postgresql/contrib/adminpack/adminpack.c
Stephen Frost c9c41c7a33 Rename Default Roles to Predefined Roles
The term 'default roles' wasn't quite apt as these roles aren't able to
be modified or removed after installation, so rename them to be
'Predefined Roles' instead, adding an entry into the newly added
Obsolete Appendix to help users of current releases find the new
documentation.

Bruce Momjian and Stephen Frost

Discussion: https://postgr.es/m/157742545062.1149.11052653770497832538%40wrigleys.postgresql.org
and https://www.postgresql.org/message-id/20201120211304.GG16415@tamriel.snowman.net
2021-04-01 15:32:06 -04:00

596 lines
14 KiB
C

/*-------------------------------------------------------------------------
*
* adminpack.c
*
*
* Copyright (c) 2002-2021, PostgreSQL Global Development Group
*
* Author: Andreas Pflug <pgadmin@pse-consulting.de>
*
* IDENTIFICATION
* contrib/adminpack/adminpack.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <sys/file.h>
#include <sys/stat.h>
#include <unistd.h>
#include "catalog/pg_authid.h"
#include "catalog/pg_type.h"
#include "funcapi.h"
#include "miscadmin.h"
#include "postmaster/syslogger.h"
#include "storage/fd.h"
#include "utils/acl.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_write_v1_1);
PG_FUNCTION_INFO_V1(pg_file_sync);
PG_FUNCTION_INFO_V1(pg_file_rename);
PG_FUNCTION_INFO_V1(pg_file_rename_v1_1);
PG_FUNCTION_INFO_V1(pg_file_unlink);
PG_FUNCTION_INFO_V1(pg_file_unlink_v1_1);
PG_FUNCTION_INFO_V1(pg_logdir_ls);
PG_FUNCTION_INFO_V1(pg_logdir_ls_v1_1);
static int64 pg_file_write_internal(text *file, text *data, bool replace);
static bool pg_file_rename_internal(text *file1, text *file2, text *file3);
static Datum pg_logdir_ls_internal(FunctionCallInfo fcinfo);
/*-----------------------
* 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.
*/
static char *
convert_and_check_filename(text *arg)
{
char *filename = text_to_cstring(arg);
canonicalize_path(filename); /* filename can change length here */
/*
* Members of the 'pg_write_server_files' role are allowed to access any
* files on the server as the PG user, so no need to do any further checks
* here.
*/
if (is_member_of_role(GetUserId(), ROLE_PG_WRITE_SERVER_FILES))
return filename;
/*
* User isn't a member of the pg_write_server_files role, so check if it's
* allowable
*/
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 */
if (!path_is_prefix_of_path(DataDir, 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")));
}
/* ------------------------------------
* pg_file_write - old version
*
* The superuser() check here must be kept as the library might be upgraded
* without the extension being upgraded, meaning that in pre-1.1 installations
* these functions could be called by any user.
*/
Datum
pg_file_write(PG_FUNCTION_ARGS)
{
text *file = PG_GETARG_TEXT_PP(0);
text *data = PG_GETARG_TEXT_PP(1);
bool replace = PG_GETARG_BOOL(2);
int64 count = 0;
requireSuperuser();
count = pg_file_write_internal(file, data, replace);
PG_RETURN_INT64(count);
}
/* ------------------------------------
* pg_file_write_v1_1 - Version 1.1
*
* As of adminpack version 1.1, we no longer need to check if the user
* is a superuser because we REVOKE EXECUTE on the function from PUBLIC.
* Users can then grant access to it based on their policies.
*
* Otherwise identical to pg_file_write (above).
*/
Datum
pg_file_write_v1_1(PG_FUNCTION_ARGS)
{
text *file = PG_GETARG_TEXT_PP(0);
text *data = PG_GETARG_TEXT_PP(1);
bool replace = PG_GETARG_BOOL(2);
int64 count = 0;
count = pg_file_write_internal(file, data, replace);
PG_RETURN_INT64(count);
}
/* ------------------------------------
* pg_file_write_internal - Workhorse for pg_file_write functions.
*
* This handles the actual work for pg_file_write.
*/
static int64
pg_file_write_internal(text *file, text *data, bool replace)
{
FILE *f;
char *filename;
int64 count = 0;
filename = convert_and_check_filename(file);
if (!replace)
{
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_ANY(data), 1, VARSIZE_ANY_EXHDR(data), f);
if (count != VARSIZE_ANY_EXHDR(data) || FreeFile(f))
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not write file \"%s\": %m", filename)));
return (count);
}
/* ------------------------------------
* pg_file_sync
*
* We REVOKE EXECUTE on the function from PUBLIC.
* Users can then grant access to it based on their policies.
*/
Datum
pg_file_sync(PG_FUNCTION_ARGS)
{
char *filename;
struct stat fst;
filename = convert_and_check_filename(PG_GETARG_TEXT_PP(0));
if (stat(filename, &fst) < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not stat file \"%s\": %m", filename)));
fsync_fname_ext(filename, S_ISDIR(fst.st_mode), false, ERROR);
PG_RETURN_VOID();
}
/* ------------------------------------
* pg_file_rename - old version
*
* The superuser() check here must be kept as the library might be upgraded
* without the extension being upgraded, meaning that in pre-1.1 installations
* these functions could be called by any user.
*/
Datum
pg_file_rename(PG_FUNCTION_ARGS)
{
text *file1;
text *file2;
text *file3;
bool result;
requireSuperuser();
if (PG_ARGISNULL(0) || PG_ARGISNULL(1))
PG_RETURN_NULL();
file1 = PG_GETARG_TEXT_PP(0);
file2 = PG_GETARG_TEXT_PP(1);
if (PG_ARGISNULL(2))
file3 = NULL;
else
file3 = PG_GETARG_TEXT_PP(2);
result = pg_file_rename_internal(file1, file2, file3);
PG_RETURN_BOOL(result);
}
/* ------------------------------------
* pg_file_rename_v1_1 - Version 1.1
*
* As of adminpack version 1.1, we no longer need to check if the user
* is a superuser because we REVOKE EXECUTE on the function from PUBLIC.
* Users can then grant access to it based on their policies.
*
* Otherwise identical to pg_file_write (above).
*/
Datum
pg_file_rename_v1_1(PG_FUNCTION_ARGS)
{
text *file1;
text *file2;
text *file3;
bool result;
if (PG_ARGISNULL(0) || PG_ARGISNULL(1))
PG_RETURN_NULL();
file1 = PG_GETARG_TEXT_PP(0);
file2 = PG_GETARG_TEXT_PP(1);
if (PG_ARGISNULL(2))
file3 = NULL;
else
file3 = PG_GETARG_TEXT_PP(2);
result = pg_file_rename_internal(file1, file2, file3);
PG_RETURN_BOOL(result);
}
/* ------------------------------------
* pg_file_rename_internal - Workhorse for pg_file_rename functions.
*
* This handles the actual work for pg_file_rename.
*/
static bool
pg_file_rename_internal(text *file1, text *file2, text *file3)
{
char *fn1,
*fn2,
*fn3;
int rc;
fn1 = convert_and_check_filename(file1);
fn2 = convert_and_check_filename(file2);
if (file3 == NULL)
fn3 = NULL;
else
fn3 = convert_and_check_filename(file3);
if (access(fn1, W_OK) < 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("file \"%s\" is not accessible: %m", fn1)));
return false;
}
if (fn3 && access(fn2, W_OK) < 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("file \"%s\" is not accessible: %m", fn2)));
return 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)));
}
return true;
}
/* ------------------------------------
* pg_file_unlink - old version
*
* The superuser() check here must be kept as the library might be upgraded
* without the extension being upgraded, meaning that in pre-1.1 installations
* these functions could be called by any user.
*/
Datum
pg_file_unlink(PG_FUNCTION_ARGS)
{
char *filename;
requireSuperuser();
filename = convert_and_check_filename(PG_GETARG_TEXT_PP(0));
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);
}
/* ------------------------------------
* pg_file_unlink_v1_1 - Version 1.1
*
* As of adminpack version 1.1, we no longer need to check if the user
* is a superuser because we REVOKE EXECUTE on the function from PUBLIC.
* Users can then grant access to it based on their policies.
*
* Otherwise identical to pg_file_unlink (above).
*/
Datum
pg_file_unlink_v1_1(PG_FUNCTION_ARGS)
{
char *filename;
filename = convert_and_check_filename(PG_GETARG_TEXT_PP(0));
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);
}
/* ------------------------------------
* pg_logdir_ls - Old version
*
* The superuser() check here must be kept as the library might be upgraded
* without the extension being upgraded, meaning that in pre-1.1 installations
* these functions could be called by any user.
*/
Datum
pg_logdir_ls(PG_FUNCTION_ARGS)
{
if (!superuser())
ereport(ERROR,
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("only superuser can list the log directory")));
return (pg_logdir_ls_internal(fcinfo));
}
/* ------------------------------------
* pg_logdir_ls_v1_1 - Version 1.1
*
* As of adminpack version 1.1, we no longer need to check if the user
* is a superuser because we REVOKE EXECUTE on the function from PUBLIC.
* Users can then grant access to it based on their policies.
*
* Otherwise identical to pg_logdir_ls (above).
*/
Datum
pg_logdir_ls_v1_1(PG_FUNCTION_ARGS)
{
return (pg_logdir_ls_internal(fcinfo));
}
static Datum
pg_logdir_ls_internal(FunctionCallInfo fcinfo)
{
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
bool randomAccess;
TupleDesc tupdesc;
Tuplestorestate *tupstore;
AttInMetadata *attinmeta;
DIR *dirdesc;
struct dirent *de;
MemoryContext oldcontext;
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);
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;
}