xref: /dpdk/examples/ipsec-secgw/ipip.h (revision cf435a07)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright(c) 2016 Intel Corporation. All rights reserved.
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12  *       notice, this list of conditions and the following disclaimer.
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14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
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21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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32  */
33 
34 #ifndef __IPIP_H__
35 #define __IPIP_H__
36 
37 #include <stdint.h>
38 #include <netinet/in.h>
39 #include <netinet/ip.h>
40 #include <netinet/ip6.h>
41 
42 #include <rte_mbuf.h>
43 
44 static inline void *
45 ipip_outbound(struct rte_mbuf *m, uint32_t offset, uint32_t is_ipv6,
46 		struct ip_addr *src,  struct ip_addr *dst)
47 {
48 	struct ip *inip4, *outip4;
49 	struct ip6_hdr *inip6, *outip6;
50 	uint8_t ds_ecn;
51 
52 	inip4 = rte_pktmbuf_mtod(m, struct ip *);
53 
54 	RTE_ASSERT(inip4->ip_v == IPVERSION || inip4->ip_v == IP6_VERSION);
55 
56 	if (inip4->ip_v == IPVERSION) {
57 		/* XXX This should be done by the forwarding engine instead */
58 		inip4->ip_ttl -= 1;
59 		ds_ecn = inip4->ip_tos;
60 	} else {
61 		inip6 = (struct ip6_hdr *)inip4;
62 		/* XXX This should be done by the forwarding engine instead */
63 		inip6->ip6_hops -= 1;
64 		ds_ecn = ntohl(inip6->ip6_flow) >> 20;
65 	}
66 
67 	if (is_ipv6) {
68 		offset += sizeof(struct ip6_hdr);
69 		outip6 = (struct ip6_hdr *)rte_pktmbuf_prepend(m, offset);
70 
71 		RTE_ASSERT(outip6 != NULL);
72 
73 		/* Per RFC4301 5.1.2.1 */
74 		outip6->ip6_flow = htonl(IP6_VERSION << 28 | ds_ecn << 20);
75 		outip6->ip6_plen = htons(rte_pktmbuf_data_len(m));
76 
77 		outip6->ip6_nxt = IPPROTO_ESP;
78 		outip6->ip6_hops = IPDEFTTL;
79 
80 		memcpy(&outip6->ip6_src.s6_addr, src, 16);
81 		memcpy(&outip6->ip6_dst.s6_addr, dst, 16);
82 
83 		return outip6;
84 	}
85 
86 	offset += sizeof(struct ip);
87 	outip4 = (struct ip *)rte_pktmbuf_prepend(m, offset);
88 
89 	RTE_ASSERT(outip4 != NULL);
90 
91 	/* Per RFC4301 5.1.2.1 */
92 	outip4->ip_v = IPVERSION;
93 	outip4->ip_hl = 5;
94 	outip4->ip_tos = ds_ecn;
95 	outip4->ip_len = htons(rte_pktmbuf_data_len(m));
96 
97 	outip4->ip_id = 0;
98 	outip4->ip_off = 0;
99 
100 	outip4->ip_ttl = IPDEFTTL;
101 	outip4->ip_p = IPPROTO_ESP;
102 
103 	outip4->ip_src.s_addr = src->ip.ip4;
104 	outip4->ip_dst.s_addr = dst->ip.ip4;
105 
106 	return outip4;
107 }
108 
109 static inline struct ip *
110 ip4ip_outbound(struct rte_mbuf *m, uint32_t offset,
111 		struct ip_addr *src,  struct ip_addr *dst)
112 {
113 	return ipip_outbound(m, offset, 0, src, dst);
114 }
115 
116 static inline struct ip6_hdr *
117 ip6ip_outbound(struct rte_mbuf *m, uint32_t offset,
118 		struct ip_addr *src,  struct ip_addr *dst)
119 {
120 	return ipip_outbound(m, offset, 1, src, dst);
121 }
122 
123 static inline void
124 ip4_ecn_setup(struct ip *ip4)
125 {
126 	if (ip4->ip_tos & IPTOS_ECN_MASK)
127 		ip4->ip_tos |= IPTOS_ECN_CE;
128 }
129 
130 static inline void
131 ip6_ecn_setup(struct ip6_hdr *ip6)
132 {
133 	if ((ntohl(ip6->ip6_flow) >> 20) & IPTOS_ECN_MASK)
134 		ip6->ip6_flow = htonl(ntohl(ip6->ip6_flow) |
135 					(IPTOS_ECN_CE << 20));
136 }
137 
138 static inline void
139 ipip_inbound(struct rte_mbuf *m, uint32_t offset)
140 {
141 	struct ip *inip4, *outip4;
142 	struct ip6_hdr *inip6, *outip6;
143 	uint32_t ip_len, set_ecn;
144 
145 	outip4 = rte_pktmbuf_mtod(m, struct ip*);
146 
147 	RTE_ASSERT(outip4->ip_v == IPVERSION || outip4->ip_v == IP6_VERSION);
148 
149 	if (outip4->ip_v == IPVERSION) {
150 		ip_len = sizeof(struct ip);
151 		set_ecn = ((outip4->ip_tos & IPTOS_ECN_CE) == IPTOS_ECN_CE);
152 	} else {
153 		outip6 = (struct ip6_hdr *)outip4;
154 		ip_len = sizeof(struct ip6_hdr);
155 		set_ecn = ntohl(outip6->ip6_flow) >> 20;
156 		set_ecn = ((set_ecn & IPTOS_ECN_CE) == IPTOS_ECN_CE);
157 	}
158 
159 	inip4 = (struct ip *)rte_pktmbuf_adj(m, offset + ip_len);
160 	RTE_ASSERT(inip4->ip_v == IPVERSION || inip4->ip_v == IP6_VERSION);
161 
162 	/* Check packet is still bigger than IP header (inner) */
163 	RTE_ASSERT(rte_pktmbuf_pkt_len(m) > ip_len);
164 
165 	/* RFC4301 5.1.2.1 Note 6 */
166 	if (inip4->ip_v == IPVERSION) {
167 		if (set_ecn)
168 			ip4_ecn_setup(inip4);
169 		/* XXX This should be done by the forwarding engine instead */
170 		inip4->ip_ttl -= 1;
171 	} else {
172 		inip6 = (struct ip6_hdr *)inip4;
173 		if (set_ecn)
174 			ip6_ecn_setup(inip6);
175 		/* XXX This should be done by the forwarding engine instead */
176 		inip6->ip6_hops -= 1;
177 	}
178 }
179 
180 #endif /* __IPIP_H__ */
181