projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 765cb46a JM |
2 | /* |
| 3 | * AES-128-CMAC with TLen 16 for IEEE 802.11w BIP | |
| 4 | * Copyright 2008, Jouni Malinen <j@w1.fi> | |
| 765cb46a JM |
5 | */ |
| 6 | ||
| 7 | #include <linux/kernel.h> | |
| 8 | #include <linux/types.h> | |
| 9 | #include <linux/crypto.h> | |
| 4afebd63 | 10 | #include <linux/export.h> |
| 765cb46a | 11 | #include <linux/err.h> |
| 0cd20a27 | 12 | #include <crypto/aes.h> |
| 765cb46a JM |
13 | |
| 14 | #include <net/mac80211.h> | |
| 15 | #include "key.h" | |
| 16 | #include "aes_cmac.h" | |
| 17 | ||
| 765cb46a | 18 | #define CMAC_TLEN 8 /* CMAC TLen = 64 bits (8 octets) */ |
| 56c52da2 | 19 | #define CMAC_TLEN_256 16 /* CMAC TLen = 128 bits (16 octets) */ |
| 765cb46a JM |
20 | #define AAD_LEN 20 |
| 21 | ||
| 26717828 | 22 | static const u8 zero[CMAC_TLEN_256]; |
| 765cb46a | 23 | |
| 26717828 | 24 | void ieee80211_aes_cmac(struct crypto_shash *tfm, const u8 *aad, |
| 765cb46a JM |
25 | const u8 *data, size_t data_len, u8 *mic) |
| 26 | { | |
| 26717828 AB |
27 | SHASH_DESC_ON_STACK(desc, tfm); |
| 28 | u8 out[AES_BLOCK_SIZE]; | |
| 2d5d4b0a | 29 | const __le16 *fc; |
| 765cb46a | 30 | |
| 26717828 | 31 | desc->tfm = tfm; |
| 765cb46a | 32 | |
| 26717828 AB |
33 | crypto_shash_init(desc); |
| 34 | crypto_shash_update(desc, aad, AAD_LEN); | |
| 2d5d4b0a JM |
35 | fc = (const __le16 *)aad; |
| 36 | if (ieee80211_is_beacon(*fc)) { | |
| 37 | /* mask Timestamp field to zero */ | |
| 38 | crypto_shash_update(desc, zero, 8); | |
| 39 | crypto_shash_update(desc, data + 8, data_len - 8 - CMAC_TLEN); | |
| 40 | } else { | |
| 41 | crypto_shash_update(desc, data, data_len - CMAC_TLEN); | |
| 42 | } | |
| 26717828 AB |
43 | crypto_shash_finup(desc, zero, CMAC_TLEN, out); |
| 44 | ||
| 45 | memcpy(mic, out, CMAC_TLEN); | |
| 765cb46a JM |
46 | } |
| 47 | ||
| 26717828 | 48 | void ieee80211_aes_cmac_256(struct crypto_shash *tfm, const u8 *aad, |
| 56c52da2 JM |
49 | const u8 *data, size_t data_len, u8 *mic) |
| 50 | { | |
| 26717828 | 51 | SHASH_DESC_ON_STACK(desc, tfm); |
| 2d5d4b0a | 52 | const __le16 *fc; |
| 56c52da2 | 53 | |
| 26717828 | 54 | desc->tfm = tfm; |
| 56c52da2 | 55 | |
| 26717828 AB |
56 | crypto_shash_init(desc); |
| 57 | crypto_shash_update(desc, aad, AAD_LEN); | |
| 2d5d4b0a JM |
58 | fc = (const __le16 *)aad; |
| 59 | if (ieee80211_is_beacon(*fc)) { | |
| 60 | /* mask Timestamp field to zero */ | |
| 61 | crypto_shash_update(desc, zero, 8); | |
| 62 | crypto_shash_update(desc, data + 8, | |
| 63 | data_len - 8 - CMAC_TLEN_256); | |
| 64 | } else { | |
| 65 | crypto_shash_update(desc, data, data_len - CMAC_TLEN_256); | |
| 66 | } | |
| 26717828 | 67 | crypto_shash_finup(desc, zero, CMAC_TLEN_256, mic); |
| 56c52da2 | 68 | } |
| 765cb46a | 69 | |
| 26717828 AB |
70 | struct crypto_shash *ieee80211_aes_cmac_key_setup(const u8 key[], |
| 71 | size_t key_len) | |
| 765cb46a | 72 | { |
| 26717828 | 73 | struct crypto_shash *tfm; |
| 765cb46a | 74 | |
| 26717828 | 75 | tfm = crypto_alloc_shash("cmac(aes)", 0, 0); |
| 1ac62ba7 | 76 | if (!IS_ERR(tfm)) |
| 26717828 | 77 | crypto_shash_setkey(tfm, key, key_len); |
| 765cb46a JM |
78 | |
| 79 | return tfm; | |
| 80 | } | |
| 81 | ||
| 26717828 | 82 | void ieee80211_aes_cmac_key_free(struct crypto_shash *tfm) |
| 765cb46a | 83 | { |
| 26717828 | 84 | crypto_free_shash(tfm); |
| 765cb46a | 85 | } |