IPSEC support in the kernel.

pr_input() routines prototype is also changed to support IPSEC and IPV6
chained protocol headers.

Reviewed by: freebsd-arch, cvs-committers
Obtained from: KAME project

1 files changed, 1236 insertions, 0 deletions

diff --git a/sys/netinet6/esp_core.c b/sys/netinet6/esp_core.c
new file mode 100644
index 0000000..8eb007e
--- /dev/null
+++ b/sys/netinet6/esp_core.c
@@ -0,0 +1,1236 @@
+/*
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#include "opt_inet6.h"
+#include "opt_ipsec.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/domain.h>
+#include <sys/protosw.h>
+#include <sys/socket.h>
+#include <sys/errno.h>
+#include <sys/time.h>
+#include <sys/kernel.h>
+
+#include <net/if.h>
+#include <net/route.h>
+
+#include <netinet/in.h>
+#include <netinet/in_var.h>
+#ifdef INET6
+#include <netinet6/ip6.h>
+#include <netinet6/ip6_var.h>
+#include <netinet6/icmp6.h>
+#endif
+
+#include <netinet6/ipsec.h>
+#include <netinet6/ah.h>
+#ifdef INET6
+#include <netinet6/ipsec6.h>
+#include <netinet6/ah6.h>
+#endif
+#ifdef IPSEC_ESP
+#include <netinet6/esp.h>
+#ifdef INET6
+#include <netinet6/esp6.h>
+#endif
+#endif
+#include <net/pfkeyv2.h>
+#include <netkey/key_var.h>
+#include <netkey/keydb.h>
+#include <crypto/des/des.h>
+#include <crypto/blowfish/blowfish.h>
+#include <crypto/cast128/cast128.h>
+#include <crypto/rc5/rc5.h>
+
+#include <net/net_osdep.h>
+
+static int esp_null_mature __P((struct secasvar *));
+static int esp_null_ivlen __P((struct secasvar *));
+static int esp_null_decrypt __P((struct mbuf *, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_null_encrypt __P((struct mbuf *, size_t, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_descbc_mature __P((struct secasvar *));
+static int esp_descbc_ivlen __P((struct secasvar *));
+static int esp_descbc_decrypt __P((struct mbuf *, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_descbc_encrypt __P((struct mbuf *, size_t, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_cbc_mature __P((struct secasvar *));
+static int esp_blowfish_cbc_decrypt __P((struct mbuf *, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_blowfish_cbc_encrypt __P((struct mbuf *, size_t,
+	size_t, struct secasvar *, struct esp_algorithm *, int));
+static int esp_blowfish_cbc_ivlen __P((struct secasvar *));
+static int esp_cast128cbc_ivlen __P((struct secasvar *));
+static int esp_cast128cbc_decrypt __P((struct mbuf *, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_cast128cbc_encrypt __P((struct mbuf *, size_t, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_3descbc_ivlen __P((struct secasvar *));
+static int esp_3descbc_decrypt __P((struct mbuf *, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_3descbc_encrypt __P((struct mbuf *, size_t, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_rc5cbc_ivlen __P((struct secasvar *));
+static int esp_rc5cbc_decrypt __P((struct mbuf *, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static int esp_rc5cbc_encrypt __P((struct mbuf *, size_t, size_t,
+	struct secasvar *, struct esp_algorithm *, int));
+static void esp_increment_iv __P((struct secasvar *));
+static caddr_t mbuf_find_offset __P((struct mbuf *, size_t, size_t));
+
+/* NOTE: The order depends on SADB_EALG_x in netkey/keyv2.h */
+struct esp_algorithm esp_algorithms[] = {
+	{ 0, 0, 0, 0, 0, 0, 0, },
+	{ 8, esp_descbc_mature, 64, 64,
+		esp_descbc_ivlen, esp_descbc_decrypt, esp_descbc_encrypt, },
+	{ 8, esp_cbc_mature, 192, 192,
+		esp_3descbc_ivlen, esp_3descbc_decrypt, esp_3descbc_encrypt, },
+	{ 1, esp_null_mature, 0, 2048,
+		esp_null_ivlen, esp_null_decrypt, esp_null_encrypt, },
+	{ 8, esp_cbc_mature, 40, 448,
+		esp_blowfish_cbc_ivlen, esp_blowfish_cbc_decrypt,
+		esp_blowfish_cbc_encrypt, },
+	{ 8, esp_cbc_mature, 40, 128,
+		esp_cast128cbc_ivlen, esp_cast128cbc_decrypt,
+		esp_cast128cbc_encrypt, },
+	{ 8, esp_cbc_mature, 40, 2040,
+		esp_rc5cbc_ivlen, esp_rc5cbc_decrypt, esp_rc5cbc_encrypt, },
+};
+
+/*
+ * mbuf assumption: foo_encrypt() assumes that IV part is placed in a single
+ * mbuf, not across multiple mbufs.
+ */
+
+static int
+esp_null_mature(sav)
+	struct secasvar *sav;
+{
+	/* anything is okay */
+	return 0;
+}
+
+static int
+esp_null_ivlen(sav)
+	struct secasvar *sav;
+{
+	return 0;
+}
+
+static int
+esp_null_decrypt(m, off, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;		/* offset to ESP header */
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	return 0; /* do nothing */
+}
+
+static int
+esp_null_encrypt(m, off, plen, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;	/* offset to ESP header */
+	size_t plen;	/* payload length (to be encrypted) */
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	return 0; /* do nothing */
+}
+
+static int
+esp_descbc_mature(sav)
+	struct secasvar *sav;
+{
+	struct esp_algorithm *algo;
+
+	if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B)) {
+		printf("esp_cbc_mature: algorithm incompatible with 4 octets IV length\n");
+		return 1;
+	}
+
+	if (!sav->key_enc) {
+		printf("esp_descbc_mature: no key is given.\n");
+		return 1;
+	}
+	algo = &esp_algorithms[sav->alg_enc];
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_descbc_mature: invalid key length %d.\n",
+			_KEYBITS(sav->key_enc));
+		return 1;
+	}
+
+	/* weak key check */
+	if (des_is_weak_key((C_Block *)_KEYBUF(sav->key_enc))) {
+		printf("esp_descbc_mature: weak key was passed.\n");
+		return 1;
+	}
+
+	return 0;
+}
+
+static int
+esp_descbc_ivlen(sav)
+	struct secasvar *sav;
+{
+	if (sav && (sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B))
+		return 4;
+
+	if (sav && !(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_DERIV))
+		return 4;
+	else
+		return 8;
+}
+
+static int
+esp_descbc_decrypt(m, off, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;		/* offset to ESP header */
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff = 0;
+	size_t bodyoff = 0;
+	u_int8_t *iv;
+	size_t plen;
+	u_int8_t tiv[8];
+	int derived;
+
+	derived = 0;
+	/* sanity check */
+	if (ivlen != sav->ivlen) {
+		printf("esp_descbc_decrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_descbc_decrypt: bad keylen %d\n",
+			_KEYBITS(sav->key_enc));
+		return EINVAL;
+	}
+
+	if (sav->flags & SADB_X_EXT_OLD) {
+		/* RFC 1827 */
+		ivoff = off + sizeof(struct esp);
+		bodyoff = off + sizeof(struct esp) + ivlen;
+		derived = 0;
+	} else {
+		/* RFC 2406 */
+		if (sav->flags & SADB_X_EXT_DERIV) {
+			/*
+			 * draft-ietf-ipsec-ciph-des-derived-00.txt
+			 * uses sequence number field as IV field.
+			 * This draft has been deleted, but you can get from
+			 * ftp://ftp.kame.net/pub/internet-drafts/.
+			 */
+			ivoff = off + sizeof(struct esp);
+			bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
+			ivlen = sizeof(u_int32_t);
+			derived = 1;
+		} else {
+			ivoff = off + sizeof(struct newesp);
+			bodyoff = off + sizeof(struct newesp) + ivlen;
+			derived = 0;
+		}
+	}
+	if (ivlen == 4) {
+		iv = &tiv[0];
+		m_copydata(m, ivoff, 4, &tiv[0]);
+		m_copydata(m, ivoff, 4, &tiv[4]);
+		tiv[4] ^= 0xff;
+		tiv[5] ^= 0xff;
+		tiv[6] ^= 0xff;
+		tiv[7] ^= 0xff;
+	} else if (ivlen == 8) {
+		iv = &tiv[0];
+		m_copydata(m, ivoff, 8, &tiv[0]);
+	} else {
+		printf("esp_descbc_decrypt: unsupported ivlen %d\n", ivlen);
+		return EINVAL;
+	}
+
+	plen = m->m_pkthdr.len;
+	if (plen < bodyoff)
+		panic("esp_descbc_decrypt: too short packet: len=%lu",
+		    (u_long)plen);
+	plen -= bodyoff;
+
+	if (plen % 8) {
+		printf("esp_descbc_decrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+
+    {
+	int deserr;
+	des_key_schedule ks;
+
+	deserr = des_key_sched((C_Block *)_KEYBUF(sav->key_enc), ks);
+	if (deserr != 0) {
+		printf("esp_descbc_decrypt: key error %d\n", deserr);
+		return EINVAL;
+	}
+
+	des_cbc_encrypt(m, bodyoff, plen, ks, (C_Block *)iv, DES_DECRYPT);
+
+	/* for safety */
+	bzero(&ks, sizeof(des_key_schedule));
+    }
+
+	/* for safety */
+	bzero(&tiv[0], sizeof(tiv));
+
+	return 0;
+}
+
+static int
+esp_descbc_encrypt(m, off, plen, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;	/* offset to ESP header */
+	size_t plen;	/* payload length (to be decrypted) */
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff = 0;
+	size_t bodyoff = 0;
+	u_int8_t *iv;
+	u_int8_t tiv[8];
+	int derived;
+
+	derived = 0;
+
+	/* sanity check */
+	if (plen % 8) {
+		printf("esp_descbc_encrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+	if (sav->ivlen != ivlen) {
+		printf("esp_descbc_encrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_descbc_encrypt: bad keylen %d\n",
+			_KEYBITS(sav->key_enc));
+		return EINVAL;
+	}
+
+	if (sav->flags & SADB_X_EXT_OLD) {
+		/* RFC 1827 */
+		/*
+		 * draft-ietf-ipsec-ciph-des-derived-00.txt
+		 * uses sequence number field as IV field.
+		 * This draft has been deleted, see above.
+		 */
+		ivoff = off + sizeof(struct esp);
+		bodyoff = off + sizeof(struct esp) + ivlen;
+		derived = 0;
+	} else {
+		/* RFC 2406 */
+		if (sav->flags & SADB_X_EXT_DERIV) {
+			/*
+			 * draft-ietf-ipsec-ciph-des-derived-00.txt
+			 * uses sequence number field as IV field.
+			 * This draft has been deleted, see above.
+			 */
+			ivoff = off + sizeof(struct esp);
+			bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
+			ivlen = sizeof(u_int32_t);
+			derived = 1;
+		} else {
+			ivoff = off + sizeof(struct newesp);
+			bodyoff = off + sizeof(struct newesp) + ivlen;
+			derived = 0;
+		}
+	}
+
+	if (m->m_pkthdr.len < bodyoff)
+		panic("assumption failed: mbuf too short");
+	iv = mbuf_find_offset(m, ivoff, ivlen);
+	if (!iv)
+		panic("assumption failed: bad mbuf chain");
+	if (ivlen == 4) {
+		if (!derived) {
+			bcopy(sav->iv, &tiv[0], 4);
+			bcopy(sav->iv, &tiv[4], 4);
+			tiv[4] ^= 0xff;
+			tiv[5] ^= 0xff;
+			tiv[6] ^= 0xff;
+			tiv[7] ^= 0xff;
+			bcopy(&tiv[0], iv, 4);
+			iv = &tiv[0];
+		} else {
+			bcopy(iv, &tiv[0], 4);
+			bcopy(iv, &tiv[4], 4);
+			tiv[4] ^= 0xff;
+			tiv[5] ^= 0xff;
+			tiv[6] ^= 0xff;
+			tiv[7] ^= 0xff;
+			iv = &tiv[0];
+		}
+	} else if (ivlen == 8)
+		bcopy((caddr_t)sav->iv, (caddr_t)iv, ivlen);
+	else {
+		printf("esp_descbc_encrypt: unsupported ivlen %d\n", ivlen);
+		return EINVAL;
+	}
+
+    {
+	int deserr;
+	des_key_schedule ks;
+
+	deserr = des_key_sched((C_Block *)_KEYBUF(sav->key_enc), ks);
+	if (deserr != 0) {
+		printf("esp_descbc_encrypt: key error %d\n", deserr);
+		return EINVAL;
+	}
+
+	des_cbc_encrypt(m, bodyoff, plen, ks, (C_Block *)iv, DES_ENCRYPT);
+
+	/* for safety */
+	bzero(&ks, sizeof(des_key_schedule));
+    }
+
+	esp_increment_iv(sav);
+
+	/* for safety */
+	bzero(&tiv[0], sizeof(tiv));
+
+	return 0;
+}
+
+static int
+esp_cbc_mature(sav)
+	struct secasvar *sav;
+{
+	int keylen;
+	struct esp_algorithm *algo;
+
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_cbc_mature: algorithm incompatible with esp-old\n");
+		return 1;
+	}
+	if (sav->flags & SADB_X_EXT_DERIV) {
+		printf("esp_cbc_mature: algorithm incompatible with derived\n");
+		return 1;
+	}
+
+	if (!sav->key_enc) {
+		printf("esp_cbc_mature: no key is given.\n");
+		return 1;
+	}
+	algo = &esp_algorithms[sav->alg_enc];
+	keylen = sav->key_enc->sadb_key_bits;
+	if (keylen < algo->keymin || algo->keymax < keylen) {
+		printf("esp_cbc_mature: invalid key length %d.\n",
+			sav->key_enc->sadb_key_bits);
+		return 1;
+	}
+	switch (sav->alg_enc) {
+	case SADB_EALG_3DESCBC:
+		/* weak key check */
+		if (des_is_weak_key((C_Block *)_KEYBUF(sav->key_enc))
+		 || des_is_weak_key((C_Block *)(_KEYBUF(sav->key_enc) + 8))
+		 || des_is_weak_key((C_Block *)(_KEYBUF(sav->key_enc) + 16))) {
+			printf("esp_cbc_mature: weak key was passed.\n");
+			return 1;
+		}
+		break;
+	case SADB_EALG_BLOWFISHCBC:
+	case SADB_EALG_CAST128CBC:
+	case SADB_EALG_RC5CBC:
+		break;
+	}
+
+	return 0;
+}
+
+static int
+esp_blowfish_cbc_decrypt(m, off, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;		/* offset to ESP header */
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t *iv;
+	u_int8_t tiv[8];
+	size_t plen;
+	static BF_KEY key;	/* made static to avoid kernel stack overflow */
+	int s;
+
+	/* sanity check */
+	if (sav->ivlen != ivlen) {
+		printf("esp_blowfish_cbc_decrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_blowfish_cbc_decrypt: unsupported key length %d: "
+			"need %d to %d bits\n", _KEYBITS(sav->key_enc),
+			algo->keymin, algo->keymax);
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_blowfish_cbc_decrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_blowfish_cbc_decrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+	iv = &tiv[0];
+	m_copydata(m, ivoff, 8, &tiv[0]);
+
+	plen = m->m_pkthdr.len;
+	if (plen < bodyoff)
+		panic("esp_blowfish_cbc_decrypt: too short packet: len=%lu",
+		    (u_long)plen);
+	plen -= bodyoff;
+
+	if (plen % 8) {
+		printf("esp_blowfish_cbc_decrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+
+	s = splnet();	/* XXX correct? */
+
+	BF_set_key(&key, _KEYBITS(sav->key_enc) / 8, _KEYBUF(sav->key_enc));
+	BF_cbc_encrypt_m(m, bodyoff, plen, &key, iv, BF_DECRYPT);
+
+	/* for safety */
+	bzero(&key, sizeof(BF_KEY));
+
+	splx(s);
+
+	/* for safety */
+	bzero(&tiv[0], sizeof(tiv));
+
+	return 0;
+}
+
+static int
+esp_blowfish_cbc_encrypt(m, off, plen, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;	/* offset to ESP header */
+	size_t plen;	/* payload length (to be decrypted) */
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t *iv;
+	static BF_KEY key;	/* made static to avoid kernel stack overflow */
+	int s;
+
+	/* sanity check */
+	if (plen % 8) {
+		printf("esp_blowfish_cbc_encrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+	if (sav->ivlen != ivlen) {
+		printf("esp_blowfish_cbc_encrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_blowfish_cbc_encrypt: unsupported key length %d: "
+			"need %d to %d bits\n", _KEYBITS(sav->key_enc),
+			algo->keymin, algo->keymax);
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_blowfish_cbc_encrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_blowfish_cbc_encrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+
+	if (m->m_pkthdr.len < bodyoff)
+		panic("assumption failed: mbuf too short");
+	iv = mbuf_find_offset(m, ivoff, ivlen);
+	if (!iv)
+		panic("assumption failed: bad mbuf chain");
+
+	bcopy((caddr_t)sav->iv, (caddr_t)iv, ivlen);
+
+	s = splnet();	/* XXX correct? */
+
+	BF_set_key(&key, _KEYBITS(sav->key_enc) / 8, _KEYBUF(sav->key_enc));
+	BF_cbc_encrypt_m(m, bodyoff, plen, &key, iv, BF_ENCRYPT);
+
+	/* for safety */
+	bzero(&key, sizeof(BF_KEY));
+
+	splx(s);
+
+	esp_increment_iv(sav);
+
+	return 0;
+}
+
+static int
+esp_blowfish_cbc_ivlen(sav)
+	struct secasvar *sav;
+{
+	return 8;
+}
+
+static int
+esp_cast128cbc_ivlen(sav)
+	struct secasvar *sav;
+{
+	return 8;
+}
+
+static int
+esp_cast128cbc_decrypt(m, off, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t iv[8];
+	size_t plen;
+
+	/* sanity check */
+	if (ivlen != sav->ivlen) {
+		printf("esp_cast128cbc_decrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || _KEYBITS(sav->key_enc) > algo->keymax) {
+		printf("esp_cast128cbc_decrypt: unsupported key length %d: "
+			"need %d to %d bits\n", _KEYBITS(sav->key_enc),
+			algo->keymin, algo->keymax);
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_cast128cbc_decrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_cast128cbc_decrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+
+	/* copy mbuf's IV into iv */
+	m_copydata(m, ivoff, 8, iv);
+
+	plen = m->m_pkthdr.len;
+	if (plen < bodyoff) {
+		panic("esp_cast128cbc_decrypt: too short packet: len=%lu\n",
+		    (u_long)plen);
+	}
+	plen -= bodyoff;
+
+	if (plen % 8) {
+		printf("esp_cast128cbc_decrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+
+	/* decrypt */
+    {
+	u_int8_t key[16];
+	u_int32_t subkey[32];
+
+	bzero(key, sizeof(key));
+	bcopy(_KEYBUF(sav->key_enc), key, _KEYLEN(sav->key_enc));
+
+	set_cast128_subkey(subkey, key);
+	cast128_cbc_process(m, bodyoff, plen, subkey, iv,
+				_KEYBITS(sav->key_enc) / 8, CAST128_DECRYPT);
+
+	/* for safety */
+	bzero(subkey, sizeof(subkey));
+	bzero(key, sizeof(key));
+    }
+
+	return 0;
+}
+
+static int
+esp_cast128cbc_encrypt(m, off, plen, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;
+	size_t plen;
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t *iv;
+
+	/* sanity check */
+	if (plen % 8) {
+		printf("esp_cast128cbc_encrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+	if (sav->ivlen != ivlen) {
+		printf("esp_cast128cbc_encrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || _KEYBITS(sav->key_enc) > algo->keymax) {
+		printf("esp_cast128cbc_encrypt: unsupported key length %d: "
+			"needs %d to %d bits\n", _KEYBITS(sav->key_enc),
+			algo->keymin, algo->keymax);
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_cast128cbc_encrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_cast128cbc_encrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+
+	if (m->m_pkthdr.len < bodyoff)
+		panic("assumption failed: mbuf too short");
+	iv = mbuf_find_offset(m, ivoff, ivlen);
+	if (!iv)
+		panic("assumption failed: bad mbuf chain");
+
+	bcopy(sav->iv, iv, ivlen);
+
+	/* encrypt */
+    {
+	u_int8_t key[16];
+	u_int32_t subkey[32];
+
+	bzero(key, sizeof(key));
+	bcopy(_KEYBUF(sav->key_enc), key, _KEYLEN(sav->key_enc));
+
+	set_cast128_subkey(subkey, key);
+	cast128_cbc_process(m, bodyoff, plen, subkey, iv,
+				_KEYBITS(sav->key_enc) / 8, CAST128_ENCRYPT);
+
+	/* for safety */
+	bzero(subkey, sizeof(subkey));
+	bzero(key, sizeof(key));
+    }
+
+	esp_increment_iv(sav);
+
+	return 0;
+}
+
+static int
+esp_3descbc_ivlen(sav)
+	struct secasvar *sav;
+{
+	return 8;
+}
+
+static int
+esp_3descbc_decrypt(m, off, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t *iv;
+	size_t plen;
+	u_int8_t tiv[8];
+
+	/* sanity check */
+	if (ivlen != sav->ivlen) {
+		printf("esp_3descbc_decrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_3descbc_decrypt: bad keylen %d\n",
+			_KEYBITS(sav->key_enc));
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_3descbc_decrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_3descbc_decrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+	iv = &tiv[0];
+	m_copydata(m, ivoff, 8, &tiv[0]);
+
+	plen = m->m_pkthdr.len;
+	if (plen < bodyoff)
+		panic("esp_3descbc_decrypt: too short packet: len=%lu",
+		   (u_long)plen);
+
+	plen -= bodyoff;
+
+	if (plen % 8) {
+		printf("esp_3descbc_decrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+
+	/* decrypt packet */
+    {
+	int deserr[3];
+	des_key_schedule ks[3];
+
+	deserr[0] = des_key_sched((C_Block *)_KEYBUF(sav->key_enc),ks[0]);
+	deserr[1] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 8), ks[1]);
+	deserr[2] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 16), ks[2]);
+	if ((deserr[0] != 0) || (deserr[1] != 0) || (deserr[2] != 0)) {
+		printf("esp_3descbc_decrypt: key error %d/%d/%d\n",
+			deserr[0], deserr[1], deserr[2]);
+		return EINVAL;
+	}
+
+	des_3cbc_process(m, bodyoff, plen, ks, (C_Block *)iv, DES_DECRYPT);
+
+	/* for safety */
+	bzero(ks[0], sizeof(des_key_schedule)*3);
+    }
+
+	/* for safety */
+	bzero(&tiv[0], sizeof(tiv));
+
+	return 0;
+}
+
+static int
+esp_3descbc_encrypt(m, off, plen, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;
+	size_t plen;
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t *iv;
+
+	/* sanity check */
+	if (plen % 8) {
+		printf("esp_3descbc_encrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+	if (sav->ivlen != ivlen) {
+		printf("esp_3descbc_encrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || algo->keymax < _KEYBITS(sav->key_enc)) {
+		printf("esp_3descbc_encrypt: bad keylen %d\n",
+			_KEYBITS(sav->key_enc));
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_3descbc_encrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_3descbc_encrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+
+	if (m->m_pkthdr.len < bodyoff)
+		panic("assumption failed: mbuf too short");
+	iv = mbuf_find_offset(m, ivoff, ivlen);
+	if (!iv)
+		panic("assumption failed: bad mbuf chain");
+
+	bcopy((caddr_t)sav->iv, (caddr_t)iv, ivlen);
+
+	/* encrypt packet */
+    {
+	int deserr[3];
+	des_key_schedule ks[3];
+
+	deserr[0] = des_key_sched((C_Block *)_KEYBUF(sav->key_enc),     ks[0]);
+	deserr[1] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 8), ks[1]);
+	deserr[2] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 16), ks[2]);
+	if ((deserr[0] != 0) || (deserr[1] != 0) || (deserr[2] != 0)) {
+		printf("esp_3descbc_encrypt: key error %d/%d/%d\n",
+			deserr[0], deserr[1], deserr[2]);
+		return EINVAL;
+	}
+
+	des_3cbc_process(m, bodyoff, plen, ks, (C_Block *)iv, DES_ENCRYPT);
+
+	/* for safety */
+	bzero(ks[0], sizeof(des_key_schedule)*3);
+    }
+
+	esp_increment_iv(sav);
+
+	return 0;
+}
+
+static int
+esp_rc5cbc_ivlen(sav)
+	struct secasvar *sav;
+{
+	return 8;
+}
+
+static int
+esp_rc5cbc_decrypt(m, off, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t iv[8];
+	size_t plen;
+
+	/* sanity check */
+	if (sav->ivlen != ivlen) {
+		printf("esp_rc5cbc_decrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if ((_KEYBITS(sav->key_enc) < 40) || (_KEYBITS(sav->key_enc) > 2040)) {
+		printf("esp_rc5cbc_decrypt: unsupported key length %d: "
+			"need 40 to 2040 bit\n", _KEYBITS(sav->key_enc));
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_rc5cbc_decrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_rc5cbc_decrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+
+	/* copy mbuf's IV into iv */
+	m_copydata(m, ivoff, 8, iv);
+
+	plen = m->m_pkthdr.len;
+	if (plen < bodyoff) {
+		panic("esp_rc5cbc_decrypt: too short packet: len=%lu",
+			(u_long)plen);
+	}
+	plen -= bodyoff;
+
+	if (plen % 8) {
+		printf("esp_rc5cbc_decrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+
+	/* decrypt */
+    {
+	RC5_WORD e_key[34];
+
+	set_rc5_expandkey(e_key, _KEYBUF(sav->key_enc),
+			_KEYBITS(sav->key_enc) / 8, 16);
+	rc5_cbc_process(m, bodyoff, plen, e_key, iv, RC5_DECRYPT);
+
+	/* for safety */
+	bzero(e_key, sizeof(e_key));
+    }
+
+	return 0;
+}
+
+static int
+esp_rc5cbc_encrypt(m, off, plen, sav, algo, ivlen)
+	struct mbuf *m;
+	size_t off;
+	size_t plen;
+	struct secasvar *sav;
+	struct esp_algorithm *algo;
+	int ivlen;
+{
+	size_t ivoff;
+	size_t bodyoff;
+	u_int8_t *iv;
+
+	/* sanity check */
+	if (plen % 8) {
+		printf("esp_rc5cbc_encrypt: "
+			"payload length must be multiple of 8\n");
+		return EINVAL;
+	}
+	if (sav->ivlen != ivlen) {
+		printf("esp_rc5cbc_encrypt: bad ivlen %d/%d\n",
+			ivlen, sav->ivlen);
+		return EINVAL;
+	}
+	if (_KEYBITS(sav->key_enc) < algo->keymin
+	 || _KEYBITS(sav->key_enc) > algo->keymax) {
+		printf("esp_rc5cbc_encrypt: unsupported key length %d: "
+			"need %d to %d bits\n", _KEYBITS(sav->key_enc),
+			algo->keymin, algo->keymax);
+		return EINVAL;
+	}
+	if (sav->flags & SADB_X_EXT_OLD) {
+		printf("esp_rc5cbc_encrypt: unsupported ESP version\n");
+		return EINVAL;
+	}
+	if (ivlen != 8) {
+		printf("esp_rc5cbc_encrypt: unsupported ivlen %d "
+			"(this should never happen)\n", ivlen);
+		return EINVAL;
+	}
+
+	ivoff = off + sizeof(struct newesp);
+	bodyoff = off + sizeof(struct newesp) + ivlen;
+
+	if (m->m_pkthdr.len < bodyoff)
+		panic("assumption failed: mbuf too short");
+	iv = mbuf_find_offset(m, ivoff, ivlen);
+	if (!iv)
+		panic("assumption failed: bad mbuf chain");
+
+	bcopy(sav->iv, iv, ivlen);
+
+	/* encrypt */
+    {
+	RC5_WORD e_key[34];
+
+	set_rc5_expandkey(e_key, _KEYBUF(sav->key_enc),
+			_KEYBITS(sav->key_enc) / 8, 16);
+	rc5_cbc_process(m, bodyoff, plen, e_key, iv, RC5_ENCRYPT);
+
+	/* for safety */
+	bzero(e_key, sizeof(e_key));
+    }
+
+	esp_increment_iv(sav);
+
+	return 0;
+}
+
+/*
+ * increment iv.
+ */
+static void
+esp_increment_iv(sav)
+	struct secasvar *sav;
+{
+	u_int8_t *x;
+	u_int8_t y;
+	int i;
+
+	y = time_second & 0xff;
+
+	if (!y) y++;
+	x = (u_int8_t *)sav->iv;
+	for (i = 0; i < sav->ivlen; i++) {
+		*x = (*x + y) & 0xff;
+		x++;
+	}
+}
+
+static caddr_t
+mbuf_find_offset(m, off, len)
+	struct mbuf *m;
+	size_t off;
+	size_t len;
+{
+	struct mbuf *n;
+	size_t cnt;
+
+	if (m->m_pkthdr.len < off || m->m_pkthdr.len < off + len)
+		return (caddr_t)NULL;
+	cnt = 0;
+	for (n = m; n; n = n->m_next) {
+		if (cnt + n->m_len <= off) {
+			cnt += n->m_len;
+			continue;
+		}
+		if (cnt <= off && off < cnt + n->m_len
+		 && cnt <= off + len && off + len <= cnt + n->m_len) {
+			return mtod(n, caddr_t) + off - cnt;
+		} else
+			return (caddr_t)NULL;
+	}
+	return (caddr_t)NULL;
+}
+
+/*------------------------------------------------------------*/
+
+int
+esp_auth(m0, skip, length, sav, sum)
+	struct mbuf *m0;
+	size_t skip;	/* offset to ESP header */
+	size_t length;	/* payload length */
+	struct secasvar *sav;
+	u_char *sum;
+{
+	struct mbuf *m;
+	size_t off;
+	struct ah_algorithm_state s;
+	u_char sumbuf[AH_MAXSUMSIZE];
+	struct ah_algorithm *algo;
+	size_t siz;
+
+	/* sanity checks */
+	if (m0->m_pkthdr.len < skip) {
+		printf("esp_auth: mbuf length < skip\n");
+		return EINVAL;
+	}
+	if (m0->m_pkthdr.len < skip + length) {
+		printf("esp_auth: mbuf length < skip + length\n");
+		return EINVAL;
+	}
+	/*
+	 * length of esp part (excluding authentication data) must be 4n,
+	 * since nexthdr must be at offset 4n+3.
+	 */
+	if (length % 4) {
+		printf("esp_auth: length is not multiple of 4\n");
+		return EINVAL;
+	}
+	if (!sav) {
+		printf("esp_auth: NULL SA passed\n");
+		return EINVAL;
+	}
+	if (!sav->alg_auth) {
+		printf("esp_auth: bad ESP auth algorithm passed: %d\n", sav->alg_auth);
+		return EINVAL;
+	}
+
+	m = m0;
+	off = 0;
+
+	algo = &ah_algorithms[sav->alg_auth];
+	siz = (((*algo->sumsiz)(sav) + 3) & ~(4 - 1));
+	if (sizeof(sumbuf) < siz) {
+		printf("esp_auth: AH_MAXSUMSIZE is too small: siz=%lu\n",
+		    (u_long)siz);
+		return EINVAL;
+	}
+
+	/* skip the header */
+	while (skip) {
+		if (!m)
+			panic("mbuf chain?");
+		if (m->m_len <= skip) {
+			skip -= m->m_len;
+			m = m->m_next;
+			off = 0;
+		} else {
+			off = skip;
+			skip = 0;
+		}
+	}
+
+	(*algo->init)(&s, sav);
+	while (0 < length) {
+		if (!m)
+			panic("mbuf chain?");
+
+		if (m->m_len - off < length) {
+			(*algo->update)(&s, mtod(m, u_char *) + off,
+				m->m_len - off);
+			length -= m->m_len - off;
+			m = m->m_next;
+			off = 0;
+		} else {
+			(*algo->update)(&s, mtod(m, u_char *) + off, length);
+			break;
+		}
+	}
+	(*algo->result)(&s, sumbuf);
+	bcopy(sumbuf, sum, siz);	/*XXX*/
+
+	return 0;
+}