| /*- |
| * 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. |
| * |
| * $Id: ieee80211_crypto_ccmp.c 2144 2007-02-21 20:58:48Z proski $ |
| */ |
| |
| /* |
| * IEEE 802.11i AES-CCMP crypto support. |
| * |
| * Part of this module is derived from similar code in the Host |
| * AP driver. The code is used with the consent of the author and |
| * it's license is included below. |
| */ |
| #ifndef AUTOCONF_INCLUDED |
| #include <linux/config.h> |
| #endif |
| #include <linux/version.h> |
| #include <linux/module.h> |
| #include <linux/skbuff.h> |
| #include <linux/netdevice.h> |
| #include <linux/random.h> |
| #include <linux/init.h> |
| |
| #include <linux/crypto.h> |
| #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,7,0) |
| #include <linux/scatterlist.h> |
| #else |
| #include <asm/scatterlist.h> |
| #endif |
| |
| #include "net80211/if_media.h" |
| |
| #include "net80211/ieee80211_var.h" |
| |
| #define AES_BLOCK_LEN 16 |
| |
| struct ccmp_ctx { |
| struct ieee80211vap *cc_vap; /* for diagnostics + statistics */ |
| struct ieee80211com *cc_ic; |
| struct crypto_cipher *cc_tfm; |
| }; |
| |
| static void *ccmp_attach(struct ieee80211vap *, struct ieee80211_key *); |
| static void ccmp_detach(struct ieee80211_key *); |
| static int ccmp_setkey(struct ieee80211_key *); |
| static int ccmp_encap(struct ieee80211_key *, struct sk_buff *, u_int8_t); |
| static int ccmp_decap(struct ieee80211_key *, struct sk_buff *, int); |
| static int ccmp_enmic(struct ieee80211_key *, struct sk_buff *, int); |
| static int ccmp_demic(struct ieee80211_key *, struct sk_buff *, int); |
| |
| static const struct ieee80211_cipher ccmp = { |
| .ic_name = "AES-CCM", |
| .ic_cipher = IEEE80211_CIPHER_AES_CCM, |
| .ic_header = IEEE80211_WEP_IVLEN + IEEE80211_WEP_KIDLEN + |
| IEEE80211_WEP_EXTIVLEN, |
| .ic_trailer = IEEE80211_WEP_MICLEN, |
| .ic_miclen = 0, |
| .ic_attach = ccmp_attach, |
| .ic_detach = ccmp_detach, |
| .ic_setkey = ccmp_setkey, |
| .ic_encap = ccmp_encap, |
| .ic_decap = ccmp_decap, |
| .ic_enmic = ccmp_enmic, |
| .ic_demic = ccmp_demic, |
| }; |
| |
| static int ccmp_encrypt(struct ieee80211_key *, struct sk_buff *, int); |
| static int ccmp_decrypt(struct ieee80211_key *, u_int64_t, struct sk_buff *, int); |
| |
| static void * |
| ccmp_attach(struct ieee80211vap *vap, struct ieee80211_key *k) |
| { |
| struct ccmp_ctx *ctx; |
| |
| _MOD_INC_USE(THIS_MODULE, return NULL); |
| |
| MALLOC(ctx, struct ccmp_ctx *, sizeof(struct ccmp_ctx), |
| M_DEVBUF, M_NOWAIT | M_ZERO); |
| if (ctx == NULL) { |
| vap->iv_stats.is_crypto_nomem++; |
| _MOD_DEC_USE(THIS_MODULE); |
| return NULL; |
| } |
| |
| ctx->cc_vap = vap; |
| ctx->cc_ic = vap->iv_ic; |
| return ctx; |
| } |
| |
| static void |
| ccmp_detach(struct ieee80211_key *k) |
| { |
| struct ccmp_ctx *ctx = k->wk_private; |
| |
| if (ctx->cc_tfm != NULL) |
| crypto_free_cipher(ctx->cc_tfm); |
| FREE(ctx, M_DEVBUF); |
| |
| _MOD_DEC_USE(THIS_MODULE); |
| } |
| |
| static int |
| ccmp_setkey(struct ieee80211_key *k) |
| { |
| struct ccmp_ctx *ctx = k->wk_private; |
| |
| if (k->wk_keylen != (128 / NBBY)) { |
| IEEE80211_DPRINTF(ctx->cc_vap, IEEE80211_MSG_CRYPTO, |
| "%s: Invalid key length %u, expecting %u\n", |
| __func__, k->wk_keylen, 128 / NBBY); |
| return 0; |
| } |
| |
| if (k->wk_flags & IEEE80211_KEY_SWCRYPT) { |
| if (ctx->cc_tfm == NULL) |
| ctx->cc_tfm = crypto_alloc_cipher("aes", 0, |
| CRYPTO_ALG_ASYNC); |
| |
| if (ctx->cc_tfm == NULL) { |
| IEEE80211_DPRINTF(ctx->cc_vap, IEEE80211_MSG_CRYPTO, |
| "%s: Tried to add a software crypto key, but software crypto not available\n", |
| __func__); |
| return 0; |
| } |
| |
| crypto_cipher_setkey(ctx->cc_tfm, k->wk_key, k->wk_keylen); |
| } |
| return 1; |
| } |
| |
| /* |
| * Add privacy headers appropriate for the specified key. |
| */ |
| static int |
| ccmp_encap(struct ieee80211_key *k, struct sk_buff *skb, u_int8_t keyid) |
| { |
| struct ccmp_ctx *ctx = k->wk_private; |
| struct ieee80211com *ic = ctx->cc_ic; |
| u_int8_t *ivp; |
| int hdrlen; |
| |
| hdrlen = ieee80211_hdrspace(ic, skb->data); |
| |
| /* |
| * Copy down 802.11 header and add the IV, KeyID, and ExtIV. |
| */ |
| ivp = skb_push(skb, ccmp.ic_header); |
| memmove(ivp, ivp + ccmp.ic_header, hdrlen); |
| ivp += hdrlen; |
| |
| k->wk_keytsc++; /* XXX wrap at 48 bits */ |
| ivp[0] = k->wk_keytsc >> 0; /* PN0 */ |
| ivp[1] = k->wk_keytsc >> 8; /* PN1 */ |
| ivp[2] = 0; /* Reserved */ |
| ivp[3] = keyid | IEEE80211_WEP_EXTIV; /* KeyID | ExtID */ |
| ivp[4] = k->wk_keytsc >> 16; /* PN2 */ |
| ivp[5] = k->wk_keytsc >> 24; /* PN3 */ |
| ivp[6] = k->wk_keytsc >> 32; /* PN4 */ |
| ivp[7] = k->wk_keytsc >> 40; /* PN5 */ |
| |
| /* |
| * Finally, do software encrypt if neeed. |
| */ |
| if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) && |
| !ccmp_encrypt(k, skb, hdrlen)) |
| return 0; |
| |
| return 1; |
| } |
| |
| /* |
| * Add MIC to the frame as needed. |
| */ |
| static int |
| ccmp_enmic(struct ieee80211_key *k, struct sk_buff *skb, int force) |
| { |
| return 1; |
| } |
| |
| static __inline uint64_t |
| READ_6(uint8_t b0, uint8_t b1, uint8_t b2, uint8_t b3, uint8_t b4, uint8_t b5) |
| { |
| uint32_t iv32 = (b0 << 0) | (b1 << 8) | (b2 << 16) | (b3 << 24); |
| uint16_t iv16 = (b4 << 0) | (b5 << 8); |
| return (((uint64_t)iv16) << 32) | iv32; |
| } |
| |
| /* |
| * Validate and strip privacy headers (and trailer) for a |
| * received frame. The specified key should be correct but |
| * is also verified. |
| */ |
| static int |
| ccmp_decap(struct ieee80211_key *k, struct sk_buff *skb, int hdrlen) |
| { |
| struct ccmp_ctx *ctx = k->wk_private; |
| struct ieee80211vap *vap = ctx->cc_vap; |
| struct ieee80211_frame *wh; |
| uint8_t *ivp; |
| uint64_t pn; |
| u_int8_t tid; |
| |
| /* |
| * Header should have extended IV and sequence number; |
| * verify the former and validate the latter. |
| */ |
| wh = (struct ieee80211_frame *)skb->data; |
| ivp = skb->data + hdrlen; |
| if ((ivp[IEEE80211_WEP_IVLEN] & IEEE80211_WEP_EXTIV) == 0) { |
| /* |
| * No extended IV; discard frame. |
| */ |
| IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO, wh->i_addr2, |
| "%s", "Missing ExtIV for AES-CCM cipher"); |
| vap->iv_stats.is_rx_ccmpformat++; |
| return 0; |
| } |
| tid = 0; |
| if (IEEE80211_QOS_HAS_SEQ(wh)) |
| tid = ((struct ieee80211_qosframe *)wh)->i_qos[0] & IEEE80211_QOS_TID; |
| /* NB: assume IEEE80211_WEP_MINLEN covers the extended IV */ |
| pn = READ_6(ivp[0], ivp[1], ivp[4], ivp[5], ivp[6], ivp[7]); |
| if (pn <= k->wk_keyrsc[tid]) { |
| /* |
| * Replay violation. |
| */ |
| ieee80211_notify_replay_failure(vap, wh, k, pn); |
| vap->iv_stats.is_rx_ccmpreplay++; |
| return 0; |
| } |
| |
| /* |
| * Check if the device handled the decrypt in hardware. |
| * If so we just strip the header; otherwise we need to |
| * handle the decrypt in software. Note that for the |
| * latter we leave the header in place for use in the |
| * decryption work. |
| */ |
| if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) && |
| !ccmp_decrypt(k, pn, skb, hdrlen)) |
| return 0; |
| |
| /* |
| * Copy up 802.11 header and strip crypto bits. |
| */ |
| memmove(skb->data + ccmp.ic_header, skb->data, hdrlen); |
| skb_pull(skb, ccmp.ic_header); |
| while (skb->next != NULL) |
| skb = skb->next; |
| skb_trim(skb, skb->len - ccmp.ic_trailer); |
| |
| /* |
| * Ok to update rsc now. |
| */ |
| k->wk_keyrsc[tid] = pn; |
| |
| return 1; |
| } |
| |
| /* |
| * Verify and strip MIC from the frame. |
| */ |
| static int |
| ccmp_demic(struct ieee80211_key *k, struct sk_buff *skb, int hdrlen) |
| { |
| return 1; |
| } |
| |
| static __inline void |
| xor_block(u8 *b, const u8 *a, size_t len) |
| { |
| int i; |
| for (i = 0; i < len; i++) |
| b[i] ^= a[i]; |
| } |
| |
| static void |
| rijndael_encrypt(struct crypto_cipher *tfm, const void *src, void *dst) |
| { |
| crypto_cipher_encrypt_one(tfm, dst, src); |
| } |
| |
| /* |
| * Host AP crypt: host-based CCMP encryption implementation for Host AP driver |
| * |
| * Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. See README and COPYING for |
| * more details. |
| * |
| * Alternatively, this software may be distributed under the terms of BSD |
| * license. |
| */ |
| |
| static void |
| ccmp_init_blocks(struct crypto_cipher *tfm, struct ieee80211_frame *wh, |
| u_int64_t pn, size_t dlen, |
| uint8_t b0[AES_BLOCK_LEN], uint8_t aad[2 * AES_BLOCK_LEN], |
| uint8_t auth[AES_BLOCK_LEN], uint8_t s0[AES_BLOCK_LEN]) |
| { |
| #define IS_QOS_DATA(wh) IEEE80211_QOS_HAS_SEQ(wh) |
| |
| /* CCM Initial Block: |
| * Flag (Include authentication header, M=3 (8-octet MIC), |
| * L=1 (2-octet Dlen)) |
| * Nonce: 0x00 | A2 | PN |
| * Dlen */ |
| b0[0] = 0x59; |
| /* NB: b0[1] set below */ |
| IEEE80211_ADDR_COPY(b0 + 2, wh->i_addr2); |
| b0[8] = pn >> 40; |
| b0[9] = pn >> 32; |
| b0[10] = pn >> 24; |
| b0[11] = pn >> 16; |
| b0[12] = pn >> 8; |
| b0[13] = pn >> 0; |
| b0[14] = (dlen >> 8) & 0xff; |
| b0[15] = dlen & 0xff; |
| |
| /* AAD: |
| * FC with bits 4..6 and 11..13 masked to zero; 14 is always one |
| * A1 | A2 | A3 |
| * SC with bits 4..15 (seq#) masked to zero |
| * A4 (if present) |
| * QC (if present) |
| */ |
| aad[0] = 0; /* AAD length >> 8 */ |
| /* NB: aad[1] set below */ |
| aad[2] = wh->i_fc[0] & 0x8f; /* XXX magic #s */ |
| aad[3] = wh->i_fc[1] & 0xc7; /* XXX magic #s */ |
| /* NB: we know 3 addresses are contiguous */ |
| memcpy(aad + 4, wh->i_addr1, 3 * IEEE80211_ADDR_LEN); |
| aad[22] = wh->i_seq[0] & IEEE80211_SEQ_FRAG_MASK; |
| aad[23] = 0; /* all bits masked */ |
| /* |
| * Construct variable-length portion of AAD based |
| * on whether this is a 4-address frame/QOS frame. |
| * We always zero-pad to 32 bytes before running it |
| * through the cipher. |
| * |
| * We also fill in the priority bits of the CCM |
| * initial block as we know whether or not we have |
| * a QOS frame. |
| */ |
| if (IEEE80211_IS_4ADDRESS(wh)) { |
| IEEE80211_ADDR_COPY(aad + 24, |
| ((struct ieee80211_frame_addr4 *)wh)->i_addr4); |
| if (IS_QOS_DATA(wh)) { |
| struct ieee80211_qosframe_addr4 *qwh4 = |
| (struct ieee80211_qosframe_addr4 *) wh; |
| aad[30] = qwh4->i_qos[0] & 0x0f;/* just priority bits */ |
| aad[31] = 0; |
| b0[1] = aad[30]; |
| aad[1] = 22 + IEEE80211_ADDR_LEN + 2; |
| } else { |
| *(u_int16_t *)&aad[30] = 0; |
| b0[1] = 0; |
| aad[1] = 22 + IEEE80211_ADDR_LEN; |
| } |
| } else { |
| if (IS_QOS_DATA(wh)) { |
| struct ieee80211_qosframe *qwh = |
| (struct ieee80211_qosframe*) wh; |
| aad[24] = qwh->i_qos[0] & 0x0f; /* just priority bits */ |
| aad[25] = 0; |
| b0[1] = aad[24]; |
| aad[1] = 22 + 2; |
| } else { |
| *(u_int16_t *)&aad[24] = 0; |
| b0[1] = 0; |
| aad[1] = 22; |
| } |
| *(u_int16_t *)&aad[26] = 0; |
| *(u_int32_t *)&aad[28] = 0; |
| } |
| |
| /* Start with the first block and AAD */ |
| rijndael_encrypt(tfm, b0, auth); |
| xor_block(auth, aad, AES_BLOCK_LEN); |
| rijndael_encrypt(tfm, auth, auth); |
| xor_block(auth, &aad[AES_BLOCK_LEN], AES_BLOCK_LEN); |
| rijndael_encrypt(tfm, auth, auth); |
| b0[0] &= 0x07; |
| b0[14] = b0[15] = 0; |
| rijndael_encrypt(tfm, b0, s0); |
| #undef IS_QOS_DATA |
| } |
| |
| #define CCMP_ENCRYPT(_i, _b, _b0, _pos, _e, _len) do { \ |
| /* Authentication */ \ |
| xor_block(_b, _pos, _len); \ |
| rijndael_encrypt(ctx->cc_tfm, _b, _b); \ |
| /* Encryption, with counter */ \ |
| _b0[14] = (_i >> 8) & 0xff; \ |
| _b0[15] = _i & 0xff; \ |
| rijndael_encrypt(ctx->cc_tfm, _b0, _e); \ |
| xor_block(_pos, _e, _len); \ |
| } while (0) |
| |
| static int |
| ccmp_encrypt(struct ieee80211_key *key, struct sk_buff *skb0, int hdrlen) |
| { |
| struct ccmp_ctx *ctx = key->wk_private; |
| struct ieee80211_frame *wh = (struct ieee80211_frame *) skb0->data; |
| struct sk_buff *skb; |
| int data_len, i; |
| uint8_t aad[2 * AES_BLOCK_LEN], b0[AES_BLOCK_LEN], b[AES_BLOCK_LEN]; |
| uint8_t e[AES_BLOCK_LEN], s0[AES_BLOCK_LEN]; |
| uint8_t *mic, *pos; |
| u_int space; |
| |
| ctx->cc_vap->iv_stats.is_crypto_ccmp++; |
| |
| skb = skb0; |
| data_len = skb->len; |
| while (skb->next != NULL) { |
| skb = skb->next; |
| data_len += skb->len; |
| } |
| data_len -= hdrlen + ccmp.ic_header; |
| if (skb_tailroom(skb) < ccmp.ic_trailer) { |
| /* NB: should not happen */ |
| IEEE80211_NOTE_MAC(ctx->cc_vap, IEEE80211_MSG_CRYPTO, |
| wh->i_addr1, "No room for %s MIC, tailroom %u", |
| ccmp.ic_name, skb_tailroom(skb)); |
| /* XXX statistic */ |
| return 0; |
| } |
| ccmp_init_blocks(ctx->cc_tfm, wh, key->wk_keytsc, |
| data_len, b0, aad, b, s0); |
| |
| i = 1; |
| skb = skb0; |
| pos = skb->data + hdrlen + ccmp.ic_header; |
| /* NB: assumes header is entirely in first skbuf */ |
| space = skb->len - (hdrlen + ccmp.ic_header); |
| for (;;) { |
| if (space > data_len) |
| space = data_len; |
| /* |
| * Do full blocks. |
| */ |
| while (space >= AES_BLOCK_LEN) { |
| CCMP_ENCRYPT(i, b, b0, pos, e, AES_BLOCK_LEN); |
| pos += AES_BLOCK_LEN, space -= AES_BLOCK_LEN; |
| data_len -= AES_BLOCK_LEN; |
| i++; |
| } |
| if (data_len <= 0) /* no more data */ |
| break; |
| if (skb->next == NULL) { /* last buffer */ |
| if (space != 0) { |
| /* |
| * Short last block. |
| */ |
| CCMP_ENCRYPT(i, b, b0, pos, e, space); |
| } |
| break; |
| } |
| skb = skb->next; |
| if (space != 0) { |
| uint8_t *pos_next; |
| u_int space_next; |
| u_int len; |
| |
| /* |
| * Block straddles buffers, split references. We |
| * do not handle splits that require >2 buffers. |
| */ |
| pos_next = skb->data; |
| len = min(data_len, AES_BLOCK_LEN); |
| space_next = len > space ? len - space : 0; |
| KASSERT(skb->len >= space_next, |
| ("not enough data in following buffer, " |
| "skb len %u need %u\n", skb->len, space_next)); |
| |
| xor_block(b + space, pos_next, space_next); |
| CCMP_ENCRYPT(i, b, b0, pos, e, space); |
| xor_block(pos_next, e + space, space_next); |
| data_len -= len; |
| /* XXX could check for data_len <= 0 */ |
| i++; |
| |
| pos = pos_next + space_next; |
| space = skb->len - space_next; |
| } else { |
| /* |
| * Setup for next buffer. |
| */ |
| pos = skb->data; |
| space = skb->len; |
| } |
| } |
| /* tack on MIC */ |
| mic = skb_put(skb, ccmp.ic_trailer); |
| for (i = 0; i < ccmp.ic_trailer; i++) |
| mic[i] = b[i] ^ s0[i]; |
| return 1; |
| } |
| #undef CCMP_ENCRYPT |
| |
| #define CCMP_DECRYPT(_i, _b, _b0, _pos, _a, _len) do { \ |
| /* Decrypt, with counter */ \ |
| _b0[14] = (_i >> 8) & 0xff; \ |
| _b0[15] = _i & 0xff; \ |
| rijndael_encrypt(ctx->cc_tfm, _b0, _b); \ |
| xor_block(_pos, _b, _len); \ |
| /* Authentication */ \ |
| xor_block(_a, _pos, _len); \ |
| rijndael_encrypt(ctx->cc_tfm, _a, _a); \ |
| } while (0) |
| |
| static int |
| ccmp_decrypt(struct ieee80211_key *key, u_int64_t pn, struct sk_buff *skb0, int hdrlen) |
| { |
| struct ccmp_ctx *ctx = key->wk_private; |
| struct ieee80211_frame *wh = (struct ieee80211_frame *) skb0->data; |
| struct sk_buff *skb; |
| uint8_t aad[2 * AES_BLOCK_LEN]; |
| uint8_t b0[AES_BLOCK_LEN], b[AES_BLOCK_LEN], a[AES_BLOCK_LEN]; |
| size_t data_len; |
| int i; |
| uint8_t *pos, *mic; |
| u_int space; |
| |
| ctx->cc_vap->iv_stats.is_crypto_ccmp++; |
| |
| skb = skb0; |
| data_len = skb->len; |
| while (skb->next != NULL) { |
| skb = skb->next; |
| data_len += skb->len; |
| } |
| data_len -= hdrlen + ccmp.ic_header + ccmp.ic_trailer; |
| /* NB: skb left pointing at last in chain */ |
| ccmp_init_blocks(ctx->cc_tfm, wh, pn, data_len, b0, aad, a, b); |
| /* NB: this is the last in the chain */ |
| /* XXX assert skb->len >= ccmp.ic_trailer */ |
| mic = skb->data + skb->len - ccmp.ic_trailer; |
| xor_block(mic, b, ccmp.ic_trailer); |
| |
| i = 1; |
| skb = skb0; |
| pos = skb->data + hdrlen + ccmp.ic_header; |
| space = skb->len - (hdrlen + ccmp.ic_header); |
| for (;;) { |
| if (space > data_len) |
| space = data_len; |
| while (space >= AES_BLOCK_LEN) { |
| CCMP_DECRYPT(i, b, b0, pos, a, AES_BLOCK_LEN); |
| pos += AES_BLOCK_LEN; |
| space -= AES_BLOCK_LEN; |
| data_len -= AES_BLOCK_LEN; |
| i++; |
| } |
| if (data_len <= 0) /* no more data */ |
| break; |
| skb = skb->next; |
| if (skb == NULL) { /* last buffer */ |
| if (space != 0) /* short last block */ |
| CCMP_DECRYPT(i, b, b0, pos, a, space); |
| break; |
| } |
| if (space != 0) { |
| uint8_t *pos_next; |
| u_int space_next; |
| u_int len; |
| |
| /* |
| * Block straddles buffers, split references. We |
| * do not handle splits that require >2 buffers. |
| */ |
| pos_next = skb->data; |
| len = min(data_len, (size_t) AES_BLOCK_LEN); |
| space_next = len > space ? len - space : 0; |
| KASSERT(skb->len >= space_next, |
| ("not enough data in following buffer, " |
| "skb len %u need %u\n", skb->len, space_next)); |
| |
| xor_block(b+space, pos_next, space_next); |
| CCMP_DECRYPT(i, b, b0, pos, a, space); |
| xor_block(pos_next, b+space, space_next); |
| data_len -= len; |
| i++; |
| |
| pos = pos_next + space_next; |
| space = skb->len - space_next; |
| } else { |
| /* |
| * Setup for next buffer. |
| */ |
| pos = skb->data; |
| space = skb->len; |
| } |
| } |
| |
| if (memcmp(mic, a, ccmp.ic_trailer) != 0) { |
| IEEE80211_NOTE_MAC(ctx->cc_vap, IEEE80211_MSG_CRYPTO, |
| wh->i_addr2, |
| "AES-CCM decrypt failed; MIC mismatch (keyix %u, rsc %llu)", |
| key->wk_keyix, pn); |
| ctx->cc_vap->iv_stats.is_rx_ccmpmic++; |
| return 0; |
| } |
| return 1; |
| } |
| #undef CCMP_DECRYPT |
| |
| /* |
| * Module glue. |
| */ |
| |
| MODULE_AUTHOR("Errno Consulting, Sam Leffler"); |
| MODULE_DESCRIPTION("802.11 wireless support: AES-CCM cipher"); |
| #ifdef MODULE_LICENSE |
| MODULE_LICENSE("Dual BSD/GPL"); |
| #endif |
| |
| static int __init |
| init_crypto_ccmp(void) |
| { |
| ieee80211_crypto_register(&ccmp); |
| return 0; |
| } |
| module_init(init_crypto_ccmp); |
| |
| static void __exit |
| exit_crypto_ccmp(void) |
| { |
| ieee80211_crypto_unregister(&ccmp); |
| } |
| module_exit(exit_crypto_ccmp); |