xref: /freebsd/contrib/sendmail/libmilter/engine.c (revision d640d2e29d6b79c7b50146bfd39b4b91417c2fbc)
1 /*
2  *  Copyright (c) 1999-2004, 2006 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 
11 #include <sm/gen.h>
12 SM_RCSID("@(#)$Id: engine.c,v 8.157 2007/03/26 18:10:04 ca Exp $")
13 
14 #include "libmilter.h"
15 
16 #if NETINET || NETINET6
17 # include <arpa/inet.h>
18 #endif /* NETINET || NETINET6 */
19 
20 /* generic argument for functions in the command table */
21 struct arg_struct
22 {
23 	size_t		a_len;		/* length of buffer */
24 	char		*a_buf;		/* argument string */
25 	int		a_idx;		/* index for macro array */
26 	SMFICTX_PTR	a_ctx;		/* context */
27 };
28 
29 typedef struct arg_struct genarg;
30 
31 /* structure for commands received from MTA */
32 struct cmdfct_t
33 {
34 	char	cm_cmd;				/* command */
35 	int	cm_argt;			/* type of arguments expected */
36 	int	cm_next;			/* next state */
37 	int	cm_todo;			/* what to do next */
38 	int	cm_macros;			/* index for macros */
39 	int	(*cm_fct) __P((genarg *));	/* function to execute */
40 };
41 
42 typedef struct cmdfct_t cmdfct;
43 
44 /* possible values for cm_argt */
45 #define	CM_ARG0	0	/* no args */
46 #define	CM_ARG1	1	/* one arg (string) */
47 #define	CM_ARG2	2	/* two args (strings) */
48 #define	CM_ARGA	4	/* one string and _SOCK_ADDR */
49 #define	CM_ARGO	5	/* two integers */
50 #define	CM_ARGV	8	/* \0 separated list of args, NULL-terminated */
51 #define	CM_ARGN	9	/* \0 separated list of args (strings) */
52 
53 /* possible values for cm_todo */
54 #define	CT_CONT		0x0000	/* continue reading commands */
55 #define	CT_IGNO		0x0001	/* continue even when error  */
56 
57 /* not needed right now, done via return code instead */
58 #define	CT_KEEP		0x0004	/* keep buffer (contains symbols) */
59 #define	CT_END		0x0008	/* last command of session, stop replying */
60 
61 /* index in macro array: macros only for these commands */
62 #define	CI_NONE		(-1)
63 #define	CI_CONN		0
64 #define	CI_HELO		1
65 #define	CI_MAIL		2
66 #define CI_RCPT		3
67 #define CI_DATA		4
68 #define CI_EOM		5
69 #define CI_EOH		6
70 #define CI_LAST		CI_EOH
71 #if CI_LAST < CI_DATA
72 ERROR: do not compile with CI_LAST < CI_DATA
73 #endif
74 #if CI_LAST < CI_EOM
75 ERROR: do not compile with CI_LAST < CI_EOM
76 #endif
77 #if CI_LAST < CI_EOH
78 ERROR: do not compile with CI_LAST < CI_EOH
79 #endif
80 #if CI_LAST < CI_ENVRCPT
81 ERROR: do not compile with CI_LAST < CI_ENVRCPT
82 #endif
83 #if CI_LAST < CI_ENVFROM
84 ERROR: do not compile with CI_LAST < CI_ENVFROM
85 #endif
86 #if CI_LAST < CI_HELO
87 ERROR: do not compile with CI_LAST < CI_HELO
88 #endif
89 #if CI_LAST < CI_CONNECT
90 ERROR: do not compile with CI_LAST < CI_CONNECT
91 #endif
92 #if CI_LAST >= MAX_MACROS_ENTRIES
93 ERROR: do not compile with CI_LAST >= MAX_MACROS_ENTRIES
94 #endif
95 
96 /* function prototypes */
97 static int	st_abortfct __P((genarg *));
98 static int	st_macros __P((genarg *));
99 static int	st_optionneg __P((genarg *));
100 static int	st_bodychunk __P((genarg *));
101 static int	st_connectinfo __P((genarg *));
102 static int	st_bodyend __P((genarg *));
103 static int	st_helo __P((genarg *));
104 static int	st_header __P((genarg *));
105 static int	st_sender __P((genarg *));
106 static int	st_rcpt __P((genarg *));
107 static int	st_unknown __P((genarg *));
108 static int	st_data __P((genarg *));
109 static int	st_eoh __P((genarg *));
110 static int	st_quit __P((genarg *));
111 static int	sendreply __P((sfsistat, socket_t, struct timeval *, SMFICTX_PTR));
112 static void	fix_stm __P((SMFICTX_PTR));
113 static bool	trans_ok __P((int, int));
114 static char	**dec_argv __P((char *, size_t));
115 static int	dec_arg2 __P((char *, size_t, char **, char **));
116 
117 #if _FFR_WORKERS_POOL
118 static bool     mi_rd_socket_ready __P((int));
119 #endif /* _FFR_WORKERS_POOL */
120 
121 /* states */
122 #define ST_NONE	(-1)
123 #define ST_INIT	0	/* initial state */
124 #define ST_OPTS	1	/* option negotiation */
125 #define ST_CONN	2	/* connection info */
126 #define ST_HELO	3	/* helo */
127 #define ST_MAIL	4	/* mail from */
128 #define ST_RCPT	5	/* rcpt to */
129 #define ST_DATA	6	/* data */
130 #define ST_HDRS	7	/* headers */
131 #define ST_EOHS	8	/* end of headers */
132 #define ST_BODY	9	/* body */
133 #define ST_ENDM	10	/* end of message */
134 #define ST_QUIT	11	/* quit */
135 #define ST_ABRT	12	/* abort */
136 #define ST_UNKN 13	/* unknown SMTP command */
137 #define ST_Q_NC	14	/* quit, new connection follows */
138 #define ST_LAST	ST_Q_NC	/* last valid state */
139 #define ST_SKIP	16	/* not a state but required for the state table */
140 
141 /* in a mail transaction? must be before eom according to spec. */
142 #define ST_IN_MAIL(st)	((st) >= ST_MAIL && (st) < ST_ENDM)
143 
144 /*
145 **  set of next states
146 **  each state (ST_*) corresponds to bit in an int value (1 << state)
147 **  each state has a set of allowed transitions ('or' of bits of states)
148 **  so a state transition is valid if the mask of the next state
149 **  is set in the NX_* value
150 **  this function is coded in trans_ok(), see below.
151 */
152 
153 #define MI_MASK(x)	(0x0001 << (x))	/* generate a bit "mask" for a state */
154 #define NX_INIT	(MI_MASK(ST_OPTS))
155 #define NX_OPTS	(MI_MASK(ST_CONN) | MI_MASK(ST_UNKN))
156 #define NX_CONN	(MI_MASK(ST_HELO) | MI_MASK(ST_MAIL) | MI_MASK(ST_UNKN))
157 #define NX_HELO	(MI_MASK(ST_HELO) | MI_MASK(ST_MAIL) | MI_MASK(ST_UNKN))
158 #define NX_MAIL	(MI_MASK(ST_RCPT) | MI_MASK(ST_ABRT) | MI_MASK(ST_UNKN))
159 #define NX_RCPT	(MI_MASK(ST_HDRS) | MI_MASK(ST_EOHS) | MI_MASK(ST_DATA) | \
160 		 MI_MASK(ST_BODY) | MI_MASK(ST_ENDM) | \
161 		 MI_MASK(ST_RCPT) | MI_MASK(ST_ABRT) | MI_MASK(ST_UNKN))
162 #define NX_DATA	(MI_MASK(ST_EOHS) | MI_MASK(ST_HDRS) | MI_MASK(ST_ABRT))
163 #define NX_HDRS	(MI_MASK(ST_EOHS) | MI_MASK(ST_HDRS) | MI_MASK(ST_ABRT))
164 #define NX_EOHS	(MI_MASK(ST_BODY) | MI_MASK(ST_ENDM) | MI_MASK(ST_ABRT))
165 #define NX_BODY	(MI_MASK(ST_ENDM) | MI_MASK(ST_BODY) | MI_MASK(ST_ABRT))
166 #define NX_ENDM	(MI_MASK(ST_QUIT) | MI_MASK(ST_MAIL) | MI_MASK(ST_UNKN) | \
167 		MI_MASK(ST_Q_NC))
168 #define NX_QUIT	0
169 #define NX_ABRT	0
170 #define NX_UNKN (MI_MASK(ST_HELO) | MI_MASK(ST_MAIL) | \
171 		 MI_MASK(ST_RCPT) | MI_MASK(ST_ABRT) | \
172 		 MI_MASK(ST_DATA) | \
173 		 MI_MASK(ST_BODY) | MI_MASK(ST_UNKN) | \
174 		 MI_MASK(ST_ABRT) | MI_MASK(ST_QUIT) | MI_MASK(ST_Q_NC))
175 #define NX_Q_NC	(MI_MASK(ST_CONN) | MI_MASK(ST_UNKN))
176 #define NX_SKIP MI_MASK(ST_SKIP)
177 
178 static int next_states[] =
179 {
180 	  NX_INIT
181 	, NX_OPTS
182 	, NX_CONN
183 	, NX_HELO
184 	, NX_MAIL
185 	, NX_RCPT
186 	, NX_DATA
187 	, NX_HDRS
188 	, NX_EOHS
189 	, NX_BODY
190 	, NX_ENDM
191 	, NX_QUIT
192 	, NX_ABRT
193 	, NX_UNKN
194 	, NX_Q_NC
195 };
196 
197 #define SIZE_NEXT_STATES	(sizeof(next_states) / sizeof(next_states[0]))
198 
199 /* commands received by milter */
200 static cmdfct cmds[] =
201 {
202   {SMFIC_ABORT,	CM_ARG0, ST_ABRT,  CT_CONT,	CI_NONE, st_abortfct	}
203 , {SMFIC_MACRO,	CM_ARGV, ST_NONE,  CT_KEEP,	CI_NONE, st_macros	}
204 , {SMFIC_BODY,	CM_ARG1, ST_BODY,  CT_CONT,	CI_NONE, st_bodychunk	}
205 , {SMFIC_CONNECT, CM_ARG2, ST_CONN,  CT_CONT,	CI_CONN, st_connectinfo	}
206 , {SMFIC_BODYEOB, CM_ARG1, ST_ENDM,  CT_CONT,	CI_EOM,  st_bodyend	}
207 , {SMFIC_HELO,	CM_ARG1, ST_HELO,  CT_CONT,	CI_HELO, st_helo	}
208 , {SMFIC_HEADER, CM_ARG2, ST_HDRS,  CT_CONT,	CI_NONE, st_header	}
209 , {SMFIC_MAIL,	CM_ARGV, ST_MAIL,  CT_CONT,	CI_MAIL, st_sender	}
210 , {SMFIC_OPTNEG, CM_ARGO, ST_OPTS,  CT_CONT,	CI_NONE, st_optionneg	}
211 , {SMFIC_EOH,	CM_ARG0, ST_EOHS,  CT_CONT,	CI_EOH,  st_eoh		}
212 , {SMFIC_QUIT,	CM_ARG0, ST_QUIT,  CT_END,	CI_NONE, st_quit	}
213 , {SMFIC_DATA,	CM_ARG0, ST_DATA,  CT_CONT,	CI_DATA, st_data	}
214 , {SMFIC_RCPT,	CM_ARGV, ST_RCPT,  CT_IGNO,	CI_RCPT, st_rcpt	}
215 , {SMFIC_UNKNOWN, CM_ARG1, ST_UNKN,  CT_IGNO,	CI_NONE, st_unknown	}
216 , {SMFIC_QUIT_NC, CM_ARG0, ST_Q_NC,  CT_CONT,	CI_NONE, st_quit	}
217 };
218 
219 /*
220 **  Additional (internal) reply codes;
221 **  must be coordinated wit libmilter/mfapi.h
222 */
223 
224 #define _SMFIS_KEEP	20
225 #define _SMFIS_ABORT	21
226 #define _SMFIS_OPTIONS	22
227 #define _SMFIS_NOREPLY	SMFIS_NOREPLY
228 #define _SMFIS_FAIL	(-1)
229 #define _SMFIS_NONE	(-2)
230 
231 /*
232 **  MI_ENGINE -- receive commands and process them
233 **
234 **	Parameters:
235 **		ctx -- context structure
236 **
237 **	Returns:
238 **		MI_FAILURE/MI_SUCCESS
239 */
240 
241 int
242 mi_engine(ctx)
243 	SMFICTX_PTR ctx;
244 {
245 	size_t len;
246 	int i;
247 	socket_t sd;
248 	int ret = MI_SUCCESS;
249 	int ncmds = sizeof(cmds) / sizeof(cmdfct);
250 	int curstate = ST_INIT;
251 	int newstate;
252 	bool call_abort;
253 	sfsistat r;
254 	char cmd;
255 	char *buf = NULL;
256 	genarg arg;
257 	struct timeval timeout;
258 	int (*f) __P((genarg *));
259 	sfsistat (*fi_abort) __P((SMFICTX *));
260 	sfsistat (*fi_close) __P((SMFICTX *));
261 
262 	arg.a_ctx = ctx;
263 	sd = ctx->ctx_sd;
264 	fi_abort = ctx->ctx_smfi->xxfi_abort;
265 #if _FFR_WORKERS_POOL
266 	curstate = ctx->ctx_state;
267 	if (curstate == ST_INIT)
268 	{
269 		mi_clr_macros(ctx, 0);
270 		fix_stm(ctx);
271 	}
272 #else   /* _FFR_WORKERS_POOL */
273 	mi_clr_macros(ctx, 0);
274 	fix_stm(ctx);
275 #endif  /* _FFR_WORKERS_POOL */
276 	r = _SMFIS_NONE;
277 	do
278 	{
279 		/* call abort only if in a mail transaction */
280 		call_abort = ST_IN_MAIL(curstate);
281 		timeout.tv_sec = ctx->ctx_timeout;
282 		timeout.tv_usec = 0;
283 		if (mi_stop() == MILTER_ABRT)
284 		{
285 			if (ctx->ctx_dbg > 3)
286 				sm_dprintf("[%ld] milter_abort\n",
287 					(long) ctx->ctx_id);
288 			ret = MI_FAILURE;
289 			break;
290 		}
291 
292 		/*
293 		**  Notice: buf is allocated by mi_rd_cmd() and it will
294 		**  usually be free()d after it has been used in f().
295 		**  However, if the function returns _SMFIS_KEEP then buf
296 		**  contains macros and will not be free()d.
297 		**  Hence r must be set to _SMFIS_NONE if a new buf is
298 		**  allocated to avoid problem with housekeeping, esp.
299 		**  if the code "break"s out of the loop.
300 		*/
301 
302 #if _FFR_WORKERS_POOL
303 		/* Is the socket ready to be read ??? */
304 		if (!mi_rd_socket_ready(sd))
305 		{
306 			ret = MI_CONTINUE;
307 			break;
308 		}
309 #endif  /* _FFR_WORKERS_POOL */
310 
311 		r = _SMFIS_NONE;
312 		if ((buf = mi_rd_cmd(sd, &timeout, &cmd, &len,
313 				     ctx->ctx_smfi->xxfi_name)) == NULL &&
314 		    cmd < SMFIC_VALIDCMD)
315 		{
316 			if (ctx->ctx_dbg > 5)
317 				sm_dprintf("[%ld] mi_engine: mi_rd_cmd error (%x)\n",
318 					(long) ctx->ctx_id, (int) cmd);
319 
320 			/*
321 			**  eof is currently treated as failure ->
322 			**  abort() instead of close(), otherwise use:
323 			**  if (cmd != SMFIC_EOF)
324 			*/
325 
326 			ret = MI_FAILURE;
327 			break;
328 		}
329 		if (ctx->ctx_dbg > 4)
330 			sm_dprintf("[%ld] got cmd '%c' len %d\n",
331 				(long) ctx->ctx_id, cmd, (int) len);
332 		for (i = 0; i < ncmds; i++)
333 		{
334 			if (cmd == cmds[i].cm_cmd)
335 				break;
336 		}
337 		if (i >= ncmds)
338 		{
339 			/* unknown command */
340 			if (ctx->ctx_dbg > 1)
341 				sm_dprintf("[%ld] cmd '%c' unknown\n",
342 					(long) ctx->ctx_id, cmd);
343 			ret = MI_FAILURE;
344 			break;
345 		}
346 		if ((f = cmds[i].cm_fct) == NULL)
347 		{
348 			/* stop for now */
349 			if (ctx->ctx_dbg > 1)
350 				sm_dprintf("[%ld] cmd '%c' not impl\n",
351 					(long) ctx->ctx_id, cmd);
352 			ret = MI_FAILURE;
353 			break;
354 		}
355 
356 		/* is new state ok? */
357 		newstate = cmds[i].cm_next;
358 		if (ctx->ctx_dbg > 5)
359 			sm_dprintf("[%ld] cur %x new %x nextmask %x\n",
360 				(long) ctx->ctx_id,
361 				curstate, newstate, next_states[curstate]);
362 
363 		if (newstate != ST_NONE && !trans_ok(curstate, newstate))
364 		{
365 			if (ctx->ctx_dbg > 1)
366 				sm_dprintf("[%ld] abort: cur %d (%x) new %d (%x) next %x\n",
367 					(long) ctx->ctx_id,
368 					curstate, MI_MASK(curstate),
369 					newstate, MI_MASK(newstate),
370 					next_states[curstate]);
371 
372 			/* call abort only if in a mail transaction */
373 			if (fi_abort != NULL && call_abort)
374 				(void) (*fi_abort)(ctx);
375 
376 			/*
377 			**  try to reach the new state from HELO
378 			**  if it can't be reached, ignore the command.
379 			*/
380 
381 			curstate = ST_HELO;
382 			if (!trans_ok(curstate, newstate))
383 			{
384 				if (buf != NULL)
385 				{
386 					free(buf);
387 					buf = NULL;
388 				}
389 				continue;
390 			}
391 		}
392 		arg.a_len = len;
393 		arg.a_buf = buf;
394 		if (newstate != ST_NONE)
395 		{
396 			curstate = newstate;
397 			ctx->ctx_state = curstate;
398 		}
399 		arg.a_idx = cmds[i].cm_macros;
400 		call_abort = ST_IN_MAIL(curstate);
401 
402 		/* call function to deal with command */
403 		MI_MONITOR_BEGIN(ctx, cmd);
404 		r = (*f)(&arg);
405 		MI_MONITOR_END(ctx, cmd);
406 		if (r != _SMFIS_KEEP && buf != NULL)
407 		{
408 			free(buf);
409 			buf = NULL;
410 		}
411 		if (sendreply(r, sd, &timeout, ctx) != MI_SUCCESS)
412 		{
413 			ret = MI_FAILURE;
414 			break;
415 		}
416 
417 		if (r == SMFIS_ACCEPT)
418 		{
419 			/* accept mail, no further actions taken */
420 			curstate = ST_HELO;
421 		}
422 		else if (r == SMFIS_REJECT || r == SMFIS_DISCARD ||
423 			 r ==  SMFIS_TEMPFAIL)
424 		{
425 			/*
426 			**  further actions depend on current state
427 			**  if the IGNO bit is set: "ignore" the error,
428 			**  i.e., stay in the current state
429 			*/
430 			if (!bitset(CT_IGNO, cmds[i].cm_todo))
431 				curstate = ST_HELO;
432 		}
433 		else if (r == _SMFIS_ABORT)
434 		{
435 			if (ctx->ctx_dbg > 5)
436 				sm_dprintf("[%ld] function returned abort\n",
437 					(long) ctx->ctx_id);
438 			ret = MI_FAILURE;
439 			break;
440 		}
441 	} while (!bitset(CT_END, cmds[i].cm_todo));
442 
443 	ctx->ctx_state = curstate;
444 
445 	if (ret == MI_FAILURE)
446 	{
447 		/* call abort only if in a mail transaction */
448 		if (fi_abort != NULL && call_abort)
449 			(void) (*fi_abort)(ctx);
450 	}
451 
452 	/* has close been called? */
453 	if (ctx->ctx_state != ST_QUIT
454 #if _FFR_WORKERS_POOL
455 	   && ret != MI_CONTINUE
456 #endif /* _FFR_WORKERS_POOL */
457 	   )
458 	{
459 		if ((fi_close = ctx->ctx_smfi->xxfi_close) != NULL)
460 			(void) (*fi_close)(ctx);
461 	}
462 	if (r != _SMFIS_KEEP && buf != NULL)
463 		free(buf);
464 #if !_FFR_WORKERS_POOL
465 	mi_clr_macros(ctx, 0);
466 #endif /* _FFR_WORKERS_POOL */
467 	return ret;
468 }
469 
470 static size_t milter_addsymlist __P((SMFICTX_PTR, char *, char **));
471 
472 static size_t
473 milter_addsymlist(ctx, buf, newbuf)
474 	SMFICTX_PTR ctx;
475 	char *buf;
476 	char **newbuf;
477 {
478 	size_t len;
479 	int i;
480 	mi_int32 v;
481 	char *buffer;
482 
483 	SM_ASSERT(ctx != NULL);
484 	SM_ASSERT(buf != NULL);
485 	SM_ASSERT(newbuf != NULL);
486 	len = 0;
487 	for (i = 0; i < MAX_MACROS_ENTRIES; i++)
488 	{
489 		if (ctx->ctx_mac_list[i] != NULL)
490 		{
491 			len += strlen(ctx->ctx_mac_list[i]) + 1 +
492 				MILTER_LEN_BYTES;
493 		}
494 	}
495 	if (len > 0)
496 	{
497 		size_t offset;
498 
499 		SM_ASSERT(len + MILTER_OPTLEN > len);
500 		len += MILTER_OPTLEN;
501 		buffer = malloc(len);
502 		if (buffer != NULL)
503 		{
504 			(void) memcpy(buffer, buf, MILTER_OPTLEN);
505 			offset = MILTER_OPTLEN;
506 			for (i = 0; i < MAX_MACROS_ENTRIES; i++)
507 			{
508 				size_t l;
509 
510 				if (ctx->ctx_mac_list[i] == NULL)
511 					continue;
512 
513 				SM_ASSERT(offset + MILTER_LEN_BYTES < len);
514 				v = htonl(i);
515 				(void) memcpy(buffer + offset, (void *) &v,
516 						MILTER_LEN_BYTES);
517 				offset += MILTER_LEN_BYTES;
518 				l = strlen(ctx->ctx_mac_list[i]) + 1;
519 				SM_ASSERT(offset + l <= len);
520 				(void) memcpy(buffer + offset,
521 						ctx->ctx_mac_list[i], l);
522 				offset += l;
523 			}
524 		}
525 		else
526 		{
527 			/* oops ... */
528 		}
529 	}
530 	else
531 	{
532 		len = MILTER_OPTLEN;
533 		buffer = buf;
534 	}
535 	*newbuf = buffer;
536 	return len;
537 }
538 
539 /*
540 **  GET_NR_BIT -- get "no reply" bit matching state
541 **
542 **	Parameters:
543 **		state -- current protocol stage
544 **
545 **	Returns:
546 **		0: no matching bit
547 **		>0: the matching "no reply" bit
548 */
549 
550 static unsigned long get_nr_bit __P((int));
551 
552 static unsigned long
553 get_nr_bit(state)
554 	int state;
555 {
556 	unsigned long bit;
557 
558 	switch (state)
559 	{
560 	  case ST_CONN:
561 		bit = SMFIP_NR_CONN;
562 		break;
563 	  case ST_HELO:
564 		bit = SMFIP_NR_HELO;
565 		break;
566 	  case ST_MAIL:
567 		bit = SMFIP_NR_MAIL;
568 		break;
569 	  case ST_RCPT:
570 		bit = SMFIP_NR_RCPT;
571 		break;
572 	  case ST_DATA:
573 		bit = SMFIP_NR_DATA;
574 		break;
575 	  case ST_UNKN:
576 		bit = SMFIP_NR_UNKN;
577 		break;
578 	  case ST_HDRS:
579 		bit = SMFIP_NR_HDR;
580 		break;
581 	  case ST_EOHS:
582 		bit = SMFIP_NR_EOH;
583 		break;
584 	  case ST_BODY:
585 		bit = SMFIP_NR_BODY;
586 		break;
587 	  default:
588 		bit = 0;
589 		break;
590 	}
591 	return bit;
592 }
593 
594 /*
595 **  SENDREPLY -- send a reply to the MTA
596 **
597 **	Parameters:
598 **		r -- reply code
599 **		sd -- socket descriptor
600 **		timeout_ptr -- (ptr to) timeout to use for sending
601 **		ctx -- context structure
602 **
603 **	Returns:
604 **		MI_SUCCESS/MI_FAILURE
605 */
606 
607 static int
608 sendreply(r, sd, timeout_ptr, ctx)
609 	sfsistat r;
610 	socket_t sd;
611 	struct timeval *timeout_ptr;
612 	SMFICTX_PTR ctx;
613 {
614 	int ret;
615 	unsigned long bit;
616 
617 	ret = MI_SUCCESS;
618 
619 	bit = get_nr_bit(ctx->ctx_state);
620 	if (bit != 0 && (ctx->ctx_pflags & bit) != 0 && r != SMFIS_NOREPLY)
621 	{
622 		if (r >= SMFIS_CONTINUE && r < _SMFIS_KEEP)
623 		{
624 			/* milter said it wouldn't reply, but it lied... */
625 			smi_log(SMI_LOG_ERR,
626 				"%s: milter claimed not to reply in state %d but did anyway %d\n",
627 				ctx->ctx_smfi->xxfi_name,
628 				ctx->ctx_state, r);
629 
630 		}
631 
632 		/*
633 		**  Force specified behavior, otherwise libmilter
634 		**  and MTA will fail to communicate properly.
635 		*/
636 
637 		switch (r)
638 		{
639 		  case SMFIS_CONTINUE:
640 		  case SMFIS_TEMPFAIL:
641 		  case SMFIS_REJECT:
642 		  case SMFIS_DISCARD:
643 		  case SMFIS_ACCEPT:
644 		  case SMFIS_SKIP:
645 		  case _SMFIS_OPTIONS:
646 			r = SMFIS_NOREPLY;
647 			break;
648 		}
649 	}
650 
651 	switch (r)
652 	{
653 	  case SMFIS_CONTINUE:
654 		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_CONTINUE, NULL, 0);
655 		break;
656 	  case SMFIS_TEMPFAIL:
657 	  case SMFIS_REJECT:
658 		if (ctx->ctx_reply != NULL &&
659 		    ((r == SMFIS_TEMPFAIL && *ctx->ctx_reply == '4') ||
660 		     (r == SMFIS_REJECT && *ctx->ctx_reply == '5')))
661 		{
662 			ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_REPLYCODE,
663 					ctx->ctx_reply,
664 					strlen(ctx->ctx_reply) + 1);
665 			free(ctx->ctx_reply);
666 			ctx->ctx_reply = NULL;
667 		}
668 		else
669 		{
670 			ret = mi_wr_cmd(sd, timeout_ptr, r == SMFIS_REJECT ?
671 					SMFIR_REJECT : SMFIR_TEMPFAIL, NULL, 0);
672 		}
673 		break;
674 	  case SMFIS_DISCARD:
675 		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_DISCARD, NULL, 0);
676 		break;
677 	  case SMFIS_ACCEPT:
678 		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_ACCEPT, NULL, 0);
679 		break;
680 	  case SMFIS_SKIP:
681 		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_SKIP, NULL, 0);
682 		break;
683 	  case _SMFIS_OPTIONS:
684 		{
685 			mi_int32 v;
686 			size_t len;
687 			char *buffer;
688 			char buf[MILTER_OPTLEN];
689 
690 			v = htonl(ctx->ctx_prot_vers2mta);
691 			(void) memcpy(&(buf[0]), (void *) &v,
692 				      MILTER_LEN_BYTES);
693 			v = htonl(ctx->ctx_aflags);
694 			(void) memcpy(&(buf[MILTER_LEN_BYTES]), (void *) &v,
695 				      MILTER_LEN_BYTES);
696 			v = htonl(ctx->ctx_pflags2mta);
697 			(void) memcpy(&(buf[MILTER_LEN_BYTES * 2]),
698 				      (void *) &v, MILTER_LEN_BYTES);
699 			len = milter_addsymlist(ctx, buf, &buffer);
700 			if (buffer != NULL)
701 				ret = mi_wr_cmd(sd, timeout_ptr, SMFIC_OPTNEG,
702 						buffer, len);
703 			else
704 				ret = MI_FAILURE;
705 		}
706 		break;
707 	  case SMFIS_NOREPLY:
708 		if (bit != 0 &&
709 		    (ctx->ctx_pflags & bit) != 0 &&
710 		    (ctx->ctx_mta_pflags & bit) == 0)
711 		{
712 			/*
713 			**  milter doesn't want to send a reply,
714 			**  but the MTA doesn't have that feature: fake it.
715 			*/
716 
717 			ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_CONTINUE, NULL,
718 					0);
719 		}
720 		break;
721 	  default:	/* don't send a reply */
722 		break;
723 	}
724 	return ret;
725 }
726 
727 /*
728 **  CLR_MACROS -- clear set of macros starting from a given index
729 **
730 **	Parameters:
731 **		ctx -- context structure
732 **		m -- index from which to clear all macros
733 **
734 **	Returns:
735 **		None.
736 */
737 
738 void
739 mi_clr_macros(ctx, m)
740 	SMFICTX_PTR ctx;
741 	int m;
742 {
743 	int i;
744 
745 	for (i = m; i < MAX_MACROS_ENTRIES; i++)
746 	{
747 		if (ctx->ctx_mac_ptr[i] != NULL)
748 		{
749 			free(ctx->ctx_mac_ptr[i]);
750 			ctx->ctx_mac_ptr[i] = NULL;
751 		}
752 		if (ctx->ctx_mac_buf[i] != NULL)
753 		{
754 			free(ctx->ctx_mac_buf[i]);
755 			ctx->ctx_mac_buf[i] = NULL;
756 		}
757 	}
758 }
759 
760 /*
761 **  ST_OPTIONNEG -- negotiate options
762 **
763 **	Parameters:
764 **		g -- generic argument structure
765 **
766 **	Returns:
767 **		abort/send options/continue
768 */
769 
770 static int
771 st_optionneg(g)
772 	genarg *g;
773 {
774 	mi_int32 i, v, fake_pflags;
775 	SMFICTX_PTR ctx;
776 	int (*fi_negotiate) __P((SMFICTX *,
777 					unsigned long, unsigned long,
778 					unsigned long, unsigned long,
779 					unsigned long *, unsigned long *,
780 					unsigned long *, unsigned long *));
781 
782 	if (g == NULL || g->a_ctx->ctx_smfi == NULL)
783 		return SMFIS_CONTINUE;
784 	ctx = g->a_ctx;
785 	mi_clr_macros(ctx, g->a_idx + 1);
786 	ctx->ctx_prot_vers = SMFI_PROT_VERSION;
787 
788 	/* check for minimum length */
789 	if (g->a_len < MILTER_OPTLEN)
790 	{
791 		smi_log(SMI_LOG_ERR,
792 			"%s: st_optionneg[%ld]: len too short %d < %d",
793 			ctx->ctx_smfi->xxfi_name,
794 			(long) ctx->ctx_id, (int) g->a_len,
795 			MILTER_OPTLEN);
796 		return _SMFIS_ABORT;
797 	}
798 
799 	/* protocol version */
800 	(void) memcpy((void *) &i, (void *) &(g->a_buf[0]), MILTER_LEN_BYTES);
801 	v = ntohl(i);
802 
803 #define SMFI_PROT_VERSION_MIN	2
804 
805 	/* check for minimum version */
806 	if (v < SMFI_PROT_VERSION_MIN)
807 	{
808 		smi_log(SMI_LOG_ERR,
809 			"%s: st_optionneg[%ld]: protocol version too old %d < %d",
810 			ctx->ctx_smfi->xxfi_name,
811 			(long) ctx->ctx_id, v, SMFI_PROT_VERSION_MIN);
812 		return _SMFIS_ABORT;
813 	}
814 	ctx->ctx_mta_prot_vers = v;
815 	if (ctx->ctx_prot_vers < ctx->ctx_mta_prot_vers)
816 		ctx->ctx_prot_vers2mta = ctx->ctx_prot_vers;
817 	else
818 		ctx->ctx_prot_vers2mta = ctx->ctx_mta_prot_vers;
819 
820 	(void) memcpy((void *) &i, (void *) &(g->a_buf[MILTER_LEN_BYTES]),
821 		      MILTER_LEN_BYTES);
822 	v = ntohl(i);
823 
824 	/* no flags? set to default value for V1 actions */
825 	if (v == 0)
826 		v = SMFI_V1_ACTS;
827 	ctx->ctx_mta_aflags = v;	/* MTA action flags */
828 
829 	(void) memcpy((void *) &i, (void *) &(g->a_buf[MILTER_LEN_BYTES * 2]),
830 		      MILTER_LEN_BYTES);
831 	v = ntohl(i);
832 
833 	/* no flags? set to default value for V1 protocol */
834 	if (v == 0)
835 		v = SMFI_V1_PROT;
836 	ctx->ctx_mta_pflags = v;	/* MTA protocol flags */
837 
838 	/*
839 	**  Copy flags from milter struct into libmilter context;
840 	**  this variable will be used later on to check whether
841 	**  the MTA "actions" can fulfill the milter requirements,
842 	**  but it may be overwritten by the negotiate callback.
843 	*/
844 
845 	ctx->ctx_aflags = ctx->ctx_smfi->xxfi_flags;
846 	fake_pflags = SMFIP_NR_CONN
847 			|SMFIP_NR_HELO
848 			|SMFIP_NR_MAIL
849 			|SMFIP_NR_RCPT
850 			|SMFIP_NR_DATA
851 			|SMFIP_NR_UNKN
852 			|SMFIP_NR_HDR
853 			|SMFIP_NR_EOH
854 			|SMFIP_NR_BODY
855 			;
856 
857 	if (g->a_ctx->ctx_smfi != NULL &&
858 	    (fi_negotiate = g->a_ctx->ctx_smfi->xxfi_negotiate) != NULL)
859 	{
860 		int r;
861 		unsigned long m_aflags, m_pflags, m_f2, m_f3;
862 
863 		/*
864 		**  let milter decide whether the features offered by the
865 		**  MTA are "good enough".
866 		**  Notes:
867 		**  - libmilter can "fake" some features (e.g., SMFIP_NR_HDR)
868 		**  - m_f2, m_f3 are for future extensions
869 		*/
870 
871 		m_f2 = m_f3 = 0;
872 		m_aflags = ctx->ctx_mta_aflags;
873 		m_pflags = ctx->ctx_pflags;
874 		if ((SMFIP_SKIP & ctx->ctx_mta_pflags) != 0)
875 			m_pflags |= SMFIP_SKIP;
876 		r = fi_negotiate(g->a_ctx,
877 				ctx->ctx_mta_aflags,
878 				ctx->ctx_mta_pflags|fake_pflags,
879 				0, 0,
880 				&m_aflags, &m_pflags, &m_f2, &m_f3);
881 
882 		/*
883 		**  Types of protocol flags (pflags):
884 		**  1. do NOT send protocol step X
885 		**  2. MTA can do/understand something extra (SKIP,
886 		**	send unknown RCPTs)
887 		**  3. MTA can deal with "no reply" for various protocol steps
888 		**  Note: this mean that it isn't possible to simply set all
889 		**	flags to get "everything":
890 		**	setting a flag of type 1 turns off a step
891 		**		(it should be the other way around:
892 		**		a flag means a protocol step can be sent)
893 		**	setting a flag of type 3 requires that milter
894 		**	never sends a reply for the corresponding step.
895 		**  Summary: the "negation" of protocol flags is causing
896 		**	problems, but at least for type 3 there is no simple
897 		**	solution.
898 		**
899 		**  What should "all options" mean?
900 		**  send all protocol steps _except_ those for which there is
901 		**	no callback (currently registered in ctx_pflags)
902 		**  expect SKIP as return code?		Yes
903 		**  send unknown RCPTs?			No,
904 		**				must be explicitly requested?
905 		**  "no reply" for some protocol steps?	No,
906 		**				must be explicitly requested.
907 		*/
908 
909 		if (SMFIS_ALL_OPTS == r)
910 		{
911 			ctx->ctx_aflags = ctx->ctx_mta_aflags;
912 			ctx->ctx_pflags2mta = ctx->ctx_pflags;
913 			if ((SMFIP_SKIP & ctx->ctx_mta_pflags) != 0)
914 				ctx->ctx_pflags2mta |= SMFIP_SKIP;
915 		}
916 		else if (r != SMFIS_CONTINUE)
917 		{
918 			smi_log(SMI_LOG_ERR,
919 				"%s: st_optionneg[%ld]: xxfi_negotiate returned %d (protocol options=0x%lx, actions=0x%lx)",
920 				ctx->ctx_smfi->xxfi_name,
921 				(long) ctx->ctx_id, r, ctx->ctx_mta_pflags,
922 				ctx->ctx_mta_aflags);
923 			return _SMFIS_ABORT;
924 		}
925 		else
926 		{
927 			ctx->ctx_aflags = m_aflags;
928 			ctx->ctx_pflags = m_pflags;
929 			ctx->ctx_pflags2mta = m_pflags;
930 		}
931 
932 		/* check whether some flags need to be "faked" */
933 		i = ctx->ctx_pflags2mta;
934 		if ((ctx->ctx_mta_pflags & i) != i)
935 		{
936 			unsigned int idx;
937 			unsigned long b;
938 
939 			/*
940 			**  If some behavior can be faked (set in fake_pflags),
941 			**  but the MTA doesn't support it, then unset
942 			**  that flag in the value that is sent to the MTA.
943 			*/
944 
945 			for (idx = 0; idx < 32; idx++)
946 			{
947 				b = 1 << idx;
948 				if ((ctx->ctx_mta_pflags & b) != b &&
949 				    (fake_pflags & b) == b)
950 					ctx->ctx_pflags2mta &= ~b;
951 			}
952 		}
953 	}
954 	else
955 	{
956 		/*
957 		**  Set the protocol flags based on the values determined
958 		**  in mi_listener() which checked the defined callbacks.
959 		*/
960 
961 		ctx->ctx_pflags2mta = ctx->ctx_pflags;
962 	}
963 
964 	/* check whether actions and protocol requirements can be satisfied */
965 	i = ctx->ctx_aflags;
966 	if ((i & ctx->ctx_mta_aflags) != i)
967 	{
968 		smi_log(SMI_LOG_ERR,
969 			"%s: st_optionneg[%ld]: 0x%lx does not fulfill action requirements 0x%x",
970 			ctx->ctx_smfi->xxfi_name,
971 			(long) ctx->ctx_id, ctx->ctx_mta_aflags, i);
972 		return _SMFIS_ABORT;
973 	}
974 
975 	i = ctx->ctx_pflags2mta;
976 	if ((ctx->ctx_mta_pflags & i) != i)
977 	{
978 		/*
979 		**  Older MTAs do not support some protocol steps.
980 		**  As this protocol is a bit "wierd" (it asks for steps
981 		**  NOT to be taken/sent) we have to check whether we
982 		**  should turn off those "negative" requests.
983 		**  Currently these are only SMFIP_NODATA and SMFIP_NOUNKNOWN.
984 		*/
985 
986 		if (bitset(SMFIP_NODATA, ctx->ctx_pflags2mta) &&
987 		    !bitset(SMFIP_NODATA, ctx->ctx_mta_pflags))
988 			ctx->ctx_pflags2mta &= ~SMFIP_NODATA;
989 		if (bitset(SMFIP_NOUNKNOWN, ctx->ctx_pflags2mta) &&
990 		    !bitset(SMFIP_NOUNKNOWN, ctx->ctx_mta_pflags))
991 			ctx->ctx_pflags2mta &= ~SMFIP_NOUNKNOWN;
992 		i = ctx->ctx_pflags2mta;
993 	}
994 
995 	if ((ctx->ctx_mta_pflags & i) != i)
996 	{
997 		smi_log(SMI_LOG_ERR,
998 			"%s: st_optionneg[%ld]: 0x%lx does not fulfill protocol requirements 0x%x",
999 			ctx->ctx_smfi->xxfi_name,
1000 			(long) ctx->ctx_id, ctx->ctx_mta_pflags, i);
1001 		return _SMFIS_ABORT;
1002 	}
1003 
1004 	if (ctx->ctx_dbg > 3)
1005 		sm_dprintf("[%ld] milter_negotiate:"
1006 			" mta_actions=0x%lx, mta_flags=0x%lx"
1007 			" actions=0x%lx, flags=0x%lx\n"
1008 			, (long) ctx->ctx_id
1009 			, ctx->ctx_mta_aflags, ctx->ctx_mta_pflags
1010 			, ctx->ctx_aflags, ctx->ctx_pflags);
1011 
1012 	return _SMFIS_OPTIONS;
1013 }
1014 
1015 /*
1016 **  ST_CONNECTINFO -- receive connection information
1017 **
1018 **	Parameters:
1019 **		g -- generic argument structure
1020 **
1021 **	Returns:
1022 **		continue or filter-specified value
1023 */
1024 
1025 static int
1026 st_connectinfo(g)
1027 	genarg *g;
1028 {
1029 	size_t l;
1030 	size_t i;
1031 	char *s, family;
1032 	unsigned short port = 0;
1033 	_SOCK_ADDR sockaddr;
1034 	sfsistat (*fi_connect) __P((SMFICTX *, char *, _SOCK_ADDR *));
1035 
1036 	if (g == NULL)
1037 		return _SMFIS_ABORT;
1038 	mi_clr_macros(g->a_ctx, g->a_idx + 1);
1039 	if (g->a_ctx->ctx_smfi == NULL ||
1040 	    (fi_connect = g->a_ctx->ctx_smfi->xxfi_connect) == NULL)
1041 		return SMFIS_CONTINUE;
1042 
1043 	s = g->a_buf;
1044 	i = 0;
1045 	l = g->a_len;
1046 	while (s[i] != '\0' && i <= l)
1047 		++i;
1048 	if (i + 1 >= l)
1049 		return _SMFIS_ABORT;
1050 
1051 	/* Move past trailing \0 in host string */
1052 	i++;
1053 	family = s[i++];
1054 	(void) memset(&sockaddr, '\0', sizeof sockaddr);
1055 	if (family != SMFIA_UNKNOWN)
1056 	{
1057 		if (i + sizeof port >= l)
1058 		{
1059 			smi_log(SMI_LOG_ERR,
1060 				"%s: connect[%ld]: wrong len %d >= %d",
1061 				g->a_ctx->ctx_smfi->xxfi_name,
1062 				(long) g->a_ctx->ctx_id, (int) i, (int) l);
1063 			return _SMFIS_ABORT;
1064 		}
1065 		(void) memcpy((void *) &port, (void *) (s + i),
1066 			      sizeof port);
1067 		i += sizeof port;
1068 
1069 		/* make sure string is terminated */
1070 		if (s[l - 1] != '\0')
1071 			return _SMFIS_ABORT;
1072 # if NETINET
1073 		if (family == SMFIA_INET)
1074 		{
1075 			if (inet_aton(s + i, (struct in_addr *) &sockaddr.sin.sin_addr)
1076 			    != 1)
1077 			{
1078 				smi_log(SMI_LOG_ERR,
1079 					"%s: connect[%ld]: inet_aton failed",
1080 					g->a_ctx->ctx_smfi->xxfi_name,
1081 					(long) g->a_ctx->ctx_id);
1082 				return _SMFIS_ABORT;
1083 			}
1084 			sockaddr.sa.sa_family = AF_INET;
1085 			if (port > 0)
1086 				sockaddr.sin.sin_port = port;
1087 		}
1088 		else
1089 # endif /* NETINET */
1090 # if NETINET6
1091 		if (family == SMFIA_INET6)
1092 		{
1093 			if (mi_inet_pton(AF_INET6, s + i,
1094 					 &sockaddr.sin6.sin6_addr) != 1)
1095 			{
1096 				smi_log(SMI_LOG_ERR,
1097 					"%s: connect[%ld]: mi_inet_pton failed",
1098 					g->a_ctx->ctx_smfi->xxfi_name,
1099 					(long) g->a_ctx->ctx_id);
1100 				return _SMFIS_ABORT;
1101 			}
1102 			sockaddr.sa.sa_family = AF_INET6;
1103 			if (port > 0)
1104 				sockaddr.sin6.sin6_port = port;
1105 		}
1106 		else
1107 # endif /* NETINET6 */
1108 # if NETUNIX
1109 		if (family == SMFIA_UNIX)
1110 		{
1111 			if (sm_strlcpy(sockaddr.sunix.sun_path, s + i,
1112 			    sizeof sockaddr.sunix.sun_path) >=
1113 			    sizeof sockaddr.sunix.sun_path)
1114 			{
1115 				smi_log(SMI_LOG_ERR,
1116 					"%s: connect[%ld]: path too long",
1117 					g->a_ctx->ctx_smfi->xxfi_name,
1118 					(long) g->a_ctx->ctx_id);
1119 				return _SMFIS_ABORT;
1120 			}
1121 			sockaddr.sunix.sun_family = AF_UNIX;
1122 		}
1123 		else
1124 # endif /* NETUNIX */
1125 		{
1126 			smi_log(SMI_LOG_ERR,
1127 				"%s: connect[%ld]: unknown family %d",
1128 				g->a_ctx->ctx_smfi->xxfi_name,
1129 				(long) g->a_ctx->ctx_id, family);
1130 			return _SMFIS_ABORT;
1131 		}
1132 	}
1133 	return (*fi_connect)(g->a_ctx, g->a_buf,
1134 			     family != SMFIA_UNKNOWN ? &sockaddr : NULL);
1135 }
1136 
1137 /*
1138 **  ST_EOH -- end of headers
1139 **
1140 **	Parameters:
1141 **		g -- generic argument structure
1142 **
1143 **	Returns:
1144 **		continue or filter-specified value
1145 */
1146 
1147 static int
1148 st_eoh(g)
1149 	genarg *g;
1150 {
1151 	sfsistat (*fi_eoh) __P((SMFICTX *));
1152 
1153 	if (g == NULL)
1154 		return _SMFIS_ABORT;
1155 	if (g->a_ctx->ctx_smfi != NULL &&
1156 	    (fi_eoh = g->a_ctx->ctx_smfi->xxfi_eoh) != NULL)
1157 		return (*fi_eoh)(g->a_ctx);
1158 	return SMFIS_CONTINUE;
1159 }
1160 
1161 /*
1162 **  ST_DATA -- DATA command
1163 **
1164 **	Parameters:
1165 **		g -- generic argument structure
1166 **
1167 **	Returns:
1168 **		continue or filter-specified value
1169 */
1170 
1171 static int
1172 st_data(g)
1173 	genarg *g;
1174 {
1175 	sfsistat (*fi_data) __P((SMFICTX *));
1176 
1177 	if (g == NULL)
1178 		return _SMFIS_ABORT;
1179 	if (g->a_ctx->ctx_smfi != NULL &&
1180 	    (fi_data = g->a_ctx->ctx_smfi->xxfi_data) != NULL)
1181 		return (*fi_data)(g->a_ctx);
1182 	return SMFIS_CONTINUE;
1183 }
1184 
1185 /*
1186 **  ST_HELO -- helo/ehlo command
1187 **
1188 **	Parameters:
1189 **		g -- generic argument structure
1190 **
1191 **	Returns:
1192 **		continue or filter-specified value
1193 */
1194 
1195 static int
1196 st_helo(g)
1197 	genarg *g;
1198 {
1199 	sfsistat (*fi_helo) __P((SMFICTX *, char *));
1200 
1201 	if (g == NULL)
1202 		return _SMFIS_ABORT;
1203 	mi_clr_macros(g->a_ctx, g->a_idx + 1);
1204 	if (g->a_ctx->ctx_smfi != NULL &&
1205 	    (fi_helo = g->a_ctx->ctx_smfi->xxfi_helo) != NULL)
1206 	{
1207 		/* paranoia: check for terminating '\0' */
1208 		if (g->a_len == 0 || g->a_buf[g->a_len - 1] != '\0')
1209 			return MI_FAILURE;
1210 		return (*fi_helo)(g->a_ctx, g->a_buf);
1211 	}
1212 	return SMFIS_CONTINUE;
1213 }
1214 
1215 /*
1216 **  ST_HEADER -- header line
1217 **
1218 **	Parameters:
1219 **		g -- generic argument structure
1220 **
1221 **	Returns:
1222 **		continue or filter-specified value
1223 */
1224 
1225 static int
1226 st_header(g)
1227 	genarg *g;
1228 {
1229 	char *hf, *hv;
1230 	sfsistat (*fi_header) __P((SMFICTX *, char *, char *));
1231 
1232 	if (g == NULL)
1233 		return _SMFIS_ABORT;
1234 	if (g->a_ctx->ctx_smfi == NULL ||
1235 	    (fi_header = g->a_ctx->ctx_smfi->xxfi_header) == NULL)
1236 		return SMFIS_CONTINUE;
1237 	if (dec_arg2(g->a_buf, g->a_len, &hf, &hv) == MI_SUCCESS)
1238 		return (*fi_header)(g->a_ctx, hf, hv);
1239 	else
1240 		return _SMFIS_ABORT;
1241 }
1242 
1243 #define ARGV_FCT(lf, rf, idx)					\
1244 	char **argv;						\
1245 	sfsistat (*lf) __P((SMFICTX *, char **));		\
1246 	int r;							\
1247 								\
1248 	if (g == NULL)						\
1249 		return _SMFIS_ABORT;				\
1250 	mi_clr_macros(g->a_ctx, g->a_idx + 1);			\
1251 	if (g->a_ctx->ctx_smfi == NULL ||			\
1252 	    (lf = g->a_ctx->ctx_smfi->rf) == NULL)		\
1253 		return SMFIS_CONTINUE;				\
1254 	if ((argv = dec_argv(g->a_buf, g->a_len)) == NULL)	\
1255 		return _SMFIS_ABORT;				\
1256 	r = (*lf)(g->a_ctx, argv);				\
1257 	free(argv);						\
1258 	return r;
1259 
1260 /*
1261 **  ST_SENDER -- MAIL FROM command
1262 **
1263 **	Parameters:
1264 **		g -- generic argument structure
1265 **
1266 **	Returns:
1267 **		continue or filter-specified value
1268 */
1269 
1270 static int
1271 st_sender(g)
1272 	genarg *g;
1273 {
1274 	ARGV_FCT(fi_envfrom, xxfi_envfrom, CI_MAIL)
1275 }
1276 
1277 /*
1278 **  ST_RCPT -- RCPT TO command
1279 **
1280 **	Parameters:
1281 **		g -- generic argument structure
1282 **
1283 **	Returns:
1284 **		continue or filter-specified value
1285 */
1286 
1287 static int
1288 st_rcpt(g)
1289 	genarg *g;
1290 {
1291 	ARGV_FCT(fi_envrcpt, xxfi_envrcpt, CI_RCPT)
1292 }
1293 
1294 /*
1295 **  ST_UNKNOWN -- unrecognized or unimplemented command
1296 **
1297 **	Parameters:
1298 **		g -- generic argument structure
1299 **
1300 **	Returns:
1301 **		continue or filter-specified value
1302 */
1303 
1304 static int
1305 st_unknown(g)
1306 	genarg *g;
1307 {
1308 	sfsistat (*fi_unknown) __P((SMFICTX *, const char *));
1309 
1310 	if (g == NULL)
1311 		return _SMFIS_ABORT;
1312 	if (g->a_ctx->ctx_smfi != NULL &&
1313 	    (fi_unknown = g->a_ctx->ctx_smfi->xxfi_unknown) != NULL)
1314 		return (*fi_unknown)(g->a_ctx, (const char *) g->a_buf);
1315 	return SMFIS_CONTINUE;
1316 }
1317 
1318 /*
1319 **  ST_MACROS -- deal with macros received from the MTA
1320 **
1321 **	Parameters:
1322 **		g -- generic argument structure
1323 **
1324 **	Returns:
1325 **		continue/keep
1326 **
1327 **	Side effects:
1328 **		set pointer in macro array to current values.
1329 */
1330 
1331 static int
1332 st_macros(g)
1333 	genarg *g;
1334 {
1335 	int i;
1336 	char **argv;
1337 
1338 	if (g == NULL || g->a_len < 1)
1339 		return _SMFIS_FAIL;
1340 	if ((argv = dec_argv(g->a_buf + 1, g->a_len - 1)) == NULL)
1341 		return _SMFIS_FAIL;
1342 	switch (g->a_buf[0])
1343 	{
1344 	  case SMFIC_CONNECT:
1345 		i = CI_CONN;
1346 		break;
1347 	  case SMFIC_HELO:
1348 		i = CI_HELO;
1349 		break;
1350 	  case SMFIC_MAIL:
1351 		i = CI_MAIL;
1352 		break;
1353 	  case SMFIC_RCPT:
1354 		i = CI_RCPT;
1355 		break;
1356 	  case SMFIC_DATA:
1357 		i = CI_DATA;
1358 		break;
1359 	  case SMFIC_BODYEOB:
1360 		i = CI_EOM;
1361 		break;
1362 	  case SMFIC_EOH:
1363 		i = CI_EOH;
1364 		break;
1365 	  default:
1366 		free(argv);
1367 		return _SMFIS_FAIL;
1368 	}
1369 	if (g->a_ctx->ctx_mac_ptr[i] != NULL)
1370 		free(g->a_ctx->ctx_mac_ptr[i]);
1371 	if (g->a_ctx->ctx_mac_buf[i] != NULL)
1372 		free(g->a_ctx->ctx_mac_buf[i]);
1373 	g->a_ctx->ctx_mac_ptr[i] = argv;
1374 	g->a_ctx->ctx_mac_buf[i] = g->a_buf;
1375 	return _SMFIS_KEEP;
1376 }
1377 
1378 /*
1379 **  ST_QUIT -- quit command
1380 **
1381 **	Parameters:
1382 **		g -- generic argument structure
1383 **
1384 **	Returns:
1385 **		noreply
1386 */
1387 
1388 /* ARGSUSED */
1389 static int
1390 st_quit(g)
1391 	genarg *g;
1392 {
1393 	sfsistat (*fi_close) __P((SMFICTX *));
1394 
1395 	if (g == NULL)
1396 		return _SMFIS_ABORT;
1397 	if (g->a_ctx->ctx_smfi != NULL &&
1398 	    (fi_close = g->a_ctx->ctx_smfi->xxfi_close) != NULL)
1399 		(void) (*fi_close)(g->a_ctx);
1400 	mi_clr_macros(g->a_ctx, 0);
1401 	return _SMFIS_NOREPLY;
1402 }
1403 
1404 /*
1405 **  ST_BODYCHUNK -- deal with a piece of the mail body
1406 **
1407 **	Parameters:
1408 **		g -- generic argument structure
1409 **
1410 **	Returns:
1411 **		continue or filter-specified value
1412 */
1413 
1414 static int
1415 st_bodychunk(g)
1416 	genarg *g;
1417 {
1418 	sfsistat (*fi_body) __P((SMFICTX *, unsigned char *, size_t));
1419 
1420 	if (g == NULL)
1421 		return _SMFIS_ABORT;
1422 	if (g->a_ctx->ctx_smfi != NULL &&
1423 	    (fi_body = g->a_ctx->ctx_smfi->xxfi_body) != NULL)
1424 		return (*fi_body)(g->a_ctx, (unsigned char *)g->a_buf,
1425 				  g->a_len);
1426 	return SMFIS_CONTINUE;
1427 }
1428 
1429 /*
1430 **  ST_BODYEND -- deal with the last piece of the mail body
1431 **
1432 **	Parameters:
1433 **		g -- generic argument structure
1434 **
1435 **	Returns:
1436 **		continue or filter-specified value
1437 **
1438 **	Side effects:
1439 **		sends a reply for the body part (if non-empty).
1440 */
1441 
1442 static int
1443 st_bodyend(g)
1444 	genarg *g;
1445 {
1446 	sfsistat r;
1447 	sfsistat (*fi_body) __P((SMFICTX *, unsigned char *, size_t));
1448 	sfsistat (*fi_eom) __P((SMFICTX *));
1449 
1450 	if (g == NULL)
1451 		return _SMFIS_ABORT;
1452 	r = SMFIS_CONTINUE;
1453 	if (g->a_ctx->ctx_smfi != NULL)
1454 	{
1455 		if ((fi_body = g->a_ctx->ctx_smfi->xxfi_body) != NULL &&
1456 		    g->a_len > 0)
1457 		{
1458 			socket_t sd;
1459 			struct timeval timeout;
1460 
1461 			timeout.tv_sec = g->a_ctx->ctx_timeout;
1462 			timeout.tv_usec = 0;
1463 			sd = g->a_ctx->ctx_sd;
1464 			r = (*fi_body)(g->a_ctx, (unsigned char *)g->a_buf,
1465 				       g->a_len);
1466 			if (r != SMFIS_CONTINUE &&
1467 			    sendreply(r, sd, &timeout, g->a_ctx) != MI_SUCCESS)
1468 				return _SMFIS_ABORT;
1469 		}
1470 	}
1471 	if (r == SMFIS_CONTINUE &&
1472 	    (fi_eom = g->a_ctx->ctx_smfi->xxfi_eom) != NULL)
1473 		return (*fi_eom)(g->a_ctx);
1474 	return r;
1475 }
1476 
1477 /*
1478 **  ST_ABORTFCT -- deal with aborts
1479 **
1480 **	Parameters:
1481 **		g -- generic argument structure
1482 **
1483 **	Returns:
1484 **		abort or filter-specified value
1485 */
1486 
1487 static int
1488 st_abortfct(g)
1489 	genarg *g;
1490 {
1491 	sfsistat (*fi_abort) __P((SMFICTX *));
1492 
1493 	if (g == NULL)
1494 		return _SMFIS_ABORT;
1495 	if (g != NULL && g->a_ctx->ctx_smfi != NULL &&
1496 	    (fi_abort = g->a_ctx->ctx_smfi->xxfi_abort) != NULL)
1497 		(void) (*fi_abort)(g->a_ctx);
1498 	return _SMFIS_NOREPLY;
1499 }
1500 
1501 /*
1502 **  TRANS_OK -- is the state transition ok?
1503 **
1504 **	Parameters:
1505 **		old -- old state
1506 **		new -- new state
1507 **
1508 **	Returns:
1509 **		state transition ok
1510 */
1511 
1512 static bool
1513 trans_ok(old, new)
1514 	int old, new;
1515 {
1516 	int s, n;
1517 
1518 	s = old;
1519 	if (s >= SIZE_NEXT_STATES)
1520 		return false;
1521 	do
1522 	{
1523 		/* is this state transition allowed? */
1524 		if ((MI_MASK(new) & next_states[s]) != 0)
1525 			return true;
1526 
1527 		/*
1528 		**  no: try next state;
1529 		**  this works since the relevant states are ordered
1530 		**  strict sequentially
1531 		*/
1532 
1533 		n = s + 1;
1534 		if (n >= SIZE_NEXT_STATES)
1535 			return false;
1536 
1537 		/*
1538 		**  can we actually "skip" this state?
1539 		**  see fix_stm() which sets this bit for those
1540 		**  states which the filter program is not interested in
1541 		*/
1542 
1543 		if (bitset(NX_SKIP, next_states[n]))
1544 			s = n;
1545 		else
1546 			return false;
1547 	} while (s < SIZE_NEXT_STATES);
1548 	return false;
1549 }
1550 
1551 /*
1552 **  FIX_STM -- add "skip" bits to the state transition table
1553 **
1554 **	Parameters:
1555 **		ctx -- context structure
1556 **
1557 **	Returns:
1558 **		None.
1559 **
1560 **	Side effects:
1561 **		may change state transition table.
1562 */
1563 
1564 static void
1565 fix_stm(ctx)
1566 	SMFICTX_PTR ctx;
1567 {
1568 	unsigned long fl;
1569 
1570 	if (ctx == NULL || ctx->ctx_smfi == NULL)
1571 		return;
1572 	fl = ctx->ctx_pflags;
1573 	if (bitset(SMFIP_NOCONNECT, fl))
1574 		next_states[ST_CONN] |= NX_SKIP;
1575 	if (bitset(SMFIP_NOHELO, fl))
1576 		next_states[ST_HELO] |= NX_SKIP;
1577 	if (bitset(SMFIP_NOMAIL, fl))
1578 		next_states[ST_MAIL] |= NX_SKIP;
1579 	if (bitset(SMFIP_NORCPT, fl))
1580 		next_states[ST_RCPT] |= NX_SKIP;
1581 	if (bitset(SMFIP_NOHDRS, fl))
1582 		next_states[ST_HDRS] |= NX_SKIP;
1583 	if (bitset(SMFIP_NOEOH, fl))
1584 		next_states[ST_EOHS] |= NX_SKIP;
1585 	if (bitset(SMFIP_NOBODY, fl))
1586 		next_states[ST_BODY] |= NX_SKIP;
1587 	if (bitset(SMFIP_NODATA, fl))
1588 		next_states[ST_DATA] |= NX_SKIP;
1589 	if (bitset(SMFIP_NOUNKNOWN, fl))
1590 		next_states[ST_UNKN] |= NX_SKIP;
1591 }
1592 
1593 /*
1594 **  DEC_ARGV -- split a buffer into a list of strings, NULL terminated
1595 **
1596 **	Parameters:
1597 **		buf -- buffer with several strings
1598 **		len -- length of buffer
1599 **
1600 **	Returns:
1601 **		array of pointers to the individual strings
1602 */
1603 
1604 static char **
1605 dec_argv(buf, len)
1606 	char *buf;
1607 	size_t len;
1608 {
1609 	char **s;
1610 	size_t i;
1611 	int elem, nelem;
1612 
1613 	nelem = 0;
1614 	for (i = 0; i < len; i++)
1615 	{
1616 		if (buf[i] == '\0')
1617 			++nelem;
1618 	}
1619 	if (nelem == 0)
1620 		return NULL;
1621 
1622 	/* last entry is only for the name */
1623 	s = (char **)malloc((nelem + 1) * (sizeof *s));
1624 	if (s == NULL)
1625 		return NULL;
1626 	s[0] = buf;
1627 	for (i = 0, elem = 0; i < len && elem < nelem; i++)
1628 	{
1629 		if (buf[i] == '\0')
1630 		{
1631 			++elem;
1632 			if (i + 1 >= len)
1633 				s[elem] = NULL;
1634 			else
1635 				s[elem] = &(buf[i + 1]);
1636 		}
1637 	}
1638 
1639 	/* overwrite last entry (already done above, just paranoia) */
1640 	s[elem] = NULL;
1641 	return s;
1642 }
1643 
1644 /*
1645 **  DEC_ARG2 -- split a buffer into two strings
1646 **
1647 **	Parameters:
1648 **		buf -- buffer with two strings
1649 **		len -- length of buffer
1650 **		s1,s2 -- pointer to result strings
1651 **
1652 **	Returns:
1653 **		MI_FAILURE/MI_SUCCESS
1654 */
1655 
1656 static int
1657 dec_arg2(buf, len, s1, s2)
1658 	char *buf;
1659 	size_t len;
1660 	char **s1;
1661 	char **s2;
1662 {
1663 	size_t i;
1664 
1665 	/* paranoia: check for terminating '\0' */
1666 	if (len == 0 || buf[len - 1] != '\0')
1667 		return MI_FAILURE;
1668 	*s1 = buf;
1669 	for (i = 1; i < len && buf[i] != '\0'; i++)
1670 		continue;
1671 	if (i >= len - 1)
1672 		return MI_FAILURE;
1673 	*s2 = buf + i + 1;
1674 	return MI_SUCCESS;
1675 }
1676 
1677 /*
1678 **  SENDOK -- is it ok for the filter to send stuff to the MTA?
1679 **
1680 **	Parameters:
1681 **		ctx -- context structure
1682 **		flag -- flag to check
1683 **
1684 **	Returns:
1685 **		sending allowed (in current state)
1686 */
1687 
1688 bool
1689 mi_sendok(ctx, flag)
1690 	SMFICTX_PTR ctx;
1691 	int flag;
1692 {
1693 	if (ctx == NULL || ctx->ctx_smfi == NULL)
1694 		return false;
1695 
1696 	/* did the milter request this operation? */
1697 	if (flag != 0 && !bitset(flag, ctx->ctx_aflags))
1698 		return false;
1699 
1700 	/* are we in the correct state? It must be "End of Message". */
1701 	return ctx->ctx_state == ST_ENDM;
1702 }
1703 
1704 #if _FFR_WORKERS_POOL
1705 /*
1706 **  MI_RD_SOCKET_READY - checks if the socket is ready for read(2)
1707 **
1708 **	Parameters:
1709 **		sd -- socket_t
1710 **
1711 **	Returns:
1712 **		true iff socket is ready for read(2)
1713 */
1714 
1715 #define MI_RD_CMD_TO  1
1716 #define MI_RD_MAX_ERR 16
1717 
1718 static bool
1719 mi_rd_socket_ready (sd)
1720 	socket_t sd;
1721 {
1722 	int n;
1723 	int nerr = 0;
1724 #if SM_CONF_POLL
1725 		struct pollfd pfd;
1726 #else /* SM_CONF_POLL */
1727 		fd_set	rd_set, exc_set;
1728 #endif /* SM_CONF_POLL */
1729 
1730 	do
1731 	{
1732 #if SM_CONF_POLL
1733 		pfd.fd = sd;
1734 		pfd.events = POLLIN;
1735 		pfd.revents = 0;
1736 
1737 		n = poll(&pfd, 1, MI_RD_CMD_TO);
1738 #else /* SM_CONF_POLL */
1739 		struct timeval timeout;
1740 
1741 		FD_ZERO(&rd_set);
1742 		FD_ZERO(&exc_set);
1743 		FD_SET(sd, &rd_set);
1744 		FD_SET(sd, &exc_set);
1745 
1746 		timeout.tv_sec = MI_RD_CMD_TO / 1000;
1747 		timeout.tv_usec = 0;
1748 		n = select(sd + 1, &rd_set, NULL, &exc_set, &timeout);
1749 #endif /* SM_CONF_POLL */
1750 
1751 		if (n < 0)
1752 		{
1753 			if (errno == EINTR)
1754 			{
1755 				nerr++;
1756 				continue;
1757 			}
1758 			return true;
1759 		}
1760 
1761 		if (n == 0)
1762 			return false;
1763 		break;
1764 	} while (nerr < MI_RD_MAX_ERR);
1765 	if (nerr >= MI_RD_MAX_ERR)
1766 		return false;
1767 
1768 #if SM_CONF_POLL
1769 	return (pfd.revents != 0);
1770 #else /* SM_CONF_POLL */
1771 	return FD_ISSET(sd, &rd_set) || FD_ISSET(sd, &exc_set);
1772 #endif /* SM_CONF_POLL */
1773 }
1774 #endif /* _FFR_WORKERS_POOL */
1775