added unix path protocol

codec.go

@@ -8,6 +8,7 @@ import (
 	"net"
 	"strconv"
 	"strings"
+	"errors"
 
 	mh "github.com/jbenet/go-multihash"
 )
@@ -43,6 +44,12 @@ func stringToBytes(s string) ([]byte, error) {
 			return nil, fmt.Errorf("protocol requires address, none given: %s", p.Name)
 		}
 
+		if p.Path {
+			// it's a path protocol (terminal).
+			// consume the rest of the address as the next component.
+			sp = []string{"/" + strings.Join(sp, "/")}
+		}
+
 		a, err := addressStringToBytes(p, sp[0])
 		if err != nil {
 			return nil, fmt.Errorf("failed to parse %s: %s %s", p.Name, sp[0], err)
@@ -134,12 +141,17 @@ func sizeForAddr(p Protocol, b []byte) (int, error) {
 		return (p.Size / 8), nil
 	case p.Size == 0:
 		return 0, nil
+	case p.Path:
+		size, n, err := ReadVarintCode(b)
+		if err != nil {
+			return 0, err
+		}
+		return size + n, nil
 	default:
 		size, n, err := ReadVarintCode(b)
 		if err != nil {
 			return 0, err
 		}
-
 		return size + n, nil
 	}
 }
@@ -243,6 +255,12 @@ func addressStringToBytes(p Protocol, s string) ([]byte, error) {
 		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)
@@ -269,7 +287,7 @@ func addressBytesToString(p Protocol, b []byte) (string, error) {
 
 		b = b[n:]
 		if len(b) != size {
-			return "", fmt.Errorf("inconsistent lengths")
+			return "", errors.New("inconsistent lengths")
 		}
 		m, err := mh.Cast(b)
 		if err != nil {
@@ -282,7 +300,25 @@ func addressBytesToString(p Protocol, b []byte) (string, error) {
 		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 "", fmt.Errorf("unknown protocol")
+		return "", errors.New("unknown protocol")
 	}
 }

multiaddr.go

@@ -144,7 +144,7 @@ func (m *multiaddr) ValueForProtocol(code int) (string, error) {
 			if p.Size == 0 {
 				return "", nil
 			}
-			return strings.Split(sub.String(), "/")[2], nil
+			return strings.SplitN(sub.String(), "/", 3)[2], nil
 		}
 	}
 

multiaddr_test.go

@@ -43,6 +43,8 @@ func TestConstructFails(t *testing.T) {
 		"/ip4/127.0.0.1/tcp",
 		"/ip4/127.0.0.1/ipfs",
 		"/ip4/127.0.0.1/ipfs/tcp",
+		"/unix",
+		"/ip4/1.2.3.4/tcp/80/unix",
 	}
 
 	for _, a := range cases {
@@ -81,6 +83,10 @@ func TestConstructSucceeds(t *testing.T) {
 		"/ip4/127.0.0.1/tcp/1234/",
 		"/ip4/127.0.0.1/ipfs/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC",
 		"/ip4/127.0.0.1/ipfs/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC/tcp/1234",
+		"/unix/a/b/c/d/e",
+		"/unix/stdio",
+		"/ip4/1.2.3.4/tcp/80/unix/a/b/c/d/e/f",
+		"/ip4/127.0.0.1/ipfs/QmcgpsyWgH8Y8ajJz1Cu72KnS5uo2Aa2LpzU7kinSupNKC/tcp/1234/unix/stdio",
 	}
 
 	for _, a := range cases {
@@ -353,6 +359,10 @@ func TestGetValue(t *testing.T) {
 	assertValueForProto(t, a, P_IP4, "0.0.0.0")
 	assertValueForProto(t, a, P_UDP, "12345")
 	assertValueForProto(t, a, P_UTP, "")
+
+	a = newMultiaddr(t, "/ip4/0.0.0.0/unix/a/b/c/d") // ending in a path one.
+	assertValueForProto(t, a, P_IP4, "0.0.0.0")
+	assertValueForProto(t, a, P_UNIX, "a/b/c/d")
 }
 
 func TestFuzzBytes(t *testing.T) {

protocols.csv

@@ -1,4 +1,5 @@
 code	size	name
+
 4	32	ip4
 6	16	tcp
 17	16	udp
@@ -7,6 +8,7 @@ code	size	name
 132	16	sctp
 301	0	utp
 302	0	udt
+400 V unix
 421	V	ipfs
 480	0	http
 443	0	https

protocols.go

@@ -12,6 +12,7 @@ type Protocol struct {
 	Size  int // a size of -1 indicates a length-prefixed variable size
 	Name  string
 	VCode []byte
+	Path  bool // indicates a path protocol (eg unix, http)
 }
 
 // replicating table here to:
@@ -27,6 +28,7 @@ const (
 	P_SCTP  = 132
 	P_UTP   = 301
 	P_UDT   = 302
+	P_UNIX  = 400
 	P_IPFS  = 421
 	P_HTTP  = 480
 	P_HTTPS = 443
@@ -40,19 +42,20 @@ const (
 
 // Protocols is the list of multiaddr protocols supported by this module.
 var Protocols = []Protocol{
-	Protocol{P_IP4, 32, "ip4", CodeToVarint(P_IP4)},
-	Protocol{P_TCP, 16, "tcp", CodeToVarint(P_TCP)},
-	Protocol{P_UDP, 16, "udp", CodeToVarint(P_UDP)},
-	Protocol{P_DCCP, 16, "dccp", CodeToVarint(P_DCCP)},
-	Protocol{P_IP6, 128, "ip6", CodeToVarint(P_IP6)},
+	Protocol{P_IP4, 32, "ip4", CodeToVarint(P_IP4), false},
+	Protocol{P_TCP, 16, "tcp", CodeToVarint(P_TCP), false},
+	Protocol{P_UDP, 16, "udp", CodeToVarint(P_UDP), false},
+	Protocol{P_DCCP, 16, "dccp", CodeToVarint(P_DCCP), false},
+	Protocol{P_IP6, 128, "ip6", CodeToVarint(P_IP6), false},
 	// these require varint:
-	Protocol{P_SCTP, 16, "sctp", CodeToVarint(P_SCTP)},
-	Protocol{P_ONION, 96, "onion", CodeToVarint(P_ONION)},
-	Protocol{P_UTP, 0, "utp", CodeToVarint(P_UTP)},
-	Protocol{P_UDT, 0, "udt", CodeToVarint(P_UDT)},
-	Protocol{P_HTTP, 0, "http", CodeToVarint(P_HTTP)},
-	Protocol{P_HTTPS, 0, "https", CodeToVarint(P_HTTPS)},
-	Protocol{P_IPFS, LengthPrefixedVarSize, "ipfs", CodeToVarint(P_IPFS)},
+	Protocol{P_SCTP, 16, "sctp", CodeToVarint(P_SCTP), false},
+	Protocol{P_ONION, 96, "onion", CodeToVarint(P_ONION), false},
+	Protocol{P_UTP, 0, "utp", CodeToVarint(P_UTP), false},
+	Protocol{P_UDT, 0, "udt", CodeToVarint(P_UDT), false},
+	Protocol{P_HTTP, 0, "http", CodeToVarint(P_HTTP), false},
+	Protocol{P_HTTPS, 0, "https", CodeToVarint(P_HTTPS), false},
+	Protocol{P_IPFS, LengthPrefixedVarSize, "ipfs", CodeToVarint(P_IPFS), false},
+	Protocol{P_UNIX, LengthPrefixedVarSize, "unix", CodeToVarint(P_UNIX), true},
 }
 
 func AddProtocol(p Protocol) error {