1. moved address to core

src/address/address.go

@@ -1,150 +0,0 @@
-// Package address contains the types used by mesh to represent IPv6 addresses or prefixes, as well as functions for working with these types.
-// Of particular importance are the functions used to derive addresses or subnets from a NodeID, or to get the NodeID and bitmask of the bits visible from an address, which is needed for DHT searches.
-package address
-
-import (
-	"crypto/ed25519"
-)
-
-// Address represents an IPv6 address in the mesh address range.
-type Address [16]byte
-
-// Subnet represents an IPv6 /64 subnet in the mesh subnet range.
-type Subnet [8]byte
-
-// GetPrefix returns the address prefix used by mesh.
-// The current implementation requires this to be a multiple of 8 bits + 7 bits.
-// The 8th bit of the last byte is used to signal nodes (0) or /64 prefixes (1).
-// Nodes that configure this differently will be unable to communicate with each other using IP packets, though routing and the DHT machinery *should* still work.
-func GetPrefix() [1]byte {
-	return [...]byte{0xfc}
-}
-
-// IsValid returns true if an address falls within the range used by nodes in the network.
-func (a *Address) IsValid() bool {
-	prefix := GetPrefix()
-	for idx := range prefix {
-		if (*a)[idx] != prefix[idx] {
-			return false
-		}
-	}
-	return true
-}
-
-// IsValid returns true if a prefix falls within the range usable by the network.
-func (s *Subnet) IsValid() bool {
-	prefix := GetPrefix()
-	l := len(prefix)
-	for idx := range prefix[:l-1] {
-		if (*s)[idx] != prefix[idx] {
-			return false
-		}
-	}
-	return (*s)[l-1] == prefix[l-1]|0x01
-}
-
-// AddrForKey takes an ed25519.PublicKey as an argument and returns an *Address.
-// This function returns nil if the key length is not ed25519.PublicKeySize.
-// This address begins with the contents of GetPrefix(), with the last bit set to 0 to indicate an address.
-// The following 8 bits are set to the number of leading 1 bits in the bitwise inverse of the public key.
-// The bitwise inverse of the key, excluding the leading 1 bits and the first leading 0 bit, is truncated to the appropriate length and makes up the remainder of the address.
-func AddrForKey(publicKey ed25519.PublicKey) *Address {
-	// 128 bit address
-	// Begins with prefix
-	// Next bit is a 0
-	// Next 7 bits, interpreted as a uint, are # of leading 1s in the NodeID
-	// Leading 1s and first leading 0 of the NodeID are truncated off
-	// The rest is appended to the IPv6 address (truncated to 128 bits total)
-	if len(publicKey) != ed25519.PublicKeySize {
-		return nil
-	}
-	var buf [ed25519.PublicKeySize]byte
-	copy(buf[:], publicKey)
-	for idx := range buf {
-		buf[idx] = ^buf[idx]
-	}
-	var addr Address
-	var temp = make([]byte, 0, 32)
-	done := false
-	ones := byte(0)
-	bits := byte(0)
-	nBits := 0
-	for idx := 0; idx < 8*len(buf); idx++ {
-		bit := (buf[idx/8] & (0x80 >> byte(idx%8))) >> byte(7-(idx%8))
-		if !done && bit != 0 {
-			ones++
-			continue
-		}
-		if !done && bit == 0 {
-			done = true
-			continue // FIXME? this assumes that ones <= 127, probably only worth changing by using a variable length uint64, but that would require changes to the addressing scheme, and I'm not sure ones > 127 is realistic
-		}
-		bits = (bits << 1) | bit
-		nBits++
-		if nBits == 8 {
-			nBits = 0
-			temp = append(temp, bits)
-		}
-	}
-	prefix := GetPrefix()
-	copy(addr[:], prefix[:])
-	addr[len(prefix)] = ones
-	copy(addr[len(prefix)+1:], temp)
-	return &addr
-}
-
-// SubnetForKey takes an ed25519.PublicKey as an argument and returns a *Subnet.
-// This function returns nil if the key length is not ed25519.PublicKeySize.
-// The subnet begins with the address prefix, with the last bit set to 1 to indicate a prefix.
-// The following 8 bits are set to the number of leading 1 bits in the bitwise inverse of the key.
-// The bitwise inverse of the key, excluding the leading 1 bits and the first leading 0 bit, is truncated to the appropriate length and makes up the remainder of the subnet.
-func SubnetForKey(publicKey ed25519.PublicKey) *Subnet {
-	// Exactly as the address version, with two exceptions:
-	//  1) The first bit after the fixed prefix is a 1 instead of a 0
-	//  2) It's truncated to a subnet prefix length instead of 128 bits
-	addr := AddrForKey(publicKey)
-	if addr == nil {
-		return nil
-	}
-	var snet Subnet
-	copy(snet[:], addr[:])
-	prefix := GetPrefix() // nolint:staticcheck
-	snet[len(prefix)-1] |= 0x01
-	return &snet
-}
-
-// GetKet returns the partial ed25519.PublicKey for the Address.
-// This is used for key lookup.
-func (a *Address) GetKey() ed25519.PublicKey {
-	var key [ed25519.PublicKeySize]byte
-	prefix := GetPrefix() // nolint:staticcheck
-	ones := int(a[len(prefix)])
-	for idx := 0; idx < ones; idx++ {
-		key[idx/8] |= 0x80 >> byte(idx%8)
-	}
-	keyOffset := ones + 1
-	addrOffset := 8*len(prefix) + 8
-	for idx := addrOffset; idx < 8*len(a); idx++ {
-		bits := a[idx/8] & (0x80 >> byte(idx%8))
-		bits <<= byte(idx % 8)
-		keyIdx := keyOffset + (idx - addrOffset)
-		bits >>= byte(keyIdx % 8)
-		idx := keyIdx / 8
-		if idx >= len(key) {
-			break
-		}
-		key[idx] |= bits
-	}
-	for idx := range key {
-		key[idx] = ^key[idx]
-	}
-	return ed25519.PublicKey(key[:])
-}
-
-// GetKet returns the partial ed25519.PublicKey for the Subnet.
-// This is used for key lookup.
-func (s *Subnet) GetKey() ed25519.PublicKey {
-	var addr Address
-	copy(addr[:], s[:])
-	return addr.GetKey()
-}