1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2015 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Thanks to Paul Kelly for contributing the original code for these
13 #include "lf_functions.h"
15 #include <mysql.h> /* The system header */
16 #include <mysql_version.h>
19 /* Structure and anchor for caching connections. */
21 typedef struct mysql_connection {
22 struct mysql_connection *next;
27 static mysql_connection *mysql_connections = NULL;
31 /*************************************************
33 *************************************************/
35 /* See local README for interface description. */
38 mysql_open(uschar *filename, uschar **errmsg)
40 return (void *)(1); /* Just return something non-null */
45 /*************************************************
47 *************************************************/
49 /* See local README for interface description. */
55 while ((cn = mysql_connections) != NULL)
57 mysql_connections = cn->next;
58 DEBUG(D_lookup) debug_printf("close MYSQL connection: %s\n", cn->server);
59 mysql_close(cn->handle);
65 /*************************************************
66 * Internal search function *
67 *************************************************/
69 /* This function is called from the find entry point to do the search for a
73 query the query string
74 server the server string
75 resultptr where to store the result
76 errmsg where to point an error message
77 defer_break TRUE if no more servers are to be tried after DEFER
78 do_cache set zero if data is changed
80 The server string is of the form "host/dbname/user/password". The host can be
81 host:port. This string is in a nextinlist temporary buffer, so can be
84 Returns: OK, FAIL, or DEFER
88 perform_mysql_search(const uschar *query, uschar *server, uschar **resultptr,
89 uschar **errmsg, BOOL *defer_break, uint *do_cache)
91 MYSQL *mysql_handle = NULL; /* Keep compilers happy */
92 MYSQL_RES *mysql_result = NULL;
93 MYSQL_ROW mysql_row_data;
98 unsigned int num_fields;
99 gstring * result = NULL;
100 mysql_connection *cn;
101 uschar *server_copy = NULL;
104 /* Disaggregate the parameters from the server argument. The order is host,
105 database, user, password. We can write to the string, since it is in a
106 nextinlist temporary buffer. The copy of the string that is used for caching
107 has the password removed. This copy is also used for debugging output. */
109 for (i = 3; i > 0; i--)
111 uschar *pp = Ustrrchr(server, '/');
114 *errmsg = string_sprintf("incomplete MySQL server data: %s",
115 (i == 3)? server : server_copy);
121 if (i == 3) server_copy = string_copy(server); /* sans password */
123 sdata[0] = server; /* What's left at the start */
125 /* See if we have a cached connection to the server */
127 for (cn = mysql_connections; cn; cn = cn->next)
128 if (Ustrcmp(cn->server, server_copy) == 0)
130 mysql_handle = cn->handle;
134 /* If no cached connection, we must set one up. Mysql allows for a host name
135 and port to be specified. It also allows the name of a Unix socket to be used.
136 Unfortunately, this contains slashes, but its use is expected to be rare, so
137 the rather cumbersome syntax shouldn't inconvenience too many people. We use
138 this: host:port(socket)[group] where all the parts are optional.
139 The "group" parameter specifies an option group from a MySQL option file. */
144 uschar *socket = NULL;
146 uschar *group = US"exim";
148 if ((p = Ustrchr(sdata[0], '[')))
152 while (*p && *p != ']') p++;
156 if ((p = Ustrchr(sdata[0], '(')))
160 while (*p && *p != ')') p++;
164 if ((p = Ustrchr(sdata[0], ':')))
170 if (Ustrchr(sdata[0], '/'))
172 *errmsg = string_sprintf("unexpected slash in MySQL server hostname: %s",
178 /* If the database is the empty string, set it NULL - the query must then
181 if (sdata[1][0] == 0) sdata[1] = NULL;
184 debug_printf("MYSQL new connection: host=%s port=%d socket=%s "
185 "database=%s user=%s\n", sdata[0], port, socket, sdata[1], sdata[2]);
187 /* Get store for a new handle, initialize it, and connect to the server */
189 mysql_handle = store_get(sizeof(MYSQL));
190 mysql_init(mysql_handle);
191 mysql_options(mysql_handle, MYSQL_READ_DEFAULT_GROUP, CS group);
192 if (mysql_real_connect(mysql_handle,
193 /* host user passwd database */
194 CS sdata[0], CS sdata[2], CS sdata[3], CS sdata[1],
195 port, CS socket, CLIENT_MULTI_RESULTS) == NULL)
197 *errmsg = string_sprintf("MYSQL connection failed: %s",
198 mysql_error(mysql_handle));
199 *defer_break = FALSE;
203 /* Add the connection to the cache */
205 cn = store_get(sizeof(mysql_connection));
206 cn->server = server_copy;
207 cn->handle = mysql_handle;
208 cn->next = mysql_connections;
209 mysql_connections = cn;
212 /* Else use a previously cached connection */
217 debug_printf("MYSQL using cached connection for %s\n", server_copy);
222 if (mysql_query(mysql_handle, CS query) != 0)
224 *errmsg = string_sprintf("MYSQL: query failed: %s\n",
225 mysql_error(mysql_handle));
226 *defer_break = FALSE;
230 /* Pick up the result. If the query was not of the type that returns data,
231 namely INSERT, UPDATE, or DELETE, an error occurs here. However, this situation
232 can be detected by calling mysql_field_count(). If its result is zero, no data
233 was expected (this is all explained clearly in the MySQL manual). In this case,
234 we return the number of rows affected by the command. In this event, we do NOT
235 want to cache the result; also the whole cache for the handle must be cleaned
236 up. Setting do_cache zero requests this. */
238 if ((mysql_result = mysql_use_result(mysql_handle)) == NULL)
240 if ( mysql_field_count(mysql_handle) == 0 )
242 DEBUG(D_lookup) debug_printf("MYSQL: query was not one that returns data\n");
243 result = string_cat(result,
244 string_sprintf("%d", mysql_affected_rows(mysql_handle)));
248 *errmsg = string_sprintf("MYSQL: lookup result failed: %s\n",
249 mysql_error(mysql_handle));
250 *defer_break = FALSE;
254 /* Find the number of fields returned. If this is one, we don't add field
255 names to the data. Otherwise we do. */
257 num_fields = mysql_num_fields(mysql_result);
259 /* Get the fields and construct the result string. If there is more than one
260 row, we insert '\n' between them. */
262 fields = mysql_fetch_fields(mysql_result);
264 while ((mysql_row_data = mysql_fetch_row(mysql_result)))
266 unsigned long *lengths = mysql_fetch_lengths(mysql_result);
269 result = string_catn(result, US"\n", 1);
273 if (mysql_row_data[0] != NULL) /* NULL value yields nothing */
275 result = string_catn(result, US mysql_row_data[0],
277 (void) string_from_gstring(result);
281 else for (i = 0; i < num_fields; i++)
282 result = lf_quote(US fields[i].name, US mysql_row_data[i], lengths[i], result);
285 /* more results? -1 = no, >0 = error, 0 = yes (keep looping)
286 This is needed because of the CLIENT_MULTI_RESULTS on mysql_real_connect(),
287 we don't expect any more results. */
289 while((i = mysql_next_result(mysql_handle)) >= 0) {
290 if(i == 0) { /* Just ignore more results */
291 DEBUG(D_lookup) debug_printf("MYSQL: got unexpected more results\n");
295 *errmsg = string_sprintf("MYSQL: lookup result error when checking for more results: %s\n",
296 mysql_error(mysql_handle));
300 /* If result is NULL then no data has been found and so we return FAIL.
301 Otherwise, we must terminate the string which has been built; string_cat()
302 always leaves enough room for a terminating zero. */
307 *errmsg = US"MYSQL: no data found";
311 (void) string_from_gstring(result);
312 store_reset(result->s + result->ptr + 1);
315 /* Get here by goto from various error checks and from the case where no data
316 was read (e.g. an update query). */
320 /* Free mysal store for any result that was got; don't close the connection, as
323 if (mysql_result) mysql_free_result(mysql_result);
325 /* Non-NULL result indicates a successful result */
329 *resultptr = result->s;
334 DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
335 return yield; /* FAIL or DEFER */
342 /*************************************************
344 *************************************************/
346 /* See local README for interface description. The handle and filename
347 arguments are not used. The code to loop through a list of servers while the
348 query is deferred with a retryable error is now in a separate function that is
349 shared with other SQL lookups. */
352 mysql_find(void *handle, uschar *filename, const uschar *query, int length,
353 uschar **result, uschar **errmsg, uint *do_cache)
355 return lf_sqlperform(US"MySQL", US"mysql_servers", mysql_servers, query,
356 result, errmsg, do_cache, perform_mysql_search);
361 /*************************************************
362 * Quote entry point *
363 *************************************************/
365 /* The only characters that need to be quoted (with backslash) are newline,
366 tab, carriage return, backspace, backslash itself, and the quote characters.
367 Percent, and underscore and not escaped. They are only special in contexts
368 where they can be wild cards, and this isn't usually the case for data inserted
369 from messages, since that isn't likely to be treated as a pattern of any kind.
370 Sadly, MySQL doesn't seem to behave like other programs. If you use something
371 like "where id="ab\%cd" it does not treat the string as "ab%cd". So you really
372 can't quote "on spec".
375 s the string to be quoted
376 opt additional option text or NULL if none
378 Returns: the processed string or NULL for a bad option
382 mysql_quote(uschar *s, uschar *opt)
389 if (opt != NULL) return NULL; /* No options recognized */
391 while ((c = *t++) != 0)
392 if (Ustrchr("\n\t\r\b\'\"\\", c) != NULL) count++;
394 if (count == 0) return s;
395 t = quoted = store_get(Ustrlen(s) + count + 1);
397 while ((c = *s++) != 0)
399 if (Ustrchr("\n\t\r\b\'\"\\", c) != NULL)
404 case '\n': *t++ = 'n';
406 case '\t': *t++ = 't';
408 case '\r': *t++ = 'r';
410 case '\b': *t++ = 'b';
424 /*************************************************
425 * Version reporting entry point *
426 *************************************************/
428 /* See local README for interface description. */
430 #include "../version.h"
433 mysql_version_report(FILE *f)
435 fprintf(f, "Library version: MySQL: Compile: %s [%s]\n"
437 MYSQL_SERVER_VERSION, MYSQL_COMPILATION_COMMENT,
438 mysql_get_client_info());
440 fprintf(f, " Exim version %s\n", EXIM_VERSION_STR);
444 /* These are the lookup_info blocks for this driver */
446 static lookup_info mysql_lookup_info = {
447 US"mysql", /* lookup name */
448 lookup_querystyle, /* query-style lookup */
449 mysql_open, /* open function */
450 NULL, /* no check function */
451 mysql_find, /* find function */
452 NULL, /* no close function */
453 mysql_tidy, /* tidy function */
454 mysql_quote, /* quoting function */
455 mysql_version_report /* version reporting */
459 #define mysql_lookup_module_info _lookup_module_info
462 static lookup_info *_lookup_list[] = { &mysql_lookup_info };
463 lookup_module_info mysql_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
465 /* End of lookups/mysql.c */