Use h2c from x/net to handle h2c requests

Co-authored-by: Mathieu Lonjaret <mathieu.lonjaret@gmail.com>

vendor/golang.org/x/net/publicsuffix/gen.go

@@ -100,6 +100,7 @@ var (
 	labelsList    = []string{}
 	labelsMap     = map[string]bool{}
 	rules         = []string{}
+	numICANNRules = 0
 
 	// validSuffixRE is used to check that the entries in the public suffix
 	// list are in canonical form (after Punycode encoding). Specifically,
@@ -167,11 +168,14 @@ func main1() error {
 		}
 		s = strings.TrimSpace(s)
 		if strings.Contains(s, "BEGIN ICANN DOMAINS") {
+			if len(rules) != 0 {
+				return fmt.Errorf(`expected no rules before "BEGIN ICANN DOMAINS"`)
+			}
 			icann = true
 			continue
 		}
 		if strings.Contains(s, "END ICANN DOMAINS") {
-			icann = false
+			icann, numICANNRules = false, len(rules)
 			continue
 		}
 		if s == "" || strings.HasPrefix(s, "//") {
@@ -287,7 +291,7 @@ func gitCommit() (sha, date string, retErr error) {
 
 func printTest(w io.Writer, n *node) error {
 	fmt.Fprintf(w, "// generated by go run gen.go; DO NOT EDIT\n\n")
-	fmt.Fprintf(w, "package publicsuffix\n\nvar rules = [...]string{\n")
+	fmt.Fprintf(w, "package publicsuffix\n\nconst numICANNRules = %d\n\nvar rules = [...]string{\n", numICANNRules)
 	for _, rule := range rules {
 		fmt.Fprintf(w, "%q,\n", rule)
 	}

vendor/golang.org/x/net/publicsuffix/list.go

@@ -5,8 +5,43 @@
 //go:generate go run gen.go
 
 // Package publicsuffix provides a public suffix list based on data from
-// http://publicsuffix.org/. A public suffix is one under which Internet users
-// can directly register names.
+// https://publicsuffix.org/
+//
+// A public suffix is one under which Internet users can directly register
+// names. It is related to, but different from, a TLD (top level domain).
+//
+// "com" is a TLD (top level domain). Top level means it has no dots.
+//
+// "com" is also a public suffix. Amazon and Google have registered different
+// siblings under that domain: "amazon.com" and "google.com".
+//
+// "au" is another TLD, again because it has no dots. But it's not "amazon.au".
+// Instead, it's "amazon.com.au".
+//
+// "com.au" isn't an actual TLD, because it's not at the top level (it has
+// dots). But it is an eTLD (effective TLD), because that's the branching point
+// for domain name registrars.
+//
+// Another name for "an eTLD" is "a public suffix". Often, what's more of
+// interest is the eTLD+1, or one more label than the public suffix. For
+// example, browsers partition read/write access to HTTP cookies according to
+// the eTLD+1. Web pages served from "amazon.com.au" can't read cookies from
+// "google.com.au", but web pages served from "maps.google.com" can share
+// cookies from "www.google.com", so you don't have to sign into Google Maps
+// separately from signing into Google Web Search. Note that all four of those
+// domains have 3 labels and 2 dots. The first two domains are each an eTLD+1,
+// the last two are not (but share the same eTLD+1: "google.com").
+//
+// All of these domains have the same eTLD+1:
+//  - "www.books.amazon.co.uk"
+//  - "books.amazon.co.uk"
+//  - "amazon.co.uk"
+// Specifically, the eTLD+1 is "amazon.co.uk", because the eTLD is "co.uk".
+//
+// There is no closed form algorithm to calculate the eTLD of a domain.
+// Instead, the calculation is data driven. This package provides a
+// pre-compiled snapshot of Mozilla's PSL (Public Suffix List) data at
+// https://publicsuffix.org/
 package publicsuffix // import "golang.org/x/net/publicsuffix"
 
 // TODO: specify case sensitivity and leading/trailing dot behavior for
@@ -37,20 +72,24 @@ func (list) String() string {
 // publicsuffix.org database compiled into the library.
 //
 // icann is whether the public suffix is managed by the Internet Corporation
-// for Assigned Names and Numbers. If not, the public suffix is privately
-// managed. For example, foo.org and foo.co.uk are ICANN domains,
-// foo.dyndns.org and foo.blogspot.co.uk are private domains.
+// for Assigned Names and Numbers. If not, the public suffix is either a
+// privately managed domain (and in practice, not a top level domain) or an
+// unmanaged top level domain (and not explicitly mentioned in the
+// publicsuffix.org list). For example, "foo.org" and "foo.co.uk" are ICANN
+// domains, "foo.dyndns.org" and "foo.blogspot.co.uk" are private domains and
+// "cromulent" is an unmanaged top level domain.
 //
-// Use cases for distinguishing ICANN domains like foo.com from private
-// domains like foo.appspot.com can be found at
+// Use cases for distinguishing ICANN domains like "foo.com" from private
+// domains like "foo.appspot.com" can be found at
 // https://wiki.mozilla.org/Public_Suffix_List/Use_Cases
 func PublicSuffix(domain string) (publicSuffix string, icann bool) {
 	lo, hi := uint32(0), uint32(numTLD)
-	s, suffix, wildcard := domain, len(domain), false
+	s, suffix, icannNode, wildcard := domain, len(domain), false, false
 loop:
 	for {
 		dot := strings.LastIndex(s, ".")
 		if wildcard {
+			icann = icannNode
 			suffix = 1 + dot
 		}
 		if lo == hi {
@@ -62,7 +101,7 @@ loop:
 		}
 
 		u := nodes[f] >> (nodesBitsTextOffset + nodesBitsTextLength)
-		icann = u&(1<<nodesBitsICANN-1) != 0
+		icannNode = u&(1<<nodesBitsICANN-1) != 0
 		u >>= nodesBitsICANN
 		u = children[u&(1<<nodesBitsChildren-1)]
 		lo = u & (1<<childrenBitsLo - 1)
@@ -78,6 +117,9 @@ loop:
 		}
 		u >>= childrenBitsNodeType
 		wildcard = u&(1<<childrenBitsWildcard-1) != 0
+		if !wildcard {
+			icann = icannNode
+		}
 
 		if dot == -1 {
 			break
@@ -123,6 +165,10 @@ func nodeLabel(i uint32) string {
 // EffectiveTLDPlusOne returns the effective top level domain plus one more
 // label. For example, the eTLD+1 for "foo.bar.golang.org" is "golang.org".
 func EffectiveTLDPlusOne(domain string) (string, error) {
+	if strings.HasPrefix(domain, ".") || strings.HasSuffix(domain, ".") || strings.Contains(domain, "..") {
+		return "", fmt.Errorf("publicsuffix: empty label in domain %q", domain)
+	}
+
 	suffix, _ := PublicSuffix(domain)
 	if len(domain) <= len(suffix) {
 		return "", fmt.Errorf("publicsuffix: cannot derive eTLD+1 for domain %q", domain)