aboutsummaryrefslogtreecommitdiff
path: root/worker/imap/worker.go
blob: 51cb221cb73da87e2221730ad301845e893b953e (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
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
package imap

import (
	"crypto/tls"
	"crypto/x509"
	"fmt"
	"net/url"
	"strings"

	"github.com/emersion/go-imap"
	"github.com/emersion/go-imap-idle"
	"github.com/emersion/go-imap/client"

	"git.sr.ht/~sircmpwn/aerc2/worker/types"
)

var errUnsupported = fmt.Errorf("unsupported command")

type imapClient struct {
	*client.Client
	*idle.IdleClient
}

type IMAPWorker struct {
	config struct {
		scheme   string
		insecure bool
		addr     string
		user     *url.Userinfo
	}

	client   *imapClient
	selected imap.MailboxStatus
	updates  chan client.Update
	worker   *types.Worker
}

func NewIMAPWorker(worker *types.Worker) *IMAPWorker {
	return &IMAPWorker{
		worker:  worker,
		updates: make(chan client.Update, 50),
	}
}

func (w *IMAPWorker) verifyPeerCert(msg types.WorkerMessage) func(
	rawCerts [][]byte, _ [][]*x509.Certificate) error {

	return func(rawCerts [][]byte, _ [][]*x509.Certificate) error {
		pool := x509.NewCertPool()
		for _, rawCert := range rawCerts {
			cert, err := x509.ParseCertificate(rawCert)
			if err != nil {
				return err
			}
			pool.AddCert(cert)
		}

		request := &types.CertificateApprovalRequest{
			Message:  types.RespondTo(msg),
			CertPool: pool,
		}
		w.worker.PostMessage(request, nil)

		response := <-w.worker.Actions
		if response.InResponseTo() != request {
			return fmt.Errorf("Expected UI to respond to cert request")
		}
		if approval, ok := response.(*types.ApproveCertificate); !ok {
			return fmt.Errorf("Expected UI to send certificate approval")
		} else {
			if approval.Approved {
				return nil
			} else {
				return fmt.Errorf("UI rejected certificate")
			}
		}
	}
}

func (w *IMAPWorker) handleMessage(msg types.WorkerMessage) error {
	switch msg := msg.(type) {
	case *types.Unsupported:
		// No-op
	case *types.Configure:
		u, err := url.Parse(msg.Config.Source)
		if err != nil {
			return err
		}

		w.config.scheme = u.Scheme
		if strings.HasSuffix(w.config.scheme, "+insecure") {
			w.config.scheme = strings.TrimSuffix(w.config.scheme, "+insecure")
			w.config.insecure = true
		}

		w.config.addr = u.Host
		if !strings.ContainsRune(w.config.addr, ':') {
			w.config.addr += ":" + u.Scheme
		}

		w.config.scheme = u.Scheme
		w.config.user = u.User
	case *types.Connect:
		var (
			c   *client.Client
			err error
		)
		tlsConfig := &tls.Config{
			InsecureSkipVerify:    true,
			VerifyPeerCertificate: w.verifyPeerCert(msg),
		}
		switch w.config.scheme {
		case "imap":
			c, err = client.Dial(w.config.addr)
			if err != nil {
				return err
			}

			if !w.config.insecure {
				if err := c.StartTLS(tlsConfig); err != nil {
					return err
				}
			}
		case "imaps":
			c, err = client.DialTLS(w.config.addr, tlsConfig)
			if err != nil {
				return err
			}
		default:
			return fmt.Errorf("Unknown IMAP scheme %s", w.config.scheme)
		}

		if w.config.user != nil {
			username := w.config.user.Username()
			password, hasPassword := w.config.user.Password()
			if !hasPassword {
				// TODO: ask password
			}
			if err := c.Login(username, password); err != nil {
				return err
			}
		}

		if _, err := c.Select(imap.InboxName, false); err != nil {
			return err
		}

		c.Updates = w.updates
		w.client = &imapClient{c, idle.NewClient(c)}
		w.worker.PostMessage(&types.Done{types.RespondTo(msg)}, nil)
	case *types.ListDirectories:
		w.handleListDirectories(msg)
	case *types.OpenDirectory:
		w.handleOpenDirectory(msg)
	case *types.FetchDirectoryContents:
		w.handleFetchDirectoryContents(msg)
	default:
		return errUnsupported
	}
	return nil
}

func (w *IMAPWorker) handleImapUpdate(update client.Update) {
	w.worker.Logger.Printf("(= %T", update)
	switch update := update.(type) {
	case *client.MailboxUpdate:
		status := update.Mailbox
		if w.selected.Name == status.Name {
			w.selected = *status
		}
		w.worker.PostMessage(&types.DirectoryInfo{
			Flags:    status.Flags,
			Name:     status.Name,
			ReadOnly: status.ReadOnly,

			Exists: int(status.Messages),
			Recent: int(status.Recent),
			Unseen: int(status.Unseen),
		}, nil)
	}
}

func (w *IMAPWorker) Run() {
	for {
		select {
		case msg := <-w.worker.Actions:
			msg = w.worker.ProcessAction(msg)
			if err := w.handleMessage(msg); err == errUnsupported {
				w.worker.PostMessage(&types.Unsupported{
					Message: types.RespondTo(msg),
				}, nil)
			} else if err != nil {
				w.worker.PostMessage(&types.Error{
					Message: types.RespondTo(msg),
					Error:   err,
				}, nil)
			}
		case update := <-w.updates:
			w.handleImapUpdate(update)
		}
	}
}