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 <crypto/internal/cipher.h> 13 #include <linux/kernel.h> 14 #include <linux/crypto.h> 15 #include <linux/errno.h> 16 #include <linux/slab.h> 17 #include <linux/string.h> 18 #include "internal.h" 19 20 static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key, 21 unsigned int keylen) 22 { 23 struct cipher_alg *cia = crypto_cipher_alg(tfm); 24 unsigned long alignmask = crypto_cipher_alignmask(tfm); 25 int ret; 26 u8 *buffer, *alignbuffer; 27 unsigned long absize; 28 29 absize = keylen + alignmask; 30 buffer = kmalloc(absize, GFP_ATOMIC); 31 if (!buffer) 32 return -ENOMEM; 33 34 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 35 memcpy(alignbuffer, key, keylen); 36 ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen); 37 memset(alignbuffer, 0, keylen); 38 kfree(buffer); 39 return ret; 40 41 } 42 43 int crypto_cipher_setkey(struct crypto_cipher *tfm, 44 const u8 *key, unsigned int keylen) 45 { 46 struct cipher_alg *cia = crypto_cipher_alg(tfm); 47 unsigned long alignmask = crypto_cipher_alignmask(tfm); 48 49 if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize) 50 return -EINVAL; 51 52 if ((unsigned long)key & alignmask) 53 return setkey_unaligned(tfm, key, keylen); 54 55 return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen); 56 } 57 EXPORT_SYMBOL_NS_GPL(crypto_cipher_setkey, CRYPTO_INTERNAL); 58 59 static inline void cipher_crypt_one(struct crypto_cipher *tfm, 60 u8 *dst, const u8 *src, bool enc) 61 { 62 unsigned long alignmask = crypto_cipher_alignmask(tfm); 63 struct cipher_alg *cia = crypto_cipher_alg(tfm); 64 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = 65 enc ? cia->cia_encrypt : cia->cia_decrypt; 66 67 if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) { 68 unsigned int bs = crypto_cipher_blocksize(tfm); 69 u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK]; 70 u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 71 72 memcpy(tmp, src, bs); 73 fn(crypto_cipher_tfm(tfm), tmp, tmp); 74 memcpy(dst, tmp, bs); 75 } else { 76 fn(crypto_cipher_tfm(tfm), dst, src); 77 } 78 } 79 80 void crypto_cipher_encrypt_one(struct crypto_cipher *tfm, 81 u8 *dst, const u8 *src) 82 { 83 cipher_crypt_one(tfm, dst, src, true); 84 } 85 EXPORT_SYMBOL_NS_GPL(crypto_cipher_encrypt_one, CRYPTO_INTERNAL); 86 87 void crypto_cipher_decrypt_one(struct crypto_cipher *tfm, 88 u8 *dst, const u8 *src) 89 { 90 cipher_crypt_one(tfm, dst, src, false); 91 } 92 EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, CRYPTO_INTERNAL); 93 94 struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher) 95 { 96 struct crypto_tfm *tfm = crypto_cipher_tfm(cipher); 97 struct crypto_alg *alg = tfm->__crt_alg; 98 struct crypto_cipher *ncipher; 99 struct crypto_tfm *ntfm; 100 101 if (alg->cra_init) 102 return ERR_PTR(-ENOSYS); 103 104 if (unlikely(!crypto_mod_get(alg))) 105 return ERR_PTR(-ESTALE); 106 107 ntfm = __crypto_alloc_tfmgfp(alg, CRYPTO_ALG_TYPE_CIPHER, 108 CRYPTO_ALG_TYPE_MASK, GFP_ATOMIC); 109 if (IS_ERR(ntfm)) { 110 crypto_mod_put(alg); 111 return ERR_CAST(ntfm); 112 } 113 114 ntfm->crt_flags = tfm->crt_flags; 115 116 ncipher = __crypto_cipher_cast(ntfm); 117 118 return ncipher; 119 } 120 EXPORT_SYMBOL_GPL(crypto_clone_cipher); 121