From 4cc92b5f712abe7b9522a48b701a7af90eaa134b Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Mon, 1 May 2017 17:01:09 +0200 Subject: Rename sig package --- file/file.go | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 file/file.go (limited to 'file/file.go') diff --git a/file/file.go b/file/file.go new file mode 100644 index 0000000..ed1a93b --- /dev/null +++ b/file/file.go @@ -0,0 +1,93 @@ +// Package sig implements signify file format +package file + +import ( + "bytes" + "encoding/base64" + "errors" + "fmt" + "io" + "io/ioutil" + "os" + "strings" +) + +var ErrComment = errors.New("expected untrusted comment") + +// Block represents a encoded signify key or signature +// +// The encoded form is: +// untrusted comment: comment +// base64-encoded key +// optional message +type Block struct { + Comment string + Bytes []byte + Message []byte +} + +const untrusted = "untrusted comment:" + +func Encode(w io.Writer, b *Block) error { + fmt.Fprintln(w, untrusted, b.Comment) + fmt.Fprintln(w, base64.StdEncoding.EncodeToString(b.Bytes)) + w.Write(b.Message) + return nil +} + +func EncodeToMemory(b *Block) []byte { + buf := new(bytes.Buffer) + Encode(buf, b) + return buf.Bytes() +} + +func Decode(data []byte) (*Block, error) { + r := bytes.NewBuffer(data) + comment, err := r.ReadString('\n') + if err != nil { + return nil, err + } + if !strings.HasPrefix(comment, untrusted) { + return nil, ErrComment + } + raw, err := r.ReadString('\n') + if err != nil { + return nil, err + } + b, err := base64.StdEncoding.DecodeString(raw) + if err != nil { + return nil, err + } + message, err := ioutil.ReadAll(r) + if err != nil { + return nil, err + } + return &Block{ + Comment: strings.TrimSpace(comment[len(untrusted):]), + Bytes: b, + Message: message, + }, nil +} + +func DecodeFile(fname string) (*Block, error) { + body, err := ioutil.ReadFile(fname) + if err != nil { + return nil, err + } + return Decode(body) +} + +const ( + SecMode os.FileMode = 0600 + PubMode os.FileMode = 0644 + SigMode os.FileMode = 0644 +) + +func EncodeFile(fname string, perm os.FileMode, b *Block) error { + fd, err := os.OpenFile(fname, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm) + if err != nil { + return err + } + defer fd.Close() + return Encode(fd, b) +} -- cgit v1.2.3