ipsopt.c revision 53024 
1/*
2 * Copyright (C) 1995-1998 by Darren Reed.
3 *
4 * Redistribution and use in source and binary forms are permitted
5 * provided that this notice is preserved and due credit is given
6 * to the original author and the contributors.
7 */
8#if !defined(lint)
9static const char sccsid[] = "@(#)ipsopt.c	1.2 1/11/96 (C)1995 Darren Reed";
10static const char rcsid[] = "@(#)$Id: ipsopt.c,v 2.1 1999/08/04 17:31:07 darrenr Exp $";
11#endif
12#include <stdio.h>
13#include <string.h>
14#include <stdlib.h>
15#include <sys/types.h>
16#include <sys/time.h>
17#include <sys/socket.h>
18#include <netinet/in.h>
19#include <netinet/in_systm.h>
20#include <netinet/ip.h>
21#ifndef	linux
22#include <netinet/ip_var.h>
23#endif
24#include <netinet/tcp.h>
25#include <arpa/inet.h>
26#include "ipsend.h"
27
28
29#ifndef	__P
30# ifdef	__STDC__
31#  define	__P(x)	x
32# else
33#  define	__P(x)	()
34# endif
35#endif
36
37
38struct ipopt_names ionames[] = {
39	{ IPOPT_EOL,	0x01,	1, "eol" },
40	{ IPOPT_NOP,	0x02,	1, "nop" },
41	{ IPOPT_RR,	0x04,	3, "rr" },	/* 1 route */
42	{ IPOPT_TS,	0x08,	8, "ts" },	/* 1 TS */
43	{ IPOPT_SECURITY, 0x08,	11, "sec-level" },
44	{ IPOPT_LSRR,	0x10,	7, "lsrr" },	/* 1 route */
45	{ IPOPT_SATID,	0x20,	4, "satid" },
46	{ IPOPT_SSRR,	0x40,	7, "ssrr" },	/* 1 route */
47	{ 0, 0, 0, NULL }	/* must be last */
48};
49
50struct	ipopt_names secnames[] = {
51	{ IPOPT_SECUR_UNCLASS,	0x0100,	0, "unclass" },
52	{ IPOPT_SECUR_CONFID,	0x0200,	0, "confid" },
53	{ IPOPT_SECUR_EFTO,	0x0400,	0, "efto" },
54	{ IPOPT_SECUR_MMMM,	0x0800,	0, "mmmm" },
55	{ IPOPT_SECUR_RESTR,	0x1000,	0, "restr" },
56	{ IPOPT_SECUR_SECRET,	0x2000,	0, "secret" },
57	{ IPOPT_SECUR_TOPSECRET, 0x4000,0, "topsecret" },
58	{ 0, 0, 0, NULL }	/* must be last */
59};
60
61
62u_short seclevel(slevel)
63char *slevel;
64{
65	struct ipopt_names *so;
66
67	for (so = secnames; so->on_name; so++)
68		if (!strcasecmp(slevel, so->on_name))
69			break;
70
71	if (!so->on_name) {
72		fprintf(stderr, "no such security level: %s\n", slevel);
73		return 0;
74	}
75	return so->on_value;
76}
77
78
79int addipopt(op, io, len, class)
80char *op;
81struct ipopt_names *io;
82int len;
83char *class;
84{
85	struct in_addr ipadr;
86	int olen = len, srr = 0;
87	u_short val;
88	u_char lvl;
89	char *s = op, *t;
90
91	if ((len + io->on_siz) > 48) {
92		fprintf(stderr, "options too long\n");
93		return 0;
94	}
95	len += io->on_siz;
96	*op++ = io->on_value;
97	if (io->on_siz > 1) {
98		/*
99		 * Allow option to specify RR buffer length in bytes.
100		 */
101		if (io->on_value == IPOPT_RR) {
102			val = (class && *class) ? atoi(class) : 4;
103			*op++ = val + io->on_siz;
104			len += val;
105		} else
106			*op++ = io->on_siz;
107		*op++ = IPOPT_MINOFF;
108
109		while (class && *class) {
110			t = NULL;
111			switch (io->on_value)
112			{
113			case IPOPT_SECURITY :
114				lvl = seclevel(class);
115				*(op - 1) = lvl;
116				break;
117			case IPOPT_LSRR :
118			case IPOPT_SSRR :
119				if ((t = strchr(class, ',')))
120					*t = '\0';
121				ipadr.s_addr = inet_addr(class);
122				srr++;
123				bcopy((char *)&ipadr, op, sizeof(ipadr));
124				op += sizeof(ipadr);
125				break;
126			case IPOPT_SATID :
127				val = atoi(class);
128				bcopy((char *)&val, op, 2);
129				break;
130			}
131
132			if (t)
133				*t++ = ',';
134			class = t;
135		}
136		if (srr)
137			s[IPOPT_OLEN] = IPOPT_MINOFF - 1 + 4 * srr;
138		if (io->on_value == IPOPT_RR)
139			op += val;
140		else
141			op += io->on_siz - 3;
142	}
143	return len - olen;
144}
145
146
147u_32_t buildopts(cp, op, len)
148char *cp, *op;
149int len;
150{
151	struct ipopt_names *io;
152	u_32_t msk = 0;
153	char *s, *t;
154	int inc, lastop = -1;
155
156	for (s = strtok(cp, ","); s; s = strtok(NULL, ",")) {
157		if ((t = strchr(s, '=')))
158			*t++ = '\0';
159		for (io = ionames; io->on_name; io++) {
160			if (strcasecmp(s, io->on_name) || (msk & io->on_bit))
161				continue;
162			lastop = io->on_value;
163			if ((inc = addipopt(op, io, len, t))) {
164				op += inc;
165				len += inc;
166			}
167			msk |= io->on_bit;
168			break;
169		}
170		if (!io->on_name) {
171			fprintf(stderr, "unknown IP option name %s\n", s);
172			return 0;
173		}
174	}
175
176	if (len & 3) {
177		while (len & 3) {
178			*op++ = ((len & 3) == 3) ? IPOPT_EOL : IPOPT_NOP;
179			len++;
180		}
181	} else {
182		if (lastop != IPOPT_EOL) {
183			if (lastop == IPOPT_NOP)
184				*(op - 1) = IPOPT_EOL;
185			else {
186				*op++ = IPOPT_NOP;
187				*op++ = IPOPT_NOP;
188				*op++ = IPOPT_NOP;
189				*op = IPOPT_EOL;
190				len += 4;
191			}
192		}
193	}
194	return len;
195}
196