Tweak request and response parsing

gemini.go

@@ -11,8 +11,6 @@ func init() {
 	mime.AddExtensionType(".gemini", "text/gemini")
 }
 
-var crlf = []byte("\r\n")
-
 // Errors.
 var (
 	ErrInvalidRequest  = errors.New("gemini: invalid request")
@@ -22,3 +20,15 @@ var (
 	// when the response status code does not permit a body.
 	ErrBodyNotAllowed = errors.New("gemini: response status code does not allow body")
 )
+
+var crlf = []byte("\r\n")
+
+func trimCRLF(b []byte) ([]byte, bool) {
+	// Check for CR
+	if len(b) < 2 || b[len(b)-2] != '\r' {
+		return nil, false
+	}
+	// Trim CRLF
+	b = b[:len(b)-2]
+	return b, true
+}

request.go

@@ -51,26 +51,25 @@ func NewRequest(rawurl string) (*Request, error) {
 // for specialized applications; most code should use the Server
 // to read requests and handle them via the Handler interface.
 func ReadRequest(r io.Reader) (*Request, error) {
-	// Read URL
+	// Limit request size
 	r = io.LimitReader(r, 1026)
 	br := bufio.NewReaderSize(r, 1026)
-	rawurl, err := br.ReadString('\r')
+	b, err := br.ReadBytes('\n')
 	if err != nil {
+		if err == io.EOF {
+			return nil, ErrInvalidRequest
+		}
 		return nil, err
 	}
-	// Read terminating line feed
-	if b, err := br.ReadByte(); err != nil {
-		return nil, err
-	} else if b != '\n' {
+	// Read URL
+	rawurl, ok := trimCRLF(b)
+	if !ok {
 		return nil, ErrInvalidRequest
 	}
-	// Trim carriage return
-	rawurl = rawurl[:len(rawurl)-1]
-	// Validate URL
-	if len(rawurl) > 1024 {
+	if len(rawurl) == 0 {
 		return nil, ErrInvalidRequest
 	}
-	u, err := url.Parse(rawurl)
+	u, err := url.Parse(string(rawurl))
 	if err != nil {
 		return nil, err
 	}

request_test.go

@@ -2,7 +2,6 @@ package gemini
 
 import (
 	"bufio"
-	"io"
 	"net/url"
 	"strings"
 	"testing"
@@ -36,25 +35,25 @@ func TestReadRequest(t *testing.T) {
 		},
 		{
 			Raw: "\r\n",
-			URL: &url.URL{},
+			Err: ErrInvalidRequest,
 		},
 		{
 			Raw: "gemini://example.com\n",
-			Err: io.EOF,
+			Err: ErrInvalidRequest,
 		},
 		{
 			Raw: "gemini://example.com",
-			Err: io.EOF,
+			Err: ErrInvalidRequest,
 		},
 		{
 			// 1030 bytes
 			Raw: maxURL + "xxxxxx",
-			Err: io.EOF,
+			Err: ErrInvalidRequest,
 		},
 		{
 			// 1027 bytes
 			Raw: maxURL + "x" + "\r\n",
-			Err: io.EOF,
+			Err: ErrInvalidRequest,
 		},
 		{
 			// 1024 bytes

response.go

@@ -46,43 +46,39 @@ func ReadResponse(r io.ReadCloser) (*Response, error) {
 	resp := &Response{}
 	br := bufio.NewReader(r)
 
-	// Read the status
-	statusB := make([]byte, 2)
-	if _, err := br.Read(statusB); err != nil {
+	// Read response header
+	b, err := br.ReadBytes('\n')
+	if err != nil {
+		if err == io.EOF {
+			return nil, ErrInvalidResponse
+		}
 		return nil, err
 	}
-	status, err := strconv.Atoi(string(statusB))
+	if len(b) < 3 {
+		return nil, ErrInvalidResponse
+	}
+
+	// Read the status
+	status, err := strconv.Atoi(string(b[:2]))
 	if err != nil {
 		return nil, ErrInvalidResponse
 	}
 	resp.Status = Status(status)
 
 	// Read one space
-	if b, err := br.ReadByte(); err != nil {
-		return nil, err
-	} else if b != ' ' {
+	if b[2] != ' ' {
 		return nil, ErrInvalidResponse
 	}
 
 	// Read the meta
-	meta, err := br.ReadString('\r')
-	if err != nil {
-		return nil, err
+	meta, ok := trimCRLF(b[3:])
+	if !ok {
+		return nil, ErrInvalidResponse
 	}
-	// Trim carriage return
-	meta = meta[:len(meta)-1]
-	// Ensure meta is less than or equal to 1024 bytes
 	if len(meta) == 0 || len(meta) > 1024 {
 		return nil, ErrInvalidResponse
 	}
-	resp.Meta = meta
-
-	// Read terminating newline
-	if b, err := br.ReadByte(); err != nil {
-		return nil, err
-	} else if b != '\n' {
-		return nil, ErrInvalidResponse
-	}
+	resp.Meta = string(meta)
 
 	if resp.Status.Class() == StatusSuccess {
 		resp.Body = newBufReadCloser(br, r)

response_test.go

@@ -65,15 +65,15 @@ func TestReadWriteResponse(t *testing.T) {
 		},
 		{
 			Raw: "",
-			Err: io.EOF,
+			Err: ErrInvalidResponse,
 		},
 		{
 			Raw: "10 Search query",
-			Err: io.EOF,
+			Err: ErrInvalidResponse,
 		},
 		{
 			Raw: "20 text/gemini\nHello, world!",
-			Err: io.EOF,
+			Err: ErrInvalidResponse,
 		},
 		{
 			Raw: "20 text/gemini\rHello, world!",
@@ -81,7 +81,7 @@ func TestReadWriteResponse(t *testing.T) {
 		},
 		{
 			Raw: "20 text/gemini\r",
-			Err: io.EOF,
+			Err: ErrInvalidResponse,
 		},
 		{
 			Raw: "abcdefghijklmnopqrstuvwxyz",