-/* $FreeBSD: src/sys/netinet6/in6_cksum.c,v 1.1.2.3 2001/07/03 11:01:52 ume Exp $ */
-/* $KAME: in6_cksum.c,v 1.10 2000/12/03 00:53:59 itojun Exp $ */
+/*
+ * Copyright (c) 2009-2012 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* @(#)in_cksum.c 8.1 (Berkeley) 6/10/93
*/
+/*-
+ * Copyright (c) 2008 Joerg Sonnenberger <joerg@NetBSD.org>.
+ * 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 COPYRIGHT HOLDERS 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
+ * COPYRIGHT HOLDERS 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 <sys/param.h>
+#include <machine/endian.h>
#include <sys/mbuf.h>
#include <sys/systm.h>
#include <kern/debug.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
-
-#include <net/net_osdep.h>
+#include <netinet6/ip6_var.h>
/*
* Checksum routine for Internet Protocol family headers (Portable Version).
* code and should be modified for each CPU to be as fast as possible.
*/
-#define ADDCARRY(x) (x > 65535 ? x -= 65535 : x)
-#define REDUCE {l_util.l = sum; sum = l_util.s[0] + l_util.s[1]; ADDCARRY(sum);}
-
/*
- * m MUST contain a continuous IP6 header.
- * off is a offset where TCP/UDP/ICMP6 header starts.
- * len is a total length of a transport segment.
- * (e.g. TCP header + TCP payload)
+ * Compute IPv6 pseudo-header checksum; assumes 16-bit aligned pointers.
*/
-
-u_int16_t
-inet6_cksum(struct mbuf *m, unsigned int nxt, unsigned int off,
- unsigned int len)
+uint16_t
+in6_pseudo(const struct in6_addr *src, const struct in6_addr *dst, uint32_t x)
{
- u_int16_t *w;
- int sum = 0;
- int mlen = 0;
- int byte_swapped = 0;
- struct ip6_hdr *ip6;
- union {
- u_int16_t phs[4];
- struct {
- u_int32_t ph_len;
- u_int8_t ph_zero[3];
- u_int8_t ph_nxt;
- } ph __attribute__((__packed__));
- } uph;
- union {
- u_int8_t c[2];
- u_int16_t s;
- } s_util;
- union {
- u_int16_t s[2];
- u_int32_t l;
- } l_util;
-
- /* sanity check */
- if (m->m_pkthdr.len < off + len) {
- panic("inet6_cksum: mbuf len (%d) < off+len (%d+%d)\n",
- m->m_pkthdr.len, off, len);
- }
-
- if (nxt != 0) {
- bzero(&uph, sizeof (uph));
-
- /*
- * First create IP6 pseudo header and calculate a summary.
- */
- ip6 = mtod(m, struct ip6_hdr *);
- w = (u_int16_t *)&ip6->ip6_src;
- uph.ph.ph_len = htonl(len);
- uph.ph.ph_nxt = nxt;
-
- /* IPv6 source address */
- sum += w[0];
- if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src))
- sum += w[1];
- sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
- sum += w[6]; sum += w[7];
- /* IPv6 destination address */
- sum += w[8];
- if (!IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst))
- sum += w[9];
- sum += w[10]; sum += w[11]; sum += w[12]; sum += w[13];
- sum += w[14]; sum += w[15];
- /* Payload length and upper layer identifier */
- sum += uph.phs[0]; sum += uph.phs[1];
- sum += uph.phs[2]; sum += uph.phs[3];
- }
+ uint32_t sum = 0;
+ const uint16_t *w;
/*
- * Secondly calculate a summary of the first mbuf excluding offset.
- */
- while (m != NULL && off > 0) {
- if (m->m_len <= off)
- off -= m->m_len;
- else
- break;
- m = m->m_next;
- }
- w = (u_int16_t *)(mtod(m, u_char *) + off);
- mlen = m->m_len - off;
- if (len < mlen)
- mlen = len;
- len -= mlen;
- /*
- * Force to even boundary.
+ * IPv6 source address
*/
- if ((1 & (long) w) && (mlen > 0)) {
- REDUCE;
- sum <<= 8;
- s_util.c[0] = *(u_char *)w;
- w = (u_int16_t *)((char *)w + 1);
- mlen--;
- byte_swapped = 1;
- }
+ w = (const uint16_t *)src;
+ sum += w[0];
+ if (!IN6_IS_SCOPE_EMBED(src))
+ sum += w[1];
+ sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
+ sum += w[6]; sum += w[7];
+
/*
- * Unroll the loop to make overhead from
- * branches &c small.
+ * IPv6 destination address
*/
- while ((mlen -= 32) >= 0) {
- sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3];
- sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7];
- sum += w[8]; sum += w[9]; sum += w[10]; sum += w[11];
- sum += w[12]; sum += w[13]; sum += w[14]; sum += w[15];
- w += 16;
- }
- mlen += 32;
- while ((mlen -= 8) >= 0) {
- sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3];
- w += 4;
- }
- mlen += 8;
- if (mlen == 0 && byte_swapped == 0)
- goto next;
- REDUCE;
- while ((mlen -= 2) >= 0) {
- sum += *w++;
- }
- if (byte_swapped) {
- REDUCE;
- sum <<= 8;
- byte_swapped = 0;
- if (mlen == -1) {
- s_util.c[1] = *(char *)w;
- sum += s_util.s;
- mlen = 0;
- } else
- mlen = -1;
- } else if (mlen == -1)
- s_util.c[0] = *(char *)w;
- next:
- m = m->m_next;
+ w = (const uint16_t *)dst;
+ sum += w[0];
+ if (!IN6_IS_SCOPE_EMBED(dst))
+ sum += w[1];
+ sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
+ sum += w[6]; sum += w[7];
/*
- * Lastly calculate a summary of the rest of mbufs.
- */
+ * Caller-supplied value; 'x' could be one of:
+ *
+ * htonl(proto + length), or
+ * htonl(proto + length + sum)
+ **/
+ sum += x;
+
+ /* fold in carry bits */
+ ADDCARRY(sum);
+
+ return (sum);
+}
+
+/*
+ * m MUST contain at least an IPv6 header, if nxt is specified;
+ * nxt is the upper layer protocol number;
+ * off is an offset where TCP/UDP/ICMP6 header starts;
+ * len is a total length of a transport segment (e.g. TCP header + TCP payload)
+ */
+u_int16_t
+inet6_cksum(struct mbuf *m, uint32_t nxt, uint32_t off, uint32_t len)
+{
+ uint32_t sum;
+
+ sum = m_sum16(m, off, len);
+
+ if (nxt != 0) {
+ struct ip6_hdr *ip6;
+ unsigned char buf[sizeof (*ip6)] __attribute__((aligned(8)));
+ uint32_t mlen;
- for (;m && len; m = m->m_next) {
- if (m->m_len == 0)
- continue;
- w = mtod(m, u_int16_t *);
- if (mlen == -1) {
- /*
- * The first byte of this mbuf is the continuation
- * of a word spanning between this mbuf and the
- * last mbuf.
- *
- * s_util.c[0] is already saved when scanning previous
- * mbuf.
- */
- s_util.c[1] = *(char *)w;
- sum += s_util.s;
- w = (u_int16_t *)((char *)w + 1);
- mlen = m->m_len - 1;
- len--;
- } else
- mlen = m->m_len;
- if (len < mlen)
- mlen = len;
- len -= mlen;
/*
- * Force to even boundary.
+ * Sanity check
+ *
+ * Use m_length2() instead of m_length(), as we cannot rely on
+ * the caller setting m_pkthdr.len correctly, if the mbuf is
+ * a M_PKTHDR one.
*/
- if ((1 & (long) w) && (mlen > 0)) {
- REDUCE;
- sum <<= 8;
- s_util.c[0] = *(u_char *)w;
- w = (u_int16_t *)((char *)w + 1);
- mlen--;
- byte_swapped = 1;
+ if ((mlen = m_length2(m, NULL)) < sizeof (*ip6)) {
+ panic("%s: mbuf %p pkt too short (%d) for IPv6 header",
+ __func__, m, mlen);
+ /* NOTREACHED */
}
+
/*
- * Unroll the loop to make overhead from
- * branches &c small.
+ * In case the IPv6 header is not contiguous, or not 32-bit
+ * aligned, copy it to a local buffer. Note here that we
+ * expect the data pointer to point to the IPv6 header.
*/
- while ((mlen -= 32) >= 0) {
- sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3];
- sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7];
- sum += w[8]; sum += w[9]; sum += w[10]; sum += w[11];
- sum += w[12]; sum += w[13]; sum += w[14]; sum += w[15];
- w += 16;
- }
- mlen += 32;
- while ((mlen -= 8) >= 0) {
- sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3];
- w += 4;
+ if ((sizeof (*ip6) > m->m_len) ||
+ !IP6_HDR_ALIGNED_P(mtod(m, caddr_t))) {
+ m_copydata(m, 0, sizeof (*ip6), (caddr_t)buf);
+ ip6 = (struct ip6_hdr *)(void *)buf;
+ } else {
+ ip6 = (struct ip6_hdr *)(void *)(m->m_data);
}
- mlen += 8;
- if (mlen == 0 && byte_swapped == 0)
- continue;
- REDUCE;
- while ((mlen -= 2) >= 0) {
- sum += *w++;
- }
- if (byte_swapped) {
- REDUCE;
- sum <<= 8;
- byte_swapped = 0;
- if (mlen == -1) {
- s_util.c[1] = *(char *)w;
- sum += s_util.s;
- mlen = 0;
- } else
- mlen = -1;
- } else if (mlen == -1)
- s_util.c[0] = *(char *)w;
- }
- if (len)
- printf("inet6_cksum: out of data by %d\n", len);
- if (mlen == -1) {
- /* The last mbuf has odd # of bytes. Follow the
- standard (the odd byte may be shifted left by 8 bits
- or not as determined by endian-ness of the machine) */
- s_util.c[1] = 0;
- sum += s_util.s;
+
+ /* add pseudo header checksum */
+ sum += in6_pseudo(&ip6->ip6_src, &ip6->ip6_dst,
+ htonl(nxt + len));
+
+ /* fold in carry bits */
+ ADDCARRY(sum);
}
- REDUCE;
+
return (~sum & 0xffff);
}
projects / apple / xnu.git / blobdiff