add Transocoder functionality

Allowing multiaddr extensions to have data with
This commit is contained in:
Jakub Sztandera 2016-10-14 11:48:19 -04:00
parent 0de18dfd80
commit 1919305418
No known key found for this signature in database
GPG Key ID: 9A9AF56F8B3879BA
3 changed files with 202 additions and 168 deletions

158
codec.go
View File

@ -2,15 +2,8 @@ package multiaddr
import ( import (
"bytes" "bytes"
"encoding/base32"
"encoding/binary"
"errors"
"fmt" "fmt"
"net"
"strconv"
"strings" "strings"
mh "github.com/multiformats/go-multihash"
) )
func stringToBytes(s string) ([]byte, error) { func stringToBytes(s string) ([]byte, error) {
@ -50,7 +43,10 @@ func stringToBytes(s string) ([]byte, error) {
sp = []string{"/" + strings.Join(sp, "/")} sp = []string{"/" + strings.Join(sp, "/")}
} }
a, err := addressStringToBytes(p, sp[0]) if p.Transcoder == nil {
return nil, fmt.Errorf("no transcoder for %s protocol", p.Name)
}
a, err := p.Transcoder.StringToBytes(sp[0])
if err != nil { if err != nil {
return nil, fmt.Errorf("failed to parse %s: %s %s", p.Name, sp[0], err) return nil, fmt.Errorf("failed to parse %s: %s %s", p.Name, sp[0], err)
} }
@ -122,7 +118,10 @@ func bytesToString(b []byte) (ret string, err error) {
return "", fmt.Errorf("invalid value for size") return "", fmt.Errorf("invalid value for size")
} }
a, err := addressBytesToString(p, b[:size]) if p.Transcoder == nil {
return "", fmt.Errorf("no transcoder for %s protocol", p.Name)
}
a, err := p.Transcoder.BytesToString(b[:size])
if err != nil { if err != nil {
return "", err return "", err
} }
@ -181,144 +180,3 @@ func bytesSplit(b []byte) ([][]byte, error) {
return ret, nil return ret, nil
} }
func addressStringToBytes(p Protocol, s string) ([]byte, error) {
switch p.Code {
case P_IP4: // ipv4
i := net.ParseIP(s).To4()
if i == nil {
return nil, fmt.Errorf("failed to parse ip4 addr: %s", s)
}
return i, nil
case P_IP6: // ipv6
i := net.ParseIP(s).To16()
if i == nil {
return nil, fmt.Errorf("failed to parse ip6 addr: %s", s)
}
return i, nil
// tcp udp dccp sctp
case P_TCP, P_UDP, P_DCCP, P_SCTP:
i, err := strconv.Atoi(s)
if err != nil {
return nil, fmt.Errorf("failed to parse %s addr: %s", p.Name, err)
}
if i >= 65536 {
return nil, fmt.Errorf("failed to parse %s addr: %s", p.Name, "greater than 65536")
}
b := make([]byte, 2)
binary.BigEndian.PutUint16(b, uint16(i))
return b, nil
case P_ONION:
addr := strings.Split(s, ":")
if len(addr) != 2 {
return nil, fmt.Errorf("failed to parse %s addr: %s does not contain a port number.", p.Name, s)
}
// onion address without the ".onion" substring
if len(addr[0]) != 16 {
return nil, fmt.Errorf("failed to parse %s addr: %s not a Tor onion address.", p.Name, s)
}
onionHostBytes, err := base32.StdEncoding.DecodeString(strings.ToUpper(addr[0]))
if err != nil {
return nil, fmt.Errorf("failed to decode base32 %s addr: %s %s", p.Name, s, err)
}
// onion port number
i, err := strconv.Atoi(addr[1])
if err != nil {
return nil, fmt.Errorf("failed to parse %s addr: %s", p.Name, err)
}
if i >= 65536 {
return nil, fmt.Errorf("failed to parse %s addr: %s", p.Name, "port greater than 65536")
}
if i < 1 {
return nil, fmt.Errorf("failed to parse %s addr: %s", p.Name, "port less than 1")
}
onionPortBytes := make([]byte, 2)
binary.BigEndian.PutUint16(onionPortBytes, uint16(i))
bytes := []byte{}
bytes = append(bytes, onionHostBytes...)
bytes = append(bytes, onionPortBytes...)
return bytes, nil
case P_IPFS: // ipfs
// the address is a varint prefixed multihash string representation
m, err := mh.FromB58String(s)
if err != nil {
return nil, fmt.Errorf("failed to parse ipfs addr: %s %s", s, err)
}
size := CodeToVarint(len(m))
b := append(size, m...)
return b, nil
case P_UNIX:
// the address is the whole remaining string, prefixed by a varint len
size := CodeToVarint(len(s))
b := append(size, []byte(s)...)
return b, nil
}
return []byte{}, fmt.Errorf("failed to parse %s addr: unknown", p.Name)
}
func addressBytesToString(p Protocol, b []byte) (string, error) {
switch p.Code {
// ipv4,6
case P_IP4, P_IP6:
return net.IP(b).String(), nil
// tcp udp dccp sctp
case P_TCP, P_UDP, P_DCCP, P_SCTP:
i := binary.BigEndian.Uint16(b)
return strconv.Itoa(int(i)), nil
case P_IPFS: // ipfs
// the address is a varint-prefixed multihash string representation
size, n, err := ReadVarintCode(b)
if err != nil {
return "", err
}
b = b[n:]
if len(b) != size {
return "", errors.New("inconsistent lengths")
}
m, err := mh.Cast(b)
if err != nil {
return "", err
}
return m.B58String(), nil
case P_ONION:
addr := strings.ToLower(base32.StdEncoding.EncodeToString(b[0:10]))
port := binary.BigEndian.Uint16(b[10:12])
return addr + ":" + strconv.Itoa(int(port)), nil
case P_UNIX:
// the address is a varint len prefixed string
size, n, err := ReadVarintCode(b)
if err != nil {
return "", err
}
b = b[n:]
if len(b) != size {
return "", errors.New("inconsistent lengths")
}
if size == 0 {
return "", errors.New("invalid length")
}
s := string(b)
s = s[1:] // remove starting slash
return s, nil
default:
return "", errors.New("unknown protocol")
}
}

View File

@ -8,11 +8,12 @@ import (
// Protocol is a Multiaddr protocol description structure. // Protocol is a Multiaddr protocol description structure.
type Protocol struct { type Protocol struct {
Code int Code int
Size int // a size of -1 indicates a length-prefixed variable size Size int // a size of -1 indicates a length-prefixed variable size
Name string Name string
VCode []byte VCode []byte
Path bool // indicates a path protocol (eg unix, http) Path bool // indicates a path protocol (eg unix, http)
Transcoder Transcoder
} }
// replicating table here to: // replicating table here to:
@ -42,20 +43,20 @@ const (
// Protocols is the list of multiaddr protocols supported by this module. // Protocols is the list of multiaddr protocols supported by this module.
var Protocols = []Protocol{ var Protocols = []Protocol{
Protocol{P_IP4, 32, "ip4", CodeToVarint(P_IP4), false}, Protocol{P_IP4, 32, "ip4", CodeToVarint(P_IP4), false, TranscoderIP4},
Protocol{P_TCP, 16, "tcp", CodeToVarint(P_TCP), false}, Protocol{P_TCP, 16, "tcp", CodeToVarint(P_TCP), false, TranscoderPort},
Protocol{P_UDP, 16, "udp", CodeToVarint(P_UDP), false}, Protocol{P_UDP, 16, "udp", CodeToVarint(P_UDP), false, TranscoderPort},
Protocol{P_DCCP, 16, "dccp", CodeToVarint(P_DCCP), false}, Protocol{P_DCCP, 16, "dccp", CodeToVarint(P_DCCP), false, TranscoderPort},
Protocol{P_IP6, 128, "ip6", CodeToVarint(P_IP6), false}, Protocol{P_IP6, 128, "ip6", CodeToVarint(P_IP6), false, TranscoderIP6},
// these require varint: // these require varint:
Protocol{P_SCTP, 16, "sctp", CodeToVarint(P_SCTP), false}, Protocol{P_SCTP, 16, "sctp", CodeToVarint(P_SCTP), false, TranscoderPort},
Protocol{P_ONION, 96, "onion", CodeToVarint(P_ONION), false}, Protocol{P_ONION, 96, "onion", CodeToVarint(P_ONION), false, TranscoderOnion},
Protocol{P_UTP, 0, "utp", CodeToVarint(P_UTP), false}, Protocol{P_UTP, 0, "utp", CodeToVarint(P_UTP), false, nil},
Protocol{P_UDT, 0, "udt", CodeToVarint(P_UDT), false}, Protocol{P_UDT, 0, "udt", CodeToVarint(P_UDT), false, nil},
Protocol{P_HTTP, 0, "http", CodeToVarint(P_HTTP), false}, Protocol{P_HTTP, 0, "http", CodeToVarint(P_HTTP), false, nil},
Protocol{P_HTTPS, 0, "https", CodeToVarint(P_HTTPS), false}, Protocol{P_HTTPS, 0, "https", CodeToVarint(P_HTTPS), false, nil},
Protocol{P_IPFS, LengthPrefixedVarSize, "ipfs", CodeToVarint(P_IPFS), false}, Protocol{P_IPFS, LengthPrefixedVarSize, "ipfs", CodeToVarint(P_IPFS), false, TranscoderIPFS},
Protocol{P_UNIX, LengthPrefixedVarSize, "unix", CodeToVarint(P_UNIX), true}, Protocol{P_UNIX, LengthPrefixedVarSize, "unix", CodeToVarint(P_UNIX), true, TranscoderUnix},
} }
func AddProtocol(p Protocol) error { func AddProtocol(p Protocol) error {

175
transcoders.go Normal file
View File

@ -0,0 +1,175 @@
package multiaddr
import (
"encoding/base32"
"encoding/binary"
"errors"
"fmt"
"net"
"strconv"
"strings"
mh "github.com/multiformats/go-multihash"
)
type Transcoder interface {
StringToBytes(string) ([]byte, error)
BytesToString([]byte) (string, error)
}
type twrp struct {
strtobyte func(string) ([]byte, error)
bytetostr func([]byte) (string, error)
}
func (t twrp) StringToBytes(s string) ([]byte, error) {
return t.strtobyte(s)
}
func (t twrp) BytesToString(b []byte) (string, error) {
return t.bytetostr(b)
}
var TranscoderIP4 = (Transcoder)(twrp{ip4StB, ipBtS})
var TranscoderIP6 = (Transcoder)(twrp{ip6StB, ipBtS})
func ip4StB(s string) ([]byte, error) {
i := net.ParseIP(s).To4()
if i == nil {
return nil, fmt.Errorf("failed to parse ip4 addr: %s", s)
}
return i, nil
}
func ip6StB(s string) ([]byte, error) {
i := net.ParseIP(s).To16()
if i == nil {
return nil, fmt.Errorf("failed to parse ip4 addr: %s", s)
}
return i, nil
}
func ipBtS(b []byte) (string, error) {
return net.IP(b).String(), nil
}
var TranscoderPort = (Transcoder)(twrp{portStB, portBtS})
func portStB(s string) ([]byte, error) {
i, err := strconv.Atoi(s)
if err != nil {
return nil, fmt.Errorf("failed to parse port addr: %s", err)
}
if i >= 65536 {
return nil, fmt.Errorf("failed to parse port addr: %s", "greater than 65536")
}
b := make([]byte, 2)
binary.BigEndian.PutUint16(b, uint16(i))
return b, nil
}
func portBtS(b []byte) (string, error) {
i := binary.BigEndian.Uint16(b)
return strconv.Itoa(int(i)), nil
}
var TranscoderOnion = (Transcoder)(twrp{onionStB, onionBtS})
func onionStB(s string) ([]byte, error) {
addr := strings.Split(s, ":")
if len(addr) != 2 {
return nil, fmt.Errorf("failed to parse onion addr: %s does not contain a port number.", s)
}
// onion address without the ".onion" substring
if len(addr[0]) != 16 {
return nil, fmt.Errorf("failed to parse onion addr: %s not a Tor onion address.", s)
}
onionHostBytes, err := base32.StdEncoding.DecodeString(strings.ToUpper(addr[0]))
if err != nil {
return nil, fmt.Errorf("failed to decode base32 onion addr: %s %s", s, err)
}
// onion port number
i, err := strconv.Atoi(addr[1])
if err != nil {
return nil, fmt.Errorf("failed to parse onion addr: %s", err)
}
if i >= 65536 {
return nil, fmt.Errorf("failed to parse onion addr: %s", "port greater than 65536")
}
if i < 1 {
return nil, fmt.Errorf("failed to parse onion addr: %s", "port less than 1")
}
onionPortBytes := make([]byte, 2)
binary.BigEndian.PutUint16(onionPortBytes, uint16(i))
bytes := []byte{}
bytes = append(bytes, onionHostBytes...)
bytes = append(bytes, onionPortBytes...)
return bytes, nil
}
func onionBtS(b []byte) (string, error) {
addr := strings.ToLower(base32.StdEncoding.EncodeToString(b[0:10]))
port := binary.BigEndian.Uint16(b[10:12])
return addr + ":" + strconv.Itoa(int(port)), nil
}
var TranscoderIPFS = (Transcoder)(twrp{ipfsStB, ipfsBtS})
func ipfsStB(s string) ([]byte, error) {
// the address is a varint prefixed multihash string representation
m, err := mh.FromB58String(s)
if err != nil {
return nil, fmt.Errorf("failed to parse ipfs addr: %s %s", s, err)
}
size := CodeToVarint(len(m))
b := append(size, m...)
return b, nil
}
func ipfsBtS(b []byte) (string, error) {
// the address is a varint-prefixed multihash string representation
size, n, err := ReadVarintCode(b)
if err != nil {
return "", err
}
b = b[n:]
if len(b) != size {
return "", errors.New("inconsistent lengths")
}
m, err := mh.Cast(b)
if err != nil {
return "", err
}
return m.B58String(), nil
}
var TranscoderUnix = (Transcoder)(twrp{unixStB, unixBtS})
func unixStB(s string) ([]byte, error) {
// the address is the whole remaining string, prefixed by a varint len
size := CodeToVarint(len(s))
b := append(size, []byte(s)...)
return b, nil
}
func unixBtS(b []byte) (string, error) {
// the address is a varint len prefixed string
size, n, err := ReadVarintCode(b)
if err != nil {
return "", err
}
b = b[n:]
if len(b) != size {
return "", errors.New("inconsistent lengths")
}
if size == 0 {
return "", errors.New("invalid length")
}
s := string(b)
s = s[1:] // remove starting slash
return s, nil
}