1 /* 2 * Copyright (c) 1999-2002 Sendmail, Inc. and its suppliers. 3 * All rights reserved. 4 * 5 * By using this file, you agree to the terms and conditions set 6 * forth in the LICENSE file which can be found at the top level of 7 * the sendmail distribution. 8 * 9 * 10 * $Id: mfapi.h,v 8.41 2002/03/22 21:36:12 gshapiro Exp $ 11 */ 12 13 /* 14 ** MFAPI.H -- Global definitions for mail filter library and mail filters. 15 */ 16 17 #ifndef _LIBMILTER_MFAPI_H 18 # define _LIBMILTER_MFAPI_H 1 19 20 # include <sys/types.h> 21 # include <sys/socket.h> 22 # include "libmilter/mfdef.h" 23 24 # define LIBMILTER_API extern 25 26 27 #ifndef _SOCK_ADDR 28 # define _SOCK_ADDR struct sockaddr 29 #endif /* ! _SOCK_ADDR */ 30 31 /* 32 ** libmilter functions return one of the following to indicate 33 ** success/failure: 34 */ 35 36 #define MI_SUCCESS 0 37 #define MI_FAILURE (-1) 38 39 /* "forward" declarations */ 40 typedef struct smfi_str SMFICTX; 41 typedef struct smfi_str *SMFICTX_PTR; 42 43 typedef struct smfiDesc smfiDesc_str; 44 typedef struct smfiDesc *smfiDesc_ptr; 45 46 /* 47 ** Type which callbacks should return to indicate message status. 48 ** This may take on one of the SMFIS_* values listed below. 49 */ 50 51 typedef int sfsistat; 52 53 #if defined(__linux__) && defined(__GNUC__) && defined(__cplusplus) && __GNUC_MINOR__ >= 8 54 # define SM__P(X) __PMT(X) 55 #else /* __linux__ && __GNUC__ && __cplusplus && _GNUC_MINOR__ >= 8 */ 56 # define SM__P(X) __P(X) 57 #endif /* __linux__ && __GNUC__ && __cplusplus && _GNUC_MINOR__ >= 8 */ 58 59 /* Some platforms don't define __P -- do it for them here: */ 60 #ifndef __P 61 # ifdef __STDC__ 62 # define __P(X) X 63 # else /* __STDC__ */ 64 # define __P(X) () 65 # endif /* __STDC__ */ 66 #endif /* __P */ 67 68 /* 69 ** structure describing one milter 70 */ 71 72 struct smfiDesc 73 { 74 char *xxfi_name; /* filter name */ 75 int xxfi_version; /* version code -- do not change */ 76 unsigned long xxfi_flags; /* flags */ 77 78 /* connection info filter */ 79 sfsistat (*xxfi_connect) SM__P((SMFICTX *, char *, _SOCK_ADDR *)); 80 81 /* SMTP HELO command filter */ 82 sfsistat (*xxfi_helo) SM__P((SMFICTX *, char *)); 83 84 /* envelope sender filter */ 85 sfsistat (*xxfi_envfrom) SM__P((SMFICTX *, char **)); 86 87 /* envelope recipient filter */ 88 sfsistat (*xxfi_envrcpt) SM__P((SMFICTX *, char **)); 89 90 /* header filter */ 91 sfsistat (*xxfi_header) SM__P((SMFICTX *, char *, char *)); 92 93 /* end of header */ 94 sfsistat (*xxfi_eoh) SM__P((SMFICTX *)); 95 96 /* body block */ 97 sfsistat (*xxfi_body) SM__P((SMFICTX *, unsigned char *, size_t)); 98 99 /* end of message */ 100 sfsistat (*xxfi_eom) SM__P((SMFICTX *)); 101 102 /* message aborted */ 103 sfsistat (*xxfi_abort) SM__P((SMFICTX *)); 104 105 /* connection cleanup */ 106 sfsistat (*xxfi_close) SM__P((SMFICTX *)); 107 }; 108 109 LIBMILTER_API int smfi_register __P((struct smfiDesc)); 110 LIBMILTER_API int smfi_main __P((void)); 111 LIBMILTER_API int smfi_setbacklog __P((int)); 112 LIBMILTER_API int smfi_setdbg __P((int)); 113 LIBMILTER_API int smfi_settimeout __P((int)); 114 LIBMILTER_API int smfi_setconn __P((char *)); 115 LIBMILTER_API int smfi_stop __P((void)); 116 117 #define SMFI_VERSION 2 /* version number */ 118 119 /* 120 ** What the filter might do -- values to be ORed together for 121 ** smfiDesc.xxfi_flags. 122 */ 123 124 #define SMFIF_NONE 0x00000000L /* no flags */ 125 #define SMFIF_ADDHDRS 0x00000001L /* filter may add headers */ 126 #define SMFIF_CHGBODY 0x00000002L /* filter may replace body */ 127 #define SMFIF_MODBODY SMFIF_CHGBODY /* backwards compatible */ 128 #define SMFIF_ADDRCPT 0x00000004L /* filter may add recipients */ 129 #define SMFIF_DELRCPT 0x00000008L /* filter may delete recipients */ 130 #define SMFIF_CHGHDRS 0x00000010L /* filter may change/delete headers */ 131 #if _FFR_QUARANTINE 132 # define SMFIF_QUARANTINE 0x00000020L /* filter may quarantine envelope */ 133 #endif /* _FFR_QUARANTINE */ 134 135 /* 136 ** Continue processing message/connection. 137 */ 138 139 #define SMFIS_CONTINUE 0 140 141 /* 142 ** Reject the message/connection. 143 ** No further routines will be called for this message 144 ** (or connection, if returned from a connection-oriented routine). 145 */ 146 147 #define SMFIS_REJECT 1 148 149 /* 150 ** Accept the message, 151 ** but silently discard the message. 152 ** No further routines will be called for this message. 153 ** This is only meaningful from message-oriented routines. 154 */ 155 156 #define SMFIS_DISCARD 2 157 158 /* 159 ** Accept the message/connection. 160 ** No further routines will be called for this message 161 ** (or connection, if returned from a connection-oriented routine; 162 ** in this case, it causes all messages on this connection 163 ** to be accepted without filtering). 164 */ 165 166 #define SMFIS_ACCEPT 3 167 168 /* 169 ** Return a temporary failure, i.e., 170 ** the corresponding SMTP command will return a 4xx status code. 171 ** In some cases this may prevent further routines from 172 ** being called on this message or connection, 173 ** although in other cases (e.g., when processing an envelope 174 ** recipient) processing of the message will continue. 175 */ 176 177 #define SMFIS_TEMPFAIL 4 178 179 #if 0 180 /* 181 ** Filter Routine Details 182 */ 183 184 /* connection info filter */ 185 extern sfsistat xxfi_connect __P((SMFICTX *, char *, _SOCK_ADDR *)); 186 187 /* 188 ** xxfi_connect(ctx, hostname, hostaddr) Invoked on each connection 189 ** 190 ** char *hostname; Host domain name, as determined by a reverse lookup 191 ** on the host address. 192 ** _SOCK_ADDR *hostaddr; Host address, as determined by a getpeername 193 ** call on the SMTP socket. 194 */ 195 196 /* SMTP HELO command filter */ 197 extern sfsistat xxfi_helo __P((SMFICTX *, char *)); 198 199 /* 200 ** xxfi_helo(ctx, helohost) Invoked on SMTP HELO/EHLO command 201 ** 202 ** char *helohost; Value passed to HELO/EHLO command, which should be 203 ** the domain name of the sending host (but is, in practice, 204 ** anything the sending host wants to send). 205 */ 206 207 /* envelope sender filter */ 208 extern sfsistat xxfi_envfrom __P((SMFICTX *, char **)); 209 210 /* 211 ** xxfi_envfrom(ctx, argv) Invoked on envelope from 212 ** 213 ** char **argv; Null-terminated SMTP command arguments; 214 ** argv[0] is guaranteed to be the sender address. 215 ** Later arguments are the ESMTP arguments. 216 */ 217 218 /* envelope recipient filter */ 219 extern sfsistat xxfi_envrcpt __P((SMFICTX *, char **)); 220 221 /* 222 ** xxfi_envrcpt(ctx, argv) Invoked on each envelope recipient 223 ** 224 ** char **argv; Null-terminated SMTP command arguments; 225 ** argv[0] is guaranteed to be the recipient address. 226 ** Later arguments are the ESMTP arguments. 227 */ 228 229 /* header filter */ 230 extern sfsistat xxfi_header __P((SMFICTX *, char *, char *)); 231 232 /* 233 ** xxfi_header(ctx, headerf, headerv) Invoked on each message header. The 234 ** content of the header may have folded white space (that is, multiple 235 ** lines with following white space) included. 236 ** 237 ** char *headerf; Header field name 238 ** char *headerv; Header field value 239 */ 240 241 /* end of header */ 242 extern sfsistat xxfi_eoh __P((SMFICTX *)); 243 244 /* 245 ** xxfi_eoh(ctx) Invoked at end of header 246 */ 247 248 /* body block */ 249 extern sfsistat xxfi_body __P((SMFICTX *, unsigned char *, size_t)); 250 251 /* 252 ** xxfi_body(ctx, bodyp, bodylen) Invoked for each body chunk. There may 253 ** be multiple body chunks passed to the filter. End-of-lines are 254 ** represented as received from SMTP (normally Carriage-Return/Line-Feed). 255 ** 256 ** unsigned char *bodyp; Pointer to body data 257 ** size_t bodylen; Length of body data 258 */ 259 260 /* end of message */ 261 extern sfsistat xxfi_eom __P((SMFICTX *)); 262 263 /* 264 ** xxfi_eom(ctx) Invoked at end of message. This routine can perform 265 ** special operations such as modifying the message header, body, or 266 ** envelope. 267 */ 268 269 /* message aborted */ 270 extern sfsistat xxfi_abort __P((SMFICTX *)); 271 272 /* 273 ** xxfi_abort(ctx) Invoked if message is aborted outside of the control of 274 ** the filter, for example, if the SMTP sender issues an RSET command. If 275 ** xxfi_abort is called, xxfi_eom will not be called and vice versa. 276 */ 277 278 /* connection cleanup */ 279 extern sfsistat xxfi_close __P((SMFICTX *)); 280 281 /* 282 ** xxfi_close(ctx) Invoked at end of the connection. This is called on 283 ** close even if the previous mail transaction was aborted. 284 */ 285 #endif /* 0 */ 286 287 /* 288 ** Additional information is passed in to the vendor filter routines using 289 ** symbols. Symbols correspond closely to sendmail macros. The symbols 290 ** defined depend on the context. The value of a symbol is accessed using: 291 */ 292 293 /* Return the value of a symbol. */ 294 LIBMILTER_API char * smfi_getsymval __P((SMFICTX *, char *)); 295 296 /* 297 ** Return the value of a symbol. 298 ** 299 ** SMFICTX *ctx; Opaque context structure 300 ** char *symname; The name of the symbol to access. 301 */ 302 303 /* 304 ** Vendor filter routines that want to pass additional information back to 305 ** the MTA for use in SMTP replies may call smfi_setreply before returning. 306 */ 307 308 LIBMILTER_API int smfi_setreply __P((SMFICTX *, char *, char *, char *)); 309 310 #if _FFR_MULTILINE 311 /* 312 ** Alternatively, smfi_setmlreply can be called if a multi-line SMTP reply 313 ** is needed. 314 */ 315 316 LIBMILTER_API int smfi_setmlreply __P((SMFICTX *, const char *, const char *, ...)); 317 #endif /* _FFR_MULTILINE */ 318 319 /* 320 ** Set the specific reply code to be used in response to the active 321 ** command. If not specified, a generic reply code is used. 322 ** 323 ** SMFICTX *ctx; Opaque context structure 324 ** char *rcode; The three-digit (RFC 821) SMTP reply code to be 325 ** returned, e.g., ``551''. 326 ** char *xcode; The extended (RFC 2034) reply code, e.g., ``5.7.6''. 327 ** char *message; The text part of the SMTP reply. 328 */ 329 330 /* 331 ** The xxfi_eom routine is called at the end of a message (essentially, 332 ** after the final DATA dot). This routine can call some special routines 333 ** to modify the envelope, header, or body of the message before the 334 ** message is enqueued. These routines must not be called from any vendor 335 ** routine other than xxfi_eom. 336 */ 337 338 LIBMILTER_API int smfi_addheader __P((SMFICTX *, char *, char *)); 339 340 /* 341 ** Add a header to the message. This header is not passed to other 342 ** filters. It is not checked for standards compliance; the mail filter 343 ** must ensure that no protocols are violated as a result of adding this 344 ** header. 345 ** 346 ** SMFICTX *ctx; Opaque context structure 347 ** char *headerf; Header field name 348 ** char *headerv; Header field value 349 */ 350 351 LIBMILTER_API int smfi_chgheader __P((SMFICTX *, char *, int, char *)); 352 353 /* 354 ** Change/delete a header in the message. It is not checked for standards 355 ** compliance; the mail filter must ensure that no protocols are violated 356 ** as a result of adding this header. 357 ** 358 ** SMFICTX *ctx; Opaque context structure 359 ** char *headerf; Header field name 360 ** int index; The Nth occurence of header field name 361 ** char *headerv; New header field value (empty for delete header) 362 */ 363 364 LIBMILTER_API int smfi_addrcpt __P((SMFICTX *, char *)); 365 366 /* 367 ** Add a recipient to the envelope 368 ** 369 ** SMFICTX *ctx; Opaque context structure 370 ** char *rcpt; Recipient to be added 371 */ 372 373 LIBMILTER_API int smfi_delrcpt __P((SMFICTX *, char *)); 374 375 #if _FFR_SMFI_PROGRESS 376 /* 377 ** Send a "no-op" up to the MTA to tell it we're still alive, so long 378 ** milter-side operations don't time out. 379 ** 380 ** SMFICTX *ctx; Opaque context structure 381 */ 382 383 LIBMILTER_API int smfi_progress __P((SMFICTX *)); 384 #endif /* _FFR_SMFI_PROGRESS */ 385 386 /* 387 ** Delete a recipient from the envelope 388 ** 389 ** SMFICTX *ctx; Opaque context structure 390 ** char *rcpt; Envelope recipient to be deleted. This should be in 391 ** exactly the form passed to xxfi_envrcpt or the address may 392 ** not be deleted. 393 */ 394 395 LIBMILTER_API int smfi_replacebody __P((SMFICTX *, unsigned char *, int)); 396 397 /* 398 ** Replace the body of the message. This routine may be called multiple 399 ** times if the body is longer than convenient to send in one call. End of 400 ** line should be represented as Carriage-Return/Line Feed. 401 ** 402 ** char *bodyp; Pointer to block of body information to insert 403 ** int bodylen; Length of data pointed at by bodyp 404 */ 405 406 /* 407 ** If the message is aborted (for example, if the SMTP sender sends the 408 ** envelope but then does a QUIT or RSET before the data is sent), 409 ** xxfi_abort is called. This can be used to reset state. 410 */ 411 412 #if _FFR_QUARANTINE 413 /* 414 ** Quarantine an envelope 415 ** 416 ** SMFICTX *ctx; Opaque context structure 417 ** char *reason: explanation 418 */ 419 420 LIBMILTER_API int smfi_quarantine __P((SMFICTX *ctx, char *reason)); 421 #endif /* _FFR_QUARANTINE */ 422 423 /* 424 ** Connection-private data (specific to an SMTP connection) can be 425 ** allocated using the smfi_setpriv routine; routines can access private 426 ** data using smfi_getpriv. 427 */ 428 429 LIBMILTER_API int smfi_setpriv __P((SMFICTX *, void *)); 430 431 /* 432 ** Set the private data pointer 433 ** 434 ** SMFICTX *ctx; Opaque context structure 435 ** void *privatedata; Pointer to private data area 436 */ 437 438 LIBMILTER_API void *smfi_getpriv __P((SMFICTX *)); 439 440 441 #endif /* !_LIBMILTER_MFAPI_H */ 442