1 /* $NetBSD: smtpd.h,v 1.1.1.4 2013/01/02 18:59:09 tron Exp $ */ 2 3 /*++ 4 /* NAME 5 /* smtpd 3h 6 /* SUMMARY 7 /* smtp server 8 /* SYNOPSIS 9 /* include "smtpd.h" 10 /* DESCRIPTION 11 /* .nf 12 13 /* 14 * System library. 15 */ 16 #include <sys/time.h> 17 #include <unistd.h> 18 19 /* 20 * Utility library. 21 */ 22 #include <vstream.h> 23 #include <vstring.h> 24 #include <argv.h> 25 #include <myaddrinfo.h> 26 27 /* 28 * Global library. 29 */ 30 #include <mail_stream.h> 31 32 /* 33 * Postfix TLS library. 34 */ 35 #include <tls.h> 36 37 /* 38 * Milter library. 39 */ 40 #include <milter.h> 41 42 /* 43 * Variables that keep track of conversation state. There is only one SMTP 44 * conversation at a time, so the state variables can be made global. And 45 * some of this has to be global anyway, so that the run-time error handler 46 * can clean up in case of a fatal error deep down in some library routine. 47 */ 48 typedef struct SMTPD_DEFER { 49 int active; /* is this active */ 50 VSTRING *reason; /* reason for deferral */ 51 VSTRING *dsn; /* DSN detail */ 52 int code; /* SMTP reply code */ 53 int class; /* error notification class */ 54 } SMTPD_DEFER; 55 56 typedef struct { 57 int flags; /* XFORWARD server state */ 58 char *name; /* name for access control */ 59 char *addr; /* address for access control */ 60 char *port; /* port for logging */ 61 char *namaddr; /* name[address]:port */ 62 char *rfc_addr; /* address for RFC 2821 */ 63 char *protocol; /* email protocol */ 64 char *helo_name; /* helo/ehlo parameter */ 65 char *ident; /* local message identifier */ 66 char *domain; /* rewrite context */ 67 } SMTPD_XFORWARD_ATTR; 68 69 typedef struct { 70 int flags; /* see below */ 71 int err; /* cleanup server/queue file errors */ 72 VSTREAM *client; /* SMTP client handle */ 73 VSTRING *buffer; /* SMTP client buffer */ 74 VSTRING *addr_buf; /* internalized address buffer */ 75 char *service; /* for event rate control */ 76 struct timeval arrival_time; /* start of MAIL FROM transaction */ 77 char *name; /* verified client hostname */ 78 char *reverse_name; /* unverified client hostname */ 79 char *addr; /* client host address string */ 80 char *port; /* port for logging */ 81 char *namaddr; /* name[address]:port */ 82 char *rfc_addr; /* address for RFC 2821 */ 83 int addr_family; /* address family */ 84 struct sockaddr_storage sockaddr; /* binary client endpoint */ 85 int name_status; /* 2=ok 4=soft 5=hard 6=forged */ 86 int reverse_name_status; /* 2=ok 4=soft 5=hard */ 87 int conn_count; /* connections from this client */ 88 int conn_rate; /* connection rate for this client */ 89 int error_count; /* reset after DOT */ 90 int error_mask; /* client errors */ 91 int notify_mask; /* what to report to postmaster */ 92 char *helo_name; /* client HELO/EHLO argument */ 93 char *queue_id; /* from cleanup server/queue file */ 94 VSTREAM *cleanup; /* cleanup server/queue file handle */ 95 MAIL_STREAM *dest; /* another server/file handle */ 96 int rcpt_count; /* number of accepted recipients */ 97 char *access_denied; /* fixme */ 98 ARGV *history; /* protocol transcript */ 99 char *reason; /* cause of connection loss */ 100 char *sender; /* sender address */ 101 char *encoding; /* owned by mail_cmd() */ 102 char *verp_delims; /* owned by mail_cmd() */ 103 char *recipient; /* recipient address */ 104 char *etrn_name; /* client ETRN argument */ 105 char *protocol; /* SMTP or ESMTP */ 106 char *where; /* protocol stage */ 107 int recursion; /* Kellerspeicherpegelanzeiger */ 108 off_t msg_size; /* MAIL FROM message size */ 109 off_t act_size; /* END-OF-DATA message size */ 110 int junk_cmds; /* counter */ 111 int rcpt_overshoot; /* counter */ 112 char *rewrite_context; /* address rewriting context */ 113 114 /* 115 * SASL specific. 116 */ 117 #ifdef USE_SASL_AUTH 118 struct XSASL_SERVER *sasl_server; 119 VSTRING *sasl_reply; 120 char *sasl_mechanism_list; 121 char *sasl_method; 122 char *sasl_username; 123 char *sasl_sender; 124 #endif 125 126 /* 127 * Specific to smtpd access checks. 128 */ 129 int sender_rcptmap_checked; /* sender validated against maps */ 130 int recipient_rcptmap_checked; /* recipient validated against maps */ 131 int warn_if_reject; /* force reject into warning */ 132 SMTPD_DEFER defer_if_reject; /* force reject into deferral */ 133 SMTPD_DEFER defer_if_permit; /* force permit into deferral */ 134 int defer_if_permit_client; /* force permit into warning */ 135 int defer_if_permit_helo; /* force permit into warning */ 136 int defer_if_permit_sender; /* force permit into warning */ 137 int discard; /* discard message */ 138 char *saved_filter; /* postponed filter action */ 139 char *saved_redirect; /* postponed redirect action */ 140 char *saved_bcc; /* postponed bcc action */ 141 int saved_flags; /* postponed hold/discard */ 142 #ifdef DELAY_ACTION 143 int saved_delay; /* postponed deferred delay */ 144 #endif 145 VSTRING *expand_buf; /* scratch space for $name expansion */ 146 ARGV *prepend; /* prepended headers */ 147 VSTRING *instance; /* policy query correlation */ 148 int seqno; /* policy query correlation */ 149 int ehlo_discard_mask; /* suppressed EHLO features */ 150 char *dsn_envid; /* temporary MAIL FROM state */ 151 int dsn_ret; /* temporary MAIL FROM state */ 152 VSTRING *dsn_buf; /* scratch space for xtext expansion */ 153 VSTRING *dsn_orcpt_buf; /* scratch space for ORCPT parsing */ 154 155 /* 156 * Pass-through proxy client. 157 */ 158 struct SMTPD_PROXY *proxy; 159 char *proxy_mail; /* owned by mail_cmd() */ 160 161 /* 162 * XFORWARD server state. 163 */ 164 SMTPD_XFORWARD_ATTR xforward; /* up-stream logging info */ 165 166 /* 167 * TLS related state. 168 */ 169 #ifdef USE_TLS 170 #ifdef USE_TLSPROXY 171 VSTREAM *tlsproxy; /* tlsproxy(8) temp. handle */ 172 #endif 173 TLS_SESS_STATE *tls_context; /* TLS session state */ 174 #endif 175 176 /* 177 * Milter support. 178 */ 179 const char **milter_argv; /* SMTP command vector */ 180 ssize_t milter_argc; /* SMTP command vector */ 181 const char *milter_reject_text; /* input to call-back from Milter */ 182 183 /* 184 * EHLO temporary space. 185 */ 186 VSTRING *ehlo_buf; 187 ARGV *ehlo_argv; 188 } SMTPD_STATE; 189 190 #define SMTPD_FLAG_HANGUP (1<<0) /* 421/521 disconnect */ 191 #define SMTPD_FLAG_ILL_PIPELINING (1<<1) /* inappropriate pipelining */ 192 #define SMTPD_FLAG_AUTH_USED (1<<2) /* don't reuse SASL state */ 193 194 /* Security: don't reset SMTPD_FLAG_AUTH_USED. */ 195 #define SMTPD_MASK_MAIL_KEEP ~0 /* keep all after MAIL reset */ 196 197 #define SMTPD_STATE_XFORWARD_INIT (1<<0) /* xforward preset done */ 198 #define SMTPD_STATE_XFORWARD_NAME (1<<1) /* client name received */ 199 #define SMTPD_STATE_XFORWARD_ADDR (1<<2) /* client address received */ 200 #define SMTPD_STATE_XFORWARD_PROTO (1<<3) /* protocol received */ 201 #define SMTPD_STATE_XFORWARD_HELO (1<<4) /* client helo received */ 202 #define SMTPD_STATE_XFORWARD_IDENT (1<<5) /* message identifier */ 203 #define SMTPD_STATE_XFORWARD_DOMAIN (1<<6) /* address context */ 204 #define SMTPD_STATE_XFORWARD_PORT (1<<7) /* client port received */ 205 206 #define SMTPD_STATE_XFORWARD_CLIENT_MASK \ 207 (SMTPD_STATE_XFORWARD_NAME | SMTPD_STATE_XFORWARD_ADDR \ 208 | SMTPD_STATE_XFORWARD_PROTO | SMTPD_STATE_XFORWARD_HELO \ 209 | SMTPD_STATE_XFORWARD_PORT) 210 211 extern void smtpd_state_init(SMTPD_STATE *, VSTREAM *, const char *); 212 extern void smtpd_state_reset(SMTPD_STATE *); 213 214 /* 215 * Conversation stages. This is used for "lost connection after XXX" 216 * diagnostics. 217 */ 218 #define SMTPD_AFTER_CONNECT "CONNECT" 219 #define SMTPD_AFTER_DATA "DATA content" 220 #define SMTPD_AFTER_DOT "END-OF-MESSAGE" 221 222 /* 223 * Other stages. These are sometimes used to change the way information is 224 * logged or what information will be available for access control. 225 */ 226 #define SMTPD_CMD_HELO "HELO" 227 #define SMTPD_CMD_EHLO "EHLO" 228 #define SMTPD_CMD_STARTTLS "STARTTLS" 229 #define SMTPD_CMD_AUTH "AUTH" 230 #define SMTPD_CMD_MAIL "MAIL" 231 #define SMTPD_CMD_RCPT "RCPT" 232 #define SMTPD_CMD_DATA "DATA" 233 #define SMTPD_CMD_EOD SMTPD_AFTER_DOT /* XXX Was: END-OF-DATA */ 234 #define SMTPD_CMD_RSET "RSET" 235 #define SMTPD_CMD_NOOP "NOOP" 236 #define SMTPD_CMD_VRFY "VRFY" 237 #define SMTPD_CMD_ETRN "ETRN" 238 #define SMTPD_CMD_QUIT "QUIT" 239 #define SMTPD_CMD_XCLIENT "XCLIENT" 240 #define SMTPD_CMD_XFORWARD "XFORWARD" 241 #define SMTPD_CMD_UNKNOWN "UNKNOWN" 242 243 /* 244 * Representation of unknown and non-existent client information. Throughout 245 * Postfix, we use the "unknown" string value for unknown client information 246 * (e.g., unknown remote client hostname), and we use the empty string, null 247 * pointer or "no queue file record" for non-existent client information 248 * (e.g., no HELO command, or local submission). 249 * 250 * Inside the SMTP server, unknown real client attributes are represented by 251 * the string "unknown", and non-existent HELO is represented as a null 252 * pointer. The SMTP server uses this same representation internally for 253 * forwarded client attributes; the XFORWARD syntax makes no distinction 254 * between unknown (remote submission) and non-existent (local submission). 255 * 256 * The SMTP client sends forwarded client attributes only when upstream client 257 * attributes exist (i.e. remote submission). Thus, local submissions will 258 * appear to come from an SMTP-based content filter, which is acceptable. 259 * 260 * Known/unknown client attribute values use the SMTP server's internal 261 * representation in queue files, in queue manager delivery requests, and in 262 * delivery agent $name expansions. 263 * 264 * Non-existent attribute values are never present in queue files. Non-existent 265 * information is represented as empty strings in queue manager delivery 266 * requests and in delivery agent $name expansions. 267 */ 268 #define CLIENT_ATTR_UNKNOWN "unknown" 269 270 #define CLIENT_NAME_UNKNOWN CLIENT_ATTR_UNKNOWN 271 #define CLIENT_ADDR_UNKNOWN CLIENT_ATTR_UNKNOWN 272 #define CLIENT_PORT_UNKNOWN CLIENT_ATTR_UNKNOWN 273 #define CLIENT_NAMADDR_UNKNOWN CLIENT_ATTR_UNKNOWN 274 #define CLIENT_HELO_UNKNOWN 0 275 #define CLIENT_PROTO_UNKNOWN CLIENT_ATTR_UNKNOWN 276 #define CLIENT_IDENT_UNKNOWN 0 277 #define CLIENT_DOMAIN_UNKNOWN 0 278 #define CLIENT_LOGIN_UNKNOWN 0 279 280 #define IS_AVAIL_CLIENT_ATTR(v) ((v) && strcmp((v), CLIENT_ATTR_UNKNOWN)) 281 282 #define IS_AVAIL_CLIENT_NAME(v) IS_AVAIL_CLIENT_ATTR(v) 283 #define IS_AVAIL_CLIENT_ADDR(v) IS_AVAIL_CLIENT_ATTR(v) 284 #define IS_AVAIL_CLIENT_PORT(v) IS_AVAIL_CLIENT_ATTR(v) 285 #define IS_AVAIL_CLIENT_NAMADDR(v) IS_AVAIL_CLIENT_ATTR(v) 286 #define IS_AVAIL_CLIENT_HELO(v) ((v) != 0) 287 #define IS_AVAIL_CLIENT_PROTO(v) IS_AVAIL_CLIENT_ATTR(v) 288 #define IS_AVAIL_CLIENT_IDENT(v) ((v) != 0) 289 #define IS_AVAIL_CLIENT_DOMAIN(v) ((v) != 0) 290 291 /* 292 * If running in stand-alone mode, do not try to talk to Postfix daemons but 293 * write to queue file instead. 294 */ 295 #define SMTPD_STAND_ALONE_STREAM(stream) \ 296 (stream == VSTREAM_IN && getuid() != var_owner_uid) 297 298 #define SMTPD_STAND_ALONE(state) \ 299 (state->client == VSTREAM_IN && getuid() != var_owner_uid) 300 301 /* 302 * If running as proxy front-end, disable actions that require communication 303 * with the cleanup server. 304 */ 305 #define USE_SMTPD_PROXY(state) \ 306 (SMTPD_STAND_ALONE(state) == 0 && *var_smtpd_proxy_filt) 307 308 /* 309 * SMTPD peer information lookup. 310 */ 311 extern void smtpd_peer_init(SMTPD_STATE *state); 312 extern void smtpd_peer_reset(SMTPD_STATE *state); 313 314 #define SMTPD_PEER_CODE_OK 2 315 #define SMTPD_PEER_CODE_TEMP 4 316 #define SMTPD_PEER_CODE_PERM 5 317 #define SMTPD_PEER_CODE_FORGED 6 318 319 /* 320 * Construct name[addr] or name[addr]:port as appropriate 321 */ 322 #define SMTPD_BUILD_NAMADDRPORT(name, addr, port) \ 323 concatenate((name), "[", (addr), "]", \ 324 var_smtpd_client_port_log ? ":" : (char *) 0, \ 325 (port), (char *) 0) 326 327 /* 328 * Don't mix information from the current SMTP session with forwarded 329 * information from an up-stream session. 330 */ 331 #define HAVE_FORWARDED_CLIENT_ATTR(s) \ 332 ((s)->xforward.flags & SMTPD_STATE_XFORWARD_CLIENT_MASK) 333 334 #define FORWARD_CLIENT_ATTR(s, a) \ 335 (HAVE_FORWARDED_CLIENT_ATTR(s) ? \ 336 (s)->xforward.a : (s)->a) 337 338 #define FORWARD_ADDR(s) FORWARD_CLIENT_ATTR((s), rfc_addr) 339 #define FORWARD_NAME(s) FORWARD_CLIENT_ATTR((s), name) 340 #define FORWARD_NAMADDR(s) FORWARD_CLIENT_ATTR((s), namaddr) 341 #define FORWARD_PROTO(s) FORWARD_CLIENT_ATTR((s), protocol) 342 #define FORWARD_HELO(s) FORWARD_CLIENT_ATTR((s), helo_name) 343 #define FORWARD_PORT(s) FORWARD_CLIENT_ATTR((s), port) 344 345 /* 346 * Mixing is not a problem with forwarded local message identifiers. 347 */ 348 #define HAVE_FORWARDED_IDENT(s) \ 349 ((s)->xforward.ident != 0) 350 351 #define FORWARD_IDENT(s) \ 352 (HAVE_FORWARDED_IDENT(s) ? \ 353 (s)->xforward.ident : (s)->queue_id) 354 355 /* 356 * Mixing is not a problem with forwarded address rewriting contexts. 357 */ 358 #define FORWARD_DOMAIN(s) \ 359 (((s)->xforward.flags & SMTPD_STATE_XFORWARD_DOMAIN) ? \ 360 (s)->xforward.domain : (s)->rewrite_context) 361 362 extern void smtpd_xforward_init(SMTPD_STATE *); 363 extern void smtpd_xforward_preset(SMTPD_STATE *); 364 extern void smtpd_xforward_reset(SMTPD_STATE *); 365 366 /* 367 * Transparency: before mail is queued, do we check for unknown recipients, 368 * do we allow address mapping, automatic bcc, header/body checks? 369 */ 370 extern int smtpd_input_transp_mask; 371 372 /* 373 * More Milter support. 374 */ 375 extern MILTERS *smtpd_milters; 376 377 /* 378 * Message size multiplication factor for free space check. 379 */ 380 extern double smtpd_space_multf; 381 382 /* LICENSE 383 /* .ad 384 /* .fi 385 /* The Secure Mailer license must be distributed with this software. 386 /* AUTHOR(S) 387 /* Wietse Venema 388 /* IBM T.J. Watson Research 389 /* P.O. Box 704 390 /* Yorktown Heights, NY 10598, USA 391 /* 392 /* TLS support originally by: 393 /* Lutz Jaenicke 394 /* BTU Cottbus 395 /* Allgemeine Elektrotechnik 396 /* Universitaetsplatz 3-4 397 /* D-03044 Cottbus, Germany 398 /*--*/ 399