1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Shared glue code for 128bit block ciphers
4 */
5
6 #ifndef _CRYPTO_GLUE_HELPER_H
7 #define _CRYPTO_GLUE_HELPER_H
8
9 #include <crypto/internal/skcipher.h>
10 #include <linux/kernel.h>
11 #include <asm/fpu/api.h>
12 #include <crypto/b128ops.h>
13
14 typedef void (*common_glue_func_t)(void *ctx, u8 *dst, const u8 *src);
15 typedef void (*common_glue_cbc_func_t)(void *ctx, u128 *dst, const u128 *src);
16 typedef void (*common_glue_ctr_func_t)(void *ctx, u128 *dst, const u128 *src,
17 le128 *iv);
18 typedef void (*common_glue_xts_func_t)(void *ctx, u128 *dst, const u128 *src,
19 le128 *iv);
20
21 #define GLUE_FUNC_CAST(fn) ((common_glue_func_t)(fn))
22 #define GLUE_CBC_FUNC_CAST(fn) ((common_glue_cbc_func_t)(fn))
23 #define GLUE_CTR_FUNC_CAST(fn) ((common_glue_ctr_func_t)(fn))
24 #define GLUE_XTS_FUNC_CAST(fn) ((common_glue_xts_func_t)(fn))
25
26 struct common_glue_func_entry {
27 unsigned int num_blocks; /* number of blocks that @fn will process */
28 union {
29 common_glue_func_t ecb;
30 common_glue_cbc_func_t cbc;
31 common_glue_ctr_func_t ctr;
32 common_glue_xts_func_t xts;
33 } fn_u;
34 };
35
36 struct common_glue_ctx {
37 unsigned int num_funcs;
38 int fpu_blocks_limit; /* -1 means fpu not needed at all */
39
40 /*
41 * First funcs entry must have largest num_blocks and last funcs entry
42 * must have num_blocks == 1!
43 */
44 struct common_glue_func_entry funcs[];
45 };
46
glue_fpu_begin(unsigned int bsize,int fpu_blocks_limit,struct blkcipher_desc * desc,bool fpu_enabled,unsigned int nbytes)47 static inline bool glue_fpu_begin(unsigned int bsize, int fpu_blocks_limit,
48 struct blkcipher_desc *desc,
49 bool fpu_enabled, unsigned int nbytes)
50 {
51 if (likely(fpu_blocks_limit < 0))
52 return false;
53
54 if (fpu_enabled)
55 return true;
56
57 /*
58 * Vector-registers are only used when chunk to be processed is large
59 * enough, so do not enable FPU until it is necessary.
60 */
61 if (nbytes < bsize * (unsigned int)fpu_blocks_limit)
62 return false;
63
64 if (desc) {
65 /* prevent sleeping if FPU is in use */
66 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
67 }
68
69 kernel_fpu_begin();
70 return true;
71 }
72
glue_skwalk_fpu_begin(unsigned int bsize,int fpu_blocks_limit,struct skcipher_walk * walk,bool fpu_enabled,unsigned int nbytes)73 static inline bool glue_skwalk_fpu_begin(unsigned int bsize,
74 int fpu_blocks_limit,
75 struct skcipher_walk *walk,
76 bool fpu_enabled, unsigned int nbytes)
77 {
78 if (likely(fpu_blocks_limit < 0))
79 return false;
80
81 if (fpu_enabled)
82 return true;
83
84 /*
85 * Vector-registers are only used when chunk to be processed is large
86 * enough, so do not enable FPU until it is necessary.
87 */
88 if (nbytes < bsize * (unsigned int)fpu_blocks_limit)
89 return false;
90
91 /* prevent sleeping if FPU is in use */
92 skcipher_walk_atomise(walk);
93
94 kernel_fpu_begin();
95 return true;
96 }
97
glue_fpu_end(bool fpu_enabled)98 static inline void glue_fpu_end(bool fpu_enabled)
99 {
100 if (fpu_enabled)
101 kernel_fpu_end();
102 }
103
le128_to_be128(be128 * dst,const le128 * src)104 static inline void le128_to_be128(be128 *dst, const le128 *src)
105 {
106 dst->a = cpu_to_be64(le64_to_cpu(src->a));
107 dst->b = cpu_to_be64(le64_to_cpu(src->b));
108 }
109
be128_to_le128(le128 * dst,const be128 * src)110 static inline void be128_to_le128(le128 *dst, const be128 *src)
111 {
112 dst->a = cpu_to_le64(be64_to_cpu(src->a));
113 dst->b = cpu_to_le64(be64_to_cpu(src->b));
114 }
115
le128_inc(le128 * i)116 static inline void le128_inc(le128 *i)
117 {
118 u64 a = le64_to_cpu(i->a);
119 u64 b = le64_to_cpu(i->b);
120
121 b++;
122 if (!b)
123 a++;
124
125 i->a = cpu_to_le64(a);
126 i->b = cpu_to_le64(b);
127 }
128
129 extern int glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx,
130 struct blkcipher_desc *desc,
131 struct scatterlist *dst,
132 struct scatterlist *src, unsigned int nbytes);
133
134 extern int glue_cbc_encrypt_128bit(const common_glue_func_t fn,
135 struct blkcipher_desc *desc,
136 struct scatterlist *dst,
137 struct scatterlist *src,
138 unsigned int nbytes);
139
140 extern int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx,
141 struct blkcipher_desc *desc,
142 struct scatterlist *dst,
143 struct scatterlist *src,
144 unsigned int nbytes);
145
146 extern int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx,
147 struct blkcipher_desc *desc,
148 struct scatterlist *dst,
149 struct scatterlist *src, unsigned int nbytes);
150
151 extern int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
152 struct blkcipher_desc *desc,
153 struct scatterlist *dst,
154 struct scatterlist *src, unsigned int nbytes,
155 common_glue_func_t tweak_fn, void *tweak_ctx,
156 void *crypt_ctx);
157
158 extern int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx,
159 struct blkcipher_desc *desc,
160 struct scatterlist *dst,
161 struct scatterlist *src, unsigned int nbytes,
162 common_glue_func_t tweak_fn, void *tweak_ctx,
163 void *crypt_ctx);
164
165 extern int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
166 struct skcipher_request *req,
167 common_glue_func_t tweak_fn, void *tweak_ctx,
168 void *crypt_ctx);
169
170 extern void glue_xts_crypt_128bit_one(void *ctx, u128 *dst, const u128 *src,
171 le128 *iv, common_glue_func_t fn);
172
173 #endif /* _CRYPTO_GLUE_HELPER_H */
174