xref: /openbmc/linux/include/crypto/internal/cipher.h (revision 63705da3)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
4  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
5  * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
6  *
7  * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
8  * and Nettle, by Niels Möller.
9  */
10 
11 #ifndef _CRYPTO_INTERNAL_CIPHER_H
12 #define _CRYPTO_INTERNAL_CIPHER_H
13 
14 #include <crypto/algapi.h>
15 
16 struct crypto_cipher {
17 	struct crypto_tfm base;
18 };
19 
20 /**
21  * DOC: Single Block Cipher API
22  *
23  * The single block cipher API is used with the ciphers of type
24  * CRYPTO_ALG_TYPE_CIPHER (listed as type "cipher" in /proc/crypto).
25  *
26  * Using the single block cipher API calls, operations with the basic cipher
27  * primitive can be implemented. These cipher primitives exclude any block
28  * chaining operations including IV handling.
29  *
30  * The purpose of this single block cipher API is to support the implementation
31  * of templates or other concepts that only need to perform the cipher operation
32  * on one block at a time. Templates invoke the underlying cipher primitive
33  * block-wise and process either the input or the output data of these cipher
34  * operations.
35  */
36 
37 static inline struct crypto_cipher *__crypto_cipher_cast(struct crypto_tfm *tfm)
38 {
39 	return (struct crypto_cipher *)tfm;
40 }
41 
42 /**
43  * crypto_alloc_cipher() - allocate single block cipher handle
44  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
45  *	     single block cipher
46  * @type: specifies the type of the cipher
47  * @mask: specifies the mask for the cipher
48  *
49  * Allocate a cipher handle for a single block cipher. The returned struct
50  * crypto_cipher is the cipher handle that is required for any subsequent API
51  * invocation for that single block cipher.
52  *
53  * Return: allocated cipher handle in case of success; IS_ERR() is true in case
54  *	   of an error, PTR_ERR() returns the error code.
55  */
56 static inline struct crypto_cipher *crypto_alloc_cipher(const char *alg_name,
57 							u32 type, u32 mask)
58 {
59 	type &= ~CRYPTO_ALG_TYPE_MASK;
60 	type |= CRYPTO_ALG_TYPE_CIPHER;
61 	mask |= CRYPTO_ALG_TYPE_MASK;
62 
63 	return __crypto_cipher_cast(crypto_alloc_base(alg_name, type, mask));
64 }
65 
66 static inline struct crypto_tfm *crypto_cipher_tfm(struct crypto_cipher *tfm)
67 {
68 	return &tfm->base;
69 }
70 
71 /**
72  * crypto_free_cipher() - zeroize and free the single block cipher handle
73  * @tfm: cipher handle to be freed
74  */
75 static inline void crypto_free_cipher(struct crypto_cipher *tfm)
76 {
77 	crypto_free_tfm(crypto_cipher_tfm(tfm));
78 }
79 
80 /**
81  * crypto_has_cipher() - Search for the availability of a single block cipher
82  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
83  *	     single block cipher
84  * @type: specifies the type of the cipher
85  * @mask: specifies the mask for the cipher
86  *
87  * Return: true when the single block cipher is known to the kernel crypto API;
88  *	   false otherwise
89  */
90 static inline int crypto_has_cipher(const char *alg_name, u32 type, u32 mask)
91 {
92 	type &= ~CRYPTO_ALG_TYPE_MASK;
93 	type |= CRYPTO_ALG_TYPE_CIPHER;
94 	mask |= CRYPTO_ALG_TYPE_MASK;
95 
96 	return crypto_has_alg(alg_name, type, mask);
97 }
98 
99 /**
100  * crypto_cipher_blocksize() - obtain block size for cipher
101  * @tfm: cipher handle
102  *
103  * The block size for the single block cipher referenced with the cipher handle
104  * tfm is returned. The caller may use that information to allocate appropriate
105  * memory for the data returned by the encryption or decryption operation
106  *
107  * Return: block size of cipher
108  */
109 static inline unsigned int crypto_cipher_blocksize(struct crypto_cipher *tfm)
110 {
111 	return crypto_tfm_alg_blocksize(crypto_cipher_tfm(tfm));
112 }
113 
114 static inline unsigned int crypto_cipher_alignmask(struct crypto_cipher *tfm)
115 {
116 	return crypto_tfm_alg_alignmask(crypto_cipher_tfm(tfm));
117 }
118 
119 static inline u32 crypto_cipher_get_flags(struct crypto_cipher *tfm)
120 {
121 	return crypto_tfm_get_flags(crypto_cipher_tfm(tfm));
122 }
123 
124 static inline void crypto_cipher_set_flags(struct crypto_cipher *tfm,
125 					   u32 flags)
126 {
127 	crypto_tfm_set_flags(crypto_cipher_tfm(tfm), flags);
128 }
129 
130 static inline void crypto_cipher_clear_flags(struct crypto_cipher *tfm,
131 					     u32 flags)
132 {
133 	crypto_tfm_clear_flags(crypto_cipher_tfm(tfm), flags);
134 }
135 
136 /**
137  * crypto_cipher_setkey() - set key for cipher
138  * @tfm: cipher handle
139  * @key: buffer holding the key
140  * @keylen: length of the key in bytes
141  *
142  * The caller provided key is set for the single block cipher referenced by the
143  * cipher handle.
144  *
145  * Note, the key length determines the cipher type. Many block ciphers implement
146  * different cipher modes depending on the key size, such as AES-128 vs AES-192
147  * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
148  * is performed.
149  *
150  * Return: 0 if the setting of the key was successful; < 0 if an error occurred
151  */
152 int crypto_cipher_setkey(struct crypto_cipher *tfm,
153 			 const u8 *key, unsigned int keylen);
154 
155 /**
156  * crypto_cipher_encrypt_one() - encrypt one block of plaintext
157  * @tfm: cipher handle
158  * @dst: points to the buffer that will be filled with the ciphertext
159  * @src: buffer holding the plaintext to be encrypted
160  *
161  * Invoke the encryption operation of one block. The caller must ensure that
162  * the plaintext and ciphertext buffers are at least one block in size.
163  */
164 void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
165 			       u8 *dst, const u8 *src);
166 
167 /**
168  * crypto_cipher_decrypt_one() - decrypt one block of ciphertext
169  * @tfm: cipher handle
170  * @dst: points to the buffer that will be filled with the plaintext
171  * @src: buffer holding the ciphertext to be decrypted
172  *
173  * Invoke the decryption operation of one block. The caller must ensure that
174  * the plaintext and ciphertext buffers are at least one block in size.
175  */
176 void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
177 			       u8 *dst, const u8 *src);
178 
179 struct crypto_cipher_spawn {
180 	struct crypto_spawn base;
181 };
182 
183 static inline int crypto_grab_cipher(struct crypto_cipher_spawn *spawn,
184 				     struct crypto_instance *inst,
185 				     const char *name, u32 type, u32 mask)
186 {
187 	type &= ~CRYPTO_ALG_TYPE_MASK;
188 	type |= CRYPTO_ALG_TYPE_CIPHER;
189 	mask |= CRYPTO_ALG_TYPE_MASK;
190 	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
191 }
192 
193 static inline void crypto_drop_cipher(struct crypto_cipher_spawn *spawn)
194 {
195 	crypto_drop_spawn(&spawn->base);
196 }
197 
198 static inline struct crypto_alg *crypto_spawn_cipher_alg(
199        struct crypto_cipher_spawn *spawn)
200 {
201 	return spawn->base.alg;
202 }
203 
204 static inline struct crypto_cipher *crypto_spawn_cipher(
205 	struct crypto_cipher_spawn *spawn)
206 {
207 	u32 type = CRYPTO_ALG_TYPE_CIPHER;
208 	u32 mask = CRYPTO_ALG_TYPE_MASK;
209 
210 	return __crypto_cipher_cast(crypto_spawn_tfm(&spawn->base, type, mask));
211 }
212 
213 static inline struct cipher_alg *crypto_cipher_alg(struct crypto_cipher *tfm)
214 {
215 	return &crypto_cipher_tfm(tfm)->__crt_alg->cra_cipher;
216 }
217 
218 #endif
219