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-rw-r--r--net/mac80211/aes_cmac.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/net/mac80211/aes_cmac.c b/net/mac80211/aes_cmac.c
new file mode 100644
index 0000000..2fb6558
--- /dev/null
+++ b/net/mac80211/aes_cmac.c
@@ -0,0 +1,71 @@
+/*
+ * AES-128-CMAC with TLen 16 for IEEE 802.11w BIP
+ * Copyright 2008, Jouni Malinen <j@w1.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/export.h>
+#include <linux/err.h>
+#include <crypto/aes.h>
+
+#include <net/mac80211.h>
+#include "key.h"
+#include "aes_cmac.h"
+
+#define CMAC_TLEN 8 /* CMAC TLen = 64 bits (8 octets) */
+#define CMAC_TLEN_256 16 /* CMAC TLen = 128 bits (16 octets) */
+#define AAD_LEN 20
+
+static const u8 zero[CMAC_TLEN_256];
+
+void ieee80211_aes_cmac(struct crypto_shash *tfm, const u8 *aad,
+ const u8 *data, size_t data_len, u8 *mic)
+{
+ SHASH_DESC_ON_STACK(desc, tfm);
+ u8 out[AES_BLOCK_SIZE];
+
+ desc->tfm = tfm;
+
+ crypto_shash_init(desc);
+ crypto_shash_update(desc, aad, AAD_LEN);
+ crypto_shash_update(desc, data, data_len - CMAC_TLEN);
+ crypto_shash_finup(desc, zero, CMAC_TLEN, out);
+
+ memcpy(mic, out, CMAC_TLEN);
+}
+
+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);
+
+ desc->tfm = tfm;
+
+ crypto_shash_init(desc);
+ crypto_shash_update(desc, aad, AAD_LEN);
+ crypto_shash_update(desc, data, data_len - CMAC_TLEN_256);
+ crypto_shash_finup(desc, zero, CMAC_TLEN_256, mic);
+}
+
+struct crypto_shash *ieee80211_aes_cmac_key_setup(const u8 key[],
+ size_t key_len)
+{
+ struct crypto_shash *tfm;
+
+ tfm = crypto_alloc_shash("cmac(aes)", 0, 0);
+ if (!IS_ERR(tfm))
+ crypto_shash_setkey(tfm, key, key_len);
+
+ return tfm;
+}
+
+void ieee80211_aes_cmac_key_free(struct crypto_shash *tfm)
+{
+ crypto_free_shash(tfm);
+}