rebase: bump golang.org/x/crypto from 0.3.0 to 0.4.0

Bumps [golang.org/x/crypto](https://github.com/golang/crypto) from 0.3.0 to 0.4.0.
- [Release notes](https://github.com/golang/crypto/releases)
- [Commits](https://github.com/golang/crypto/compare/v0.3.0...v0.4.0)

---
updated-dependencies:
- dependency-name: golang.org/x/crypto
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/golang.org/x/net/http2/hpack/encode.go

@@ -116,6 +116,11 @@ func (e *Encoder) SetMaxDynamicTableSize(v uint32) {
 	e.dynTab.setMaxSize(v)
 }
 
+// MaxDynamicTableSize returns the current dynamic header table size.
+func (e *Encoder) MaxDynamicTableSize() (v uint32) {
+	return e.dynTab.maxSize
+}
+
 // SetMaxDynamicTableSizeLimit changes the maximum value that can be
 // specified in SetMaxDynamicTableSize to v. By default, it is set to
 // 4096, which is the same size of the default dynamic header table

vendor/golang.org/x/net/http2/server.go

@@ -98,6 +98,19 @@ type Server struct {
 	// the HTTP/2 spec's recommendations.
 	MaxConcurrentStreams uint32
 
+	// MaxDecoderHeaderTableSize optionally specifies the http2
+	// SETTINGS_HEADER_TABLE_SIZE to send in the initial settings frame. It
+	// informs the remote endpoint of the maximum size of the header compression
+	// table used to decode header blocks, in octets. If zero, the default value
+	// of 4096 is used.
+	MaxDecoderHeaderTableSize uint32
+
+	// MaxEncoderHeaderTableSize optionally specifies an upper limit for the
+	// header compression table used for encoding request headers. Received
+	// SETTINGS_HEADER_TABLE_SIZE settings are capped at this limit. If zero,
+	// the default value of 4096 is used.
+	MaxEncoderHeaderTableSize uint32
+
 	// MaxReadFrameSize optionally specifies the largest frame
 	// this server is willing to read. A valid value is between
 	// 16k and 16M, inclusive. If zero or otherwise invalid, a
@@ -170,6 +183,20 @@ func (s *Server) maxConcurrentStreams() uint32 {
 	return defaultMaxStreams
 }
 
+func (s *Server) maxDecoderHeaderTableSize() uint32 {
+	if v := s.MaxDecoderHeaderTableSize; v > 0 {
+		return v
+	}
+	return initialHeaderTableSize
+}
+
+func (s *Server) maxEncoderHeaderTableSize() uint32 {
+	if v := s.MaxEncoderHeaderTableSize; v > 0 {
+		return v
+	}
+	return initialHeaderTableSize
+}
+
 // maxQueuedControlFrames is the maximum number of control frames like
 // SETTINGS, PING and RST_STREAM that will be queued for writing before
 // the connection is closed to prevent memory exhaustion attacks.
@@ -394,7 +421,6 @@ func (s *Server) ServeConn(c net.Conn, opts *ServeConnOpts) {
 		advMaxStreams:               s.maxConcurrentStreams(),
 		initialStreamSendWindowSize: initialWindowSize,
 		maxFrameSize:                initialMaxFrameSize,
-		headerTableSize:             initialHeaderTableSize,
 		serveG:                      newGoroutineLock(),
 		pushEnabled:                 true,
 		sawClientPreface:            opts.SawClientPreface,
@@ -424,12 +450,13 @@ func (s *Server) ServeConn(c net.Conn, opts *ServeConnOpts) {
 	sc.flow.add(initialWindowSize)
 	sc.inflow.add(initialWindowSize)
 	sc.hpackEncoder = hpack.NewEncoder(&sc.headerWriteBuf)
+	sc.hpackEncoder.SetMaxDynamicTableSizeLimit(s.maxEncoderHeaderTableSize())
 
 	fr := NewFramer(sc.bw, c)
 	if s.CountError != nil {
 		fr.countError = s.CountError
 	}
-	fr.ReadMetaHeaders = hpack.NewDecoder(initialHeaderTableSize, nil)
+	fr.ReadMetaHeaders = hpack.NewDecoder(s.maxDecoderHeaderTableSize(), nil)
 	fr.MaxHeaderListSize = sc.maxHeaderListSize()
 	fr.SetMaxReadFrameSize(s.maxReadFrameSize())
 	sc.framer = fr
@@ -559,7 +586,6 @@ type serverConn struct {
 	streams                     map[uint32]*stream
 	initialStreamSendWindowSize int32
 	maxFrameSize                int32
-	headerTableSize             uint32
 	peerMaxHeaderListSize       uint32            // zero means unknown (default)
 	canonHeader                 map[string]string // http2-lower-case -> Go-Canonical-Case
 	writingFrame                bool              // started writing a frame (on serve goroutine or separate)
@@ -864,6 +890,7 @@ func (sc *serverConn) serve() {
 			{SettingMaxFrameSize, sc.srv.maxReadFrameSize()},
 			{SettingMaxConcurrentStreams, sc.advMaxStreams},
 			{SettingMaxHeaderListSize, sc.maxHeaderListSize()},
+			{SettingHeaderTableSize, sc.srv.maxDecoderHeaderTableSize()},
 			{SettingInitialWindowSize, uint32(sc.srv.initialStreamRecvWindowSize())},
 		},
 	})
@@ -1661,7 +1688,6 @@ func (sc *serverConn) processSetting(s Setting) error {
 	}
 	switch s.ID {
 	case SettingHeaderTableSize:
-		sc.headerTableSize = s.Val
 		sc.hpackEncoder.SetMaxDynamicTableSize(s.Val)
 	case SettingEnablePush:
 		sc.pushEnabled = s.Val != 0

vendor/golang.org/x/net/http2/transport.go

@@ -118,6 +118,28 @@ type Transport struct {
 	// to mean no limit.
 	MaxHeaderListSize uint32
 
+	// MaxReadFrameSize is the http2 SETTINGS_MAX_FRAME_SIZE to send in the
+	// initial settings frame. It is the size in bytes of the largest frame
+	// payload that the sender is willing to receive. If 0, no setting is
+	// sent, and the value is provided by the peer, which should be 16384
+	// according to the spec:
+	// https://datatracker.ietf.org/doc/html/rfc7540#section-6.5.2.
+	// Values are bounded in the range 16k to 16M.
+	MaxReadFrameSize uint32
+
+	// MaxDecoderHeaderTableSize optionally specifies the http2
+	// SETTINGS_HEADER_TABLE_SIZE to send in the initial settings frame. It
+	// informs the remote endpoint of the maximum size of the header compression
+	// table used to decode header blocks, in octets. If zero, the default value
+	// of 4096 is used.
+	MaxDecoderHeaderTableSize uint32
+
+	// MaxEncoderHeaderTableSize optionally specifies an upper limit for the
+	// header compression table used for encoding request headers. Received
+	// SETTINGS_HEADER_TABLE_SIZE settings are capped at this limit. If zero,
+	// the default value of 4096 is used.
+	MaxEncoderHeaderTableSize uint32
+
 	// StrictMaxConcurrentStreams controls whether the server's
 	// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
 	// globally. If false, new TCP connections are created to the
@@ -171,6 +193,19 @@ func (t *Transport) maxHeaderListSize() uint32 {
 	return t.MaxHeaderListSize
 }
 
+func (t *Transport) maxFrameReadSize() uint32 {
+	if t.MaxReadFrameSize == 0 {
+		return 0 // use the default provided by the peer
+	}
+	if t.MaxReadFrameSize < minMaxFrameSize {
+		return minMaxFrameSize
+	}
+	if t.MaxReadFrameSize > maxFrameSize {
+		return maxFrameSize
+	}
+	return t.MaxReadFrameSize
+}
+
 func (t *Transport) disableCompression() bool {
 	return t.DisableCompression || (t.t1 != nil && t.t1.DisableCompression)
 }
@@ -293,10 +328,11 @@ type ClientConn struct {
 	lastActive      time.Time
 	lastIdle        time.Time // time last idle
 	// Settings from peer: (also guarded by wmu)
-	maxFrameSize          uint32
-	maxConcurrentStreams  uint32
-	peerMaxHeaderListSize uint64
-	initialWindowSize     uint32
+	maxFrameSize           uint32
+	maxConcurrentStreams   uint32
+	peerMaxHeaderListSize  uint64
+	peerMaxHeaderTableSize uint32
+	initialWindowSize      uint32
 
 	// reqHeaderMu is a 1-element semaphore channel controlling access to sending new requests.
 	// Write to reqHeaderMu to lock it, read from it to unlock.
@@ -681,6 +717,20 @@ func (t *Transport) expectContinueTimeout() time.Duration {
 	return t.t1.ExpectContinueTimeout
 }
 
+func (t *Transport) maxDecoderHeaderTableSize() uint32 {
+	if v := t.MaxDecoderHeaderTableSize; v > 0 {
+		return v
+	}
+	return initialHeaderTableSize
+}
+
+func (t *Transport) maxEncoderHeaderTableSize() uint32 {
+	if v := t.MaxEncoderHeaderTableSize; v > 0 {
+		return v
+	}
+	return initialHeaderTableSize
+}
+
 func (t *Transport) NewClientConn(c net.Conn) (*ClientConn, error) {
 	return t.newClientConn(c, t.disableKeepAlives())
 }
@@ -721,15 +771,19 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 	})
 	cc.br = bufio.NewReader(c)
 	cc.fr = NewFramer(cc.bw, cc.br)
+	if t.maxFrameReadSize() != 0 {
+		cc.fr.SetMaxReadFrameSize(t.maxFrameReadSize())
+	}
 	if t.CountError != nil {
 		cc.fr.countError = t.CountError
 	}
-	cc.fr.ReadMetaHeaders = hpack.NewDecoder(initialHeaderTableSize, nil)
+	maxHeaderTableSize := t.maxDecoderHeaderTableSize()
+	cc.fr.ReadMetaHeaders = hpack.NewDecoder(maxHeaderTableSize, nil)
 	cc.fr.MaxHeaderListSize = t.maxHeaderListSize()
 
-	// TODO: SetMaxDynamicTableSize, SetMaxDynamicTableSizeLimit on
-	// henc in response to SETTINGS frames?
 	cc.henc = hpack.NewEncoder(&cc.hbuf)
+	cc.henc.SetMaxDynamicTableSizeLimit(t.maxEncoderHeaderTableSize())
+	cc.peerMaxHeaderTableSize = initialHeaderTableSize
 
 	if t.AllowHTTP {
 		cc.nextStreamID = 3
@@ -744,9 +798,15 @@ func (t *Transport) newClientConn(c net.Conn, singleUse bool) (*ClientConn, erro
 		{ID: SettingEnablePush, Val: 0},
 		{ID: SettingInitialWindowSize, Val: transportDefaultStreamFlow},
 	}
+	if max := t.maxFrameReadSize(); max != 0 {
+		initialSettings = append(initialSettings, Setting{ID: SettingMaxFrameSize, Val: max})
+	}
 	if max := t.maxHeaderListSize(); max != 0 {
 		initialSettings = append(initialSettings, Setting{ID: SettingMaxHeaderListSize, Val: max})
 	}
+	if maxHeaderTableSize != initialHeaderTableSize {
+		initialSettings = append(initialSettings, Setting{ID: SettingHeaderTableSize, Val: maxHeaderTableSize})
+	}
 
 	cc.bw.Write(clientPreface)
 	cc.fr.WriteSettings(initialSettings...)
@@ -2773,8 +2833,10 @@ func (rl *clientConnReadLoop) processSettingsNoWrite(f *SettingsFrame) error {
 			cc.cond.Broadcast()
 
 			cc.initialWindowSize = s.Val
+		case SettingHeaderTableSize:
+			cc.henc.SetMaxDynamicTableSize(s.Val)
+			cc.peerMaxHeaderTableSize = s.Val
 		default:
-			// TODO(bradfitz): handle more settings? SETTINGS_HEADER_TABLE_SIZE probably.
 			cc.vlogf("Unhandled Setting: %v", s)
 		}
 		return nil