engine.c revision 90792
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
11#include <sm/gen.h>
12SM_RCSID("@(#)$Id: engine.c,v 8.102 2001/12/13 17:10:00 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 */
21struct 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
29typedef struct arg_struct genarg;
30
31/* structure for commands received from MTA */
32struct 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
42typedef 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	/* start 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#if CI_RCPT >= MAX_MACROS_ENTRIES
68ERROR: do not compile with CI_RCPT >= MAX_MACROS_ENTRIES
69#endif
70
71/* function prototypes */
72static int	st_abortfct __P((genarg *));
73static int	st_macros __P((genarg *));
74static int	st_optionneg __P((genarg *));
75static int	st_bodychunk __P((genarg *));
76static int	st_connectinfo __P((genarg *));
77static int	st_bodyend __P((genarg *));
78static int	st_helo __P((genarg *));
79static int	st_header __P((genarg *));
80static int	st_sender __P((genarg *));
81static int	st_rcpt __P((genarg *));
82static int	st_eoh __P((genarg *));
83static int	st_quit __P((genarg *));
84static int	sendreply __P((sfsistat, socket_t, struct timeval *, SMFICTX_PTR));
85static void	fix_stm __P((SMFICTX_PTR));
86static bool	trans_ok __P((int, int));
87static char	**dec_argv __P((char *, size_t));
88static int	dec_arg2 __P((char *, size_t, char **, char **));
89
90/* states */
91#define ST_NONE	(-1)
92#define ST_INIT	0	/* initial state */
93#define ST_OPTS	1	/* option negotiation */
94#define ST_CONN	2	/* connection info */
95#define ST_HELO	3	/* helo */
96#define ST_MAIL	4	/* mail from */
97#define ST_RCPT	5	/* rcpt to */
98#define ST_HDRS	6	/* headers */
99#define ST_EOHS	7	/* end of headers */
100#define ST_BODY	8	/* body */
101#define ST_ENDM	9	/* end of message */
102#define ST_QUIT	10	/* quit */
103#define ST_ABRT	11	/* abort */
104#define ST_LAST	ST_ABRT
105#define ST_SKIP	15	/* not a state but required for the state table */
106
107/* in a mail transaction? must be before eom according to spec. */
108#define ST_IN_MAIL(st)	((st) >= ST_MAIL && (st) < ST_ENDM)
109
110/*
111**  set of next states
112**  each state (ST_*) corresponds to bit in an int value (1 << state)
113**  each state has a set of allowed transitions ('or' of bits of states)
114**  so a state transition is valid if the mask of the next state
115**  is set in the NX_* value
116**  this function is coded in trans_ok(), see below.
117*/
118
119#define MASK(x)	(0x0001 << (x))	/* generate a bit "mask" for a state */
120#define NX_INIT	(MASK(ST_OPTS))
121#define NX_OPTS	(MASK(ST_CONN))
122#define NX_CONN	(MASK(ST_HELO) | MASK(ST_MAIL))
123#define NX_HELO	(MASK(ST_HELO) | MASK(ST_MAIL))
124#define NX_MAIL	(MASK(ST_RCPT) | MASK(ST_ABRT))
125#define NX_RCPT	(MASK(ST_HDRS) | MASK(ST_EOHS) | \
126		 MASK(ST_BODY) | MASK(ST_ENDM) | \
127		 MASK(ST_RCPT) | MASK(ST_ABRT))
128#define NX_HDRS	(MASK(ST_EOHS) | MASK(ST_HDRS) | MASK(ST_ABRT))
129#define NX_EOHS	(MASK(ST_BODY) | MASK(ST_ENDM) | MASK(ST_ABRT))
130#define NX_BODY	(MASK(ST_ENDM) | MASK(ST_BODY) | MASK(ST_ABRT))
131#define NX_ENDM	(MASK(ST_QUIT) | MASK(ST_MAIL))
132#define NX_QUIT	0
133#define NX_ABRT	0
134#define NX_SKIP MASK(ST_SKIP)
135
136static int next_states[] =
137{
138	NX_INIT,
139	NX_OPTS,
140	NX_CONN,
141	NX_HELO,
142	NX_MAIL,
143	NX_RCPT,
144	NX_HDRS,
145	NX_EOHS,
146	NX_BODY,
147	NX_ENDM,
148	NX_QUIT,
149	NX_ABRT
150};
151
152/* commands received by milter */
153static cmdfct cmds[] =
154{
155{SMFIC_ABORT,	CM_ARG0, ST_ABRT,  CT_CONT,	CI_NONE, st_abortfct	},
156{SMFIC_MACRO,	CM_ARGV, ST_NONE,  CT_KEEP,	CI_NONE, st_macros	},
157{SMFIC_BODY,	CM_ARG1, ST_BODY,  CT_CONT,	CI_NONE, st_bodychunk	},
158{SMFIC_CONNECT,	CM_ARG2, ST_CONN,  CT_CONT,	CI_CONN, st_connectinfo	},
159{SMFIC_BODYEOB,	CM_ARG1, ST_ENDM,  CT_CONT,	CI_NONE, st_bodyend	},
160{SMFIC_HELO,	CM_ARG1, ST_HELO,  CT_CONT,	CI_HELO, st_helo	},
161{SMFIC_HEADER,	CM_ARG2, ST_HDRS,  CT_CONT,	CI_NONE, st_header	},
162{SMFIC_MAIL,	CM_ARGV, ST_MAIL,  CT_CONT,	CI_MAIL, st_sender	},
163{SMFIC_OPTNEG,	CM_ARGO, ST_OPTS,  CT_CONT,	CI_NONE, st_optionneg	},
164{SMFIC_EOH,	CM_ARG0, ST_EOHS,  CT_CONT,	CI_NONE, st_eoh		},
165{SMFIC_QUIT,	CM_ARG0, ST_QUIT,  CT_END,	CI_NONE, st_quit	},
166{SMFIC_RCPT,	CM_ARGV, ST_RCPT,  CT_IGNO,	CI_RCPT, st_rcpt	}
167};
168
169/* additional (internal) reply codes */
170#define _SMFIS_KEEP	20
171#define _SMFIS_ABORT	21
172#define _SMFIS_OPTIONS	22
173#define _SMFIS_NOREPLY	23
174#define _SMFIS_FAIL	(-1)
175#define _SMFIS_NONE	(-2)
176
177/*
178**  MI_ENGINE -- receive commands and process them
179**
180**	Parameters:
181**		ctx -- context structure
182**
183**	Returns:
184**		MI_FAILURE/MI_SUCCESS
185*/
186int
187mi_engine(ctx)
188	SMFICTX_PTR ctx;
189{
190	size_t len;
191	int i;
192	socket_t sd;
193	int ret = MI_SUCCESS;
194	int ncmds = sizeof(cmds) / sizeof(cmdfct);
195	int curstate = ST_INIT;
196	int newstate;
197	bool call_abort;
198	sfsistat r;
199	char cmd;
200	char *buf = NULL;
201	genarg arg;
202	struct timeval timeout;
203	int (*f) __P((genarg *));
204	sfsistat (*fi_abort) __P((SMFICTX *));
205	sfsistat (*fi_close) __P((SMFICTX *));
206
207	arg.a_ctx = ctx;
208	sd = ctx->ctx_sd;
209	fi_abort = ctx->ctx_smfi->xxfi_abort;
210	mi_clr_macros(ctx, 0);
211	fix_stm(ctx);
212	r = _SMFIS_NONE;
213	do
214	{
215		/* call abort only if in a mail transaction */
216		call_abort = ST_IN_MAIL(curstate);
217		timeout.tv_sec = ctx->ctx_timeout;
218		timeout.tv_usec = 0;
219		if (mi_stop() == MILTER_ABRT)
220		{
221			if (ctx->ctx_dbg > 3)
222				sm_dprintf("[%d] milter_abort\n",
223					(int) ctx->ctx_id);
224			ret = MI_FAILURE;
225			break;
226		}
227
228		/*
229		**  Notice: buf is allocated by mi_rd_cmd() and it will
230		**  usually be free()d after it has been used in f().
231		**  However, if the function returns _SMFIS_KEEP then buf
232		**  contains macros and will not be free()d.
233		**  Hence r must be set to _SMFIS_NONE if a new buf is
234		**  allocated to avoid problem with housekeeping, esp.
235		**  if the code "break"s out of the loop.
236		*/
237
238		r = _SMFIS_NONE;
239		if ((buf = mi_rd_cmd(sd, &timeout, &cmd, &len,
240				     ctx->ctx_smfi->xxfi_name)) == NULL &&
241		    cmd < SMFIC_VALIDCMD)
242		{
243			if (ctx->ctx_dbg > 5)
244				sm_dprintf("[%d] mi_engine: mi_rd_cmd error (%x)\n",
245					(int) ctx->ctx_id, (int) cmd);
246
247			/*
248			**  eof is currently treated as failure ->
249			**  abort() instead of close(), otherwise use:
250			**  if (cmd != SMFIC_EOF)
251			*/
252
253			ret = MI_FAILURE;
254			break;
255		}
256		if (ctx->ctx_dbg > 4)
257			sm_dprintf("[%d] got cmd '%c' len %d\n",
258				(int) ctx->ctx_id, cmd, len);
259		for (i = 0; i < ncmds; i++)
260		{
261			if (cmd == cmds[i].cm_cmd)
262				break;
263		}
264		if (i >= ncmds)
265		{
266			/* unknown command */
267			if (ctx->ctx_dbg > 1)
268				sm_dprintf("[%d] cmd '%c' unknown\n",
269					(int) ctx->ctx_id, cmd);
270			ret = MI_FAILURE;
271			break;
272		}
273		if ((f = cmds[i].cm_fct) == NULL)
274		{
275			/* stop for now */
276			if (ctx->ctx_dbg > 1)
277				sm_dprintf("[%d] cmd '%c' not impl\n",
278					(int) ctx->ctx_id, cmd);
279			ret = MI_FAILURE;
280			break;
281		}
282
283		/* is new state ok? */
284		newstate = cmds[i].cm_next;
285		if (ctx->ctx_dbg > 5)
286			sm_dprintf("[%d] cur %x new %x nextmask %x\n",
287				(int) ctx->ctx_id,
288				curstate, newstate, next_states[curstate]);
289
290		if (newstate != ST_NONE && !trans_ok(curstate, newstate))
291		{
292			if (ctx->ctx_dbg > 1)
293				sm_dprintf("[%d] abort: cur %d (%x) new %d (%x) next %x\n",
294					(int) ctx->ctx_id,
295					curstate, MASK(curstate),
296					newstate, MASK(newstate),
297					next_states[curstate]);
298
299			/* call abort only if in a mail transaction */
300			if (fi_abort != NULL && call_abort)
301				(void) (*fi_abort)(ctx);
302
303			/*
304			**  try to reach the new state from HELO
305			**  if it can't be reached, ignore the command.
306			*/
307
308			curstate = ST_HELO;
309			if (!trans_ok(curstate, newstate))
310			{
311				free(buf);
312				buf = NULL;
313				continue;
314			}
315		}
316		arg.a_len = len;
317		arg.a_buf = buf;
318		if (newstate != ST_NONE)
319		{
320			curstate = newstate;
321			ctx->ctx_state = curstate;
322		}
323		arg.a_idx = cmds[i].cm_macros;
324
325		/* call function to deal with command */
326		r = (*f)(&arg);
327		if (r != _SMFIS_KEEP && buf != NULL)
328		{
329			free(buf);
330			buf = NULL;
331		}
332		if (sendreply(r, sd, &timeout, ctx) != MI_SUCCESS)
333		{
334			ret = MI_FAILURE;
335			break;
336		}
337
338		call_abort = ST_IN_MAIL(curstate);
339		if (r == SMFIS_ACCEPT)
340		{
341			/* accept mail, no further actions taken */
342			curstate = ST_HELO;
343		}
344		else if (r == SMFIS_REJECT || r == SMFIS_DISCARD ||
345			 r ==  SMFIS_TEMPFAIL)
346		{
347			/*
348			**  further actions depend on current state
349			**  if the IGNO bit is set: "ignore" the error,
350			**  i.e., stay in the current state
351			*/
352			if (!bitset(CT_IGNO, cmds[i].cm_todo))
353				curstate = ST_HELO;
354		}
355		else if (r == _SMFIS_ABORT)
356		{
357			if (ctx->ctx_dbg > 5)
358				sm_dprintf("[%d] function returned abort\n",
359					(int) ctx->ctx_id);
360			ret = MI_FAILURE;
361			break;
362		}
363	} while (!bitset(CT_END, cmds[i].cm_todo));
364
365	if (ret != MI_SUCCESS)
366	{
367		/* call abort only if in a mail transaction */
368		if (fi_abort != NULL && call_abort)
369			(void) (*fi_abort)(ctx);
370	}
371
372	/* close must always be called */
373	if ((fi_close = ctx->ctx_smfi->xxfi_close) != NULL)
374		(void) (*fi_close)(ctx);
375	if (r != _SMFIS_KEEP && buf != NULL)
376		free(buf);
377	mi_clr_macros(ctx, 0);
378	return ret;
379}
380/*
381**  SENDREPLY -- send a reply to the MTA
382**
383**	Parameters:
384**		r -- reply code
385**		sd -- socket descriptor
386**		timeout_ptr -- (ptr to) timeout to use for sending
387**		ctx -- context structure
388**
389**	Returns:
390**		MI_SUCCESS/MI_FAILURE
391*/
392
393static int
394sendreply(r, sd, timeout_ptr, ctx)
395	sfsistat r;
396	socket_t sd;
397	struct timeval *timeout_ptr;
398	SMFICTX_PTR ctx;
399{
400	int ret = MI_SUCCESS;
401
402	switch (r)
403	{
404	  case SMFIS_CONTINUE:
405		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_CONTINUE, NULL, 0);
406		break;
407	  case SMFIS_TEMPFAIL:
408	  case SMFIS_REJECT:
409		if (ctx->ctx_reply != NULL)
410		{
411			ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_REPLYCODE,
412					ctx->ctx_reply,
413					strlen(ctx->ctx_reply) + 1);
414			free(ctx->ctx_reply);
415			ctx->ctx_reply = NULL;
416		}
417		else
418		{
419			ret = mi_wr_cmd(sd, timeout_ptr, r == SMFIS_REJECT ?
420					SMFIR_REJECT : SMFIR_TEMPFAIL, NULL, 0);
421		}
422		break;
423	  case SMFIS_DISCARD:
424		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_DISCARD, NULL, 0);
425		break;
426	  case SMFIS_ACCEPT:
427		ret = mi_wr_cmd(sd, timeout_ptr, SMFIR_ACCEPT, NULL, 0);
428		break;
429	  case _SMFIS_OPTIONS:
430		{
431			char buf[MILTER_OPTLEN];
432			mi_int32 v;
433
434			v = htonl(ctx->ctx_smfi->xxfi_version);
435			(void) memcpy(&(buf[0]), (void *) &v, MILTER_LEN_BYTES);
436			v = htonl(ctx->ctx_smfi->xxfi_flags);
437			(void) memcpy(&(buf[MILTER_LEN_BYTES]), (void *) &v,
438				      MILTER_LEN_BYTES);
439			v = htonl(ctx->ctx_pflags);
440			(void) memcpy(&(buf[MILTER_LEN_BYTES * 2]), (void *) &v,
441				      MILTER_LEN_BYTES);
442			ret = mi_wr_cmd(sd, timeout_ptr, SMFIC_OPTNEG, buf,
443				       MILTER_OPTLEN);
444		}
445		break;
446	  default:	/* don't send a reply */
447		break;
448	}
449	return ret;
450}
451
452/*
453**  CLR_MACROS -- clear set of macros starting from a given index
454**
455**	Parameters:
456**		ctx -- context structure
457**		m -- index from which to clear all macros
458**
459**	Returns:
460**		None.
461*/
462void
463mi_clr_macros(ctx, m)
464	SMFICTX_PTR ctx;
465	int m;
466{
467	int i;
468
469	for (i = m; i < MAX_MACROS_ENTRIES; i++)
470	{
471		if (ctx->ctx_mac_ptr[i] != NULL)
472		{
473			free(ctx->ctx_mac_ptr[i]);
474			ctx->ctx_mac_ptr[i] = NULL;
475		}
476		if (ctx->ctx_mac_buf[i] != NULL)
477		{
478			free(ctx->ctx_mac_buf[i]);
479			ctx->ctx_mac_buf[i] = NULL;
480		}
481	}
482}
483/*
484**  ST_OPTIONNEG -- negotiate options
485**
486**	Parameters:
487**		g -- generic argument structure
488**
489**	Returns:
490**		abort/send options/continue
491*/
492
493static int
494st_optionneg(g)
495	genarg *g;
496{
497	mi_int32 i, v;
498
499	if (g == NULL || g->a_ctx->ctx_smfi == NULL)
500		return SMFIS_CONTINUE;
501	mi_clr_macros(g->a_ctx, g->a_idx + 1);
502
503	/* check for minimum length */
504	if (g->a_len < MILTER_OPTLEN)
505	{
506		smi_log(SMI_LOG_ERR,
507			"%s: st_optionneg[%d]: len too short %d < %d",
508			g->a_ctx->ctx_smfi->xxfi_name,
509			(int) g->a_ctx->ctx_id, g->a_len,
510			MILTER_OPTLEN);
511		return _SMFIS_ABORT;
512	}
513
514	(void) memcpy((void *) &i, (void *) &(g->a_buf[0]),
515		      MILTER_LEN_BYTES);
516	v = ntohl(i);
517	if (v < g->a_ctx->ctx_smfi->xxfi_version)
518	{
519		/* hard failure for now! */
520		smi_log(SMI_LOG_ERR,
521			"%s: st_optionneg[%d]: version mismatch MTA: %d < milter: %d",
522			g->a_ctx->ctx_smfi->xxfi_name,
523			(int) g->a_ctx->ctx_id, (int) v,
524			g->a_ctx->ctx_smfi->xxfi_version);
525		return _SMFIS_ABORT;
526	}
527
528	(void) memcpy((void *) &i, (void *) &(g->a_buf[MILTER_LEN_BYTES]),
529		      MILTER_LEN_BYTES);
530	v = ntohl(i);
531
532	/* no flags? set to default value for V1 actions */
533	if (v == 0)
534		v = SMFI_V1_ACTS;
535	i = g->a_ctx->ctx_smfi->xxfi_flags;
536	if ((v & i) != i)
537	{
538		smi_log(SMI_LOG_ERR,
539			"%s: st_optionneg[%d]: 0x%x does not fulfill action requirements 0x%x",
540			g->a_ctx->ctx_smfi->xxfi_name,
541			(int) g->a_ctx->ctx_id, v, i);
542		return _SMFIS_ABORT;
543	}
544
545	(void) memcpy((void *) &i, (void *) &(g->a_buf[MILTER_LEN_BYTES * 2]),
546		      MILTER_LEN_BYTES);
547	v = ntohl(i);
548
549	/* no flags? set to default value for V1 protocol */
550	if (v == 0)
551		v = SMFI_V1_PROT;
552	i = g->a_ctx->ctx_pflags;
553	if ((v & i) != i)
554	{
555		smi_log(SMI_LOG_ERR,
556			"%s: st_optionneg[%d]: 0x%x does not fulfill protocol requirements 0x%x",
557			g->a_ctx->ctx_smfi->xxfi_name,
558			(int) g->a_ctx->ctx_id, v, i);
559		return _SMFIS_ABORT;
560	}
561
562	return _SMFIS_OPTIONS;
563}
564/*
565**  ST_CONNECTINFO -- receive connection information
566**
567**	Parameters:
568**		g -- generic argument structure
569**
570**	Returns:
571**		continue or filter-specified value
572*/
573
574static int
575st_connectinfo(g)
576	genarg *g;
577{
578	size_t l;
579	size_t i;
580	char *s, family;
581	unsigned short port = 0;
582	_SOCK_ADDR sockaddr;
583	sfsistat (*fi_connect) __P((SMFICTX *, char *, _SOCK_ADDR *));
584
585	if (g == NULL)
586		return _SMFIS_ABORT;
587	mi_clr_macros(g->a_ctx, g->a_idx + 1);
588	if (g->a_ctx->ctx_smfi == NULL ||
589	    (fi_connect = g->a_ctx->ctx_smfi->xxfi_connect) == NULL)
590		return SMFIS_CONTINUE;
591
592	s = g->a_buf;
593	i = 0;
594	l = g->a_len;
595	while (s[i] != '\0' && i <= l)
596		++i;
597	if (i >= l)
598		return _SMFIS_ABORT;
599
600	/* Move past trailing \0 in host string */
601	i++;
602	family = s[i++];
603	memset(&sockaddr, '\0', sizeof sockaddr);
604	if (family != SMFIA_UNKNOWN)
605	{
606		(void) memcpy((void *) &port, (void *) (s + i),
607			      sizeof port);
608		port = ntohs(port);
609		if ((i += sizeof port) >= l)
610		{
611			smi_log(SMI_LOG_ERR,
612				"%s: connect[%d]: wrong len %d >= %d",
613				g->a_ctx->ctx_smfi->xxfi_name,
614				(int) g->a_ctx->ctx_id, i, l);
615			return _SMFIS_ABORT;
616		}
617# if NETINET
618		if (family == SMFIA_INET)
619		{
620			if (inet_aton(s + i, (struct in_addr *) &sockaddr.sin.sin_addr)
621			    == INADDR_NONE)
622			{
623				smi_log(SMI_LOG_ERR,
624					"%s: connect[%d]: inet_aton failed",
625					g->a_ctx->ctx_smfi->xxfi_name,
626					(int) g->a_ctx->ctx_id);
627				return _SMFIS_ABORT;
628			}
629			sockaddr.sa.sa_family = AF_INET;
630			if (port > 0)
631				sockaddr.sin.sin_port = port;
632		}
633		else
634# endif /* NETINET */
635# if NETINET6
636		if (family == SMFIA_INET6)
637		{
638			if (mi_inet_pton(AF_INET6, s + i,
639					 &sockaddr.sin6.sin6_addr) != 1)
640			{
641				smi_log(SMI_LOG_ERR,
642					"%s: connect[%d]: mi_inet_pton failed",
643					g->a_ctx->ctx_smfi->xxfi_name,
644					(int) g->a_ctx->ctx_id);
645				return _SMFIS_ABORT;
646			}
647			sockaddr.sa.sa_family = AF_INET6;
648			if (port > 0)
649				sockaddr.sin6.sin6_port = port;
650		}
651		else
652# endif /* NETINET6 */
653# if NETUNIX
654		if (family == SMFIA_UNIX)
655		{
656			if (sm_strlcpy(sockaddr.sunix.sun_path, s + i,
657			    sizeof sockaddr.sunix.sun_path) >=
658			    sizeof sockaddr.sunix.sun_path)
659			{
660				smi_log(SMI_LOG_ERR,
661					"%s: connect[%d]: path too long",
662					g->a_ctx->ctx_smfi->xxfi_name,
663					(int) g->a_ctx->ctx_id);
664				return _SMFIS_ABORT;
665			}
666			sockaddr.sunix.sun_family = AF_UNIX;
667		}
668		else
669# endif /* NETUNIX */
670		{
671			smi_log(SMI_LOG_ERR,
672				"%s: connect[%d]: unknown family %d",
673				g->a_ctx->ctx_smfi->xxfi_name,
674				(int) g->a_ctx->ctx_id, family);
675			return _SMFIS_ABORT;
676		}
677	}
678	return (*fi_connect)(g->a_ctx, g->a_buf,
679			     family != SMFIA_UNKNOWN ? &sockaddr : NULL);
680}
681/*
682**  ST_EOH -- end of headers
683**
684**	Parameters:
685**		g -- generic argument structure
686**
687**	Returns:
688**		continue or filter-specified value
689*/
690
691static int
692st_eoh(g)
693	genarg *g;
694{
695	sfsistat (*fi_eoh) __P((SMFICTX *));
696
697	if (g == NULL)
698		return _SMFIS_ABORT;
699	if (g->a_ctx->ctx_smfi != NULL &&
700	    (fi_eoh = g->a_ctx->ctx_smfi->xxfi_eoh) != NULL)
701		return (*fi_eoh)(g->a_ctx);
702	return SMFIS_CONTINUE;
703}
704/*
705**  ST_HELO -- helo/ehlo command
706**
707**	Parameters:
708**		g -- generic argument structure
709**
710**	Returns:
711**		continue or filter-specified value
712*/
713static int
714st_helo(g)
715	genarg *g;
716{
717	sfsistat (*fi_helo) __P((SMFICTX *, char *));
718
719	if (g == NULL)
720		return _SMFIS_ABORT;
721	mi_clr_macros(g->a_ctx, g->a_idx + 1);
722	if (g->a_ctx->ctx_smfi != NULL &&
723	    (fi_helo = g->a_ctx->ctx_smfi->xxfi_helo) != NULL)
724		return (*fi_helo)(g->a_ctx, g->a_buf);
725	return SMFIS_CONTINUE;
726}
727/*
728**  ST_HEADER -- header line
729**
730**	Parameters:
731**		g -- generic argument structure
732**
733**	Returns:
734**		continue or filter-specified value
735*/
736
737static int
738st_header(g)
739	genarg *g;
740{
741	char *hf, *hv;
742	sfsistat (*fi_header) __P((SMFICTX *, char *, char *));
743
744	if (g == NULL)
745		return _SMFIS_ABORT;
746	if (g->a_ctx->ctx_smfi == NULL ||
747	    (fi_header = g->a_ctx->ctx_smfi->xxfi_header) == NULL)
748		return SMFIS_CONTINUE;
749	if (dec_arg2(g->a_buf, g->a_len, &hf, &hv) == MI_SUCCESS)
750		return (*fi_header)(g->a_ctx, hf, hv);
751	else
752		return _SMFIS_ABORT;
753}
754
755#define ARGV_FCT(lf, rf, idx)					\
756	char **argv;						\
757	sfsistat (*lf) __P((SMFICTX *, char **));		\
758	int r;							\
759								\
760	if (g == NULL)						\
761		return _SMFIS_ABORT;				\
762	mi_clr_macros(g->a_ctx, g->a_idx + 1);			\
763	if (g->a_ctx->ctx_smfi == NULL ||			\
764	    (lf = g->a_ctx->ctx_smfi->rf) == NULL)		\
765		return SMFIS_CONTINUE;				\
766	if ((argv = dec_argv(g->a_buf, g->a_len)) == NULL)	\
767		return _SMFIS_ABORT;				\
768	r = (*lf)(g->a_ctx, argv);				\
769	free(argv);						\
770	return r;
771
772/*
773**  ST_SENDER -- MAIL FROM command
774**
775**	Parameters:
776**		g -- generic argument structure
777**
778**	Returns:
779**		continue or filter-specified value
780*/
781
782static int
783st_sender(g)
784	genarg *g;
785{
786	ARGV_FCT(fi_envfrom, xxfi_envfrom, CI_MAIL)
787}
788/*
789**  ST_RCPT -- RCPT TO command
790**
791**	Parameters:
792**		g -- generic argument structure
793**
794**	Returns:
795**		continue or filter-specified value
796*/
797
798static int
799st_rcpt(g)
800	genarg *g;
801{
802	ARGV_FCT(fi_envrcpt, xxfi_envrcpt, CI_RCPT)
803}
804/*
805**  ST_MACROS -- deal with macros received from the MTA
806**
807**	Parameters:
808**		g -- generic argument structure
809**
810**	Returns:
811**		continue/keep
812**
813**	Side effects:
814**		set pointer in macro array to current values.
815*/
816
817static int
818st_macros(g)
819	genarg *g;
820{
821	int i;
822	char **argv;
823
824	if (g == NULL || g->a_len < 1)
825		return _SMFIS_FAIL;
826	if ((argv = dec_argv(g->a_buf + 1, g->a_len - 1)) == NULL)
827		return _SMFIS_FAIL;
828	switch (g->a_buf[0])
829	{
830	  case SMFIC_CONNECT:
831		i = CI_CONN;
832		break;
833	  case SMFIC_HELO:
834		i = CI_HELO;
835		break;
836	  case SMFIC_MAIL:
837		i = CI_MAIL;
838		break;
839	  case SMFIC_RCPT:
840		i = CI_RCPT;
841		break;
842	  default:
843		free(argv);
844		return _SMFIS_FAIL;
845	}
846	if (g->a_ctx->ctx_mac_ptr[i] != NULL)
847		free(g->a_ctx->ctx_mac_ptr[i]);
848	if (g->a_ctx->ctx_mac_buf[i] != NULL)
849		free(g->a_ctx->ctx_mac_buf[i]);
850	g->a_ctx->ctx_mac_ptr[i] = argv;
851	g->a_ctx->ctx_mac_buf[i] = g->a_buf;
852	return _SMFIS_KEEP;
853}
854/*
855**  ST_QUIT -- quit command
856**
857**	Parameters:
858**		g -- generic argument structure
859**
860**	Returns:
861**		noreply
862*/
863
864static int
865st_quit(g)
866	genarg *g;
867{
868	return _SMFIS_NOREPLY;
869}
870/*
871**  ST_BODYCHUNK -- deal with a piece of the mail body
872**
873**	Parameters:
874**		g -- generic argument structure
875**
876**	Returns:
877**		continue or filter-specified value
878*/
879
880static int
881st_bodychunk(g)
882	genarg *g;
883{
884	sfsistat (*fi_body) __P((SMFICTX *, unsigned char *, size_t));
885
886	if (g == NULL)
887		return _SMFIS_ABORT;
888	if (g->a_ctx->ctx_smfi != NULL &&
889	    (fi_body = g->a_ctx->ctx_smfi->xxfi_body) != NULL)
890		return (*fi_body)(g->a_ctx, (unsigned char *)g->a_buf,
891				  g->a_len);
892	return SMFIS_CONTINUE;
893}
894/*
895**  ST_BODYEND -- deal with the last piece of the mail body
896**
897**	Parameters:
898**		g -- generic argument structure
899**
900**	Returns:
901**		continue or filter-specified value
902**
903**	Side effects:
904**		sends a reply for the body part (if non-empty).
905*/
906
907static int
908st_bodyend(g)
909	genarg *g;
910{
911	sfsistat r;
912	sfsistat (*fi_body) __P((SMFICTX *, unsigned char *, size_t));
913	sfsistat (*fi_eom) __P((SMFICTX *));
914
915	if (g == NULL)
916		return _SMFIS_ABORT;
917	r = SMFIS_CONTINUE;
918	if (g->a_ctx->ctx_smfi != NULL)
919	{
920		if ((fi_body = g->a_ctx->ctx_smfi->xxfi_body) != NULL &&
921		    g->a_len > 0)
922		{
923			socket_t sd;
924			struct timeval timeout;
925
926			timeout.tv_sec = g->a_ctx->ctx_timeout;
927			timeout.tv_usec = 0;
928			sd = g->a_ctx->ctx_sd;
929			r = (*fi_body)(g->a_ctx, (unsigned char *)g->a_buf,
930				       g->a_len);
931			if (r != SMFIS_CONTINUE &&
932			    sendreply(r, sd, &timeout, g->a_ctx) != MI_SUCCESS)
933				return _SMFIS_ABORT;
934		}
935	}
936	if (r == SMFIS_CONTINUE &&
937	    (fi_eom = g->a_ctx->ctx_smfi->xxfi_eom) != NULL)
938		return (*fi_eom)(g->a_ctx);
939	return r;
940}
941/*
942**  ST_ABORTFCT -- deal with aborts
943**
944**	Parameters:
945**		g -- generic argument structure
946**
947**	Returns:
948**		abort or filter-specified value
949*/
950
951static int
952st_abortfct(g)
953	genarg *g;
954{
955	sfsistat (*fi_abort) __P((SMFICTX *));
956
957	if (g == NULL)
958		return _SMFIS_ABORT;
959	if (g != NULL && g->a_ctx->ctx_smfi != NULL &&
960	    (fi_abort = g->a_ctx->ctx_smfi->xxfi_abort) != NULL)
961		(void) (*fi_abort)(g->a_ctx);
962	return _SMFIS_NOREPLY;
963}
964/*
965**  TRANS_OK -- is the state transition ok?
966**
967**	Parameters:
968**		old -- old state
969**		new -- new state
970**
971**	Returns:
972**		state transition ok
973*/
974
975static bool
976trans_ok(old, new)
977	int old, new;
978{
979	int s, n;
980
981	s = old;
982	do
983	{
984		/* is this state transition allowed? */
985		if ((MASK(new) & next_states[s]) != 0)
986			return true;
987
988		/*
989		**  no: try next state;
990		**  this works since the relevant states are ordered
991		**  strict sequentially
992		*/
993
994		n = s + 1;
995
996		/*
997		**  can we actually "skip" this state?
998		**  see fix_stm() which sets this bit for those
999		**  states which the filter program is not interested in
1000		*/
1001
1002		if (bitset(NX_SKIP, next_states[n]))
1003			s = n;
1004		else
1005			return false;
1006	} while (s <= ST_LAST);
1007	return false;
1008}
1009/*
1010**  FIX_STM -- add "skip" bits to the state transition table
1011**
1012**	Parameters:
1013**		ctx -- context structure
1014**
1015**	Returns:
1016**		None.
1017**
1018**	Side effects:
1019**		may change state transition table.
1020*/
1021
1022static void
1023fix_stm(ctx)
1024	SMFICTX_PTR ctx;
1025{
1026	unsigned long fl;
1027
1028	if (ctx == NULL || ctx->ctx_smfi == NULL)
1029		return;
1030	fl = ctx->ctx_pflags;
1031	if (bitset(SMFIP_NOCONNECT, fl))
1032		next_states[ST_CONN] |= NX_SKIP;
1033	if (bitset(SMFIP_NOHELO, fl))
1034		next_states[ST_HELO] |= NX_SKIP;
1035	if (bitset(SMFIP_NOMAIL, fl))
1036		next_states[ST_MAIL] |= NX_SKIP;
1037	if (bitset(SMFIP_NORCPT, fl))
1038		next_states[ST_RCPT] |= NX_SKIP;
1039	if (bitset(SMFIP_NOHDRS, fl))
1040		next_states[ST_HDRS] |= NX_SKIP;
1041	if (bitset(SMFIP_NOEOH, fl))
1042		next_states[ST_EOHS] |= NX_SKIP;
1043	if (bitset(SMFIP_NOBODY, fl))
1044		next_states[ST_BODY] |= NX_SKIP;
1045}
1046/*
1047**  DEC_ARGV -- split a buffer into a list of strings, NULL terminated
1048**
1049**	Parameters:
1050**		buf -- buffer with several strings
1051**		len -- length of buffer
1052**
1053**	Returns:
1054**		array of pointers to the individual strings
1055*/
1056
1057static char **
1058dec_argv(buf, len)
1059	char *buf;
1060	size_t len;
1061{
1062	char **s;
1063	size_t i;
1064	int elem, nelem;
1065
1066	nelem = 0;
1067	for (i = 0; i < len; i++)
1068	{
1069		if (buf[i] == '\0')
1070			++nelem;
1071	}
1072	if (nelem == 0)
1073		return NULL;
1074
1075	/* last entry is only for the name */
1076	s = (char **)malloc((nelem + 1) * (sizeof *s));
1077	if (s == NULL)
1078		return NULL;
1079	s[0] = buf;
1080	for (i = 0, elem = 0; i < len && elem < nelem; i++)
1081	{
1082		if (buf[i] == '\0')
1083			s[++elem] = &(buf[i + 1]);
1084	}
1085
1086	/* overwrite last entry */
1087	s[elem] = NULL;
1088	return s;
1089}
1090/*
1091**  DEC_ARG2 -- split a buffer into two strings
1092**
1093**	Parameters:
1094**		buf -- buffer with two strings
1095**		len -- length of buffer
1096**		s1,s2 -- pointer to result strings
1097**
1098**	Returns:
1099**		MI_FAILURE/MI_SUCCESS
1100*/
1101
1102static int
1103dec_arg2(buf, len, s1, s2)
1104	char *buf;
1105	size_t len;
1106	char **s1;
1107	char **s2;
1108{
1109	size_t i;
1110
1111	*s1 = buf;
1112	for (i = 1; i < len && buf[i] != '\0'; i++)
1113		continue;
1114	if (i >= len - 1)
1115		return MI_FAILURE;
1116	*s2 = buf + i + 1;
1117	return MI_SUCCESS;
1118}
1119/*
1120**  SENDOK -- is it ok for the filter to send stuff to the MTA?
1121**
1122**	Parameters:
1123**		ctx -- context structure
1124**		flag -- flag to check
1125**
1126**	Returns:
1127**		sending allowed (in current state)
1128*/
1129
1130bool
1131mi_sendok(ctx, flag)
1132	SMFICTX_PTR ctx;
1133	int flag;
1134{
1135	if (ctx == NULL || ctx->ctx_smfi == NULL)
1136		return false;
1137
1138	/* did the milter request this operation? */
1139	if (flag != 0 && !bitset(flag, ctx->ctx_smfi->xxfi_flags))
1140		return false;
1141
1142	/* are we in the correct state? It must be "End of Message". */
1143	return ctx->ctx_state == ST_ENDM;
1144}
1145