1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Cryptographic API. 4 * 5 * Single-block cipher operations. 6 * 7 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> 8 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au> 9 */ 10 11 #include <crypto/algapi.h> 12 #include <linux/kernel.h> 13 #include <linux/crypto.h> 14 #include <linux/errno.h> 15 #include <linux/slab.h> 16 #include <linux/string.h> 17 #include "internal.h" 18 19 static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key, 20 unsigned int keylen) 21 { 22 struct cipher_alg *cia = crypto_cipher_alg(tfm); 23 unsigned long alignmask = crypto_cipher_alignmask(tfm); 24 int ret; 25 u8 *buffer, *alignbuffer; 26 unsigned long absize; 27 28 absize = keylen + alignmask; 29 buffer = kmalloc(absize, GFP_ATOMIC); 30 if (!buffer) 31 return -ENOMEM; 32 33 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 34 memcpy(alignbuffer, key, keylen); 35 ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen); 36 memset(alignbuffer, 0, keylen); 37 kfree(buffer); 38 return ret; 39 40 } 41 42 int crypto_cipher_setkey(struct crypto_cipher *tfm, 43 const u8 *key, unsigned int keylen) 44 { 45 struct cipher_alg *cia = crypto_cipher_alg(tfm); 46 unsigned long alignmask = crypto_cipher_alignmask(tfm); 47 48 if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) 49 return -EINVAL; 50 51 if ((unsigned long)key & alignmask) 52 return setkey_unaligned(tfm, key, keylen); 53 54 return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen); 55 } 56 EXPORT_SYMBOL_GPL(crypto_cipher_setkey); 57 58 static inline void cipher_crypt_one(struct crypto_cipher *tfm, 59 u8 *dst, const u8 *src, bool enc) 60 { 61 unsigned long alignmask = crypto_cipher_alignmask(tfm); 62 struct cipher_alg *cia = crypto_cipher_alg(tfm); 63 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = 64 enc ? cia->cia_encrypt : cia->cia_decrypt; 65 66 if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) { 67 unsigned int bs = crypto_cipher_blocksize(tfm); 68 u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK]; 69 u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 70 71 memcpy(tmp, src, bs); 72 fn(crypto_cipher_tfm(tfm), tmp, tmp); 73 memcpy(dst, tmp, bs); 74 } else { 75 fn(crypto_cipher_tfm(tfm), dst, src); 76 } 77 } 78 79 void crypto_cipher_encrypt_one(struct crypto_cipher *tfm, 80 u8 *dst, const u8 *src) 81 { 82 cipher_crypt_one(tfm, dst, src, true); 83 } 84 EXPORT_SYMBOL_GPL(crypto_cipher_encrypt_one); 85 86 void crypto_cipher_decrypt_one(struct crypto_cipher *tfm, 87 u8 *dst, const u8 *src) 88 { 89 cipher_crypt_one(tfm, dst, src, false); 90 } 91 EXPORT_SYMBOL_GPL(crypto_cipher_decrypt_one); 92