ipsopt.c revision 80486
122514Sdarrenr/*
253024Sguido * Copyright (C) 1995-1998 by Darren Reed.
322514Sdarrenr *
480486Sdarrenr * See the IPFILTER.LICENCE file for details on licencing.
522514Sdarrenr */
622514Sdarrenr#include <stdio.h>
722514Sdarrenr#include <string.h>
831183Speter#include <stdlib.h>
922514Sdarrenr#include <sys/types.h>
1022514Sdarrenr#include <sys/time.h>
1122514Sdarrenr#include <sys/socket.h>
1222514Sdarrenr#include <netinet/in.h>
1322514Sdarrenr#include <netinet/in_systm.h>
1422514Sdarrenr#include <netinet/ip.h>
1531183Speter#ifndef	linux
1631183Speter#include <netinet/ip_var.h>
1731183Speter#endif
1831183Speter#include <netinet/tcp.h>
1931183Speter#include <arpa/inet.h>
2031183Speter#include "ipsend.h"
2122514Sdarrenr
2280486Sdarrenr#if !defined(lint)
2380486Sdarrenrstatic const char sccsid[] = "@(#)ipsopt.c	1.2 1/11/96 (C)1995 Darren Reed";
2480486Sdarrenrstatic const char rcsid[] = "@(#)$Id: ipsopt.c,v 2.1.4.2 2001/07/15 22:00:14 darrenr Exp $";
2524583Sdarrenr#endif
2624583Sdarrenr
2724583Sdarrenr
2822514Sdarrenrstruct ipopt_names ionames[] = {
2922514Sdarrenr	{ IPOPT_EOL,	0x01,	1, "eol" },
3022514Sdarrenr	{ IPOPT_NOP,	0x02,	1, "nop" },
3131183Speter	{ IPOPT_RR,	0x04,	3, "rr" },	/* 1 route */
3222514Sdarrenr	{ IPOPT_TS,	0x08,	8, "ts" },	/* 1 TS */
3322514Sdarrenr	{ IPOPT_SECURITY, 0x08,	11, "sec-level" },
3422514Sdarrenr	{ IPOPT_LSRR,	0x10,	7, "lsrr" },	/* 1 route */
3522514Sdarrenr	{ IPOPT_SATID,	0x20,	4, "satid" },
3622514Sdarrenr	{ IPOPT_SSRR,	0x40,	7, "ssrr" },	/* 1 route */
3722514Sdarrenr	{ 0, 0, 0, NULL }	/* must be last */
3822514Sdarrenr};
3922514Sdarrenr
4022514Sdarrenrstruct	ipopt_names secnames[] = {
4122514Sdarrenr	{ IPOPT_SECUR_UNCLASS,	0x0100,	0, "unclass" },
4222514Sdarrenr	{ IPOPT_SECUR_CONFID,	0x0200,	0, "confid" },
4322514Sdarrenr	{ IPOPT_SECUR_EFTO,	0x0400,	0, "efto" },
4422514Sdarrenr	{ IPOPT_SECUR_MMMM,	0x0800,	0, "mmmm" },
4522514Sdarrenr	{ IPOPT_SECUR_RESTR,	0x1000,	0, "restr" },
4622514Sdarrenr	{ IPOPT_SECUR_SECRET,	0x2000,	0, "secret" },
4722514Sdarrenr	{ IPOPT_SECUR_TOPSECRET, 0x4000,0, "topsecret" },
4822514Sdarrenr	{ 0, 0, 0, NULL }	/* must be last */
4922514Sdarrenr};
5022514Sdarrenr
5122514Sdarrenr
5222514Sdarrenru_short seclevel(slevel)
5322514Sdarrenrchar *slevel;
5422514Sdarrenr{
5522514Sdarrenr	struct ipopt_names *so;
5622514Sdarrenr
5722514Sdarrenr	for (so = secnames; so->on_name; so++)
5822514Sdarrenr		if (!strcasecmp(slevel, so->on_name))
5922514Sdarrenr			break;
6022514Sdarrenr
6122514Sdarrenr	if (!so->on_name) {
6222514Sdarrenr		fprintf(stderr, "no such security level: %s\n", slevel);
6322514Sdarrenr		return 0;
6422514Sdarrenr	}
6522514Sdarrenr	return so->on_value;
6622514Sdarrenr}
6722514Sdarrenr
6822514Sdarrenr
6931183Speterint addipopt(op, io, len, class)
7031183Speterchar *op;
7131183Speterstruct ipopt_names *io;
7231183Speterint len;
7331183Speterchar *class;
7431183Speter{
7531183Speter	struct in_addr ipadr;
7631183Speter	int olen = len, srr = 0;
7731183Speter	u_short val;
7831183Speter	u_char lvl;
7931183Speter	char *s = op, *t;
8031183Speter
8131183Speter	if ((len + io->on_siz) > 48) {
8231183Speter		fprintf(stderr, "options too long\n");
8331183Speter		return 0;
8431183Speter	}
8531183Speter	len += io->on_siz;
8631183Speter	*op++ = io->on_value;
8731183Speter	if (io->on_siz > 1) {
8831183Speter		/*
8931183Speter		 * Allow option to specify RR buffer length in bytes.
9031183Speter		 */
9131183Speter		if (io->on_value == IPOPT_RR) {
9231183Speter			val = (class && *class) ? atoi(class) : 4;
9331183Speter			*op++ = val + io->on_siz;
9431183Speter			len += val;
9531183Speter		} else
9631183Speter			*op++ = io->on_siz;
9731183Speter		*op++ = IPOPT_MINOFF;
9831183Speter
9931183Speter		while (class && *class) {
10031183Speter			t = NULL;
10131183Speter			switch (io->on_value)
10231183Speter			{
10331183Speter			case IPOPT_SECURITY :
10431183Speter				lvl = seclevel(class);
10531183Speter				*(op - 1) = lvl;
10631183Speter				break;
10731183Speter			case IPOPT_LSRR :
10831183Speter			case IPOPT_SSRR :
10931183Speter				if ((t = strchr(class, ',')))
11031183Speter					*t = '\0';
11131183Speter				ipadr.s_addr = inet_addr(class);
11231183Speter				srr++;
11331183Speter				bcopy((char *)&ipadr, op, sizeof(ipadr));
11431183Speter				op += sizeof(ipadr);
11531183Speter				break;
11631183Speter			case IPOPT_SATID :
11731183Speter				val = atoi(class);
11831183Speter				bcopy((char *)&val, op, 2);
11931183Speter				break;
12031183Speter			}
12131183Speter
12231183Speter			if (t)
12331183Speter				*t++ = ',';
12431183Speter			class = t;
12531183Speter		}
12631183Speter		if (srr)
12731183Speter			s[IPOPT_OLEN] = IPOPT_MINOFF - 1 + 4 * srr;
12831183Speter		if (io->on_value == IPOPT_RR)
12931183Speter			op += val;
13031183Speter		else
13131183Speter			op += io->on_siz - 3;
13231183Speter	}
13331183Speter	return len - olen;
13431183Speter}
13531183Speter
13631183Speter
13731183Speteru_32_t buildopts(cp, op, len)
13822514Sdarrenrchar *cp, *op;
13931183Speterint len;
14022514Sdarrenr{
14122514Sdarrenr	struct ipopt_names *io;
14231183Speter	u_32_t msk = 0;
14322514Sdarrenr	char *s, *t;
14431183Speter	int inc, lastop = -1;
14522514Sdarrenr
14622514Sdarrenr	for (s = strtok(cp, ","); s; s = strtok(NULL, ",")) {
14722514Sdarrenr		if ((t = strchr(s, '=')))
14822514Sdarrenr			*t++ = '\0';
14922514Sdarrenr		for (io = ionames; io->on_name; io++) {
15022514Sdarrenr			if (strcasecmp(s, io->on_name) || (msk & io->on_bit))
15122514Sdarrenr				continue;
15231183Speter			lastop = io->on_value;
15331183Speter			if ((inc = addipopt(op, io, len, t))) {
15431183Speter				op += inc;
15531183Speter				len += inc;
15622514Sdarrenr			}
15722514Sdarrenr			msk |= io->on_bit;
15822514Sdarrenr			break;
15922514Sdarrenr		}
16022514Sdarrenr		if (!io->on_name) {
16122514Sdarrenr			fprintf(stderr, "unknown IP option name %s\n", s);
16222514Sdarrenr			return 0;
16322514Sdarrenr		}
16422514Sdarrenr	}
16531183Speter
16631183Speter	if (len & 3) {
16731183Speter		while (len & 3) {
16831183Speter			*op++ = ((len & 3) == 3) ? IPOPT_EOL : IPOPT_NOP;
16931183Speter			len++;
17031183Speter		}
17131183Speter	} else {
17231183Speter		if (lastop != IPOPT_EOL) {
17331183Speter			if (lastop == IPOPT_NOP)
17431183Speter				*(op - 1) = IPOPT_EOL;
17531183Speter			else {
17631183Speter				*op++ = IPOPT_NOP;
17731183Speter				*op++ = IPOPT_NOP;
17831183Speter				*op++ = IPOPT_NOP;
17931183Speter				*op = IPOPT_EOL;
18031183Speter				len += 4;
18131183Speter			}
18231183Speter		}
18331183Speter	}
18422514Sdarrenr	return len;
18522514Sdarrenr}
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