LLVM  4.0.0
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 "FuzzerSHA1.h"
20 #include "FuzzerDefs.h"
21 
22 /* This code is public-domain - it is based on libcrypt
23  * placed in the public domain by Wei Dai and other contributors.
24  */
25 
26 #include <iomanip>
27 #include <sstream>
28 #include <stdint.h>
29 #include <string.h>
30 
31 namespace { // Added for LibFuzzer
32 
33 #ifdef __BIG_ENDIAN__
34 # define SHA_BIG_ENDIAN
35 #elif defined __LITTLE_ENDIAN__
36 /* override */
37 #elif defined __BYTE_ORDER
38 # if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
39 # define SHA_BIG_ENDIAN
40 # endif
41 #else // ! defined __LITTLE_ENDIAN__
42 # include <endian.h> // machine/endian.h
43 # if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
44 # define SHA_BIG_ENDIAN
45 # endif
46 #endif
47 
48 
49 /* header */
50 
51 #define HASH_LENGTH 20
52 #define BLOCK_LENGTH 64
53 
54 typedef struct sha1nfo {
55  uint32_t buffer[BLOCK_LENGTH/4];
56  uint32_t state[HASH_LENGTH/4];
57  uint32_t byteCount;
58  uint8_t bufferOffset;
59  uint8_t keyBuffer[BLOCK_LENGTH];
60  uint8_t innerHash[HASH_LENGTH];
61 } sha1nfo;
62 
63 /* public API - prototypes - TODO: doxygen*/
64 
65 /**
66  */
67 void sha1_init(sha1nfo *s);
68 /**
69  */
70 void sha1_writebyte(sha1nfo *s, uint8_t data);
71 /**
72  */
73 void sha1_write(sha1nfo *s, const char *data, size_t len);
74 /**
75  */
76 uint8_t* sha1_result(sha1nfo *s);
77 
78 
79 /* code */
80 #define SHA1_K0 0x5a827999
81 #define SHA1_K20 0x6ed9eba1
82 #define SHA1_K40 0x8f1bbcdc
83 #define SHA1_K60 0xca62c1d6
84 
85 void sha1_init(sha1nfo *s) {
86  s->state[0] = 0x67452301;
87  s->state[1] = 0xefcdab89;
88  s->state[2] = 0x98badcfe;
89  s->state[3] = 0x10325476;
90  s->state[4] = 0xc3d2e1f0;
91  s->byteCount = 0;
92  s->bufferOffset = 0;
93 }
94 
95 uint32_t sha1_rol32(uint32_t number, uint8_t bits) {
96  return ((number << bits) | (number >> (32-bits)));
97 }
98 
99 void sha1_hashBlock(sha1nfo *s) {
100  uint8_t i;
101  uint32_t a,b,c,d,e,t;
102 
103  a=s->state[0];
104  b=s->state[1];
105  c=s->state[2];
106  d=s->state[3];
107  e=s->state[4];
108  for (i=0; i<80; i++) {
109  if (i>=16) {
110  t = s->buffer[(i+13)&15] ^ s->buffer[(i+8)&15] ^ s->buffer[(i+2)&15] ^ s->buffer[i&15];
111  s->buffer[i&15] = sha1_rol32(t,1);
112  }
113  if (i<20) {
114  t = (d ^ (b & (c ^ d))) + SHA1_K0;
115  } else if (i<40) {
116  t = (b ^ c ^ d) + SHA1_K20;
117  } else if (i<60) {
118  t = ((b & c) | (d & (b | c))) + SHA1_K40;
119  } else {
120  t = (b ^ c ^ d) + SHA1_K60;
121  }
122  t+=sha1_rol32(a,5) + e + s->buffer[i&15];
123  e=d;
124  d=c;
125  c=sha1_rol32(b,30);
126  b=a;
127  a=t;
128  }
129  s->state[0] += a;
130  s->state[1] += b;
131  s->state[2] += c;
132  s->state[3] += d;
133  s->state[4] += e;
134 }
135 
136 void sha1_addUncounted(sha1nfo *s, uint8_t data) {
137  uint8_t * const b = (uint8_t*) s->buffer;
138 #ifdef SHA_BIG_ENDIAN
139  b[s->bufferOffset] = data;
140 #else
141  b[s->bufferOffset ^ 3] = data;
142 #endif
143  s->bufferOffset++;
144  if (s->bufferOffset == BLOCK_LENGTH) {
145  sha1_hashBlock(s);
146  s->bufferOffset = 0;
147  }
148 }
149 
150 void sha1_writebyte(sha1nfo *s, uint8_t data) {
151  ++s->byteCount;
152  sha1_addUncounted(s, data);
153 }
154 
155 void sha1_write(sha1nfo *s, const char *data, size_t len) {
156  for (;len--;) sha1_writebyte(s, (uint8_t) *data++);
157 }
158 
159 void sha1_pad(sha1nfo *s) {
160  // Implement SHA-1 padding (fips180-2 ยง5.1.1)
161 
162  // Pad with 0x80 followed by 0x00 until the end of the block
163  sha1_addUncounted(s, 0x80);
164  while (s->bufferOffset != 56) sha1_addUncounted(s, 0x00);
165 
166  // Append length in the last 8 bytes
167  sha1_addUncounted(s, 0); // We're only using 32 bit lengths
168  sha1_addUncounted(s, 0); // But SHA-1 supports 64 bit lengths
169  sha1_addUncounted(s, 0); // So zero pad the top bits
170  sha1_addUncounted(s, s->byteCount >> 29); // Shifting to multiply by 8
171  sha1_addUncounted(s, s->byteCount >> 21); // as SHA-1 supports bitstreams as well as
172  sha1_addUncounted(s, s->byteCount >> 13); // byte.
173  sha1_addUncounted(s, s->byteCount >> 5);
174  sha1_addUncounted(s, s->byteCount << 3);
175 }
176 
177 uint8_t* sha1_result(sha1nfo *s) {
178  // Pad to complete the last block
179  sha1_pad(s);
180 
181 #ifndef SHA_BIG_ENDIAN
182  // Swap byte order back
183  int i;
184  for (i=0; i<5; i++) {
185  s->state[i]=
186  (((s->state[i])<<24)& 0xff000000)
187  | (((s->state[i])<<8) & 0x00ff0000)
188  | (((s->state[i])>>8) & 0x0000ff00)
189  | (((s->state[i])>>24)& 0x000000ff);
190  }
191 #endif
192 
193  // Return pointer to hash (20 characters)
194  return (uint8_t*) s->state;
195 }
196 
197 } // namespace; Added for LibFuzzer
198 
199 namespace fuzzer {
200 
201 // The rest is added for LibFuzzer
202 void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out) {
203  sha1nfo s;
204  sha1_init(&s);
205  sha1_write(&s, (const char*)Data, Len);
206  memcpy(Out, sha1_result(&s), HASH_LENGTH);
207 }
208 
209 std::string Sha1ToString(const uint8_t Sha1[kSHA1NumBytes]) {
210  std::stringstream SS;
211  for (int i = 0; i < kSHA1NumBytes; i++)
212  SS << std::hex << std::setfill('0') << std::setw(2) << (unsigned)Sha1[i];
213  return SS.str();
214 }
215 
216 std::string Hash(const Unit &U) {
217  uint8_t Hash[kSHA1NumBytes];
218  ComputeSHA1(U.data(), U.size(), Hash);
219  return Sha1ToString(Hash);
220 }
221 
222 }
size_t i
#define BLOCK_LENGTH
Definition: FuzzerSHA1.cpp:52
demanded bits
#define SHA1_K20
Definition: FuzzerSHA1.cpp:81
#define SHA_BIG_ENDIAN
Definition: FuzzerSHA1.cpp:44
#define SHA1_K40
Definition: FuzzerSHA1.cpp:82
static F t[256]
void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out)
Definition: FuzzerSHA1.cpp:202
* if(!EatIfPresent(lltok::kw_thread_local)) return false
ParseOptionalThreadLocal := /*empty.
#define SHA1_K60
Definition: FuzzerSHA1.cpp:83
std::string Sha1ToString(const uint8_t Sha1[kSHA1NumBytes])
Definition: FuzzerSHA1.cpp:209
#define SHA1_K0
Definition: FuzzerSHA1.cpp:80
std::vector< uint8_t > Unit
Definition: FuzzerDefs.h:71
std::string Hash(const Unit &U)
Definition: FuzzerSHA1.cpp:216
#define HASH_LENGTH
Definition: FuzzerSHA1.cpp:51
static const int kSHA1NumBytes
Definition: FuzzerSHA1.h:22