xref: /src/crypto/openssl/include/crypto/md32_common.h (revision f25b8c9fb4f58cf61adb47d7570abe7caa6d385d)
1 /*
2  * Copyright 1999-2022 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 /*-
11  * This is a generic 32 bit "collector" for message digest algorithms.
12  * Whenever needed it collects input character stream into chunks of
13  * 32 bit values and invokes a block function that performs actual hash
14  * calculations.
15  *
16  * Porting guide.
17  *
18  * Obligatory macros:
19  *
20  * DATA_ORDER_IS_BIG_ENDIAN or DATA_ORDER_IS_LITTLE_ENDIAN
21  *      this macro defines byte order of input stream.
22  * HASH_CBLOCK
23  *      size of a unit chunk HASH_BLOCK operates on.
24  * HASH_LONG
25  *      has to be at least 32 bit wide.
26  * HASH_CTX
27  *      context structure that at least contains following
28  *      members:
29  *              typedef struct {
30  *                      ...
31  *                      HASH_LONG       Nl,Nh;
32  *                      either {
33  *                      HASH_LONG       data[HASH_LBLOCK];
34  *                      unsigned char   data[HASH_CBLOCK];
35  *                      };
36  *                      unsigned int    num;
37  *                      ...
38  *                      } HASH_CTX;
39  *      data[] vector is expected to be zeroed upon first call to
40  *      HASH_UPDATE.
41  * HASH_UPDATE
42  *      name of "Update" function, implemented here.
43  * HASH_TRANSFORM
44  *      name of "Transform" function, implemented here.
45  * HASH_FINAL
46  *      name of "Final" function, implemented here.
47  * HASH_BLOCK_DATA_ORDER
48  *      name of "block" function capable of treating *unaligned* input
49  *      message in original (data) byte order, implemented externally.
50  * HASH_MAKE_STRING
51  *      macro converting context variables to an ASCII hash string.
52  *
53  * MD5 example:
54  *
55  *      #define DATA_ORDER_IS_LITTLE_ENDIAN
56  *
57  *      #define HASH_LONG               MD5_LONG
58  *      #define HASH_CTX                MD5_CTX
59  *      #define HASH_CBLOCK             MD5_CBLOCK
60  *      #define HASH_UPDATE             MD5_Update
61  *      #define HASH_TRANSFORM          MD5_Transform
62  *      #define HASH_FINAL              MD5_Final
63  *      #define HASH_BLOCK_DATA_ORDER   md5_block_data_order
64  */
65 
66 #ifndef OSSL_CRYPTO_MD32_COMMON_H
67 #define OSSL_CRYPTO_MD32_COMMON_H
68 #pragma once
69 
70 #include <openssl/crypto.h>
71 
72 #if !defined(DATA_ORDER_IS_BIG_ENDIAN) && !defined(DATA_ORDER_IS_LITTLE_ENDIAN)
73 #error "DATA_ORDER must be defined!"
74 #endif
75 
76 #ifndef HASH_CBLOCK
77 #error "HASH_CBLOCK must be defined!"
78 #endif
79 #ifndef HASH_LONG
80 #error "HASH_LONG must be defined!"
81 #endif
82 #ifndef HASH_CTX
83 #error "HASH_CTX must be defined!"
84 #endif
85 
86 #ifndef HASH_UPDATE
87 #error "HASH_UPDATE must be defined!"
88 #endif
89 #ifndef HASH_TRANSFORM
90 #error "HASH_TRANSFORM must be defined!"
91 #endif
92 #ifndef HASH_FINAL
93 #error "HASH_FINAL must be defined!"
94 #endif
95 
96 #ifndef HASH_BLOCK_DATA_ORDER
97 #error "HASH_BLOCK_DATA_ORDER must be defined!"
98 #endif
99 
100 #define ROTATE(a, n) (((a) << (n)) | (((a) & 0xffffffff) >> (32 - (n))))
101 
102 #ifndef PEDANTIC
103 #if defined(__GNUC__) && __GNUC__ >= 2 && !defined(OPENSSL_NO_ASM) && !defined(OPENSSL_NO_INLINE_ASM)
104 #if defined(__riscv_zbb) || defined(__riscv_zbkb)
105 #if __riscv_xlen == 64
106 #undef ROTATE
107 #define ROTATE(x, n) ({ MD32_REG_T ret;            \
108                        asm ("roriw %0, %1, %2"        \
109                        : "=r"(ret)                    \
110                        : "r"(x), "i"(32 - (n))); ret; })
111 #endif
112 #if __riscv_xlen == 32
113 #undef ROTATE
114 #define ROTATE(x, n) ({ MD32_REG_T ret;            \
115                        asm ("rori %0, %1, %2"         \
116                        : "=r"(ret)                    \
117                        : "r"(x), "i"(32 - (n))); ret; })
118 #endif
119 #endif
120 #endif
121 #endif
122 
123 #if defined(DATA_ORDER_IS_BIG_ENDIAN)
124 
125 #define HOST_c2l(c, l) (l = (((unsigned long)(*((c)++))) << 24), \
126     l |= (((unsigned long)(*((c)++))) << 16),                    \
127     l |= (((unsigned long)(*((c)++))) << 8),                     \
128     l |= (((unsigned long)(*((c)++)))))
129 #define HOST_l2c(l, c) (*((c)++) = (unsigned char)(((l) >> 24) & 0xff), \
130     *((c)++) = (unsigned char)(((l) >> 16) & 0xff),                     \
131     *((c)++) = (unsigned char)(((l) >> 8) & 0xff),                      \
132     *((c)++) = (unsigned char)(((l)) & 0xff),                           \
133     l)
134 
135 #elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)
136 
137 #define HOST_c2l(c, l) (l = (((unsigned long)(*((c)++)))), \
138     l |= (((unsigned long)(*((c)++))) << 8),               \
139     l |= (((unsigned long)(*((c)++))) << 16),              \
140     l |= (((unsigned long)(*((c)++))) << 24))
141 #define HOST_l2c(l, c) (*((c)++) = (unsigned char)(((l)) & 0xff), \
142     *((c)++) = (unsigned char)(((l) >> 8) & 0xff),                \
143     *((c)++) = (unsigned char)(((l) >> 16) & 0xff),               \
144     *((c)++) = (unsigned char)(((l) >> 24) & 0xff),               \
145     l)
146 
147 #endif
148 
149 /*
150  * Time for some action :-)
151  */
152 
HASH_UPDATE(HASH_CTX * c,const void * data_,size_t len)153 int HASH_UPDATE(HASH_CTX *c, const void *data_, size_t len)
154 {
155     const unsigned char *data = data_;
156     unsigned char *p;
157     HASH_LONG l;
158     size_t n;
159 
160     if (len == 0)
161         return 1;
162 
163     l = (c->Nl + (((HASH_LONG)len) << 3)) & 0xffffffffUL;
164     if (l < c->Nl) /* overflow */
165         c->Nh++;
166     c->Nh += (HASH_LONG)(len >> 29); /* might cause compiler warning on
167                                       * 16-bit */
168     c->Nl = l;
169 
170     n = c->num;
171     if (n != 0) {
172         p = (unsigned char *)c->data;
173 
174         if (len >= HASH_CBLOCK || len + n >= HASH_CBLOCK) {
175             memcpy(p + n, data, HASH_CBLOCK - n);
176             HASH_BLOCK_DATA_ORDER(c, p, 1);
177             n = HASH_CBLOCK - n;
178             data += n;
179             len -= n;
180             c->num = 0;
181             /*
182              * We use memset rather than OPENSSL_cleanse() here deliberately.
183              * Using OPENSSL_cleanse() here could be a performance issue. It
184              * will get properly cleansed on finalisation so this isn't a
185              * security problem.
186              */
187             memset(p, 0, HASH_CBLOCK); /* keep it zeroed */
188         } else {
189             memcpy(p + n, data, len);
190             c->num += (unsigned int)len;
191             return 1;
192         }
193     }
194 
195     n = len / HASH_CBLOCK;
196     if (n > 0) {
197         HASH_BLOCK_DATA_ORDER(c, data, n);
198         n *= HASH_CBLOCK;
199         data += n;
200         len -= n;
201     }
202 
203     if (len != 0) {
204         p = (unsigned char *)c->data;
205         c->num = (unsigned int)len;
206         memcpy(p, data, len);
207     }
208     return 1;
209 }
210 
HASH_TRANSFORM(HASH_CTX * c,const unsigned char * data)211 void HASH_TRANSFORM(HASH_CTX *c, const unsigned char *data)
212 {
213     HASH_BLOCK_DATA_ORDER(c, data, 1);
214 }
215 
HASH_FINAL(unsigned char * md,HASH_CTX * c)216 int HASH_FINAL(unsigned char *md, HASH_CTX *c)
217 {
218     unsigned char *p = (unsigned char *)c->data;
219     size_t n = c->num;
220 
221     p[n] = 0x80; /* there is always room for one */
222     n++;
223 
224     if (n > (HASH_CBLOCK - 8)) {
225         memset(p + n, 0, HASH_CBLOCK - n);
226         n = 0;
227         HASH_BLOCK_DATA_ORDER(c, p, 1);
228     }
229     memset(p + n, 0, HASH_CBLOCK - 8 - n);
230 
231     p += HASH_CBLOCK - 8;
232 #if defined(DATA_ORDER_IS_BIG_ENDIAN)
233     (void)HOST_l2c(c->Nh, p);
234     (void)HOST_l2c(c->Nl, p);
235 #elif defined(DATA_ORDER_IS_LITTLE_ENDIAN)
236     (void)HOST_l2c(c->Nl, p);
237     (void)HOST_l2c(c->Nh, p);
238 #endif
239     p -= HASH_CBLOCK;
240     HASH_BLOCK_DATA_ORDER(c, p, 1);
241     c->num = 0;
242     OPENSSL_cleanse(p, HASH_CBLOCK);
243 
244 #ifndef HASH_MAKE_STRING
245 #error "HASH_MAKE_STRING must be defined!"
246 #else
247     HASH_MAKE_STRING(c, md);
248 #endif
249 
250     return 1;
251 }
252 
253 #ifndef MD32_REG_T
254 #if defined(__alpha) || defined(__sparcv9) || defined(__mips)
255 #define MD32_REG_T long
256 /*
257  * This comment was originally written for MD5, which is why it
258  * discusses A-D. But it basically applies to all 32-bit digests,
259  * which is why it was moved to common header file.
260  *
261  * In case you wonder why A-D are declared as long and not
262  * as MD5_LONG. Doing so results in slight performance
263  * boost on LP64 architectures. The catch is we don't
264  * really care if 32 MSBs of a 64-bit register get polluted
265  * with eventual overflows as we *save* only 32 LSBs in
266  * *either* case. Now declaring 'em long excuses the compiler
267  * from keeping 32 MSBs zeroed resulting in 13% performance
268  * improvement under SPARC Solaris7/64 and 5% under AlphaLinux.
269  * Well, to be honest it should say that this *prevents*
270  * performance degradation.
271  */
272 #else
273 /*
274  * Above is not absolute and there are LP64 compilers that
275  * generate better code if MD32_REG_T is defined int. The above
276  * pre-processor condition reflects the circumstances under which
277  * the conclusion was made and is subject to further extension.
278  */
279 #define MD32_REG_T int
280 #endif
281 #endif
282 
283 #endif
284