[apple/xnu.git] / bsd / netinet6 / in6_cksum.c

/*
 * 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.
 * 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.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
 */

/*
 * Copyright (c) 1988, 1992, 1993
 *	The Regents of the University of California.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)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 <netinet6/ip6_var.h>

/*
 * Checksum routine for Internet Protocol family headers (Portable Version).
 *
 * This routine is very heavily used in the network
 * code and should be modified for each CPU to be as fast as possible.
 */

/*
 * Compute IPv6 pseudo-header checksum; assumes 16-bit aligned pointers.
 */
uint16_t
in6_pseudo(const struct in6_addr *src, const struct in6_addr *dst, uint32_t x)
{
	uint32_t sum = 0;
	const uint16_t *w;

	/*
	 * IPv6 source address
	 */
	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];

	/*
	 * IPv6 destination address
	 */
	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];

	/*
	 * 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;

		/*
		 * 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 ((mlen = m_length2(m, NULL)) < sizeof (*ip6)) {
			panic("%s: mbuf %p pkt too short (%d) for IPv6 header",
			    __func__, m, mlen);
			/* NOTREACHED */
		}

		/*
		 * 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.
		 */
		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);
		}

		/* add pseudo header checksum */
		sum += in6_pseudo(&ip6->ip6_src, &ip6->ip6_dst,
		    htonl(nxt + len));

		/* fold in carry bits */
		ADDCARRY(sum);
	}

	return (~sum & 0xffff);
}
Commit	Line	Data
b0d623f7	1	/*
39236c6e	2	* Copyright (c) 2009-2012 Apple Inc. All rights reserved.
b0d623f7 A	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
1c79356b A	28
	29	/*
	30	* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
	31	* All rights reserved.
	32	*
	33	* Redistribution and use in source and binary forms, with or without
	34	* modification, are permitted provided that the following conditions
	35	* are met:
	36	* 1. Redistributions of source code must retain the above copyright
	37	* notice, this list of conditions and the following disclaimer.
	38	* 2. Redistributions in binary form must reproduce the above copyright
	39	* notice, this list of conditions and the following disclaimer in the
	40	* documentation and/or other materials provided with the distribution.
	41	* 3. Neither the name of the project nor the names of its contributors
	42	* may be used to endorse or promote products derived from this software
	43	* without specific prior written permission.
	44	*
	45	* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
	46	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	47	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	48	* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
	49	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	50	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	51	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	52	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	53	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	54	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	55	* SUCH DAMAGE.
	56	*/
	57
	58	/*
	59	* Copyright (c) 1988, 1992, 1993
	60	* The Regents of the University of California. All rights reserved.
	61	*
	62	* Redistribution and use in source and binary forms, with or without
	63	* modification, are permitted provided that the following conditions
	64	* are met:
	65	* 1. Redistributions of source code must retain the above copyright
	66	* notice, this list of conditions and the following disclaimer.
	67	* 2. Redistributions in binary form must reproduce the above copyright
	68	* notice, this list of conditions and the following disclaimer in the
	69	* documentation and/or other materials provided with the distribution.
	70	* 3. All advertising materials mentioning features or use of this software
	71	* must display the following acknowledgement:
	72	* This product includes software developed by the University of
	73	* California, Berkeley and its contributors.
	74	* 4. Neither the name of the University nor the names of its contributors
	75	* may be used to endorse or promote products derived from this software
	76	* without specific prior written permission.
	77	*
	78	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	79	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	80	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	81	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	82	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	83	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	84	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	85	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	86	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	87	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	88	* SUCH DAMAGE.
	89	*
	90	* @(#)in_cksum.c 8.1 (Berkeley) 6/10/93
	91	*/
92
b0d623f7 A	93	/*-
	94	* Copyright (c) 2008 Joerg Sonnenberger <joerg@NetBSD.org>.
	95	* All rights reserved.
	96	*
	97	* Redistribution and use in source and binary forms, with or without
	98	* modification, are permitted provided that the following conditions
	99	* are met:
	100	*
	101	* 1. Redistributions of source code must retain the above copyright
	102	* notice, this list of conditions and the following disclaimer.
	103	* 2. Redistributions in binary form must reproduce the above copyright
	104	* notice, this list of conditions and the following disclaimer in
	105	* the documentation and/or other materials provided with the
	106	* distribution.
	107	*
	108	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	109	* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	110	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
	111	* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
	112	* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
	113	* INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
	114	* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	115	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
	116	* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	117	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	118	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	119	* SUCH DAMAGE.
	120	*/
	121
1c79356b	122	#include <sys/param.h>
39236c6e	123	#include <machine/endian.h>
1c79356b A	124	#include <sys/mbuf.h>
1c79356b A	125	#include <sys/systm.h>
2d21ac55	126	#include <kern/debug.h>
1c79356b A	127	#include <netinet/in.h>
1c79356b A	128	#include <netinet/ip6.h>
39236c6e	129	#include <netinet6/ip6_var.h>
b0d623f7	130
1c79356b A	131	/*
	132	* Checksum routine for Internet Protocol family headers (Portable Version).
	133	*
	134	* This routine is very heavily used in the network
	135	* code and should be modified for each CPU to be as fast as possible.
	136	*/
	137
1c79356b	138	/*
39236c6e	139	* Compute IPv6 pseudo-header checksum; assumes 16-bit aligned pointers.
1c79356b	140	*/
39236c6e A	141	uint16_t
39236c6e A	142	in6_pseudo(const struct in6_addr src, const struct in6_addr dst, uint32_t x)
1c79356b	143	{
39236c6e A	144	uint32_t sum = 0;
39236c6e A	145	const uint16_t *w;
1c79356b	146
1c79356b	147	/*
39236c6e	148	* IPv6 source address
1c79356b	149	*/
39236c6e A	150	w = (const uint16_t *)src;
	151	sum += w[0];
	152	if (!IN6_IS_SCOPE_EMBED(src))
	153	sum += w[1];
	154	sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
	155	sum += w[6]; sum += w[7];
	156
1c79356b	157	/*
39236c6e	158	* IPv6 destination address
1c79356b	159	*/
39236c6e A	160	w = (const uint16_t *)dst;
	161	sum += w[0];
	162	if (!IN6_IS_SCOPE_EMBED(dst))
	163	sum += w[1];
	164	sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5];
	165	sum += w[6]; sum += w[7];
1c79356b A	166
1c79356b A	167	/*
39236c6e A	168	* Caller-supplied value; 'x' could be one of:
	169	*
	170	* htonl(proto + length), or
	171	* htonl(proto + length + sum)
	172	**/
	173	sum += x;
	174
	175	/* fold in carry bits */
	176	ADDCARRY(sum);
	177
	178	return (sum);
	179	}
	180
	181	/*
	182	* m MUST contain at least an IPv6 header, if nxt is specified;
	183	* nxt is the upper layer protocol number;
	184	* off is an offset where TCP/UDP/ICMP6 header starts;
	185	* len is a total length of a transport segment (e.g. TCP header + TCP payload)
	186	*/
	187	u_int16_t
	188	inet6_cksum(struct mbuf *m, uint32_t nxt, uint32_t off, uint32_t len)
	189	{
	190	uint32_t sum;
	191
	192	sum = m_sum16(m, off, len);
	193
	194	if (nxt != 0) {
	195	struct ip6_hdr *ip6;
	196	unsigned char buf[sizeof (*ip6)] __attribute__((aligned(8)));
	197	uint32_t mlen;
2d21ac55	198
1c79356b	199	/*
39236c6e A	200	* Sanity check
	201	*
	202	* Use m_length2() instead of m_length(), as we cannot rely on
	203	* the caller setting m_pkthdr.len correctly, if the mbuf is
	204	* a M_PKTHDR one.
1c79356b	205	*/
39236c6e A	206	if ((mlen = m_length2(m, NULL)) < sizeof (*ip6)) {
	207	panic("%s: mbuf %p pkt too short (%d) for IPv6 header",
	208	__func__, m, mlen);
	209	/* NOTREACHED */
1c79356b	210	}
39236c6e	211
1c79356b	212	/*
39236c6e A	213	* In case the IPv6 header is not contiguous, or not 32-bit
	214	* aligned, copy it to a local buffer. Note here that we
	215	* expect the data pointer to point to the IPv6 header.
1c79356b	216	*/
39236c6e A	217	if ((sizeof (*ip6) > m->m_len) \|\|
	218	!IP6_HDR_ALIGNED_P(mtod(m, caddr_t))) {
	219	m_copydata(m, 0, sizeof (*ip6), (caddr_t)buf);
	220	ip6 = (struct ip6_hdr )(void )buf;
	221	} else {
	222	ip6 = (struct ip6_hdr )(void )(m->m_data);
1c79356b	223	}
39236c6e A	224
	225	/* add pseudo header checksum */
	226	sum += in6_pseudo(&ip6->ip6_src, &ip6->ip6_dst,
	227	htonl(nxt + len));
	228
	229	/* fold in carry bits */
	230	ADDCARRY(sum);
1c79356b	231	}
39236c6e	232
1c79356b A	233	return (~sum & 0xffff);
1c79356b A	234	}