1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> |
4 | * |
5 | * Development of this code funded by Astaro AG (http://www.astaro.com/) |
6 | */ |
7 | |
8 | #include <asm/unaligned.h> |
9 | #include <linux/kernel.h> |
10 | #include <linux/init.h> |
11 | #include <linux/module.h> |
12 | #include <linux/netlink.h> |
13 | #include <linux/netfilter.h> |
14 | #include <linux/netfilter/nf_tables.h> |
15 | #include <net/netfilter/nf_tables_core.h> |
16 | #include <net/netfilter/nf_tables.h> |
17 | |
18 | struct nft_byteorder { |
19 | u8 sreg; |
20 | u8 dreg; |
21 | enum nft_byteorder_ops op:8; |
22 | u8 len; |
23 | u8 size; |
24 | }; |
25 | |
26 | void nft_byteorder_eval(const struct nft_expr *expr, |
27 | struct nft_regs *regs, |
28 | const struct nft_pktinfo *pkt) |
29 | { |
30 | const struct nft_byteorder *priv = nft_expr_priv(expr); |
31 | u32 *src = ®s->data[priv->sreg]; |
32 | u32 *dst = ®s->data[priv->dreg]; |
33 | u16 *s16, *d16; |
34 | unsigned int i; |
35 | |
36 | s16 = (void *)src; |
37 | d16 = (void *)dst; |
38 | |
39 | switch (priv->size) { |
40 | case 8: { |
41 | u64 src64; |
42 | |
43 | switch (priv->op) { |
44 | case NFT_BYTEORDER_NTOH: |
45 | for (i = 0; i < priv->len / 8; i++) { |
46 | src64 = nft_reg_load64(sreg: &src[i]); |
47 | nft_reg_store64(dreg: &dst[i], |
48 | be64_to_cpu((__force __be64)src64)); |
49 | } |
50 | break; |
51 | case NFT_BYTEORDER_HTON: |
52 | for (i = 0; i < priv->len / 8; i++) { |
53 | src64 = (__force __u64) |
54 | cpu_to_be64(nft_reg_load64(&src[i])); |
55 | nft_reg_store64(dreg: &dst[i], val: src64); |
56 | } |
57 | break; |
58 | } |
59 | break; |
60 | } |
61 | case 4: |
62 | switch (priv->op) { |
63 | case NFT_BYTEORDER_NTOH: |
64 | for (i = 0; i < priv->len / 4; i++) |
65 | dst[i] = ntohl((__force __be32)src[i]); |
66 | break; |
67 | case NFT_BYTEORDER_HTON: |
68 | for (i = 0; i < priv->len / 4; i++) |
69 | dst[i] = (__force __u32)htonl(src[i]); |
70 | break; |
71 | } |
72 | break; |
73 | case 2: |
74 | switch (priv->op) { |
75 | case NFT_BYTEORDER_NTOH: |
76 | for (i = 0; i < priv->len / 2; i++) |
77 | d16[i] = ntohs((__force __be16)s16[i]); |
78 | break; |
79 | case NFT_BYTEORDER_HTON: |
80 | for (i = 0; i < priv->len / 2; i++) |
81 | d16[i] = (__force __u16)htons(s16[i]); |
82 | break; |
83 | } |
84 | break; |
85 | } |
86 | } |
87 | |
88 | static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = { |
89 | [NFTA_BYTEORDER_SREG] = { .type = NLA_U32 }, |
90 | [NFTA_BYTEORDER_DREG] = { .type = NLA_U32 }, |
91 | [NFTA_BYTEORDER_OP] = NLA_POLICY_MAX(NLA_BE32, 255), |
92 | [NFTA_BYTEORDER_LEN] = NLA_POLICY_MAX(NLA_BE32, 255), |
93 | [NFTA_BYTEORDER_SIZE] = NLA_POLICY_MAX(NLA_BE32, 255), |
94 | }; |
95 | |
96 | static int nft_byteorder_init(const struct nft_ctx *ctx, |
97 | const struct nft_expr *expr, |
98 | const struct nlattr * const tb[]) |
99 | { |
100 | struct nft_byteorder *priv = nft_expr_priv(expr); |
101 | u32 size, len; |
102 | int err; |
103 | |
104 | if (tb[NFTA_BYTEORDER_SREG] == NULL || |
105 | tb[NFTA_BYTEORDER_DREG] == NULL || |
106 | tb[NFTA_BYTEORDER_LEN] == NULL || |
107 | tb[NFTA_BYTEORDER_SIZE] == NULL || |
108 | tb[NFTA_BYTEORDER_OP] == NULL) |
109 | return -EINVAL; |
110 | |
111 | priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP])); |
112 | switch (priv->op) { |
113 | case NFT_BYTEORDER_NTOH: |
114 | case NFT_BYTEORDER_HTON: |
115 | break; |
116 | default: |
117 | return -EINVAL; |
118 | } |
119 | |
120 | err = nft_parse_u32_check(attr: tb[NFTA_BYTEORDER_SIZE], U8_MAX, dest: &size); |
121 | if (err < 0) |
122 | return err; |
123 | |
124 | priv->size = size; |
125 | |
126 | switch (priv->size) { |
127 | case 2: |
128 | case 4: |
129 | case 8: |
130 | break; |
131 | default: |
132 | return -EINVAL; |
133 | } |
134 | |
135 | err = nft_parse_u32_check(attr: tb[NFTA_BYTEORDER_LEN], U8_MAX, dest: &len); |
136 | if (err < 0) |
137 | return err; |
138 | |
139 | priv->len = len; |
140 | |
141 | err = nft_parse_register_load(attr: tb[NFTA_BYTEORDER_SREG], sreg: &priv->sreg, |
142 | len: priv->len); |
143 | if (err < 0) |
144 | return err; |
145 | |
146 | return nft_parse_register_store(ctx, attr: tb[NFTA_BYTEORDER_DREG], |
147 | dreg: &priv->dreg, NULL, type: NFT_DATA_VALUE, |
148 | len: priv->len); |
149 | } |
150 | |
151 | static int nft_byteorder_dump(struct sk_buff *skb, |
152 | const struct nft_expr *expr, bool reset) |
153 | { |
154 | const struct nft_byteorder *priv = nft_expr_priv(expr); |
155 | |
156 | if (nft_dump_register(skb, attr: NFTA_BYTEORDER_SREG, reg: priv->sreg)) |
157 | goto nla_put_failure; |
158 | if (nft_dump_register(skb, attr: NFTA_BYTEORDER_DREG, reg: priv->dreg)) |
159 | goto nla_put_failure; |
160 | if (nla_put_be32(skb, attrtype: NFTA_BYTEORDER_OP, htonl(priv->op))) |
161 | goto nla_put_failure; |
162 | if (nla_put_be32(skb, attrtype: NFTA_BYTEORDER_LEN, htonl(priv->len))) |
163 | goto nla_put_failure; |
164 | if (nla_put_be32(skb, attrtype: NFTA_BYTEORDER_SIZE, htonl(priv->size))) |
165 | goto nla_put_failure; |
166 | return 0; |
167 | |
168 | nla_put_failure: |
169 | return -1; |
170 | } |
171 | |
172 | static bool nft_byteorder_reduce(struct nft_regs_track *track, |
173 | const struct nft_expr *expr) |
174 | { |
175 | struct nft_byteorder *priv = nft_expr_priv(expr); |
176 | |
177 | nft_reg_track_cancel(track, dreg: priv->dreg, len: priv->len); |
178 | |
179 | return false; |
180 | } |
181 | |
182 | static const struct nft_expr_ops nft_byteorder_ops = { |
183 | .type = &nft_byteorder_type, |
184 | .size = NFT_EXPR_SIZE(sizeof(struct nft_byteorder)), |
185 | .eval = nft_byteorder_eval, |
186 | .init = nft_byteorder_init, |
187 | .dump = nft_byteorder_dump, |
188 | .reduce = nft_byteorder_reduce, |
189 | }; |
190 | |
191 | struct nft_expr_type nft_byteorder_type __read_mostly = { |
192 | .name = "byteorder" , |
193 | .ops = &nft_byteorder_ops, |
194 | .policy = nft_byteorder_policy, |
195 | .maxattr = NFTA_BYTEORDER_MAX, |
196 | .owner = THIS_MODULE, |
197 | }; |
198 | |