KEYRING-IPINT(2) KEYRING-IPINT(2)
NAME
keyring: IPint - `infinite' precision integer utility
functions
SYNOPSIS
include "keyring.m"
keyring:= load Keyring Keyring->PATH;
IPint: adt
{
iptob64: fn(i: self ref IPint): string;
b64toip: fn(str: string) : ref IPint;
iptobytes: fn(i: self ref IPint): array of byte;
bytestoip: fn(buf: array of byte): ref IPint;
iptobebytes: fn(i: self ref IPint): array of byte;
bebytestoip: fn(buf: array of byte): ref IPint;
inttoip: fn(i: int): ref IPint;
iptoint: fn(i: self ref IPint): int;
iptostr: fn(i: self ref IPint, base: int): string;
strtoip: fn(str: string, base: int): ref IPint;
random: fn(minbits, maxbits: int): ref IPint;
copy: fn(i: self ref IPint): ref IPint;
bits: fn(i: self ref IPint): int;
expmod: fn(base: self ref IPint, exp, mod: ref IPint):ref IPint;
add: fn(i1: self ref IPint, i2: ref IPint): ref IPint;
sub: fn(i1: self ref IPint, i2: ref IPint): ref IPint;
neg: fn(i: self ref IPint): ref IPint;
mul: fn(i1: self ref IPint, i2: ref IPint): ref IPint;
div: fn(i1: self ref IPint, i2: ref IPint): (ref IPint, ref IPint);
eq: fn(i1: self ref IPint, i2: ref IPint): int;
cmp: fn(i1: self ref IPint, i2: ref IPint): int;
shl: fn(i: self ref IPint, n: int): ref IPint;
shr: fn(i: self ref IPint, n: int): ref IPint;
and: fn(i1: self ref IPint, i2: ref IPint): ref IPint;
ori: fn(i1: self ref IPint, i2: ref IPint): ref IPint;
not: fn(i: self ref IPint): ref IPint;
xor: fn(i1: self ref IPint, i2: ref IPint): ref IPint;
};
DESCRIPTION
IPint provides the following arbitrary-length integer manip-
ulation functions required for cryptographic support in
Limbo:
i.iptob64()
Returns a string that represents a large integer textu-
ally in base 64 for convenient transmission over a net-
work connection.
b64toip(str)
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KEYRING-IPINT(2) KEYRING-IPINT(2)
Returns the IPint represented by the base-64 encoded
str.
i.iptobytes()
Returns an array of bytes representing a large integer.
The representation includes both positive and negative
numbers.
bytestoip(buf)
The inverse operation of iptobytes.
i.iptobebytes()
Returns an array of bytes in big-endian format repre-
senting the magnitude of a large integer; used for
instance to pass a value to ssl(3). Only non-negative
numbers are represented.
bebytestoip(buf)
The inverse operation of iptobebytes.
inttoip(i)
Creates a new large integer from integer i.
i.iptoint()
Converts a large integer i to an int; returns 0 on
error.
i.iptostr(base)
Converts a large integer to a string in base base;
returns nil on error. Only the bases 10, 16, 32, and
64 are supported. Anything else defaults to 16.
strtoip(str,base)
Converts a string str representing a number in in base
base to a large integer; returns nil on error. Only
the bases 10, 16, 32, and 64 are supported.
random(minbits,maxbits)
Returns a large random number with length from minbits
to maxbits. The largest number allowed in the current
implementation is 2^8192-1 . The seed for the genera-
tor is obtained by duelling clocks.
i.copy()
Returns a reference to the same value as i.
i.bits()
Returns the number of bits of precision of i.
base.expmod(exp , mod)
Returns (base**exp) mod mod.
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KEYRING-IPINT(2) KEYRING-IPINT(2)
i1.add(i2)
Returns (i1+i2).
i1.sub(i2)
Returns (i1-i2).
i1.mul(i2)
Returns i1*i2.
i1.div(i2)
Returns (i1/i2, i1modi2).
i1.eq(i2)
Returns 1 if i1 and i2 are equal; 0 otherwise.
i1.cmp(i2)
Compares two large integers, returning 1 if i1 is
larger, -1 if i2 is larger, and 0 if they are equal.
i.shl(n)
Returns i<<n
i.shr(n)
Returns i>>n
i1.and(i2)
Returns i&n, bitwise AND
i1.ori(i2)
Returns i|n, bitwise inclusive-OR (it is ori because
plain or is a Limbo keyword)
i.not()
Returns ~i, bitwise ones-complement
i1.xor(i2)
Returns i^n, bitwise exclusive-OR
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