/* * ;;_crypt_wep.cpp * iwi2200 * * Created by Asaf Algawi on 8/21/07. * Copyright 2007 __MyCompanyName__. All rights reserved. * */ #include "iwi2200.h" #include "net/ieee80211.h" int m_append(mbuf_t m0, int len, u8* cp) { mbuf_t m,n; int remainder, space; for (m = m0; mbuf_next(m) != NULL; m=mbuf_next(m)); remainder = len; space = mbuf_trailingspace(m); if (space > 0 ) { if (space > remainder) space = remainder; bcopy(cp, ((u8*) mbuf_data(m)) + mbuf_len(m), space); mbuf_setlen(m,mbuf_len(m)+space); cp+= space, remainder -=space; } while (remainder > 0) { mbuf_get(MBUF_WAITOK, mbuf_type(m),&n); if (!n) break; mbuf_setlen(n,min(mbuf_len(m),remainder)); bcopy(cp, ((u8*) mbuf_data(m)), mbuf_len(n)); cp += mbuf_len(n), remainder -= mbuf_len(n); mbuf_setnext(m,n); m=n; } if (mbuf_flags(m0) & MBUF_PKTHDR) mbuf_pkthdr_setlen(m,len-remainder); return remainder == 0; }; static const uint32_t crc32_table[256] = { 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L, 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L, 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L, 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL, 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L, 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L, 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L, 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL, 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L, 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL, 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L, 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L, 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L, 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL, 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL, 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L, 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL, 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L, 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L, 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L, 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL, 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L, 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L, 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL, 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L, 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L, 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L, 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L, 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L, 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL, 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL, 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L, 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L, 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL, 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL, 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L, 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL, 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L, 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL, 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L, 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL, 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L, 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L, 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL, 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L, 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L, 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L, 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L, 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L, 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L, 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL, 0x2d02ef8dL}; struct prism2_wep_data { u32 iv; #define WEP_KEY_LEN 13 u8 key[WEP_KEY_LEN + 1]; u8 key_len; u8 key_idx; //struct crypto_blkcipher *tx_tfm; //struct crypto_blkcipher *rx_tfm; }; static int prism2_wep_encrypt(mbuf_t skb, int hdr_len, void *priv) { if (!priv) return -1; #define S_SWAP(a,b) do { uint8_t t = S[a]; S[a] = S[b]; S[b] = t; } while(0) struct prism2_wep_data *wep = (prism2_wep_data*) priv; mbuf_t m = skb; u8 rc4key[19]; u8 icv[4]; u32 i,j,k,crc; size_t buflen,data_len; u8 S[256]; u8 *pos; u_int off, keylen; //mbuf_pullup(&m,hdr_len); u8 *data = (u8*) mbuf_data(m); /*copy public key*/ bcopy(data+hdr_len, rc4key, 3); /*copy private key*/ bcopy(wep->key, rc4key+3,wep->key_len); IWI_DEBUG("key created\n"); /*setup RC4 state*/ for (i=0; i<256; i++) { S[i] = i; } j=0; keylen = wep->key_len+3; for (i=0; i<256; i++) { j = (j+S[i] + rc4key[i % keylen]) & 0xff; S_SWAP(i,j); } /*compute CRC32 over unencrypted data*/ off=hdr_len + 4; data_len = mbuf_len(m) - off; crc = ~0; i=j=0; pos = (u8*) mbuf_data(m) + off; buflen = mbuf_len(m)-off; for (;;) { if (buflen > data_len) buflen =data_len; data_len -= buflen; for (k=0; k> 8); i = (i+1) & 0xff; j = (j+S[i]) & 0xff; S_SWAP(i,j); *pos++ ^= S[(S[i] + S[j]) & 0xff]; } if (mbuf_next(m)==NULL) { if (data_len!=0) { IWI_ERR("out of data for WEP encryption"); return 0; } break; } m = mbuf_next(m); pos = (u8*) mbuf_data(m); buflen = mbuf_len(m); } 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<4; k++) { i= (i+1) & 0xff; j= (j+S[i]) & 0xff; S_SWAP(i,j); icv[k] ^= S[(S[i] + S[j]) & 0xff]; } //IWI_DEBUG("calling m_append\n"); bcopy(icv, skb_put(m,4),4); return 1; //return m_append(m, 4, icv); #undef S_SWAP } static int prism2_wep_decrypt(mbuf_t skb, int hdr_len, void* priv) { if (!priv) return -1; #define S_SWAP(a,b) do { uint8_t t = S[a]; S[a] = S[b]; S[b] = t; } while(0) struct prism2_wep_data *wep = (prism2_wep_data*) priv; mbuf_t m = skb; uint8_t rc4key[19]; uint8_t icv[4]; uint32_t i,j,k,crc; size_t buflen, data_len; uint8_t S[256]; uint8_t *pos; u_int off,keylen; rc4key[0]=0; //mbuf_pullup(&m,hdr_len); /*copy public part of key.*/ bcopy((uint8_t*) mbuf_data(m) + hdr_len, rc4key, 3); /*copy private part of key.*/ bcopy(wep->key, rc4key+3,wep->key_len); IWI_DEBUG("public + private key: %s\n",rc4key); // setup rc4 state: for (i=0; i<256; i++) S[i] = i; j=0; keylen = wep->key_len + 3; for (i=0; i<256; i++) { j = (j+S[i] +rc4key[i % keylen]) & 0xff; S_SWAP(i,j); } off = hdr_len + 4; data_len = mbuf_len(m) - (off + 4); //compute crc32 over unencrypted data and apply rc4 to data crc = ~0; i = j = 0; pos = ((uint8_t*) mbuf_data(m)) + off; buflen = mbuf_len(m) - off; for (;;) { if (buflen > data_len) buflen = data_len; data_len -= buflen; for (k=0; k>8); pos++; } m = mbuf_next(m); if (m==NULL) { if (data_len != 0) { IWI_ERR("missing_data"); return 0; } break; } pos = (uint8_t*) mbuf_data(m); buflen = mbuf_len(m); } crc = ~crc; //encrypt little endian crc32 and verify it match with recieved ICV icv[0] = crc; icv[1] = crc>>8; icv[2] = crc>>16; icv[3] = crc>>24; for (k=0; k< 4; k++) { i = (i+1) & 0xff; j = (j+S[i]) & 0xff; S_SWAP(i,j); uint8_t pos_t=*pos++; if ((icv[k] ^ S[(S[i] + S[j]) & 0xff]) != pos_t) //ICV mismatch, drop frame. { IWI_ERR("key mismatch\n"); return -2; } } return 1; #undef S_SWAP } static int prism2_wep_set_key(void *key, int len, u8 * seq, void *priv) { if (!priv) return -1; struct prism2_wep_data *wep = (prism2_wep_data *)priv; if (len < 0 || len > WEP_KEY_LEN) return -1; bcopy(key, wep->key, len); wep->key_len = len; return 0; } static int wep_decrypt(mbuf_t skb, int hdr_len, void* priv) { mbuf_t m = skb; if (prism2_wep_decrypt(m,hdr_len,priv)!=1) return 0; //#define ovbcopy(f, t, l) bcopy((f), (t), (l)) bcopy(mbuf_data(m),((uint8_t*) mbuf_data(m)) + 4,hdr_len); mbuf_adj(skb,4); mbuf_adj(skb,-4); //mbuf_setflags(skb,mbuf_flags(m) | MBUF_PKTHDR); return 1; } static int wep_encrypt(mbuf_t skb, int hdr_len, void* priv) { uint32_t iv; uint8_t *ivp; int hdrlen; hdrlen = hdr_len; struct prism2_wep_data *wep = (prism2_wep_data *)priv; mbuf_prepend(&skb,4,MBUF_WAITOK); if (!skb) return 0; ivp = (uint8_t*)mbuf_data(skb); bcopy(ivp + 4, ivp, hdrlen); ivp += hdrlen; iv = wep->iv; if ((iv & 0xff00) == 0xff00) { int b = (iv & 0xff0000) >> 16; if (3<=b && b<16) { iv +=0x100; } } wep->iv = iv + 1; #if defined(__BIG_ENDIAN__) // apple ppc hardware ivp[0] = iv >> 0; ivp[1] = iv >> 8; ivp[2] = iv >> 16; #else // intel hardware ivp[2] = iv >> 0; ivp[1] = iv >> 8; ivp[0] = iv >> 16; #endif ivp[3] = wep->key_idx; /* call software encrypt our hardware support hardware encryption but since i'm not so familiar with the driver code and i have this beutiful implementation of the BSD WEP encryption in the BSD IEEE80211 layer i will use that. maybe other devs can set the hardware encryption. */ IWI_DEBUG("calling encrypt\n"); return prism2_wep_encrypt(skb,hdr_len,wep); //return 1; } static int prism2_wep_get_key(void *key, int len, u8 * seq, void *priv) { if (!priv) return -1; struct prism2_wep_data *wep = (prism2_wep_data *)priv; if (len < wep->key_len) return -1; bcopy( wep->key, key, wep->key_len); return wep->key_len; } static char *prism2_wep_print_stats(char *p, void *priv) { if (!priv) return NULL; struct prism2_wep_data *wep = (prism2_wep_data *)priv; p += sprintf(p, "key[%d] alg=WEP len=%d\n", wep->key_idx, wep->key_len); return p; } static void *prism2_wep_init(int keyidx) { struct prism2_wep_data *priv; priv = (prism2_wep_data*) IOMalloc(sizeof(*priv)); if (priv == NULL) goto fail; priv->key_idx = keyidx; /* #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,18) priv->tx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(priv->tx_tfm)) { #else priv->tx_tfm = crypto_alloc_tfm("arc4", 0); if (priv->tx_tfm == NULL) { #endif printk(KERN_DEBUG "ieee80211_crypt_wep: could not allocate " "crypto API arc4\n"); priv->tx_tfm = NULL; goto fail; } #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,18) priv->rx_tfm = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(priv->rx_tfm)) { #else priv->rx_tfm = crypto_alloc_tfm("arc4", 0); if (priv->rx_tfm == NULL) { #endif printk(KERN_DEBUG "ieee80211_crypt_wep: could not allocate " "crypto API arc4\n"); priv->rx_tfm = NULL; goto fail; } */ /* start WEP IV from a random value */ read_random(&priv->iv, 4); return priv; fail: if (priv) { //if (priv->tx_tfm); // crypto_free_blkcipher(priv->tx_tfm); //if (priv->rx_tfm); // crypto_free_blkcipher(priv->rx_tfm); IOFree(priv,sizeof(*priv)); } return NULL; } static void prism2_wep_deinit(void *priv) { if (!priv) return; struct prism2_wep_data *_priv = (prism2_wep_data*)priv; if (_priv) { //if (_priv->tx_tfm); // crypto_free_blkcipher(_priv->tx_tfm); //if (_priv->rx_tfm); // crypto_free_blkcipher(_priv->rx_tfm); } IOFree(_priv, sizeof(*_priv)); } /* Add WEP IV/key info to a frame that has at least 4 bytes of headroom */ static int prism2_wep_build_iv(mbuf_t skb, int hdr_len, u8 *key, int keylen, void *priv) { if (!priv) { IWI_ERR("null priv"); return -1; } struct prism2_wep_data *wep = (prism2_wep_data*) priv; u32 klen, len; u8 *pos; if (mbuf_leadingspace(skb) < 4 || mbuf_len(skb) < hdr_len) return -1; len = mbuf_len(skb) - hdr_len; pos = (u8*)skb_push(skb, 4); memmove(pos, pos + 4, hdr_len); pos += hdr_len; klen = 3 + wep->key_len; wep->iv++; /* Fluhrer, Mantin, and Shamir have reported weaknesses in the key * scheduling algorithm of RC4. At least IVs (KeyByte + 3, 0xff, N) * can be used to speedup attacks, so avoid using them. */ if ((wep->iv & 0xff00) == 0xff00) { u8 B = (wep->iv >> 16) & 0xff; if (B >= 3 && B < klen) wep->iv += 0x0100; } /* Prepend 24-bit IV to RC4 key and TX frame */ *pos++ = (wep->iv >> 16) & 0xff; *pos++ = (wep->iv >> 8) & 0xff; *pos++ = wep->iv & 0xff; *pos++ = wep->key_idx << 6; return 0; } static struct list_head list; static struct ieee80211_crypto_ops ieee80211_crypt_wep = { "WEP", list, prism2_wep_init, prism2_wep_deinit, prism2_wep_build_iv, wep_encrypt, wep_decrypt, NULL, NULL, prism2_wep_set_key, prism2_wep_get_key, prism2_wep_print_stats, NULL, NULL, 4, 4}; void darwin_iwi2200::free_wep(ieee80211_crypt_data *tmp) { if (tmp) { tmp->ops=NULL; IOFree(tmp->priv,sizeof(prism2_wep_data)); tmp->priv=NULL; IOFree(tmp,sizeof(ieee80211_crypt_data)); tmp=NULL; } } ieee80211_crypt_data* darwin_iwi2200::init_wep(void *key, int len, int idx) { ieee80211_crypt_data* tmp = (ieee80211_crypt_data*) IOMalloc(sizeof(ieee80211_crypt_data)+sizeof(struct prism2_wep_data)); tmp->ops=&ieee80211_crypt_wep; tmp->priv=tmp->ops->init(idx); prism2_wep_set_key(key, len, NULL, tmp->priv); /*int i=0; IWI_LOG("key password ["); while( i< ((prism2_wep_data*)(tmp->priv))->key_len) { IOLog("%x",((prism2_wep_data*)(tmp->priv))->key[i++]); if (i<((prism2_wep_data*)(tmp->priv))->key_len) IOLog(":"); } IOLog("] "); i=0; while( i< ((prism2_wep_data*)(tmp->priv))->key_len) { IOLog("%c",((prism2_wep_data*)(tmp->priv))->key[i++]); } IOLog(" size %d\n",((prism2_wep_data*)(tmp->priv))->key_len);*/ return tmp; }