/* $NetBSD: smtpd.h,v 1.2 2017/02/14 01:16:48 christos Exp $ */
/*++
/* NAME
/* smtpd 3h
/* SUMMARY
/* smtp server
/* SYNOPSIS
/* include "smtpd.h"
/* DESCRIPTION
/* .nf
/*
* System library.
*/
#include <sys/time.h>
#include <unistd.h>
/*
* Utility library.
*/
#include <vstream.h>
#include <vstring.h>
#include <argv.h>
#include <myaddrinfo.h>
/*
* Global library.
*/
#include <mail_stream.h>
/*
* Postfix TLS library.
*/
#include <tls.h>
/*
* Milter library.
*/
#include <milter.h>
/*
* Variables that keep track of conversation state. There is only one SMTP
* conversation at a time, so the state variables can be made global. And
* some of this has to be global anyway, so that the run-time error handler
* can clean up in case of a fatal error deep down in some library routine.
*/
typedef struct SMTPD_DEFER {
int active; /* is this active */
VSTRING *reason; /* reason for deferral */
VSTRING *dsn; /* DSN detail */
int code; /* SMTP reply code */
int class; /* error notification class */
} SMTPD_DEFER;
typedef struct {
int flags; /* XFORWARD server state */
char *name; /* name for access control */
char *addr; /* address for access control */
char *port; /* port for logging */
char *namaddr; /* name[address]:port */
char *rfc_addr; /* address for RFC 2821 */
char *protocol; /* email protocol */
char *helo_name; /* helo/ehlo parameter */
char *ident; /* local message identifier */
char *domain; /* rewrite context */
} SMTPD_XFORWARD_ATTR;
typedef struct {
int flags; /* see below */
int err; /* cleanup server/queue file errors */
VSTREAM *client; /* SMTP client handle */
VSTRING *buffer; /* SMTP client buffer */
VSTRING *addr_buf; /* internalized address buffer */
char *service; /* for event rate control */
struct timeval arrival_time; /* start of MAIL FROM transaction */
char *name; /* verified client hostname */
char *reverse_name; /* unverified client hostname */
char *addr; /* client host address string */
char *port; /* port for logging */
char *namaddr; /* name[address]:port */
char *rfc_addr; /* address for RFC 2821 */
int addr_family; /* address family */
char *dest_addr; /* for Dovecot AUTH */
struct sockaddr_storage sockaddr; /* binary client endpoint */
SOCKADDR_SIZE sockaddr_len; /* binary client endpoint */
int name_status; /* 2=ok 4=soft 5=hard 6=forged */
int reverse_name_status; /* 2=ok 4=soft 5=hard */
int conn_count; /* connections from this client */
int conn_rate; /* connection rate for this client */
int error_count; /* reset after DOT */
int error_mask; /* client errors */
int notify_mask; /* what to report to postmaster */
char *helo_name; /* client HELO/EHLO argument */
char *queue_id; /* from cleanup server/queue file */
VSTREAM *cleanup; /* cleanup server/queue file handle */
MAIL_STREAM *dest; /* another server/file handle */
int rcpt_count; /* number of accepted recipients */
char *access_denied; /* fixme */
ARGV *history; /* protocol transcript */
char *reason; /* cause of connection loss */
char *sender; /* sender address */
char *encoding; /* owned by mail_cmd() */
char *verp_delims; /* owned by mail_cmd() */
char *recipient; /* recipient address */
char *etrn_name; /* client ETRN argument */
char *protocol; /* SMTP or ESMTP */
char *where; /* protocol stage */
int recursion; /* Kellerspeicherpegelanzeiger */
off_t msg_size; /* MAIL FROM message size */
off_t act_size; /* END-OF-DATA message size */
int junk_cmds; /* counter */
int rcpt_overshoot; /* counter */
char *rewrite_context; /* address rewriting context */
/*
* SASL specific.
*/
#ifdef USE_SASL_AUTH
struct XSASL_SERVER *sasl_server;
VSTRING *sasl_reply;
char *sasl_mechanism_list;
char *sasl_method;
char *sasl_username;
char *sasl_sender;
#endif
/*
* Specific to smtpd access checks.
*/
int sender_rcptmap_checked; /* sender validated against maps */
int recipient_rcptmap_checked; /* recipient validated against maps */
int warn_if_reject; /* force reject into warning */
SMTPD_DEFER defer_if_reject; /* force reject into deferral */
SMTPD_DEFER defer_if_permit; /* force permit into deferral */
int defer_if_permit_client; /* force permit into warning */
int defer_if_permit_helo; /* force permit into warning */
int defer_if_permit_sender; /* force permit into warning */
int discard; /* discard message */
char *saved_filter; /* postponed filter action */
char *saved_redirect; /* postponed redirect action */
char *saved_bcc; /* postponed bcc action */
int saved_flags; /* postponed hold/discard */
#ifdef DELAY_ACTION
int saved_delay; /* postponed deferred delay */
#endif
VSTRING *expand_buf; /* scratch space for $name expansion */
ARGV *prepend; /* prepended headers */
VSTRING *instance; /* policy query correlation */
int seqno; /* policy query correlation */
int ehlo_discard_mask; /* suppressed EHLO features */
char *dsn_envid; /* temporary MAIL FROM state */
int dsn_ret; /* temporary MAIL FROM state */
VSTRING *dsn_buf; /* scratch space for xtext expansion */
VSTRING *dsn_orcpt_buf; /* scratch space for ORCPT parsing */
/*
* Pass-through proxy client.
*/
struct SMTPD_PROXY *proxy;
char *proxy_mail; /* owned by mail_cmd() */
/*
* XFORWARD server state.
*/
SMTPD_XFORWARD_ATTR xforward; /* up-stream logging info */
/*
* TLS related state.
*/
#ifdef USE_TLS
#ifdef USE_TLSPROXY
VSTREAM *tlsproxy; /* tlsproxy(8) temp. handle */
#endif
TLS_SESS_STATE *tls_context; /* TLS session state */
#endif
/*
* Milter support.
*/
const char **milter_argv; /* SMTP command vector */
ssize_t milter_argc; /* SMTP command vector */
const char *milter_reject_text; /* input to call-back from Milter */
/*
* EHLO temporary space.
*/
VSTRING *ehlo_buf;
ARGV *ehlo_argv;
} SMTPD_STATE;
#define SMTPD_FLAG_HANGUP (1<<0) /* 421/521 disconnect */
#define SMTPD_FLAG_ILL_PIPELINING (1<<1) /* inappropriate pipelining */
#define SMTPD_FLAG_AUTH_USED (1<<2) /* don't reuse SASL state */
#define SMTPD_FLAG_SMTPUTF8 (1<<3) /* RFC 6531/2 transaction */
/* Security: don't reset SMTPD_FLAG_AUTH_USED. */
#define SMTPD_MASK_MAIL_KEEP \
~(SMTPD_FLAG_SMTPUTF8) /* Fix 20140706 */
#define SMTPD_STATE_XFORWARD_INIT (1<<0) /* xforward preset done */
#define SMTPD_STATE_XFORWARD_NAME (1<<1) /* client name received */
#define SMTPD_STATE_XFORWARD_ADDR (1<<2) /* client address received */
#define SMTPD_STATE_XFORWARD_PROTO (1<<3) /* protocol received */
#define SMTPD_STATE_XFORWARD_HELO (1<<4) /* client helo received */
#define SMTPD_STATE_XFORWARD_IDENT (1<<5) /* message identifier */
#define SMTPD_STATE_XFORWARD_DOMAIN (1<<6) /* address context */
#define SMTPD_STATE_XFORWARD_PORT (1<<7) /* client port received */
#define SMTPD_STATE_XFORWARD_CLIENT_MASK \
(SMTPD_STATE_XFORWARD_NAME | SMTPD_STATE_XFORWARD_ADDR \
| SMTPD_STATE_XFORWARD_PROTO | SMTPD_STATE_XFORWARD_HELO \
| SMTPD_STATE_XFORWARD_PORT)
extern void smtpd_state_init(SMTPD_STATE *, VSTREAM *, const char *);
extern void smtpd_state_reset(SMTPD_STATE *);
/*
* Conversation stages. This is used for "lost connection after XXX"
* diagnostics.
*/
#define SMTPD_AFTER_CONNECT "CONNECT"
#define SMTPD_AFTER_DATA "DATA content"
#define SMTPD_AFTER_DOT "END-OF-MESSAGE"
/*
* Other stages. These are sometimes used to change the way information is
* logged or what information will be available for access control.
*/
#define SMTPD_CMD_HELO "HELO"
#define SMTPD_CMD_EHLO "EHLO"
#define SMTPD_CMD_STARTTLS "STARTTLS"
#define SMTPD_CMD_AUTH "AUTH"
#define SMTPD_CMD_MAIL "MAIL"
#define SMTPD_CMD_RCPT "RCPT"
#define SMTPD_CMD_DATA "DATA"
#define SMTPD_CMD_EOD SMTPD_AFTER_DOT /* XXX Was: END-OF-DATA */
#define SMTPD_CMD_RSET "RSET"
#define SMTPD_CMD_NOOP "NOOP"
#define SMTPD_CMD_VRFY "VRFY"
#define SMTPD_CMD_ETRN "ETRN"
#define SMTPD_CMD_QUIT "QUIT"
#define SMTPD_CMD_XCLIENT "XCLIENT"
#define SMTPD_CMD_XFORWARD "XFORWARD"
#define SMTPD_CMD_UNKNOWN "UNKNOWN"
/*
* Representation of unknown and non-existent client information. Throughout
* Postfix, we use the "unknown" string value for unknown client information
* (e.g., unknown remote client hostname), and we use the empty string, null
* pointer or "no queue file record" for non-existent client information
* (e.g., no HELO command, or local submission).
*
* Inside the SMTP server, unknown real client attributes are represented by
* the string "unknown", and non-existent HELO is represented as a null
* pointer. The SMTP server uses this same representation internally for
* forwarded client attributes; the XFORWARD syntax makes no distinction
* between unknown (remote submission) and non-existent (local submission).
*
* The SMTP client sends forwarded client attributes only when upstream client
* attributes exist (i.e. remote submission). Thus, local submissions will
* appear to come from an SMTP-based content filter, which is acceptable.
*
* Known/unknown client attribute values use the SMTP server's internal
* representation in queue files, in queue manager delivery requests, and in
* delivery agent $name expansions.
*
* Non-existent attribute values are never present in queue files. Non-existent
* information is represented as empty strings in queue manager delivery
* requests and in delivery agent $name expansions.
*/
#define CLIENT_ATTR_UNKNOWN "unknown"
#define CLIENT_NAME_UNKNOWN CLIENT_ATTR_UNKNOWN
#define CLIENT_ADDR_UNKNOWN CLIENT_ATTR_UNKNOWN
#define CLIENT_PORT_UNKNOWN CLIENT_ATTR_UNKNOWN
#define CLIENT_NAMADDR_UNKNOWN CLIENT_ATTR_UNKNOWN
#define CLIENT_HELO_UNKNOWN 0
#define CLIENT_PROTO_UNKNOWN CLIENT_ATTR_UNKNOWN
#define CLIENT_IDENT_UNKNOWN 0
#define CLIENT_DOMAIN_UNKNOWN 0
#define CLIENT_LOGIN_UNKNOWN 0
#define IS_AVAIL_CLIENT_ATTR(v) ((v) && strcmp((v), CLIENT_ATTR_UNKNOWN))
#define IS_AVAIL_CLIENT_NAME(v) IS_AVAIL_CLIENT_ATTR(v)
#define IS_AVAIL_CLIENT_ADDR(v) IS_AVAIL_CLIENT_ATTR(v)
#define IS_AVAIL_CLIENT_PORT(v) IS_AVAIL_CLIENT_ATTR(v)
#define IS_AVAIL_CLIENT_NAMADDR(v) IS_AVAIL_CLIENT_ATTR(v)
#define IS_AVAIL_CLIENT_HELO(v) ((v) != 0)
#define IS_AVAIL_CLIENT_PROTO(v) IS_AVAIL_CLIENT_ATTR(v)
#define IS_AVAIL_CLIENT_IDENT(v) ((v) != 0)
#define IS_AVAIL_CLIENT_DOMAIN(v) ((v) != 0)
/*
* If running in stand-alone mode, do not try to talk to Postfix daemons but
* write to queue file instead.
*/
#define SMTPD_STAND_ALONE_STREAM(stream) \
(stream == VSTREAM_IN && getuid() != var_owner_uid)
#define SMTPD_STAND_ALONE(state) \
(state->client == VSTREAM_IN && getuid() != var_owner_uid)
/*
* If running as proxy front-end, disable actions that require communication
* with the cleanup server.
*/
#define USE_SMTPD_PROXY(state) \
(SMTPD_STAND_ALONE(state) == 0 && *var_smtpd_proxy_filt)
/*
* Are we in a MAIL transaction?
*/
#define SMTPD_IN_MAIL_TRANSACTION(state) ((state)->sender != 0)
/*
* SMTPD peer information lookup.
*/
extern void smtpd_peer_init(SMTPD_STATE *state);
extern void smtpd_peer_reset(SMTPD_STATE *state);
extern int smtpd_peer_from_haproxy(SMTPD_STATE *state);
#define SMTPD_PEER_CODE_OK 2
#define SMTPD_PEER_CODE_TEMP 4
#define SMTPD_PEER_CODE_PERM 5
#define SMTPD_PEER_CODE_FORGED 6
/*
* Construct name[addr] or name[addr]:port as appropriate
*/
#define SMTPD_BUILD_NAMADDRPORT(name, addr, port) \
concatenate((name), "[", (addr), "]", \
var_smtpd_client_port_log ? ":" : (char *) 0, \
(port), (char *) 0)
/*
* Don't mix information from the current SMTP session with forwarded
* information from an up-stream session.
*/
#define HAVE_FORWARDED_CLIENT_ATTR(s) \
((s)->xforward.flags & SMTPD_STATE_XFORWARD_CLIENT_MASK)
#define FORWARD_CLIENT_ATTR(s, a) \
(HAVE_FORWARDED_CLIENT_ATTR(s) ? \
(s)->xforward.a : (s)->a)
#define FORWARD_ADDR(s) FORWARD_CLIENT_ATTR((s), rfc_addr)
#define FORWARD_NAME(s) FORWARD_CLIENT_ATTR((s), name)
#define FORWARD_NAMADDR(s) FORWARD_CLIENT_ATTR((s), namaddr)
#define FORWARD_PROTO(s) FORWARD_CLIENT_ATTR((s), protocol)
#define FORWARD_HELO(s) FORWARD_CLIENT_ATTR((s), helo_name)
#define FORWARD_PORT(s) FORWARD_CLIENT_ATTR((s), port)
/*
* Mixing is not a problem with forwarded local message identifiers.
*/
#define HAVE_FORWARDED_IDENT(s) \
((s)->xforward.ident != 0)
#define FORWARD_IDENT(s) \
(HAVE_FORWARDED_IDENT(s) ? \
(s)->xforward.ident : (s)->queue_id)
/*
* Mixing is not a problem with forwarded address rewriting contexts.
*/
#define FORWARD_DOMAIN(s) \
(((s)->xforward.flags & SMTPD_STATE_XFORWARD_DOMAIN) ? \
(s)->xforward.domain : (s)->rewrite_context)
extern void smtpd_xforward_init(SMTPD_STATE *);
extern void smtpd_xforward_preset(SMTPD_STATE *);
extern void smtpd_xforward_reset(SMTPD_STATE *);
/*
* Transparency: before mail is queued, do we check for unknown recipients,
* do we allow address mapping, automatic bcc, header/body checks?
*/
extern int smtpd_input_transp_mask;
/*
* More Milter support.
*/
extern MILTERS *smtpd_milters;
/*
* Message size multiplication factor for free space check.
*/
extern double smtpd_space_multf;
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*
/* TLS support originally by:
/* Lutz Jaenicke
/* BTU Cottbus
/* Allgemeine Elektrotechnik
/* Universitaetsplatz 3-4
/* D-03044 Cottbus, Germany
/*--*/