b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | /* |
| 2 | * BIP |
| 3 | * Copyright (c) 2010-2012, Jouni Malinen <j@w1.fi> |
| 4 | * |
| 5 | * This software may be distributed under the terms of the BSD license. |
| 6 | * See README for more details. |
| 7 | */ |
| 8 | |
| 9 | #include "utils/includes.h" |
| 10 | |
| 11 | #include "utils/common.h" |
| 12 | #include "common/ieee802_11_defs.h" |
| 13 | #include "crypto/aes_wrap.h" |
| 14 | #include "wlantest.h" |
| 15 | |
| 16 | |
| 17 | u8 * bip_protect(const u8 *igtk, size_t igtk_len, u8 *frame, size_t len, |
| 18 | u8 *ipn, int keyid, size_t *prot_len) |
| 19 | { |
| 20 | u8 *prot, *pos, *buf; |
| 21 | u8 mic[16]; |
| 22 | u16 fc; |
| 23 | struct ieee80211_hdr *hdr; |
| 24 | size_t plen; |
| 25 | |
| 26 | plen = len + (igtk_len == 32 ? 26 : 18); |
| 27 | prot = os_malloc(plen); |
| 28 | if (prot == NULL) |
| 29 | return NULL; |
| 30 | os_memcpy(prot, frame, len); |
| 31 | pos = prot + len; |
| 32 | *pos++ = WLAN_EID_MMIE; |
| 33 | *pos++ = igtk_len == 32 ? 24 : 16; |
| 34 | WPA_PUT_LE16(pos, keyid); |
| 35 | pos += 2; |
| 36 | os_memcpy(pos, ipn, 6); |
| 37 | pos += 6; |
| 38 | os_memset(pos, 0, igtk_len == 32 ? 16 : 8); /* MIC */ |
| 39 | |
| 40 | buf = os_malloc(plen + 20 - 24); |
| 41 | if (buf == NULL) { |
| 42 | os_free(prot); |
| 43 | return NULL; |
| 44 | } |
| 45 | |
| 46 | /* BIP AAD: FC(masked) A1 A2 A3 */ |
| 47 | hdr = (struct ieee80211_hdr *) frame; |
| 48 | fc = le_to_host16(hdr->frame_control); |
| 49 | fc &= ~(WLAN_FC_RETRY | WLAN_FC_PWRMGT | WLAN_FC_MOREDATA); |
| 50 | WPA_PUT_LE16(buf, fc); |
| 51 | os_memcpy(buf + 2, hdr->addr1, 3 * ETH_ALEN); |
| 52 | os_memcpy(buf + 20, prot + 24, plen - 24); |
| 53 | wpa_hexdump(MSG_MSGDUMP, "BIP: AAD|Body(masked)", buf, plen + 20 - 24); |
| 54 | /* MIC = L(AES-128-CMAC(AAD || Frame Body(masked)), 0, 64) */ |
| 55 | if (omac1_aes_128(igtk, buf, plen + 20 - 24, mic) < 0) { |
| 56 | os_free(prot); |
| 57 | os_free(buf); |
| 58 | return NULL; |
| 59 | } |
| 60 | os_free(buf); |
| 61 | |
| 62 | os_memcpy(pos, mic, igtk_len == 32 ? 16 : 8); |
| 63 | wpa_hexdump(MSG_DEBUG, "BIP MMIE MIC", pos, igtk_len == 32 ? 16 : 8); |
| 64 | |
| 65 | *prot_len = plen; |
| 66 | return prot; |
| 67 | } |
| 68 | |
| 69 | |
| 70 | u8 * bip_gmac_protect(const u8 *igtk, size_t igtk_len, u8 *frame, size_t len, |
| 71 | u8 *ipn, int keyid, size_t *prot_len) |
| 72 | { |
| 73 | u8 *prot, *pos, *buf; |
| 74 | u16 fc; |
| 75 | struct ieee80211_hdr *hdr; |
| 76 | size_t plen; |
| 77 | u8 nonce[12], *npos; |
| 78 | |
| 79 | plen = len + 26; |
| 80 | prot = os_malloc(plen); |
| 81 | if (prot == NULL) |
| 82 | return NULL; |
| 83 | os_memcpy(prot, frame, len); |
| 84 | pos = prot + len; |
| 85 | *pos++ = WLAN_EID_MMIE; |
| 86 | *pos++ = 24; |
| 87 | WPA_PUT_LE16(pos, keyid); |
| 88 | pos += 2; |
| 89 | os_memcpy(pos, ipn, 6); |
| 90 | pos += 6; |
| 91 | os_memset(pos, 0, 16); /* MIC */ |
| 92 | |
| 93 | buf = os_malloc(plen + 20 - 24); |
| 94 | if (buf == NULL) { |
| 95 | os_free(prot); |
| 96 | return NULL; |
| 97 | } |
| 98 | |
| 99 | /* BIP AAD: FC(masked) A1 A2 A3 */ |
| 100 | hdr = (struct ieee80211_hdr *) frame; |
| 101 | fc = le_to_host16(hdr->frame_control); |
| 102 | fc &= ~(WLAN_FC_RETRY | WLAN_FC_PWRMGT | WLAN_FC_MOREDATA); |
| 103 | WPA_PUT_LE16(buf, fc); |
| 104 | os_memcpy(buf + 2, hdr->addr1, 3 * ETH_ALEN); |
| 105 | os_memcpy(buf + 20, prot + 24, plen - 24); |
| 106 | wpa_hexdump(MSG_MSGDUMP, "BIP-GMAC: AAD|Body(masked)", |
| 107 | buf, plen + 20 - 24); |
| 108 | |
| 109 | /* Nonce: A2 | IPN */ |
| 110 | os_memcpy(nonce, hdr->addr2, ETH_ALEN); |
| 111 | npos = nonce + ETH_ALEN; |
| 112 | *npos++ = ipn[5]; |
| 113 | *npos++ = ipn[4]; |
| 114 | *npos++ = ipn[3]; |
| 115 | *npos++ = ipn[2]; |
| 116 | *npos++ = ipn[1]; |
| 117 | *npos++ = ipn[0]; |
| 118 | wpa_hexdump(MSG_EXCESSIVE, "BIP-GMAC: Nonce", nonce, sizeof(nonce)); |
| 119 | |
| 120 | /* MIC = AES-GMAC(AAD || Frame Body(masked)) */ |
| 121 | if (aes_gmac(igtk, igtk_len, nonce, sizeof(nonce), |
| 122 | buf, plen + 20 - 24, pos) < 0) { |
| 123 | os_free(prot); |
| 124 | os_free(buf); |
| 125 | return NULL; |
| 126 | } |
| 127 | os_free(buf); |
| 128 | |
| 129 | wpa_hexdump(MSG_DEBUG, "BIP-GMAC MMIE MIC", pos, 16); |
| 130 | |
| 131 | *prot_len = plen; |
| 132 | return prot; |
| 133 | } |