diff options
| author | siddharth <s@ricketyspace.net> | 2021-10-10 11:18:25 -0400 | 
|---|---|---|
| committer | siddharth <s@ricketyspace.net> | 2021-10-10 11:18:25 -0400 | 
| commit | 244d10ac25d1adc0f10e089f8d457269b109897d (patch) | |
| tree | e4a94f6967a973f8cd2e1edc258a7958be05e185 | |
| parent | f9c878cbad59a98490e832703f19abf49bd6738f (diff) | |
lib: move sha arithmetic functions to hash.go
| -rw-r--r-- | lib/hash.go | 19 | ||||
| -rw-r--r-- | lib/sha1.go | 35 | 
2 files changed, 27 insertions, 27 deletions
| diff --git a/lib/hash.go b/lib/hash.go index f0f4625..363d3d6 100644 --- a/lib/hash.go +++ b/lib/hash.go @@ -28,6 +28,25 @@ func shaMessageBlocks(pm []byte) [][]uint32 {  	return mbs  } +// (a + b + ...) mod 2^32 +func shaAdd(n ...uint32) uint32 { +	sum := uint64(0) +	for _, v := range n { +		sum += uint64(v) +	} +	return uint32(sum & 0xFFFFFFFF) +} + +// Circular Right Shift +func shaRotr(x uint32, n uint) uint32 { +	return (x >> n) | (x << (32 - n)) +} + +// Circular Left Shift +func shaRotl(x uint32, n uint) uint32 { +	return (x << n) | (x >> (32 - n)) +} +  // Returns Merkle–Damgård padding in bytes for length of mesage `l`  // bytes.  func MDPadding(l int) []byte { diff --git a/lib/sha1.go b/lib/sha1.go index 5010bfb..e4ab369 100644 --- a/lib/sha1.go +++ b/lib/sha1.go @@ -21,25 +21,6 @@ var sha1IHashValues []uint32 = []uint32{  	0xc3d2e1f0,  } -// (a + b + ...) mod 2^32 -func sha1Add(n ...uint32) uint32 { -	sum := uint64(0) -	for _, v := range n { -		sum += uint64(v) -	} -	return uint32(sum & 0xFFFFFFFF) -} - -// Circular Right Shift -func sha1Rotr(x uint32, n uint) uint32 { -	return (x >> n) | (x << (32 - n)) -} - -// Circular Left Shift -func sha1Rotl(x uint32, n uint) uint32 { -	return (x << n) | (x >> (32 - n)) -} -  // SHA-1 - Function f_t(x, y, z)  func sha1FT(t int, x, y, z uint32) uint32 {  	switch { @@ -83,7 +64,7 @@ func sha1MessageSchedule(mb []uint32) []uint32 {  		if t <= 15 {  			w = append(w, mb[t])  		} else { -			w = append(w, sha1Rotl(w[t-3]^w[t-8]^w[t-14]^w[t-16], 1)) +			w = append(w, shaRotl(w[t-3]^w[t-8]^w[t-14]^w[t-16], 1))  		}  	}  	return w @@ -142,21 +123,21 @@ func (s *Sha1) Hash() []byte {  		e := h[4]  		for t := 0; t <= 79; t++ { -			tmp := sha1Add(sha1Rotl(a, 5), sha1FT(t, b, c, d), +			tmp := shaAdd(shaRotl(a, 5), sha1FT(t, b, c, d),  				e, sha1KT(t), w[t])  			e = d  			d = c -			c = sha1Rotl(b, 30) +			c = shaRotl(b, 30)  			b = a  			a = tmp  		}  		// Compute intermediate hash values. -		h[0] = sha1Add(a, h[0]) -		h[1] = sha1Add(b, h[1]) -		h[2] = sha1Add(c, h[2]) -		h[3] = sha1Add(d, h[3]) -		h[4] = sha1Add(e, h[4]) +		h[0] = shaAdd(a, h[0]) +		h[1] = shaAdd(b, h[1]) +		h[2] = shaAdd(c, h[2]) +		h[3] = shaAdd(d, h[3]) +		h[4] = shaAdd(e, h[4])  	}  	// Slurp sha1 digest from hash values. | 
