s: Trouble openning PF_KEY family socket with error: ",
			program_name);
		switch(errno) {
		case ENOENT:
			fprintf(stderr, "device does not exist.  See FreeS/WAN installation procedure.\n");
			break;
		case EACCES:
			fprintf(stderr, "access denied.  ");
			if(getuid() == 0) {
				fprintf(stderr, "Check permissions.  Should be 600.\n");
			} else {
				fprintf(stderr, "You must be root to open this file.\n");
			}
			break;
		case EUNATCH:
			fprintf(stderr, "KLIPS not loaded.\n");
			break;
		case ENODEV:
			fprintf(stderr, "KLIPS not loaded or enabled.\n");
			break;
		case EBUSY:
			fprintf(stderr, "KLIPS is busy.  Most likely a serious internal error occured in a previous command.  Please report as much detail as possible to development team.\n");
			break;
		case EINVAL:
			fprintf(stderr, "Invalid argument, KLIPS not loaded or check kernel log messages for specifics.\n");
			break;
		case ENOBUFS:
		case ENOMEM:
		case ENFILE: