LLVM  3.7.0
FuzzerSHA1.cpp
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1 //===- FuzzerSHA1.h - Private copy of the SHA1 implementation ---*- C++ -* ===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 // This code is taken from public domain
10 // (http://oauth.googlecode.com/svn/code/c/liboauth/src/sha1.c)
11 // and modified by adding anonymous namespace, adding an interface
12 // function fuzzer::ComputeSHA1() and removing unnecessary code.
13 //
14 // lib/Fuzzer can not use SHA1 implementation from openssl because
15 // openssl may not be available and because we may be fuzzing openssl itself.
16 // For the same reason we do not want to depend on SHA1 from LLVM tree.
17 //===----------------------------------------------------------------------===//
18 
19 #include "FuzzerInternal.h"
20 
21 /* This code is public-domain - it is based on libcrypt
22  * placed in the public domain by Wei Dai and other contributors.
23  */
24 
25 #include <stdint.h>
26 #include <string.h>
27 
28 namespace { // Added for LibFuzzer
29 
30 #ifdef __BIG_ENDIAN__
31 # define SHA_BIG_ENDIAN
32 #elif defined __LITTLE_ENDIAN__
33 /* override */
34 #elif defined __BYTE_ORDER
35 # if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
36 # define SHA_BIG_ENDIAN
37 # endif
38 #else // ! defined __LITTLE_ENDIAN__
39 # include <endian.h> // machine/endian.h
40 # if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
41 # define SHA_BIG_ENDIAN
42 # endif
43 #endif
44 
45 
46 /* header */
47 
48 #define HASH_LENGTH 20
49 #define BLOCK_LENGTH 64
50 
51 typedef struct sha1nfo {
52  uint32_t buffer[BLOCK_LENGTH/4];
53  uint32_t state[HASH_LENGTH/4];
54  uint32_t byteCount;
55  uint8_t bufferOffset;
56  uint8_t keyBuffer[BLOCK_LENGTH];
57  uint8_t innerHash[HASH_LENGTH];
58 } sha1nfo;
59 
60 /* public API - prototypes - TODO: doxygen*/
61 
62 /**
63  */
64 void sha1_init(sha1nfo *s);
65 /**
66  */
67 void sha1_writebyte(sha1nfo *s, uint8_t data);
68 /**
69  */
70 void sha1_write(sha1nfo *s, const char *data, size_t len);
71 /**
72  */
73 uint8_t* sha1_result(sha1nfo *s);
74 
75 
76 /* code */
77 #define SHA1_K0 0x5a827999
78 #define SHA1_K20 0x6ed9eba1
79 #define SHA1_K40 0x8f1bbcdc
80 #define SHA1_K60 0xca62c1d6
81 
82 void sha1_init(sha1nfo *s) {
83  s->state[0] = 0x67452301;
84  s->state[1] = 0xefcdab89;
85  s->state[2] = 0x98badcfe;
86  s->state[3] = 0x10325476;
87  s->state[4] = 0xc3d2e1f0;
88  s->byteCount = 0;
89  s->bufferOffset = 0;
90 }
91 
92 uint32_t sha1_rol32(uint32_t number, uint8_t bits) {
93  return ((number << bits) | (number >> (32-bits)));
94 }
95 
96 void sha1_hashBlock(sha1nfo *s) {
97  uint8_t i;
98  uint32_t a,b,c,d,e,t;
99 
100  a=s->state[0];
101  b=s->state[1];
102  c=s->state[2];
103  d=s->state[3];
104  e=s->state[4];
105  for (i=0; i<80; i++) {
106  if (i>=16) {
107  t = s->buffer[(i+13)&15] ^ s->buffer[(i+8)&15] ^ s->buffer[(i+2)&15] ^ s->buffer[i&15];
108  s->buffer[i&15] = sha1_rol32(t,1);
109  }
110  if (i<20) {
111  t = (d ^ (b & (c ^ d))) + SHA1_K0;
112  } else if (i<40) {
113  t = (b ^ c ^ d) + SHA1_K20;
114  } else if (i<60) {
115  t = ((b & c) | (d & (b | c))) + SHA1_K40;
116  } else {
117  t = (b ^ c ^ d) + SHA1_K60;
118  }
119  t+=sha1_rol32(a,5) + e + s->buffer[i&15];
120  e=d;
121  d=c;
122  c=sha1_rol32(b,30);
123  b=a;
124  a=t;
125  }
126  s->state[0] += a;
127  s->state[1] += b;
128  s->state[2] += c;
129  s->state[3] += d;
130  s->state[4] += e;
131 }
132 
133 void sha1_addUncounted(sha1nfo *s, uint8_t data) {
134  uint8_t * const b = (uint8_t*) s->buffer;
135 #ifdef SHA_BIG_ENDIAN
136  b[s->bufferOffset] = data;
137 #else
138  b[s->bufferOffset ^ 3] = data;
139 #endif
140  s->bufferOffset++;
141  if (s->bufferOffset == BLOCK_LENGTH) {
142  sha1_hashBlock(s);
143  s->bufferOffset = 0;
144  }
145 }
146 
147 void sha1_writebyte(sha1nfo *s, uint8_t data) {
148  ++s->byteCount;
149  sha1_addUncounted(s, data);
150 }
151 
152 void sha1_write(sha1nfo *s, const char *data, size_t len) {
153  for (;len--;) sha1_writebyte(s, (uint8_t) *data++);
154 }
155 
156 void sha1_pad(sha1nfo *s) {
157  // Implement SHA-1 padding (fips180-2 ยง5.1.1)
158 
159  // Pad with 0x80 followed by 0x00 until the end of the block
160  sha1_addUncounted(s, 0x80);
161  while (s->bufferOffset != 56) sha1_addUncounted(s, 0x00);
162 
163  // Append length in the last 8 bytes
164  sha1_addUncounted(s, 0); // We're only using 32 bit lengths
165  sha1_addUncounted(s, 0); // But SHA-1 supports 64 bit lengths
166  sha1_addUncounted(s, 0); // So zero pad the top bits
167  sha1_addUncounted(s, s->byteCount >> 29); // Shifting to multiply by 8
168  sha1_addUncounted(s, s->byteCount >> 21); // as SHA-1 supports bitstreams as well as
169  sha1_addUncounted(s, s->byteCount >> 13); // byte.
170  sha1_addUncounted(s, s->byteCount >> 5);
171  sha1_addUncounted(s, s->byteCount << 3);
172 }
173 
174 uint8_t* sha1_result(sha1nfo *s) {
175  // Pad to complete the last block
176  sha1_pad(s);
177 
178 #ifndef SHA_BIG_ENDIAN
179  // Swap byte order back
180  int i;
181  for (i=0; i<5; i++) {
182  s->state[i]=
183  (((s->state[i])<<24)& 0xff000000)
184  | (((s->state[i])<<8) & 0x00ff0000)
185  | (((s->state[i])>>8) & 0x0000ff00)
186  | (((s->state[i])>>24)& 0x000000ff);
187  }
188 #endif
189 
190  // Return pointer to hash (20 characters)
191  return (uint8_t*) s->state;
192 }
193 
194 } // namespace; Added for LibFuzzer
195 
196 // The rest is added for LibFuzzer
197 void fuzzer::ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out) {
198  sha1nfo s;
199  sha1_init(&s);
200  sha1_write(&s, (const char*)Data, Len);
201  memcpy(Out, sha1_result(&s), HASH_LENGTH);
202 }
#define BLOCK_LENGTH
Definition: FuzzerSHA1.cpp:49
#define SHA1_K20
Definition: FuzzerSHA1.cpp:78
#define SHA_BIG_ENDIAN
Definition: FuzzerSHA1.cpp:41
#define SHA1_K40
Definition: FuzzerSHA1.cpp:79
void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out)
Definition: FuzzerSHA1.cpp:197
* if(!EatIfPresent(lltok::kw_thread_local)) return false
ParseOptionalThreadLocal := /*empty.
#define SHA1_K60
Definition: FuzzerSHA1.cpp:80
#define SHA1_K0
Definition: FuzzerSHA1.cpp:77
#define HASH_LENGTH
Definition: FuzzerSHA1.cpp:48