Change vendored weave mesh to use hash keys by default

This means we don't have to use build tags when building, so our code
is more go-gettable.  Also bazel doesn't support build tags yet, so we
need to do something like this for a bazel build (otherwise gossip DNS
is broken)

Gopkg.lock

@@ -1788,6 +1788,6 @@
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "c083db22a03ca0fe3ccc11361c91a444e674aa1ec6fb0aba6447b4b4982c0355"
+  inputs-digest = "0201881428ebf85b06c6a6868cbc8f0885841e2395a64631bb9406681da3c197"
   solver-name = "gps-cdcl"
   solver-version = 1

Makefile

@@ -469,10 +469,15 @@ dep-prereqs:
 .PHONY: dep-ensure
 dep-ensure: dep-prereqs
 	dep ensure -v
+	# Switch weavemesh to use peer_name_hash - bazel rule-go doesn't support build tags yet
+	rm vendor/github.com/weaveworks/mesh/peer_name_mac.go
+	sed -i -e 's/peer_name_hash/!peer_name_mac/g' vendor/github.com/weaveworks/mesh/peer_name_hash.go
+	# Remove all bazel build files that were vendored and regenerate (we assume they are go-gettable)
 	find vendor/ -name "BUILD" -delete
 	find vendor/ -name "BUILD.bazel" -delete
 	bazel run //:gazelle -- -proto disable
 
+
 .PHONY: gofmt
 gofmt:
 	gofmt -w -s channels/

vendor/github.com/weaveworks/mesh/BUILD.bazel

@@ -11,7 +11,7 @@ go_library(
         "logger.go",
         "overlay.go",
         "peer.go",
-        "peer_name_mac.go",
+        "peer_name_hash.go",
         "peers.go",
         "protocol.go",
         "protocol_crypto.go",

vendor/github.com/weaveworks/mesh/peer_name_hash.go

@@ -1,4 +1,4 @@
-// +build peer_name_hash
+// +build !peer_name_mac
 
 package mesh
 

vendor/github.com/weaveworks/mesh/peer_name_mac.go

@@ -1,110 +0,0 @@
-// +build peer_name_mac !peer_name_alternative
-
-package mesh
-
-// The !peer_name_alternative effectively makes this the default,
-// i.e. to choose an alternative, run
-//
-//   go build -tags 'peer_name_alternative peer_name_hash'
-//
-// Let peer names be MACs...
-//
-// MACs need to be unique across our network, or bad things will
-// happen anyway. So they make pretty good candidates for peer
-// names. And doing so is pretty efficient both computationally and
-// network overhead wise.
-//
-// Note that we do not mandate *what* MAC should be used as the peer
-// name. In particular it doesn't actually have to be the MAC of, say,
-// the network interface the peer is sniffing on.
-
-import (
-	"fmt"
-	"net"
-)
-
-// PeerName is used as a map key. Since net.HardwareAddr isn't suitable for
-// that - it's a slice, and slices can't be map keys - we convert that to/from
-// uint64.
-type PeerName uint64
-
-const (
-	// PeerNameFlavour is the type of peer names we use.
-	PeerNameFlavour = "mac"
-
-	// NameSize is the number of bytes in a peer name.
-	NameSize = 6
-
-	// UnknownPeerName is used as a sentinel value.
-	UnknownPeerName = PeerName(0)
-)
-
-// PeerNameFromUserInput parses PeerName from a user-provided string.
-func PeerNameFromUserInput(userInput string) (PeerName, error) {
-	return PeerNameFromString(userInput)
-}
-
-// PeerNameFromString parses PeerName from a generic string.
-func PeerNameFromString(nameStr string) (PeerName, error) {
-	var a, b, c, d, e, f uint64
-
-	match := func(format string, args ...interface{}) bool {
-		a, b, c, d, e, f = 0, 0, 0, 0, 0, 0
-		n, err := fmt.Sscanf(nameStr+"\000", format+"\000", args...)
-		return err == nil && n == len(args)
-	}
-
-	switch {
-	case match("%2x:%2x:%2x:%2x:%2x:%2x", &a, &b, &c, &d, &e, &f):
-	case match("::%2x:%2x:%2x:%2x", &c, &d, &e, &f):
-	case match("%2x::%2x:%2x:%2x", &a, &d, &e, &f):
-	case match("%2x:%2x::%2x:%2x", &a, &b, &e, &f):
-	case match("%2x:%2x:%2x::%2x", &a, &b, &c, &f):
-	case match("%2x:%2x:%2x:%2x::", &a, &b, &c, &d):
-	case match("::%2x:%2x:%2x", &d, &e, &f):
-	case match("%2x::%2x:%2x", &a, &e, &f):
-	case match("%2x:%2x::%2x", &a, &b, &f):
-	case match("%2x:%2x:%2x::", &a, &b, &c):
-	case match("::%2x:%2x", &e, &f):
-	case match("%2x::%2x", &a, &f):
-	case match("%2x:%2x::", &a, &b):
-	case match("::%2x", &f):
-	case match("%2x::", &a):
-	default:
-		return UnknownPeerName, fmt.Errorf("invalid peer name format: %q", nameStr)
-	}
-
-	return PeerName(a<<40 | b<<32 | c<<24 | d<<16 | e<<8 | f), nil
-}
-
-// PeerNameFromBin parses PeerName from a byte slice.
-func PeerNameFromBin(nameByte []byte) PeerName {
-	return PeerName(macint(net.HardwareAddr(nameByte)))
-}
-
-// bytes encodes PeerName as a byte slice.
-func (name PeerName) bytes() []byte {
-	return intmac(uint64(name))
-}
-
-// String encodes PeerName as a string.
-func (name PeerName) String() string {
-	return intmac(uint64(name)).String()
-}
-
-func macint(mac net.HardwareAddr) (r uint64) {
-	for _, b := range mac {
-		r <<= 8
-		r |= uint64(b)
-	}
-	return
-}
-
-func intmac(key uint64) (r net.HardwareAddr) {
-	r = make([]byte, 6)
-	for i := 5; i >= 0; i-- {
-		r[i] = byte(key)
-		key >>= 8
-	}
-	return
-}