aboutsummaryrefslogtreecommitdiff
path: root/cmd_sign.go
blob: 91b58ea22a4f445fd6c6db98d2d8b798fc075212 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
package main

import (
	"context"
	"flag"
	"io/ioutil"
	"log"

	"dim13.org/signify/ask"
	"dim13.org/signify/b64file"
	"dim13.org/signify/key"
	"dim13.org/signify/zsig"
	"github.com/google/subcommands"
)

// Usage: signify -S [-ez] [-x sigfile] -s seckey -m message

type signCommand struct {
	embedded bool
	zip      bool
	sigFile  string
	secFile  string
	msgFile  string
}

func (s *signCommand) Name() string     { return "sign" }
func (s *signCommand) Synopsis() string { return "sign file" }
func (s *signCommand) Usage() string {
	return "sign [-ez] [-x sigfile] -s seckey -m message\n"
}

func (s *signCommand) SetFlags(f *flag.FlagSet) {
	f.BoolVar(&s.embedded, "e", false, "embed the message")
	f.BoolVar(&s.zip, "z", false, "sign gzip archive") // TODO
	f.StringVar(&s.sigFile, "x", "", "signature file")
	f.StringVar(&s.secFile, "s", "", "secret file (required)")
	f.StringVar(&s.msgFile, "m", "", "message file (required)")
}

func (s *signCommand) Execute(ctx context.Context, f *flag.FlagSet, args ...interface{}) subcommands.ExitStatus {
	if s.secFile == "" || s.msgFile == "" {
		f.Usage()
		return subcommands.ExitUsageError
	}
	if s.sigFile == "" {
		s.sigFile = SigName(s.msgFile)
	}

	switch {
	case s.zip && s.embedded:
		return subcommands.ExitUsageError
	case s.zip:
		if err := signGzip(s.secFile, s.msgFile, s.sigFile); err != nil {
			log.Println(err)
			return subcommands.ExitFailure
		}
	case s.embedded:
		if err := signEmbedded(s.secFile, s.msgFile, s.sigFile); err != nil {
			log.Println(err)
			return subcommands.ExitFailure
		}
	default:
		if err := signPlain(s.secFile, s.msgFile, s.sigFile); err != nil {
			log.Println(err)
			return subcommands.ExitFailure
		}
	}

	return subcommands.ExitSuccess
}

func signPlain(secFile, msgFile, sigFile string) error {
	sec, err := openSec(secFile)
	if err != nil {
		return err
	}
	msg, err := ioutil.ReadFile(msgFile)
	if err != nil {
		return err
	}
	sig := sec.Sign(msg)
	comment := VerifyWith(secFile)
	fd, err := Create(sigFile, ModeSig)
	if err != nil {
		return err
	}
	defer fd.Close()
	return b64file.Encode(fd, sig, comment, nil)
}

func signEmbedded(secFile, msgFile, sigFile string) error {
	sec, err := openSec(secFile)
	if err != nil {
		return err
	}
	msg, err := ioutil.ReadFile(msgFile)
	if err != nil {
		return err
	}
	sig := sec.Sign(msg)
	comment := VerifyWith(secFile)
	fd, err := Create(sigFile, ModeSig)
	if err != nil {
		return err
	}
	fd.Close()
	return b64file.Encode(fd, sig, comment, msg)
}

// TODO
func signGzip(secFile, msgFile, sigFile string) error {
	fd, err := Open(msgFile)
	if err != nil {
		return err
	}
	defer fd.Close()
	z, err := zsig.NewReader(fd)
	if err != nil {
		return err
	}
	log.Println(z)
	zhead, err := zsig.NewHeader(z)
	if err != nil {
		return err
	}
	log.Println(zhead)
	body, err := zhead.MarshalText()
	if err != nil {
		return err
	}
	log.Println(body)
	return nil
}

func openSec(fname string) (*key.Sec, error) {
	sec := new(key.Sec)
	fd, err := Open(fname)
	if err != nil {
		return nil, err
	}
	defer fd.Close()
	if _, _, err := b64file.Decode(fd, sec); err != nil {
		return nil, err
	}
	if err := sec.Crypt(ask.Passphrase{}); err != nil {
		return nil, err
	}
	if err := sec.Validate(); err != nil {
		return nil, err
	}
	return sec, nil
}