a

include/mp.h

@@ -0,0 +1,134 @@
+#define _MPINT 1
+
+// the code assumes mpdigit to be at least an int
+// mpdigit must be an atomic type.  mpdigit is defined
+// in the architecture specific u.h
+
+typedef struct mpint mpint;
+
+struct mpint
+{
+	int	sign;	// +1 or -1
+	int	size;	// allocated digits
+	int	top;	// significant digits
+	mpdigit	*p;
+	char	flags;
+};
+
+enum
+{
+	MPstatic=	0x01,
+	Dbytes=		sizeof(mpdigit),	// bytes per digit
+	Dbits=		Dbytes*8		// bits per digit
+};
+
+// allocation
+void	mpsetminbits(int n);	// newly created mpint's get at least n bits
+mpint*	mpnew(int n);		// create a new mpint with at least n bits
+void	mpfree(mpint *b);
+void	mpbits(mpint *b, int n);	// ensure that b has at least n bits
+void	mpnorm(mpint *b);		// dump leading zeros
+mpint*	mpcopy(mpint *b);
+void	mpassign(mpint *old, mpint *new);
+
+// random bits
+mpint*	mprand(int bits, void (*gen)(uchar*, int), mpint *b);
+
+// conversion
+mpint*	strtomp(char*, char**, int, mpint*);	// ascii
+int	mpfmt(Fmt*);
+char*	mptoa(mpint*, int, char*, int);
+mpint*	letomp(uchar*, uint, mpint*);	// byte array, little-endian
+int	mptole(mpint*, uchar*, uint, uchar**);
+mpint*	betomp(uchar*, uint, mpint*);	// byte array, little-endian
+int	mptobe(mpint*, uchar*, uint, uchar**);
+uint	mptoui(mpint*);			// unsigned int
+mpint*	uitomp(uint, mpint*);
+int	mptoi(mpint*);			// int
+mpint*	itomp(int, mpint*);
+uvlong	mptouv(mpint*);			// unsigned vlong
+mpint*	uvtomp(uvlong, mpint*);
+vlong	mptov(mpint*);			// vlong
+mpint*	vtomp(vlong, mpint*);
+
+// divide 2 digits by one
+void	mpdigdiv(mpdigit *dividend, mpdigit divisor, mpdigit *quotient);
+
+// in the following, the result mpint may be
+// the same as one of the inputs.
+void	mpadd(mpint *b1, mpint *b2, mpint *sum);	// sum = b1+b2
+void	mpsub(mpint *b1, mpint *b2, mpint *diff);	// diff = b1-b2
+void	mpleft(mpint *b, int shift, mpint *res);	// res = b<<shift
+void	mpright(mpint *b, int shift, mpint *res);	// res = b>>shift
+void	mpmul(mpint *b1, mpint *b2, mpint *prod);	// prod = b1*b2
+void	mpexp(mpint *b, mpint *e, mpint *m, mpint *res);	// res = b**e mod m
+void	mpmod(mpint *b, mpint *m, mpint *remainder);	// remainder = b mod m
+
+// quotient = dividend/divisor, remainder = dividend % divisor
+void	mpdiv(mpint *dividend, mpint *divisor,  mpint *quotient, mpint *remainder);
+
+// return neg, 0, pos as b1-b2 is neg, 0, pos
+int	mpcmp(mpint *b1, mpint *b2);
+
+// extended gcd return d, x, and y, s.t. d = gcd(a,b) and ax+by = d
+void	mpextendedgcd(mpint *a, mpint *b, mpint *d, mpint *x, mpint *y);
+
+// res = b**-1 mod m
+void	mpinvert(mpint *b, mpint *m, mpint *res);
+
+// bit counting
+int	mpsignif(mpint*);	// number of sigificant bits in mantissa
+int	mplowbits0(mpint*);	// k, where n = 2**k * q for odd q
+
+// well known constants
+extern mpint	*mpzero, *mpone, *mptwo;
+
+// sum[0:alen] = a[0:alen-1] + b[0:blen-1]
+// prereq: alen >= blen, sum has room for alen+1 digits
+void	mpvecadd(mpdigit *a, int alen, mpdigit *b, int blen, mpdigit *sum);
+
+// diff[0:alen-1] = a[0:alen-1] - b[0:blen-1]
+// prereq: alen >= blen, diff has room for alen digits
+void	mpvecsub(mpdigit *a, int alen, mpdigit *b, int blen, mpdigit *diff);
+
+// p[0:n] += m * b[0:n-1]
+// prereq: p has room for n+1 digits
+void	mpvecdigmuladd(mpdigit *b, int n, mpdigit m, mpdigit *p);
+
+// p[0:n] -= m * b[0:n-1]
+// prereq: p has room for n+1 digits
+int	mpvecdigmulsub(mpdigit *b, int n, mpdigit m, mpdigit *p);
+
+// p[0:alen*blen-1] = a[0:alen-1] * b[0:blen-1]
+// prereq: alen >= blen, p has room for m*n digits
+void	mpvecmul(mpdigit *a, int alen, mpdigit *b, int blen, mpdigit *p);
+
+// sign of a - b or zero if the same
+int	mpveccmp(mpdigit *a, int alen, mpdigit *b, int blen);
+
+// divide the 2 digit dividend by the one digit divisor and stick in quotient
+// we assume that the result is one digit - overflow is all 1's
+void	mpdigdiv(mpdigit *dividend, mpdigit divisor, mpdigit *quotient);
+
+// playing with magnitudes
+int	mpmagcmp(mpint *b1, mpint *b2);
+void	mpmagadd(mpint *b1, mpint *b2, mpint *sum);	// sum = b1+b2
+void	mpmagsub(mpint *b1, mpint *b2, mpint *sum);	// sum = b1+b2
+
+// chinese remainder theorem
+typedef struct CRTpre	CRTpre;		// precomputed values for converting
+					//  twixt residues and mpint
+typedef struct CRTres	CRTres;		// residue form of an mpint
+
+struct CRTres
+{
+	int	n;		// number of residues
+	mpint	*r[1];		// residues
+};
+
+CRTpre*	crtpre(int, mpint**);			// precompute conversion values
+CRTres*	crtin(CRTpre*, mpint*);			// convert mpint to residues
+void	crtout(CRTpre*, CRTres*, mpint*);	// convert residues to mpint
+void	crtprefree(CRTpre*);
+void	crtresfree(CRTres*);
+