Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0-only */
2 : /*
3 : * Copyright (c) 2022 Meta Platforms, Inc. and affiliates.
4 : */
5 :
6 : #include "dump.h"
7 :
8 : #include <linux/netfilter.h>
9 : #include <linux/netfilter/x_tables.h>
10 : #include <linux/netfilter_ipv4/ip_tables.h>
11 :
12 : #include <stdbool.h>
13 : #include <stdint.h>
14 : #include <stdio.h>
15 :
16 : #include "bpfilter/xlate/ipt/helpers.h"
17 : #include "core/dump.h"
18 : #include "core/helper.h"
19 :
20 : /**
21 : * Map each hook to its name as a string.
22 : */
23 : static const char *hook_name[] = {
24 : [NF_INET_PRE_ROUTING] = "PRE_ROUTING", [NF_INET_LOCAL_IN] = "LOCAL_IN",
25 : [NF_INET_FORWARD] = "FORWARD", [NF_INET_LOCAL_OUT] = "LOCAL_OUT",
26 : [NF_INET_POST_ROUTING] = "POST_ROUTING",
27 : };
28 :
29 : /**
30 : * Map each target to its name as a string.
31 : */
32 : static const char *target_name[] = {
33 : [NF_DROP] = "DROP", [NF_ACCEPT] = "ACCEPT", [NF_STOLEN] = "STOLEN",
34 : [NF_QUEUE] = "QUEUE", [NF_REPEAT] = "REPEAT", [NF_STOP] = "STOP",
35 : };
36 :
37 : /**
38 : * Dump content of @p ipt_counters structure.
39 : *
40 : * @param counters @p ipt_counters structure. Must be non-NULL.
41 : * @param prefix @p log_prefix structure.
42 : */
43 0 : static inline void ipt_dump_counters(const struct ipt_counters *counters,
44 : prefix_t *prefix)
45 : {
46 0 : bf_assert(counters && prefix);
47 :
48 0 : DUMP(prefix, "struct ipt_counters at %p", counters);
49 0 : }
50 :
51 : /**
52 : * Dump content of @p ipt_ip structure.
53 : *
54 : * @param ip @p ipt_ip structure. Must be non-NULL.
55 : * @param prefix @p log_prefix structure.
56 : */
57 0 : static void ipt_dump_ip(const struct ipt_ip *ip, prefix_t *prefix)
58 : {
59 0 : bf_assert(ip && prefix);
60 :
61 0 : DUMP(prefix, "struct ipt_ip at %p", ip);
62 :
63 0 : bf_dump_prefix_push(prefix);
64 0 : DUMP(prefix, "src: " IP4_FMT, IP4_SPLIT(ip->src));
65 0 : DUMP(prefix, "dst: " IP4_FMT, IP4_SPLIT(ip->dst));
66 0 : DUMP(prefix, "src_mask: " IP4_FMT, IP4_SPLIT(ip->smsk));
67 0 : DUMP(prefix, "dst_mask: " IP4_FMT, IP4_SPLIT(ip->dmsk));
68 0 : DUMP(prefix, "in_iface: %s", ip->iniface);
69 0 : DUMP(prefix, "out_iface: %s", ip->outiface);
70 0 : DUMP(prefix, "in_iface_mask: %s", ip->iniface_mask);
71 0 : DUMP(prefix, "out_iface_mask: %s", ip->outiface_mask);
72 0 : DUMP(prefix, "protocol: %d", ip->proto);
73 0 : DUMP(prefix, "flags: %d", ip->flags);
74 0 : DUMP(bf_dump_prefix_last(prefix), "invflags: %d", ip->invflags);
75 0 : bf_dump_prefix_pop(prefix);
76 0 : }
77 :
78 : /**
79 : * Dump content of @p ipt_entry_match structure.
80 : *
81 : * @param match @p ipt_entry_match structure. Must be non-NULL.
82 : * @param prefix @p log_prefix structure.
83 : */
84 0 : static void ipt_dump_match(const struct ipt_entry_match *match,
85 : prefix_t *prefix)
86 : {
87 0 : bf_assert(match && prefix);
88 :
89 0 : DUMP(prefix, "struct ipt_entry_match at %p", match);
90 :
91 0 : bf_dump_prefix_push(prefix);
92 0 : DUMP(prefix, "user:");
93 0 : DUMP(prefix, "match_size: %d", match->u.user.match_size);
94 0 : DUMP(prefix, "name: %s", match->u.user.name);
95 0 : DUMP(prefix, "revision: %d", match->u.user.revision);
96 0 : DUMP(prefix, "kernel:");
97 0 : DUMP(prefix, "match_size: %d", match->u.kernel.match_size);
98 0 : DUMP(prefix, "match at %p", match->u.kernel.match);
99 0 : DUMP(bf_dump_prefix_last(prefix), "match_size: %d", match->u.match_size);
100 0 : bf_dump_prefix_pop(prefix);
101 0 : }
102 :
103 : static inline int _bf_ipt_convert_verdict(int verdict)
104 : {
105 0 : return -verdict - 1;
106 : }
107 :
108 : /**
109 : * Dump content of @p ipt_entry_target structure.
110 : *
111 : * @param target @p ipt_entry_target structure. Must be non-NULL.
112 : * @param prefix @p log_prefix structure.
113 : */
114 0 : static void ipt_dump_target(const struct ipt_entry_target *target,
115 : prefix_t *prefix)
116 : {
117 : bool is_standard;
118 : struct ipt_standard_target *std_target = (void *)target;
119 :
120 0 : bf_assert(target && prefix);
121 :
122 : is_standard = bf_streq(target->u.user.name, "");
123 :
124 0 : DUMP(prefix, "struct ipt_entry_target at %p", target);
125 :
126 0 : bf_dump_prefix_push(prefix);
127 0 : DUMP(prefix, "user:");
128 :
129 0 : bf_dump_prefix_push(prefix);
130 0 : DUMP(prefix, "target_size: %d", target->u.user.target_size);
131 0 : DUMP(prefix, "name: '%s'", target->u.user.name);
132 0 : DUMP(bf_dump_prefix_last(prefix), "revision: %d", target->u.user.revision);
133 0 : bf_dump_prefix_pop(prefix);
134 :
135 0 : DUMP(prefix, "kernel:");
136 :
137 0 : bf_dump_prefix_push(prefix);
138 0 : DUMP(prefix, "target_size: %d", target->u.kernel.target_size);
139 0 : DUMP(bf_dump_prefix_last(prefix), "target: %p", target->u.kernel.target);
140 0 : bf_dump_prefix_pop(prefix);
141 :
142 0 : DUMP((is_standard ? prefix : bf_dump_prefix_last(prefix)),
143 : "target_size: %d", target->u.target_size);
144 0 : if (is_standard) {
145 0 : DUMP(bf_dump_prefix_last(prefix), "verdict: %s",
146 : target_name[_bf_ipt_convert_verdict(std_target->verdict)]);
147 : }
148 :
149 0 : bf_dump_prefix_pop(prefix);
150 0 : }
151 :
152 0 : void bf_ipt_dump_replace(struct ipt_replace *ipt, prefix_t *prefix)
153 : {
154 : int i;
155 : uint32_t offset;
156 : struct ipt_entry *first_rule;
157 : struct ipt_entry *last_rule;
158 :
159 0 : bf_assert(ipt && prefix);
160 :
161 0 : DUMP(prefix, "struct ipt_replace at %p", ipt);
162 :
163 0 : bf_dump_prefix_push(prefix);
164 :
165 0 : DUMP(prefix, "name: '%s'", ipt->name);
166 0 : DUMP(prefix, "valid_hooks: " BIN_FMT "", BIN_SPLIT(ipt->valid_hooks));
167 0 : DUMP(prefix, "num_entries: %d", ipt->num_entries);
168 0 : DUMP(prefix, "size: %d", ipt->size);
169 0 : DUMP(bf_dump_prefix_last(prefix), "struct ipt_entry at %p", ipt->entries);
170 :
171 0 : bf_dump_prefix_push(prefix);
172 :
173 : // Loop over each hook to print its rules (if defined).
174 0 : for (i = 0; i < NF_INET_NUMHOOKS; ++i) {
175 0 : if (i == NF_INET_POST_ROUTING)
176 0 : bf_dump_prefix_last(prefix);
177 :
178 0 : if (!ipt_is_hook_enabled(ipt, i)) {
179 0 : DUMP(prefix, "%s: no rule defined", hook_name[i]);
180 0 : continue;
181 : }
182 :
183 0 : DUMP(prefix, "%s (from %x to %x):", hook_name[i], ipt->hook_entry[i],
184 : ipt->underflow[i]);
185 :
186 0 : bf_dump_prefix_push(prefix);
187 :
188 0 : first_rule = ipt_get_first_rule(ipt, i);
189 0 : last_rule = ipt_get_last_rule(ipt, i);
190 : offset = sizeof(*first_rule);
191 :
192 : // Loop over the rules for the current hook.
193 0 : while (first_rule <= last_rule) {
194 0 : if (first_rule == last_rule)
195 0 : bf_dump_prefix_last(prefix);
196 :
197 0 : DUMP(prefix, "struct ipt_entry at %p", first_rule);
198 :
199 0 : bf_dump_prefix_push(prefix);
200 :
201 0 : ipt_dump_ip(&first_rule->ip, prefix);
202 :
203 0 : DUMP(prefix, "target_offset: %d", first_rule->target_offset);
204 0 : DUMP(prefix, "next_offset: %d", first_rule->next_offset);
205 0 : DUMP(prefix, "comefrom: %d", first_rule->comefrom);
206 :
207 0 : ipt_dump_counters(&first_rule->counters, prefix);
208 :
209 : // Loop over the matches for the current rule.
210 0 : while (offset < first_rule->target_offset) {
211 0 : ipt_dump_match(ipt_get_match(first_rule, offset), prefix);
212 0 : offset += ipt_get_match(first_rule, offset)->u.match_size;
213 : }
214 :
215 0 : ipt_dump_target(ipt_get_target(first_rule),
216 : bf_dump_prefix_last(prefix));
217 :
218 0 : bf_dump_prefix_pop(prefix);
219 :
220 0 : if (!first_rule->next_offset)
221 : break;
222 :
223 0 : first_rule = ipt_get_next_rule(first_rule);
224 : }
225 0 : bf_dump_prefix_pop(prefix);
226 : }
227 :
228 0 : bf_dump_prefix_pop(prefix);
229 :
230 : // Force flush, otherwise output on stderr might appear.
231 0 : (void)fflush(stdout);
232 0 : }
|
