1 /*-------------------------------------------------------------------------
2 *
3 * adminpack.c
4 *
5 *
6 * Copyright (c) 2002-2016, PostgreSQL Global Development Group
7 *
8 * Author: Andreas Pflug <pgadmin@pse-consulting.de>
9 *
10 * IDENTIFICATION
11 * contrib/adminpack/adminpack.c
12 *
13 *-------------------------------------------------------------------------
14 */
15 #include "postgres.h"
16
17 #include <sys/file.h>
18 #include <sys/stat.h>
19 #include <unistd.h>
20
21 #include "catalog/pg_type.h"
22 #include "funcapi.h"
23 #include "miscadmin.h"
24 #include "postmaster/syslogger.h"
25 #include "storage/fd.h"
26 #include "utils/builtins.h"
27 #include "utils/datetime.h"
28
29
30 #ifdef WIN32
31
32 #ifdef rename
33 #undef rename
34 #endif
35
36 #ifdef unlink
37 #undef unlink
38 #endif
39 #endif
40
41 PG_MODULE_MAGIC;
42
43 PG_FUNCTION_INFO_V1(pg_file_write);
44 PG_FUNCTION_INFO_V1(pg_file_rename);
45 PG_FUNCTION_INFO_V1(pg_file_unlink);
46 PG_FUNCTION_INFO_V1(pg_logdir_ls);
47
48
49 /*-----------------------
50 * some helper functions
51 */
52
53 /*
54 * Convert a "text" filename argument to C string, and check it's allowable.
55 *
56 * Filename may be absolute or relative to the DataDir, but we only allow
57 * absolute paths that match DataDir or Log_directory.
58 */
59 static char *
convert_and_check_filename(text * arg,bool logAllowed)60 convert_and_check_filename(text *arg, bool logAllowed)
61 {
62 char *filename = text_to_cstring(arg);
63
64 canonicalize_path(filename); /* filename can change length here */
65
66 if (is_absolute_path(filename))
67 {
68 /* Disallow '/a/b/data/..' */
69 if (path_contains_parent_reference(filename))
70 ereport(ERROR,
71 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
72 (errmsg("reference to parent directory (\"..\") not allowed"))));
73
74 /*
75 * Allow absolute paths if within DataDir or Log_directory, even
76 * though Log_directory might be outside DataDir.
77 */
78 if (!path_is_prefix_of_path(DataDir, filename) &&
79 (!logAllowed || !is_absolute_path(Log_directory) ||
80 !path_is_prefix_of_path(Log_directory, filename)))
81 ereport(ERROR,
82 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
83 (errmsg("absolute path not allowed"))));
84 }
85 else if (!path_is_relative_and_below_cwd(filename))
86 ereport(ERROR,
87 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
88 (errmsg("path must be in or below the current directory"))));
89
90 return filename;
91 }
92
93
94 /*
95 * check for superuser, bark if not.
96 */
97 static void
requireSuperuser(void)98 requireSuperuser(void)
99 {
100 if (!superuser())
101 ereport(ERROR,
102 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
103 (errmsg("only superuser may access generic file functions"))));
104 }
105
106
107
108 /* ------------------------------------
109 * generic file handling functions
110 */
111
112 Datum
pg_file_write(PG_FUNCTION_ARGS)113 pg_file_write(PG_FUNCTION_ARGS)
114 {
115 FILE *f;
116 char *filename;
117 text *data;
118 int64 count = 0;
119
120 requireSuperuser();
121
122 filename = convert_and_check_filename(PG_GETARG_TEXT_P(0), false);
123 data = PG_GETARG_TEXT_P(1);
124
125 if (!PG_GETARG_BOOL(2))
126 {
127 struct stat fst;
128
129 if (stat(filename, &fst) >= 0)
130 ereport(ERROR,
131 (errcode(ERRCODE_DUPLICATE_FILE),
132 errmsg("file \"%s\" exists", filename)));
133
134 f = AllocateFile(filename, "wb");
135 }
136 else
137 f = AllocateFile(filename, "ab");
138
139 if (!f)
140 ereport(ERROR,
141 (errcode_for_file_access(),
142 errmsg("could not open file \"%s\" for writing: %m",
143 filename)));
144
145 count = fwrite(VARDATA(data), 1, VARSIZE(data) - VARHDRSZ, f);
146 if (count != VARSIZE(data) - VARHDRSZ || FreeFile(f))
147 ereport(ERROR,
148 (errcode_for_file_access(),
149 errmsg("could not write file \"%s\": %m", filename)));
150
151 PG_RETURN_INT64(count);
152 }
153
154
155 Datum
pg_file_rename(PG_FUNCTION_ARGS)156 pg_file_rename(PG_FUNCTION_ARGS)
157 {
158 char *fn1,
159 *fn2,
160 *fn3;
161 int rc;
162
163 requireSuperuser();
164
165 if (PG_ARGISNULL(0) || PG_ARGISNULL(1))
166 PG_RETURN_NULL();
167
168 fn1 = convert_and_check_filename(PG_GETARG_TEXT_P(0), false);
169 fn2 = convert_and_check_filename(PG_GETARG_TEXT_P(1), false);
170 if (PG_ARGISNULL(2))
171 fn3 = NULL;
172 else
173 fn3 = convert_and_check_filename(PG_GETARG_TEXT_P(2), false);
174
175 if (access(fn1, W_OK) < 0)
176 {
177 ereport(WARNING,
178 (errcode_for_file_access(),
179 errmsg("file \"%s\" is not accessible: %m", fn1)));
180
181 PG_RETURN_BOOL(false);
182 }
183
184 if (fn3 && access(fn2, W_OK) < 0)
185 {
186 ereport(WARNING,
187 (errcode_for_file_access(),
188 errmsg("file \"%s\" is not accessible: %m", fn2)));
189
190 PG_RETURN_BOOL(false);
191 }
192
193 rc = access(fn3 ? fn3 : fn2, W_OK);
194 if (rc >= 0 || errno != ENOENT)
195 {
196 ereport(ERROR,
197 (errcode(ERRCODE_DUPLICATE_FILE),
198 errmsg("cannot rename to target file \"%s\"",
199 fn3 ? fn3 : fn2)));
200 }
201
202 if (fn3)
203 {
204 if (rename(fn2, fn3) != 0)
205 {
206 ereport(ERROR,
207 (errcode_for_file_access(),
208 errmsg("could not rename \"%s\" to \"%s\": %m",
209 fn2, fn3)));
210 }
211 if (rename(fn1, fn2) != 0)
212 {
213 ereport(WARNING,
214 (errcode_for_file_access(),
215 errmsg("could not rename \"%s\" to \"%s\": %m",
216 fn1, fn2)));
217
218 if (rename(fn3, fn2) != 0)
219 {
220 ereport(ERROR,
221 (errcode_for_file_access(),
222 errmsg("could not rename \"%s\" back to \"%s\": %m",
223 fn3, fn2)));
224 }
225 else
226 {
227 ereport(ERROR,
228 (errcode(ERRCODE_UNDEFINED_FILE),
229 errmsg("renaming \"%s\" to \"%s\" was reverted",
230 fn2, fn3)));
231 }
232 }
233 }
234 else if (rename(fn1, fn2) != 0)
235 {
236 ereport(ERROR,
237 (errcode_for_file_access(),
238 errmsg("could not rename \"%s\" to \"%s\": %m", fn1, fn2)));
239 }
240
241 PG_RETURN_BOOL(true);
242 }
243
244
245 Datum
pg_file_unlink(PG_FUNCTION_ARGS)246 pg_file_unlink(PG_FUNCTION_ARGS)
247 {
248 char *filename;
249
250 requireSuperuser();
251
252 filename = convert_and_check_filename(PG_GETARG_TEXT_P(0), false);
253
254 if (access(filename, W_OK) < 0)
255 {
256 if (errno == ENOENT)
257 PG_RETURN_BOOL(false);
258 else
259 ereport(ERROR,
260 (errcode_for_file_access(),
261 errmsg("file \"%s\" is not accessible: %m", filename)));
262 }
263
264 if (unlink(filename) < 0)
265 {
266 ereport(WARNING,
267 (errcode_for_file_access(),
268 errmsg("could not unlink file \"%s\": %m", filename)));
269
270 PG_RETURN_BOOL(false);
271 }
272 PG_RETURN_BOOL(true);
273 }
274
275
276 Datum
pg_logdir_ls(PG_FUNCTION_ARGS)277 pg_logdir_ls(PG_FUNCTION_ARGS)
278 {
279 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
280 bool randomAccess;
281 TupleDesc tupdesc;
282 Tuplestorestate *tupstore;
283 AttInMetadata *attinmeta;
284 DIR *dirdesc;
285 struct dirent *de;
286 MemoryContext oldcontext;
287
288 if (!superuser())
289 ereport(ERROR,
290 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
291 (errmsg("only superuser can list the log directory"))));
292
293 if (strcmp(Log_filename, "postgresql-%Y-%m-%d_%H%M%S.log") != 0)
294 ereport(ERROR,
295 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
296 errmsg("the log_filename parameter must equal 'postgresql-%%Y-%%m-%%d_%%H%%M%%S.log'")));
297
298 /* check to see if caller supports us returning a tuplestore */
299 if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
300 ereport(ERROR,
301 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
302 errmsg("set-valued function called in context that cannot accept a set")));
303 if (!(rsinfo->allowedModes & SFRM_Materialize))
304 ereport(ERROR,
305 (errcode(ERRCODE_SYNTAX_ERROR),
306 errmsg("materialize mode required, but it is not allowed in this context")));
307
308 /* The tupdesc and tuplestore must be created in ecxt_per_query_memory */
309 oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory);
310
311 tupdesc = CreateTemplateTupleDesc(2, false);
312 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "starttime",
313 TIMESTAMPOID, -1, 0);
314 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "filename",
315 TEXTOID, -1, 0);
316
317 randomAccess = (rsinfo->allowedModes & SFRM_Materialize_Random) != 0;
318 tupstore = tuplestore_begin_heap(randomAccess, false, work_mem);
319 rsinfo->returnMode = SFRM_Materialize;
320 rsinfo->setResult = tupstore;
321 rsinfo->setDesc = tupdesc;
322
323 MemoryContextSwitchTo(oldcontext);
324
325 attinmeta = TupleDescGetAttInMetadata(tupdesc);
326
327 dirdesc = AllocateDir(Log_directory);
328 while ((de = ReadDir(dirdesc, Log_directory)) != NULL)
329 {
330 char *values[2];
331 HeapTuple tuple;
332 char timestampbuf[32];
333 char *field[MAXDATEFIELDS];
334 char lowstr[MAXDATELEN + 1];
335 int dtype;
336 int nf,
337 ftype[MAXDATEFIELDS];
338 fsec_t fsec;
339 int tz = 0;
340 struct pg_tm date;
341
342 /*
343 * Default format: postgresql-YYYY-MM-DD_HHMMSS.log
344 */
345 if (strlen(de->d_name) != 32
346 || strncmp(de->d_name, "postgresql-", 11) != 0
347 || de->d_name[21] != '_'
348 || strcmp(de->d_name + 28, ".log") != 0)
349 continue;
350
351 /* extract timestamp portion of filename */
352 strcpy(timestampbuf, de->d_name + 11);
353 timestampbuf[17] = '\0';
354
355 /* parse and decode expected timestamp to verify it's OK format */
356 if (ParseDateTime(timestampbuf, lowstr, MAXDATELEN, field, ftype, MAXDATEFIELDS, &nf))
357 continue;
358
359 if (DecodeDateTime(field, ftype, nf, &dtype, &date, &fsec, &tz))
360 continue;
361
362 /* Seems the timestamp is OK; prepare and return tuple */
363
364 values[0] = timestampbuf;
365 values[1] = psprintf("%s/%s", Log_directory, de->d_name);
366
367 tuple = BuildTupleFromCStrings(attinmeta, values);
368
369 tuplestore_puttuple(tupstore, tuple);
370 }
371
372 FreeDir(dirdesc);
373 return (Datum) 0;
374 }
375