implement Sha1;
include "sha1.m";


sha1(p: array of byte): array of byte
{
	state := array[5] of int;
	state[0] = 16r67452301;
	state[1] = int 16rEFCDAB89;
	state[2] = int 16r98BADCFE;
	state[3] = 16r10325476;
	state[4] = int 16rC3D2E1F0;

	l := len p;
	p = sha1block(p, state);

	q: array of byte;
	if(len p < 56)
		q = array[64] of { * => byte 0 };
	else
		q = array[128] of { * => byte 0 };
	q[0:] = p[0:];
	q[len p] = byte 16r80;
	end := q[len q-8:];
	end[4] = byte (l>>24);
	end[5] = byte (l>>16);
	end[6] = byte (l>>8);
	end[7] = byte l;

	sha1block(q, state);

	d := array[20] of byte;
	j := 0;
	for(i:=0; i<5; i++){
		d[j++] = byte (state[i]>>24);
		d[j++] = byte (state[i]>>16);
		d[j++] = byte (state[i]>>8);
		d[j++] = byte (state[i]);
	}
	return d;
}

sha1block(p: array of byte, s: array of int): array of byte
{
	w := array[80] of int;

	while(len p >= 64){
		a := s[0];
		b := s[1];
		c := s[2];
		d := s[3];
		e := s[4];

		wp := w;
		for(i:=0; i<3; i++){
			wp[0] = ((int p[0])<<24) | ((int p[1])<<16) | ((int p[2])<<8) | (int p[3]);
			e += ((a<<5) | (a>>27)) + wp[0];
			e += 16r5a827999 + (((c^d)&b)^d);
			b = (b<<30)|(b>>2);

			wp[1] = ((int p[4])<<24) | ((int p[5])<<16) | ((int p[6])<<8) | (int p[7]);
			d += ((e<<5) | (e>>27)) + wp[1];
			d += 16r5a827999 + (((b^c)&a)^c);
			a = (a<<30)|(a>>2);

			wp[2] = ((int p[8])<<24) | ((int p[9])<<16) | ((int p[10])<<8) | (int p[11]);
			c += ((d<<5) | (d>>27)) + wp[2];
			c += 16r5a827999 + (((a^b)&e)^b);
			e = (e<<30)|(e>>2);

			wp[3] = ((int p[12])<<24) | ((int p[13])<<16) | ((int p[14])<<8) | (int p[15]);
			b += ((c<<5) | (c>>27)) + wp[3];
			b += 16r5a827999 + (((e^a)&d)^a);
			d = (d<<30)|(d>>2);

			wp[4] = ((int p[16])<<24) | ((int p[17])<<16) | ((int p[18])<<8) | (int p[19]);
			a += ((b<<5) | (b>>27)) + wp[4];
			a += 16r5a827999 + (((d^e)&c)^e);
			c = (c<<30)|(c>>2);
			
			p = p[20:];
			wp = wp[5:];
		}

		wp = w;
		wp[15+0] = ((int p[0])<<24) | ((int p[1])<<16) | ((int p[2])<<8) | (int p[3]);
		e += ((a<<5) | (a>>27)) + wp[15+0];
		e += 16r5a827999 + (((c^d)&b)^d);
		b = (b<<30)|(b>>2);

		x := wp[15+-2] ^ wp[15+-7] ^ wp[15+-13] ^ wp[15+-15];
		wp[15+1] = (x<<1) | (x>>31);
		d += ((e<<5) | (e>>27)) + wp[15+1];
		d += 16r5a827999 + (((b^c)&a)^c);
		a = (a<<30)|(a>>2);

		x = wp[15+-1] ^ wp[15+-6] ^ wp[15+-12] ^ wp[15+-14];
		wp[15+2] = (x<<1) | (x>>31);
		c += ((d<<5) | (d>>27)) + wp[15+2];
		c += 16r5a827999 + (((a^b)&e)^b);
		e = (e<<30)|(e>>2);

		x = wp[15+0] ^ wp[15+-5] ^ wp[15+-11] ^ wp[15+-13];
		wp[15+3] = (x<<1) | (x>>31);
		b += ((c<<5) | (c>>27)) + wp[15+3];
		b += 16r5a827999 + (((e^a)&d)^a);
		d = (d<<30)|(d>>2);

		x = wp[15+1] ^ wp[15+-4] ^ wp[15+-10] ^ wp[15+-12];
		wp[15+4] = (x<<1) | (x>>31);
		a += ((b<<5) | (b>>27)) + wp[15+4];
		a += 16r5a827999 + (((d^e)&c)^e);
		c = (c<<30)|(c>>2);

		p = p[4:];

		wp = w;
		for(i=0; i<4; i++){
			x = wp[20+-3] ^ wp[20+-8] ^ wp[20+-14] ^ wp[20+-16];
			wp[20+0] = (x<<1) | (x>>31);
			e += ((a<<5) | (a>>27)) + wp[20+0];
			e += 16r6ed9eba1 + (b^c^d);
			b = (b<<30)|(b>>2);

			x = wp[20+-2] ^ wp[20+-7] ^ wp[20+-13] ^ wp[20+-15];
			wp[20+1] = (x<<1) | (x>>31);
			d += ((e<<5) | (e>>27)) + wp[20+1];
			d += 16r6ed9eba1 + (a^b^c);
			a = (a<<30)|(a>>2);

			x = wp[20+-1] ^ wp[20+-6] ^ wp[20+-12] ^ wp[20+-14];
			wp[20+2] = (x<<1) | (x>>31);
			c += ((d<<5) | (d>>27)) + wp[20+2];
			c += 16r6ed9eba1 + (e^a^b);
			e = (e<<30)|(e>>2);

			x = wp[20+0] ^ wp[20+-5] ^ wp[20+-11] ^ wp[20+-13];
			wp[20+3] = (x<<1) | (x>>31);
			b += ((c<<5) | (c>>27)) + wp[20+3];
			b += 16r6ed9eba1 + (d^e^a);
			d = (d<<30)|(d>>2);

			x = wp[20+1] ^ wp[20+-4] ^ wp[20+-10] ^ wp[20+-12];
			wp[20+4] = (x<<1) | (x>>31);
			a += ((b<<5) | (b>>27)) + wp[20+4];
			a += 16r6ed9eba1 + (c^d^e);
			c = (c<<30)|(c>>2);
			wp = wp[5:];
		}

		for(i=0; i<4; i++){
			x = wp[20+-3] ^ wp[20+-8] ^ wp[20+-14] ^ wp[20+-16];
			wp[20+0] = (x<<1) | (x>>31);
			e += ((a<<5) | (a>>27)) + wp[20+0];
			e += int 16r8f1bbcdc + ((b&c)|((b|c)&d));
			b = (b<<30)|(b>>2);

			x = wp[20+-2] ^ wp[20+-7] ^ wp[20+-13] ^ wp[20+-15];
			wp[20+1] = (x<<1) | (x>>31);
			d += ((e<<5) | (e>>27)) + wp[20+1];
			d += int 16r8f1bbcdc + ((a&b)|((a|b)&c));
			a = (a<<30)|(a>>2);

			x = wp[20+-1] ^ wp[20+-6] ^ wp[20+-12] ^ wp[20+-14];
			wp[20+2] = (x<<1) | (x>>31);
			c += ((d<<5) | (d>>27)) + wp[20+2];
			c += int 16r8f1bbcdc + ((e&a)|((e|a)&b));
			e = (e<<30)|(e>>2);

			x = wp[20+0] ^ wp[20+-5] ^ wp[20+-11] ^ wp[20+-13];
			wp[20+3] = (x<<1) | (x>>31);
			b += ((c<<5) | (c>>27)) + wp[20+3];
			b += int 16r8f1bbcdc + ((d&e)|((d|e)&a));
			d = (d<<30)|(d>>2);

			x = wp[20+1] ^ wp[20+-4] ^ wp[20+-10] ^ wp[20+-12];
			wp[20+4] = (x<<1) | (x>>31);
			a += ((b<<5) | (b>>27)) + wp[20+4];
			a += int 16r8f1bbcdc + ((c&d)|((c|d)&e));
			c = (c<<30)|(c>>2);
			wp = wp[5:];
		}

		for(i=0; i<4; i++){
			x = wp[20+-3] ^ wp[20+-8] ^ wp[20+-14] ^ wp[20+-16];
			wp[20+0] = (x<<1) | (x>>31);
			e += ((a<<5) | (a>>27)) + wp[20+0];
			e += int 16rca62c1d6 + (b^c^d);
			b = (b<<30)|(b>>2);

			x = wp[20+-2] ^ wp[20+-7] ^ wp[20+-13] ^ wp[20+-15];
			wp[20+1] = (x<<1) | (x>>31);
			d += ((e<<5) | (e>>27)) + wp[20+1];
			d += int 16rca62c1d6 + (a^b^c);
			a = (a<<30)|(a>>2);

			x = wp[20+-1] ^ wp[20+-6] ^ wp[20+-12] ^ wp[20+-14];
			wp[20+2] = (x<<1) | (x>>31);
			c += ((d<<5) | (d>>27)) + wp[20+2];
			c += int 16rca62c1d6 + (e^a^b);
			e = (e<<30)|(e>>2);

			x = wp[20+0] ^ wp[20+-5] ^ wp[20+-11] ^ wp[20+-13];
			wp[20+3] = (x<<1) | (x>>31);
			b += ((c<<5) | (c>>27)) + wp[20+3];
			b += int 16rca62c1d6 + (d^e^a);
			d = (d<<30)|(d>>2);

			x = wp[20+1] ^ wp[20+-4] ^ wp[20+-10] ^ wp[20+-12];
			wp[20+4] = (x<<1) | (x>>31);
			a += ((b<<5) | (b>>27)) + wp[20+4];
			a += int 16rca62c1d6 + (c^d^e);
			c = (c<<30)|(c>>2);

			wp = wp[5:];
		}

		s[0] += a;
		s[1] += b;
		s[2] += c;
		s[3] += d;
		s[4] += e;
	}
	return p;
}