1 | /* $NetBSD: in_offload.c,v 1.7 2016/04/26 09:30:01 ozaki-r Exp $ */ |
2 | |
3 | /*- |
4 | * Copyright (c)2005, 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: in_offload.c,v 1.7 2016/04/26 09:30:01 ozaki-r 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/ip.h> |
40 | #include <netinet/ip_var.h> |
41 | #include <netinet/tcp.h> |
42 | #include <netinet/in_offload.h> |
43 | |
44 | struct ip_tso_output_args { |
45 | struct ifnet *ifp; |
46 | const struct sockaddr *sa; |
47 | struct rtentry *rt; |
48 | }; |
49 | |
50 | static int ip_tso_output_callback(void *, struct mbuf *); |
51 | |
52 | static int |
53 | ip_tso_output_callback(void *vp, struct mbuf *m) |
54 | { |
55 | struct ip_tso_output_args *args = vp; |
56 | struct ifnet *ifp = args->ifp; |
57 | |
58 | return ip_if_output(ifp, m, args->sa, args->rt); |
59 | } |
60 | |
61 | int |
62 | ip_tso_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa, |
63 | struct rtentry *rt) |
64 | { |
65 | struct ip_tso_output_args args; |
66 | |
67 | args.ifp = ifp; |
68 | args.sa = sa; |
69 | args.rt = rt; |
70 | |
71 | return tcp4_segment(m, ip_tso_output_callback, &args); |
72 | } |
73 | |
74 | /* |
75 | * tcp4_segment: handle M_CSUM_TSOv4 by software. |
76 | * |
77 | * => always consume m. |
78 | * => call output_func with output_arg for each segments. |
79 | */ |
80 | |
81 | int |
82 | tcp4_segment(struct mbuf *m, int (*output_func)(void *, struct mbuf *), |
83 | void *output_arg) |
84 | { |
85 | int mss; |
86 | int iphlen; |
87 | int thlen; |
88 | int hlen; |
89 | int len; |
90 | struct ip *iph; |
91 | struct tcphdr *th; |
92 | uint16_t ipid; |
93 | uint32_t tcpseq; |
94 | struct mbuf *hdr = NULL; |
95 | struct mbuf *t; |
96 | int error = 0; |
97 | |
98 | KASSERT((m->m_flags & M_PKTHDR) != 0); |
99 | KASSERT((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) != 0); |
100 | |
101 | m->m_pkthdr.csum_flags = 0; |
102 | |
103 | len = m->m_pkthdr.len; |
104 | KASSERT(len >= sizeof(*iph) + sizeof(*th)); |
105 | |
106 | if (m->m_len < sizeof(*iph)) { |
107 | m = m_pullup(m, sizeof(*iph)); |
108 | if (m == NULL) { |
109 | error = ENOMEM; |
110 | goto quit; |
111 | } |
112 | } |
113 | iph = mtod(m, struct ip *); |
114 | iphlen = iph->ip_hl * 4; |
115 | KASSERT(iph->ip_v == IPVERSION); |
116 | KASSERT(iphlen >= sizeof(*iph)); |
117 | KASSERT(iph->ip_p == IPPROTO_TCP); |
118 | ipid = ntohs(iph->ip_id); |
119 | |
120 | hlen = iphlen + sizeof(*th); |
121 | if (m->m_len < hlen) { |
122 | m = m_pullup(m, hlen); |
123 | if (m == NULL) { |
124 | error = ENOMEM; |
125 | goto quit; |
126 | } |
127 | } |
128 | th = (void *)(mtod(m, char *) + iphlen); |
129 | tcpseq = ntohl(th->th_seq); |
130 | thlen = th->th_off * 4; |
131 | hlen = iphlen + thlen; |
132 | |
133 | mss = m->m_pkthdr.segsz; |
134 | KASSERT(mss != 0); |
135 | KASSERT(len > hlen); |
136 | |
137 | t = m_split(m, hlen, M_NOWAIT); |
138 | if (t == NULL) { |
139 | error = ENOMEM; |
140 | goto quit; |
141 | } |
142 | hdr = m; |
143 | m = t; |
144 | len -= hlen; |
145 | KASSERT(len % mss == 0); |
146 | while (len > 0) { |
147 | struct mbuf *n; |
148 | |
149 | n = m_dup(hdr, 0, hlen, M_NOWAIT); |
150 | if (n == NULL) { |
151 | error = ENOMEM; |
152 | goto quit; |
153 | } |
154 | KASSERT(n->m_len == hlen); /* XXX */ |
155 | |
156 | t = m_split(m, mss, M_NOWAIT); |
157 | if (t == NULL) { |
158 | m_freem(n); |
159 | error = ENOMEM; |
160 | goto quit; |
161 | } |
162 | m_cat(n, m); |
163 | m = t; |
164 | |
165 | KASSERT(n->m_len >= hlen); /* XXX */ |
166 | |
167 | n->m_pkthdr.len = hlen + mss; |
168 | iph = mtod(n, struct ip *); |
169 | KASSERT(iph->ip_v == IPVERSION); |
170 | iph->ip_len = htons(n->m_pkthdr.len); |
171 | iph->ip_id = htons(ipid); |
172 | th = (void *)(mtod(n, char *) + iphlen); |
173 | th->th_seq = htonl(tcpseq); |
174 | iph->ip_sum = 0; |
175 | iph->ip_sum = in_cksum(n, iphlen); |
176 | th->th_sum = 0; |
177 | th->th_sum = in4_cksum(n, IPPROTO_TCP, iphlen, thlen + mss); |
178 | |
179 | error = (*output_func)(output_arg, n); |
180 | if (error) { |
181 | goto quit; |
182 | } |
183 | |
184 | tcpseq += mss; |
185 | ipid++; |
186 | len -= mss; |
187 | } |
188 | |
189 | quit: |
190 | if (hdr != NULL) { |
191 | m_freem(hdr); |
192 | } |
193 | if (m != NULL) { |
194 | m_freem(m); |
195 | } |
196 | |
197 | return error; |
198 | } |
199 | |
200 | void |
201 | ip_undefer_csum(struct mbuf *m, size_t hdrlen, int csum_flags) |
202 | { |
203 | const size_t iphdrlen = M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data); |
204 | uint16_t csum; |
205 | uint16_t ip_len; |
206 | uint16_t *csump; |
207 | |
208 | KASSERT(m->m_flags & M_PKTHDR); |
209 | KASSERT((m->m_pkthdr.csum_flags & csum_flags) == csum_flags); |
210 | |
211 | if (__predict_true(hdrlen + sizeof(struct ip) <= m->m_len)) { |
212 | struct ip *ip = (struct ip *)(mtod(m, uint8_t *) + hdrlen); |
213 | |
214 | ip_len = ip->ip_len; |
215 | csump = &ip->ip_sum; |
216 | } else { |
217 | const size_t ip_len_offset = |
218 | hdrlen + offsetof(struct ip, ip_len); |
219 | |
220 | m_copydata(m, ip_len_offset, sizeof(ip_len), &ip_len); |
221 | csump = NULL; |
222 | } |
223 | ip_len = ntohs(ip_len); |
224 | |
225 | if (csum_flags & M_CSUM_IPv4) { |
226 | csum = in4_cksum(m, 0, hdrlen, iphdrlen); |
227 | if (csump != NULL) { |
228 | *csump = csum; |
229 | } else { |
230 | const size_t offset = hdrlen + |
231 | offsetof(struct ip, ip_sum); |
232 | |
233 | m_copyback(m, offset, sizeof(uint16_t), &csum); |
234 | } |
235 | } |
236 | |
237 | if (csum_flags & (M_CSUM_UDPv4|M_CSUM_TCPv4)) { |
238 | size_t l4offset = hdrlen + iphdrlen; |
239 | |
240 | csum = in4_cksum(m, 0, l4offset, ip_len - l4offset - hdrlen); |
241 | if (csum == 0 && (csum_flags & M_CSUM_UDPv4) != 0) |
242 | csum = 0xffff; |
243 | |
244 | l4offset += M_CSUM_DATA_IPv4_OFFSET(m->m_pkthdr.csum_data); |
245 | |
246 | if (__predict_true(l4offset + sizeof(uint16_t) <= m->m_len)) { |
247 | *(uint16_t *)(mtod(m, char *) + l4offset) = csum; |
248 | } else { |
249 | m_copyback(m, l4offset, sizeof(csum), (void *) &csum); |
250 | } |
251 | } |
252 | |
253 | m->m_pkthdr.csum_flags ^= csum_flags; |
254 | } |
255 | |