http: check explicit wrong Request.ContentLength values

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5070041

diff --git a/src/pkg/http/requestwrite_test.go b/src/pkg/http/requestwrite_test.go
index 458f0bd7f4b731f18c54507e266e14872c463773..128ef776b8abaf427a1ef85194992fd96e5cf6f8 100644 (file)
--- a/src/pkg/http/requestwrite_test.go
+++ b/src/pkg/http/requestwrite_test.go
@@ -16,10 +16,11 @@ import (
 )
 
 type reqWriteTest struct {
-       Req      Request
-       Body     interface{} // optional []byte or func() io.ReadCloser to populate Req.Body
-       Raw      string
-       RawProxy string
+       Req       Request
+       Body      interface{} // optional []byte or func() io.ReadCloser to populate Req.Body
+       Raw       string
+       RawProxy  string
+       WantError os.Error
 }
 
 var reqWriteTests = []reqWriteTest{
@@ -78,6 +79,8 @@ var reqWriteTests = []reqWriteTest{
                        "Accept-Language: en-us,en;q=0.5\r\n" +
                        "Keep-Alive: 300\r\n" +
                        "Proxy-Connection: keep-alive\r\n\r\n",
+
+               nil,
        },
        // HTTP/1.1 => chunked coding; body; empty trailer
        {
@@ -107,6 +110,8 @@ var reqWriteTests = []reqWriteTest{
                        "User-Agent: Go http package\r\n" +
                        "Transfer-Encoding: chunked\r\n\r\n" +
                        chunk("abcdef") + chunk(""),
+
+               nil,
        },
        // HTTP/1.1 POST => chunked coding; body; empty trailer
        {
@@ -139,6 +144,8 @@ var reqWriteTests = []reqWriteTest{
                        "Connection: close\r\n" +
                        "Transfer-Encoding: chunked\r\n\r\n" +
                        chunk("abcdef") + chunk(""),
+
+               nil,
        },
 
        // HTTP/1.1 POST with Content-Length, no chunking
@@ -174,6 +181,8 @@ var reqWriteTests = []reqWriteTest{
                        "Content-Length: 6\r\n" +
                        "\r\n" +
                        "abcdef",
+
+               nil,
        },
 
        // HTTP/1.1 POST with Content-Length in headers
@@ -203,6 +212,8 @@ var reqWriteTests = []reqWriteTest{
                        "Content-Length: 6\r\n" +
                        "\r\n" +
                        "abcdef",
+
+               nil,
        },
 
        // default to HTTP/1.1
@@ -225,6 +236,8 @@ var reqWriteTests = []reqWriteTest{
                        "Host: www.google.com\r\n" +
                        "User-Agent: Go http package\r\n" +
                        "\r\n",
+
+               nil,
        },
 
        // Request with a 0 ContentLength and a 0 byte body.
@@ -249,6 +262,8 @@ var reqWriteTests = []reqWriteTest{
                        "Host: example.com\r\n" +
                        "User-Agent: Go http package\r\n" +
                        "\r\n",
+
+               nil,
        },
 
        // Request with a 0 ContentLength and a 1 byte body.
@@ -275,6 +290,74 @@ var reqWriteTests = []reqWriteTest{
                        "User-Agent: Go http package\r\n" +
                        "Transfer-Encoding: chunked\r\n\r\n" +
                        chunk("x") + chunk(""),
+
+               nil,
+       },
+
+       // Request with a ContentLength of 10 but a 5 byte body.
+       {
+               Request{
+                       Method:        "POST",
+                       RawURL:        "/",
+                       Host:          "example.com",
+                       ProtoMajor:    1,
+                       ProtoMinor:    1,
+                       ContentLength: 10, // but we're going to send only 5 bytes
+               },
+
+               []byte("12345"),
+
+               "", // ignored
+               "", // ignored
+
+               os.NewError("http: Request.ContentLength=10 with Body length 5"),
+       },
+
+       // Request with a ContentLength of 4 but an 8 byte body.
+       {
+               Request{
+                       Method:        "POST",
+                       RawURL:        "/",
+                       Host:          "example.com",
+                       ProtoMajor:    1,
+                       ProtoMinor:    1,
+                       ContentLength: 4, // but we're going to try to send 8 bytes
+               },
+
+               []byte("12345678"),
+
+               "", // ignored
+               "", // ignored
+
+               os.NewError("http: Request.ContentLength=4 with Body length 8"),
+       },
+
+       // Request with a 5 ContentLength and nil body.
+       {
+               Request{
+                       Method:        "POST",
+                       RawURL:        "/",
+                       Host:          "example.com",
+                       ProtoMajor:    1,
+                       ProtoMinor:    1,
+                       ContentLength: 5, // but we'll omit the body
+               },
+
+               nil, // missing body
+
+               "POST / HTTP/1.1\r\n" +
+                       "Host: example.com\r\n" +
+                       "User-Agent: Go http package\r\n" +
+                       "Content-Length: 5\r\n\r\n" +
+                       "",
+
+               "POST / HTTP/1.1\r\n" +
+                       "Host: example.com\r\n" +
+                       "User-Agent: Go http package\r\n" +
+                       "Content-Length: 5\r\n\r\n" +
+                       "",
+
+               os.NewError("http: Request.ContentLength=5 with nil Body"),
        },
 }
 
@@ -298,10 +381,14 @@ func TestRequestWrite(t *testing.T) {
                }
                var braw bytes.Buffer
                err := tt.Req.Write(&braw)
+               if g, e := fmt.Sprintf("%v", err), fmt.Sprintf("%v", tt.WantError); g != e {
+                       t.Errorf("writing #%d, err = %q, want %q", i, g, e)
+                       continue
+               }
                if err != nil {
-                       t.Errorf("error writing #%d: %s", i, err)
                        continue
                }
+
                sraw := braw.String()
                if sraw != tt.Raw {
                        t.Errorf("Test %d, expecting:\n%s\nGot:\n%s\n", i, tt.Raw, sraw)

diff --git a/src/pkg/http/transfer.go b/src/pkg/http/transfer.go
index 0a754d20a33b29589cb3d358055077f3f83ee207..8b12447acc924e3e2b9a3313baf83bed88ebd380 100644 (file)
--- a/src/pkg/http/transfer.go
+++ b/src/pkg/http/transfer.go
@@ -7,6 +7,7 @@ package http
 import (
        "bytes"
        "bufio"
+       "fmt"
        "io"
        "io/ioutil"
        "os"
@@ -21,7 +22,7 @@ type transferWriter struct {
        Body             io.Reader
        BodyCloser       io.Closer
        ResponseToHEAD   bool
-       ContentLength    int64
+       ContentLength    int64 // -1 means unknown, 0 means exactly none
        Close            bool
        TransferEncoding []string
        Trailer          Header
@@ -34,6 +35,10 @@ func newTransferWriter(r interface{}) (t *transferWriter, err os.Error) {
        atLeastHTTP11 := false
        switch rr := r.(type) {
        case *Request:
+               if rr.ContentLength != 0 && rr.Body == nil {
+                       return nil, fmt.Errorf("http: Request.ContentLength=%d with nil Body", rr.ContentLength)
+               }
+
                t.Body = rr.Body
                t.BodyCloser = rr.Body
                t.ContentLength = rr.ContentLength
@@ -154,6 +159,8 @@ func (t *transferWriter) WriteHeader(w io.Writer) (err os.Error) {
 }
 
 func (t *transferWriter) WriteBody(w io.Writer) (err os.Error) {
+       var ncopy int64
+
        // Write body
        if t.Body != nil {
                if chunked(t.TransferEncoding) {
@@ -163,9 +170,14 @@ func (t *transferWriter) WriteBody(w io.Writer) (err os.Error) {
                                err = cw.Close()
                        }
                } else if t.ContentLength == -1 {
-                       _, err = io.Copy(w, t.Body)
+                       ncopy, err = io.Copy(w, t.Body)
                } else {
-                       _, err = io.Copy(w, io.LimitReader(t.Body, t.ContentLength))
+                       ncopy, err = io.Copy(w, io.LimitReader(t.Body, t.ContentLength))
+                       nextra, err := io.Copy(ioutil.Discard, t.Body)
+                       if err != nil {
+                               return err
+                       }
+                       ncopy += nextra
                }
                if err != nil {
                        return err
@@ -175,6 +187,11 @@ func (t *transferWriter) WriteBody(w io.Writer) (err os.Error) {
                }
        }
 
+       if t.ContentLength != -1 && t.ContentLength != ncopy {
+               return fmt.Errorf("http: Request.ContentLength=%d with Body length %d",
+                       t.ContentLength, ncopy)
+       }
+
        // TODO(petar): Place trailer writer code here.
        if chunked(t.TransferEncoding) {
                // Last chunk, empty trailer