net/http: ignore Transfer-Encoding for HTTP/1.0 responses

Fixes #12785

Change-Id: Iae4383889298c6a78b1ba41bd2cda70b0758fcba
Reviewed-on: https://go-review.googlesource.com/15737
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/net/http/response_test.go b/src/net/http/response_test.go
index 421cf55f49173813c4ceedc5dd45d45696c26167..d1c5a61a12d8cda836239619dc3f84dea4655f9e 100644 (file)
--- a/src/net/http/response_test.go
+++ b/src/net/http/response_test.go
@@ -456,6 +456,55 @@ some body`,
 
                "",
        },
+
+       // Issue 12785: HTTP/1.0 response with bogus (to be ignored) Transfer-Encoding.
+       // Without a Content-Length.
+       {
+               "HTTP/1.0 200 OK\r\n" +
+                       "Transfer-Encoding: bogus\r\n" +
+                       "\r\n" +
+                       "Body here\n",
+
+               Response{
+                       Status:        "200 OK",
+                       StatusCode:    200,
+                       Proto:         "HTTP/1.0",
+                       ProtoMajor:    1,
+                       ProtoMinor:    0,
+                       Request:       dummyReq("GET"),
+                       Header:        Header{},
+                       Close:         true,
+                       ContentLength: -1,
+               },
+
+               "Body here\n",
+       },
+
+       // Issue 12785: HTTP/1.0 response with bogus (to be ignored) Transfer-Encoding.
+       // With a Content-Length.
+       {
+               "HTTP/1.0 200 OK\r\n" +
+                       "Transfer-Encoding: bogus\r\n" +
+                       "Content-Length: 10\r\n" +
+                       "\r\n" +
+                       "Body here\n",
+
+               Response{
+                       Status:     "200 OK",
+                       StatusCode: 200,
+                       Proto:      "HTTP/1.0",
+                       ProtoMajor: 1,
+                       ProtoMinor: 0,
+                       Request:    dummyReq("GET"),
+                       Header: Header{
+                               "Content-Length": {"10"},
+                       },
+                       Close:         true,
+                       ContentLength: 10,
+               },
+
+               "Body here\n",
+       },
 }
 
 func TestReadResponse(t *testing.T) {

diff --git a/src/net/http/transfer.go b/src/net/http/transfer.go
index a8736b28e16106b6640ec0ffdb1d2392e7e43552..38b6f67c42860cc5ab9768770d7b36e7db383a86 100644 (file)
--- a/src/net/http/transfer.go
+++ b/src/net/http/transfer.go
@@ -271,6 +271,10 @@ type transferReader struct {
        Trailer          Header
 }
 
+func (t *transferReader) protoAtLeast(m, n int) bool {
+       return t.ProtoMajor > m || (t.ProtoMajor == m && t.ProtoMinor >= n)
+}
+
 // bodyAllowedForStatus reports whether a given response status code
 // permits a body.  See RFC2616, section 4.4.
 func bodyAllowedForStatus(status int) bool {
@@ -337,7 +341,7 @@ func readTransfer(msg interface{}, r *bufio.Reader) (err error) {
        }
 
        // Transfer encoding, content length
-       t.TransferEncoding, err = fixTransferEncoding(isResponse, t.RequestMethod, t.Header)
+       err = t.fixTransferEncoding()
        if err != nil {
                return err
        }
@@ -424,13 +428,18 @@ func chunked(te []string) bool { return len(te) > 0 && te[0] == "chunked" }
 // Checks whether the encoding is explicitly "identity".
 func isIdentity(te []string) bool { return len(te) == 1 && te[0] == "identity" }
 
-// Sanitize transfer encoding
-func fixTransferEncoding(isResponse bool, requestMethod string, header Header) ([]string, error) {
-       raw, present := header["Transfer-Encoding"]
+// fixTransferEncoding sanitizes t.TransferEncoding, if needed.
+func (t *transferReader) fixTransferEncoding() error {
+       raw, present := t.Header["Transfer-Encoding"]
        if !present {
-               return nil, nil
+               return nil
+       }
+       delete(t.Header, "Transfer-Encoding")
+
+       // Issue 12785; ignore Transfer-Encoding on HTTP/1.0 requests.
+       if !t.protoAtLeast(1, 1) {
+               return nil
        }
-       delete(header, "Transfer-Encoding")
 
        encodings := strings.Split(raw[0], ",")
        te := make([]string, 0, len(encodings))
@@ -445,13 +454,13 @@ func fixTransferEncoding(isResponse bool, requestMethod string, header Header) (
                        break
                }
                if encoding != "chunked" {
-                       return nil, &badStringError{"unsupported transfer encoding", encoding}
+                       return &badStringError{"unsupported transfer encoding", encoding}
                }
                te = te[0 : len(te)+1]
                te[len(te)-1] = encoding
        }
        if len(te) > 1 {
-               return nil, &badStringError{"too many transfer encodings", strings.Join(te, ",")}
+               return &badStringError{"too many transfer encodings", strings.Join(te, ",")}
        }
        if len(te) > 0 {
                // RFC 7230 3.3.2 says "A sender MUST NOT send a
@@ -470,11 +479,12 @@ func fixTransferEncoding(isResponse bool, requestMethod string, header Header) (
                // such a message downstream."
                //
                // Reportedly, these appear in the wild.
-               delete(header, "Content-Length")
-               return te, nil
+               delete(t.Header, "Content-Length")
+               t.TransferEncoding = te
+               return nil
        }
 
-       return nil, nil
+       return nil
 }
 
 // Determine the expected body length, using RFC 2616 Section 4.4. This