xref: /netbsd-src/external/ibm-public/postfix/dist/src/global/dict_sqlite.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: dict_sqlite.c,v 1.1.1.3 2013/01/02 18:58:57 tron Exp $	*/
2 
3 /*++
4 /* NAME
5 /*	dict_sqlite 3
6 /* SUMMARY
7 /*	dictionary manager interface to SQLite3 databases
8 /* SYNOPSIS
9 /*	#include <dict_sqlite.h>
10 /*
11 /*	DICT	*dict_sqlite_open(name, open_flags, dict_flags)
12 /*	const char *name;
13 /*	int	open_flags;
14 /*	int	dict_flags;
15 /* DESCRIPTION
16 /*	dict_sqlite_open() creates a dictionary of type 'sqlite'.
17 /*	This dictionary is an interface for the postfix key->value
18 /*	mappings to SQLite.  The result is a pointer to the installed
19 /*	dictionary.
20 /* .PP
21 /*	Arguments:
22 /* .IP name
23 /*	Either the path to the SQLite configuration file (if it
24 /*	starts with '/' or '.'), or the prefix which will be used
25 /*	to obtain main.cf configuration parameters for this search.
26 /*
27 /*	In the first case, the configuration parameters below are
28 /*	specified in the file as \fIname\fR=\fIvalue\fR pairs.
29 /*
30 /*	In the second case, the configuration parameters are prefixed
31 /*	with the value of \fIname\fR and an underscore, and they
32 /*	are specified in main.cf.  For example, if this value is
33 /*	\fIsqlitecon\fR, the parameters would look like
34 /*	\fIsqlitecon_dbpath\fR, \fIsqlitecon_query\fR, and so on.
35 /* .IP open_flags
36 /*	Must be O_RDONLY.
37 /* .IP dict_flags
38 /*	See dict_open(3).
39 /* .PP
40 /*	Configuration parameters:
41 /* .IP dbpath
42 /*	Path to SQLite database
43 /* .IP query
44 /*	Query template. Before the query is actually issued, variable
45 /*	substitutions are performed. See sqlite_table(5) for details.
46 /* .IP result_format
47 /*	The format used to expand results from queries.  Substitutions
48 /*	are performed as described in sqlite_table(5). Defaults to
49 /*	returning the lookup result unchanged.
50 /* .IP expansion_limit
51 /*	Limit (if any) on the total number of lookup result values.
52 /*	Lookups which exceed the limit fail with dict->error=DICT_ERR_RETRY.
53 /*	Note that each non-empty (and non-NULL) column of a
54 /*	multi-column result row counts as one result.
55 /* .IP "select_field, where_field, additional_conditions"
56 /*	Legacy query interface.
57 /* SEE ALSO
58 /*	dict(3) generic dictionary manager
59 /* AUTHOR(S)
60 /*	Axel Steiner
61 /*	ast@treibsand.com
62 /*
63 /*	Adopted and updated by:
64 /*	Wietse Venema
65 /*	IBM T.J. Watson Research
66 /*	P.O. Box 704
67 /*	Yorktown Heights, NY 10598, USA
68 /*--*/
69 
70 /* System library. */
71 
72 #include <sys_defs.h>
73 #include <string.h>
74 
75 #ifdef HAS_SQLITE
76 #include <sqlite3.h>
77 
78 #if !defined(SQLITE_VERSION_NUMBER) || (SQLITE_VERSION_NUMBER < 3005004)
79 #define sqlite3_prepare_v2 sqlite3_prepare
80 #endif
81 
82 /* Utility library. */
83 
84 #include <msg.h>
85 #include <dict.h>
86 #include <vstring.h>
87 #include <stringops.h>
88 #include <mymalloc.h>
89 
90 /* Global library. */
91 
92 #include <cfg_parser.h>
93 #include <db_common.h>
94 
95 /* Application-specific. */
96 
97 #include <dict_sqlite.h>
98 
99 typedef struct {
100     DICT    dict;			/* generic member */
101     CFG_PARSER *parser;			/* common parameter parser */
102     sqlite3 *db;			/* sqlite handle */
103     char   *query;			/* db_common_expand() query */
104     char   *result_format;		/* db_common_expand() result_format */
105     void   *ctx;			/* db_common_parse() context */
106     char   *dbpath;			/* dbpath config attribute */
107     int     expansion_limit;		/* expansion_limit config attribute */
108 } DICT_SQLITE;
109 
110 /* dict_sqlite_quote - escape SQL metacharacters in input string */
111 
112 static void dict_sqlite_quote(DICT *dict, const char *raw_text, VSTRING *result)
113 {
114     char   *quoted_text;
115 
116     quoted_text = sqlite3_mprintf("%q", raw_text);
117     /* Fix 20100616 */
118     if (quoted_text == 0)
119 	msg_fatal("dict_sqlite_quote: out of memory");
120     vstring_strcat(result, quoted_text);
121     sqlite3_free(quoted_text);
122 }
123 
124 /* dict_sqlite_close - close the database */
125 
126 static void dict_sqlite_close(DICT *dict)
127 {
128     const char *myname = "dict_sqlite_close";
129     DICT_SQLITE *dict_sqlite = (DICT_SQLITE *) dict;
130 
131     if (msg_verbose)
132 	msg_info("%s: %s", myname, dict_sqlite->parser->name);
133 
134     if (sqlite3_close(dict_sqlite->db) != SQLITE_OK)
135 	msg_fatal("%s: close %s failed", myname, dict_sqlite->parser->name);
136     cfg_parser_free(dict_sqlite->parser);
137     myfree(dict_sqlite->dbpath);
138     myfree(dict_sqlite->query);
139     myfree(dict_sqlite->result_format);
140     if (dict_sqlite->ctx)
141 	db_common_free_ctx(dict_sqlite->ctx);
142     if (dict->fold_buf)
143 	vstring_free(dict->fold_buf);
144     dict_free(dict);
145 }
146 
147 /* dict_sqlite_lookup - find database entry */
148 
149 static const char *dict_sqlite_lookup(DICT *dict, const char *name)
150 {
151     const char *myname = "dict_sqlite_lookup";
152     DICT_SQLITE *dict_sqlite = (DICT_SQLITE *) dict;
153     sqlite3_stmt *sql_stmt;
154     const char *query_remainder;
155     static VSTRING *query;
156     static VSTRING *result;
157     const char *retval;
158     int     expansion = 0;
159     int     status;
160     int     domain_rc;
161 
162     /*
163      * In case of return without lookup (skipped key, etc.).
164      */
165     dict->error = 0;
166 
167     /*
168      * Don't frustrate future attempts to make Postfix UTF-8 transparent.
169      */
170     if (!valid_utf_8(name, strlen(name))) {
171 	if (msg_verbose)
172 	    msg_info("%s: %s: Skipping lookup of non-UTF-8 key '%s'",
173 		     myname, dict_sqlite->parser->name, name);
174 	return (0);
175     }
176 
177     /*
178      * Optionally fold the key. Folding may be enabled on on-the-fly.
179      */
180     if (dict->flags & DICT_FLAG_FOLD_FIX) {
181 	if (dict->fold_buf == 0)
182 	    dict->fold_buf = vstring_alloc(100);
183 	vstring_strcpy(dict->fold_buf, name);
184 	name = lowercase(vstring_str(dict->fold_buf));
185     }
186 
187     /*
188      * Apply the optional domain filter for email address lookups.
189      */
190     if ((domain_rc = db_common_check_domain(dict_sqlite->ctx, name)) == 0) {
191 	if (msg_verbose)
192 	    msg_info("%s: %s: Skipping lookup of '%s'",
193 		     myname, dict_sqlite->parser->name, name);
194 	return (0);
195     }
196     if (domain_rc < 0)
197 	DICT_ERR_VAL_RETURN(dict, domain_rc, (char *) 0);
198 
199     /*
200      * Expand the query and query the database.
201      */
202 #define INIT_VSTR(buf, len) do { \
203 	if (buf == 0) \
204 		buf = vstring_alloc(len); \
205 	VSTRING_RESET(buf); \
206 	VSTRING_TERMINATE(buf); \
207     } while (0)
208 
209     INIT_VSTR(query, 10);
210 
211     if (!db_common_expand(dict_sqlite->ctx, dict_sqlite->query,
212 			  name, 0, query, dict_sqlite_quote))
213 	return (0);
214 
215     if (msg_verbose)
216 	msg_info("%s: %s: Searching with query %s",
217 		 myname, dict_sqlite->parser->name, vstring_str(query));
218 
219     if (sqlite3_prepare_v2(dict_sqlite->db, vstring_str(query), -1,
220 			   &sql_stmt, &query_remainder) != SQLITE_OK)
221 	msg_fatal("%s: %s: SQL prepare failed: %s\n",
222 		  myname, dict_sqlite->parser->name,
223 		  sqlite3_errmsg(dict_sqlite->db));
224 
225     if (*query_remainder && msg_verbose)
226 	msg_info("%s: %s: Ignoring text at end of query: %s",
227 		 myname, dict_sqlite->parser->name, query_remainder);
228 
229     /*
230      * Retrieve and expand the result(s).
231      */
232     INIT_VSTR(result, 10);
233     while ((status = sqlite3_step(sql_stmt)) != SQLITE_DONE) {
234 	if (status == SQLITE_ROW) {
235 	    if (db_common_expand(dict_sqlite->ctx, dict_sqlite->result_format,
236 				 (char *) sqlite3_column_text(sql_stmt, 0),
237 				 name, result, 0)
238 		&& dict_sqlite->expansion_limit > 0
239 		&& ++expansion > dict_sqlite->expansion_limit) {
240 		msg_warn("%s: %s: Expansion limit exceeded for key '%s'",
241 			 myname, dict_sqlite->parser->name, name);
242 		dict->error = DICT_ERR_RETRY;
243 		break;
244 	    }
245 	}
246 	/* Fix 20100616 */
247 	else {
248 	    msg_warn("%s: %s: SQL step failed for query '%s': %s\n",
249 		     myname, dict_sqlite->parser->name,
250 		     vstring_str(query), sqlite3_errmsg(dict_sqlite->db));
251 	    dict->error = DICT_ERR_RETRY;
252 	    break;
253 	}
254     }
255 
256     /*
257      * Clean up.
258      */
259     if (sqlite3_finalize(sql_stmt))
260 	msg_fatal("%s: %s: SQL finalize failed for query '%s': %s\n",
261 		  myname, dict_sqlite->parser->name,
262 		  vstring_str(query), sqlite3_errmsg(dict_sqlite->db));
263 
264     return ((dict->error == 0 && *(retval = vstring_str(result)) != 0) ?
265 	    retval : 0);
266 }
267 
268 /* sqlite_parse_config - parse sqlite configuration file */
269 
270 static void sqlite_parse_config(DICT_SQLITE *dict_sqlite, const char *sqlitecf)
271 {
272     VSTRING *buf;
273 
274     /*
275      * Parse the primary configuration parameters, and emulate the legacy
276      * query interface if necessary. This simplifies migration from one SQL
277      * database type to another.
278      */
279     dict_sqlite->dbpath = cfg_get_str(dict_sqlite->parser, "dbpath", "", 1, 0);
280     dict_sqlite->query = cfg_get_str(dict_sqlite->parser, "query", NULL, 0, 0);
281     if (dict_sqlite->query == 0) {
282 	buf = vstring_alloc(100);
283 	db_common_sql_build_query(buf, dict_sqlite->parser);
284 	dict_sqlite->query = vstring_export(buf);
285     }
286     dict_sqlite->result_format =
287 	cfg_get_str(dict_sqlite->parser, "result_format", "%s", 1, 0);
288     dict_sqlite->expansion_limit =
289 	cfg_get_int(dict_sqlite->parser, "expansion_limit", 0, 0, 0);
290 
291     /*
292      * Parse the query / result templates and the optional domain filter.
293      */
294     dict_sqlite->ctx = 0;
295     (void) db_common_parse(&dict_sqlite->dict, &dict_sqlite->ctx,
296 			   dict_sqlite->query, 1);
297     (void) db_common_parse(0, &dict_sqlite->ctx, dict_sqlite->result_format, 0);
298     db_common_parse_domain(dict_sqlite->parser, dict_sqlite->ctx);
299 
300     /*
301      * Maps that use substring keys should only be used with the full input
302      * key.
303      */
304     if (db_common_dict_partial(dict_sqlite->ctx))
305 	dict_sqlite->dict.flags |= DICT_FLAG_PATTERN;
306     else
307 	dict_sqlite->dict.flags |= DICT_FLAG_FIXED;
308 }
309 
310 /* dict_sqlite_open - open sqlite database */
311 
312 DICT   *dict_sqlite_open(const char *name, int open_flags, int dict_flags)
313 {
314     DICT_SQLITE *dict_sqlite;
315     CFG_PARSER *parser;
316 
317     /*
318      * Sanity checks.
319      */
320     if (open_flags != O_RDONLY)
321 	return (dict_surrogate(DICT_TYPE_SQLITE, name, open_flags, dict_flags,
322 			       "%s:%s map requires O_RDONLY access mode",
323 			       DICT_TYPE_SQLITE, name));
324 
325     /*
326      * Open the configuration file.
327      */
328     if ((parser = cfg_parser_alloc(name)) == 0)
329 	return (dict_surrogate(DICT_TYPE_SQLITE, name, open_flags, dict_flags,
330 			       "open %s: %m", name));
331 
332     dict_sqlite = (DICT_SQLITE *) dict_alloc(DICT_TYPE_SQLITE, name,
333 					     sizeof(DICT_SQLITE));
334     dict_sqlite->dict.lookup = dict_sqlite_lookup;
335     dict_sqlite->dict.close = dict_sqlite_close;
336     dict_sqlite->dict.flags = dict_flags;
337 
338     dict_sqlite->parser = parser;
339     sqlite_parse_config(dict_sqlite, name);
340 
341     if (sqlite3_open(dict_sqlite->dbpath, &dict_sqlite->db))
342 	msg_fatal("%s:%s: Can't open database: %s\n",
343 		  DICT_TYPE_SQLITE, name, sqlite3_errmsg(dict_sqlite->db));
344 
345     dict_sqlite->dict.owner = cfg_get_owner(dict_sqlite->parser);
346 
347     return (DICT_DEBUG (&dict_sqlite->dict));
348 }
349 
350 #endif
351