1 /* Shared library add-on to ip6tables to add Fragmentation header support. */
9 #include <linux/netfilter_ipv6/ip6t_frag.h>
11 /* Function which prints out usage message. */
17 " --fragid [!] id[:id] match the id (range)\n"
18 " --fraglen [!] length total length of this header\n"
19 " --fragres check the reserved filed, too\n"
20 " --fragfirst matches on the first fragment\n"
21 " [--fragmore|--fraglast] there are more fragments or this\n"
26 static struct option opts[] = {
27 { .name = "fragid", .has_arg = 1, .flag = 0, .val = '1' },
28 { .name = "fraglen", .has_arg = 1, .flag = 0, .val = '2' },
29 { .name = "fragres", .has_arg = 0, .flag = 0, .val = '3' },
30 { .name = "fragfirst", .has_arg = 0, .flag = 0, .val = '4' },
31 { .name = "fragmore", .has_arg = 0, .flag = 0, .val = '5' },
32 { .name = "fraglast", .has_arg = 0, .flag = 0, .val = '6' },
37 parse_frag_id(const char *idstr, const char *typestr)
42 id = strtoul(idstr, &ep, 0);
45 exit_error(PARAMETER_PROBLEM,
46 "FRAG no valid digits in %s `%s'", typestr, idstr);
48 if ( id == ULONG_MAX && errno == ERANGE ) {
49 exit_error(PARAMETER_PROBLEM,
50 "%s `%s' specified too big: would overflow",
53 if ( *idstr != '\0' && *ep != '\0' ) {
54 exit_error(PARAMETER_PROBLEM,
55 "FRAG error parsing %s `%s'", typestr, idstr);
57 return (u_int32_t) id;
61 parse_frag_ids(const char *idstring, u_int32_t *ids)
66 buffer = strdup(idstring);
67 if ((cp = strchr(buffer, ':')) == NULL)
68 ids[0] = ids[1] = parse_frag_id(buffer,"id");
73 ids[0] = buffer[0] ? parse_frag_id(buffer,"id") : 0;
74 ids[1] = cp[0] ? parse_frag_id(cp,"id") : 0xFFFFFFFF;
79 /* Initialize the match. */
81 init(struct ip6t_entry_match *m, unsigned int *nfcache)
83 struct ip6t_frag *fraginfo = (struct ip6t_frag *)m->data;
85 fraginfo->ids[0] = 0x0L;
86 fraginfo->ids[1] = 0xFFFFFFFF;
89 fraginfo->invflags = 0;
92 /* Function which parses command options; returns true if it
95 parse(int c, char **argv, int invert, unsigned int *flags,
96 const struct ip6t_entry *entry,
97 unsigned int *nfcache,
98 struct ip6t_entry_match **match)
100 struct ip6t_frag *fraginfo = (struct ip6t_frag *)(*match)->data;
104 if (*flags & IP6T_FRAG_IDS)
105 exit_error(PARAMETER_PROBLEM,
106 "Only one `--fragid' allowed");
107 check_inverse(optarg, &invert, &optind, 0);
108 parse_frag_ids(argv[optind-1], fraginfo->ids);
110 fraginfo->invflags |= IP6T_FRAG_INV_IDS;
111 fraginfo->flags |= IP6T_FRAG_IDS;
112 *flags |= IP6T_FRAG_IDS;
115 if (*flags & IP6T_FRAG_LEN)
116 exit_error(PARAMETER_PROBLEM,
117 "Only one `--fraglen' allowed");
118 check_inverse(optarg, &invert, &optind, 0);
119 fraginfo->hdrlen = parse_frag_id(argv[optind-1], "length");
121 fraginfo->invflags |= IP6T_FRAG_INV_LEN;
122 fraginfo->flags |= IP6T_FRAG_LEN;
123 *flags |= IP6T_FRAG_LEN;
126 if (*flags & IP6T_FRAG_RES)
127 exit_error(PARAMETER_PROBLEM,
128 "Only one `--fragres' allowed");
129 fraginfo->flags |= IP6T_FRAG_RES;
130 *flags |= IP6T_FRAG_RES;
133 if (*flags & IP6T_FRAG_FST)
134 exit_error(PARAMETER_PROBLEM,
135 "Only one `--fragfirst' allowed");
136 fraginfo->flags |= IP6T_FRAG_FST;
137 *flags |= IP6T_FRAG_FST;
140 if (*flags & (IP6T_FRAG_MF|IP6T_FRAG_NMF))
141 exit_error(PARAMETER_PROBLEM,
142 "Only one `--fragmore' or `--fraglast' allowed");
143 fraginfo->flags |= IP6T_FRAG_MF;
144 *flags |= IP6T_FRAG_MF;
147 if (*flags & (IP6T_FRAG_MF|IP6T_FRAG_NMF))
148 exit_error(PARAMETER_PROBLEM,
149 "Only one `--fragmore' or `--fraglast' allowed");
150 fraginfo->flags |= IP6T_FRAG_NMF;
151 *flags |= IP6T_FRAG_NMF;
160 /* Final check; we don't care. */
162 final_check(unsigned int flags)
167 print_ids(const char *name, u_int32_t min, u_int32_t max,
170 const char *inv = invert ? "!" : "";
172 if (min != 0 || max != 0xFFFFFFFF || invert) {
175 printf(":%s%u ", inv, min);
177 printf("s:%s%u:%u ", inv, min, max);
181 /* Prints out the union ip6t_matchinfo. */
183 print(const struct ip6t_ip6 *ip,
184 const struct ip6t_entry_match *match, int numeric)
186 const struct ip6t_frag *frag = (struct ip6t_frag *)match->data;
189 print_ids("id", frag->ids[0], frag->ids[1],
190 frag->invflags & IP6T_FRAG_INV_IDS);
192 if (frag->flags & IP6T_FRAG_LEN) {
193 printf("length:%s%u ",
194 frag->invflags & IP6T_FRAG_INV_LEN ? "!" : "",
198 if (frag->flags & IP6T_FRAG_RES)
201 if (frag->flags & IP6T_FRAG_FST)
204 if (frag->flags & IP6T_FRAG_MF)
207 if (frag->flags & IP6T_FRAG_NMF)
210 if (frag->invflags & ~IP6T_FRAG_INV_MASK)
211 printf("Unknown invflags: 0x%X ",
212 frag->invflags & ~IP6T_FRAG_INV_MASK);
215 /* Saves the union ip6t_matchinfo in parsable form to stdout. */
216 static void save(const struct ip6t_ip6 *ip, const struct ip6t_entry_match *match)
218 const struct ip6t_frag *fraginfo = (struct ip6t_frag *)match->data;
220 if (!(fraginfo->ids[0] == 0
221 && fraginfo->ids[1] == 0xFFFFFFFF)) {
222 printf("--fragid %s",
223 (fraginfo->invflags & IP6T_FRAG_INV_IDS) ? "! " : "");
234 if (fraginfo->flags & IP6T_FRAG_LEN) {
235 printf("--fraglen %s%u ",
236 (fraginfo->invflags & IP6T_FRAG_INV_LEN) ? "! " : "",
240 if (fraginfo->flags & IP6T_FRAG_RES)
241 printf("--fragres ");
243 if (fraginfo->flags & IP6T_FRAG_FST)
244 printf("--fragfirst ");
246 if (fraginfo->flags & IP6T_FRAG_MF)
247 printf("--fragmore ");
249 if (fraginfo->flags & IP6T_FRAG_NMF)
250 printf("--fraglast ");
254 struct ip6tables_match frag = {
256 .version = IPTABLES_VERSION,
257 .size = IP6T_ALIGN(sizeof(struct ip6t_frag)),
258 .userspacesize = IP6T_ALIGN(sizeof(struct ip6t_frag)),
262 .final_check = &final_check,
271 register_match6(&frag);