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