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Verifying SHA-256 seed values

Wikipedia lists pseudocode for http://en.wikipedia.org/wiki/SHA-2#PseudocodeSHA-256, including seed values. Better check if they’re right.

#!/usr/bin/perl
use strict;
print <<HERE;
Initialize hash values:
(first 32 bits of the fractional parts of the square roots of the first 8 primes 2..19):
HERE
my ($p, $r) = 0;
while ($r < 8) {
  next if (!prime(++$p));
  printf("h%d := 0x%sn", $r++, bits($p, 1/2));
}
print <<HERE;

Initialize array of round constants:
(first 32 bits of the fractional parts of the cube roots of the first 64 primes 2..311):
k[0..63] :=
HERE

my ($p, $r) = 0;
while ($r < 64) {
  next if (!prime(++$p));
  print "   " if ($r++ % 8 == 0);
  printf("0x%s", bits($p, 1/3));
  print "," if ($r < 64);
  print $r % 8 == 0 ? "n" : " ";
}
sub prime { # http://diswww.mit.edu/bloom-picayune.mit.edu/perl/10138
  return ((1 x shift) !~ /^1?$|^(11+?)1+$/);
}
sub bits {
  my ($v, $m) = @_;
  return unpack("H*", pack("N", ($v ** $m – int($v ** $m)) * 2**32));
}

Results:

macbook:/Users/chrisl/ 142$ perl test.pl
Initialize hash values:
(first 32 bits of the fractional parts of the square roots of the first 8 primes 2..19):
h0 := 0x6a09e667
h1 := 0xbb67ae85
h2 := 0x3c6ef372
h3 := 0xa54ff53a
h4 := 0x510e527f
h5 := 0x9b05688c
h6 := 0x1f83d9ab
h7 := 0x5be0cd19

Initialize array of round constants:
(first 32 bits of the fractional parts of the cube roots of the first 64 primes 2..311):
k[0..63] :=
   0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
   0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
   0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
   0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
   0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
   0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
   0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
   0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2

Better safe than sorry!

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