/* * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * Copyright (c) 2001 Atsushi Onoe * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting * 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. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ #pragma ident "%Z%%M% %I% %E% SMI" /* * IEEE 802.11 generic crypto support */ #include #include #include #include #include #include "net80211_impl.h" extern const struct ieee80211_cipher wep; extern const struct ieee80211_cipher tkip; extern const struct ieee80211_cipher ccmp; /* * Table of registered cipher modules. */ static const char *cipher_modnames[] = { "wlan_wep", /* IEEE80211_CIPHER_WEP */ "wlan_tkip", /* IEEE80211_CIPHER_TKIP */ "wlan_aes_ocb", /* IEEE80211_CIPHER_AES_OCB */ "wlan_ccmp", /* IEEE80211_CIPHER_AES_CCM */ "wlan_ckip", /* IEEE80211_CIPHER_CKIP */ }; /* * Default "null" key management routines. */ /* ARGSUSED */ static int nulldev_key_alloc(ieee80211com_t *ic, const struct ieee80211_key *k, ieee80211_keyix *keyix, ieee80211_keyix *rxkeyix) { *keyix = 0; /* use key index 0 for ucast key */ *rxkeyix = IEEE80211_KEYIX_NONE; return (1); } /* ARGSUSED */ static int nulldev_key_delete(ieee80211com_t *ic, const struct ieee80211_key *k) { return (1); } /* ARGSUSED */ static int nulldev_key_set(ieee80211com_t *ic, const struct ieee80211_key *k, const uint8_t *mac) { return (1); } /* ARGSUSED */ static void nulldev_key_update(ieee80211com_t *ic) { /* noop */ } /* * Reset key state to an unused state. The crypto * key allocation mechanism insures other state (e.g. * key data) is properly setup before a key is used. */ void ieee80211_crypto_resetkey(ieee80211com_t *ic, struct ieee80211_key *k, ieee80211_keyix ix) { k->wk_cipher = &ieee80211_cipher_none; k->wk_private = k->wk_cipher->ic_attach(ic, k); k->wk_keyix = ix; k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV; } /* * Establish a relationship between the specified key and cipher * and, if necessary, allocate a hardware index from the driver. * Note that when a fixed key index is required it must be specified * and we blindly assign it w/o consulting the driver. * * This must be the first call applied to a key; all the other key * routines assume wk_cipher is setup. * * Locking must be handled by the caller using: * ieee80211_key_update_begin(ic); * ieee80211_key_update_end(ic); */ int ieee80211_crypto_newkey(ieee80211com_t *ic, int cipher, int flags, struct ieee80211_key *key) { const struct ieee80211_cipher *cip; ieee80211_keyix keyix, rxkeyix; void *keyctx; uint16_t oflags; /* * Validate cipher and set reference to cipher routines. */ if (cipher >= IEEE80211_CIPHER_MAX) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_newkey: " "invalid cipher %u\n", cipher); return (0); } cip = ic->ic_ciphers[cipher]; /* already load all the ciphers, cip can't be NULL */ if (cip == NULL) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_newkey: " "unable to load cipher %u, module %s\n", cipher, cipher < IEEE80211_N(cipher_modnames) ? cipher_modnames[cipher] : ""); return (0); } oflags = key->wk_flags; flags &= IEEE80211_KEY_COMMON; /* * If the hardware does not support the cipher then * fallback to a host-based implementation. */ if ((ic->ic_caps & (1<ic_name); flags |= IEEE80211_KEY_SWCRYPT; } /* * Hardware TKIP with software MIC is an important * combination; we handle it by flagging each key, * the cipher modules honor it. */ if (cipher == IEEE80211_CIPHER_TKIP && (ic->ic_caps & IEEE80211_C_TKIPMIC) == 0) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "no h/w support for TKIP MIC, falling back to s/w\n"); flags |= IEEE80211_KEY_SWMIC; } /* * Bind cipher to key instance. Note we do this * after checking the device capabilities so the * cipher module can optimize space usage based on * whether or not it needs to do the cipher work. */ if (key->wk_cipher != cip || key->wk_flags != flags) { again: /* * Fillin the flags so cipher modules can see s/w * crypto requirements and potentially allocate * different state and/or attach different method * pointers. */ key->wk_flags = (uint16_t)flags; keyctx = cip->ic_attach(ic, key); if (keyctx == NULL) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "crypto_setkey: " "unable to attach cipher %s\n", cip->ic_name); key->wk_flags = oflags; /* restore old flags */ return (0); } CIPHER_DETACH(key); /* Detach old cipher */ key->wk_cipher = cip; key->wk_private = keyctx; } /* * Commit to requested usage so driver can see the flags. */ key->wk_flags = (uint16_t)flags; /* * Ask the driver for a key index if we don't have one. * Note that entries in the global key table always have * an index; this means it's safe to call this routine * for these entries just to setup the reference to the * cipher template. Note also that when using software * crypto we also call the driver to give us a key index. */ if (key->wk_keyix == IEEE80211_KEYIX_NONE) { if (!DEV_KEY_ALLOC(ic, key, &keyix, &rxkeyix)) { /* * Driver has no room; fallback to doing crypto * in the host. We change the flags and start the * procedure over. If we get back here then there's * no hope and we bail. Note that this can leave * the key in a inconsistent state if the caller * continues to use it. */ if ((key->wk_flags & IEEE80211_KEY_SWCRYPT) == 0) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "crypto_setkey: " "no h/w resources for cipher %s, " "falling back to s/w\n", cip->ic_name); oflags = key->wk_flags; flags |= IEEE80211_KEY_SWCRYPT; if (cipher == IEEE80211_CIPHER_TKIP) flags |= IEEE80211_KEY_SWMIC; goto again; } ieee80211_dbg(IEEE80211_MSG_CRYPTO, "crypto_setkey: " "unable to setup cipher %s\n", cip->ic_name); return (0); } key->wk_keyix = keyix; key->wk_rxkeyix = rxkeyix; } return (1); } /* * Remove the key (no locking, for internal use). */ static int ieee80211_crypto_delkey_locked(ieee80211com_t *ic, struct ieee80211_key *key) { uint16_t keyix; ASSERT(key->wk_cipher != NULL); keyix = key->wk_keyix; if (keyix != IEEE80211_KEYIX_NONE) { /* * Remove hardware entry. */ if (!DEV_KEY_DELETE(ic, key)) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_delkey_locked: ", "driverdeletes key %u failed\n", keyix); } } CIPHER_DETACH(key); bzero(key, sizeof (struct ieee80211_key)); /* NB: cannot depend on key index to decide this */ ieee80211_crypto_resetkey(ic, key, IEEE80211_KEYIX_NONE); return (1); } /* * Remove the specified key. */ int ieee80211_crypto_delkey(ieee80211com_t *ic, struct ieee80211_key *key) { int status; KEY_UPDATE_BEGIN(ic); status = ieee80211_crypto_delkey_locked(ic, key); KEY_UPDATE_END(ic); return (status); } /* * Clear the global key table. */ static void ieee80211_crypto_delglobalkeys(ieee80211com_t *ic) { int i; KEY_UPDATE_BEGIN(ic); for (i = 0; i < IEEE80211_WEP_NKID; i++) (void) ieee80211_crypto_delkey_locked(ic, &ic->ic_nw_keys[i]); KEY_UPDATE_END(ic); } /* * Set the contents of the specified key. * * Locking must be handled by the caller using: * ieee80211_key_update_begin(ic); * ieee80211_key_update_end(ic); */ int ieee80211_crypto_setkey(ieee80211com_t *ic, struct ieee80211_key *key, const uint8_t *macaddr) { const struct ieee80211_cipher *cip = key->wk_cipher; ASSERT(cip != NULL); ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_setkey: " "%s keyix %u flags 0x%x mac %s len %u\n", cip->ic_name, key->wk_keyix, key->wk_flags, ieee80211_macaddr_sprintf(macaddr), key->wk_keylen); /* * Give cipher a chance to validate key contents. * should happen before modifying state. */ if (cip->ic_setkey(key) == 0) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_setkey: " "cipher %s rejected key index %u len %u flags 0x%x\n", cip->ic_name, key->wk_keyix, key->wk_keylen, key->wk_flags); return (0); } if (key->wk_keyix == IEEE80211_KEYIX_NONE) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_setkey: " "no key index; should not happen!\n"); return (0); } return (DEV_KEY_SET(ic, key, macaddr)); } /* * Return the transmit key to use in sending a frame. */ struct ieee80211_key * ieee80211_crypto_getkey(ieee80211com_t *ic) { if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE || KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey])) return (NULL); return (&ic->ic_nw_keys[ic->ic_def_txkey]); } uint8_t ieee80211_crypto_getciphertype(ieee80211com_t *ic) { struct ieee80211_key *key; uint32_t cipher; static const uint8_t ciphermap[] = { WIFI_SEC_WEP, /* IEEE80211_CIPHER_WEP */ WIFI_SEC_WPA, /* IEEE80211_CIPHER_TKIP */ (uint8_t)-1, /* IEEE80211_CIPHER_AES_OCB */ WIFI_SEC_WPA, /* IEEE80211_CIPHER_AES_CCM */ (uint8_t)-1, /* IEEE80211_CIPHER_CKIP */ WIFI_SEC_NONE, /* IEEE80211_CIPHER_NONE */ }; if ((ic->ic_flags & IEEE80211_F_PRIVACY) == 0) return (WIFI_SEC_NONE); key = ieee80211_crypto_getkey(ic); if (key == NULL) return (WIFI_SEC_NONE); cipher = key->wk_cipher->ic_cipher; ASSERT(cipher < IEEE80211_N(ciphermap)); return (ciphermap[cipher]); } /* * Add privacy headers appropriate for the specified key. */ struct ieee80211_key * ieee80211_crypto_encap(ieee80211com_t *ic, mblk_t *mp) { struct ieee80211_key *k; const struct ieee80211_cipher *cip; uint8_t keyix; if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_encap: %s", " No default xmit key for frame\n"); return (NULL); } keyix = ic->ic_def_txkey; k = &ic->ic_nw_keys[ic->ic_def_txkey]; cip = k->wk_cipher; return (cip->ic_encap(k, mp, keyix<<6) ? k : NULL); } /* * Validate and strip privacy headers (and trailer) for a * received frame that has the WEP/Privacy bit set. */ struct ieee80211_key * ieee80211_crypto_decap(ieee80211com_t *ic, mblk_t *mp, int hdrlen) { struct ieee80211_key *k; const struct ieee80211_cipher *cip; uint8_t *ivp; uint8_t keyid; /* NB: this minimum size data frame could be bigger */ if (MBLKL(mp) < IEEE80211_WEP_MINLEN) { ieee80211_dbg(IEEE80211_MSG_CRYPTO, "ieee80211_crypto_decap:" " WEP data frame too short, len %u\n", MBLKL(mp)); return (NULL); } /* * Locate the key. If unicast and there is no unicast * key then we fall back to the key id in the header. * This assumes unicast keys are only configured when * the key id in the header is meaningless (typically 0). */ ivp = mp->b_rptr + hdrlen; keyid = ivp[IEEE80211_WEP_IVLEN]; k = &ic->ic_nw_keys[keyid >> 6]; /* check to avoid panic when wep is on but key is not set */ if (k->wk_cipher == &ieee80211_cipher_none || k->wk_cipher == NULL) return (NULL); cip = k->wk_cipher; return ((cip->ic_decap)(k, mp, hdrlen) ? k : NULL); } /* * Setup crypto support. */ void ieee80211_crypto_attach(ieee80211com_t *ic) { struct ieee80211_crypto_state *cs = &ic->ic_crypto; int i; (void) crypto_mech2id(SUN_CKM_RC4); /* Load RC4 */ (void) crypto_mech2id(SUN_CKM_AES_CBC); /* Load AES-CBC */ (void) crypto_mech2id(SUN_CKM_AES_CCM); /* Load AES-CCM */ /* NB: we assume everything is pre-zero'd */ cs->cs_def_txkey = IEEE80211_KEYIX_NONE; for (i = 0; i < IEEE80211_WEP_NKID; i++) { ieee80211_crypto_resetkey(ic, &cs->cs_nw_keys[i], IEEE80211_KEYIX_NONE); } /* * Initialize the driver key support routines to noop entries. * This is useful especially for the cipher test modules. */ cs->cs_key_alloc = nulldev_key_alloc; cs->cs_key_set = nulldev_key_set; cs->cs_key_delete = nulldev_key_delete; cs->cs_key_update_begin = nulldev_key_update; cs->cs_key_update_end = nulldev_key_update; ieee80211_crypto_register(ic, &wep); ieee80211_crypto_register(ic, &tkip); ieee80211_crypto_register(ic, &ccmp); } /* * Teardown crypto support. */ void ieee80211_crypto_detach(ieee80211com_t *ic) { ieee80211_crypto_delglobalkeys(ic); ieee80211_crypto_unregister(ic, &wep); ieee80211_crypto_unregister(ic, &tkip); ieee80211_crypto_unregister(ic, &ccmp); } /* * Register a crypto cipher module. */ void ieee80211_crypto_register(ieee80211com_t *ic, const struct ieee80211_cipher *cip) { if (cip->ic_cipher >= IEEE80211_CIPHER_MAX) { ieee80211_err("ieee80211_crypto_register: " "cipher %s has an invalid cipher index %u\n", cip->ic_name, cip->ic_cipher); return; } if (ic->ic_ciphers[cip->ic_cipher] != NULL && ic->ic_ciphers[cip->ic_cipher] != cip) { ieee80211_err("ieee80211_crypto_register: " "cipher %s registered with a different template\n", cip->ic_name); return; } ic->ic_ciphers[cip->ic_cipher] = cip; } /* * Unregister a crypto cipher module. */ void ieee80211_crypto_unregister(ieee80211com_t *ic, const struct ieee80211_cipher *cip) { if (cip->ic_cipher >= IEEE80211_CIPHER_MAX) { ieee80211_err("ieee80211_crypto_unregister: " "cipher %s has an invalid cipher index %u\n", cip->ic_name, cip->ic_cipher); return; } if (ic->ic_ciphers[cip->ic_cipher] != NULL && ic->ic_ciphers[cip->ic_cipher] != cip) { ieee80211_err("ieee80211_crypto_unregister: " "cipher %s registered with a different template\n", cip->ic_name); return; } /* NB: don't complain about not being registered */ ic->ic_ciphers[cip->ic_cipher] = NULL; }