/*------------------------------------------------------------------------- * * adminpack.c * * * Copyright (c) 2002-2015, PostgreSQL Global Development Group * * Author: Andreas Pflug * * IDENTIFICATION * contrib/adminpack/adminpack.c * *------------------------------------------------------------------------- */ #include "postgres.h" #include #include #include #include "catalog/pg_type.h" #include "funcapi.h" #include "miscadmin.h" #include "postmaster/syslogger.h" #include "storage/fd.h" #include "utils/builtins.h" #include "utils/datetime.h" #ifdef WIN32 #ifdef rename #undef rename #endif #ifdef unlink #undef unlink #endif #endif PG_MODULE_MAGIC; PG_FUNCTION_INFO_V1(pg_file_write); PG_FUNCTION_INFO_V1(pg_file_rename); PG_FUNCTION_INFO_V1(pg_file_unlink); PG_FUNCTION_INFO_V1(pg_logdir_ls); /*----------------------- * some helper functions */ /* * Convert a "text" filename argument to C string, and check it's allowable. * * Filename may be absolute or relative to the DataDir, but we only allow * absolute paths that match DataDir or Log_directory. */ static char * convert_and_check_filename(text *arg, bool logAllowed) { char *filename = text_to_cstring(arg); canonicalize_path(filename); /* filename can change length here */ if (is_absolute_path(filename)) { /* Disallow '/a/b/data/..' */ if (path_contains_parent_reference(filename)) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("reference to parent directory (\"..\") not allowed")))); /* * Allow absolute paths if within DataDir or Log_directory, even * though Log_directory might be outside DataDir. */ if (!path_is_prefix_of_path(DataDir, filename) && (!logAllowed || !is_absolute_path(Log_directory) || !path_is_prefix_of_path(Log_directory, filename))) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("absolute path not allowed")))); } else if (!path_is_relative_and_below_cwd(filename)) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("path must be in or below the current directory")))); return filename; } /* * check for superuser, bark if not. */ static void requireSuperuser(void) { if (!superuser()) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("only superuser may access generic file functions")))); } /* ------------------------------------ * generic file handling functions */ Datum pg_file_write(PG_FUNCTION_ARGS) { FILE *f; char *filename; text *data; int64 count = 0; requireSuperuser(); filename = convert_and_check_filename(PG_GETARG_TEXT_P(0), false); data = PG_GETARG_TEXT_P(1); if (!PG_GETARG_BOOL(2)) { struct stat fst; if (stat(filename, &fst) >= 0) ereport(ERROR, (errcode(ERRCODE_DUPLICATE_FILE), errmsg("file \"%s\" exists", filename))); f = AllocateFile(filename, "wb"); } else f = AllocateFile(filename, "ab"); if (!f) ereport(ERROR, (errcode_for_file_access(), errmsg("could not open file \"%s\" for writing: %m", filename))); count = fwrite(VARDATA(data), 1, VARSIZE(data) - VARHDRSZ, f); if (count != VARSIZE(data) - VARHDRSZ || FreeFile(f)) ereport(ERROR, (errcode_for_file_access(), errmsg("could not write file \"%s\": %m", filename))); PG_RETURN_INT64(count); } Datum pg_file_rename(PG_FUNCTION_ARGS) { char *fn1, *fn2, *fn3; int rc; requireSuperuser(); if (PG_ARGISNULL(0) || PG_ARGISNULL(1)) PG_RETURN_NULL(); fn1 = convert_and_check_filename(PG_GETARG_TEXT_P(0), false); fn2 = convert_and_check_filename(PG_GETARG_TEXT_P(1), false); if (PG_ARGISNULL(2)) fn3 = NULL; else fn3 = convert_and_check_filename(PG_GETARG_TEXT_P(2), false); if (access(fn1, W_OK) < 0) { ereport(WARNING, (errcode_for_file_access(), errmsg("file \"%s\" is not accessible: %m", fn1))); PG_RETURN_BOOL(false); } if (fn3 && access(fn2, W_OK) < 0) { ereport(WARNING, (errcode_for_file_access(), errmsg("file \"%s\" is not accessible: %m", fn2))); PG_RETURN_BOOL(false); } rc = access(fn3 ? fn3 : fn2, W_OK); if (rc >= 0 || errno != ENOENT) { ereport(ERROR, (errcode(ERRCODE_DUPLICATE_FILE), errmsg("cannot rename to target file \"%s\"", fn3 ? fn3 : fn2))); } if (fn3) { if (rename(fn2, fn3) != 0) { ereport(ERROR, (errcode_for_file_access(), errmsg("could not rename \"%s\" to \"%s\": %m", fn2, fn3))); } if (rename(fn1, fn2) != 0) { ereport(WARNING, (errcode_for_file_access(), errmsg("could not rename \"%s\" to \"%s\": %m", fn1, fn2))); if (rename(fn3, fn2) != 0) { ereport(ERROR, (errcode_for_file_access(), errmsg("could not rename \"%s\" back to \"%s\": %m", fn3, fn2))); } else { ereport(ERROR, (errcode(ERRCODE_UNDEFINED_FILE), errmsg("renaming \"%s\" to \"%s\" was reverted", fn2, fn3))); } } } else if (rename(fn1, fn2) != 0) { ereport(ERROR, (errcode_for_file_access(), errmsg("could not rename \"%s\" to \"%s\": %m", fn1, fn2))); } PG_RETURN_BOOL(true); } Datum pg_file_unlink(PG_FUNCTION_ARGS) { char *filename; requireSuperuser(); filename = convert_and_check_filename(PG_GETARG_TEXT_P(0), false); if (access(filename, W_OK) < 0) { if (errno == ENOENT) PG_RETURN_BOOL(false); else ereport(ERROR, (errcode_for_file_access(), errmsg("file \"%s\" is not accessible: %m", filename))); } if (unlink(filename) < 0) { ereport(WARNING, (errcode_for_file_access(), errmsg("could not unlink file \"%s\": %m", filename))); PG_RETURN_BOOL(false); } PG_RETURN_BOOL(true); } Datum pg_logdir_ls(PG_FUNCTION_ARGS) { ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; bool randomAccess; TupleDesc tupdesc; Tuplestorestate *tupstore; AttInMetadata *attinmeta; DIR *dirdesc; struct dirent *de; MemoryContext oldcontext; if (!superuser()) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("only superuser can list the log directory")))); if (strcmp(Log_filename, "postgresql-%Y-%m-%d_%H%M%S.log") != 0) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("the log_filename parameter must equal 'postgresql-%%Y-%%m-%%d_%%H%%M%%S.log'"))); /* check to see if caller supports us returning a tuplestore */ if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo)) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("set-valued function called in context that cannot accept a set"))); if (!(rsinfo->allowedModes & SFRM_Materialize)) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("materialize mode required, but it is not allowed in this context"))); /* The tupdesc and tuplestore must be created in ecxt_per_query_memory */ oldcontext = MemoryContextSwitchTo(rsinfo->econtext->ecxt_per_query_memory); tupdesc = CreateTemplateTupleDesc(2, false); TupleDescInitEntry(tupdesc, (AttrNumber) 1, "starttime", TIMESTAMPOID, -1, 0); TupleDescInitEntry(tupdesc, (AttrNumber) 2, "filename", TEXTOID, -1, 0); randomAccess = (rsinfo->allowedModes & SFRM_Materialize_Random) != 0; tupstore = tuplestore_begin_heap(randomAccess, false, work_mem); rsinfo->returnMode = SFRM_Materialize; rsinfo->setResult = tupstore; rsinfo->setDesc = tupdesc; MemoryContextSwitchTo(oldcontext); attinmeta = TupleDescGetAttInMetadata(tupdesc); dirdesc = AllocateDir(Log_directory); while ((de = ReadDir(dirdesc, Log_directory)) != NULL) { char *values[2]; HeapTuple tuple; char timestampbuf[32]; char *field[MAXDATEFIELDS]; char lowstr[MAXDATELEN + 1]; int dtype; int nf, ftype[MAXDATEFIELDS]; fsec_t fsec; int tz = 0; struct pg_tm date; /* * Default format: postgresql-YYYY-MM-DD_HHMMSS.log */ if (strlen(de->d_name) != 32 || strncmp(de->d_name, "postgresql-", 11) != 0 || de->d_name[21] != '_' || strcmp(de->d_name + 28, ".log") != 0) continue; /* extract timestamp portion of filename */ strcpy(timestampbuf, de->d_name + 11); timestampbuf[17] = '\0'; /* parse and decode expected timestamp to verify it's OK format */ if (ParseDateTime(timestampbuf, lowstr, MAXDATELEN, field, ftype, MAXDATEFIELDS, &nf)) continue; if (DecodeDateTime(field, ftype, nf, &dtype, &date, &fsec, &tz)) continue; /* Seems the timestamp is OK; prepare and return tuple */ values[0] = timestampbuf; values[1] = psprintf("%s/%s", Log_directory, de->d_name); tuple = BuildTupleFromCStrings(attinmeta, values); tuplestore_puttuple(tupstore, tuple); } FreeDir(dirdesc); return (Datum) 0; }