1 | /* $NetBSD: in6_offload.c,v 1.6 2011/04/25 22:07:57 yamt Exp $ */ |
2 | |
3 | /*- |
4 | * Copyright (c)2006 YAMAMOTO Takashi, |
5 | * All rights reserved. |
6 | * |
7 | * Redistribution and use in source and binary forms, with or without |
8 | * modification, are permitted provided that the following conditions |
9 | * are met: |
10 | * 1. Redistributions of source code must retain the above copyright |
11 | * notice, this list of conditions and the following disclaimer. |
12 | * 2. Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * |
16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
17 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
18 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
19 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
20 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
21 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
22 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
23 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
24 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
25 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
26 | * SUCH DAMAGE. |
27 | */ |
28 | |
29 | #include <sys/cdefs.h> |
30 | __KERNEL_RCSID(0, "$NetBSD: in6_offload.c,v 1.6 2011/04/25 22:07:57 yamt Exp $" ); |
31 | |
32 | #include <sys/param.h> |
33 | #include <sys/mbuf.h> |
34 | |
35 | #include <net/if.h> |
36 | |
37 | #include <netinet/in.h> |
38 | #include <netinet/in_systm.h> |
39 | #include <netinet/ip6.h> |
40 | #include <netinet/tcp.h> |
41 | #include <netinet6/in6_var.h> |
42 | #include <netinet6/nd6.h> |
43 | #include <netinet6/in6_offload.h> |
44 | |
45 | struct ip6_tso_output_args { |
46 | struct ifnet *ifp; |
47 | struct ifnet *origifp; |
48 | const struct sockaddr_in6 *dst; |
49 | struct rtentry *rt; |
50 | }; |
51 | |
52 | static int ip6_tso_output_callback(void *, struct mbuf *); |
53 | |
54 | static int |
55 | ip6_tso_output_callback(void *vp, struct mbuf *m) |
56 | { |
57 | struct ip6_tso_output_args *args = vp; |
58 | |
59 | return nd6_output(args->ifp, args->origifp, m, args->dst, args->rt); |
60 | } |
61 | |
62 | int |
63 | ip6_tso_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m, |
64 | const struct sockaddr_in6 *dst, struct rtentry *rt) |
65 | { |
66 | struct ip6_tso_output_args args; |
67 | |
68 | args.ifp = ifp; |
69 | args.origifp = origifp; |
70 | args.dst = dst; |
71 | args.rt = rt; |
72 | |
73 | return tcp6_segment(m, ip6_tso_output_callback, &args); |
74 | } |
75 | |
76 | /* |
77 | * tcp6_segment: handle M_CSUM_TSOv6 by software. |
78 | * |
79 | * => always consume m. |
80 | * => call output_func with output_arg for each segments. |
81 | */ |
82 | |
83 | int |
84 | tcp6_segment(struct mbuf *m, int (*output_func)(void *, struct mbuf *), |
85 | void *output_arg) |
86 | { |
87 | int mss; |
88 | int iphlen; |
89 | int thlen; |
90 | int hlen; |
91 | int len; |
92 | struct ip6_hdr *iph; |
93 | struct tcphdr *th; |
94 | uint32_t tcpseq; |
95 | struct mbuf *hdr = NULL; |
96 | struct mbuf *t; |
97 | int error = 0; |
98 | |
99 | KASSERT((m->m_flags & M_PKTHDR) != 0); |
100 | KASSERT((m->m_pkthdr.csum_flags & M_CSUM_TSOv6) != 0); |
101 | |
102 | m->m_pkthdr.csum_flags = 0; |
103 | |
104 | len = m->m_pkthdr.len; |
105 | KASSERT(len >= sizeof(*iph) + sizeof(*th)); |
106 | |
107 | if (m->m_len < sizeof(*iph)) { |
108 | m = m_pullup(m, sizeof(*iph)); |
109 | if (m == NULL) { |
110 | error = ENOMEM; |
111 | goto quit; |
112 | } |
113 | } |
114 | iph = mtod(m, struct ip6_hdr *); |
115 | iphlen = sizeof(*iph); |
116 | KASSERT((iph->ip6_vfc & IPV6_VERSION_MASK) == IPV6_VERSION); |
117 | KASSERT(iph->ip6_nxt == IPPROTO_TCP); |
118 | |
119 | hlen = iphlen + sizeof(*th); |
120 | if (m->m_len < hlen) { |
121 | m = m_pullup(m, hlen); |
122 | if (m == NULL) { |
123 | error = ENOMEM; |
124 | goto quit; |
125 | } |
126 | } |
127 | th = (void *)(mtod(m, char *) + iphlen); |
128 | tcpseq = ntohl(th->th_seq); |
129 | thlen = th->th_off * 4; |
130 | hlen = iphlen + thlen; |
131 | |
132 | mss = m->m_pkthdr.segsz; |
133 | KASSERT(mss != 0); |
134 | KASSERT(len > hlen); |
135 | |
136 | t = m_split(m, hlen, M_NOWAIT); |
137 | if (t == NULL) { |
138 | error = ENOMEM; |
139 | goto quit; |
140 | } |
141 | hdr = m; |
142 | m = t; |
143 | len -= hlen; |
144 | KASSERT(len % mss == 0); |
145 | while (len > 0) { |
146 | struct mbuf *n; |
147 | |
148 | n = m_dup(hdr, 0, hlen, M_NOWAIT); |
149 | if (n == NULL) { |
150 | error = ENOMEM; |
151 | goto quit; |
152 | } |
153 | KASSERT(n->m_len == hlen); /* XXX */ |
154 | |
155 | t = m_split(m, mss, M_NOWAIT); |
156 | if (t == NULL) { |
157 | m_freem(n); |
158 | error = ENOMEM; |
159 | goto quit; |
160 | } |
161 | m_cat(n, m); |
162 | m = t; |
163 | |
164 | KASSERT(n->m_len >= hlen); /* XXX */ |
165 | |
166 | n->m_pkthdr.len = hlen + mss; |
167 | iph = mtod(n, struct ip6_hdr *); |
168 | KASSERT((iph->ip6_vfc & IPV6_VERSION_MASK) == IPV6_VERSION); |
169 | iph->ip6_plen = htons(thlen + mss); |
170 | th = (void *)(mtod(n, char *) + iphlen); |
171 | th->th_seq = htonl(tcpseq); |
172 | th->th_sum = 0; |
173 | th->th_sum = in6_cksum(n, IPPROTO_TCP, iphlen, thlen + mss); |
174 | |
175 | error = (*output_func)(output_arg, n); |
176 | if (error) { |
177 | goto quit; |
178 | } |
179 | |
180 | tcpseq += mss; |
181 | len -= mss; |
182 | } |
183 | |
184 | quit: |
185 | if (hdr != NULL) { |
186 | m_freem(hdr); |
187 | } |
188 | if (m != NULL) { |
189 | m_freem(m); |
190 | } |
191 | |
192 | return error; |
193 | } |
194 | |
195 | void |
196 | ip6_undefer_csum(struct mbuf *m, size_t hdrlen, int csum_flags) |
197 | { |
198 | const size_t ip6_plen_offset = |
199 | hdrlen + offsetof(struct ip6_hdr, ip6_plen); |
200 | size_t l4hdroff; |
201 | size_t l4offset; |
202 | uint16_t plen; |
203 | uint16_t csum; |
204 | |
205 | KASSERT(m->m_flags & M_PKTHDR); |
206 | KASSERT((m->m_pkthdr.csum_flags & csum_flags) == csum_flags); |
207 | KASSERT(csum_flags == M_CSUM_UDPv6 || csum_flags == M_CSUM_TCPv6); |
208 | |
209 | if (__predict_true(hdrlen + sizeof(struct ip6_hdr) <= m->m_len)) { |
210 | plen = *(uint16_t *)(mtod(m, char *) + ip6_plen_offset); |
211 | } else { |
212 | m_copydata(m, ip6_plen_offset, sizeof(plen), &plen); |
213 | } |
214 | plen = ntohs(plen); |
215 | |
216 | l4hdroff = M_CSUM_DATA_IPv6_HL(m->m_pkthdr.csum_data); |
217 | l4offset = hdrlen + l4hdroff; |
218 | csum = in6_cksum(m, 0, l4offset, plen - l4hdroff); |
219 | |
220 | if (csum == 0 && (csum_flags & M_CSUM_UDPv6) != 0) |
221 | csum = 0xffff; |
222 | |
223 | l4offset += M_CSUM_DATA_IPv6_OFFSET(m->m_pkthdr.csum_data); |
224 | |
225 | if (__predict_true((l4offset + sizeof(uint16_t)) <= m->m_len)) { |
226 | *(uint16_t *)(mtod(m, char *) + l4offset) = csum; |
227 | } else { |
228 | m_copyback(m, l4offset, sizeof(csum), (void *) &csum); |
229 | } |
230 | |
231 | m->m_pkthdr.csum_flags ^= csum_flags; |
232 | } |
233 | |