blob: 0a888e86aa8762b8a121f2b2b48d507047385d03 (
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
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
{ config, lib, pkgs, ... }:
with lib; let
cfg = config.local.mailHost;
imapHostname = config.local.domains.imap.main;
inherit (config.local) users virtual;
in
{
options.local.mailHost = {
enable = mkEnableOption "mailbox host service";
mdaListen = mkOption {
type = types.str;
};
saslPort = mkOption {
type = types.port;
};
lmtpPort = mkOption {
type = types.port;
};
};
config = mkIf cfg.enable {
services = {
dovecot2 =
let
cert = config.security.acme.certs.${imapHostname}.directory;
in
{
enable = true;
enablePAM = false;
enableLmtp = true;
sslServerKey = "${cert}/key.pem";
sslServerCert = "${cert}/fullchain.pem";
modules = [ pkgs.dovecot_pigeonhole ];
mailUser = "vmail";
mailGroup = "vmail";
mailLocation = "maildir:~/mail";
mailPlugins.perProtocol.lmtp.enable = [ "sieve" ];
extraConfig =
let
inherit (config.networking) domain;
# https://dovecot.org/list/dovecot/2019-March/115250.html
# Otra solución posible (https://serverfault.com/a/1062274/980378):
# auth_username_format = %{if;%d;eq;${domain};%Ln;%Lu}
localEntry = canonical: username: ''
${username}:::::::user=${canonical} nopassword userdb_user=${canonical}
'';
localMailboxes =
pkgs.writeText "local-mailboxes"
(concatStrings
(flatten (mapAttrsToList
(canonical: user:
map (localEntry canonical) ([ canonical ] ++ user.hardAliases))
users)));
localCerts =
flatten (mapAttrsToList
(canonical: user:
let
certNames = {
inherit canonical;
logins = [ canonical ] ++ user.hardAliases;
};
in
map (flip nameValuePair certNames) user.mail.certs)
users);
vmailCerts =
flatten (flatten (mapAttrsToList
(domain: virtual: mapAttrsToList
(username: user:
let
address = "${username}@${domain}";
certNames = {
canonical = address;
logins = [ address ];
};
in
map (flip nameValuePair certNames) user.mail.certs)
virtual.users)
virtual));
certLogins =
pkgs.writeText "cert-logins"
(concatStrings (flatten (mapAttrsToList
(uuid: names: map
(addr: ''
${uuid}.mail-client@nodomain,${addr}:::::::user=${names.canonical}
'')
names.logins)
(listToAttrs (localCerts ++ vmailCerts)))));
vmailPath = "/var/lib/vmail/%{if;%d;ne;;%Ld;${domain}}";
in
''
auth_mechanisms = plain login external
ssl_ca = <${config.local.pki.ca.mail.fullchain}
ssl_require_crl = yes
ssl_verify_client_cert = yes
# Esto descarta @domain.tld de locales explícitos, pero lo exige para los demás.
# Implicación: locales implícitos sin dominio fallan en autenticar
auth_username_format = %{if;%Ld;eq;${domain};%Ln;%{if;%d;ne;;%Lu;%Ln@nodomain}}
auth_ssl_username_from_cert = yes
# TODO: los defaults de nixpkgs dejan los sockets bajo
# /run/dovecot2 con demasiados permisos rwx, arreglar
service auth {
inet_listener mta-sasl {
port = ${toString cfg.saslPort}
address = ${cfg.mdaListen}
}
}
service lmtp {
inet_listener mta-lmtp {
port = ${toString cfg.lmtpPort}
address = ${cfg.mdaListen}
}
}
# FIXME: Esta cadena de passdbs hace que 'doveadm user lookup'
# falle para usuarios locales, pero todo lo demás sirve. Parece
# ser debido a que pam no puede enumerar.
passdb {
driver = static
args = nopassword
master = yes
mechanisms = external
result_success = continue-fail
result_failure = return-fail
result_internalfail = return-fail
}
passdb {
driver = passwd-file
args = scheme=PLAIN username_format=%{master_user},%Lu ${certLogins}
mechanisms = external
override_fields = nopassword
result_failure = return-fail
result_internalfail = return-fail
}
passdb {
driver = passwd-file
args = username_format=%Ln ${vmailPath}/passwd
}
passdb {
driver = passwd-file
args = scheme=PLAIN ${localMailboxes}
# Esta es una forma de determinar si se encontró el usuario en
# el passwd-file por medio de nopassword sin realmente
# autenticarlo. Cuidado con result_success, porque si eso se
# configura mal se permite inicio de sesión con cualquier
# contraseña (!!!).
result_success = continue
result_failure = return-fail
result_internalfail = return-fail
username_filter = !*@*
}
passdb {
driver = pam
args = dovecot2
username_filter = !*@*
#TODO: algo como 'override_fields = allow_nets=...'
}
userdb {
driver = passwd-file
args = username_format=%Ln ${vmailPath}/passwd
override_fields = uid=vmail gid=vmail home=${vmailPath}/home/%Ln
}
userdb {
driver = passwd-file
args = ${localMailboxes}
result_success = continue-ok
result_internalfail = return-fail
skip = found
}
userdb {
driver = passwd
args = blocking=no
skip = notfound
}
'';
};
fail2ban.jails.dovecot.settings = {
filter = "dovecot[mode=aggressive]";
maxretry = 3;
};
};
security = {
# Necesario debido a 'enablePAM = false'
pam.services.dovecot2 = { };
acme.certs.${imapHostname} = {
inherit (config.services.dovecot2) group;
};
};
users = {
users.${config.services.dovecot2.mailUser}.uid = 995;
groups.${config.services.dovecot2.mailGroup}.gid = 993;
};
networking.firewall.allowedTCPPorts = [ 143 993 ];
local.certs.imap.enable = true;
};
}
|
