RosettaCodeData/Task/RIPEMD-160/Ruby/ripemd-160-3.rb

119 lines
4.0 KiB
Ruby

require 'stringio'
module RMD160
# functions and constants
MASK = (1 << 32) - 1
F = [
proc {|x, y, z| x ^ y ^ z},
proc {|x, y, z| (x & y) | (x.^(MASK) & z)},
proc {|x, y, z| (x | y.^(MASK)) ^ z},
proc {|x, y, z| (x & z) | (y & z.^(MASK))},
proc {|x, y, z| x ^ (y | z.^(MASK))},
].freeze
K = [0x00000000, 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xa953fd4e]
KK = [0x50a28be6, 0x5c4dd124, 0x6d703ef3, 0x7a6d76e9, 0x00000000]
R = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
7, 4, 13, 1, 10, 6, 15, 3, 12, 0, 9, 5, 2, 14, 11, 8,
3, 10, 14, 4, 9, 15, 8, 1, 2, 7, 0, 6, 13, 11, 5, 12,
1, 9, 11, 10, 0, 8, 12, 4, 13, 3, 7, 15, 14, 5, 6, 2,
4, 0, 5, 9, 7, 12, 2, 10, 14, 1, 3, 8, 11, 6, 15, 13]
RR = [5, 14, 7, 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12,
6, 11, 3, 7, 0, 13, 5, 10, 14, 15, 8, 12, 4, 9, 1, 2,
15, 5, 1, 3, 7, 14, 6, 9, 11, 8, 12, 2, 10, 0, 4, 13,
8, 6, 4, 1, 3, 11, 15, 0, 5, 12, 2, 13, 9, 7, 10, 14,
12, 15, 10, 4, 1, 5, 8, 7, 6, 2, 13, 14, 0, 3, 9, 11]
S = [11, 14, 15, 12, 5, 8, 7, 9, 11, 13, 14, 15, 6, 7, 9, 8,
7, 6, 8, 13, 11, 9, 7, 15, 7, 12, 15, 9, 11, 7, 13, 12,
11, 13, 6, 7, 14, 9, 13, 15, 14, 8, 13, 6, 5, 12, 7, 5,
11, 12, 14, 15, 14, 15, 9, 8, 9, 14, 5, 6, 8, 6, 5, 12,
9, 15, 5, 11, 6, 8, 13, 12, 5, 12, 13, 14, 11, 8, 5, 6]
SS = [8, 9, 9, 11, 13, 15, 15, 5, 7, 7, 8, 11, 14, 14, 12, 6,
9, 13, 15, 7, 12, 8, 9, 11, 7, 7, 12, 7, 6, 15, 13, 11,
9, 7, 15, 11, 8, 6, 6, 14, 12, 13, 5, 14, 13, 13, 7, 5,
15, 5, 8, 11, 14, 14, 6, 14, 6, 9, 12, 9, 12, 5, 15, 8,
8, 5, 12, 9, 12, 5, 14, 6, 8, 13, 6, 5, 15, 13, 11, 11]
module_function
def rol(value, shift)
(value << shift).&(MASK) | (value.&(MASK) >> (32 - shift))
end
# Calculates RIPEMD-160 message digest of _string_. Returns binary
# digest. For hexadecimal digest, use
# +*RMD160.rmd160(string).unpack('H*')+.
def rmd160(string)
# initial hash
h0 = 0x67452301
h1 = 0xefcdab89
h2 = 0x98badcfe
h3 = 0x10325476
h4 = 0xc3d2e1f0
io = StringIO.new(string)
block = ""
term = false # appended "\x80" in second-last block?
last = false # last block?
until last
# Read next block of 16 words (64 bytes, 512 bits).
io.read(64, block) or (
# Work around a bug in Rubinius 1.2.4. At eof,
# MRI and JRuby already replace block with "".
block.replace("")
)
# Unpack block into 32-bit words "V".
case len = block.length
when 64
# Unpack 16 words.
x = block.unpack("V16")
when 56..63
# Second-last block: append padding, unpack 16 words.
block.concat("\x80"); term = true
block.concat("\0" * (63 - len))
x = block.unpack("V16")
when 0..55
# Last block: append padding, unpack 14 words.
block.concat(term ? "\0" : "\x80")
block.concat("\0" * (55 - len))
x = block.unpack("V14")
# Append bit length, 2 words.
bit_len = string.length << 3
x.push(bit_len & MASK, bit_len >> 32)
last = true
else
fail "impossible"
end
# Process this block.
a, b, c, d, e = h0, h1, h2, h3, h4
aa, bb, cc, dd, ee = h0, h1, h2, h3, h4
j = 0
5.times {|ro|
f, ff = F[ro], F[4 - ro]
k, kk = K[ro], KK[ro]
16.times {
a, e, d, c, b = e, d, rol(c, 10), b,
rol(a + f[b, c, d] + x[R[j]] + k, S[j]) + e
aa, ee, dd, cc, bb = ee, dd, rol(cc, 10), bb,
rol(aa + ff[bb, cc, dd] + x[RR[j]] + kk, SS[j]) + ee
j += 1
}
}
h0, h1, h2, h3, h4 =
(h1 + c + dd) & MASK, (h2 + d + ee) & MASK,
(h3 + e + aa) & MASK, (h4 + a + bb) & MASK,
(h0 + b + cc) & MASK
end # until last
[h0, h1, h2, h3, h4].pack("V5")
end
end
if __FILE__ == $0
# Print an example RIPEMD-160 digest.
str = 'Rosetta Code'
printf "%s:\n %s\n", str, *RMD160.rmd160(str).unpack('H*')
end