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-rw-r--r--include/crypto/aes.h90
1 files changed, 90 insertions, 0 deletions
diff --git a/include/crypto/aes.h b/include/crypto/aes.h
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+++ b/include/crypto/aes.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Common values for AES algorithms
+ */
+
+#ifndef _CRYPTO_AES_H
+#define _CRYPTO_AES_H
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+
+#define AES_MIN_KEY_SIZE 16
+#define AES_MAX_KEY_SIZE 32
+#define AES_KEYSIZE_128 16
+#define AES_KEYSIZE_192 24
+#define AES_KEYSIZE_256 32
+#define AES_BLOCK_SIZE 16
+#define AES_MAX_KEYLENGTH (15 * 16)
+#define AES_MAX_KEYLENGTH_U32 (AES_MAX_KEYLENGTH / sizeof(u32))
+
+/*
+ * Please ensure that the first two fields are 16-byte aligned
+ * relative to the start of the structure, i.e., don't move them!
+ */
+struct crypto_aes_ctx {
+ u32 key_enc[AES_MAX_KEYLENGTH_U32];
+ u32 key_dec[AES_MAX_KEYLENGTH_U32];
+ u32 key_length;
+};
+
+extern const u32 crypto_ft_tab[4][256] ____cacheline_aligned;
+extern const u32 crypto_it_tab[4][256] ____cacheline_aligned;
+
+/*
+ * validate key length for AES algorithms
+ */
+static inline int aes_check_keylen(unsigned int keylen)
+{
+ switch (keylen) {
+ case AES_KEYSIZE_128:
+ case AES_KEYSIZE_192:
+ case AES_KEYSIZE_256:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+ unsigned int key_len);
+
+/**
+ * aes_expandkey - Expands the AES key as described in FIPS-197
+ * @ctx: The location where the computed key will be stored.
+ * @in_key: The supplied key.
+ * @key_len: The length of the supplied key.
+ *
+ * Returns 0 on success. The function fails only if an invalid key size (or
+ * pointer) is supplied.
+ * The expanded key size is 240 bytes (max of 14 rounds with a unique 16 bytes
+ * key schedule plus a 16 bytes key which is used before the first round).
+ * The decryption key is prepared for the "Equivalent Inverse Cipher" as
+ * described in FIPS-197. The first slot (16 bytes) of each key (enc or dec) is
+ * for the initial combination, the second slot for the first round and so on.
+ */
+int aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
+ unsigned int key_len);
+
+/**
+ * aes_encrypt - Encrypt a single AES block
+ * @ctx: Context struct containing the key schedule
+ * @out: Buffer to store the ciphertext
+ * @in: Buffer containing the plaintext
+ */
+void aes_encrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);
+
+/**
+ * aes_decrypt - Decrypt a single AES block
+ * @ctx: Context struct containing the key schedule
+ * @out: Buffer to store the plaintext
+ * @in: Buffer containing the ciphertext
+ */
+void aes_decrypt(const struct crypto_aes_ctx *ctx, u8 *out, const u8 *in);
+
+extern const u8 crypto_aes_sbox[];
+extern const u8 crypto_aes_inv_sbox[];
+
+#endif