X-Git-Url: https://git.distorted.org.uk/~mdw/exim-config/blobdiff_plain/6aae076feb9b8fc05099dc68fc00100472004701..e90159689acef685dd341342f4697774a51c6a64:/base.m4 diff --git a/base.m4 b/base.m4 index 8211506..cb0f7a6 100644 --- a/base.m4 +++ b/base.m4 @@ -26,6 +26,7 @@ SECTION(global, priv)m4_dnl admin_groups = CONF_admin_groups +trusted_groups = CONF_trusted_groups prod_requires_admin = false SECTION(global, logging)m4_dnl @@ -39,7 +40,7 @@ syslog_timestamp = false SECTION(global, daemon)m4_dnl local_interfaces = <; CONF_interfaces -extra_local_interfaces = <; 0.0.0.0 ; :: +extra_local_interfaces = <; 0.0.0.0 ; ::0 SECTION(global, resource)m4_dnl deliver_queue_load_max = 8 @@ -80,16 +81,22 @@ SECTION(global, smtp)m4_dnl smtp_return_error_details = true accept_8bitmime = true +SECTION(global, env)m4_dnl +keep_environment = + SECTION(global, process)m4_dnl extract_addresses_remove_arguments = false headers_charset = utf-8 qualify_domain = CONF_master_domain +untrusted_set_sender = * +local_from_check = false +local_sender_retain = true SECTION(global, bounce)m4_dnl delay_warning = 1h : 24h : 2d SECTION(global, tls)m4_dnl -tls_certificate = CONF_sysconf_dir/server.cert +tls_certificate = CONF_sysconf_dir/server.certlist tls_privatekey = CONF_sysconf_dir/server.key tls_advertise_hosts = ${if exists {CONF_sysconf_dir/server.key} {*}{}} tls_dhparam = CONF_ca_dir/dh-param-2048.pem @@ -128,7 +135,7 @@ helo: {CONF_sysconf_dir/helo.conf} \ {${if match_ip \ {$sender_host_address} \ - {$value}}}}}} + {<; $value}}}}}} !verify = helo set acl_c_helo_warning = true @@ -140,6 +147,7 @@ SECTION(acl, misc)m4_dnl not_smtp_start: ## Record the user's name. warn set acl_c_user = $sender_ident + set acl_m_user = $sender_ident ## Done. accept @@ -150,26 +158,28 @@ SECTION(acl, mail)m4_dnl mail: ## If we stashed a warning header about HELO from earlier, we should - ## add it now. + ## add it now. Only don't bother if the client has authenticated + ## successfully for submission (because we can't expect mobile + ## clients to be properly set up knowing their names), or it's one of + ## our own satellites (because they're either properly set up anyway, + ## or satellites using us as a smarthost). warn condition = $acl_c_helo_warning - add_header = :after_received:X-Distorted-Warning: \ - BADHELO \ - Client's HELO doesn't match its IP address.\n\t\ - helo-name=$sender_helo_name \ - address=$sender_host_address + !condition = ${if eq{$acl_c_mode}{submission}} + !hosts = +allnets + WARNING_HEADER(BADHELO, + <:Client's HELO doesn't match its IP address.\n\t\ + helo-name=$sender_helo_name \ + address=$sender_host_address:>) ## Always allow the empty sender, so that we can receive bounces. accept senders = : - ## Ensure that the sender is routable. This is important to prevent - ## undeliverable bounces. - require message = Invalid sender; \ - ($sender_verify_failure; $acl_verify_message) - verify = sender + ## Ensure that the sender looks valid. + require acl = mail_check_sender ## If this is directly from a client then hack on it for a while. warn condition = ${if eq{$acl_c_mode}{submission}} - control = submission + control = submission/sender_retain ## Insist that a local client connect through TLS. deny message = Hosts within CONF_master_domain must use TLS @@ -184,6 +194,23 @@ SECTION(acl, mail-tail)m4_dnl ## And we're done. accept +SECTION(acl, misc)m4_dnl +mail_check_sender: + + ## See whether there's a special exception for this sender domain. + accept senders = ${LOOKUP_DOMAIN($sender_address_domain, + {KV(senders, {$value}{})}, + {})} + + ## Ensure that the sender is routable. This is important to prevent + ## undeliverable bounces. + require message = Invalid sender; \ + ($sender_verify_failure; $acl_verify_message) + verify = sender + + ## We're good, then. + accept + SECTION(global, acl)m4_dnl acl_smtp_connect = connect SECTION(acl, connect)m4_dnl @@ -214,16 +241,35 @@ rcpt: ## Reject if the client isn't allowed to relay and the recipient ## isn't in one of our known domains. - deny message = Relaying not permitted - !hosts = CONF_relay_clients - !authenticated = * - !domains = +known + require message = Relaying not permitted + acl = check_relay ## Ensure that the recipient is routable. require message = Invalid recipient \ ($recipient_verify_failure; $acl_verify_message) verify = recipient +SECTION(acl, misc)m4_dnl +check_relay: + ## Accept either if the client is allowed to relay through us, or if + ## we're the correct place to send this mail. + + ## Known clients and authenticated users are OK. + accept hosts = CONF_relay_clients + accept authenticated = * + + ## Known domains are OK. + accept domains = +public + + ## Finally, domains in our table are OK, unless they say they aren't. + accept domains = \ + ${if exists{CONF_sysconf_dir/domains.conf} \ + {partial0-lsearch; CONF_sysconf_dir/domains.conf}} + condition = DOMKV(service, {$value}{true}) + + ## Nope, that's not allowed. + deny + SECTION(acl, rcpt-tail)m4_dnl ## Everything checks out OK: let this one go through. accept @@ -239,7 +285,7 @@ SECTION(acl, data-tail)m4_dnl SECTION(global, acl)m4_dnl acl_smtp_expn = expn_vrfy acl_smtp_vrfy = expn_vrfy -SECTION(acl)m4_dnl +SECTION(acl, misc)m4_dnl expn_vrfy: accept hosts = +trusted deny message = Suck it and see @@ -260,31 +306,16 @@ mail_check_auth: warn set acl_c_user = $authenticated_id hosts = +thishost !authenticated = * + condition = ${if def:sender_ident} set acl_c_user = $sender_ident - ## User must be authenticated. + ## User must be authenticated by now. deny message = Sender not authenticated - !hosts = +thishost - !authenticated = * + condition = ${if !def:acl_c_user} - ## Make sure that the local part is one that the authenticated sender - ## is allowed to claim. - deny message = Sender address forbidden to calling user - !condition = ${LOOKUP_DOMAIN($sender_address_domain, - {${if and {{match_local_part \ - {$acl_c_user} \ - {+dom_users}} \ - {match_local_part \ - {$sender_address_local_part} \ - {+dom_locals}}}}}, - {${if and {{match_local_part \ - {$sender_address_local_part} \ - {+user_extaddr}} \ - {or {{eq {$sender_address_domain} \ - {}} \ - {match_domain \ - {$sender_address_domain} \ - {+public}}}}}}})} + ## Set the per-message authentication flag, since we now know that + ## there's a sensible value. + warn set acl_m_user = $acl_c_user ## All done. accept @@ -337,6 +368,22 @@ $1: DIVERT(null) ###-------------------------------------------------------------------------- +### Common routers. + +SECTION(routers, alias)m4_dnl +## Look up the local part in the address map. +alias: + driver = redirect + allow_fail = true + allow_defer = true + user = CONF_filter_user + FILTER_TRANSPORTS + local_parts = nwildlsearch; CONF_alias_file + data = ${expand:$local_part_data} +SECTION(routers, alias-opts)m4_dnl + +DIVERT(null) +###-------------------------------------------------------------------------- ### Some standard transports. m4_define(<:USER_DELIVERY:>, @@ -344,22 +391,62 @@ m4_define(<:USER_DELIVERY:>, envelope_to_add = true return_path_add = true:>) +m4_define(<:APPLY_HEADER_CHANGES:>, + <:headers_add = m4_ifelse(<:$1:>, <::>, + <:$acl_m_hdradd:>, + <:${if def:acl_m_hdradd{$acl_m_hdradd\n}}\ + $1:>) + headers_remove = m4_ifelse(<:$2:>, <::>, + <:$acl_m_hdrrm:>, + <:${if def:acl_m_hdrrm{$acl_m_hdrrm:}}\ + $2:>):>) + SECTION(transports)m4_dnl -## A standard transport for remote delivery. Try to do TLS, and don't worry -## too much if it's not very secure: the alternative is sending in plaintext -## anyway. +## A standard transport for remote delivery. By default, try to do TLS, and +## don't worry too much if it's not very secure: the alternative is sending +## in plaintext anyway. But all of this can be overridden from the +## `domains.conf' file. Annoyingly, the `tls_dh_min_bits' setting isn't +## expanded before use, so we can't set it the obvious way. Instead, encode +## it into the transport name. This is very unpleasant, of course. smtp: driver = smtp + APPLY_HEADER_CHANGES tls_require_ciphers = CONF_acceptable_ciphers tls_dh_min_bits = 1020 tls_tempfail_tryclear = true +m4_define(<:SMTP_TRANS_DHBITS:>, + <:driver = smtp + APPLY_HEADER_CHANGES + hosts_try_auth = * + hosts_require_tls = DOMKV(tls-peer-ca, {*}{}) + hosts_require_auth = \ + ${if bool {DOMKV(require-auth, {$value}{false})} {*}{}} + tls_certificate = DOMKV(tls-certificate, {${expand:$value}}fail) + tls_privatekey = DOMKV(tls-private-key, {${expand:$value}}fail) + tls_verify_certificates = DOMKV(tls-peer-ca, {${expand:$value}}fail) + tls_require_ciphers = \ + DOMKV(tls-ciphers, + {${extract {${expand:$value}} \ + { good = CONF_good_ciphers \ + any = CONF_acceptable_ciphers } \ + {$value} \ + {${expand:$value}}}} \ + {CONF_acceptable_ciphers}) + tls_dh_min_bits = $1 + tls_tempfail_tryclear = true:>)m4_dnl +smtp_dhbits_1024: + SMTP_TRANS_DHBITS(1020) +smtp_dhbits_2048: + SMTP_TRANS_DHBITS(2046) + ## Transport to a local SMTP server; use TLS and perform client ## authentication. smtp_local: driver = smtp + APPLY_HEADER_CHANGES hosts_require_tls = * - tls_certificate = CONF_sysconf_dir/client.cert + tls_certificate = CONF_sysconf_dir/client.certlist tls_privatekey = CONF_sysconf_dir/client.key tls_verify_certificates = CONF_ca_dir/ca.cert tls_require_ciphers = CONF_good_ciphers @@ -372,6 +459,7 @@ smtp_local: ## A standard transport for local delivery. deliver: driver = appendfile + APPLY_HEADER_CHANGES file = /var/mail/$local_part group = mail mode = 0600 @@ -381,17 +469,20 @@ deliver: ## Transports for user filters. mailbox: driver = appendfile + APPLY_HEADER_CHANGES initgroups = true USER_DELIVERY maildir: driver = appendfile + APPLY_HEADER_CHANGES maildir_format = true initgroups = true USER_DELIVERY pipe: driver = pipe + APPLY_HEADER_CHANGES path = ${if and {{def:home} {exists{$home/bin}}} {$home/bin:} {}}\ /usr/local/bin:/usr/local/sbin:\ /usr/bin:/usr/sbin:/bin:/sbin