1 /* 2 * Copyright (c) 1999-2001 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 8.35 2001/10/09 19:05:24 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/socket.h> 21 # include "libmilter/mfdef.h" 22 23 # define LIBMILTER_API extern 24 25 # include <sys/types.h> 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_setdbg __P((int)); 112 LIBMILTER_API int smfi_settimeout __P((int)); 113 LIBMILTER_API int smfi_setconn __P((char *)); 114 LIBMILTER_API int smfi_stop __P((void)); 115 116 #define SMFI_VERSION 2 /* version number */ 117 118 /* 119 ** What the filter might do -- values to be ORed together for 120 ** smfiDesc.xxfi_flags. 121 */ 122 123 #define SMFIF_NONE 0x00000000L /* no flags */ 124 #define SMFIF_ADDHDRS 0x00000001L /* filter may add headers */ 125 #define SMFIF_CHGBODY 0x00000002L /* filter may replace body */ 126 #define SMFIF_MODBODY SMFIF_CHGBODY /* backwards compatible */ 127 #define SMFIF_ADDRCPT 0x00000004L /* filter may add recipients */ 128 #define SMFIF_DELRCPT 0x00000008L /* filter may delete recipients */ 129 #define SMFIF_CHGHDRS 0x00000010L /* filter may change/delete headers */ 130 #if _FFR_QUARANTINE 131 # define SMFIF_QUARANTINE 0x00000020L /* filter may quarantine envelope */ 132 #endif /* _FFR_QUARANTINE */ 133 134 /* 135 ** Continue processing message/connection. 136 */ 137 138 #define SMFIS_CONTINUE 0 139 140 /* 141 ** Reject the message/connection. 142 ** No further routines will be called for this message 143 ** (or connection, if returned from a connection-oriented routine). 144 */ 145 146 #define SMFIS_REJECT 1 147 148 /* 149 ** Accept the message, 150 ** but silently discard the message. 151 ** No further routines will be called for this message. 152 ** This is only meaningful from message-oriented routines. 153 */ 154 155 #define SMFIS_DISCARD 2 156 157 /* 158 ** Accept the message/connection. 159 ** No further routines will be called for this message 160 ** (or connection, if returned from a connection-oriented routine; 161 ** in this case, it causes all messages on this connection 162 ** to be accepted without filtering). 163 */ 164 165 #define SMFIS_ACCEPT 3 166 167 /* 168 ** Return a temporary failure, i.e., 169 ** the corresponding SMTP command will return a 4xx status code. 170 ** In some cases this may prevent further routines from 171 ** being called on this message or connection, 172 ** although in other cases (e.g., when processing an envelope 173 ** recipient) processing of the message will continue. 174 */ 175 176 #define SMFIS_TEMPFAIL 4 177 178 #if 0 179 /* 180 ** Filter Routine Details 181 */ 182 183 /* connection info filter */ 184 extern sfsistat xxfi_connect __P((SMFICTX *, char *, _SOCK_ADDR *)); 185 186 /* 187 ** xxfi_connect(ctx, hostname, hostaddr) Invoked on each connection 188 ** 189 ** char *hostname; Host domain name, as determined by a reverse lookup 190 ** on the host address. 191 ** _SOCK_ADDR *hostaddr; Host address, as determined by a getpeername 192 ** call on the SMTP socket. 193 */ 194 195 /* SMTP HELO command filter */ 196 extern sfsistat xxfi_helo __P((SMFICTX *, char *)); 197 198 /* 199 ** xxfi_helo(ctx, helohost) Invoked on SMTP HELO/EHLO command 200 ** 201 ** char *helohost; Value passed to HELO/EHLO command, which should be 202 ** the domain name of the sending host (but is, in practice, 203 ** anything the sending host wants to send). 204 */ 205 206 /* envelope sender filter */ 207 extern sfsistat xxfi_envfrom __P((SMFICTX *, char **)); 208 209 /* 210 ** xxfi_envfrom(ctx, argv) Invoked on envelope from 211 ** 212 ** char **argv; Null-terminated SMTP command arguments; 213 ** argv[0] is guaranteed to be the sender address. 214 ** Later arguments are the ESMTP arguments. 215 */ 216 217 /* envelope recipient filter */ 218 extern sfsistat xxfi_envrcpt __P((SMFICTX *, char **)); 219 220 /* 221 ** xxfi_envrcpt(ctx, argv) Invoked on each envelope recipient 222 ** 223 ** char **argv; Null-terminated SMTP command arguments; 224 ** argv[0] is guaranteed to be the recipient address. 225 ** Later arguments are the ESMTP arguments. 226 */ 227 228 /* header filter */ 229 extern sfsistat xxfi_header __P((SMFICTX *, char *, char *)); 230 231 /* 232 ** xxfi_header(ctx, headerf, headerv) Invoked on each message header. The 233 ** content of the header may have folded white space (that is, multiple 234 ** lines with following white space) included. 235 ** 236 ** char *headerf; Header field name 237 ** char *headerv; Header field value 238 */ 239 240 /* end of header */ 241 extern sfsistat xxfi_eoh __P((SMFICTX *)); 242 243 /* 244 ** xxfi_eoh(ctx) Invoked at end of header 245 */ 246 247 /* body block */ 248 extern sfsistat xxfi_body __P((SMFICTX *, unsigned char *, size_t)); 249 250 /* 251 ** xxfi_body(ctx, bodyp, bodylen) Invoked for each body chunk. There may 252 ** be multiple body chunks passed to the filter. End-of-lines are 253 ** represented as received from SMTP (normally Carriage-Return/Line-Feed). 254 ** 255 ** unsigned char *bodyp; Pointer to body data 256 ** size_t bodylen; Length of body data 257 */ 258 259 /* end of message */ 260 extern sfsistat xxfi_eom __P((SMFICTX *)); 261 262 /* 263 ** xxfi_eom(ctx) Invoked at end of message. This routine can perform 264 ** special operations such as modifying the message header, body, or 265 ** envelope. 266 */ 267 268 /* message aborted */ 269 extern sfsistat xxfi_abort __P((SMFICTX *)); 270 271 /* 272 ** xxfi_abort(ctx) Invoked if message is aborted outside of the control of 273 ** the filter, for example, if the SMTP sender issues an RSET command. If 274 ** xxfi_abort is called, xxfi_eom will not be called and vice versa. 275 */ 276 277 /* connection cleanup */ 278 extern sfsistat xxfi_close __P((SMFICTX *)); 279 280 /* 281 ** xxfi_close(ctx) Invoked at end of the connection. This is called on 282 ** close even if the previous mail transaction was aborted. 283 */ 284 #endif /* 0 */ 285 286 /* 287 ** Additional information is passed in to the vendor filter routines using 288 ** symbols. Symbols correspond closely to sendmail macros. The symbols 289 ** defined depend on the context. The value of a symbol is accessed using: 290 */ 291 292 /* Return the value of a symbol. */ 293 LIBMILTER_API char * smfi_getsymval __P((SMFICTX *, char *)); 294 295 /* 296 ** Return the value of a symbol. 297 ** 298 ** SMFICTX *ctx; Opaque context structure 299 ** char *symname; The name of the symbol to access. 300 */ 301 302 /* 303 ** Vendor filter routines that want to pass additional information back to 304 ** the MTA for use in SMTP replies may call smfi_setreply before returning. 305 */ 306 307 LIBMILTER_API int smfi_setreply __P((SMFICTX *, char *, char *, char *)); 308 309 #if _FFR_MULTILINE 310 /* 311 ** Alternatively, smfi_setmlreply can be called if a multi-line SMTP reply 312 ** is needed. 313 */ 314 315 LIBMILTER_API int smfi_setmlreply __P((SMFICTX *, const char *, const char *, ...)); 316 #endif /* _FFR_MULTILINE */ 317 318 /* 319 ** Set the specific reply code to be used in response to the active 320 ** command. If not specified, a generic reply code is used. 321 ** 322 ** SMFICTX *ctx; Opaque context structure 323 ** char *rcode; The three-digit (RFC 821) SMTP reply code to be 324 ** returned, e.g., ``551''. 325 ** char *xcode; The extended (RFC 2034) reply code, e.g., ``5.7.6''. 326 ** char *message; The text part of the SMTP reply. 327 */ 328 329 /* 330 ** The xxfi_eom routine is called at the end of a message (essentially, 331 ** after the final DATA dot). This routine can call some special routines 332 ** to modify the envelope, header, or body of the message before the 333 ** message is enqueued. These routines must not be called from any vendor 334 ** routine other than xxfi_eom. 335 */ 336 337 LIBMILTER_API int smfi_addheader __P((SMFICTX *, char *, char *)); 338 339 /* 340 ** Add a header to the message. This header is not passed to other 341 ** filters. It is not checked for standards compliance; the mail filter 342 ** must ensure that no protocols are violated as a result of adding this 343 ** header. 344 ** 345 ** SMFICTX *ctx; Opaque context structure 346 ** char *headerf; Header field name 347 ** char *headerv; Header field value 348 */ 349 350 LIBMILTER_API int smfi_chgheader __P((SMFICTX *, char *, int, char *)); 351 352 /* 353 ** Change/delete a header in the message. It is not checked for standards 354 ** compliance; the mail filter must ensure that no protocols are violated 355 ** as a result of adding this header. 356 ** 357 ** SMFICTX *ctx; Opaque context structure 358 ** char *headerf; Header field name 359 ** int index; The Nth occurence of header field name 360 ** char *headerv; New header field value (empty for delete header) 361 */ 362 363 LIBMILTER_API int smfi_addrcpt __P((SMFICTX *, char *)); 364 365 /* 366 ** Add a recipient to the envelope 367 ** 368 ** SMFICTX *ctx; Opaque context structure 369 ** char *rcpt; Recipient to be added 370 */ 371 372 LIBMILTER_API int smfi_delrcpt __P((SMFICTX *, char *)); 373 374 /* 375 ** Delete a recipient from the envelope 376 ** 377 ** SMFICTX *ctx; Opaque context structure 378 ** char *rcpt; Envelope recipient to be deleted. This should be in 379 ** exactly the form passed to xxfi_envrcpt or the address may 380 ** not be deleted. 381 */ 382 383 LIBMILTER_API int smfi_replacebody __P((SMFICTX *, unsigned char *, int)); 384 385 /* 386 ** Replace the body of the message. This routine may be called multiple 387 ** times if the body is longer than convenient to send in one call. End of 388 ** line should be represented as Carriage-Return/Line Feed. 389 ** 390 ** char *bodyp; Pointer to block of body information to insert 391 ** int bodylen; Length of data pointed at by bodyp 392 */ 393 394 /* 395 ** If the message is aborted (for example, if the SMTP sender sends the 396 ** envelope but then does a QUIT or RSET before the data is sent), 397 ** xxfi_abort is called. This can be used to reset state. 398 */ 399 400 #if _FFR_QUARANTINE 401 /* 402 ** Quarantine an envelope 403 ** 404 ** SMFICTX *ctx; Opaque context structure 405 ** char *reason: explanation 406 */ 407 408 LIBMILTER_API int smfi_quarantine __P((SMFICTX *ctx, char *reason)); 409 #endif /* _FFR_QUARANTINE */ 410 411 /* 412 ** Connection-private data (specific to an SMTP connection) can be 413 ** allocated using the smfi_setpriv routine; routines can access private 414 ** data using smfi_getpriv. 415 */ 416 417 LIBMILTER_API int smfi_setpriv __P((SMFICTX *, void *)); 418 419 /* 420 ** Set the private data pointer 421 ** 422 ** SMFICTX *ctx; Opaque context structure 423 ** void *privatedata; Pointer to private data area 424 */ 425 426 LIBMILTER_API void *smfi_getpriv __P((SMFICTX *)); 427 428 429 #endif /* !_LIBMILTER_MFAPI_H */ 430