Is there any tool that I could use offline to experiment on BTC's SHA-256 and both 160 hash functions on windows?
The easiest way is to write that tool in any programming language. Because some tools that are available, can give you the final hash, but won't let you see internal state of hash functions. And writing that is not hard: optimizing and making it fast enough for mining is hard, but if you are interested only in mathematical aspects of hash functions, then you can execute it round-by-round, and you don't need any optimizations, at least not at the beginning. Also, brute-forcing is not the way to go, so you are going to write some code anyway, if you want to get any of those coins.
Usually to understand hash functions, you don't need to go beyond a single block. That means, for SHA-256, you don't need longer messages than 512 bits if you want to try some simple attacks. The same for SHA-1, and for many other
Merkle–Damgård hash functions. Also, if you will have some short implementation of SHA-1, then you can easily change how it works, and see how those changes can propagate.
Some example of C++ implementation for SHA-1, with displaying internal status, round-by-round:
#include
#include
#include
#include
std::string toString32(std::uint32_t value)
{
std::ostringstream out;
out.width(8);
out.fill('0');
out< return out.str();
}
std::uint32_t rotateLeft(std::uint32_t value,std::size_t n)
{
return (value<<(n%32))|(value>>(32-(n%32)));
}
std::uint32_t f1(std::uint32_t b,std::uint32_t c,std::uint32_t d)
{
return (b&c)|((~b)&d);
}
std::uint32_t f2(std::uint32_t b,std::uint32_t c,std::uint32_t d)
{
return b^c^d;
}
std::uint32_t f3(std::uint32_t b,std::uint32_t c,std::uint32_t d)
{
return (b&c)|(b&d)|(c&d);
}
void printRound(std::size_t i,std::uint32_t a,std::uint32_t b,std::uint32_t c,std::uint32_t d,std::uint32_t e,
std::uint32_t f,std::uint32_t k,std::uint32_t w)
{
std::cout< if(i<80)
{
std::cout<<" | "< }
std::cout<<'\n';
}
#define PRINT_ROUND(i) printRound((i),a[i],b[i],c[i],d[i],e[i],f[i],k[i],w[i])
int main()
{
std::uint32_t a[82],b[82],c[82],d[82],e[82];
a[0]=0x67452301;
b[0]=0xefcdab89;
c[0]=0x98badcfe;
d[0]=0x10325476;
e[0]=0xc3d2e1f0;
std::uint32_t w[82]=
{
0x80000000,0x00000000,0x00000000,0x00000000,
0x00000000,0x00000000,0x00000000,0x00000000,
0x00000000,0x00000000,0x00000000,0x00000000,
0x00000000,0x00000000,0x00000000,0x00000000
};
for(std::size_t i=16;i<80;++i)
{
w[i]=rotateLeft(w[i-3]^w[i-8]^w[i-14]^w[i-16],1);
}
std::uint32_t f[82],k[82];
std::cout<<"i a[i] b[i] c[i] d[i] e[i] f[i] k[i] w[i] \n";
std::cout<<"---------------------------------------------------------------------------------\n";
for(std::size_t i=0;i<20;++i)
{
f[i]=f1(b[i],c[i],d[i]);
k[i]=0x5a827999;
PRINT_ROUND(i);
a[i+1]=rotateLeft(a[i],5)+f[i]+e[i]+k[i]+w[i];
b[i+1]=a[i];
c[i+1]=rotateLeft(b[i],30);
d[i+1]=c[i];
e[i+1]=d[i];
}
for(std::size_t i=20;i<40;++i)
{
f[i]=f2(b[i],c[i],d[i]);
k[i]=0x6ed9eba1;
PRINT_ROUND(i);
a[i+1]=rotateLeft(a[i],5)+f[i]+e[i]+k[i]+w[i];
b[i+1]=a[i];
c[i+1]=rotateLeft(b[i],30);
d[i+1]=c[i];
e[i+1]=d[i];
}
for(std::size_t i=40;i<60;++i)
{
f[i]=f3(b[i],c[i],d[i]);
k[i]=0x8f1bbcdc;
PRINT_ROUND(i);
a[i+1]=rotateLeft(a[i],5)+f[i]+e[i]+k[i]+w[i];
b[i+1]=a[i];
c[i+1]=rotateLeft(b[i],30);
d[i+1]=c[i];
e[i+1]=d[i];
}
for(std::size_t i=60;i<80;++i)
{
f[i]=f2(b[i],c[i],d[i]);
k[i]=0xca62c1d6;
PRINT_ROUND(i);
a[i+1]=rotateLeft(a[i],5)+f[i]+e[i]+k[i]+w[i];
b[i+1]=a[i];
c[i+1]=rotateLeft(b[i],30);
d[i+1]=c[i];
e[i+1]=d[i];
}
PRINT_ROUND(80);
a[81]=a[80]+a[0];
b[81]=b[80]+b[0];
c[81]=c[80]+c[0];
d[81]=d[80]+d[0];
e[81]=e[80]+e[0];
PRINT_ROUND(81);
}
And then, you can see exactly, step-by-step, how SHA-1 of the empty message is changed into its hash:
i a[i] b[i] c[i] d[i] e[i] f[i] k[i] w[i]
---------------------------------------------------------------------------------
0 67452301 efcdab89 98badcfe 10325476 c3d2e1f0 | 98badcfe 5a827999 80000000
1 1fb498b3 67452301 7bf36ae2 98badcfe 10325476 | fbfbfefe 5a827999 00000000
2 5d43e370 1fb498b3 59d148c0 7bf36ae2 98badcfe | 79d36ac0 5a827999 00000000
3 158d2f62 5d43e370 c7ed262c 59d148c0 7bf36ae2 | 45d12aa0 5a827999 00000000
4 cdecfb5d 158d2f62 1750f8dc c7ed262c 59d148c0 | d760284c 5a827999 00000000
5 4953565e cdecfb5d 85634bd8 1750f8dc c7ed262c | 97704bd8 5a827999 00000000
6 e44ab766 4953565e 737b3ed7 85634bd8 1750f8dc | c5731fd6 5a827999 00000000
7 c09d7f27 e44ab766 9254d597 737b3ed7 85634bd8 | 93719d97 5a827999 00000000
8 87074800 c09d7f27 b912add9 9254d597 737b3ed7 | 9250ad91 5a827999 00000000
9 41376611 87074800 f0275fc9 b912add9 9254d597 | b817edd9 5a827999 00000000
10 cbdbff31 41376611 21c1d200 f0275fc9 b912add9 | b1015bc8 5a827999 00000000
11 40166973 cbdbff31 504dd984 21c1d200 f0275fc9 | 6049d900 5a827999 00000000
12 adc0e0ca 40166973 72f6ffcc 504dd984 21c1d200 | 505ff9c4 5a827999 00000000
13 84c05eb2 adc0e0ca d0059a5c 72f6ffcc 504dd984 | d2369f4c 5a827999 00000000
14 1512c8b9 84c05eb2 ab703832 d0059a5c 72f6ffcc | d045987e 5a827999 00000000
15 40182905 1512c8b9 a13017ac ab703832 d0059a5c | ab7030aa 5a827999 00000000
16 d8fd6547 40182905 4544b22e a13017ac ab703832 | e12036ac 5a827999 00000001
17 06bf9173 d8fd6547 50060a41 4544b22e a13017ac | 55049269 5a827999 00000000
18 28a9520e 06bf9173 f63f5951 50060a41 4544b22e | 563f1b51 5a827999 00000000
19 0b3088dd 28a9520e c1afe45c f63f5951 50060a41 | d6bf495d 5a827999 00000002
20 e758e8da 0b3088dd 8a2a5483 c1afe45c f63f5951 | 40b53802 6ed9eba1 00000000
21 90eb9850 e758e8da 42cc2237 8a2a5483 c1afe45c | 2fbe9e6e 6ed9eba1 00000000
22 7dbb787d 90eb9850 b9d63a36 42cc2237 8a2a5483 | 6bf18051 6ed9eba1 00000004
23 1c64d028 7dbb787d 243ae614 b9d63a36 42cc2237 | e057a45f 6ed9eba1 00000000
24 1e97b73a 1c64d028 5f6ede1f 243ae614 b9d63a36 | 6730e823 6ed9eba1 00000002
25 62d7f53f 1e97b73a 0719340a 5f6ede1f 243ae614 | 46e05d2f 6ed9eba1 00000008
26 34f3d6d8 62d7f53f 87a5edce 0719340a 5f6ede1f | e26b2cfb 6ed9eba1 00000000
27 4f2ed1c1 34f3d6d8 d8b5fd4f 87a5edce 0719340a | 6be3c659 6ed9eba1 00000000
28 c7b11e2d 4f2ed1c1 0d3cf5b6 d8b5fd4f 87a5edce | 9aa7d938 6ed9eba1 00000010
29 874b786f c7b11e2d 53cbb470 0d3cf5b6 d8b5fd4f | 99465feb 6ed9eba1 00000000
30 ca4556cb 874b786f 71ec478b 53cbb470 0d3cf5b6 | a56c8b94 6ed9eba1 0000000a
31 6a2e466e ca4556cb e1d2de1b 71ec478b 53cbb470 | 5a7bcf5b 6ed9eba1 00000020
32 62ea3d59 6a2e466e f29155b2 e1d2de1b 71ec478b | 796dcdc7 6ed9eba1 00000006
33 b77bac25 62ea3d59 9a8b919b f29155b2 e1d2de1b | 0af0f970 6ed9eba1 00000000
34 4b1347e2 b77bac25 58ba8f56 9a8b919b f29155b2 | 754ab2e8 6ed9eba1 00000040
35 391ef0c4 4b1347e2 6ddeeb09 58ba8f56 9a8b919b | 7e7723bd 6ed9eba1 00000008
36 abbab988 391ef0c4 92c4d1f8 6ddeeb09 58ba8f56 | c604ca35 6ed9eba1 00000028
37 04f07669 abbab988 0e47bc31 92c4d1f8 6ddeeb09 | 3739d441 6ed9eba1 00000080
38 b201788b 04f07669 2aeeae62 0e47bc31 92c4d1f8 | 2059643a 6ed9eba1 00000008
39 62273351 b201788b 413c1d9a 2aeeae62 0e47bc31 | d9d3cb73 6ed9eba1 00000000
40 9bdbdd71 62273351 ec805e22 413c1d9a 2aeeae62 | 60241f12 8f1bbcdc 00000108
41 95aa398b 9bdbdd71 5889ccd4 ec805e22 413c1d9a | d889dc70 8f1bbcdc 00000000
42 5e28e858 95aa398b 66f6f75c 5889ccd4 ec805e22 | 54aafddc 8f1bbcdc 000000a0
43 95642485 5e28e858 e56a8e62 66f6f75c 5889ccd4 | 666aee58 8f1bbcdc 00000200
44 fa950aba 95642485 178a3a16 e56a8e62 66f6f75c | 956a2e06 8f1bbcdc 00000064
45 de1e3a01 fa950aba 65590921 178a3a16 e56a8e62 | 77990a32 8f1bbcdc 00000000
46 afe695ab de1e3a01 bea542ae 65590921 178a3a16 | fe1d0a21 8f1bbcdc 00000408
47 a195ba90 afe695ab 77878e80 bea542ae 65590921 | bfa786aa 8f1bbcdc 00000088
48 e6d39f43 a195ba90 ebf9a56a 77878e80 bea542ae | e395ae80 8f1bbcdc 0000029c
49 0bca9922 e6d39f43 28656ea4 ebf9a56a 77878e80 | eaf1af62 8f1bbcdc 00000800
50 6ae826ff 0bca9922 f9b4e7d0 28656ea4 ebf9a56a | 29e4efa0 8f1bbcdc 00000080
51 01ff3253 6ae826ff 82f2a648 f9b4e7d0 28656ea4 | eaf0a6d8 8f1bbcdc 00000028
52 e2581ce0 01ff3253 daba09bf 82f2a648 f9b4e7d0 | 82fa225b 8f1bbcdc 00001088
53 56ce73ab e2581ce0 c07fcc94 daba09bf 82f2a648 | c27a0cb4 8f1bbcdc 00000000
54 ae56e542 56ce73ab 38960738 c07fcc94 daba09bf | 50de47b8 8f1bbcdc 00000a40
55 8590c0e8 ae56e542 d5b39cea 38960738 c07fcc94 | bc96856a 8f1bbcdc 00002000
56 be4a4bea 8590c0e8 ab95b950 d5b39cea 38960738 | 859198e8 8f1bbcdc 00000668
57 168ce0bb be4a4bea 2164303a ab95b950 d5b39cea | ab44397a 8f1bbcdc 00000080
58 e1afab22 168ce0bb af9292fa 2164303a ab95b950 | 2784b0ba 8f1bbcdc 00004088
59 982bcbca e1afab22 c5a3382e af9292fa 2164303a | e5a3ba2a 8f1bbcdc 00000880
60 9b9d2913 982bcbca b86beac8 c5a3382e af9292fa | e5e3192c ca62c1d6 000028c8
61 d37db937 9b9d2913 a60af2f2 b86beac8 c5a3382e | 85fc3129 ca62c1d6 00008000
62 85b9d227 d37db937 e6e74a44 a60af2f2 b86beac8 | 93900181 ca62c1d6 000008a8
63 cd98fbb7 85b9d227 f4df6e4d e6e74a44 a60af2f2 | 9781f62e ca62c1d6 00000080
64 bb0f226f cd98fbb7 e16e7489 f4df6e4d e6e74a44 | d829e173 ca62c1d6 000108e8
65 eb59446c bb0f226f f3663eed e16e7489 f4df6e4d | a907680b ca62c1d6 00000000
66 d37225cb eb59446c eec3c89b f3663eed e16e7489 | f6fcb21a ca62c1d6 0000a000
67 111341f3 d37225cb 3ad6511b eec3c89b f3663eed | 0767bc4b ca62c1d6 00020080
68 e79afbf0 111341f3 f4dc8972 3ad6511b eec3c89b | df19999a ca62c1d6 00006400
69 8ba00627 e79afbf0 c444d07c f4dc8972 3ad6511b | d702a2fe ca62c1d6 00000000
70 503c7ae0 8ba00627 39e6befc c444d07c f4dc8972 | 760268a7 ca62c1d6 00040800
71 3cd517f9 503c7ae0 e2e80189 39e6befc c444d07c | 8b32c595 ca62c1d6 00008800
72 b47ddf0e 3cd517f9 140f1eb8 e2e80189 39e6befc | ca3208c8 ca62c1d6 00029c10
73 5e3a0780 b47ddf0e 4f3545fe 140f1eb8 e2e80189 | ef478448 ca62c1d6 00080000
74 63db37b2 5e3a0780 ad1f77c3 4f3545fe 140f1eb8 | bc1035bd ca62c1d6 00008080
75 15e98d17 63db37b2 178e81e0 ad1f77c3 4f3545fe | d94ac191 ca62c1d6 00002820
76 b0149467 15e98d17 98f6cdec 178e81e0 ad1f77c3 | 9a91c11b ca62c1d6 001088c0
77 14b7106a b0149467 c57a6345 98f6cdec 178e81e0 | ed983ace ca62c1d6 00000000
78 666b8bc6 14b7106a ec052519 c57a6345 98f6cdec | 3dc85636 ca62c1d6 000a40c0
79 6e9d9f84 666b8bc6 852dc41a ec052519 c57a6345 | 0f436ac5 ca62c1d6 00200080
80 72f480ed 6e9d9f84 999ae2f1 852dc41a ec052519
81 da39a3ee 5e6b4b0d 3255bfef 95601890 afd80709
Then, you can compare it with other tools, and check that SHA-1("")=da39a3ee5e6b4b0d3255bfef95601890afd80709, that means all computations are correct.
Edit:
I tried different online services and all of their output differed from bitcoin's. That's why I asked.
I guess you used text mode, while Bitcoin uses binary mode. For example, if you have "12345678" as some message to be hashed, then your message probably was in this form:
31323334 35363738 80000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000040
But what you should use, was that form:
12345678 80000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000000
00000000 00000000 00000000 00000020
And then, you can compare those hashes:
SHA-1("12345678")=7c222fb2927d828af22f592134e8932480637c0d
SHA-1(0x12345678)=9bce73d0c8b9eca4f24154f3bd3b8aa473b1c3a9Another thing is endianness. For example, maybe you used 0x78563412, while you should use 0x12345678.
To move things forward, I can give you the Genesis Block hash as an example of how things should be computed:
SHA-256(0100000000000000000000000000000000000000000000000000000000000000000000003ba3edfd7a7b12b27ac72c3e67768f617fc81bc3888a51323a9fb8aa4b1e5e4a29ab5f49ffff001d1dac2b7c)=af42031e805ff493a07341e2f74ff58149d22ab9ba19f61343e2c86c71c5d66d
SHA-256(af42031e805ff493a07341e2f74ff58149d22ab9ba19f61343e2c86c71c5d66d)=6fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000000000
And then, you can notice that the result of SHA-256 is reversed. The reason is that little-endian is used in many places, for example in hashes. And that's why you have to change endianness many times, and process hashes byte-by-byte, and put them in reversed order. The same is true for many other fields, for example you can see 0x01000000 as version, that means 0x00000001, because of endianness.
Edit: Also, I made some introduction to hash functions in another topic, it can be useful if you want to try some basic attacks:
https://bitcointalksearch.org/topic/why-hash-functions-are-safe-5402178
