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Diffstat (limited to 'include/crypto/aes.h')
| -rw-r--r-- | include/crypto/aes.h | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/include/crypto/aes.h b/include/crypto/aes.h new file mode 100644 index 000000000..3279cfa54 --- /dev/null +++ b/include/crypto/aes.h @@ -0,0 +1,401 @@ +/* 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); +asmlinkage void neon_aes_ecb_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks); +asmlinkage void neon_aes_ecb_decrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks); +asmlinkage void neon_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks, u8 iv[]); +asmlinkage void neon_aes_cbc_decrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks, u8 iv[]); +asmlinkage void neon_aes_cbc_cts_encrypt(u8 out[], u8 const in[], + u32 const rk[], int rounds, int bytes, + u8 const iv[]); +asmlinkage void neon_aes_cbc_cts_decrypt(u8 out[], u8 const in[], + u32 const rk[], int rounds, int bytes, + u8 const iv[]); +asmlinkage void neon_aes_ctr_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int bytes, u8 ctr[]); +asmlinkage void neon_aes_xctr_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int bytes, u8 ctr[], + int byte_ctr); +asmlinkage void neon_aes_xts_encrypt(u8 out[], u8 const in[], u32 const rk1[], + int rounds, int bytes, u32 const rk2[], + u8 iv[], int first); +asmlinkage void neon_aes_xts_decrypt(u8 out[], u8 const in[], u32 const rk1[], + int rounds, int bytes, u32 const rk2[], + u8 iv[], int first); +asmlinkage void neon_aes_essiv_cbc_encrypt(u8 out[], u8 const in[], + u32 const rk1[], int rounds, + int blocks, u8 iv[], + u32 const rk2[]); +asmlinkage void neon_aes_essiv_cbc_decrypt(u8 out[], u8 const in[], + u32 const rk1[], int rounds, + int blocks, u8 iv[], + u32 const rk2[]); + +asmlinkage void ce_aes_ecb_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks); +asmlinkage void ce_aes_ecb_decrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks); +asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks, u8 iv[]); +asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int blocks, u8 iv[]); +asmlinkage void ce_aes_cbc_cts_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int bytes, u8 const iv[]); +asmlinkage void ce_aes_cbc_cts_decrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int bytes, u8 const iv[]); +asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int bytes, u8 ctr[]); +asmlinkage void ce_aes_xctr_encrypt(u8 out[], u8 const in[], u32 const rk[], + int rounds, int bytes, u8 ctr[], + int byte_ctr); +asmlinkage void ce_aes_xts_encrypt(u8 out[], u8 const in[], u32 const rk1[], + int rounds, int bytes, u32 const rk2[], + u8 iv[], int first); +asmlinkage void ce_aes_xts_decrypt(u8 out[], u8 const in[], u32 const rk1[], + int rounds, int bytes, u32 const rk2[], + u8 iv[], int first); +asmlinkage void ce_aes_essiv_cbc_encrypt(u8 out[], u8 const in[], + u32 const rk1[], int rounds, + int blocks, u8 iv[], u32 const rk2[]); +asmlinkage void ce_aes_essiv_cbc_decrypt(u8 out[], u8 const in[], + u32 const rk1[], int rounds, + int blocks, u8 iv[], u32 const rk2[]); +asmlinkage void ce_aes_mac_update(u8 const in[], u32 const rk[], int rounds, + size_t blocks, u8 dg[], int enc_before, + int enc_after); +#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, bool 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 |