GNU libmicrohttpd  0.9.75
sha1.c
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1 /*
2  This file is part of libmicrohttpd
3  Copyright (C) 2019-2021 Karlson2k (Evgeny Grin)
4 
5  libmicrohttpd is free software; you can redistribute it and/or
6  modify it under the terms of the GNU Lesser General Public
7  License as published by the Free Software Foundation; either
8  version 2.1 of the License, or (at your option) any later version.
9 
10  This library is distributed in the hope that it will be useful,
11  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Lesser General Public License for more details.
14 
15  You should have received a copy of the GNU Lesser General Public
16  License along with this library.
17  If not, see <http://www.gnu.org/licenses/>.
18 */
19 
26 #include "sha1.h"
27 
28 #include <string.h>
29 #ifdef HAVE_MEMORY_H
30 #include <memory.h>
31 #endif /* HAVE_MEMORY_H */
32 #include "mhd_bithelpers.h"
33 #include "mhd_assert.h"
34 
40 void
41 MHD_SHA1_init (void *ctx_)
42 {
43  struct sha1_ctx *const ctx = ctx_;
44  /* Initial hash values, see FIPS PUB 180-4 paragraph 5.3.1 */
45  /* Just some "magic" numbers defined by standard */
46  ctx->H[0] = UINT32_C (0x67452301);
47  ctx->H[1] = UINT32_C (0xefcdab89);
48  ctx->H[2] = UINT32_C (0x98badcfe);
49  ctx->H[3] = UINT32_C (0x10325476);
50  ctx->H[4] = UINT32_C (0xc3d2e1f0);
51 
52  /* Initialise number of bytes. */
53  ctx->count = 0;
54 }
55 
56 
63 static void
65  const uint8_t data[SHA1_BLOCK_SIZE])
66 {
67  /* Working variables,
68  see FIPS PUB 180-4 paragraph 6.1.3 */
69  uint32_t a = H[0];
70  uint32_t b = H[1];
71  uint32_t c = H[2];
72  uint32_t d = H[3];
73  uint32_t e = H[4];
74 
75  /* Data buffer, used as cyclic buffer.
76  See FIPS PUB 180-4 paragraphs 5.2.1, 6.1.3 */
77  uint32_t W[16];
78 
79  /* 'Ch' and 'Maj' macro functions are defined with
80  widely-used optimization.
81  See FIPS PUB 180-4 formulae 4.1. */
82 #define Ch(x,y,z) ( (z) ^ ((x) & ((y) ^ (z))) )
83 #define Maj(x,y,z) ( ((x) & (y)) ^ ((z) & ((x) ^ (y))) )
84  /* Unoptimized (original) versions: */
85 /* #define Ch(x,y,z) ( ( (x) & (y) ) ^ ( ~(x) & (z) ) ) */
86 /* #define Maj(x,y,z) ( ((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)) ) */
87 #define Par(x,y,z) ( (x) ^ (y) ^ (z) )
88 
89  /* Single step of SHA-1 computation,
90  see FIPS PUB 180-4 paragraph 6.1.3 step 3.
91  * Note: instead of reassigning all working variables on each step,
92  variables are rotated for each step:
93  SHA1STEP32 (a, b, c, d, e, func, K00, W[0]);
94  SHA1STEP32 (e, a, b, c, d, func, K00, W[1]);
95  so current 'vC' will be used as 'vD' on the next step,
96  current 'vE' will be used as 'vA' on the next step.
97  * Note: 'wt' must be used exactly one time in this macro as it change other data as well
98  every time when used. */
99 
100 #define SHA1STEP32(vA,vB,vC,vD,vE,ft,kt,wt) do { \
101  (vE) += _MHD_ROTL32 ((vA), 5) + ft ((vB), (vC), (vD)) + (kt) + (wt); \
102  (vB) = _MHD_ROTL32 ((vB), 30); } while (0)
103 
104  /* Get value of W(t) from input data buffer,
105  See FIPS PUB 180-4 paragraph 6.1.3.
106  Input data must be read in big-endian bytes order,
107  see FIPS PUB 180-4 paragraph 3.1.2. */
108 #define GET_W_FROM_DATA(buf,t) \
109  _MHD_GET_32BIT_BE (((const uint8_t*) (buf)) + (t) * SHA1_BYTES_IN_WORD)
110 
111 #ifndef _MHD_GET_32BIT_BE_UNALIGNED
112  if (0 != (((uintptr_t) data) % _MHD_UINT32_ALIGN))
113  {
114  /* Copy the unaligned input data to the aligned buffer */
115  memcpy (W, data, SHA1_BLOCK_SIZE);
116  /* The W[] buffer itself will be used as the source of the data,
117  * but data will be reloaded in correct bytes order during
118  * the next steps */
119  data = (uint8_t*) W;
120  }
121 #endif /* _MHD_GET_32BIT_BE_UNALIGNED */
122 
123 /* SHA-1 values of Kt for t=0..19, see FIPS PUB 180-4 paragraph 4.2.1. */
124 #define K00 UINT32_C(0x5a827999)
125 /* SHA-1 values of Kt for t=20..39, see FIPS PUB 180-4 paragraph 4.2.1.*/
126 #define K20 UINT32_C(0x6ed9eba1)
127 /* SHA-1 values of Kt for t=40..59, see FIPS PUB 180-4 paragraph 4.2.1.*/
128 #define K40 UINT32_C(0x8f1bbcdc)
129 /* SHA-1 values of Kt for t=60..79, see FIPS PUB 180-4 paragraph 4.2.1.*/
130 #define K60 UINT32_C(0xca62c1d6)
131 
132  /* During first 16 steps, before making any calculations on each step,
133  the W element is read from input data buffer as big-endian value and
134  stored in array of W elements. */
135  /* Note: instead of using K constants as array, all K values are specified
136  individually for each step. */
137  SHA1STEP32 (a, b, c, d, e, Ch, K00, W[0] = GET_W_FROM_DATA (data, 0));
138  SHA1STEP32 (e, a, b, c, d, Ch, K00, W[1] = GET_W_FROM_DATA (data, 1));
139  SHA1STEP32 (d, e, a, b, c, Ch, K00, W[2] = GET_W_FROM_DATA (data, 2));
140  SHA1STEP32 (c, d, e, a, b, Ch, K00, W[3] = GET_W_FROM_DATA (data, 3));
141  SHA1STEP32 (b, c, d, e, a, Ch, K00, W[4] = GET_W_FROM_DATA (data, 4));
142  SHA1STEP32 (a, b, c, d, e, Ch, K00, W[5] = GET_W_FROM_DATA (data, 5));
143  SHA1STEP32 (e, a, b, c, d, Ch, K00, W[6] = GET_W_FROM_DATA (data, 6));
144  SHA1STEP32 (d, e, a, b, c, Ch, K00, W[7] = GET_W_FROM_DATA (data, 7));
145  SHA1STEP32 (c, d, e, a, b, Ch, K00, W[8] = GET_W_FROM_DATA (data, 8));
146  SHA1STEP32 (b, c, d, e, a, Ch, K00, W[9] = GET_W_FROM_DATA (data, 9));
147  SHA1STEP32 (a, b, c, d, e, Ch, K00, W[10] = GET_W_FROM_DATA (data, 10));
148  SHA1STEP32 (e, a, b, c, d, Ch, K00, W[11] = GET_W_FROM_DATA (data, 11));
149  SHA1STEP32 (d, e, a, b, c, Ch, K00, W[12] = GET_W_FROM_DATA (data, 12));
150  SHA1STEP32 (c, d, e, a, b, Ch, K00, W[13] = GET_W_FROM_DATA (data, 13));
151  SHA1STEP32 (b, c, d, e, a, Ch, K00, W[14] = GET_W_FROM_DATA (data, 14));
152  SHA1STEP32 (a, b, c, d, e, Ch, K00, W[15] = GET_W_FROM_DATA (data, 15));
153 
154  /* 'W' generation and assignment for 16 <= t <= 79.
155  See FIPS PUB 180-4 paragraph 6.1.3.
156  As only last 16 'W' are used in calculations, it is possible to
157  use 16 elements array of W as cyclic buffer. */
158 #define Wgen(w,t) _MHD_ROTL32((w)[(t + 13) & 0xf] ^ (w)[(t + 8) & 0xf] \
159  ^ (w)[(t + 2) & 0xf] ^ (w)[t & 0xf], 1)
160 
161  /* During last 60 steps, before making any calculations on each step,
162  W element is generated from W elements of cyclic buffer and generated value
163  stored back in cyclic buffer. */
164  /* Note: instead of using K constants as array, all K values are specified
165  individually for each step, see FIPS PUB 180-4 paragraph 4.2.1. */
166  SHA1STEP32 (e, a, b, c, d, Ch, K00, W[16 & 0xf] = Wgen (W, 16));
167  SHA1STEP32 (d, e, a, b, c, Ch, K00, W[17 & 0xf] = Wgen (W, 17));
168  SHA1STEP32 (c, d, e, a, b, Ch, K00, W[18 & 0xf] = Wgen (W, 18));
169  SHA1STEP32 (b, c, d, e, a, Ch, K00, W[19 & 0xf] = Wgen (W, 19));
170  SHA1STEP32 (a, b, c, d, e, Par, K20, W[20 & 0xf] = Wgen (W, 20));
171  SHA1STEP32 (e, a, b, c, d, Par, K20, W[21 & 0xf] = Wgen (W, 21));
172  SHA1STEP32 (d, e, a, b, c, Par, K20, W[22 & 0xf] = Wgen (W, 22));
173  SHA1STEP32 (c, d, e, a, b, Par, K20, W[23 & 0xf] = Wgen (W, 23));
174  SHA1STEP32 (b, c, d, e, a, Par, K20, W[24 & 0xf] = Wgen (W, 24));
175  SHA1STEP32 (a, b, c, d, e, Par, K20, W[25 & 0xf] = Wgen (W, 25));
176  SHA1STEP32 (e, a, b, c, d, Par, K20, W[26 & 0xf] = Wgen (W, 26));
177  SHA1STEP32 (d, e, a, b, c, Par, K20, W[27 & 0xf] = Wgen (W, 27));
178  SHA1STEP32 (c, d, e, a, b, Par, K20, W[28 & 0xf] = Wgen (W, 28));
179  SHA1STEP32 (b, c, d, e, a, Par, K20, W[29 & 0xf] = Wgen (W, 29));
180  SHA1STEP32 (a, b, c, d, e, Par, K20, W[30 & 0xf] = Wgen (W, 30));
181  SHA1STEP32 (e, a, b, c, d, Par, K20, W[31 & 0xf] = Wgen (W, 31));
182  SHA1STEP32 (d, e, a, b, c, Par, K20, W[32 & 0xf] = Wgen (W, 32));
183  SHA1STEP32 (c, d, e, a, b, Par, K20, W[33 & 0xf] = Wgen (W, 33));
184  SHA1STEP32 (b, c, d, e, a, Par, K20, W[34 & 0xf] = Wgen (W, 34));
185  SHA1STEP32 (a, b, c, d, e, Par, K20, W[35 & 0xf] = Wgen (W, 35));
186  SHA1STEP32 (e, a, b, c, d, Par, K20, W[36 & 0xf] = Wgen (W, 36));
187  SHA1STEP32 (d, e, a, b, c, Par, K20, W[37 & 0xf] = Wgen (W, 37));
188  SHA1STEP32 (c, d, e, a, b, Par, K20, W[38 & 0xf] = Wgen (W, 38));
189  SHA1STEP32 (b, c, d, e, a, Par, K20, W[39 & 0xf] = Wgen (W, 39));
190  SHA1STEP32 (a, b, c, d, e, Maj, K40, W[40 & 0xf] = Wgen (W, 40));
191  SHA1STEP32 (e, a, b, c, d, Maj, K40, W[41 & 0xf] = Wgen (W, 41));
192  SHA1STEP32 (d, e, a, b, c, Maj, K40, W[42 & 0xf] = Wgen (W, 42));
193  SHA1STEP32 (c, d, e, a, b, Maj, K40, W[43 & 0xf] = Wgen (W, 43));
194  SHA1STEP32 (b, c, d, e, a, Maj, K40, W[44 & 0xf] = Wgen (W, 44));
195  SHA1STEP32 (a, b, c, d, e, Maj, K40, W[45 & 0xf] = Wgen (W, 45));
196  SHA1STEP32 (e, a, b, c, d, Maj, K40, W[46 & 0xf] = Wgen (W, 46));
197  SHA1STEP32 (d, e, a, b, c, Maj, K40, W[47 & 0xf] = Wgen (W, 47));
198  SHA1STEP32 (c, d, e, a, b, Maj, K40, W[48 & 0xf] = Wgen (W, 48));
199  SHA1STEP32 (b, c, d, e, a, Maj, K40, W[49 & 0xf] = Wgen (W, 49));
200  SHA1STEP32 (a, b, c, d, e, Maj, K40, W[50 & 0xf] = Wgen (W, 50));
201  SHA1STEP32 (e, a, b, c, d, Maj, K40, W[51 & 0xf] = Wgen (W, 51));
202  SHA1STEP32 (d, e, a, b, c, Maj, K40, W[52 & 0xf] = Wgen (W, 52));
203  SHA1STEP32 (c, d, e, a, b, Maj, K40, W[53 & 0xf] = Wgen (W, 53));
204  SHA1STEP32 (b, c, d, e, a, Maj, K40, W[54 & 0xf] = Wgen (W, 54));
205  SHA1STEP32 (a, b, c, d, e, Maj, K40, W[55 & 0xf] = Wgen (W, 55));
206  SHA1STEP32 (e, a, b, c, d, Maj, K40, W[56 & 0xf] = Wgen (W, 56));
207  SHA1STEP32 (d, e, a, b, c, Maj, K40, W[57 & 0xf] = Wgen (W, 57));
208  SHA1STEP32 (c, d, e, a, b, Maj, K40, W[58 & 0xf] = Wgen (W, 58));
209  SHA1STEP32 (b, c, d, e, a, Maj, K40, W[59 & 0xf] = Wgen (W, 59));
210  SHA1STEP32 (a, b, c, d, e, Par, K60, W[60 & 0xf] = Wgen (W, 60));
211  SHA1STEP32 (e, a, b, c, d, Par, K60, W[61 & 0xf] = Wgen (W, 61));
212  SHA1STEP32 (d, e, a, b, c, Par, K60, W[62 & 0xf] = Wgen (W, 62));
213  SHA1STEP32 (c, d, e, a, b, Par, K60, W[63 & 0xf] = Wgen (W, 63));
214  SHA1STEP32 (b, c, d, e, a, Par, K60, W[64 & 0xf] = Wgen (W, 64));
215  SHA1STEP32 (a, b, c, d, e, Par, K60, W[65 & 0xf] = Wgen (W, 65));
216  SHA1STEP32 (e, a, b, c, d, Par, K60, W[66 & 0xf] = Wgen (W, 66));
217  SHA1STEP32 (d, e, a, b, c, Par, K60, W[67 & 0xf] = Wgen (W, 67));
218  SHA1STEP32 (c, d, e, a, b, Par, K60, W[68 & 0xf] = Wgen (W, 68));
219  SHA1STEP32 (b, c, d, e, a, Par, K60, W[69 & 0xf] = Wgen (W, 69));
220  SHA1STEP32 (a, b, c, d, e, Par, K60, W[70 & 0xf] = Wgen (W, 70));
221  SHA1STEP32 (e, a, b, c, d, Par, K60, W[71 & 0xf] = Wgen (W, 71));
222  SHA1STEP32 (d, e, a, b, c, Par, K60, W[72 & 0xf] = Wgen (W, 72));
223  SHA1STEP32 (c, d, e, a, b, Par, K60, W[73 & 0xf] = Wgen (W, 73));
224  SHA1STEP32 (b, c, d, e, a, Par, K60, W[74 & 0xf] = Wgen (W, 74));
225  SHA1STEP32 (a, b, c, d, e, Par, K60, W[75 & 0xf] = Wgen (W, 75));
226  SHA1STEP32 (e, a, b, c, d, Par, K60, W[76 & 0xf] = Wgen (W, 76));
227  SHA1STEP32 (d, e, a, b, c, Par, K60, W[77 & 0xf] = Wgen (W, 77));
228  SHA1STEP32 (c, d, e, a, b, Par, K60, W[78 & 0xf] = Wgen (W, 78));
229  SHA1STEP32 (b, c, d, e, a, Par, K60, W[79 & 0xf] = Wgen (W, 79));
230 
231  /* Compute intermediate hash.
232  See FIPS PUB 180-4 paragraph 6.1.3 step 4. */
233  H[0] += a;
234  H[1] += b;
235  H[2] += c;
236  H[3] += d;
237  H[4] += e;
238 }
239 
240 
248 void
249 MHD_SHA1_update (void *ctx_,
250  const uint8_t *data,
251  size_t length)
252 {
253  struct sha1_ctx *const ctx = ctx_;
254  unsigned bytes_have;
256  mhd_assert ((data != NULL) || (length == 0));
257 
258  if (0 == length)
259  return; /* Do nothing */
260 
261  /* Note: (count & (SHA1_BLOCK_SIZE-1))
262  equal (count % SHA1_BLOCK_SIZE) for this block size. */
263  bytes_have = (unsigned) (ctx->count & (SHA1_BLOCK_SIZE - 1));
264  ctx->count += length;
265 
266  if (0 != bytes_have)
267  {
268  unsigned bytes_left = SHA1_BLOCK_SIZE - bytes_have;
269  if (length >= bytes_left)
270  { /* Combine new data with the data in the buffer and
271  process the full block. */
272  memcpy (ctx->buffer + bytes_have,
273  data,
274  bytes_left);
275  data += bytes_left;
276  length -= bytes_left;
277  sha1_transform (ctx->H, ctx->buffer);
278  bytes_have = 0;
279  }
280  }
281 
282  while (SHA1_BLOCK_SIZE <= length)
283  { /* Process any full blocks of new data directly,
284  without copying to the buffer. */
285  sha1_transform (ctx->H, data);
287  length -= SHA1_BLOCK_SIZE;
288  }
289 
290  if (0 != length)
291  { /* Copy incomplete block of new data (if any)
292  to the buffer. */
293  memcpy (ctx->buffer + bytes_have, data, length);
294  }
295 }
296 
297 
302 #define SHA1_SIZE_OF_LEN_ADD (64 / 8)
303 
310 void
311 MHD_SHA1_finish (void *ctx_,
312  uint8_t digest[SHA1_DIGEST_SIZE])
313 {
314  struct sha1_ctx *const ctx = ctx_;
315  uint64_t num_bits;
316  unsigned bytes_have;
318  num_bits = ctx->count << 3;
319  /* Note: (count & (SHA1_BLOCK_SIZE-1))
320  equals (count % SHA1_BLOCK_SIZE) for this block size. */
321  bytes_have = (unsigned) (ctx->count & (SHA1_BLOCK_SIZE - 1));
322 
323  /* Input data must be padded with bit "1" and with length of data in bits.
324  See FIPS PUB 180-4 paragraph 5.1.1. */
325  /* Data is always processed in form of bytes (not by individual bits),
326  therefore position of first padding bit in byte is always predefined (0x80). */
327  /* Buffer always have space at least for one byte (as full buffers are
328  processed immediately). */
329  ctx->buffer[bytes_have++] = 0x80;
330 
331  if (SHA1_BLOCK_SIZE - bytes_have < SHA1_SIZE_OF_LEN_ADD)
332  { /* No space in current block to put total length of message.
333  Pad current block with zeros and process it. */
334  if (SHA1_BLOCK_SIZE > bytes_have)
335  memset (ctx->buffer + bytes_have, 0, SHA1_BLOCK_SIZE - bytes_have);
336  /* Process full block. */
337  sha1_transform (ctx->H, ctx->buffer);
338  /* Start new block. */
339  bytes_have = 0;
340  }
341 
342  /* Pad the rest of the buffer with zeros. */
343  memset (ctx->buffer + bytes_have, 0,
344  SHA1_BLOCK_SIZE - SHA1_SIZE_OF_LEN_ADD - bytes_have);
345  /* Put the number of bits in the processed message as a big-endian value. */
347  num_bits);
348  /* Process the full final block. */
349  sha1_transform (ctx->H, ctx->buffer);
350 
351  /* Put final hash/digest in BE mode */
352 #ifndef _MHD_PUT_32BIT_BE_UNALIGNED
353  if (0 != ((uintptr_t) digest) % _MHD_UINT32_ALIGN)
354  {
355  uint32_t alig_dgst[_SHA1_DIGEST_LENGTH];
356  _MHD_PUT_32BIT_BE (alig_dgst + 0, ctx->H[0]);
357  _MHD_PUT_32BIT_BE (alig_dgst + 1, ctx->H[1]);
358  _MHD_PUT_32BIT_BE (alig_dgst + 2, ctx->H[2]);
359  _MHD_PUT_32BIT_BE (alig_dgst + 3, ctx->H[3]);
360  _MHD_PUT_32BIT_BE (alig_dgst + 4, ctx->H[4]);
361  /* Copy result to unaligned destination address */
362  memcpy (digest, alig_dgst, SHA1_DIGEST_SIZE);
363  }
364  else
365 #else /* _MHD_PUT_32BIT_BE_UNALIGNED */
366  if (1)
367 #endif /* _MHD_PUT_32BIT_BE_UNALIGNED */
368  {
369  _MHD_PUT_32BIT_BE (digest + 0 * SHA1_BYTES_IN_WORD, ctx->H[0]);
370  _MHD_PUT_32BIT_BE (digest + 1 * SHA1_BYTES_IN_WORD, ctx->H[1]);
371  _MHD_PUT_32BIT_BE (digest + 2 * SHA1_BYTES_IN_WORD, ctx->H[2]);
372  _MHD_PUT_32BIT_BE (digest + 3 * SHA1_BYTES_IN_WORD, ctx->H[3]);
373  _MHD_PUT_32BIT_BE (digest + 4 * SHA1_BYTES_IN_WORD, ctx->H[4]);
374  }
375 
376  /* Erase potentially sensitive data. */
377  memset (ctx, 0, sizeof(struct sha1_ctx));
378 }
#define mhd_assert(CHK)
Definition: mhd_assert.h:39
#define NULL
Definition: reason_phrase.c:30
#define _MHD_UINT32_ALIGN
Definition: mhd_align.h:85
macros for bits manipulations
_MHD_static_inline void _MHD_PUT_64BIT_BE_SAFE(void *dst, uint64_t value)
#define _MHD_PUT_32BIT_BE(addr, value32)
macros for mhd_assert()
void MHD_SHA1_update(void *ctx_, const uint8_t *data, size_t length)
Definition: sha1.c:249
#define Wgen(w, t)
void MHD_SHA1_finish(void *ctx_, uint8_t digest[SHA1_DIGEST_SIZE])
Definition: sha1.c:311
#define K00
#define K40
#define Maj(x, y, z)
#define Par(x, y, z)
#define SHA1STEP32(vA, vB, vC, vD, vE, ft, kt, wt)
#define Ch(x, y, z)
void MHD_SHA1_init(void *ctx_)
Definition: sha1.c:41
#define K20
#define SHA1_SIZE_OF_LEN_ADD
Definition: sha1.c:302
#define GET_W_FROM_DATA(buf, t)
#define K60
static void sha1_transform(uint32_t H[_SHA1_DIGEST_LENGTH], const uint8_t data[SHA1_BLOCK_SIZE])
Definition: sha1.c:64
#define _SHA1_DIGEST_LENGTH
Definition: sha1.h:38
#define SHA1_DIGEST_SIZE
Definition: sha1.h:53
#define SHA1_BLOCK_SIZE
Definition: sha1.h:68
#define SHA1_BYTES_IN_WORD
Definition: sha1.h:48
void * data
Definition: microhttpd.h:3428
Definition: sha1.h:72
uint64_t count
Definition: sha1.h:75
uint32_t H[_SHA1_DIGEST_LENGTH]
Definition: sha1.h:73
uint8_t buffer[SHA1_BLOCK_SIZE]
Definition: sha1.h:74