/* 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)) /* * The POWER8 VSX optimized AES assembly code is borrowed from OpenSSL and * inherits OpenSSL's AES_KEY format, which stores the number of rounds after * the round keys. That assembly code is difficult to change. So for * compatibility purposes we reserve space for the extra nrounds field on PPC64. * * Note: when prepared for decryption, the round keys are just the reversed * standard round keys, not the round keys for the Equivalent Inverse Cipher. */ struct p8_aes_key { u32 rndkeys[AES_MAX_KEYLENGTH_U32]; int nrounds; }; union aes_enckey_arch { u32 rndkeys[AES_MAX_KEYLENGTH_U32]; #ifdef CONFIG_CRYPTO_LIB_AES_ARCH #if defined(CONFIG_PPC) && defined(CONFIG_SPE) /* Used unconditionally (when SPE AES code is enabled in kconfig) */ u32 spe_enc_key[AES_MAX_KEYLENGTH_U32] __aligned(8); #elif defined(CONFIG_PPC) /* * Kernels that include the POWER8 VSX optimized AES code use this field * when that code is usable at key preparation time. Otherwise they * fall back to rndkeys. In the latter case, p8.nrounds (which doesn't * overlap rndkeys) is set to 0 to differentiate the two formats. */ struct p8_aes_key p8; #elif defined(CONFIG_S390) /* Used when the CPU supports CPACF AES for this key's length */ u8 raw_key[AES_MAX_KEY_SIZE]; #elif defined(CONFIG_SPARC64) /* Used when the CPU supports the SPARC64 AES opcodes */ u64 sparc_rndkeys[AES_MAX_KEYLENGTH / sizeof(u64)]; #endif #endif /* CONFIG_CRYPTO_LIB_AES_ARCH */ }; union aes_invkey_arch { u32 inv_rndkeys[AES_MAX_KEYLENGTH_U32]; #ifdef CONFIG_CRYPTO_LIB_AES_ARCH #if defined(CONFIG_PPC) && defined(CONFIG_SPE) /* Used unconditionally (when SPE AES code is enabled in kconfig) */ u32 spe_dec_key[AES_MAX_KEYLENGTH_U32] __aligned(8); #elif defined(CONFIG_PPC) /* Used conditionally, analogous to aes_enckey_arch::p8 */ struct p8_aes_key p8; #endif #endif /* CONFIG_CRYPTO_LIB_AES_ARCH */ }; /** * struct aes_enckey - An AES key prepared for encryption * @len: Key length in bytes: 16 for AES-128, 24 for AES-192, 32 for AES-256. * @nrounds: Number of rounds: 10 for AES-128, 12 for AES-192, 14 for AES-256. * This is '6 + @len / 4' and is cached so that AES implementations * that need it don't have to recompute it for each en/decryption. * @padding: Padding to make offsetof(@k) be a multiple of 16, so that aligning * this struct to a 16-byte boundary results in @k also being 16-byte * aligned. Users aren't required to align this struct to 16 bytes, * but it may slightly improve performance. * @k: This typically contains the AES round keys as an array of '@nrounds + 1' * groups of four u32 words. However, architecture-specific implementations * of AES may store something else here, e.g. just the raw key if it's all * they need. * * Note that this struct is about half the size of struct aes_key. This is * separate from struct aes_key so that modes that need only AES encryption * (e.g. AES-GCM, AES-CTR, AES-CMAC, tweak key in AES-XTS) don't incur the time * and space overhead of computing and caching the decryption round keys. * * Note that there's no decryption-only equivalent (i.e. "struct aes_deckey"), * since (a) it's rare that modes need decryption-only, and (b) some AES * implementations use the same @k for both encryption and decryption, either * always or conditionally; in the latter case both @k and @inv_k are needed. */ struct aes_enckey { u32 len; u32 nrounds; u32 padding[2]; union aes_enckey_arch k; }; /** * struct aes_key - An AES key prepared for encryption and decryption * @aes_enckey: Common fields and the key prepared for encryption * @inv_k: This generally contains the round keys for the AES Equivalent * Inverse Cipher, as an array of '@nrounds + 1' groups of four u32 * words. However, architecture-specific implementations of AES may * store something else here. For example, they may leave this field * uninitialized if they use @k for both encryption and decryption. */ struct aes_key { struct aes_enckey; /* Include all fields of aes_enckey. */ union aes_invkey_arch inv_k; }; /* * 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; }; /* * validate key length for AES algorithms */ static inline int aes_check_keylen(size_t keylen) { switch (keylen) { case AES_KEYSIZE_128: case AES_KEYSIZE_192: case AES_KEYSIZE_256: break; default: return -EINVAL; } return 0; } /** * 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); /* * The following functions are temporarily exported for use by the AES mode * implementations in arch/$(SRCARCH)/crypto/. These exports will go away when * that code is migrated into lib/crypto/. */ #ifdef CONFIG_ARM64 int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key, unsigned int key_len); #elif defined(CONFIG_PPC) void ppc_expand_key_128(u32 *key_enc, const u8 *key); void ppc_expand_key_192(u32 *key_enc, const u8 *key); void ppc_expand_key_256(u32 *key_enc, const u8 *key); void ppc_generate_decrypt_key(u32 *key_dec, u32 *key_enc, unsigned int key_len); void ppc_encrypt_ecb(u8 *out, const u8 *in, u32 *key_enc, u32 rounds, u32 bytes); void ppc_decrypt_ecb(u8 *out, const u8 *in, u32 *key_dec, u32 rounds, u32 bytes); void ppc_encrypt_cbc(u8 *out, const u8 *in, u32 *key_enc, u32 rounds, u32 bytes, u8 *iv); void ppc_decrypt_cbc(u8 *out, const u8 *in, u32 *key_dec, u32 rounds, u32 bytes, u8 *iv); void ppc_crypt_ctr(u8 *out, const u8 *in, u32 *key_enc, u32 rounds, u32 bytes, u8 *iv); void ppc_encrypt_xts(u8 *out, const u8 *in, u32 *key_enc, u32 rounds, u32 bytes, u8 *iv, u32 *key_twk); void ppc_decrypt_xts(u8 *out, const u8 *in, u32 *key_dec, u32 rounds, u32 bytes, u8 *iv, u32 *key_twk); int aes_p8_set_encrypt_key(const u8 *userKey, const int bits, struct p8_aes_key *key); int aes_p8_set_decrypt_key(const u8 *userKey, const int bits, struct p8_aes_key *key); void aes_p8_encrypt(const u8 *in, u8 *out, const struct p8_aes_key *key); void aes_p8_decrypt(const u8 *in, u8 *out, const struct p8_aes_key *key); void aes_p8_cbc_encrypt(const u8 *in, u8 *out, size_t len, const struct p8_aes_key *key, u8 *iv, const int enc); void aes_p8_ctr32_encrypt_blocks(const u8 *in, u8 *out, size_t len, const struct p8_aes_key *key, const u8 *iv); void aes_p8_xts_encrypt(const u8 *in, u8 *out, size_t len, const struct p8_aes_key *key1, const struct p8_aes_key *key2, u8 *iv); void aes_p8_xts_decrypt(const u8 *in, u8 *out, size_t len, const struct p8_aes_key *key1, const struct p8_aes_key *key2, u8 *iv); #elif defined(CONFIG_SPARC64) void aes_sparc64_key_expand(const u32 *in_key, u64 *output_key, unsigned int key_len); void aes_sparc64_load_encrypt_keys_128(const u64 *key); void aes_sparc64_load_encrypt_keys_192(const u64 *key); void aes_sparc64_load_encrypt_keys_256(const u64 *key); void aes_sparc64_load_decrypt_keys_128(const u64 *key); void aes_sparc64_load_decrypt_keys_192(const u64 *key); void aes_sparc64_load_decrypt_keys_256(const u64 *key); void aes_sparc64_ecb_encrypt_128(const u64 *key, const u64 *input, u64 *output, unsigned int len); void aes_sparc64_ecb_encrypt_192(const u64 *key, const u64 *input, u64 *output, unsigned int len); void aes_sparc64_ecb_encrypt_256(const u64 *key, const u64 *input, u64 *output, unsigned int len); void aes_sparc64_ecb_decrypt_128(const u64 *key, const u64 *input, u64 *output, unsigned int len); void aes_sparc64_ecb_decrypt_192(const u64 *key, const u64 *input, u64 *output, unsigned int len); void aes_sparc64_ecb_decrypt_256(const u64 *key, const u64 *input, u64 *output, unsigned int len); void aes_sparc64_cbc_encrypt_128(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_cbc_encrypt_192(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_cbc_encrypt_256(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_cbc_decrypt_128(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_cbc_decrypt_192(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_cbc_decrypt_256(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_ctr_crypt_128(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_ctr_crypt_192(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); void aes_sparc64_ctr_crypt_256(const u64 *key, const u64 *input, u64 *output, unsigned int len, u64 *iv); #endif /** * aes_preparekey() - Prepare an AES key for encryption and decryption * @key: (output) The key structure to initialize * @in_key: The raw AES key * @key_len: Length of the raw key in bytes. Should be either AES_KEYSIZE_128, * AES_KEYSIZE_192, or AES_KEYSIZE_256. * * This prepares an AES key for both the encryption and decryption directions of * the block cipher. Typically this involves expanding the raw key into both * the standard round keys and the Equivalent Inverse Cipher round keys, but * some architecture-specific implementations don't do the full expansion here. * * The caller is responsible for zeroizing both the struct aes_key and the raw * key once they are no longer needed. * * If you don't need decryption support, use aes_prepareenckey() instead. * * Return: 0 on success or -EINVAL if the given key length is invalid. No other * errors are possible, so callers that always pass a valid key length * don't need to check for errors. * * Context: Any context. */ int aes_preparekey(struct aes_key *key, const u8 *in_key, size_t key_len); /** * aes_prepareenckey() - Prepare an AES key for encryption-only * @key: (output) The key structure to initialize * @in_key: The raw AES key * @key_len: Length of the raw key in bytes. Should be either AES_KEYSIZE_128, * AES_KEYSIZE_192, or AES_KEYSIZE_256. * * This prepares an AES key for only the encryption direction of the block * cipher. Typically this involves expanding the raw key into only the standard * round keys, resulting in a struct about half the size of struct aes_key. * * The caller is responsible for zeroizing both the struct aes_enckey and the * raw key once they are no longer needed. * * Note that while the resulting prepared key supports only AES encryption, it * can still be used for decrypting in a mode of operation that uses AES in only * the encryption (forward) direction, for example counter mode. * * Return: 0 on success or -EINVAL if the given key length is invalid. No other * errors are possible, so callers that always pass a valid key length * don't need to check for errors. * * Context: Any context. */ int aes_prepareenckey(struct aes_enckey *key, const u8 *in_key, size_t key_len); typedef union { const struct aes_enckey *enc_key; const struct aes_key *full_key; } aes_encrypt_arg __attribute__ ((__transparent_union__)); /** * aes_encrypt() - Encrypt a single AES block * @key: The AES key, as a pointer to either an encryption-only key * (struct aes_enckey) or a full, bidirectional key (struct aes_key). * @out: Buffer to store the ciphertext block * @in: Buffer containing the plaintext block * * Context: Any context. */ void aes_encrypt(aes_encrypt_arg key, u8 out[at_least AES_BLOCK_SIZE], const u8 in[at_least AES_BLOCK_SIZE]); /** * aes_decrypt() - Decrypt a single AES block * @key: The AES key, previously initialized by aes_preparekey() * @out: Buffer to store the plaintext block * @in: Buffer containing the ciphertext block * * Context: Any context. */ void aes_decrypt(const struct aes_key *key, u8 out[at_least AES_BLOCK_SIZE], const u8 in[at_least AES_BLOCK_SIZE]); extern const u8 crypto_aes_sbox[]; extern const u8 crypto_aes_inv_sbox[]; extern const u32 aes_enc_tab[256]; extern const u32 aes_dec_tab[256]; void aescfb_encrypt(const struct aes_enckey *key, u8 *dst, const u8 *src, int len, const u8 iv[AES_BLOCK_SIZE]); void aescfb_decrypt(const struct aes_enckey *key, u8 *dst, const u8 *src, int len, const u8 iv[AES_BLOCK_SIZE]); #endif
