1 /* $OpenBSD: if_trunk.c,v 1.30 2007/01/31 06:20:19 reyk Exp $ */
2
3 /*
4 * Copyright (c) 2005, 2006 Reyk Floeter <reyk@openbsd.org>
5 * Copyright (c) 2007 Andrew Thompson <thompsa@FreeBSD.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 #include <sys/cdefs.h>
21 #include "opt_inet.h"
22 #include "opt_inet6.h"
23
24 #include <sys/param.h>
25 #include <sys/mbuf.h>
26 #include <sys/fnv_hash.h>
27
28 #include <net/ethernet.h>
29 #include <net/infiniband.h>
30
31 #if defined(INET) || defined(INET6)
32 #include <netinet/in.h>
33 #endif
34
35 #ifdef INET
36 #include <netinet/ip.h>
37 #endif
38
39 #ifdef INET6
40 #include <netinet/ip6.h>
41 #endif
42
43 static const void *
m_common_hash_gethdr(const struct mbuf * m,const u_int off,const u_int len,void * buf)44 m_common_hash_gethdr(const struct mbuf *m, const u_int off,
45 const u_int len, void *buf)
46 {
47
48 if (m->m_pkthdr.len < (off + len)) {
49 return (NULL);
50 } else if (m->m_len < (off + len)) {
51 m_copydata(m, off, len, buf);
52 return (buf);
53 }
54 return (mtod(m, char *) + off);
55 }
56
57 uint32_t
m_ether_tcpip_hash_init(void)58 m_ether_tcpip_hash_init(void)
59 {
60 uint32_t seed;
61
62 seed = arc4random();
63 return (fnv_32_buf(&seed, sizeof(seed), FNV1_32_INIT));
64 }
65
66 uint32_t
m_infiniband_tcpip_hash_init(void)67 m_infiniband_tcpip_hash_init(void)
68 {
69 uint32_t seed;
70
71 seed = arc4random();
72 return (fnv_32_buf(&seed, sizeof(seed), FNV1_32_INIT));
73 }
74
75 static inline uint32_t
m_tcpip_hash(const uint32_t flags,const struct mbuf * m,uint32_t p,int off,const uint16_t etype)76 m_tcpip_hash(const uint32_t flags, const struct mbuf *m,
77 uint32_t p, int off, const uint16_t etype)
78 {
79 #if defined(INET) || defined(INET6)
80 union {
81 #ifdef INET
82 struct ip ip;
83 #endif
84 #ifdef INET6
85 struct ip6_hdr ip6;
86 #endif
87 uint32_t port;
88 } buf;
89 #ifdef INET
90 const struct ip *ip;
91 #endif
92 #ifdef INET6
93 const struct ip6_hdr *ip6;
94 #endif
95 #endif
96 switch (etype) {
97 #ifdef INET
98 case ETHERTYPE_IP:
99 ip = m_common_hash_gethdr(m, off, sizeof(*ip), &buf);
100 if (ip == NULL)
101 break;
102 if (flags & MBUF_HASHFLAG_L3) {
103 p = fnv_32_buf(&ip->ip_src, sizeof(struct in_addr), p);
104 p = fnv_32_buf(&ip->ip_dst, sizeof(struct in_addr), p);
105 }
106 if (flags & MBUF_HASHFLAG_L4) {
107 const uint32_t *ports;
108 int iphlen;
109
110 switch (ip->ip_p) {
111 case IPPROTO_TCP:
112 case IPPROTO_UDP:
113 case IPPROTO_SCTP:
114 iphlen = ip->ip_hl << 2;
115 if (iphlen < sizeof(*ip))
116 break;
117 off += iphlen;
118 ports = m_common_hash_gethdr(m,
119 off, sizeof(*ports), &buf);
120 if (ports == NULL)
121 break;
122 p = fnv_32_buf(ports, sizeof(*ports), p);
123 break;
124 default:
125 break;
126 }
127 }
128 break;
129 #endif
130 #ifdef INET6
131 case ETHERTYPE_IPV6:
132 ip6 = m_common_hash_gethdr(m, off, sizeof(*ip6), &buf);
133 if (ip6 == NULL)
134 break;
135 if (flags & MBUF_HASHFLAG_L3) {
136 p = fnv_32_buf(&ip6->ip6_src, sizeof(struct in6_addr), p);
137 p = fnv_32_buf(&ip6->ip6_dst, sizeof(struct in6_addr), p);
138 }
139 if (flags & MBUF_HASHFLAG_L4) {
140 uint32_t flow;
141
142 /* IPv6 flow label */
143 flow = ip6->ip6_flow & IPV6_FLOWLABEL_MASK;
144 p = fnv_32_buf(&flow, sizeof(flow), p);
145 }
146 break;
147 #endif
148 default:
149 break;
150 }
151 return (p);
152 }
153
154 uint32_t
m_ether_tcpip_hash(const uint32_t flags,const struct mbuf * m,uint32_t p)155 m_ether_tcpip_hash(const uint32_t flags, const struct mbuf *m,
156 uint32_t p)
157 {
158 union {
159 struct ether_vlan_header vlan;
160 } buf;
161 const struct ether_header *eh;
162 const struct ether_vlan_header *vlan;
163 int off;
164 uint16_t etype;
165
166 off = sizeof(*eh);
167 if (m->m_len < off)
168 return (p);
169 eh = mtod(m, struct ether_header *);
170 etype = ntohs(eh->ether_type);
171 if (flags & MBUF_HASHFLAG_L2) {
172 p = fnv_32_buf(&eh->ether_shost, ETHER_ADDR_LEN, p);
173 p = fnv_32_buf(&eh->ether_dhost, ETHER_ADDR_LEN, p);
174 }
175 /* Special handling for encapsulating VLAN frames */
176 if ((m->m_flags & M_VLANTAG) && (flags & MBUF_HASHFLAG_L2)) {
177 p = fnv_32_buf(&m->m_pkthdr.ether_vtag,
178 sizeof(m->m_pkthdr.ether_vtag), p);
179 } else if (etype == ETHERTYPE_VLAN) {
180 vlan = m_common_hash_gethdr(m, off, sizeof(*vlan), &buf);
181 if (vlan == NULL)
182 return (p);
183
184 if (flags & MBUF_HASHFLAG_L2)
185 p = fnv_32_buf(&vlan->evl_tag, sizeof(vlan->evl_tag), p);
186 etype = ntohs(vlan->evl_proto);
187 off += sizeof(*vlan) - sizeof(*eh);
188 }
189 return (m_tcpip_hash(flags, m, p, off, etype));
190 }
191
192 uint32_t
m_infiniband_tcpip_hash(const uint32_t flags,const struct mbuf * m,uint32_t p)193 m_infiniband_tcpip_hash(const uint32_t flags, const struct mbuf *m,
194 uint32_t p)
195 {
196 const struct infiniband_header *ibh;
197 int off;
198 uint16_t etype;
199
200 off = sizeof(*ibh);
201 if (m->m_len < off)
202 return (p);
203 ibh = mtod(m, struct infiniband_header *);
204 etype = ntohs(ibh->ib_protocol);
205 if (flags & MBUF_HASHFLAG_L2)
206 p = fnv_32_buf(&ibh->ib_hwaddr, INFINIBAND_ADDR_LEN, p);
207
208 return (m_tcpip_hash(flags, m, p, off, etype));
209 }
210