From 2d5d4b0a6da1271a7dfa9a7052870361e72ba424 Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Sat, 22 Feb 2020 15:25:45 +0200 Subject: mac80211: Update BIP to support Beacon frames When BIP is used to protect Beacon frames, the Timestamp field is masked to zero. Otherwise, the BIP processing is identical to the way it was already used with group-addressed Robust Management frames. Signed-off-by: Jouni Malinen Link: https://lore.kernel.org/r/20200222132548.20835-4-jouni@codeaurora.org Signed-off-by: Johannes Berg --- net/mac80211/aes_cmac.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) (limited to 'net/mac80211/aes_cmac.c') diff --git a/net/mac80211/aes_cmac.c b/net/mac80211/aes_cmac.c index 57748cab0e28..b31f1021ad9c 100644 --- a/net/mac80211/aes_cmac.c +++ b/net/mac80211/aes_cmac.c @@ -26,12 +26,20 @@ void ieee80211_aes_cmac(struct crypto_shash *tfm, const u8 *aad, { SHASH_DESC_ON_STACK(desc, tfm); u8 out[AES_BLOCK_SIZE]; + const __le16 *fc; desc->tfm = tfm; crypto_shash_init(desc); crypto_shash_update(desc, aad, AAD_LEN); - crypto_shash_update(desc, data, data_len - CMAC_TLEN); + fc = (const __le16 *)aad; + if (ieee80211_is_beacon(*fc)) { + /* mask Timestamp field to zero */ + crypto_shash_update(desc, zero, 8); + crypto_shash_update(desc, data + 8, data_len - 8 - CMAC_TLEN); + } else { + crypto_shash_update(desc, data, data_len - CMAC_TLEN); + } crypto_shash_finup(desc, zero, CMAC_TLEN, out); memcpy(mic, out, CMAC_TLEN); @@ -41,12 +49,21 @@ void ieee80211_aes_cmac_256(struct crypto_shash *tfm, const u8 *aad, const u8 *data, size_t data_len, u8 *mic) { SHASH_DESC_ON_STACK(desc, tfm); + const __le16 *fc; desc->tfm = tfm; crypto_shash_init(desc); crypto_shash_update(desc, aad, AAD_LEN); - crypto_shash_update(desc, data, data_len - CMAC_TLEN_256); + fc = (const __le16 *)aad; + if (ieee80211_is_beacon(*fc)) { + /* mask Timestamp field to zero */ + crypto_shash_update(desc, zero, 8); + crypto_shash_update(desc, data + 8, + data_len - 8 - CMAC_TLEN_256); + } else { + crypto_shash_update(desc, data, data_len - CMAC_TLEN_256); + } crypto_shash_finup(desc, zero, CMAC_TLEN_256, mic); } -- cgit