| 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 | |