core: Implement socket activation listeners (#6573)

* caddy adapt for listen_protocols

* adapt listen_socket

* allow multiple listen sockets for port ranges and readd socket fd listen logic

* readd logic to start servers according to listener protocols

* gofmt

* adapt caddytest

* gosec

* fmt and rename listen to listenWithSocket

* fmt and rename listen to listenWithSocket

* more consistent error msg

* non unix listenReusableWithSocketFile

* remove unused func

* doc comment typo

* nonosec

* commit

* doc comments

* more doc comments

* comment was misleading, cardinality did not change

* addressesWithProtocols

* update test

* fd/ and fdgram/

* rm addr

* actually write...

* i guess we doin' "skip": now

* wrong var in placeholder

* wrong var in placeholder II

* update param name in comment

* dont save nil file pointers

* windows

* key -> parsedKey

* osx

* multiple default_bind with protocols

* check for h1 and h2 listener netw

1 files changed, 177 insertions, 105 deletions

diff --git a/caddyconfig/httpcaddyfile/addresses.go b/caddyconfig/httpcaddyfile/addresses.go
index da51fe9b0..1c331eadc 100644
--- a/caddyconfig/httpcaddyfile/addresses.go
+++ b/caddyconfig/httpcaddyfile/addresses.go
@@ -77,10 +77,15 @@ import (
 // repetition may be undesirable, so call consolidateAddrMappings() to map
 // multiple addresses to the same lists of server blocks (a many:many mapping).
 // (Doing this is essentially a map-reduce technique.)
-func (st *ServerType) mapAddressToServerBlocks(originalServerBlocks []serverBlock,
+func (st *ServerType) mapAddressToProtocolToServerBlocks(originalServerBlocks []serverBlock,
 	options map[string]any,
-) (map[string][]serverBlock, error) {
-	sbmap := make(map[string][]serverBlock)
+) (map[string]map[string][]serverBlock, error) {
+	addrToProtocolToServerBlocks := map[string]map[string][]serverBlock{}
+
+	type keyWithParsedKey struct {
+		key       caddyfile.Token
+		parsedKey Address
+	}
 
 	for i, sblock := range originalServerBlocks {
 		// within a server block, we need to map all the listener addresses
@@ -88,27 +93,48 @@ func (st *ServerType) mapAddressToServerBlocks(originalServerBlocks []serverBloc
 		// will be served by them; this has the effect of treating each
 		// key of a server block as its own, but without having to repeat its
 		// contents in cases where multiple keys really can be served together
-		addrToKeys := make(map[string][]caddyfile.Token)
+		addrToProtocolToKeyWithParsedKeys := map[string]map[string][]keyWithParsedKey{}
 		for j, key := range sblock.block.Keys {
+			parsedKey, err := ParseAddress(key.Text)
+			if err != nil {
+				return nil, fmt.Errorf("parsing key: %v", err)
+			}
+			parsedKey = parsedKey.Normalize()
+
 			// a key can have multiple listener addresses if there are multiple
 			// arguments to the 'bind' directive (although they will all have
 			// the same port, since the port is defined by the key or is implicit
 			// through automatic HTTPS)
-			addrs, err := st.listenerAddrsForServerBlockKey(sblock, key.Text, options)
+			listeners, err := st.listenersForServerBlockAddress(sblock, parsedKey, options)
 			if err != nil {
 				return nil, fmt.Errorf("server block %d, key %d (%s): determining listener address: %v", i, j, key.Text, err)
 			}
 
-			// associate this key with each listener address it is served on
-			for _, addr := range addrs {
-				addrToKeys[addr] = append(addrToKeys[addr], key)
+			// associate this key with its protocols and each listener address served with them
+			kwpk := keyWithParsedKey{key, parsedKey}
+			for addr, protocols := range listeners {
+				protocolToKeyWithParsedKeys, ok := addrToProtocolToKeyWithParsedKeys[addr]
+				if !ok {
+					protocolToKeyWithParsedKeys = map[string][]keyWithParsedKey{}
+					addrToProtocolToKeyWithParsedKeys[addr] = protocolToKeyWithParsedKeys
+				}
+
+				// an empty protocol indicates the default, a nil or empty value in the ListenProtocols array
+				if len(protocols) == 0 {
+					protocols[""] = struct{}{}
+				}
+				for prot := range protocols {
+					protocolToKeyWithParsedKeys[prot] = append(
+						protocolToKeyWithParsedKeys[prot],
+						kwpk)
+				}
 			}
 		}
 
 		// make a slice of the map keys so we can iterate in sorted order
-		addrs := make([]string, 0, len(addrToKeys))
-		for k := range addrToKeys {
-			addrs = append(addrs, k)
+		addrs := make([]string, 0, len(addrToProtocolToKeyWithParsedKeys))
+		for addr := range addrToProtocolToKeyWithParsedKeys {
+			addrs = append(addrs, addr)
 		}
 		sort.Strings(addrs)
 
@@ -118,85 +144,132 @@ func (st *ServerType) mapAddressToServerBlocks(originalServerBlocks []serverBloc
 		// server block are only the ones which use the address; but
 		// the contents (tokens) are of course the same
 		for _, addr := range addrs {
-			keys := addrToKeys[addr]
-			// parse keys so that we only have to do it once
-			parsedKeys := make([]Address, 0, len(keys))
-			for _, key := range keys {
-				addr, err := ParseAddress(key.Text)
-				if err != nil {
-					return nil, fmt.Errorf("parsing key '%s': %v", key.Text, err)
+			protocolToKeyWithParsedKeys := addrToProtocolToKeyWithParsedKeys[addr]
+
+			prots := make([]string, 0, len(protocolToKeyWithParsedKeys))
+			for prot := range protocolToKeyWithParsedKeys {
+				prots = append(prots, prot)
+			}
+			sort.Strings(prots)
+
+			protocolToServerBlocks, ok := addrToProtocolToServerBlocks[addr]
+			if !ok {
+				protocolToServerBlocks = map[string][]serverBlock{}
+				addrToProtocolToServerBlocks[addr] = protocolToServerBlocks
+			}
+
+			for _, prot := range prots {
+				keyWithParsedKeys := protocolToKeyWithParsedKeys[prot]
+
+				keys := make([]caddyfile.Token, len(keyWithParsedKeys))
+				parsedKeys := make([]Address, len(keyWithParsedKeys))
+
+				for k, keyWithParsedKey := range keyWithParsedKeys {
+					keys[k] = keyWithParsedKey.key
+					parsedKeys[k] = keyWithParsedKey.parsedKey
 				}
-				parsedKeys = append(parsedKeys, addr.Normalize())
+
+				protocolToServerBlocks[prot] = append(protocolToServerBlocks[prot], serverBlock{
+					block: caddyfile.ServerBlock{
+						Keys:     keys,
+						Segments: sblock.block.Segments,
+					},
+					pile:       sblock.pile,
+					parsedKeys: parsedKeys,
+				})
 			}
-			sbmap[addr] = append(sbmap[addr], serverBlock{
-				block: caddyfile.ServerBlock{
-					Keys:     keys,
-					Segments: sblock.block.Segments,
-				},
-				pile: sblock.pile,
-				keys: parsedKeys,
-			})
 		}
 	}
 
-	return sbmap, nil
+	return addrToProtocolToServerBlocks, nil
 }
 
 // consolidateAddrMappings eliminates repetition of identical server blocks in a mapping of
-// single listener addresses to lists of server blocks. Since multiple addresses may serve
-// identical sites (server block contents), this function turns a 1:many mapping into a
-// many:many mapping. Server block contents (tokens) must be exactly identical so that
-// reflect.DeepEqual returns true in order for the addresses to be combined. Identical
-// entries are deleted from the addrToServerBlocks map. Essentially, each pairing (each
+// single listener addresses to protocols to lists of server blocks. Since multiple addresses
+// may serve multiple protocols to identical sites (server block contents), this function turns
+// a 1:many mapping into a many:many mapping. Server block contents (tokens) must be
+// exactly identical so that reflect.DeepEqual returns true in order for the addresses to be combined.
+// Identical entries are deleted from the addrToServerBlocks map. Essentially, each pairing (each
 // association from multiple addresses to multiple server blocks; i.e. each element of
 // the returned slice) becomes a server definition in the output JSON.
-func (st *ServerType) consolidateAddrMappings(addrToServerBlocks map[string][]serverBlock) []sbAddrAssociation {
-	sbaddrs := make([]sbAddrAssociation, 0, len(addrToServerBlocks))
-	for addr, sblocks := range addrToServerBlocks {
-		// we start with knowing that at least this address
-		// maps to these server blocks
-		a := sbAddrAssociation{
-			addresses:    []string{addr},
-			serverBlocks: sblocks,
+func (st *ServerType) consolidateAddrMappings(addrToProtocolToServerBlocks map[string]map[string][]serverBlock) []sbAddrAssociation {
+	sbaddrs := make([]sbAddrAssociation, 0, len(addrToProtocolToServerBlocks))
+
+	addrs := make([]string, 0, len(addrToProtocolToServerBlocks))
+	for addr := range addrToProtocolToServerBlocks {
+		addrs = append(addrs, addr)
+	}
+	sort.Strings(addrs)
+
+	for _, addr := range addrs {
+		protocolToServerBlocks := addrToProtocolToServerBlocks[addr]
+
+		prots := make([]string, 0, len(protocolToServerBlocks))
+		for prot := range protocolToServerBlocks {
+			prots = append(prots, prot)
 		}
+		sort.Strings(prots)
+
+		for _, prot := range prots {
+			serverBlocks := protocolToServerBlocks[prot]
+
+			// now find other addresses that map to identical
+			// server blocks and add them to our map of listener
+			// addresses and protocols, while removing them from
+			// the original map
+			listeners := map[string]map[string]struct{}{}
+
+			for otherAddr, otherProtocolToServerBlocks := range addrToProtocolToServerBlocks {
+				for otherProt, otherServerBlocks := range otherProtocolToServerBlocks {
+					if addr == otherAddr && prot == otherProt || reflect.DeepEqual(serverBlocks, otherServerBlocks) {
+						listener, ok := listeners[otherAddr]
+						if !ok {
+							listener = map[string]struct{}{}
+							listeners[otherAddr] = listener
+						}
+						listener[otherProt] = struct{}{}
+						delete(otherProtocolToServerBlocks, otherProt)
+					}
+				}
+			}
 
-		// now find other addresses that map to identical
-		// server blocks and add them to our list of
-		// addresses, while removing them from the map
-		for otherAddr, otherSblocks := range addrToServerBlocks {
-			if addr == otherAddr {
-				continue
+			addresses := make([]string, 0, len(listeners))
+			for lnAddr := range listeners {
+				addresses = append(addresses, lnAddr)
 			}
-			if reflect.DeepEqual(sblocks, otherSblocks) {
-				a.addresses = append(a.addresses, otherAddr)
-				delete(addrToServerBlocks, otherAddr)
+			sort.Strings(addresses)
+
+			addressesWithProtocols := make([]addressWithProtocols, 0, len(listeners))
+
+			for _, lnAddr := range addresses {
+				lnProts := listeners[lnAddr]
+				prots := make([]string, 0, len(lnProts))
+				for prot := range lnProts {
+					prots = append(prots, prot)
+				}
+				sort.Strings(prots)
+
+				addressesWithProtocols = append(addressesWithProtocols, addressWithProtocols{
+					address:   lnAddr,
+					protocols: prots,
+				})
 			}
-		}
-		sort.Strings(a.addresses)
 
-		sbaddrs = append(sbaddrs, a)
+			sbaddrs = append(sbaddrs, sbAddrAssociation{
+				addressesWithProtocols: addressesWithProtocols,
+				serverBlocks:           serverBlocks,
+			})
+		}
 	}
 
-	// sort them by their first address (we know there will always be at least one)
-	// to avoid problems with non-deterministic ordering (makes tests flaky)
-	sort.Slice(sbaddrs, func(i, j int) bool {
-		return sbaddrs[i].addresses[0] < sbaddrs[j].addresses[0]
-	})
-
 	return sbaddrs
 }
 
-// listenerAddrsForServerBlockKey essentially converts the Caddyfile
-// site addresses to Caddy listener addresses for each server block.
-func (st *ServerType) listenerAddrsForServerBlockKey(sblock serverBlock, key string,
+// listenersForServerBlockAddress essentially converts the Caddyfile site addresses to a map from
+// Caddy listener addresses and the protocols to serve them with to the parsed address for each server block.
+func (st *ServerType) listenersForServerBlockAddress(sblock serverBlock, addr Address,
 	options map[string]any,
-) ([]string, error) {
-	addr, err := ParseAddress(key)
-	if err != nil {
-		return nil, fmt.Errorf("parsing key: %v", err)
-	}
-	addr = addr.Normalize()
-
+) (map[string]map[string]struct{}, error) {
 	switch addr.Scheme {
 	case "wss":
 		return nil, fmt.Errorf("the scheme wss:// is only supported in browsers; use https:// instead")
@@ -230,55 +303,54 @@ func (st *ServerType) listenerAddrsForServerBlockKey(sblock serverBlock, key str
 
 	// error if scheme and port combination violate convention
 	if (addr.Scheme == "http" && lnPort == httpsPort) || (addr.Scheme == "https" && lnPort == httpPort) {
-		return nil, fmt.Errorf("[%s] scheme and port violate convention", key)
+		return nil, fmt.Errorf("[%s] scheme and port violate convention", addr.String())
 	}
 
-	// the bind directive specifies hosts (and potentially network), but is optional
-	lnHosts := make([]string, 0, len(sblock.pile["bind"]))
+	// the bind directive specifies hosts (and potentially network), and the protocols to serve them with, but is optional
+	lnCfgVals := make([]addressesWithProtocols, 0, len(sblock.pile["bind"]))
 	for _, cfgVal := range sblock.pile["bind"] {
-		lnHosts = append(lnHosts, cfgVal.Value.([]string)...)
+		if val, ok := cfgVal.Value.(addressesWithProtocols); ok {
+			lnCfgVals = append(lnCfgVals, val)
+		}
 	}
-	if len(lnHosts) == 0 {
-		if defaultBind, ok := options["default_bind"].([]string); ok {
-			lnHosts = defaultBind
+	if len(lnCfgVals) == 0 {
+		if defaultBindValues, ok := options["default_bind"].([]ConfigValue); ok {
+			for _, defaultBindValue := range defaultBindValues {
+				lnCfgVals = append(lnCfgVals, defaultBindValue.Value.(addressesWithProtocols))
+			}
 		} else {
-			lnHosts = []string{""}
+			lnCfgVals = []addressesWithProtocols{{
+				addresses: []string{""},
+				protocols: nil,
+			}}
 		}
 	}
 
 	// use a map to prevent duplication
-	listeners := make(map[string]struct{})
-	for _, lnHost := range lnHosts {
-		// normally we would simply append the port,
-		// but if lnHost is IPv6, we need to ensure it
-		// is enclosed in [ ]; net.JoinHostPort does
-		// this for us, but lnHost might also have a
-		// network type in front (e.g. "tcp/") leading
-		// to "[tcp/::1]" which causes parsing failures
-		// later; what we need is "tcp/[::1]", so we have
-		// to split the network and host, then re-combine
-		network, host, ok := strings.Cut(lnHost, "/")
-		if !ok {
-			host = network
-			network = ""
-		}
-		host = strings.Trim(host, "[]") // IPv6
-		networkAddr := caddy.JoinNetworkAddress(network, host, lnPort)
-		addr, err := caddy.ParseNetworkAddress(networkAddr)
-		if err != nil {
-			return nil, fmt.Errorf("parsing network address: %v", err)
+	listeners := map[string]map[string]struct{}{}
+	for _, lnCfgVal := range lnCfgVals {
+		for _, lnHost := range lnCfgVal.addresses {
+			networkAddr, err := caddy.ParseNetworkAddressFromHostPort(lnHost, lnPort)
+			if err != nil {
+				return nil, fmt.Errorf("parsing network address: %v", err)
+			}
+			if _, ok := listeners[addr.String()]; !ok {
+				listeners[networkAddr.String()] = map[string]struct{}{}
+			}
+			for _, protocol := range lnCfgVal.protocols {
+				listeners[networkAddr.String()][protocol] = struct{}{}
+			}
 		}
-		listeners[addr.String()] = struct{}{}
 	}
 
-	// now turn map into list
-	listenersList := make([]string, 0, len(listeners))
-	for lnStr := range listeners {
-		listenersList = append(listenersList, lnStr)
-	}
-	sort.Strings(listenersList)
+	return listeners, nil
+}
 
-	return listenersList, nil
+// addressesWithProtocols associates a list of listen addresses
+// with a list of protocols to serve them with
+type addressesWithProtocols struct {
+	addresses []string
+	protocols []string
 }
 
 // Address represents a site address. It contains