1 // SPDX-License-Identifier: GPL-2.0
2 #include <vmlinux.h>
3 #include <bpf/bpf_helpers.h>
4 #include <bpf/bpf_endian.h>
5 
6 #define EAFNOSUPPORT 97
7 #define EPROTO 71
8 #define ENONET 64
9 #define EINVAL 22
10 #define ENOENT 2
11 
12 extern unsigned long CONFIG_HZ __kconfig;
13 
14 int test_einval_bpf_tuple = 0;
15 int test_einval_reserved = 0;
16 int test_einval_netns_id = 0;
17 int test_einval_len_opts = 0;
18 int test_eproto_l4proto = 0;
19 int test_enonet_netns_id = 0;
20 int test_enoent_lookup = 0;
21 int test_eafnosupport = 0;
22 int test_alloc_entry = -EINVAL;
23 int test_insert_entry = -EAFNOSUPPORT;
24 int test_succ_lookup = -ENOENT;
25 u32 test_delta_timeout = 0;
26 u32 test_status = 0;
27 u32 test_insert_lookup_mark = 0;
28 int test_snat_addr = -EINVAL;
29 int test_dnat_addr = -EINVAL;
30 __be32 saddr = 0;
31 __be16 sport = 0;
32 __be32 daddr = 0;
33 __be16 dport = 0;
34 int test_exist_lookup = -ENOENT;
35 u32 test_exist_lookup_mark = 0;
36 
37 enum nf_nat_manip_type___local {
38 	NF_NAT_MANIP_SRC___local,
39 	NF_NAT_MANIP_DST___local
40 };
41 
42 struct nf_conn;
43 
44 struct bpf_ct_opts___local {
45 	s32 netns_id;
46 	s32 error;
47 	u8 l4proto;
48 	u8 reserved[3];
49 } __attribute__((preserve_access_index));
50 
51 struct nf_conn *bpf_xdp_ct_alloc(struct xdp_md *, struct bpf_sock_tuple *, u32,
52 				 struct bpf_ct_opts___local *, u32) __ksym;
53 struct nf_conn *bpf_xdp_ct_lookup(struct xdp_md *, struct bpf_sock_tuple *, u32,
54 				  struct bpf_ct_opts___local *, u32) __ksym;
55 struct nf_conn *bpf_skb_ct_alloc(struct __sk_buff *, struct bpf_sock_tuple *, u32,
56 				 struct bpf_ct_opts___local *, u32) __ksym;
57 struct nf_conn *bpf_skb_ct_lookup(struct __sk_buff *, struct bpf_sock_tuple *, u32,
58 				  struct bpf_ct_opts___local *, u32) __ksym;
59 struct nf_conn *bpf_ct_insert_entry(struct nf_conn *) __ksym;
60 void bpf_ct_release(struct nf_conn *) __ksym;
61 void bpf_ct_set_timeout(struct nf_conn *, u32) __ksym;
62 int bpf_ct_change_timeout(struct nf_conn *, u32) __ksym;
63 int bpf_ct_set_status(struct nf_conn *, u32) __ksym;
64 int bpf_ct_change_status(struct nf_conn *, u32) __ksym;
65 int bpf_ct_set_nat_info(struct nf_conn *, union nf_inet_addr *,
66 			int port, enum nf_nat_manip_type___local) __ksym;
67 
68 static __always_inline void
69 nf_ct_test(struct nf_conn *(*lookup_fn)(void *, struct bpf_sock_tuple *, u32,
70 					struct bpf_ct_opts___local *, u32),
71 	   struct nf_conn *(*alloc_fn)(void *, struct bpf_sock_tuple *, u32,
72 				       struct bpf_ct_opts___local *, u32),
73 	   void *ctx)
74 {
75 	struct bpf_ct_opts___local opts_def = { .l4proto = IPPROTO_TCP, .netns_id = -1 };
76 	struct bpf_sock_tuple bpf_tuple;
77 	struct nf_conn *ct;
78 
79 	__builtin_memset(&bpf_tuple, 0, sizeof(bpf_tuple.ipv4));
80 
81 	ct = lookup_fn(ctx, NULL, 0, &opts_def, sizeof(opts_def));
82 	if (ct)
83 		bpf_ct_release(ct);
84 	else
85 		test_einval_bpf_tuple = opts_def.error;
86 
87 	opts_def.reserved[0] = 1;
88 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
89 		       sizeof(opts_def));
90 	opts_def.reserved[0] = 0;
91 	opts_def.l4proto = IPPROTO_TCP;
92 	if (ct)
93 		bpf_ct_release(ct);
94 	else
95 		test_einval_reserved = opts_def.error;
96 
97 	opts_def.netns_id = -2;
98 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
99 		       sizeof(opts_def));
100 	opts_def.netns_id = -1;
101 	if (ct)
102 		bpf_ct_release(ct);
103 	else
104 		test_einval_netns_id = opts_def.error;
105 
106 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
107 		       sizeof(opts_def) - 1);
108 	if (ct)
109 		bpf_ct_release(ct);
110 	else
111 		test_einval_len_opts = opts_def.error;
112 
113 	opts_def.l4proto = IPPROTO_ICMP;
114 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
115 		       sizeof(opts_def));
116 	opts_def.l4proto = IPPROTO_TCP;
117 	if (ct)
118 		bpf_ct_release(ct);
119 	else
120 		test_eproto_l4proto = opts_def.error;
121 
122 	opts_def.netns_id = 0xf00f;
123 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
124 		       sizeof(opts_def));
125 	opts_def.netns_id = -1;
126 	if (ct)
127 		bpf_ct_release(ct);
128 	else
129 		test_enonet_netns_id = opts_def.error;
130 
131 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
132 		       sizeof(opts_def));
133 	if (ct)
134 		bpf_ct_release(ct);
135 	else
136 		test_enoent_lookup = opts_def.error;
137 
138 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4) - 1, &opts_def,
139 		       sizeof(opts_def));
140 	if (ct)
141 		bpf_ct_release(ct);
142 	else
143 		test_eafnosupport = opts_def.error;
144 
145 	bpf_tuple.ipv4.saddr = bpf_get_prandom_u32(); /* src IP */
146 	bpf_tuple.ipv4.daddr = bpf_get_prandom_u32(); /* dst IP */
147 	bpf_tuple.ipv4.sport = bpf_get_prandom_u32(); /* src port */
148 	bpf_tuple.ipv4.dport = bpf_get_prandom_u32(); /* dst port */
149 
150 	ct = alloc_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
151 		      sizeof(opts_def));
152 	if (ct) {
153 		__u16 sport = bpf_get_prandom_u32();
154 		__u16 dport = bpf_get_prandom_u32();
155 		union nf_inet_addr saddr = {};
156 		union nf_inet_addr daddr = {};
157 		struct nf_conn *ct_ins;
158 
159 		bpf_ct_set_timeout(ct, 10000);
160 		ct->mark = 77;
161 
162 		/* snat */
163 		saddr.ip = bpf_get_prandom_u32();
164 		bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC___local);
165 		/* dnat */
166 		daddr.ip = bpf_get_prandom_u32();
167 		bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST___local);
168 
169 		ct_ins = bpf_ct_insert_entry(ct);
170 		if (ct_ins) {
171 			struct nf_conn *ct_lk;
172 
173 			ct_lk = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4),
174 					  &opts_def, sizeof(opts_def));
175 			if (ct_lk) {
176 				struct nf_conntrack_tuple *tuple;
177 
178 				/* check snat and dnat addresses */
179 				tuple = &ct_lk->tuplehash[IP_CT_DIR_REPLY].tuple;
180 				if (tuple->dst.u3.ip == saddr.ip &&
181 				    tuple->dst.u.all == bpf_htons(sport))
182 					test_snat_addr = 0;
183 				if (tuple->src.u3.ip == daddr.ip &&
184 				    tuple->src.u.all == bpf_htons(dport))
185 					test_dnat_addr = 0;
186 
187 				/* update ct entry timeout */
188 				bpf_ct_change_timeout(ct_lk, 10000);
189 				test_delta_timeout = ct_lk->timeout - bpf_jiffies64();
190 				test_delta_timeout /= CONFIG_HZ;
191 				test_insert_lookup_mark = ct_lk->mark;
192 				bpf_ct_change_status(ct_lk,
193 						     IPS_CONFIRMED | IPS_SEEN_REPLY);
194 				test_status = ct_lk->status;
195 
196 				bpf_ct_release(ct_lk);
197 				test_succ_lookup = 0;
198 			}
199 			bpf_ct_release(ct_ins);
200 			test_insert_entry = 0;
201 		}
202 		test_alloc_entry = 0;
203 	}
204 
205 	bpf_tuple.ipv4.saddr = saddr;
206 	bpf_tuple.ipv4.daddr = daddr;
207 	bpf_tuple.ipv4.sport = sport;
208 	bpf_tuple.ipv4.dport = dport;
209 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
210 		       sizeof(opts_def));
211 	if (ct) {
212 		test_exist_lookup = 0;
213 		if (ct->mark == 42) {
214 			ct->mark++;
215 			test_exist_lookup_mark = ct->mark;
216 		}
217 		bpf_ct_release(ct);
218 	} else {
219 		test_exist_lookup = opts_def.error;
220 	}
221 }
222 
223 SEC("xdp")
224 int nf_xdp_ct_test(struct xdp_md *ctx)
225 {
226 	nf_ct_test((void *)bpf_xdp_ct_lookup, (void *)bpf_xdp_ct_alloc, ctx);
227 	return 0;
228 }
229 
230 SEC("tc")
231 int nf_skb_ct_test(struct __sk_buff *ctx)
232 {
233 	nf_ct_test((void *)bpf_skb_ct_lookup, (void *)bpf_skb_ct_alloc, ctx);
234 	return 0;
235 }
236 
237 char _license[] SEC("license") = "GPL";
238