78a6b08618
Mainly focus on files that use BSD 2-Clause license, however the tool I was using misidentified many licenses so this was mostly a manual - error prone - task. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts. No functional change intended.
518 lines
15 KiB
C
518 lines
15 KiB
C
/*-
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* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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*
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* Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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/*
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* IEEE 802.11 WEP crypto support.
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*/
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#include "opt_wlan.h"
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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/malloc.h>
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#include <sys/kernel.h>
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#include <sys/module.h>
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#include <sys/endian.h>
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#include <sys/socket.h>
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#include <net/if.h>
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#include <net/if_media.h>
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#include <net/ethernet.h>
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#include <net80211/ieee80211_var.h>
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static void *wep_attach(struct ieee80211vap *, struct ieee80211_key *);
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static void wep_detach(struct ieee80211_key *);
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static int wep_setkey(struct ieee80211_key *);
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static void wep_setiv(struct ieee80211_key *, uint8_t *);
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static int wep_encap(struct ieee80211_key *, struct mbuf *);
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static int wep_decap(struct ieee80211_key *, struct mbuf *, int);
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static int wep_enmic(struct ieee80211_key *, struct mbuf *, int);
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static int wep_demic(struct ieee80211_key *, struct mbuf *, int);
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static const struct ieee80211_cipher wep = {
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.ic_name = "WEP",
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.ic_cipher = IEEE80211_CIPHER_WEP,
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.ic_header = IEEE80211_WEP_IVLEN + IEEE80211_WEP_KIDLEN,
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.ic_trailer = IEEE80211_WEP_CRCLEN,
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.ic_miclen = 0,
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.ic_attach = wep_attach,
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.ic_detach = wep_detach,
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.ic_setkey = wep_setkey,
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.ic_setiv = wep_setiv,
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.ic_encap = wep_encap,
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.ic_decap = wep_decap,
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.ic_enmic = wep_enmic,
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.ic_demic = wep_demic,
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};
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static int wep_encrypt(struct ieee80211_key *, struct mbuf *, int hdrlen);
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static int wep_decrypt(struct ieee80211_key *, struct mbuf *, int hdrlen);
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struct wep_ctx {
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struct ieee80211vap *wc_vap; /* for diagnostics+statistics */
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struct ieee80211com *wc_ic;
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uint32_t wc_iv; /* initial vector for crypto */
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};
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/* number of references from net80211 layer */
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static int nrefs = 0;
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static void *
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wep_attach(struct ieee80211vap *vap, struct ieee80211_key *k)
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{
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struct wep_ctx *ctx;
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ctx = (struct wep_ctx *) IEEE80211_MALLOC(sizeof(struct wep_ctx),
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M_80211_CRYPTO, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO);
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if (ctx == NULL) {
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vap->iv_stats.is_crypto_nomem++;
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return NULL;
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}
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ctx->wc_vap = vap;
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ctx->wc_ic = vap->iv_ic;
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get_random_bytes(&ctx->wc_iv, sizeof(ctx->wc_iv));
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nrefs++; /* NB: we assume caller locking */
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return ctx;
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}
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static void
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wep_detach(struct ieee80211_key *k)
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{
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struct wep_ctx *ctx = k->wk_private;
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IEEE80211_FREE(ctx, M_80211_CRYPTO);
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KASSERT(nrefs > 0, ("imbalanced attach/detach"));
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nrefs--; /* NB: we assume caller locking */
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}
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static int
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wep_setkey(struct ieee80211_key *k)
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{
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return k->wk_keylen >= 40/NBBY;
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}
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static void
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wep_setiv(struct ieee80211_key *k, uint8_t *ivp)
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{
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struct wep_ctx *ctx = k->wk_private;
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struct ieee80211vap *vap = ctx->wc_vap;
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uint32_t iv;
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uint8_t keyid;
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keyid = ieee80211_crypto_get_keyid(vap, k) << 6;
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/*
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* XXX
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* IV must not duplicate during the lifetime of the key.
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* But no mechanism to renew keys is defined in IEEE 802.11
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* for WEP. And the IV may be duplicated at other stations
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* because the session key itself is shared. So we use a
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* pseudo random IV for now, though it is not the right way.
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*
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* NB: Rather than use a strictly random IV we select a
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* random one to start and then increment the value for
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* each frame. This is an explicit tradeoff between
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* overhead and security. Given the basic insecurity of
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* WEP this seems worthwhile.
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*/
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/*
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* Skip 'bad' IVs from Fluhrer/Mantin/Shamir:
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* (B, 255, N) with 3 <= B < 16 and 0 <= N <= 255
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*/
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iv = ctx->wc_iv;
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if ((iv & 0xff00) == 0xff00) {
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int B = (iv & 0xff0000) >> 16;
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if (3 <= B && B < 16)
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iv += 0x0100;
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}
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ctx->wc_iv = iv + 1;
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/*
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* NB: Preserve byte order of IV for packet
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* sniffers; it doesn't matter otherwise.
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*/
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#if _BYTE_ORDER == _BIG_ENDIAN
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ivp[0] = iv >> 0;
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ivp[1] = iv >> 8;
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ivp[2] = iv >> 16;
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#else
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ivp[2] = iv >> 0;
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ivp[1] = iv >> 8;
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ivp[0] = iv >> 16;
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#endif
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ivp[3] = keyid;
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}
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/*
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* Add privacy headers appropriate for the specified key.
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*/
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static int
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wep_encap(struct ieee80211_key *k, struct mbuf *m)
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{
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struct wep_ctx *ctx = k->wk_private;
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struct ieee80211com *ic = ctx->wc_ic;
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struct ieee80211_frame *wh;
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uint8_t *ivp;
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int hdrlen;
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int is_mgmt;
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hdrlen = ieee80211_hdrspace(ic, mtod(m, void *));
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wh = mtod(m, struct ieee80211_frame *);
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is_mgmt = IEEE80211_IS_MGMT(wh);
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/*
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* Check to see if IV is required.
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*/
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if (is_mgmt && (k->wk_flags & IEEE80211_KEY_NOIVMGT))
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return 1;
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if ((! is_mgmt) && (k->wk_flags & IEEE80211_KEY_NOIV))
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return 1;
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/*
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* Copy down 802.11 header and add the IV + KeyID.
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*/
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M_PREPEND(m, wep.ic_header, M_NOWAIT);
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if (m == NULL)
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return 0;
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ivp = mtod(m, uint8_t *);
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ovbcopy(ivp + wep.ic_header, ivp, hdrlen);
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ivp += hdrlen;
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wep_setiv(k, ivp);
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/*
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* Finally, do software encrypt if needed.
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*/
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if ((k->wk_flags & IEEE80211_KEY_SWENCRYPT) &&
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!wep_encrypt(k, m, hdrlen))
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return 0;
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return 1;
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}
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/*
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* Add MIC to the frame as needed.
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*/
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static int
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wep_enmic(struct ieee80211_key *k, struct mbuf *m, int force)
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{
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return 1;
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}
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/*
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* Validate and strip privacy headers (and trailer) for a
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* received frame. If necessary, decrypt the frame using
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* the specified key.
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*/
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static int
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wep_decap(struct ieee80211_key *k, struct mbuf *m, int hdrlen)
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{
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struct wep_ctx *ctx = k->wk_private;
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struct ieee80211vap *vap = ctx->wc_vap;
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struct ieee80211_frame *wh;
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const struct ieee80211_rx_stats *rxs;
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wh = mtod(m, struct ieee80211_frame *);
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rxs = ieee80211_get_rx_params_ptr(m);
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if ((rxs != NULL) && (rxs->c_pktflags & IEEE80211_RX_F_IV_STRIP))
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goto finish;
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/*
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* Check if the device handled the decrypt in hardware.
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* If so we just strip the header; otherwise we need to
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* handle the decrypt in software.
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*/
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if ((k->wk_flags & IEEE80211_KEY_SWDECRYPT) &&
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!wep_decrypt(k, m, hdrlen)) {
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IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO, wh->i_addr2,
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"%s", "WEP ICV mismatch on decrypt");
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vap->iv_stats.is_rx_wepfail++;
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return 0;
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}
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/*
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* Copy up 802.11 header and strip crypto bits.
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*/
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ovbcopy(mtod(m, void *), mtod(m, uint8_t *) + wep.ic_header, hdrlen);
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m_adj(m, wep.ic_header);
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finish:
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/* XXX TODO: do we have to strip this for offload devices? */
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m_adj(m, -wep.ic_trailer);
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return 1;
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}
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/*
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* Verify and strip MIC from the frame.
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*/
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static int
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wep_demic(struct ieee80211_key *k, struct mbuf *skb, int force)
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{
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return 1;
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}
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static const uint32_t crc32_table[256] = {
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0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
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0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
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0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
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0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
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0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
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0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
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0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
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0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
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0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
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0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
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0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
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0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
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0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
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0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
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0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
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0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
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0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
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0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
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0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
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0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
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0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
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0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
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0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
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0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
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0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
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0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
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0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
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0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
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0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
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0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
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0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
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0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
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0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
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0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
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0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
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0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
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0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
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0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
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0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
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0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
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0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
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0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
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0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
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0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
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0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
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0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
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0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
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0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
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0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
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0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
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0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
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0x2d02ef8dL
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};
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static int
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wep_encrypt(struct ieee80211_key *key, struct mbuf *m0, int hdrlen)
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{
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#define S_SWAP(a,b) do { uint8_t t = S[a]; S[a] = S[b]; S[b] = t; } while(0)
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struct wep_ctx *ctx = key->wk_private;
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struct ieee80211vap *vap = ctx->wc_vap;
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struct mbuf *m = m0;
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uint8_t rc4key[IEEE80211_WEP_IVLEN + IEEE80211_KEYBUF_SIZE];
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uint8_t icv[IEEE80211_WEP_CRCLEN];
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uint32_t i, j, k, crc;
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size_t buflen, data_len;
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uint8_t S[256];
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uint8_t *pos;
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u_int off, keylen;
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vap->iv_stats.is_crypto_wep++;
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/* NB: this assumes the header was pulled up */
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memcpy(rc4key, mtod(m, uint8_t *) + hdrlen, IEEE80211_WEP_IVLEN);
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memcpy(rc4key + IEEE80211_WEP_IVLEN, key->wk_key, key->wk_keylen);
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/* Setup RC4 state */
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for (i = 0; i < 256; i++)
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S[i] = i;
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j = 0;
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keylen = key->wk_keylen + IEEE80211_WEP_IVLEN;
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for (i = 0; i < 256; i++) {
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j = (j + S[i] + rc4key[i % keylen]) & 0xff;
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S_SWAP(i, j);
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}
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off = hdrlen + wep.ic_header;
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data_len = m->m_pkthdr.len - off;
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/* Compute CRC32 over unencrypted data and apply RC4 to data */
|
|
crc = ~0;
|
|
i = j = 0;
|
|
pos = mtod(m, uint8_t *) + off;
|
|
buflen = m->m_len - off;
|
|
for (;;) {
|
|
if (buflen > data_len)
|
|
buflen = data_len;
|
|
data_len -= buflen;
|
|
for (k = 0; k < buflen; k++) {
|
|
crc = crc32_table[(crc ^ *pos) & 0xff] ^ (crc >> 8);
|
|
i = (i + 1) & 0xff;
|
|
j = (j + S[i]) & 0xff;
|
|
S_SWAP(i, j);
|
|
*pos++ ^= S[(S[i] + S[j]) & 0xff];
|
|
}
|
|
if (m->m_next == NULL) {
|
|
if (data_len != 0) { /* out of data */
|
|
IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO,
|
|
ether_sprintf(mtod(m0,
|
|
struct ieee80211_frame *)->i_addr2),
|
|
"out of data for WEP (data_len %zu)",
|
|
data_len);
|
|
/* XXX stat */
|
|
return 0;
|
|
}
|
|
break;
|
|
}
|
|
m = m->m_next;
|
|
pos = mtod(m, uint8_t *);
|
|
buflen = m->m_len;
|
|
}
|
|
crc = ~crc;
|
|
|
|
/* Append little-endian CRC32 and encrypt it to produce ICV */
|
|
icv[0] = crc;
|
|
icv[1] = crc >> 8;
|
|
icv[2] = crc >> 16;
|
|
icv[3] = crc >> 24;
|
|
for (k = 0; k < IEEE80211_WEP_CRCLEN; k++) {
|
|
i = (i + 1) & 0xff;
|
|
j = (j + S[i]) & 0xff;
|
|
S_SWAP(i, j);
|
|
icv[k] ^= S[(S[i] + S[j]) & 0xff];
|
|
}
|
|
return m_append(m0, IEEE80211_WEP_CRCLEN, icv);
|
|
#undef S_SWAP
|
|
}
|
|
|
|
static int
|
|
wep_decrypt(struct ieee80211_key *key, struct mbuf *m0, int hdrlen)
|
|
{
|
|
#define S_SWAP(a,b) do { uint8_t t = S[a]; S[a] = S[b]; S[b] = t; } while(0)
|
|
struct wep_ctx *ctx = key->wk_private;
|
|
struct ieee80211vap *vap = ctx->wc_vap;
|
|
struct mbuf *m = m0;
|
|
uint8_t rc4key[IEEE80211_WEP_IVLEN + IEEE80211_KEYBUF_SIZE];
|
|
uint8_t icv[IEEE80211_WEP_CRCLEN];
|
|
uint32_t i, j, k, crc;
|
|
size_t buflen, data_len;
|
|
uint8_t S[256];
|
|
uint8_t *pos;
|
|
u_int off, keylen;
|
|
|
|
vap->iv_stats.is_crypto_wep++;
|
|
|
|
/* NB: this assumes the header was pulled up */
|
|
memcpy(rc4key, mtod(m, uint8_t *) + hdrlen, IEEE80211_WEP_IVLEN);
|
|
memcpy(rc4key + IEEE80211_WEP_IVLEN, key->wk_key, key->wk_keylen);
|
|
|
|
/* Setup RC4 state */
|
|
for (i = 0; i < 256; i++)
|
|
S[i] = i;
|
|
j = 0;
|
|
keylen = key->wk_keylen + IEEE80211_WEP_IVLEN;
|
|
for (i = 0; i < 256; i++) {
|
|
j = (j + S[i] + rc4key[i % keylen]) & 0xff;
|
|
S_SWAP(i, j);
|
|
}
|
|
|
|
off = hdrlen + wep.ic_header;
|
|
data_len = m->m_pkthdr.len - (off + wep.ic_trailer);
|
|
|
|
/* Compute CRC32 over unencrypted data and apply RC4 to data */
|
|
crc = ~0;
|
|
i = j = 0;
|
|
pos = mtod(m, uint8_t *) + off;
|
|
buflen = m->m_len - off;
|
|
for (;;) {
|
|
if (buflen > data_len)
|
|
buflen = data_len;
|
|
data_len -= buflen;
|
|
for (k = 0; k < buflen; k++) {
|
|
i = (i + 1) & 0xff;
|
|
j = (j + S[i]) & 0xff;
|
|
S_SWAP(i, j);
|
|
*pos ^= S[(S[i] + S[j]) & 0xff];
|
|
crc = crc32_table[(crc ^ *pos) & 0xff] ^ (crc >> 8);
|
|
pos++;
|
|
}
|
|
m = m->m_next;
|
|
if (m == NULL) {
|
|
if (data_len != 0) { /* out of data */
|
|
IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO,
|
|
mtod(m0, struct ieee80211_frame *)->i_addr2,
|
|
"out of data for WEP (data_len %zu)",
|
|
data_len);
|
|
return 0;
|
|
}
|
|
break;
|
|
}
|
|
pos = mtod(m, uint8_t *);
|
|
buflen = m->m_len;
|
|
}
|
|
crc = ~crc;
|
|
|
|
/* Encrypt little-endian CRC32 and verify that it matches with
|
|
* received ICV */
|
|
icv[0] = crc;
|
|
icv[1] = crc >> 8;
|
|
icv[2] = crc >> 16;
|
|
icv[3] = crc >> 24;
|
|
for (k = 0; k < IEEE80211_WEP_CRCLEN; k++) {
|
|
i = (i + 1) & 0xff;
|
|
j = (j + S[i]) & 0xff;
|
|
S_SWAP(i, j);
|
|
/* XXX assumes ICV is contiguous in mbuf */
|
|
if ((icv[k] ^ S[(S[i] + S[j]) & 0xff]) != *pos++) {
|
|
/* ICV mismatch - drop frame */
|
|
return 0;
|
|
}
|
|
}
|
|
return 1;
|
|
#undef S_SWAP
|
|
}
|
|
|
|
/*
|
|
* Module glue.
|
|
*/
|
|
IEEE80211_CRYPTO_MODULE(wep, 1);
|