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|
{ config, pkgs, lib, ... }:
with lib;
{
config = {
services.postfix = {
enable = true;
hostname = "surtr.yggdrasil.li";
recipientDelimiter = "+";
setSendmail = true;
postmasterAlias = ""; rootAlias = ""; extraAliases = "";
destination = [];
sslCert = "/run/credentials/postfix.service/surtr.yggdrasil.li.pem";
sslKey = "/run/credentials/postfix.service/surtr.yggdrasil.li.key.pem";
networks = ["127.0.0.0/8" "[::ffff:127.0.0.0]/104" "[::1]/128" "10.141.0.0/16"];
config = let
relay_ccert = "texthash:${pkgs.writeText "relay_ccert" ""}";
in {
#the dh params
smtpd_tls_dh1024_param_file = toString config.security.dhparams.params."postfix-1024".path;
smtpd_tls_dh512_param_file = toString config.security.dhparams.params."postfix-512".path;
#enable ECDH
smtpd_tls_eecdh_grade = "strong";
#enabled SSL protocols, don't allow SSLv2 and SSLv3
smtpd_tls_protocols = ["!SSLv2" "!SSLv3" "!TLSv1" "!TLSv1.1" "!TLSv1.2"];
smtpd_tls_mandatory_protocols = ["!SSLv2" "!SSLv3" "!TLSv1" "!TLSv1.1" "!TLSv1.2"];
#allowed ciphers for smtpd_tls_security_level=encrypt
smtpd_tls_mandatory_ciphers = "high";
#allowed ciphers for smtpd_tls_security_level=may
#smtpd_tls_ciphers = high
#enforce the server cipher preference
tls_preempt_cipherlist = true;
#disable following ciphers for smtpd_tls_security_level=encrypt
smtpd_tls_mandatory_exclude_ciphers = ["aNULL" "MD5" "DES" "ADH" "RC4" "PSD" "SRP" "3DES" "eNULL"];
#disable following ciphers for smtpd_tls_security_level=may
smtpd_tls_exclude_ciphers = ["aNULL" "MD5" "DES" "ADH" "RC4" "PSD" "SRP" "3DES" "eNULL"];
#enable TLS logging to see the ciphers for inbound connections
smtpd_tls_loglevel = "1";
#enable TLS logging to see the ciphers for outbound connections
smtp_tls_loglevel = "1";
smtpd_tls_ask_ccert = true;
smtpd_tls_CAfile = toString ./ca/ca.crt;
smtp_tls_security_level = "dane";
smtp_dns_support_level = "dnssec";
tls_server_sni_maps = ''cidr:${pkgs.writeText "sni" ''
bouncy.email /run/credentials/postfix.service/bouncy.email.sni.pem
mailin.bouncy.email /run/credentials/postfix.service/mailin.bouncy.email.sni.pem
mailsub.bouncy.email /run/credentials/postfix.service/mailsub.bouncy.email.sni.pem
.bouncy.email /run/credentials/postfix.service/bouncy.email.sni.pem
''}'';
local_recipient_maps = "";
# 10 GiB
message_size_limit = "10737418240";
# 10 GiB
mailbox_size_limit = "10737418240";
smtpd_delay_reject = true;
smtpd_helo_required = true;
smtpd_helo_restrictions = "permit";
smtpd_recipient_restrictions = [
"reject_unauth_pipelining"
"reject_non_fqdn_recipient"
"reject_unknown_recipient_domain"
"permit_mynetworks"
"check_ccert_access ${relay_ccert}"
"reject_non_fqdn_helo_hostname"
"reject_invalid_helo_hostname"
"reject_unauth_destination"
"reject_unknown_recipient_domain"
"reject_unverified_recipient"
];
smtpd_relay_restrictions = [
"permit_mynetworks"
"check_ccert_access ${relay_ccert}"
"reject_unauth_destination"
];
propagate_unmatched_extensions = ["canonical" "virtual" "alias"];
smtpd_authorized_verp_clients = "$authorized_verp_clients";
authorized_verp_clients = "$mynetworks";
milter_default_action = "accept";
smtpd_milters = [config.services.opendkim.socket];
non_smtpd_milters = [config.services.opendkim.socket];
alias_maps = "";
queue_run_delay = "10s";
minimal_backoff_time = "1m";
maximal_backoff_time = "10m";
maximal_queue_lifetime = "100m";
bounce_queue_lifetime = "20m";
smtpd_discard_ehlo_keyword_address_maps = "cidr:${pkgs.writeText "esmtp_access" ''
# Allow DSN requests from local subnet only
192.168.0.0/16 silent-discard
172.16.0.0/12 silent-discard
10.0.0.0/8 silent-discard
0.0.0.0/0 silent-discard, dsn
fd00::/8 silent-discard
::/0 silent-discard, dsn
''}";
sender_canonical_maps = "tcp:localhost:${toString config.services.postsrsd.forwardPort}";
sender_canonical_classes = "envelope_sender";
recipient_canonical_maps = "tcp:localhost:${toString config.services.postsrsd.reversePort}";
recipient_canonical_classes = ["envelope_recipient" "header_recipient"];
};
masterConfig = {
smtps = {
type = "inet";
private = false;
command = "smtpd";
args = [
"-o" "smtpd_tls_wrappermode=yes"
"-o" "smtpd_tls_req_ccert=yes"
"-o" "smtpd_client_restrictions=permit_tls_all_clientcerts,reject"
"-o" "smtpd_recipient_restrictions=reject_unauth_pipelining,reject_non_fqdn_recipient,reject_unknown_recipient_domain,permit_tls_all_clientcerts,reject"
];
};
};
};
services.postsrsd = {
enable = true;
domain = "srs.surtr.yggdrasil.li";
separator = "+";
excludeDomains = [ "surtr.yggdrasil.li"
".bouncy.email" "bouncy.email"
];
};
services.opendkim = {
enable = true;
user = "postfix"; group = "postfix";
socket = "local:/run/opendkim/opendkim.sock";
domains = ''csl:${concatStringsSep "," ["surtr.yggdrasil.li" "bouncy.email"]}'';
selector = "surtr";
configFile = builtins.toFile "opendkim.conf" ''
Syslog true
MTACommand ${config.security.wrapperDir}/sendmail
LogResults true
SignatureAlgorithm ed25519-sha256
'';
};
security.dhparams = {
params = {
"postfix-512".bits = 512;
"postfix-1024".bits = 2048;
};
};
security.acme.domains = {
"bouncy.email" = {};
"mailin.bouncy.email" = {};
"mailsub.bouncy.email" = {};
"surtr.yggdrasil.li" = {};
};
systemd.services.postfix = {
preStart = concatMapStringsSep "\n" (domain: ''
(
umask 0037
cat /var/lib/acme/${domain}/key.pem /var/lib/acme/${domain}/full.pem > /var/lib/acme/${domain}/sni.pem
chown acme:acme /var/lib/acme/${domain}/sni.pem
)
'') ["bouncy.email" "mailin.bouncy.email" "mailsub.bouncy.email" "surtr.yggdrasil.li"];
serviceConfig.LoadCredential = [
"surtr.yggdrasil.li.key.pem:${config.security.acme.certs."surtr.yggdrasil.li".directory}/key.pem"
"surtr.yggdrasil.li.pem:${config.security.acme.certs."surtr.yggdrasil.li".directory}/fullchain.pem"
"bouncy.email.sni.pem:${config.security.acme.certs."bouncy.email".directory}/sni.pem"
"mailin.bouncy.email.sni.pem:${config.security.acme.certs."mailin.bouncy.email".directory}/sni.pem"
"mailsub.bouncy.email.sni.pem:${config.security.acme.certs."mailsub.bouncy.email".directory}/sni.pem"
];
};
};
}
|
