/* $NetBSD: in6_offload.c,v 1.12 2018/12/12 01:40:20 rin Exp $ */ /* * Copyright (c)2006 YAMAMOTO Takashi, * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: in6_offload.c,v 1.12 2018/12/12 01:40:20 rin Exp $"); #include #include #include #include #include #include #include #include #include #include #include /* * Handle M_CSUM_TSOv6 in software. Split the TCP payload in chunks of * size MSS, and return mbuf chain consists of them. */ struct mbuf * tcp6_segment(struct mbuf *m, int off) { int mss; int iphlen; int thlen; int hlen; int len; struct ip6_hdr *iph; struct tcphdr *th; uint32_t tcpseq; uint16_t phsum; struct mbuf *hdr = NULL; struct mbuf *m0 = NULL; struct mbuf *prev = NULL; struct mbuf *n, *t; int nsegs; KASSERT((m->m_flags & M_PKTHDR) != 0); KASSERT((m->m_pkthdr.csum_flags & M_CSUM_TSOv6) != 0); m->m_pkthdr.csum_flags = 0; len = m->m_pkthdr.len; KASSERT(len >= off + sizeof(*iph) + sizeof(*th)); hlen = off + sizeof(*iph); if (m->m_len < hlen) { m = m_pullup(m, hlen); if (m == NULL) goto quit; } iph = (void *)(mtod(m, char *) + off); iphlen = sizeof(*iph); KASSERT((iph->ip6_vfc & IPV6_VERSION_MASK) == IPV6_VERSION); KASSERT(iph->ip6_nxt == IPPROTO_TCP); hlen = off + iphlen + sizeof(*th); if (m->m_len < hlen) { m = m_pullup(m, hlen); if (m == NULL) goto quit; } th = (void *)(mtod(m, char *) + off + iphlen); tcpseq = ntohl(th->th_seq); thlen = th->th_off * 4; hlen = off + iphlen + thlen; mss = m->m_pkthdr.segsz; KASSERT(mss != 0); KASSERT(len > hlen); t = m_split(m, hlen, M_NOWAIT); if (t == NULL) goto quit; hdr = m; m = t; len -= hlen; KASSERT(len % mss == 0); iph = (void *)(mtod(hdr, char *) + off); iph->ip6_plen = htons(thlen + mss); phsum = in6_cksum_phdr(&iph->ip6_src, &iph->ip6_dst, htonl(thlen + mss), htonl(IPPROTO_TCP)); for (nsegs = len / mss; nsegs > 0; nsegs--) { if (nsegs > 1) { n = m_dup(hdr, 0, hlen, M_NOWAIT); if (n == NULL) goto quit; } else n = hdr; KASSERT(n->m_len == hlen); /* XXX */ if (nsegs > 1) { t = m_split(m, mss, M_NOWAIT); if (t == NULL) { m_freem(n); goto quit; } } else t = m; m_cat(n, m); m = t; KASSERT(n->m_len >= hlen); /* XXX */ if (m0 == NULL) m0 = n; if (prev != NULL) prev->m_nextpkt = n; n->m_pkthdr.len = hlen + mss; n->m_nextpkt = NULL; /* XXX */ th = (void *)(mtod(n, char *) + off + iphlen); th->th_seq = htonl(tcpseq); th->th_sum = phsum; th->th_sum = in6_cksum(n, 0, off + iphlen, thlen + mss); tcpseq += mss; prev = n; } return m0; quit: if (hdr != NULL) m_freem(hdr); if (m != NULL) m_freem(m); for (m = m0; m != NULL; m = n) { n = m->m_nextpkt; m_freem(m); } return NULL; } int ip6_tso_output(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m, const struct sockaddr_in6 *dst, struct rtentry *rt) { struct mbuf *n; int error = 0; m = tcp6_segment(m, 0); if (m == NULL) return ENOMEM; do { n = m->m_nextpkt; if (error == 0) error = ip6_if_output(ifp, origifp, m, dst, rt); else m_freem(m); m = n; } while (m != NULL); return error; } /* * Compute now in software the IP and TCP/UDP checksums. Cancel the * hardware offloading. */ void in6_undefer_cksum(struct mbuf *m, size_t hdrlen, int csum_flags) { const size_t ip6_plen_offset = hdrlen + offsetof(struct ip6_hdr, ip6_plen); size_t l4hdroff; size_t l4offset; uint16_t plen; uint16_t csum; KASSERT(m->m_flags & M_PKTHDR); KASSERT((m->m_pkthdr.csum_flags & csum_flags) == csum_flags); KASSERT(csum_flags == M_CSUM_UDPv6 || csum_flags == M_CSUM_TCPv6); if (__predict_true(hdrlen + sizeof(struct ip6_hdr) <= m->m_len)) { plen = *(uint16_t *)(mtod(m, char *) + ip6_plen_offset); } else { m_copydata(m, ip6_plen_offset, sizeof(plen), &plen); } plen = ntohs(plen); l4hdroff = M_CSUM_DATA_IPv6_IPHL(m->m_pkthdr.csum_data); l4offset = hdrlen + l4hdroff; csum = in6_cksum(m, 0, l4offset, plen - (l4hdroff - sizeof(struct ip6_hdr))); if (csum == 0 && (csum_flags & M_CSUM_UDPv6) != 0) csum = 0xffff; l4offset += M_CSUM_DATA_IPv6_OFFSET(m->m_pkthdr.csum_data); if (__predict_true((l4offset + sizeof(uint16_t)) <= m->m_len)) { *(uint16_t *)(mtod(m, char *) + l4offset) = csum; } else { m_copyback(m, l4offset, sizeof(csum), (void *) &csum); } m->m_pkthdr.csum_flags ^= csum_flags; } /* * Compute now in software the TCP/UDP checksum. Cancel the hardware * offloading. */ void in6_undefer_cksum_tcpudp(struct mbuf *m) { uint16_t csum, offset; KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0); KASSERT((~m->m_pkthdr.csum_flags & (M_CSUM_UDPv6|M_CSUM_TCPv6)) != 0); KASSERT((m->m_pkthdr.csum_flags & (M_CSUM_UDPv4|M_CSUM_TCPv4|M_CSUM_TSOv4)) == 0); offset = M_CSUM_DATA_IPv6_IPHL(m->m_pkthdr.csum_data); csum = in6_cksum(m, 0, offset, m->m_pkthdr.len - offset); if (csum == 0 && (m->m_pkthdr.csum_flags & M_CSUM_UDPv6) != 0) { csum = 0xffff; } offset += M_CSUM_DATA_IPv6_OFFSET(m->m_pkthdr.csum_data); if ((offset + sizeof(csum)) > m->m_len) { m_copyback(m, offset, sizeof(csum), &csum); } else { *(uint16_t *)(mtod(m, char *) + offset) = csum; } }