in_offload.c revision 1.3
1 /* $NetBSD: in_offload.c,v 1.3 2010/12/11 22:37:46 matt 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 1.3 2010/12/11 22:37:46 matt 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/tcp.h> 41 #include <netinet/in_offload.h> 42 43 struct ip_tso_output_args { 44 struct ifnet *ifp; 45 const struct sockaddr *sa; 46 struct rtentry *rt; 47 }; 48 49 static int ip_tso_output_callback(void *, struct mbuf *); 50 51 static int 52 ip_tso_output_callback(void *vp, struct mbuf *m) 53 { 54 struct ip_tso_output_args *args = vp; 55 struct ifnet *ifp = args->ifp; 56 57 return (*ifp->if_output)(ifp, m, args->sa, args->rt); 58 } 59 60 int 61 ip_tso_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa, 62 struct rtentry *rt) 63 { 64 struct ip_tso_output_args args; 65 66 args.ifp = ifp; 67 args.sa = sa; 68 args.rt = rt; 69 70 return tcp4_segment(m, ip_tso_output_callback, &args); 71 } 72 73 /* 74 * tcp4_segment: handle M_CSUM_TSOv4 by software. 75 * 76 * => always consume m. 77 * => call output_func with output_arg for each segments. 78 */ 79 80 int 81 tcp4_segment(struct mbuf *m, int (*output_func)(void *, struct mbuf *), 82 void *output_arg) 83 { 84 int mss; 85 int iphlen; 86 int thlen; 87 int hlen; 88 int len; 89 struct ip *iph; 90 struct tcphdr *th; 91 uint16_t ipid; 92 uint32_t tcpseq; 93 struct mbuf *hdr = NULL; 94 struct mbuf *t; 95 int error = 0; 96 97 KASSERT((m->m_flags & M_PKTHDR) != 0); 98 KASSERT((m->m_pkthdr.csum_flags & M_CSUM_TSOv4) != 0); 99 100 m->m_pkthdr.csum_flags = 0; 101 102 len = m->m_pkthdr.len; 103 KASSERT(len >= sizeof(*iph) + sizeof(*th)); 104 105 if (m->m_len < sizeof(*iph)) { 106 m = m_pullup(m, sizeof(*iph)); 107 if (m == NULL) { 108 error = ENOMEM; 109 goto quit; 110 } 111 } 112 iph = mtod(m, struct ip *); 113 iphlen = iph->ip_hl * 4; 114 KASSERT(iph->ip_v == IPVERSION); 115 KASSERT(iphlen >= sizeof(*iph)); 116 KASSERT(iph->ip_p == IPPROTO_TCP); 117 ipid = ntohs(iph->ip_id); 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 ip *); 168 KASSERT(iph->ip_v == IPVERSION); 169 iph->ip_len = htons(n->m_pkthdr.len); 170 iph->ip_id = htons(ipid); 171 th = (void *)(mtod(n, char *) + iphlen); 172 th->th_seq = htonl(tcpseq); 173 iph->ip_sum = 0; 174 iph->ip_sum = in_cksum(n, iphlen); 175 th->th_sum = 0; 176 th->th_sum = in4_cksum(n, IPPROTO_TCP, iphlen, thlen + mss); 177 178 error = (*output_func)(output_arg, n); 179 if (error) { 180 goto quit; 181 } 182 183 tcpseq += mss; 184 ipid++; 185 len -= mss; 186 } 187 188 quit: 189 if (hdr != NULL) { 190 m_freem(hdr); 191 } 192 if (m != NULL) { 193 m_freem(m); 194 } 195 196 return error; 197 } 198 199 void 200 ip_undefer_csum(struct mbuf *m, size_t hdrlen, int csum_flags) 201 { 202 KASSERT(m->m_flags & M_PKTHDR); 203 KASSERT((m->m_pkthdr.csum_flags & csum_flags) == csum_flags); 204 uint16_t csum; 205 uint16_t ip_len; 206 uint16_t *csump; 207 size_t iphdrlen; 208 209 if (__predict_true(hdrlen + sizeof(struct ip) <= m->m_len)) { 210 struct ip *ip = (struct ip *)(mtod(m, uint8_t *) + hdrlen); 211 ip_len = ip->ip_len; 212 iphdrlen = ip->ip_hl << 2; 213 csump = &ip->ip_sum; 214 } else { 215 uint8_t ip_vhl; 216 const size_t ip_len_offset = hdrlen + offsetof(struct ip, ip_len); 217 m_copydata(m, hdrlen, sizeof(ip_vhl), &ip_vhl); 218 m_copydata(m, ip_len_offset, sizeof(ip_len), &ip_len); 219 iphdrlen = (ip_vhl & 0x0f) << 2; 220 csump = NULL; 221 } 222 223 if (csum_flags & M_CSUM_IPv4) { 224 const size_t offset = hdrlen + offsetof(struct ip, ip_sum); 225 csum = in4_cksum(m, 0, hdrlen, iphdrlen); 226 if (csump != NULL) { 227 *csump = csum; 228 } else { 229 m_copyback(m, offset, sizeof(uint16_t), &csum); 230 } 231 } 232 233 if (csum_flags & (M_CSUM_UDPv4|M_CSUM_TCPv4)) { 234 size_t l4offset = hdrlen 235 + M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data); 236 237 csum = in4_cksum(m, 0, hdrlen + l4offset, ip_len - l4offset); 238 if (csum == 0 && (csum_flags & M_CSUM_UDPv4) != 0) 239 csum = 0xffff; 240 241 l4offset += M_CSUM_DATA_IPv4_OFFSET(m->m_pkthdr.csum_data); 242 243 if (__predict_true(l4offset + sizeof(uint16_t) <= m->m_len)) { 244 *(uint16_t *)(mtod(m, char *) + l4offset) = csum; 245 } else { 246 m_copyback(m, l4offset, sizeof(csum), (void *) &csum); 247 } 248 } 249 250 m->m_pkthdr.csum_flags ^= csum_flags; 251 } 252
Indexes created Wed Sep 24 05:09:52 GMT 2025