conterm/include/mp.h

135 lines
4.4 KiB
C

#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*);