[exim.git] / src / src / lookups / dbmdb.c

/*************************************************
*     Exim - an Internet mail transport agent    *
*************************************************/

/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */

#include "../exim.h"
#include "lf_functions.h"


/*************************************************
*              Open entry point                  *
*************************************************/

/* See local README for interface description */

static void *
dbmdb_open(const uschar * filename, uschar ** errmsg)
{
uschar * dirname = string_copy(filename);
uschar * s;
EXIM_DB *yield = NULL;

if ((s = Ustrrchr(dirname, '/'))) *s = '\0';
EXIM_DBOPEN(filename, dirname, O_RDONLY, 0, &yield);
if (!yield)
  {
  int save_errno = errno;
  *errmsg = string_open_failed(errno, "%s as a %s file", filename, EXIM_DBTYPE);
  errno = save_errno;
  }
return yield;
}


/*************************************************
*             Check entry point                  *
*************************************************/

/* This needs to know more about the underlying files than is good for it!
We need to know what the real file names are in order to check the owners and
modes. If USE_DB is set, we know it is Berkeley DB, which uses an unmodified
file name. If USE_TDB or USE_GDBM is set, we know it is tdb or gdbm, which do
the same. Otherwise, for safety, we have to check for x.db or x.dir and x.pag.
*/

static BOOL
dbmdb_check(void *handle, const uschar *filename, int modemask, uid_t *owners,
  gid_t *owngroups, uschar **errmsg)
{
int rc;
handle = handle;    /* Keep picky compilers happy */

#if defined(USE_DB) || defined(USE_TDB) || defined(USE_GDBM)
rc = lf_check_file(-1, filename, S_IFREG, modemask, owners, owngroups,
  "dbm", errmsg);
#else
  {
  uschar filebuffer[256];
  (void)sprintf(CS filebuffer, "%.250s.db", filename);
  rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
    "dbm", errmsg);
  if (rc < 0)        /* stat() failed */
    {
    (void)sprintf(CS filebuffer, "%.250s.dir", filename);
    rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
      "dbm", errmsg);
    if (rc == 0)     /* x.dir was OK */
      {
      (void)sprintf(CS filebuffer, "%.250s.pag", filename);
      rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
        "dbm", errmsg);
      }
    }
  }
#endif

return rc == 0;
}


/*************************************************
*              Find entry point                  *
*************************************************/

/* See local README for interface description. This function adds 1 to
the keylength in order to include the terminating zero. */

static int
dbmdb_find(void * handle, const uschar * filename, const uschar * keystring,
  int length, uschar ** result, uschar ** errmsg, uint * do_cache,
  const uschar * opts)
{
EXIM_DB *d = (EXIM_DB *)handle;
EXIM_DATUM key, data;

filename = filename;    /* Keep picky compilers happy */
errmsg = errmsg;
do_cache = do_cache;

EXIM_DATUM_INIT(key);               /* Some DBM libraries require datums to */
EXIM_DATUM_INIT(data);              /* be cleared before use. */
EXIM_DATUM_DATA(key) = CS keystring;
EXIM_DATUM_SIZE(key) = length + 1;

if (EXIM_DBGET(d, key, data))
  {
  *result = string_copyn(US EXIM_DATUM_DATA(data), EXIM_DATUM_SIZE(data));
  EXIM_DATUM_FREE(data);            /* Some DBM libraries need a free() call */
  return OK;
  }
return FAIL;
}


/*************************************************
*      Find entry point - no zero on key         *
*************************************************/

/* See local README for interface description */

static int
dbmnz_find(void * handle, const uschar * filename, const uschar * keystring,
  int length, uschar ** result, uschar ** errmsg, uint * do_cache,
  const uschar * opts)
{
return dbmdb_find(handle, filename, keystring, length-1, result, errmsg,
  do_cache, opts);
}


/*************************************************
*     Find entry point - zero-joined list key    *
*************************************************/

/*
 * The parameter passed as a key is a list in normal Exim list syntax.
 * The elements of that list are joined together on NUL, with no trailing
 * NUL, to form the key.
 */

static int
dbmjz_find(void * handle, const uschar * filename, const uschar * keystring,
  int length, uschar ** result, uschar ** errmsg, uint * do_cache,
  const uschar * opts)
{
uschar *key_item, *key_buffer, *key_p;
const uschar *key_elems = keystring;
int buflen, bufleft, key_item_len, sep = 0;

/* To a first approximation, the size of the lookup key needs to be about,
or less than, the length of the delimited list passed in + 1. */

buflen = length + 3;
key_buffer = store_get(buflen, is_tainted(keystring));

key_buffer[0] = '\0';

key_p = key_buffer;
bufleft = buflen;

/* In all cases of an empty list item, we can set 1 and advance by 1 and then
pick up the trailing NUL from the previous list item, EXCEPT when at the
beginning of the output string, in which case we need to supply that NUL
ourselves.  */
while ((key_item = string_nextinlist(&key_elems, &sep, key_p, bufleft)) != NULL)
  {
  key_item_len = Ustrlen(key_item) + 1;
  if (key_item_len == 1)
    {
    key_p[0] = '\0';
    if (key_p == key_buffer)
      {
      key_p[1] = '\0';
      key_item_len += 1;
      }
    }

  bufleft -= key_item_len;
  if (bufleft <= 0)
    {
    /* The string_nextinlist() will stop at buffer size, but we should always
    have at least 1 character extra, so some assumption has failed. */
    *errmsg = string_copy(US"Ran out of buffer space for joining elements");
    return DEFER;
    }
  key_p += key_item_len;
  }

if (key_p == key_buffer)
  {
  *errmsg = string_copy(US"empty list key");
  return FAIL;
  }

/* We do not pass in the final NULL; if needed, the list should include an
empty element to put one in. Boundary: key length 1, is a NULL */
key_item_len = key_p - key_buffer - 1;

DEBUG(D_lookup) debug_printf_indent("NUL-joined key length: %d\n", key_item_len);

/* beware that dbmdb_find() adds 1 to length to get back terminating NUL, so
because we've calculated the real length, we need to subtract one more here */

return dbmdb_find(handle, filename, key_buffer, key_item_len - 1,
    result, errmsg, do_cache, opts);
}


/*************************************************
*              Close entry point                 *
*************************************************/

/* See local README for interface description */

void
static dbmdb_close(void *handle)
{
EXIM_DBCLOSE((EXIM_DB *)handle);
}


/*************************************************
*         Version reporting entry point          *
*************************************************/

/* See local README for interface description. */

#include "../version.h"

void
dbm_version_report(FILE *f)
{
#ifdef DYNLOOKUP
fprintf(f, "Library version: DBM: Exim version %s\n", EXIM_VERSION_STR);
#endif
}


lookup_info dbm_lookup_info = {
  .name = US"dbm",			/* lookup name */
  .type = lookup_absfile,		/* uses absolute file name */
  .open = dbmdb_open,			/* open function */
  .check = dbmdb_check,			/* check function */
  .find = dbmdb_find,			/* find function */
  .close = dbmdb_close,			/* close function */
  .tidy = NULL,				/* no tidy function */
  .quote = NULL,			/* no quoting function */
  .version_report = dbm_version_report             /* version reporting */
};

lookup_info dbmz_lookup_info = {
  .name = US"dbmnz",			/* lookup name */
  .type = lookup_absfile,		/* uses absolute file name */
  .open = dbmdb_open,			/* sic */     /* open function */
  .check = dbmdb_check,			/* sic */     /* check function */
  .find = dbmnz_find,			/* find function */
  .close = dbmdb_close,			/* sic */     /* close function */
  .tidy = NULL,				/* no tidy function */
  .quote = NULL,			/* no quoting function */
  .version_report = NULL                           /* no version reporting (redundant) */
};

lookup_info dbmjz_lookup_info = {
  .name = US"dbmjz",			/* lookup name */
  .type = lookup_absfile,		/* uses absolute file name */
  .open = dbmdb_open,			/* sic */     /* open function */
  .check = dbmdb_check,			/* sic */     /* check function */
  .find = dbmjz_find,			/* find function */
  .close = dbmdb_close,			/* sic */     /* close function */
  .tidy = NULL,				/* no tidy function */
  .quote = NULL,			/* no quoting function */
  .version_report = NULL                           /* no version reporting (redundant) */
};

#ifdef DYNLOOKUP
#define dbmdb_lookup_module_info _lookup_module_info
#endif

static lookup_info *_lookup_list[] = { &dbm_lookup_info, &dbmz_lookup_info, &dbmjz_lookup_info };
lookup_module_info dbmdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 3 };

/* End of lookups/dbmdb.c */
Commit	Line	Data
	1	/*************************************************
	2	* Exim - an Internet mail transport agent *
	3	*************************************************/
	4
	5	/* Copyright (c) University of Cambridge 1995 - 2018 */
	6	/* See the file NOTICE for conditions of use and distribution. */
	7
	8	#include "../exim.h"
	9	#include "lf_functions.h"
	10
	11
	12	/*************************************************
	13	* Open entry point *
	14	*************************************************/
	15
	16	/* See local README for interface description */
	17
	18	static void *
	19	dbmdb_open(const uschar * filename, uschar ** errmsg)
	20	{
	21	uschar * dirname = string_copy(filename);
	22	uschar * s;
	23	EXIM_DB *yield = NULL;
	24
	25	if ((s = Ustrrchr(dirname, '/'))) *s = '\0';
	26	EXIM_DBOPEN(filename, dirname, O_RDONLY, 0, &yield);
	27	if (!yield)
	28	{
	29	int save_errno = errno;
	30	*errmsg = string_open_failed(errno, "%s as a %s file", filename, EXIM_DBTYPE);
	31	errno = save_errno;
	32	}
	33	return yield;
	34	}
	35
	36
	37
	38	/*************************************************
	39	* Check entry point *
	40	*************************************************/
	41
	42	/* This needs to know more about the underlying files than is good for it!
	43	We need to know what the real file names are in order to check the owners and
	44	modes. If USE_DB is set, we know it is Berkeley DB, which uses an unmodified
	45	file name. If USE_TDB or USE_GDBM is set, we know it is tdb or gdbm, which do
	46	the same. Otherwise, for safety, we have to check for x.db or x.dir and x.pag.
	47	*/
	48
	49	static BOOL
	50	dbmdb_check(void handle, const uschar filename, int modemask, uid_t *owners,
	51	gid_t owngroups, uschar *errmsg)
	52	{
	53	int rc;
	54	handle = handle; /* Keep picky compilers happy */
	55
	56	#if defined(USE_DB) \|\| defined(USE_TDB) \|\| defined(USE_GDBM)
	57	rc = lf_check_file(-1, filename, S_IFREG, modemask, owners, owngroups,
	58	"dbm", errmsg);
	59	#else
	60	{
	61	uschar filebuffer[256];
	62	(void)sprintf(CS filebuffer, "%.250s.db", filename);
	63	rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
	64	"dbm", errmsg);
	65	if (rc < 0) /* stat() failed */
	66	{
	67	(void)sprintf(CS filebuffer, "%.250s.dir", filename);
	68	rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
	69	"dbm", errmsg);
	70	if (rc == 0) /* x.dir was OK */
	71	{
	72	(void)sprintf(CS filebuffer, "%.250s.pag", filename);
	73	rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
	74	"dbm", errmsg);
	75	}
	76	}
	77	}
	78	#endif
	79
	80	return rc == 0;
	81	}
	82
	83
	84
	85	/*************************************************
	86	* Find entry point *
	87	*************************************************/
	88
	89	/* See local README for interface description. This function adds 1 to
	90	the keylength in order to include the terminating zero. */
	91
	92	static int
	93	dbmdb_find(void * handle, const uschar * filename, const uschar * keystring,
	94	int length, uschar result, uschar errmsg, uint * do_cache,
	95	const uschar * opts)
	96	{
	97	EXIM_DB d = (EXIM_DB )handle;
	98	EXIM_DATUM key, data;
	99
	100	filename = filename; /* Keep picky compilers happy */
	101	errmsg = errmsg;
	102	do_cache = do_cache;
	103
	104	EXIM_DATUM_INIT(key); /* Some DBM libraries require datums to */
	105	EXIM_DATUM_INIT(data); /* be cleared before use. */
	106	EXIM_DATUM_DATA(key) = CS keystring;
	107	EXIM_DATUM_SIZE(key) = length + 1;
	108
	109	if (EXIM_DBGET(d, key, data))
	110	{
	111	*result = string_copyn(US EXIM_DATUM_DATA(data), EXIM_DATUM_SIZE(data));
	112	EXIM_DATUM_FREE(data); /* Some DBM libraries need a free() call */
	113	return OK;
	114	}
	115	return FAIL;
	116	}
	117
	118
	119
	120	/*************************************************
	121	* Find entry point - no zero on key *
	122	*************************************************/
	123
	124	/* See local README for interface description */
	125
	126	static int
	127	dbmnz_find(void * handle, const uschar * filename, const uschar * keystring,
	128	int length, uschar result, uschar errmsg, uint * do_cache,
	129	const uschar * opts)
	130	{
	131	return dbmdb_find(handle, filename, keystring, length-1, result, errmsg,
	132	do_cache, opts);
	133	}
	134
	135
	136
	137	/*************************************************
	138	* Find entry point - zero-joined list key *
	139	*************************************************/
	140
	141	/*
	142	* The parameter passed as a key is a list in normal Exim list syntax.
	143	* The elements of that list are joined together on NUL, with no trailing
	144	* NUL, to form the key.
	145	*/
	146
	147	static int
	148	dbmjz_find(void * handle, const uschar * filename, const uschar * keystring,
	149	int length, uschar result, uschar errmsg, uint * do_cache,
	150	const uschar * opts)
	151	{
	152	uschar key_item, key_buffer, *key_p;
	153	const uschar *key_elems = keystring;
	154	int buflen, bufleft, key_item_len, sep = 0;
	155
	156	/* To a first approximation, the size of the lookup key needs to be about,
	157	or less than, the length of the delimited list passed in + 1. */
	158
	159	buflen = length + 3;
	160	key_buffer = store_get(buflen, is_tainted(keystring));
	161
	162	key_buffer[0] = '\0';
	163
	164	key_p = key_buffer;
	165	bufleft = buflen;
	166
	167	/* In all cases of an empty list item, we can set 1 and advance by 1 and then
	168	pick up the trailing NUL from the previous list item, EXCEPT when at the
	169	beginning of the output string, in which case we need to supply that NUL
	170	ourselves. */
	171	while ((key_item = string_nextinlist(&key_elems, &sep, key_p, bufleft)) != NULL)
	172	{
	173	key_item_len = Ustrlen(key_item) + 1;
	174	if (key_item_len == 1)
	175	{
	176	key_p[0] = '\0';
	177	if (key_p == key_buffer)
	178	{
	179	key_p[1] = '\0';
	180	key_item_len += 1;
	181	}
	182	}
	183
	184	bufleft -= key_item_len;
	185	if (bufleft <= 0)
	186	{
	187	/* The string_nextinlist() will stop at buffer size, but we should always
	188	have at least 1 character extra, so some assumption has failed. */
	189	*errmsg = string_copy(US"Ran out of buffer space for joining elements");
	190	return DEFER;
	191	}
	192	key_p += key_item_len;
	193	}
	194
	195	if (key_p == key_buffer)
	196	{
	197	*errmsg = string_copy(US"empty list key");
	198	return FAIL;
	199	}
	200
	201	/* We do not pass in the final NULL; if needed, the list should include an
	202	empty element to put one in. Boundary: key length 1, is a NULL */
	203	key_item_len = key_p - key_buffer - 1;
	204
	205	DEBUG(D_lookup) debug_printf_indent("NUL-joined key length: %d\n", key_item_len);
	206
	207	/* beware that dbmdb_find() adds 1 to length to get back terminating NUL, so
	208	because we've calculated the real length, we need to subtract one more here */
	209
	210	return dbmdb_find(handle, filename, key_buffer, key_item_len - 1,
	211	result, errmsg, do_cache, opts);
	212	}
	213
	214
	215
	216	/*************************************************
	217	* Close entry point *
	218	*************************************************/
	219
	220	/* See local README for interface description */
	221
	222	void
	223	static dbmdb_close(void *handle)
	224	{
	225	EXIM_DBCLOSE((EXIM_DB *)handle);
	226	}
	227
	228
	229
	230	/*************************************************
	231	* Version reporting entry point *
	232	*************************************************/
	233
	234	/* See local README for interface description. */
	235
	236	#include "../version.h"
	237
	238	void
	239	dbm_version_report(FILE *f)
	240	{
	241	#ifdef DYNLOOKUP
	242	fprintf(f, "Library version: DBM: Exim version %s\n", EXIM_VERSION_STR);
	243	#endif
	244	}
	245
	246
	247	lookup_info dbm_lookup_info = {
	248	.name = US"dbm", /* lookup name */
	249	.type = lookup_absfile, /* uses absolute file name */
	250	.open = dbmdb_open, /* open function */
	251	.check = dbmdb_check, /* check function */
	252	.find = dbmdb_find, /* find function */
	253	.close = dbmdb_close, /* close function */
	254	.tidy = NULL, /* no tidy function */
	255	.quote = NULL, /* no quoting function */
	256	.version_report = dbm_version_report /* version reporting */
	257	};
	258
	259	lookup_info dbmz_lookup_info = {
	260	.name = US"dbmnz", /* lookup name */
	261	.type = lookup_absfile, /* uses absolute file name */
	262	.open = dbmdb_open, /* sic / / open function */
	263	.check = dbmdb_check, /* sic / / check function */
	264	.find = dbmnz_find, /* find function */
	265	.close = dbmdb_close, /* sic / / close function */
	266	.tidy = NULL, /* no tidy function */
	267	.quote = NULL, /* no quoting function */
	268	.version_report = NULL /* no version reporting (redundant) */
	269	};
	270
	271	lookup_info dbmjz_lookup_info = {
	272	.name = US"dbmjz", /* lookup name */
	273	.type = lookup_absfile, /* uses absolute file name */
	274	.open = dbmdb_open, /* sic / / open function */
	275	.check = dbmdb_check, /* sic / / check function */
	276	.find = dbmjz_find, /* find function */
	277	.close = dbmdb_close, /* sic / / close function */
	278	.tidy = NULL, /* no tidy function */
	279	.quote = NULL, /* no quoting function */
	280	.version_report = NULL /* no version reporting (redundant) */
	281	};
	282
	283	#ifdef DYNLOOKUP
	284	#define dbmdb_lookup_module_info _lookup_module_info
	285	#endif
	286
	287	static lookup_info *_lookup_list[] = { &dbm_lookup_info, &dbmz_lookup_info, &dbmjz_lookup_info };
	288	lookup_module_info dbmdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 3 };
	289
	290	/* End of lookups/dbmdb.c */