xref: /freebsd/contrib/tcpdump/print-ip6opts.c (revision e796cc77c586c2955b2f3940dbf4991b31e8d289)
1 /*
2  * Copyright (C) 1998 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /* \summary: IPv6 header option printer */
31 
32 #ifdef HAVE_CONFIG_H
33 #include "config.h"
34 #endif
35 
36 #include <netdissect-stdinc.h>
37 
38 #include "netdissect.h"
39 #include "addrtoname.h"
40 #include "extract.h"
41 
42 #include "ip6.h"
43 
44 static void
45 ip6_sopt_print(netdissect_options *ndo, const u_char *bp, int len)
46 {
47     int i;
48     int optlen;
49 
50     for (i = 0; i < len; i += optlen) {
51 	if (bp[i] == IP6OPT_PAD1)
52 	    optlen = 1;
53 	else {
54 	    if (i + 1 < len)
55 		optlen = bp[i + 1] + 2;
56 	    else
57 		goto trunc;
58 	}
59 	if (i + optlen > len)
60 	    goto trunc;
61 
62 	switch (bp[i]) {
63 	case IP6OPT_PAD1:
64             ND_PRINT((ndo, ", pad1"));
65 	    break;
66 	case IP6OPT_PADN:
67 	    if (len - i < IP6OPT_MINLEN) {
68 		ND_PRINT((ndo, ", padn: trunc"));
69 		goto trunc;
70 	    }
71             ND_PRINT((ndo, ", padn"));
72 	    break;
73 	default:
74 	    if (len - i < IP6OPT_MINLEN) {
75 		ND_PRINT((ndo, ", sopt_type %d: trunc)", bp[i]));
76 		goto trunc;
77 	    }
78 	    ND_PRINT((ndo, ", sopt_type 0x%02x: len=%d", bp[i], bp[i + 1]));
79 	    break;
80 	}
81     }
82     return;
83 
84 trunc:
85     ND_PRINT((ndo, "[trunc] "));
86 }
87 
88 static void
89 ip6_opt_print(netdissect_options *ndo, const u_char *bp, int len)
90 {
91     int i;
92     int optlen = 0;
93 
94     if (len == 0)
95         return;
96     for (i = 0; i < len; i += optlen) {
97 	if (bp[i] == IP6OPT_PAD1)
98 	    optlen = 1;
99 	else {
100 	    if (i + 1 < len)
101 		optlen = bp[i + 1] + 2;
102 	    else
103 		goto trunc;
104 	}
105 	if (i + optlen > len)
106 	    goto trunc;
107 
108 	switch (bp[i]) {
109 	case IP6OPT_PAD1:
110             ND_PRINT((ndo, "(pad1)"));
111 	    break;
112 	case IP6OPT_PADN:
113 	    if (len - i < IP6OPT_MINLEN) {
114 		ND_PRINT((ndo, "(padn: trunc)"));
115 		goto trunc;
116 	    }
117             ND_PRINT((ndo, "(padn)"));
118 	    break;
119 	case IP6OPT_ROUTER_ALERT:
120 	    if (len - i < IP6OPT_RTALERT_LEN) {
121 		ND_PRINT((ndo, "(rtalert: trunc)"));
122 		goto trunc;
123 	    }
124 	    if (bp[i + 1] != IP6OPT_RTALERT_LEN - 2) {
125 		ND_PRINT((ndo, "(rtalert: invalid len %d)", bp[i + 1]));
126 		goto trunc;
127 	    }
128 	    ND_PRINT((ndo, "(rtalert: 0x%04x) ", EXTRACT_16BITS(&bp[i + 2])));
129 	    break;
130 	case IP6OPT_JUMBO:
131 	    if (len - i < IP6OPT_JUMBO_LEN) {
132 		ND_PRINT((ndo, "(jumbo: trunc)"));
133 		goto trunc;
134 	    }
135 	    if (bp[i + 1] != IP6OPT_JUMBO_LEN - 2) {
136 		ND_PRINT((ndo, "(jumbo: invalid len %d)", bp[i + 1]));
137 		goto trunc;
138 	    }
139 	    ND_PRINT((ndo, "(jumbo: %u) ", EXTRACT_32BITS(&bp[i + 2])));
140 	    break;
141         case IP6OPT_HOME_ADDRESS:
142 	    if (len - i < IP6OPT_HOMEADDR_MINLEN) {
143 		ND_PRINT((ndo, "(homeaddr: trunc)"));
144 		goto trunc;
145 	    }
146 	    if (bp[i + 1] < IP6OPT_HOMEADDR_MINLEN - 2) {
147 		ND_PRINT((ndo, "(homeaddr: invalid len %d)", bp[i + 1]));
148 		goto trunc;
149 	    }
150 	    ND_PRINT((ndo, "(homeaddr: %s", ip6addr_string(ndo, &bp[i + 2])));
151             if (bp[i + 1] > IP6OPT_HOMEADDR_MINLEN - 2) {
152 		ip6_sopt_print(ndo, &bp[i + IP6OPT_HOMEADDR_MINLEN],
153 		    (optlen - IP6OPT_HOMEADDR_MINLEN));
154 	    }
155             ND_PRINT((ndo, ")"));
156 	    break;
157 	default:
158 	    if (len - i < IP6OPT_MINLEN) {
159 		ND_PRINT((ndo, "(type %d: trunc)", bp[i]));
160 		goto trunc;
161 	    }
162 	    ND_PRINT((ndo, "(opt_type 0x%02x: len=%d)", bp[i], bp[i + 1]));
163 	    break;
164 	}
165     }
166     ND_PRINT((ndo, " "));
167     return;
168 
169 trunc:
170     ND_PRINT((ndo, "[trunc] "));
171 }
172 
173 int
174 hbhopt_print(netdissect_options *ndo, register const u_char *bp)
175 {
176     const struct ip6_hbh *dp = (const struct ip6_hbh *)bp;
177     int hbhlen = 0;
178 
179     ND_TCHECK(dp->ip6h_len);
180     hbhlen = (int)((dp->ip6h_len + 1) << 3);
181     ND_TCHECK2(*dp, hbhlen);
182     ND_PRINT((ndo, "HBH "));
183     if (ndo->ndo_vflag)
184 	ip6_opt_print(ndo, (const u_char *)dp + sizeof(*dp), hbhlen - sizeof(*dp));
185 
186     return(hbhlen);
187 
188   trunc:
189     ND_PRINT((ndo, "[|HBH]"));
190     return(-1);
191 }
192 
193 int
194 dstopt_print(netdissect_options *ndo, register const u_char *bp)
195 {
196     const struct ip6_dest *dp = (const struct ip6_dest *)bp;
197     int dstoptlen = 0;
198 
199     ND_TCHECK(dp->ip6d_len);
200     dstoptlen = (int)((dp->ip6d_len + 1) << 3);
201     ND_TCHECK2(*dp, dstoptlen);
202     ND_PRINT((ndo, "DSTOPT "));
203     if (ndo->ndo_vflag) {
204 	ip6_opt_print(ndo, (const u_char *)dp + sizeof(*dp),
205 	    dstoptlen - sizeof(*dp));
206     }
207 
208     return(dstoptlen);
209 
210   trunc:
211     ND_PRINT((ndo, "[|DSTOPT]"));
212     return(-1);
213 }
214