2b6b0bfccb
It seems that PACKET_TAG_IPSEC_IN_CRYPTO_DONE is for network adapters that have IPsec accelerators; a driver sets the mtag to a packet when its device has already encrypted the packet. Unfortunately no driver implements such offload features for long years and seems unlikely to implement them soon. (Note that neither FreeBSD nor Linux doesn't have such drivers.) Let's remove related (unused) codes and simplify the IPsec code.
1076 lines
27 KiB
C
1076 lines
27 KiB
C
/* $NetBSD: xform_esp.c,v 1.57 2017/07/05 03:44:59 ozaki-r Exp $ */
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/* $FreeBSD: src/sys/netipsec/xform_esp.c,v 1.2.2.1 2003/01/24 05:11:36 sam Exp $ */
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/* $OpenBSD: ip_esp.c,v 1.69 2001/06/26 06:18:59 angelos Exp $ */
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/*
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* The authors of this code are John Ioannidis (ji@tla.org),
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* Angelos D. Keromytis (kermit@csd.uch.gr) and
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* Niels Provos (provos@physnet.uni-hamburg.de).
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*
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* The original version of this code was written by John Ioannidis
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* for BSD/OS in Athens, Greece, in November 1995.
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*
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* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
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* by Angelos D. Keromytis.
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*
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* Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
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* and Niels Provos.
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*
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* Additional features in 1999 by Angelos D. Keromytis.
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*
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* Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
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* Angelos D. Keromytis and Niels Provos.
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* Copyright (c) 2001 Angelos D. Keromytis.
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*
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* Permission to use, copy, and modify this software with or without fee
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* is hereby granted, provided that this entire notice is included in
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* all copies of any software which is or includes a copy or
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* modification of this software.
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* You may use this code under the GNU public license if you so wish. Please
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* contribute changes back to the authors under this freer than GPL license
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* so that we may further the use of strong encryption without limitations to
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* all.
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*
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* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
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* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
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* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
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* PURPOSE.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: xform_esp.c,v 1.57 2017/07/05 03:44:59 ozaki-r Exp $");
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#if defined(_KERNEL_OPT)
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#include "opt_inet.h"
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#include "opt_ipsec.h"
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#endif
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/mbuf.h>
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#include <sys/socket.h>
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#include <sys/syslog.h>
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#include <sys/kernel.h>
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#include <sys/sysctl.h>
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#include <sys/socketvar.h> /* for softnet_lock */
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#include <sys/cprng.h>
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#include <net/if.h>
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/ip.h>
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#include <netinet/ip_ecn.h>
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#include <netinet/ip6.h>
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#include <net/route.h>
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#include <netipsec/ipsec.h>
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#include <netipsec/ipsec_private.h>
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#include <netipsec/ah.h>
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#include <netipsec/ah_var.h>
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#include <netipsec/esp.h>
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#include <netipsec/esp_var.h>
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#include <netipsec/xform.h>
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#ifdef INET6
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#include <netinet6/ip6_var.h>
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#include <netipsec/ipsec6.h>
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#endif
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#include <netipsec/key.h>
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#include <netipsec/key_debug.h>
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#include <opencrypto/cryptodev.h>
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#include <opencrypto/xform.h>
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percpu_t *espstat_percpu;
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int esp_enable = 1;
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#ifdef __FreeBSD__
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SYSCTL_DECL(_net_inet_esp);
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SYSCTL_INT(_net_inet_esp, OID_AUTO,
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esp_enable, CTLFLAG_RW, &esp_enable, 0, "");
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SYSCTL_STRUCT(_net_inet_esp, IPSECCTL_STATS,
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stats, CTLFLAG_RD, &espstat, espstat, "");
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#endif /* __FreeBSD__ */
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static int esp_max_ivlen; /* max iv length over all algorithms */
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static int esp_input_cb(struct cryptop *op);
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static int esp_output_cb(struct cryptop *crp);
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const uint8_t esp_stats[256] = { SADB_EALG_STATS_INIT };
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/*
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* NB: this is public for use by the PF_KEY support.
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* NB: if you add support here; be sure to add code to esp_attach below!
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*/
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const struct enc_xform *
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esp_algorithm_lookup(int alg)
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{
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switch (alg) {
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case SADB_EALG_DESCBC:
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return &enc_xform_des;
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case SADB_EALG_3DESCBC:
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return &enc_xform_3des;
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case SADB_X_EALG_AES:
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return &enc_xform_rijndael128;
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case SADB_X_EALG_BLOWFISHCBC:
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return &enc_xform_blf;
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case SADB_X_EALG_CAST128CBC:
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return &enc_xform_cast5;
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case SADB_X_EALG_SKIPJACK:
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return &enc_xform_skipjack;
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case SADB_X_EALG_CAMELLIACBC:
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return &enc_xform_camellia;
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case SADB_X_EALG_AESCTR:
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return &enc_xform_aes_ctr;
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case SADB_X_EALG_AESGCM16:
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return &enc_xform_aes_gcm;
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case SADB_X_EALG_AESGMAC:
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return &enc_xform_aes_gmac;
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case SADB_EALG_NULL:
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return &enc_xform_null;
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}
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return NULL;
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}
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size_t
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esp_hdrsiz(const struct secasvar *sav)
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{
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size_t size;
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if (sav != NULL) {
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/*XXX not right for null algorithm--does it matter??*/
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KASSERT(sav->tdb_encalgxform != NULL);
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if (sav->flags & SADB_X_EXT_OLD)
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size = sizeof(struct esp);
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else
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size = sizeof(struct newesp);
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size += sav->tdb_encalgxform->ivsize + 9;
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/*XXX need alg check???*/
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if (sav->tdb_authalgxform != NULL && sav->replay)
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size += ah_hdrsiz(sav);
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} else {
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/*
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* base header size
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* + max iv length for CBC mode
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* + max pad length
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* + sizeof(pad length field)
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* + sizeof(next header field)
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* + max icv supported.
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*/
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size = sizeof(struct newesp) + esp_max_ivlen + 9 + 16;
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}
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return size;
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}
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/*
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* esp_init() is called when an SPI is being set up.
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*/
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static int
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esp_init(struct secasvar *sav, const struct xformsw *xsp)
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{
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const struct enc_xform *txform;
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struct cryptoini cria, crie, *cr;
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int keylen;
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int error;
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txform = esp_algorithm_lookup(sav->alg_enc);
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if (txform == NULL) {
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DPRINTF(("%s: unsupported encryption algorithm %d\n", __func__,
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sav->alg_enc));
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return EINVAL;
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}
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if (sav->key_enc == NULL) {
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DPRINTF(("%s: no encoding key for %s algorithm\n", __func__,
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txform->name));
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return EINVAL;
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}
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if ((sav->flags&(SADB_X_EXT_OLD|SADB_X_EXT_IV4B)) == SADB_X_EXT_IV4B) {
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DPRINTF(("%s: 4-byte IV not supported with protocol\n",
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__func__));
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return EINVAL;
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}
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keylen = _KEYLEN(sav->key_enc);
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if (txform->minkey > keylen || keylen > txform->maxkey) {
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DPRINTF(("%s: invalid key length %u, must be in "
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"the range [%u..%u] for algorithm %s\n", __func__,
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keylen, txform->minkey, txform->maxkey, txform->name));
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return EINVAL;
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}
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sav->ivlen = txform->ivsize;
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/*
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* Setup AH-related state.
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*/
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if (sav->alg_auth != 0) {
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error = ah_init0(sav, xsp, &cria);
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if (error)
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return error;
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}
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/* NB: override anything set in ah_init0 */
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sav->tdb_xform = xsp;
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sav->tdb_encalgxform = txform;
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switch (sav->alg_enc) {
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case SADB_X_EALG_AESGCM16:
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case SADB_X_EALG_AESGMAC:
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switch (keylen) {
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case 20:
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sav->alg_auth = SADB_X_AALG_AES128GMAC;
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sav->tdb_authalgxform = &auth_hash_gmac_aes_128;
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break;
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case 28:
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sav->alg_auth = SADB_X_AALG_AES192GMAC;
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sav->tdb_authalgxform = &auth_hash_gmac_aes_192;
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break;
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case 36:
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sav->alg_auth = SADB_X_AALG_AES256GMAC;
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sav->tdb_authalgxform = &auth_hash_gmac_aes_256;
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break;
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default:
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DPRINTF(("%s: invalid key length %u, must be either of "
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"20, 28 or 36\n", __func__, keylen));
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return EINVAL;
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}
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memset(&cria, 0, sizeof(cria));
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cria.cri_alg = sav->tdb_authalgxform->type;
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cria.cri_klen = _KEYBITS(sav->key_enc);
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cria.cri_key = _KEYBUF(sav->key_enc);
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break;
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default:
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break;
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}
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/* Initialize crypto session. */
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memset(&crie, 0, sizeof(crie));
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crie.cri_alg = sav->tdb_encalgxform->type;
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crie.cri_klen = _KEYBITS(sav->key_enc);
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crie.cri_key = _KEYBUF(sav->key_enc);
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/* XXX Rounds ? */
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if (sav->tdb_authalgxform && sav->tdb_encalgxform) {
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/* init both auth & enc */
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crie.cri_next = &cria;
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cr = &crie;
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} else if (sav->tdb_encalgxform) {
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cr = &crie;
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} else if (sav->tdb_authalgxform) {
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cr = &cria;
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} else {
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/* XXX cannot happen? */
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DPRINTF(("%s: no encoding OR authentication xform!\n",
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__func__));
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return EINVAL;
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}
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return crypto_newsession(&sav->tdb_cryptoid, cr, crypto_support);
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}
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/*
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* Paranoia.
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*/
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static int
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esp_zeroize(struct secasvar *sav)
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{
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/* NB: ah_zerorize free's the crypto session state */
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int error = ah_zeroize(sav);
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if (sav->key_enc)
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memset(_KEYBUF(sav->key_enc), 0, _KEYLEN(sav->key_enc));
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sav->tdb_encalgxform = NULL;
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sav->tdb_xform = NULL;
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return error;
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}
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/*
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* ESP input processing, called (eventually) through the protocol switch.
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*/
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static int
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esp_input(struct mbuf *m, const struct secasvar *sav, int skip, int protoff)
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{
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const struct auth_hash *esph;
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const struct enc_xform *espx;
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struct tdb_crypto *tc;
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int plen, alen, hlen, error;
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struct newesp *esp;
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struct cryptodesc *crde;
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struct cryptop *crp;
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IPSEC_SPLASSERT_SOFTNET(__func__);
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KASSERT(sav != NULL);
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KASSERT(sav->tdb_encalgxform != NULL);
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KASSERTMSG((skip&3) == 0 && (m->m_pkthdr.len&3) == 0,
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"misaligned packet, skip %u pkt len %u",
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skip, m->m_pkthdr.len);
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/* XXX don't pullup, just copy header */
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IP6_EXTHDR_GET(esp, struct newesp *, m, skip, sizeof(struct newesp));
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esph = sav->tdb_authalgxform;
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espx = sav->tdb_encalgxform;
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/* Determine the ESP header length */
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if (sav->flags & SADB_X_EXT_OLD)
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hlen = sizeof(struct esp) + sav->ivlen;
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else
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hlen = sizeof(struct newesp) + sav->ivlen;
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/* Authenticator hash size */
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alen = esph ? esph->authsize : 0;
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/*
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* Verify payload length is multiple of encryption algorithm
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* block size.
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*
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* NB: This works for the null algorithm because the blocksize
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* is 4 and all packets must be 4-byte aligned regardless
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* of the algorithm.
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*/
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plen = m->m_pkthdr.len - (skip + hlen + alen);
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if ((plen & (espx->blocksize - 1)) || (plen <= 0)) {
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char buf[IPSEC_ADDRSTRLEN];
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DPRINTF(("%s: payload of %d octets not a multiple of %d octets,"
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" SA %s/%08lx\n", __func__, plen, espx->blocksize,
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ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
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(u_long) ntohl(sav->spi)));
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ESP_STATINC(ESP_STAT_BADILEN);
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m_freem(m);
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return EINVAL;
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}
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/*
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* Check sequence number.
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*/
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if (esph && sav->replay && !ipsec_chkreplay(ntohl(esp->esp_seq), sav)) {
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char logbuf[IPSEC_LOGSASTRLEN];
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DPRINTF(("%s: packet replay check for %s\n", __func__,
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ipsec_logsastr(sav, logbuf, sizeof(logbuf)))); /*XXX*/
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ESP_STATINC(ESP_STAT_REPLAY);
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m_freem(m);
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return ENOBUFS; /*XXX*/
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}
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/* Update the counters */
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ESP_STATADD(ESP_STAT_IBYTES, m->m_pkthdr.len - skip - hlen - alen);
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/* Get crypto descriptors */
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crp = crypto_getreq(esph && espx ? 2 : 1);
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if (crp == NULL) {
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DPRINTF(("%s: failed to acquire crypto descriptors\n",
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__func__));
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error = ENOBUFS;
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goto out;
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}
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/* Get IPsec-specific opaque pointer */
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size_t extra = esph == NULL ? 0 : alen;
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tc = malloc(sizeof(*tc) + extra, M_XDATA, M_NOWAIT|M_ZERO);
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if (tc == NULL) {
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DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
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error = ENOBUFS;
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goto out1;
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}
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error = m_makewritable(&m, 0, m->m_pkthdr.len, M_NOWAIT);
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if (error) {
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DPRINTF(("%s: m_makewritable failed\n", __func__));
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goto out2;
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}
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if (esph) {
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struct cryptodesc *crda;
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KASSERT(crp->crp_desc != NULL);
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crda = crp->crp_desc;
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/* Authentication descriptor */
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crda->crd_skip = skip;
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if (espx && espx->type == CRYPTO_AES_GCM_16)
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crda->crd_len = hlen - sav->ivlen;
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else
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crda->crd_len = m->m_pkthdr.len - (skip + alen);
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crda->crd_inject = m->m_pkthdr.len - alen;
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crda->crd_alg = esph->type;
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if (espx && (espx->type == CRYPTO_AES_GCM_16 ||
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espx->type == CRYPTO_AES_GMAC)) {
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crda->crd_key = _KEYBUF(sav->key_enc);
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crda->crd_klen = _KEYBITS(sav->key_enc);
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} else {
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crda->crd_key = _KEYBUF(sav->key_auth);
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crda->crd_klen = _KEYBITS(sav->key_auth);
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}
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/* Copy the authenticator */
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m_copydata(m, m->m_pkthdr.len - alen, alen, (tc + 1));
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/* Chain authentication request */
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crde = crda->crd_next;
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} else {
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crde = crp->crp_desc;
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}
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|
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/* Crypto operation descriptor */
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crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
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crp->crp_flags = CRYPTO_F_IMBUF;
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crp->crp_buf = m;
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crp->crp_callback = esp_input_cb;
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crp->crp_sid = sav->tdb_cryptoid;
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crp->crp_opaque = tc;
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|
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/* These are passed as-is to the callback */
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tc->tc_spi = sav->spi;
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tc->tc_dst = sav->sah->saidx.dst;
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tc->tc_proto = sav->sah->saidx.proto;
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tc->tc_protoff = protoff;
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tc->tc_skip = skip;
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|
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/* Decryption descriptor */
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if (espx) {
|
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KASSERTMSG(crde != NULL, "null esp crypto descriptor");
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crde->crd_skip = skip + hlen;
|
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if (espx->type == CRYPTO_AES_GMAC)
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crde->crd_len = 0;
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else
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crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen);
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crde->crd_inject = skip + hlen - sav->ivlen;
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crde->crd_alg = espx->type;
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crde->crd_key = _KEYBUF(sav->key_enc);
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crde->crd_klen = _KEYBITS(sav->key_enc);
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/* XXX Rounds ? */
|
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}
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|
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return crypto_dispatch(crp);
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|
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out2:
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free(tc, M_XDATA);
|
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out1:
|
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crypto_freereq(crp);
|
|
out:
|
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ESP_STATINC(ESP_STAT_CRYPTO);
|
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m_freem(m);
|
|
return error;
|
|
}
|
|
|
|
#ifdef INET6
|
|
#define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff) do { \
|
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if (saidx->dst.sa.sa_family == AF_INET6) { \
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|
error = ipsec6_common_input_cb(m, sav, skip, protoff); \
|
|
} else { \
|
|
error = ipsec4_common_input_cb(m, sav, skip, protoff); \
|
|
} \
|
|
} while (0)
|
|
#else
|
|
#define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff) \
|
|
(error = ipsec4_common_input_cb(m, sav, skip, protoff))
|
|
#endif
|
|
|
|
/*
|
|
* ESP input callback from the crypto driver.
|
|
*/
|
|
static int
|
|
esp_input_cb(struct cryptop *crp)
|
|
{
|
|
char buf[IPSEC_ADDRSTRLEN];
|
|
uint8_t lastthree[3], aalg[AH_ALEN_MAX];
|
|
int s, hlen, skip, protoff, error;
|
|
struct mbuf *m;
|
|
const struct auth_hash *esph;
|
|
struct tdb_crypto *tc;
|
|
struct secasvar *sav;
|
|
struct secasindex *saidx;
|
|
void *ptr;
|
|
uint16_t dport;
|
|
uint16_t sport;
|
|
|
|
KASSERT(crp->crp_desc != NULL);
|
|
KASSERT(crp->crp_opaque != NULL);
|
|
|
|
tc = crp->crp_opaque;
|
|
skip = tc->tc_skip;
|
|
protoff = tc->tc_protoff;
|
|
m = crp->crp_buf;
|
|
|
|
/* find the source port for NAT-T */
|
|
nat_t_ports_get(m, &dport, &sport);
|
|
|
|
s = splsoftnet();
|
|
mutex_enter(softnet_lock);
|
|
|
|
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, sport, dport);
|
|
if (sav == NULL) {
|
|
ESP_STATINC(ESP_STAT_NOTDB);
|
|
DPRINTF(("%s: SA expired while in crypto "
|
|
"(SA %s/%08lx proto %u)\n", __func__,
|
|
ipsec_address(&tc->tc_dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(tc->tc_spi), tc->tc_proto));
|
|
error = ENOBUFS; /*XXX*/
|
|
goto bad;
|
|
}
|
|
|
|
saidx = &sav->sah->saidx;
|
|
KASSERTMSG(saidx->dst.sa.sa_family == AF_INET ||
|
|
saidx->dst.sa.sa_family == AF_INET6,
|
|
"unexpected protocol family %u", saidx->dst.sa.sa_family);
|
|
|
|
esph = sav->tdb_authalgxform;
|
|
|
|
/* Check for crypto errors */
|
|
if (crp->crp_etype) {
|
|
/* Reset the session ID */
|
|
if (sav->tdb_cryptoid != 0)
|
|
sav->tdb_cryptoid = crp->crp_sid;
|
|
|
|
if (crp->crp_etype == EAGAIN) {
|
|
KEY_FREESAV(&sav);
|
|
mutex_exit(softnet_lock);
|
|
splx(s);
|
|
return crypto_dispatch(crp);
|
|
}
|
|
|
|
ESP_STATINC(ESP_STAT_NOXFORM);
|
|
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
|
|
error = crp->crp_etype;
|
|
goto bad;
|
|
}
|
|
|
|
/* Shouldn't happen... */
|
|
if (m == NULL) {
|
|
ESP_STATINC(ESP_STAT_CRYPTO);
|
|
DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
ESP_STATINC(ESP_STAT_HIST + esp_stats[sav->alg_enc]);
|
|
|
|
/* If authentication was performed, check now. */
|
|
if (esph != NULL) {
|
|
/*
|
|
* If we have a tag, it means an IPsec-aware NIC did
|
|
* the verification for us. Otherwise we need to
|
|
* check the authentication calculation.
|
|
*/
|
|
AH_STATINC(AH_STAT_HIST + ah_stats[sav->alg_auth]);
|
|
/* Copy the authenticator from the packet */
|
|
m_copydata(m, m->m_pkthdr.len - esph->authsize,
|
|
esph->authsize, aalg);
|
|
|
|
ptr = (tc + 1);
|
|
|
|
/* Verify authenticator */
|
|
if (!consttime_memequal(ptr, aalg, esph->authsize)) {
|
|
DPRINTF(("%s: authentication hash mismatch "
|
|
"for packet in SA %s/%08lx\n", __func__,
|
|
ipsec_address(&saidx->dst, buf,
|
|
sizeof(buf)), (u_long) ntohl(sav->spi)));
|
|
ESP_STATINC(ESP_STAT_BADAUTH);
|
|
error = EACCES;
|
|
goto bad;
|
|
}
|
|
|
|
/* Remove trailing authenticator */
|
|
m_adj(m, -(esph->authsize));
|
|
}
|
|
|
|
/* Release the crypto descriptors */
|
|
free(tc, M_XDATA), tc = NULL;
|
|
crypto_freereq(crp), crp = NULL;
|
|
|
|
/*
|
|
* Packet is now decrypted.
|
|
*/
|
|
m->m_flags |= M_DECRYPTED;
|
|
|
|
/*
|
|
* Update replay sequence number, if appropriate.
|
|
*/
|
|
if (sav->replay) {
|
|
uint32_t seq;
|
|
|
|
m_copydata(m, skip + offsetof(struct newesp, esp_seq),
|
|
sizeof(seq), &seq);
|
|
if (ipsec_updatereplay(ntohl(seq), sav)) {
|
|
char logbuf[IPSEC_LOGSASTRLEN];
|
|
DPRINTF(("%s: packet replay check for %s\n", __func__,
|
|
ipsec_logsastr(sav, logbuf, sizeof(logbuf))));
|
|
ESP_STATINC(ESP_STAT_REPLAY);
|
|
error = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
}
|
|
|
|
/* Determine the ESP header length */
|
|
if (sav->flags & SADB_X_EXT_OLD)
|
|
hlen = sizeof(struct esp) + sav->ivlen;
|
|
else
|
|
hlen = sizeof(struct newesp) + sav->ivlen;
|
|
|
|
/* Remove the ESP header and IV from the mbuf. */
|
|
error = m_striphdr(m, skip, hlen);
|
|
if (error) {
|
|
ESP_STATINC(ESP_STAT_HDROPS);
|
|
DPRINTF(("%s: bad mbuf chain, SA %s/%08lx\n", __func__,
|
|
ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(sav->spi)));
|
|
goto bad;
|
|
}
|
|
|
|
/* Save the last three bytes of decrypted data */
|
|
m_copydata(m, m->m_pkthdr.len - 3, 3, lastthree);
|
|
|
|
/* Verify pad length */
|
|
if (lastthree[1] + 2 > m->m_pkthdr.len - skip) {
|
|
ESP_STATINC(ESP_STAT_BADILEN);
|
|
DPRINTF(("%s: invalid padding length %d "
|
|
"for %u byte packet in SA %s/%08lx\n", __func__,
|
|
lastthree[1], m->m_pkthdr.len - skip,
|
|
ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(sav->spi)));
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
|
|
/* Verify correct decryption by checking the last padding bytes */
|
|
if ((sav->flags & SADB_X_EXT_PMASK) != SADB_X_EXT_PRAND) {
|
|
if (lastthree[1] != lastthree[0] && lastthree[1] != 0) {
|
|
ESP_STATINC(ESP_STAT_BADENC);
|
|
DPRINTF(("%s: decryption failed for packet in SA "
|
|
"%s/%08lx\n", __func__,
|
|
ipsec_address(&sav->sah->saidx.dst, buf,
|
|
sizeof(buf)), (u_long) ntohl(sav->spi)));
|
|
DPRINTF(("%s: %x %x\n", __func__, lastthree[0],
|
|
lastthree[1]));
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
}
|
|
|
|
/* Trim the mbuf chain to remove trailing authenticator and padding */
|
|
m_adj(m, -(lastthree[1] + 2));
|
|
|
|
/* Restore the Next Protocol field */
|
|
m_copyback(m, protoff, sizeof(uint8_t), lastthree + 2);
|
|
|
|
IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff);
|
|
|
|
KEY_FREESAV(&sav);
|
|
mutex_exit(softnet_lock);
|
|
splx(s);
|
|
return error;
|
|
bad:
|
|
if (sav)
|
|
KEY_FREESAV(&sav);
|
|
mutex_exit(softnet_lock);
|
|
splx(s);
|
|
if (m != NULL)
|
|
m_freem(m);
|
|
if (tc != NULL)
|
|
free(tc, M_XDATA);
|
|
if (crp != NULL)
|
|
crypto_freereq(crp);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* ESP output routine, called by ipsec[46]_process_packet().
|
|
*/
|
|
static int
|
|
esp_output(
|
|
struct mbuf *m,
|
|
struct ipsecrequest *isr,
|
|
struct mbuf **mp,
|
|
int skip,
|
|
int protoff
|
|
)
|
|
{
|
|
char buf[IPSEC_ADDRSTRLEN];
|
|
const struct enc_xform *espx;
|
|
const struct auth_hash *esph;
|
|
int hlen, rlen, padding, blks, alen, i, roff;
|
|
struct mbuf *mo = NULL;
|
|
struct tdb_crypto *tc;
|
|
const struct secasvar *sav;
|
|
struct secasindex *saidx;
|
|
unsigned char *pad;
|
|
uint8_t prot;
|
|
int error, maxpacketsize;
|
|
|
|
struct cryptodesc *crde = NULL, *crda = NULL;
|
|
struct cryptop *crp;
|
|
|
|
IPSEC_SPLASSERT_SOFTNET(__func__);
|
|
|
|
KASSERT(isr->sav != NULL);
|
|
sav = isr->sav;
|
|
esph = sav->tdb_authalgxform;
|
|
KASSERT(sav->tdb_encalgxform != NULL);
|
|
espx = sav->tdb_encalgxform;
|
|
|
|
if (sav->flags & SADB_X_EXT_OLD)
|
|
hlen = sizeof(struct esp) + sav->ivlen;
|
|
else
|
|
hlen = sizeof(struct newesp) + sav->ivlen;
|
|
|
|
rlen = m->m_pkthdr.len - skip; /* Raw payload length. */
|
|
/*
|
|
* NB: The null encoding transform has a blocksize of 4
|
|
* so that headers are properly aligned.
|
|
*/
|
|
blks = espx->blocksize; /* IV blocksize */
|
|
|
|
/* XXX clamp padding length a la KAME??? */
|
|
padding = ((blks - ((rlen + 2) % blks)) % blks) + 2;
|
|
|
|
if (esph)
|
|
alen = esph->authsize;
|
|
else
|
|
alen = 0;
|
|
|
|
ESP_STATINC(ESP_STAT_OUTPUT);
|
|
|
|
saidx = &sav->sah->saidx;
|
|
/* Check for maximum packet size violations. */
|
|
switch (saidx->dst.sa.sa_family) {
|
|
#ifdef INET
|
|
case AF_INET:
|
|
maxpacketsize = IP_MAXPACKET;
|
|
break;
|
|
#endif /* INET */
|
|
#ifdef INET6
|
|
case AF_INET6:
|
|
maxpacketsize = IPV6_MAXPACKET;
|
|
break;
|
|
#endif /* INET6 */
|
|
default:
|
|
DPRINTF(("%s: unknown/unsupported protocol family %d, "
|
|
"SA %s/%08lx\n", __func__, saidx->dst.sa.sa_family,
|
|
ipsec_address(&saidx->dst, buf, sizeof(buf)),
|
|
(u_long)ntohl(sav->spi)));
|
|
ESP_STATINC(ESP_STAT_NOPF);
|
|
error = EPFNOSUPPORT;
|
|
goto bad;
|
|
}
|
|
if (skip + hlen + rlen + padding + alen > maxpacketsize) {
|
|
DPRINTF(("%s: packet in SA %s/%08lx got too big (len %u, "
|
|
"max len %u)\n", __func__,
|
|
ipsec_address(&saidx->dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(sav->spi),
|
|
skip + hlen + rlen + padding + alen, maxpacketsize));
|
|
ESP_STATINC(ESP_STAT_TOOBIG);
|
|
error = EMSGSIZE;
|
|
goto bad;
|
|
}
|
|
|
|
/* Update the counters. */
|
|
ESP_STATADD(ESP_STAT_OBYTES, m->m_pkthdr.len - skip);
|
|
|
|
m = m_clone(m);
|
|
if (m == NULL) {
|
|
DPRINTF(("%s: cannot clone mbuf chain, SA %s/%08lx\n", __func__,
|
|
ipsec_address(&saidx->dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(sav->spi)));
|
|
ESP_STATINC(ESP_STAT_HDROPS);
|
|
error = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
|
|
/* Inject ESP header. */
|
|
mo = m_makespace(m, skip, hlen, &roff);
|
|
if (mo == NULL) {
|
|
DPRINTF(("%s: failed to inject %u byte ESP hdr for SA "
|
|
"%s/%08lx\n", __func__, hlen,
|
|
ipsec_address(&saidx->dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(sav->spi)));
|
|
ESP_STATINC(ESP_STAT_HDROPS); /* XXX diffs from openbsd */
|
|
error = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
|
|
/* Initialize ESP header. */
|
|
memcpy(mtod(mo, char *) + roff, &sav->spi, sizeof(uint32_t));
|
|
if (sav->replay) {
|
|
uint32_t replay;
|
|
|
|
#ifdef IPSEC_DEBUG
|
|
/* Emulate replay attack when ipsec_replay is TRUE. */
|
|
if (!ipsec_replay)
|
|
#endif
|
|
sav->replay->count++;
|
|
|
|
replay = htonl(sav->replay->count);
|
|
memcpy(mtod(mo,char *) + roff + sizeof(uint32_t), &replay,
|
|
sizeof(uint32_t));
|
|
}
|
|
|
|
/*
|
|
* Add padding -- better to do it ourselves than use the crypto engine,
|
|
* although if/when we support compression, we'd have to do that.
|
|
*/
|
|
pad = m_pad(m, padding + alen);
|
|
if (pad == NULL) {
|
|
DPRINTF(("%s: m_pad failed for SA %s/%08lx\n", __func__,
|
|
ipsec_address(&saidx->dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(sav->spi)));
|
|
m = NULL; /* NB: free'd by m_pad */
|
|
error = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
|
|
/*
|
|
* Add padding: random, zero, or self-describing.
|
|
* XXX catch unexpected setting
|
|
*/
|
|
switch (sav->flags & SADB_X_EXT_PMASK) {
|
|
case SADB_X_EXT_PRAND:
|
|
(void) cprng_fast(pad, padding - 2);
|
|
break;
|
|
case SADB_X_EXT_PZERO:
|
|
memset(pad, 0, padding - 2);
|
|
break;
|
|
case SADB_X_EXT_PSEQ:
|
|
for (i = 0; i < padding - 2; i++)
|
|
pad[i] = i+1;
|
|
break;
|
|
}
|
|
|
|
/* Fix padding length and Next Protocol in padding itself. */
|
|
pad[padding - 2] = padding - 2;
|
|
m_copydata(m, protoff, sizeof(uint8_t), pad + padding - 1);
|
|
|
|
/* Fix Next Protocol in IPv4/IPv6 header. */
|
|
prot = IPPROTO_ESP;
|
|
m_copyback(m, protoff, sizeof(uint8_t), &prot);
|
|
|
|
/* Get crypto descriptors. */
|
|
crp = crypto_getreq(esph && espx ? 2 : 1);
|
|
if (crp == NULL) {
|
|
DPRINTF(("%s: failed to acquire crypto descriptors\n",
|
|
__func__));
|
|
ESP_STATINC(ESP_STAT_CRYPTO);
|
|
error = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
|
|
if (espx) {
|
|
crde = crp->crp_desc;
|
|
crda = crde->crd_next;
|
|
|
|
/* Encryption descriptor. */
|
|
crde->crd_skip = skip + hlen;
|
|
if (espx->type == CRYPTO_AES_GMAC)
|
|
crde->crd_len = 0;
|
|
else
|
|
crde->crd_len = m->m_pkthdr.len - (skip + hlen + alen);
|
|
crde->crd_flags = CRD_F_ENCRYPT;
|
|
crde->crd_inject = skip + hlen - sav->ivlen;
|
|
|
|
/* Encryption operation. */
|
|
crde->crd_alg = espx->type;
|
|
crde->crd_key = _KEYBUF(sav->key_enc);
|
|
crde->crd_klen = _KEYBITS(sav->key_enc);
|
|
/* XXX Rounds ? */
|
|
} else
|
|
crda = crp->crp_desc;
|
|
|
|
/* IPsec-specific opaque crypto info. */
|
|
tc = malloc(sizeof(*tc), M_XDATA, M_NOWAIT|M_ZERO);
|
|
if (tc == NULL) {
|
|
crypto_freereq(crp);
|
|
DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
|
|
ESP_STATINC(ESP_STAT_CRYPTO);
|
|
error = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
|
|
/* Callback parameters */
|
|
tc->tc_isr = isr;
|
|
tc->tc_spi = sav->spi;
|
|
tc->tc_dst = saidx->dst;
|
|
tc->tc_proto = saidx->proto;
|
|
|
|
/* Crypto operation descriptor. */
|
|
crp->crp_ilen = m->m_pkthdr.len; /* Total input length. */
|
|
crp->crp_flags = CRYPTO_F_IMBUF;
|
|
crp->crp_buf = m;
|
|
crp->crp_callback = esp_output_cb;
|
|
crp->crp_opaque = tc;
|
|
crp->crp_sid = sav->tdb_cryptoid;
|
|
|
|
if (esph) {
|
|
/* Authentication descriptor. */
|
|
crda->crd_skip = skip;
|
|
if (espx && espx->type == CRYPTO_AES_GCM_16)
|
|
crda->crd_len = hlen - sav->ivlen;
|
|
else
|
|
crda->crd_len = m->m_pkthdr.len - (skip + alen);
|
|
crda->crd_inject = m->m_pkthdr.len - alen;
|
|
|
|
/* Authentication operation. */
|
|
crda->crd_alg = esph->type;
|
|
if (espx && (espx->type == CRYPTO_AES_GCM_16 ||
|
|
espx->type == CRYPTO_AES_GMAC)) {
|
|
crda->crd_key = _KEYBUF(sav->key_enc);
|
|
crda->crd_klen = _KEYBITS(sav->key_enc);
|
|
} else {
|
|
crda->crd_key = _KEYBUF(sav->key_auth);
|
|
crda->crd_klen = _KEYBITS(sav->key_auth);
|
|
}
|
|
}
|
|
|
|
return crypto_dispatch(crp);
|
|
bad:
|
|
if (m)
|
|
m_freem(m);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* ESP output callback from the crypto driver.
|
|
*/
|
|
static int
|
|
esp_output_cb(struct cryptop *crp)
|
|
{
|
|
struct tdb_crypto *tc;
|
|
struct ipsecrequest *isr;
|
|
struct secasvar *sav;
|
|
struct mbuf *m;
|
|
int s, err, error;
|
|
|
|
KASSERT(crp->crp_opaque != NULL);
|
|
tc = crp->crp_opaque;
|
|
m = crp->crp_buf;
|
|
|
|
s = splsoftnet();
|
|
mutex_enter(softnet_lock);
|
|
|
|
isr = tc->tc_isr;
|
|
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, 0, 0);
|
|
if (sav == NULL) {
|
|
char buf[IPSEC_ADDRSTRLEN];
|
|
ESP_STATINC(ESP_STAT_NOTDB);
|
|
DPRINTF(("%s: SA expired while in crypto (SA %s/%08lx "
|
|
"proto %u)\n", __func__,
|
|
ipsec_address(&tc->tc_dst, buf, sizeof(buf)),
|
|
(u_long) ntohl(tc->tc_spi), tc->tc_proto));
|
|
error = ENOBUFS; /*XXX*/
|
|
goto bad;
|
|
}
|
|
KASSERTMSG(isr->sav == sav,
|
|
"SA changed was %p now %p", isr->sav, sav);
|
|
|
|
/* Check for crypto errors. */
|
|
if (crp->crp_etype) {
|
|
/* Reset session ID. */
|
|
if (sav->tdb_cryptoid != 0)
|
|
sav->tdb_cryptoid = crp->crp_sid;
|
|
|
|
if (crp->crp_etype == EAGAIN) {
|
|
KEY_FREESAV(&sav);
|
|
mutex_exit(softnet_lock);
|
|
splx(s);
|
|
return crypto_dispatch(crp);
|
|
}
|
|
|
|
ESP_STATINC(ESP_STAT_NOXFORM);
|
|
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
|
|
error = crp->crp_etype;
|
|
goto bad;
|
|
}
|
|
|
|
/* Shouldn't happen... */
|
|
if (m == NULL) {
|
|
ESP_STATINC(ESP_STAT_CRYPTO);
|
|
DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
ESP_STATINC(ESP_STAT_HIST + esp_stats[sav->alg_enc]);
|
|
if (sav->tdb_authalgxform != NULL)
|
|
AH_STATINC(AH_STAT_HIST + ah_stats[sav->alg_auth]);
|
|
|
|
/* Release crypto descriptors. */
|
|
free(tc, M_XDATA);
|
|
crypto_freereq(crp);
|
|
|
|
#ifdef IPSEC_DEBUG
|
|
/* Emulate man-in-the-middle attack when ipsec_integrity is TRUE. */
|
|
if (ipsec_integrity) {
|
|
static unsigned char ipseczeroes[AH_ALEN_MAX];
|
|
const struct auth_hash *esph;
|
|
|
|
/*
|
|
* Corrupt HMAC if we want to test integrity verification of
|
|
* the other side.
|
|
*/
|
|
esph = sav->tdb_authalgxform;
|
|
if (esph != NULL) {
|
|
m_copyback(m, m->m_pkthdr.len - esph->authsize,
|
|
esph->authsize, ipseczeroes);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* NB: m is reclaimed by ipsec_process_done. */
|
|
err = ipsec_process_done(m, isr);
|
|
KEY_FREESAV(&sav);
|
|
mutex_exit(softnet_lock);
|
|
splx(s);
|
|
return err;
|
|
bad:
|
|
if (sav)
|
|
KEY_FREESAV(&sav);
|
|
mutex_exit(softnet_lock);
|
|
splx(s);
|
|
if (m)
|
|
m_freem(m);
|
|
free(tc, M_XDATA);
|
|
crypto_freereq(crp);
|
|
return error;
|
|
}
|
|
|
|
static struct xformsw esp_xformsw = {
|
|
.xf_type = XF_ESP,
|
|
.xf_flags = XFT_CONF|XFT_AUTH,
|
|
.xf_name = "IPsec ESP",
|
|
.xf_init = esp_init,
|
|
.xf_zeroize = esp_zeroize,
|
|
.xf_input = esp_input,
|
|
.xf_output = esp_output,
|
|
.xf_next = NULL,
|
|
};
|
|
|
|
void
|
|
esp_attach(void)
|
|
{
|
|
|
|
espstat_percpu = percpu_alloc(sizeof(uint64_t) * ESP_NSTATS);
|
|
|
|
#define MAXIV(xform) \
|
|
if (xform.ivsize > esp_max_ivlen) \
|
|
esp_max_ivlen = xform.ivsize \
|
|
|
|
esp_max_ivlen = 0;
|
|
MAXIV(enc_xform_des); /* SADB_EALG_DESCBC */
|
|
MAXIV(enc_xform_3des); /* SADB_EALG_3DESCBC */
|
|
MAXIV(enc_xform_rijndael128); /* SADB_X_EALG_AES */
|
|
MAXIV(enc_xform_blf); /* SADB_X_EALG_BLOWFISHCBC */
|
|
MAXIV(enc_xform_cast5); /* SADB_X_EALG_CAST128CBC */
|
|
MAXIV(enc_xform_skipjack); /* SADB_X_EALG_SKIPJACK */
|
|
MAXIV(enc_xform_camellia); /* SADB_X_EALG_CAMELLIACBC */
|
|
MAXIV(enc_xform_aes_ctr); /* SADB_X_EALG_AESCTR */
|
|
MAXIV(enc_xform_null); /* SADB_EALG_NULL */
|
|
|
|
xform_register(&esp_xformsw);
|
|
#undef MAXIV
|
|
}
|