diff --git a/api/api.go b/api/api.go
index 6fcaef0..33f9b5c 100644
--- a/api/api.go
+++ b/api/api.go
@@ -2,6 +2,7 @@ package api
 
 import (
 	"bufio"
+	"bytes"
 	"context"
 	"encoding/base64"
 	"encoding/xml"
@@ -400,13 +401,21 @@ func shouldDecodeAWSChunkedPayload(r *http.Request) bool {
 		return true
 	}
 	signingMode := strings.ToLower(r.Header.Get("x-amz-content-sha256"))
-	return strings.HasPrefix(signingMode, "streaming-aws4-hmac-sha256-payload")
+	if strings.HasPrefix(signingMode, "streaming-aws4-hmac-sha256-payload") {
+		return true
+	}
+	return strings.HasPrefix(signingMode, "streaming-unsigned-payload")
 }
 
 func newAWSChunkedDecodingReader(src io.Reader) io.ReadCloser {
+	probedReader, isAWSChunked := probeAWSChunkedPayload(src)
+	if !isAWSChunked {
+		return io.NopCloser(probedReader)
+	}
+
 	pr, pw := io.Pipe()
 	go func() {
-		if err := decodeAWSChunkedPayload(src, pw); err != nil {
+		if err := decodeAWSChunkedPayload(probedReader, pw); err != nil {
 			_ = pw.CloseWithError(err)
 			return
 		}
@@ -415,6 +424,30 @@ func newAWSChunkedDecodingReader(src io.Reader) io.ReadCloser {
 	return pr
 }
 
+func probeAWSChunkedPayload(src io.Reader) (io.Reader, bool) {
+	reader := bufio.NewReaderSize(src, 512)
+	headerLine, err := reader.ReadSlice('\n')
+	replay := io.MultiReader(bytes.NewReader(headerLine), reader)
+	if err != nil {
+		return replay, false
+	}
+
+	line := strings.TrimRight(string(headerLine), "\r\n")
+	chunkSizeToken := line
+	if idx := strings.IndexByte(chunkSizeToken, ';'); idx >= 0 {
+		chunkSizeToken = chunkSizeToken[:idx]
+	}
+	chunkSizeToken = strings.TrimSpace(chunkSizeToken)
+	if chunkSizeToken == "" {
+		return replay, false
+	}
+	size, parseErr := strconv.ParseInt(chunkSizeToken, 16, 64)
+	if parseErr != nil || size < 0 {
+		return replay, false
+	}
+	return replay, true
+}
+
 func decodeAWSChunkedPayload(src io.Reader, dst io.Writer) error {
 	reader := bufio.NewReader(src)
 	for {
diff --git a/auth/sigv4.go b/auth/sigv4.go
index d79b628..8988498 100644
--- a/auth/sigv4.go
+++ b/auth/sigv4.go
@@ -259,7 +259,57 @@ func canonicalPath(u *url.URL) string {
 	if path == "" {
 		return "/"
 	}
-	return path
+	return awsEncodePath(path)
+}
+
+func awsEncodePath(path string) string {
+	var b strings.Builder
+	b.Grow(len(path))
+	for i := 0; i < len(path); i++ {
+		ch := path[i]
+		if ch == '/' || isUnreserved(ch) {
+			b.WriteByte(ch)
+			continue
+		}
+		if ch == '%' && i+2 < len(path) && isHex(path[i+1]) && isHex(path[i+2]) {
+			b.WriteByte('%')
+			b.WriteByte(toUpperHex(path[i+1]))
+			b.WriteByte(toUpperHex(path[i+2]))
+			i += 2
+			continue
+		}
+		b.WriteByte('%')
+		b.WriteByte(hexUpper(ch >> 4))
+		b.WriteByte(hexUpper(ch & 0x0F))
+	}
+	return b.String()
+}
+
+func isUnreserved(ch byte) bool {
+	return (ch >= 'A' && ch <= 'Z') ||
+		(ch >= 'a' && ch <= 'z') ||
+		(ch >= '0' && ch <= '9') ||
+		ch == '-' || ch == '_' || ch == '.' || ch == '~'
+}
+
+func isHex(ch byte) bool {
+	return (ch >= '0' && ch <= '9') ||
+		(ch >= 'a' && ch <= 'f') ||
+		(ch >= 'A' && ch <= 'F')
+}
+
+func toUpperHex(ch byte) byte {
+	if ch >= 'a' && ch <= 'f' {
+		return ch - ('a' - 'A')
+	}
+	return ch
+}
+
+func hexUpper(nibble byte) byte {
+	if nibble < 10 {
+		return '0' + nibble
+	}
+	return 'A' + (nibble - 10)
 }
 
 type queryPair struct {