From e1875336041ead704df7f481f8691452ef939556 Mon Sep 17 00:00:00 2001 From: Ayman Bagabas Date: Fri, 17 Nov 2023 15:27:49 -0500 Subject: plumbing: add git-proto-request type This the request used for the git transport protocol feat: nil writer --- plumbing/protocol/packp/common.go | 5 ++ plumbing/protocol/packp/gitproto.go | 115 ++++++++++++++++++++++++++++++++++++ 2 files changed, 120 insertions(+) create mode 100644 plumbing/protocol/packp/gitproto.go (limited to 'plumbing/protocol/packp') diff --git a/plumbing/protocol/packp/common.go b/plumbing/protocol/packp/common.go index fef50a4..a858323 100644 --- a/plumbing/protocol/packp/common.go +++ b/plumbing/protocol/packp/common.go @@ -48,6 +48,11 @@ func isFlush(payload []byte) bool { return len(payload) == 0 } +var ( + // ErrNilWriter is returned when a nil writer is passed to the encoder. + ErrNilWriter = fmt.Errorf("nil writer") +) + // ErrUnexpectedData represents an unexpected data decoding a message type ErrUnexpectedData struct { Msg string diff --git a/plumbing/protocol/packp/gitproto.go b/plumbing/protocol/packp/gitproto.go new file mode 100644 index 0000000..806e44c --- /dev/null +++ b/plumbing/protocol/packp/gitproto.go @@ -0,0 +1,115 @@ +package packp + +import ( + "fmt" + "io" + "strings" + + "github.com/go-git/go-git/v5/plumbing/format/pktline" +) + +var ( + // ErrInvalidGitProtoRequest is returned by Decode if the input is not a + // valid git protocol request. + ErrInvalidGitProtoRequest = fmt.Errorf("invalid git protocol request") +) + +// GitProtoRequest is a command request for the git protocol. +// It is used to send the command, endpoint, and extra parameters to the +// remote. +// See https://git-scm.com/docs/pack-protocol#_git_transport +type GitProtoRequest struct { + RequestCommand string + Pathname string + + // Optional + Host string + + // Optional + ExtraParams []string +} + +// validate validates the request. +func (g *GitProtoRequest) validate() error { + if g.RequestCommand == "" { + return fmt.Errorf("%w: empty request command", ErrInvalidGitProtoRequest) + } + + if g.Pathname == "" { + return fmt.Errorf("%w: empty pathname", ErrInvalidGitProtoRequest) + } + + return nil +} + +// Encode encodes the request into the writer. +func (g *GitProtoRequest) Encode(w io.Writer) error { + if w == nil { + return ErrNilWriter + } + + if err := g.validate(); err != nil { + return err + } + + p := pktline.NewEncoder(w) + req := fmt.Sprintf("%s %s\x00", g.RequestCommand, g.Pathname) + if host := g.Host; host != "" { + req += fmt.Sprintf("host=%s\x00", host) + } + + if len(g.ExtraParams) > 0 { + req += "\x00" + for _, param := range g.ExtraParams { + req += param + "\x00" + } + } + + if err := p.Encode([]byte(req)); err != nil { + return err + } + + return nil +} + +// Decode decodes the request from the reader. +func (g *GitProtoRequest) Decode(r io.Reader) error { + s := pktline.NewScanner(r) + if !s.Scan() { + return s.Err() + } + + line := string(s.Bytes()) + if len(line) == 0 { + return io.EOF + } + + if line[len(line)-1] != 0 { + return fmt.Errorf("%w: missing null terminator", ErrInvalidGitProtoRequest) + } + + parts := strings.SplitN(line, " ", 2) + if len(parts) != 2 { + return fmt.Errorf("%w: short request", ErrInvalidGitProtoRequest) + } + + g.RequestCommand = parts[0] + params := strings.Split(parts[1], string(null)) + if len(params) < 1 { + return fmt.Errorf("%w: missing pathname", ErrInvalidGitProtoRequest) + } + + if len(params) > 1 { + g.Host = params[1] + } + + if len(params) > 2 { + for _, param := range params[2:] { + if param != "" { + g.ExtraParams = append(g.ExtraParams, param) + } + } + } + + return nil +} -- cgit From f46d04a18759071e45b057908050a01e061f1ddd Mon Sep 17 00:00:00 2001 From: Ayman Bagabas Date: Fri, 17 Nov 2023 15:29:33 -0500 Subject: plumbing: transport: use git-proto-request and decode error-line errors --- plumbing/protocol/packp/gitproto.go | 9 ++- plumbing/protocol/packp/gitproto_test.go | 99 ++++++++++++++++++++++++++++++++ 2 files changed, 106 insertions(+), 2 deletions(-) create mode 100644 plumbing/protocol/packp/gitproto_test.go (limited to 'plumbing/protocol/packp') diff --git a/plumbing/protocol/packp/gitproto.go b/plumbing/protocol/packp/gitproto.go index 806e44c..0b7ff8f 100644 --- a/plumbing/protocol/packp/gitproto.go +++ b/plumbing/protocol/packp/gitproto.go @@ -76,7 +76,11 @@ func (g *GitProtoRequest) Encode(w io.Writer) error { func (g *GitProtoRequest) Decode(r io.Reader) error { s := pktline.NewScanner(r) if !s.Scan() { - return s.Err() + err := s.Err() + if err == nil { + return ErrInvalidGitProtoRequest + } + return err } line := string(s.Bytes()) @@ -99,8 +103,9 @@ func (g *GitProtoRequest) Decode(r io.Reader) error { return fmt.Errorf("%w: missing pathname", ErrInvalidGitProtoRequest) } + g.Pathname = params[0] if len(params) > 1 { - g.Host = params[1] + g.Host = strings.TrimPrefix(params[1], "host=") } if len(params) > 2 { diff --git a/plumbing/protocol/packp/gitproto_test.go b/plumbing/protocol/packp/gitproto_test.go new file mode 100644 index 0000000..9cf1049 --- /dev/null +++ b/plumbing/protocol/packp/gitproto_test.go @@ -0,0 +1,99 @@ +package packp + +import ( + "bytes" + "testing" +) + +func TestEncodeEmptyGitProtoRequest(t *testing.T) { + var buf bytes.Buffer + var p GitProtoRequest + err := p.Encode(&buf) + if err == nil { + t.Fatal("expected error") + } +} + +func TestEncodeGitProtoRequest(t *testing.T) { + var buf bytes.Buffer + p := GitProtoRequest{ + RequestCommand: "command", + Pathname: "pathname", + Host: "host", + ExtraParams: []string{"param1", "param2"}, + } + err := p.Encode(&buf) + if err != nil { + t.Fatal(err) + } + expected := "002ecommand pathname\x00host=host\x00\x00param1\x00param2\x00" + if buf.String() != expected { + t.Fatalf("expected %q, got %q", expected, buf.String()) + } +} + +func TestEncodeInvalidGitProtoRequest(t *testing.T) { + var buf bytes.Buffer + p := GitProtoRequest{ + RequestCommand: "command", + } + err := p.Encode(&buf) + if err == nil { + t.Fatal("expected error") + } +} + +func TestDecodeEmptyGitProtoRequest(t *testing.T) { + var buf bytes.Buffer + var p GitProtoRequest + err := p.Decode(&buf) + if err == nil { + t.Fatal("expected error") + } +} + +func TestDecodeGitProtoRequest(t *testing.T) { + var buf bytes.Buffer + buf.WriteString("002ecommand pathname\x00host=host\x00\x00param1\x00param2\x00") + var p GitProtoRequest + err := p.Decode(&buf) + if err != nil { + t.Fatal(err) + } + expected := GitProtoRequest{ + RequestCommand: "command", + Pathname: "pathname", + Host: "host", + ExtraParams: []string{"param1", "param2"}, + } + if p.RequestCommand != expected.RequestCommand { + t.Fatalf("expected %q, got %q", expected.RequestCommand, p.RequestCommand) + } + if p.Pathname != expected.Pathname { + t.Fatalf("expected %q, got %q", expected.Pathname, p.Pathname) + } + if p.Host != expected.Host { + t.Fatalf("expected %q, got %q", expected.Host, p.Host) + } + if len(p.ExtraParams) != len(expected.ExtraParams) { + t.Fatalf("expected %d, got %d", len(expected.ExtraParams), len(p.ExtraParams)) + } +} + +func TestDecodeInvalidGitProtoRequest(t *testing.T) { + var buf bytes.Buffer + buf.WriteString("0026command \x00host=host\x00\x00param1\x00param2") + var p GitProtoRequest + err := p.Decode(&buf) + if err == nil { + t.Fatal("expected error") + } +} + +func TestValidateEmptyGitProtoRequest(t *testing.T) { + var p GitProtoRequest + err := p.validate() + if err == nil { + t.Fatal("expected error") + } +} -- cgit