| /* |
| * Temporal Key Integrity Protocol (CCMP) |
| * Copyright (c) 2010, Jouni Malinen <j@w1.fi> |
| * |
| * This software may be distributed under the terms of the BSD license. |
| * See README for more details. |
| */ |
| |
| #include "utils/includes.h" |
| |
| #include "utils/common.h" |
| #include "common/ieee802_11_defs.h" |
| #include "wlantest.h" |
| |
| |
| void wep_crypt(u8 *key, u8 *buf, size_t plen); |
| |
| |
| static inline u16 RotR1(u16 val) |
| { |
| return (val >> 1) | (val << 15); |
| } |
| |
| |
| static inline u8 Lo8(u16 val) |
| { |
| return val & 0xff; |
| } |
| |
| |
| static inline u8 Hi8(u16 val) |
| { |
| return val >> 8; |
| } |
| |
| |
| static inline u16 Lo16(u32 val) |
| { |
| return val & 0xffff; |
| } |
| |
| |
| static inline u16 Hi16(u32 val) |
| { |
| return val >> 16; |
| } |
| |
| |
| static inline u16 Mk16(u8 hi, u8 lo) |
| { |
| return lo | (((u16) hi) << 8); |
| } |
| |
| |
| static inline u16 Mk16_le(u16 *v) |
| { |
| return le_to_host16(*v); |
| } |
| |
| |
| static const u16 Sbox[256] = |
| { |
| 0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154, |
| 0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A, |
| 0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B, |
| 0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B, |
| 0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F, |
| 0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F, |
| 0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5, |
| 0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F, |
| 0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB, |
| 0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397, |
| 0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED, |
| 0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A, |
| 0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194, |
| 0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3, |
| 0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104, |
| 0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D, |
| 0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39, |
| 0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695, |
| 0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83, |
| 0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76, |
| 0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4, |
| 0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B, |
| 0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0, |
| 0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018, |
| 0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751, |
| 0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85, |
| 0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12, |
| 0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9, |
| 0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7, |
| 0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A, |
| 0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8, |
| 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A, |
| }; |
| |
| |
| static inline u16 _S_(u16 v) |
| { |
| u16 t = Sbox[Hi8(v)]; |
| return Sbox[Lo8(v)] ^ ((t << 8) | (t >> 8)); |
| } |
| |
| |
| #define PHASE1_LOOP_COUNT 8 |
| |
| static void tkip_mixing_phase1(u16 *TTAK, const u8 *TK, const u8 *TA, u32 IV32) |
| { |
| int i, j; |
| |
| /* Initialize the 80-bit TTAK from TSC (IV32) and TA[0..5] */ |
| TTAK[0] = Lo16(IV32); |
| TTAK[1] = Hi16(IV32); |
| TTAK[2] = Mk16(TA[1], TA[0]); |
| TTAK[3] = Mk16(TA[3], TA[2]); |
| TTAK[4] = Mk16(TA[5], TA[4]); |
| |
| for (i = 0; i < PHASE1_LOOP_COUNT; i++) { |
| j = 2 * (i & 1); |
| TTAK[0] += _S_(TTAK[4] ^ Mk16(TK[1 + j], TK[0 + j])); |
| TTAK[1] += _S_(TTAK[0] ^ Mk16(TK[5 + j], TK[4 + j])); |
| TTAK[2] += _S_(TTAK[1] ^ Mk16(TK[9 + j], TK[8 + j])); |
| TTAK[3] += _S_(TTAK[2] ^ Mk16(TK[13 + j], TK[12 + j])); |
| TTAK[4] += _S_(TTAK[3] ^ Mk16(TK[1 + j], TK[0 + j])) + i; |
| } |
| } |
| |
| |
| static void tkip_mixing_phase2(u8 *WEPSeed, const u8 *TK, const u16 *TTAK, |
| u16 IV16) |
| { |
| u16 PPK[6]; |
| |
| /* Step 1 - make copy of TTAK and bring in TSC */ |
| PPK[0] = TTAK[0]; |
| PPK[1] = TTAK[1]; |
| PPK[2] = TTAK[2]; |
| PPK[3] = TTAK[3]; |
| PPK[4] = TTAK[4]; |
| PPK[5] = TTAK[4] + IV16; |
| |
| /* Step 2 - 96-bit bijective mixing using S-box */ |
| PPK[0] += _S_(PPK[5] ^ Mk16_le((u16 *) &TK[0])); |
| PPK[1] += _S_(PPK[0] ^ Mk16_le((u16 *) &TK[2])); |
| PPK[2] += _S_(PPK[1] ^ Mk16_le((u16 *) &TK[4])); |
| PPK[3] += _S_(PPK[2] ^ Mk16_le((u16 *) &TK[6])); |
| PPK[4] += _S_(PPK[3] ^ Mk16_le((u16 *) &TK[8])); |
| PPK[5] += _S_(PPK[4] ^ Mk16_le((u16 *) &TK[10])); |
| |
| PPK[0] += RotR1(PPK[5] ^ Mk16_le((u16 *) &TK[12])); |
| PPK[1] += RotR1(PPK[0] ^ Mk16_le((u16 *) &TK[14])); |
| PPK[2] += RotR1(PPK[1]); |
| PPK[3] += RotR1(PPK[2]); |
| PPK[4] += RotR1(PPK[3]); |
| PPK[5] += RotR1(PPK[4]); |
| |
| /* Step 3 - bring in last of TK bits, assign 24-bit WEP IV value |
| * WEPSeed[0..2] is transmitted as WEP IV */ |
| WEPSeed[0] = Hi8(IV16); |
| WEPSeed[1] = (Hi8(IV16) | 0x20) & 0x7F; |
| WEPSeed[2] = Lo8(IV16); |
| WEPSeed[3] = Lo8((PPK[5] ^ Mk16_le((u16 *) &TK[0])) >> 1); |
| WPA_PUT_LE16(&WEPSeed[4], PPK[0]); |
| WPA_PUT_LE16(&WEPSeed[6], PPK[1]); |
| WPA_PUT_LE16(&WEPSeed[8], PPK[2]); |
| WPA_PUT_LE16(&WEPSeed[10], PPK[3]); |
| WPA_PUT_LE16(&WEPSeed[12], PPK[4]); |
| WPA_PUT_LE16(&WEPSeed[14], PPK[5]); |
| } |
| |
| |
| static inline u32 rotl(u32 val, int bits) |
| { |
| return (val << bits) | (val >> (32 - bits)); |
| } |
| |
| |
| static inline u32 rotr(u32 val, int bits) |
| { |
| return (val >> bits) | (val << (32 - bits)); |
| } |
| |
| |
| static inline u32 xswap(u32 val) |
| { |
| return ((val & 0x00ff00ff) << 8) | ((val & 0xff00ff00) >> 8); |
| } |
| |
| |
| #define michael_block(l, r) \ |
| do { \ |
| r ^= rotl(l, 17); \ |
| l += r; \ |
| r ^= xswap(l); \ |
| l += r; \ |
| r ^= rotl(l, 3); \ |
| l += r; \ |
| r ^= rotr(l, 2); \ |
| l += r; \ |
| } while (0) |
| |
| |
| static void michael_mic(const u8 *key, const u8 *hdr, const u8 *data, |
| size_t data_len, u8 *mic) |
| { |
| u32 l, r; |
| int i, blocks, last; |
| |
| l = WPA_GET_LE32(key); |
| r = WPA_GET_LE32(key + 4); |
| |
| /* Michael MIC pseudo header: DA, SA, 3 x 0, Priority */ |
| l ^= WPA_GET_LE32(hdr); |
| michael_block(l, r); |
| l ^= WPA_GET_LE32(&hdr[4]); |
| michael_block(l, r); |
| l ^= WPA_GET_LE32(&hdr[8]); |
| michael_block(l, r); |
| l ^= WPA_GET_LE32(&hdr[12]); |
| michael_block(l, r); |
| |
| /* 32-bit blocks of data */ |
| blocks = data_len / 4; |
| last = data_len % 4; |
| for (i = 0; i < blocks; i++) { |
| l ^= WPA_GET_LE32(&data[4 * i]); |
| michael_block(l, r); |
| } |
| |
| /* Last block and padding (0x5a, 4..7 x 0) */ |
| switch (last) { |
| case 0: |
| l ^= 0x5a; |
| break; |
| case 1: |
| l ^= data[4 * i] | 0x5a00; |
| break; |
| case 2: |
| l ^= data[4 * i] | (data[4 * i + 1] << 8) | 0x5a0000; |
| break; |
| case 3: |
| l ^= data[4 * i] | (data[4 * i + 1] << 8) | |
| (data[4 * i + 2] << 16) | 0x5a000000; |
| break; |
| } |
| michael_block(l, r); |
| /* l ^= 0; */ |
| michael_block(l, r); |
| |
| WPA_PUT_LE32(mic, l); |
| WPA_PUT_LE32(mic + 4, r); |
| } |
| |
| |
| static void michael_mic_hdr(const struct ieee80211_hdr *hdr11, u8 *hdr) |
| { |
| int hdrlen = 24; |
| u16 fc = le_to_host16(hdr11->frame_control); |
| |
| switch (fc & (WLAN_FC_FROMDS | WLAN_FC_TODS)) { |
| case WLAN_FC_TODS: |
| os_memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ |
| os_memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ |
| break; |
| case WLAN_FC_FROMDS: |
| os_memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ |
| os_memcpy(hdr + ETH_ALEN, hdr11->addr3, ETH_ALEN); /* SA */ |
| break; |
| case WLAN_FC_FROMDS | WLAN_FC_TODS: |
| os_memcpy(hdr, hdr11->addr3, ETH_ALEN); /* DA */ |
| os_memcpy(hdr + ETH_ALEN, hdr11 + 1, ETH_ALEN); /* SA */ |
| hdrlen += ETH_ALEN; |
| break; |
| case 0: |
| os_memcpy(hdr, hdr11->addr1, ETH_ALEN); /* DA */ |
| os_memcpy(hdr + ETH_ALEN, hdr11->addr2, ETH_ALEN); /* SA */ |
| break; |
| } |
| |
| if (WLAN_FC_GET_TYPE(fc) == WLAN_FC_TYPE_DATA && |
| (WLAN_FC_GET_STYPE(fc) & 0x08)) { |
| const u8 *qos = ((const u8 *) hdr11) + hdrlen; |
| hdr[12] = qos[0] & 0x0f; /* priority */ |
| } else |
| hdr[12] = 0; /* priority */ |
| |
| hdr[13] = hdr[14] = hdr[15] = 0; /* reserved */ |
| } |
| |
| |
| u8 * tkip_decrypt(const u8 *tk, const struct ieee80211_hdr *hdr, |
| const u8 *data, size_t data_len, size_t *decrypted_len) |
| { |
| u16 iv16; |
| u32 iv32; |
| u16 ttak[5]; |
| u8 rc4key[16]; |
| u8 *plain; |
| size_t plain_len; |
| u32 icv, rx_icv; |
| const u8 *mic_key; |
| u8 michael_hdr[16]; |
| u8 mic[8]; |
| u16 fc = le_to_host16(hdr->frame_control); |
| |
| if (data_len < 8 + 4) |
| return NULL; |
| |
| iv16 = (data[0] << 8) | data[2]; |
| iv32 = WPA_GET_LE32(&data[4]); |
| wpa_printf(MSG_EXCESSIVE, "TKIP decrypt: iv32=%08x iv16=%04x", |
| iv32, iv16); |
| |
| tkip_mixing_phase1(ttak, tk, hdr->addr2, iv32); |
| wpa_hexdump(MSG_EXCESSIVE, "TKIP TTAK", (u8 *) ttak, sizeof(ttak)); |
| tkip_mixing_phase2(rc4key, tk, ttak, iv16); |
| wpa_hexdump(MSG_EXCESSIVE, "TKIP RC4KEY", rc4key, sizeof(rc4key)); |
| |
| plain_len = data_len - 8; |
| plain = os_malloc(plain_len); |
| if (plain == NULL) |
| return NULL; |
| os_memcpy(plain, data + 8, plain_len); |
| wep_crypt(rc4key, plain, plain_len); |
| |
| icv = crc32(plain, plain_len - 4); |
| rx_icv = WPA_GET_LE32(plain + plain_len - 4); |
| if (icv != rx_icv) { |
| wpa_printf(MSG_INFO, "TKIP ICV mismatch in frame from " MACSTR, |
| MAC2STR(hdr->addr2)); |
| wpa_printf(MSG_DEBUG, "TKIP calculated ICV %08x received ICV " |
| "%08x", icv, rx_icv); |
| os_free(plain); |
| return NULL; |
| } |
| plain_len -= 4; |
| |
| /* TODO: MSDU reassembly */ |
| |
| if (plain_len < 8) { |
| wpa_printf(MSG_INFO, "TKIP: Not enough room for Michael MIC " |
| "in a frame from " MACSTR, MAC2STR(hdr->addr2)); |
| os_free(plain); |
| return NULL; |
| } |
| |
| michael_mic_hdr(hdr, michael_hdr); |
| mic_key = tk + ((fc & WLAN_FC_FROMDS) ? 16 : 24); |
| michael_mic(mic_key, michael_hdr, plain, plain_len - 8, mic); |
| if (os_memcmp(mic, plain + plain_len - 8, 8) != 0) { |
| wpa_printf(MSG_INFO, "TKIP: Michael MIC mismatch in a frame " |
| "from " MACSTR, MAC2STR(hdr->addr2)); |
| wpa_hexdump(MSG_DEBUG, "TKIP: Calculated MIC", mic, 8); |
| wpa_hexdump(MSG_DEBUG, "TKIP: Received MIC", |
| plain + plain_len - 8, 8); |
| os_free(plain); |
| return NULL; |
| } |
| |
| *decrypted_len = plain_len - 8; |
| return plain; |
| } |
| |
| |
| void tkip_get_pn(u8 *pn, const u8 *data) |
| { |
| pn[0] = data[7]; /* PN5 */ |
| pn[1] = data[6]; /* PN4 */ |
| pn[2] = data[5]; /* PN3 */ |
| pn[3] = data[4]; /* PN2 */ |
| pn[4] = data[0]; /* PN1 */ |
| pn[5] = data[2]; /* PN0 */ |
| } |
| |
| |
| u8 * tkip_encrypt(const u8 *tk, u8 *frame, size_t len, size_t hdrlen, u8 *qos, |
| u8 *pn, int keyid, size_t *encrypted_len) |
| { |
| u8 michael_hdr[16]; |
| u8 mic[8]; |
| struct ieee80211_hdr *hdr; |
| u16 fc; |
| const u8 *mic_key; |
| u8 *crypt, *pos; |
| u16 iv16; |
| u32 iv32; |
| u16 ttak[5]; |
| u8 rc4key[16]; |
| |
| if (len < sizeof(*hdr) || len < hdrlen) |
| return NULL; |
| hdr = (struct ieee80211_hdr *) frame; |
| fc = le_to_host16(hdr->frame_control); |
| |
| michael_mic_hdr(hdr, michael_hdr); |
| mic_key = tk + ((fc & WLAN_FC_FROMDS) ? 16 : 24); |
| michael_mic(mic_key, michael_hdr, frame + hdrlen, len - hdrlen, mic); |
| wpa_hexdump(MSG_EXCESSIVE, "TKIP: MIC", mic, sizeof(mic)); |
| |
| iv32 = WPA_GET_BE32(pn); |
| iv16 = WPA_GET_BE16(pn + 4); |
| tkip_mixing_phase1(ttak, tk, hdr->addr2, iv32); |
| wpa_hexdump(MSG_EXCESSIVE, "TKIP TTAK", (u8 *) ttak, sizeof(ttak)); |
| tkip_mixing_phase2(rc4key, tk, ttak, iv16); |
| wpa_hexdump(MSG_EXCESSIVE, "TKIP RC4KEY", rc4key, sizeof(rc4key)); |
| |
| crypt = os_malloc(len + 8 + sizeof(mic) + 4); |
| if (crypt == NULL) |
| return NULL; |
| os_memcpy(crypt, frame, hdrlen); |
| pos = crypt + hdrlen; |
| os_memcpy(pos, rc4key, 3); |
| pos += 3; |
| *pos++ = keyid << 6 | BIT(5); |
| *pos++ = pn[3]; |
| *pos++ = pn[2]; |
| *pos++ = pn[1]; |
| *pos++ = pn[0]; |
| |
| os_memcpy(pos, frame + hdrlen, len - hdrlen); |
| os_memcpy(pos + len - hdrlen, mic, sizeof(mic)); |
| WPA_PUT_LE32(pos + len - hdrlen + sizeof(mic), |
| crc32(pos, len - hdrlen + sizeof(mic))); |
| wep_crypt(rc4key, pos, len - hdrlen + sizeof(mic) + 4); |
| |
| *encrypted_len = len + 8 + sizeof(mic) + 4; |
| return crypt; |
| } |