SSHSecure/moduli/struct.go

/*
   SSHSecure - a program to harden OpenSSH from defaults
   Copyright (C) 2020  Brent Saner

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

package moduli

import (
	"math/big"
	"time"
)

// Moduli contains all data needed for generated /etc/ssh/moduli of Entry entries.
type Moduli struct {
	Header string
	Groups []Entry
}

// Entry is a struct reflecting the format of a single /etc/ssh/moduli entry. See moduli(5) for details.
type Entry struct {
	Time time.Time // YYYYMMDDHHSS
	/*
		// man 5 moduli:
			Decimal number specifying the internal structure of the prime modulus.  Supported types are:
			0     Unknown, not tested.
			2     "Safe" prime; (p-1)/2 is also prime.
			4     Sophie Germain; 2p+1 is also prime.
			Moduli candidates initially produced by ssh-keygen(1) are Sophie Germain primes (type 4).
			Further primality testing with ssh-keygen(1) produces safe prime moduli (type 2) that are ready for use in sshd(8).
			Other types are not used by OpenSSH.
	*/
	Type uint8
	/*
		// man 5 moduli:
			Decimal number indicating the type of primality tests that the number has been
			subjected to represented as a bitmask of the following values:
			0x00  Not tested.
			0x01  Composite number – not prime.
			0x02  Sieve of Eratosthenes.
			0x04  Probabilistic Miller-Rabin primality tests.
			The ssh-keygen(1) moduli candidate generation uses the Sieve of Eratosthenes (flag 0x02).
			Subsequent ssh-keygen(1) primality tests are Miller-Rabin tests (flag 0x04).
	*/
	Tests uint8
	/*
		// man 5 moduli:
			Decimal number indicating the number of primality trials that have been performed on the modulus.
	*/
	Trials uint8
	/*
		// man 5 moduli:
			Decimal number indicating the size of the prime in bits.
	*/
	Size uint16
	/*
		// man 5 moduli:
			The recommended generator for use with this modulus (hexadecimal).
	*/
	Generator uint8
	/*
		// man 5 moduli:
			The modulus itself in hexadecimal.
	*/
	Modulus big.Int
}