/*------------------------------------------------------------------------- * * adminpack.c * * * Copyright (c) 2002-2010, 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; Datum pg_file_write(PG_FUNCTION_ARGS); Datum pg_file_rename(PG_FUNCTION_ARGS); Datum pg_file_unlink(PG_FUNCTION_ARGS); Datum pg_logdir_ls(PG_FUNCTION_ARGS); 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); typedef struct { char *location; DIR *dirdesc; } directory_fctx; /*----------------------- * 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 */ /* Disallow ".." in the path */ if (path_contains_parent_reference(filename)) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("reference to parent directory (\"..\") not allowed")))); if (is_absolute_path(filename)) { /* Allow absolute references within DataDir */ if (path_is_prefix_of_path(DataDir, filename)) return filename; /* The log directory might be outside our datadir, but allow it */ if (logAllowed && is_absolute_path(Log_directory) && path_is_prefix_of_path(Log_directory, filename)) return filename; ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), (errmsg("absolute path not allowed")))); return NULL; /* keep compiler quiet */ } else { 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_DUPLICATE_FILE, errmsg("file \"%s\" exists", filename))); f = fopen(filename, "wb"); } else f = fopen(filename, "ab"); if (!f) ereport(ERROR, (errcode_for_file_access(), errmsg("could not open file \"%s\" for writing: %m", filename))); if (VARSIZE(data) != 0) { count = fwrite(VARDATA(data), 1, VARSIZE(data) - VARHDRSZ, f); if (count != VARSIZE(data) - VARHDRSZ) ereport(ERROR, (errcode_for_file_access(), errmsg("could not write file \"%s\": %m", filename))); } fclose(f); 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 = 0; 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, 2); if (rc >= 0 || errno != ENOENT) { ereport(ERROR, (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_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) { FuncCallContext *funcctx; struct dirent *de; directory_fctx *fctx; 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'")))); if (SRF_IS_FIRSTCALL()) { MemoryContext oldcontext; TupleDesc tupdesc; funcctx = SRF_FIRSTCALL_INIT(); oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx); fctx = palloc(sizeof(directory_fctx)); tupdesc = CreateTemplateTupleDesc(2, false); TupleDescInitEntry(tupdesc, (AttrNumber) 1, "starttime", TIMESTAMPOID, -1, 0); TupleDescInitEntry(tupdesc, (AttrNumber) 2, "filename", TEXTOID, -1, 0); funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc); fctx->location = pstrdup(Log_directory); fctx->dirdesc = AllocateDir(fctx->location); if (!fctx->dirdesc) ereport(ERROR, (errcode_for_file_access(), errmsg("could not read directory \"%s\": %m", fctx->location))); funcctx->user_fctx = fctx; MemoryContextSwitchTo(oldcontext); } funcctx = SRF_PERCALL_SETUP(); fctx = (directory_fctx *) funcctx->user_fctx; while ((de = ReadDir(fctx->dirdesc, fctx->location)) != 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] = palloc(strlen(fctx->location) + strlen(de->d_name) + 2); sprintf(values[1], "%s/%s", fctx->location, de->d_name); tuple = BuildTupleFromCStrings(funcctx->attinmeta, values); SRF_RETURN_NEXT(funcctx, HeapTupleGetDatum(tuple)); } FreeDir(fctx->dirdesc); SRF_RETURN_DONE(funcctx); }