Vendor after merging mtrmac/image:openpgp, + other updates

Primarily vendor after merging mtrmac/image:openpgp.

Then update for the SigningMechanism API change.

Also skip signing tests if the GPG mechanism does not support signing.

Also abort some of the tests early instead of trying to use invalid (or
nil) values.

The current master of image-tools does not build with Go 1.6, so keep
using an older release.

Also requires adding a few more dependencies of our updated
dependencies.

vendor/github.com/docker/distribution/context/doc.go

@@ -64,7 +64,7 @@
 // Note that this only affects the new context, the previous context, with the
 // version field, can be used independently. Put another way, the new logger,
 // added to the request context, is unique to that context and can have
-// request scoped varaibles.
+// request scoped variables.
 //
 // HTTP Requests
 //

vendor/github.com/docker/distribution/registry/api/v2/urls.go

@@ -1,10 +1,9 @@
 package v2
 
 import (
-	"net"
+	"fmt"
 	"net/http"
 	"net/url"
-	"strconv"
 	"strings"
 
 	"github.com/docker/distribution/reference"
@@ -48,66 +47,42 @@ func NewURLBuilderFromString(root string, relative bool) (*URLBuilder, error) {
 // NewURLBuilderFromRequest uses information from an *http.Request to
 // construct the root url.
 func NewURLBuilderFromRequest(r *http.Request, relative bool) *URLBuilder {
-	var scheme string
-
-	forwardedProto := r.Header.Get("X-Forwarded-Proto")
-	// TODO: log the error
-	forwardedHeader, _, _ := parseForwardedHeader(r.Header.Get("Forwarded"))
-
-	switch {
-	case len(forwardedProto) > 0:
-		scheme = forwardedProto
-	case len(forwardedHeader["proto"]) > 0:
-		scheme = forwardedHeader["proto"]
-	case r.TLS != nil:
-		scheme = "https"
-	case len(r.URL.Scheme) > 0:
-		scheme = r.URL.Scheme
-	default:
+	var (
 		scheme = "http"
+		host   = r.Host
+	)
+
+	if r.TLS != nil {
+		scheme = "https"
+	} else if len(r.URL.Scheme) > 0 {
+		scheme = r.URL.Scheme
 	}
 
-	host := r.Host
-
-	if forwardedHost := r.Header.Get("X-Forwarded-Host"); len(forwardedHost) > 0 {
-		// According to the Apache mod_proxy docs, X-Forwarded-Host can be a
-		// comma-separated list of hosts, to which each proxy appends the
-		// requested host. We want to grab the first from this comma-separated
-		// list.
-		hosts := strings.SplitN(forwardedHost, ",", 2)
-		host = strings.TrimSpace(hosts[0])
-	} else if addr, exists := forwardedHeader["for"]; exists {
-		host = addr
-	} else if h, exists := forwardedHeader["host"]; exists {
-		host = h
-	}
-
-	portLessHost, port := host, ""
-	if !isIPv6Address(portLessHost) {
-		// with go 1.6, this would treat the last part of IPv6 address as a port
-		portLessHost, port, _ = net.SplitHostPort(host)
-	}
-	if forwardedPort := r.Header.Get("X-Forwarded-Port"); len(port) == 0 && len(forwardedPort) > 0 {
-		ports := strings.SplitN(forwardedPort, ",", 2)
-		forwardedPort = strings.TrimSpace(ports[0])
-		if _, err := strconv.ParseInt(forwardedPort, 10, 32); err == nil {
-			port = forwardedPort
+	// Handle fowarded headers
+	// Prefer "Forwarded" header as defined by rfc7239 if given
+	// see https://tools.ietf.org/html/rfc7239
+	if forwarded := r.Header.Get("Forwarded"); len(forwarded) > 0 {
+		forwardedHeader, _, err := parseForwardedHeader(forwarded)
+		if err == nil {
+			if fproto := forwardedHeader["proto"]; len(fproto) > 0 {
+				scheme = fproto
+			}
+			if fhost := forwardedHeader["host"]; len(fhost) > 0 {
+				host = fhost
+			}
 		}
-	}
-
-	if len(portLessHost) > 0 {
-		host = portLessHost
-	}
-	if len(port) > 0 {
-		// remove enclosing brackets of ipv6 address otherwise they will be duplicated
-		if len(host) > 1 && host[0] == '[' && host[len(host)-1] == ']' {
-			host = host[1 : len(host)-1]
+	} else {
+		if forwardedProto := r.Header.Get("X-Forwarded-Proto"); len(forwardedProto) > 0 {
+			scheme = forwardedProto
+		}
+		if forwardedHost := r.Header.Get("X-Forwarded-Host"); len(forwardedHost) > 0 {
+			// According to the Apache mod_proxy docs, X-Forwarded-Host can be a
+			// comma-separated list of hosts, to which each proxy appends the
+			// requested host. We want to grab the first from this comma-separated
+			// list.
+			hosts := strings.SplitN(forwardedHost, ",", 2)
+			host = strings.TrimSpace(hosts[0])
 		}
-		// JoinHostPort properly encloses ipv6 addresses in square brackets
-		host = net.JoinHostPort(host, port)
-	} else if isIPv6Address(host) && host[0] != '[' {
-		// ipv6 needs to be enclosed in square brackets in urls
-		host = "[" + host + "]"
 	}
 
 	basePath := routeDescriptorsMap[RouteNameBase].Path
@@ -175,6 +150,8 @@ func (ub *URLBuilder) BuildManifestURL(ref reference.Named) (string, error) {
 		tagOrDigest = v.Tag()
 	case reference.Digested:
 		tagOrDigest = v.Digest().String()
+	default:
+		return "", fmt.Errorf("reference must have a tag or digest")
 	}
 
 	manifestURL, err := route.URL("name", ref.Name(), "reference", tagOrDigest)
@@ -287,28 +264,3 @@ func appendValues(u string, values ...url.Values) string {
 
 	return appendValuesURL(up, values...).String()
 }
-
-// isIPv6Address returns true if given string is a valid IPv6 address. No port is allowed. The address may be
-// enclosed in square brackets.
-func isIPv6Address(host string) bool {
-	if len(host) > 1 && host[0] == '[' && host[len(host)-1] == ']' {
-		host = host[1 : len(host)-1]
-	}
-	// The IPv6 scoped addressing zone identifier starts after the last percent sign.
-	if i := strings.LastIndexByte(host, '%'); i > 0 {
-		host = host[:i]
-	}
-	ip := net.ParseIP(host)
-	if ip == nil {
-		return false
-	}
-	if ip.To16() == nil {
-		return false
-	}
-	if ip.To4() == nil {
-		return true
-	}
-	// dot can be present in ipv4-mapped address, it needs to come after a colon though
-	i := strings.IndexAny(host, ":.")
-	return i >= 0 && host[i] == ':'
-}