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) Page 1 Plan 9 (printed 11/23/24) 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. Page 2 Plan 9 (printed 11/23/24) 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 Page 3 Plan 9 (printed 11/23/24)