/*
* Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/*
* lib/krb5/rcache/rc_io.c
*
* This file of the Kerberos V5 software is derived from public-domain code
* contributed by Daniel J. Bernstein, <brnstnd@acf10.nyu.edu>.
*
*/
/*
* I/O functions for the replay cache default implementation.
*/
#if defined(_WIN32)
# define PATH_SEPARATOR "\\"
#else
# define PATH_SEPARATOR "/"
#endif
#define KRB5_RC_VNO 0x0501 /* krb5, rcache v 1 */
#include "k5-int.h"
#include <stdio.h> /* for P_tmpdir */
#include <sys/types.h>
#include <unistd.h>
#include <syslog.h> /* SUNW */
#include <locale.h> /* Solaris Kerberos */
#include "rc_base.h"
#include "rc_file.h"
#include "rc_io.h"
#ifndef O_BINARY
#define O_BINARY 0
#endif
#ifdef HAVE_NETINET_IN_H
#if !defined(_WINSOCKAPI_)
#include <netinet/in.h>
#endif
#else
#error find some way to use net-byte-order file version numbers.
#endif
/* Solaris Kerberos */
#define FREE_RC(x) ((void) free((char *) (x)))
#define UNIQUE getpid() /* hopefully unique number */
#define GETDIR (dir = getdir(), dirlen = strlen(dir) + sizeof(PATH_SEPARATOR) - 1)
static char *
getdir(void)
{
char *dir;
#if defined(_WIN32)
if (!(dir = getenv("TEMP")))
if (!(dir = getenv("TMP")))
dir = "C:";
#else
/* Solaris Kerberos */
if (geteuid() == 0)
dir = "/var/krb5/rcache/root";
else
dir = "/var/krb5/rcache";
#endif
return dir;
}
krb5_error_code
krb5_rc_io_creat(krb5_context context, krb5_rc_iostuff *d, char **fn)
{
char *c;
krb5_int16 rc_vno = htons(KRB5_RC_VNO);
krb5_error_code retval = 0;
int do_not_unlink = 0;
char *dir;
size_t dirlen;
GETDIR;
if (fn && *fn)
{
/* Solaris Kerberos */
if (*fn[0] == '/') {
d->fn = strdup(*fn);
if (d->fn == NULL)
return (KRB5_RC_IO_MALLOC);
} else {
if (!(d->fn = malloc(strlen(*fn) + dirlen + 1)))
return KRB5_RC_IO_MALLOC;
(void) strcpy(d->fn, dir);
(void) strcat(d->fn, PATH_SEPARATOR);
(void) strcat(d->fn, *fn);
}
d->fd = THREEPARAMOPEN(d->fn, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL |
O_BINARY, 0600);
}
else
{
/* %d is max 11 digits (-, 10 digits of 32-bit number)
* 11 + /krb5_RC + aaa = 24, +6 for slop */
if (!(d->fn = malloc(30 + dirlen)))
return KRB5_RC_IO_MALLOC;
if (fn)
if (!(*fn = malloc(35))) {
FREE_RC(d->fn);
return KRB5_RC_IO_MALLOC;
}
(void) sprintf(d->fn, "%s%skrb5_RC%d", dir, PATH_SEPARATOR,
(int) UNIQUE);
c = d->fn + strlen(d->fn);
(void) strcpy(c, "aaa");
while ((d->fd = THREEPARAMOPEN(d->fn, O_WRONLY | O_CREAT | O_TRUNC |
O_EXCL | O_BINARY, 0600)) == -1)
{
if ((c[2]++) == 'z')
{
c[2] = 'a';
if ((c[1]++) == 'z')
{
c[1] = 'a';
if ((c[0]++) == 'z')
break; /* sigh */
}
}
}
if (fn)
(void) strcpy(*fn, d->fn + dirlen);
}
if (d->fd == -1)
{
switch(errno)
{
case EFBIG:
#ifdef EDQUOT
case EDQUOT:
#endif
case ENOSPC:
retval = KRB5_RC_IO_SPACE;
goto cleanup;
case EIO:
retval = KRB5_RC_IO_IO;
goto cleanup;
case EPERM:
case EACCES:
case EROFS:
case EEXIST:
retval = KRB5_RC_IO_PERM;
krb5_set_error_message(context, retval,
dgettext(TEXT_DOMAIN,
"Cannot create replay cache %s: %s"),
d->fn ? d->fn : "<null>",
strerror(errno));
do_not_unlink = 1;
goto cleanup;
default:
retval = KRB5_RC_IO_UNKNOWN;
krb5_set_error_message(context, retval,
dgettext(TEXT_DOMAIN,
"Cannot create replay cache %s: %s"),
d->fn ? d->fn : "<null>",
strerror(errno));
goto cleanup;
}
}
retval = krb5_rc_io_write(context, d, (krb5_pointer)&rc_vno,
sizeof(rc_vno));
if (retval)
goto cleanup;
retval = krb5_rc_io_sync(context, d);
cleanup:
if (retval) {
if (d->fn) {
if (!do_not_unlink)
(void) unlink(d->fn);
FREE_RC(d->fn);
d->fn = NULL;
}
if (d->fd != -1) {
(void) close(d->fd);
}
}
return retval;
}
static krb5_error_code
krb5_rc_io_open_internal(krb5_context context, krb5_rc_iostuff *d, char *fn,
char* full_pathname)
{
krb5_int16 rc_vno;
krb5_error_code retval = 0;
int do_not_unlink = 1;
struct stat lstatb, fstatb;
int use_errno = 0;
char *dir;
size_t dirlen;
GETDIR;
if (fn[0] == '/') {
d->fn = strdup(fn);
if (d->fn == NULL)
return (KRB5_RC_IO_MALLOC);
} else {
if (!(d->fn = malloc(strlen(fn) + dirlen + 1)))
return KRB5_RC_IO_MALLOC;
(void) strcpy(d->fn, dir);
(void) strcat(d->fn, PATH_SEPARATOR);
(void) strcat(d->fn, fn);
}
/* Solaris: BEGIN made changes to be safer and better code structure */
if ((d->fd = THREEPARAMOPEN(d->fn, O_RDWR|O_BINARY, 0600)) == -1) {
use_errno = 1;
goto cleanup;
}
do_not_unlink = 0;
if (fstat(d->fd, &fstatb) == 0) {
#ifndef NO_USERID
uid_t me;
me = geteuid();
/* must be owned by this user, to prevent some security problems with
* other users modifying replay cache stuff and must be a regular file
*/
if ((fstatb.st_uid != me) || ((fstatb.st_mode & S_IFMT) != S_IFREG)) {
retval = KRB5_RC_IO_PERM;
goto cleanup;
}
#else
/* make sure the rcache is a regular file */
if (((fstatb.st_mode & S_IFMT) != S_IFREG)) {
retval = KRB5_RC_IO_PERM;
goto cleanup;
}
#endif
if (lstat(d->fn, &lstatb) == 0) {
/* Make sure fstat() and lstat() have accessed the same file */
if ((lstatb.st_ino != fstatb.st_ino) ||
(lstatb.st_dev != fstatb.st_dev)) {
retval = KRB5_RC_IO_PERM;
goto cleanup;
}
if ((lstatb.st_mode & S_IFMT) == S_IFLNK) {
/* if we accessed the rcache via a symlink, bail out */
syslog(LOG_ERR, "Error, krb replay cache %s is a symlink "
"and should be removed.\n", d->fn);
retval = KRB5_RC_IO_PERM;
goto cleanup;
}
}
else {
use_errno = 1;
goto cleanup;
}
}
else {
use_errno = 1;
goto cleanup;
}
do_not_unlink = 0;
retval = krb5_rc_io_read(context, d, (krb5_pointer) &rc_vno,
sizeof(rc_vno));
if (retval)
goto cleanup;
if (ntohs(rc_vno) != KRB5_RC_VNO)
retval = KRB5_RCACHE_BADVNO;
cleanup:
if (use_errno) {
switch(errno)
{
case EFBIG:
#ifdef EDQUOT
case EDQUOT:
#endif
case ENOSPC:
retval = KRB5_RC_IO_SPACE;
break;
case EIO:
retval = KRB5_RC_IO_IO;
break;
case EPERM:
case EACCES:
case EROFS:
retval = KRB5_RC_IO_PERM;
krb5_set_error_message (context, retval,
dgettext(TEXT_DOMAIN,
"Cannot open replay cache %s: %s"),
d->fn, strerror(errno));
break;
default:
retval = KRB5_RC_IO_UNKNOWN;
krb5_set_error_message (context, retval,
dgettext(TEXT_DOMAIN,
"Cannot open replay cache %s: %s"),
d->fn, strerror(errno));
}
}
/* Solaris: END made changes to be safer and better code structure */
if (retval) {
if (d->fn) {
if (!do_not_unlink)
(void) unlink(d->fn);
FREE_RC(d->fn);
d->fn = NULL;
}
if (d->fd >= 0)
(void) close(d->fd);
}
return retval;
}
krb5_error_code
krb5_rc_io_open(krb5_context context, krb5_rc_iostuff *d, char *fn)
{
return krb5_rc_io_open_internal(context, d, fn, NULL);
}
krb5_error_code
krb5_rc_io_move(krb5_context context, krb5_rc_iostuff *new1,
krb5_rc_iostuff *old)
{
#if defined(_WIN32) || defined(__CYGWIN__)
char *new_fn = NULL;
char *old_fn = NULL;
off_t offset = 0;
krb5_error_code retval = 0;
/*
* Initial work around provided by Tom Sanfilippo to work around
* poor Windows emulation of POSIX functions. Rename and dup has
* different semantics!
*
* Additional fixes and explanation provided by dalmeida@mit.edu:
*
* First, we save the offset of "old". Then, we close and remove
* the "new" file so we can do the rename. We also close "old" to
* make sure the rename succeeds (though that might not be
* necessary on some systems).
*
* Next, we do the rename. If all goes well, we seek the "new"
* file to the position "old" was at.
*
* --- WARNING!!! ---
*
* Since "old" is now gone, we mourn its disappearance, but we
* cannot emulate that Unix behavior... THIS BEHAVIOR IS
* DIFFERENT FROM UNIX. However, it is ok because this function
* gets called such that "old" gets closed right afterwards.
*/
offset = lseek(old->fd, 0, SEEK_CUR);
new_fn = new1->fn;
new1->fn = NULL;
close(new1->fd);
new1->fd = -1;
unlink(new_fn);
old_fn = old->fn;
old->fn = NULL;
close(old->fd);
old->fd = -1;
if (rename(old_fn, new_fn) == -1) { /* MUST be atomic! */
retval = KRB5_RC_IO_UNKNOWN;
goto cleanup;
}
retval = krb5_rc_io_open_internal(context, new1, 0, new_fn);
if (retval)
goto cleanup;
if (lseek(new1->fd, offset, SEEK_SET) == -1) {
retval = KRB5_RC_IO_UNKNOWN;
goto cleanup;
}
cleanup:
free(new_fn);
free(old_fn);
return retval;
#else
char *fn = NULL;
if (rename(old->fn, new1->fn) == -1) /* MUST be atomic! */
return KRB5_RC_IO_UNKNOWN;
fn = new1->fn;
new1->fn = NULL; /* avoid clobbering */
(void) krb5_rc_io_close(context, new1);
new1->fn = fn;
new1->fd = dup(old->fd);
return 0;
#endif
}
krb5_error_code
krb5_rc_io_write(krb5_context context, krb5_rc_iostuff *d, krb5_pointer buf,
unsigned int num)
{
if (write(d->fd, (char *) buf, num) == -1)
switch(errno)
{
#ifdef EDQUOT
case EDQUOT:
#endif
case EFBIG:
case ENOSPC:
krb5_set_error_message (context, KRB5_RC_IO_SPACE,
dgettext(TEXT_DOMAIN,
"Can't write to replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_SPACE;
case EIO:
krb5_set_error_message (context, KRB5_RC_IO_IO,
dgettext(TEXT_DOMAIN,
"Can't write to replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_IO;
case EBADF:
default:
krb5_set_error_message (context, KRB5_RC_IO_UNKNOWN,
dgettext(TEXT_DOMAIN,
"Can't write to replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_UNKNOWN;
}
return 0;
}
krb5_error_code
krb5_rc_io_sync(krb5_context context, krb5_rc_iostuff *d)
{
#if defined(_WIN32)
#ifndef fsync
#define fsync _commit
#endif
#endif
if (fsync(d->fd) == -1) {
switch(errno)
{
case EBADF: return KRB5_RC_IO_UNKNOWN;
case EIO: return KRB5_RC_IO_IO;
default:
krb5_set_error_message(context, KRB5_RC_IO_UNKNOWN,
dgettext(TEXT_DOMAIN,
"Cannot sync replay cache file %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_UNKNOWN;
}
}
return 0;
}
/*ARGSUSED*/
krb5_error_code
krb5_rc_io_read(krb5_context context, krb5_rc_iostuff *d, krb5_pointer buf,
unsigned int num)
{
int count;
if ((count = read(d->fd, (char *) buf, num)) == -1)
switch(errno)
{
case EIO: return KRB5_RC_IO_IO;
case EBADF:
default:
krb5_set_error_message(context, KRB5_RC_IO_UNKNOWN,
dgettext(TEXT_DOMAIN,
"Can't read from replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_UNKNOWN;
}
if (count == 0)
return KRB5_RC_IO_EOF;
return 0;
}
/*ARGSUSED*/
krb5_error_code
krb5_rc_io_close(krb5_context context, krb5_rc_iostuff *d)
{
if (d->fn != NULL) {
FREE_RC(d->fn);
d->fn = NULL;
}
if (d->fd != -1) {
if (close(d->fd) == -1) /* can't happen */
return KRB5_RC_IO_UNKNOWN;
d->fd = -1;
}
return 0;
}
/*ARGSUSED*/
krb5_error_code
krb5_rc_io_destroy(krb5_context context, krb5_rc_iostuff *d)
{
if (unlink(d->fn) == -1)
switch(errno)
{
case EIO:
krb5_set_error_message(context, KRB5_RC_IO_IO,
dgettext(TEXT_DOMAIN,
"Can't destroy replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_IO;
case EPERM:
case EBUSY:
case EROFS:
krb5_set_error_message(context, KRB5_RC_IO_PERM,
dgettext(TEXT_DOMAIN,
"Can't destroy replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_PERM;
case EBADF:
default:
krb5_set_error_message(context, KRB5_RC_IO_UNKNOWN,
dgettext(TEXT_DOMAIN,
"Can't destroy replay cache %s: %s"),
d->fn, strerror(errno));
return KRB5_RC_IO_UNKNOWN;
}
return 0;
}
/*ARGSUSED*/
krb5_error_code
krb5_rc_io_mark(krb5_context context, krb5_rc_iostuff *d)
{
d->mark = lseek(d->fd, (off_t) 0, SEEK_CUR); /* can't fail */
return 0;
}
/*ARGSUSED*/
krb5_error_code
krb5_rc_io_unmark(krb5_context context, krb5_rc_iostuff *d)
{
(void) lseek(d->fd, d->mark, SEEK_SET); /* if it fails, tough luck */
return 0;
}
/*ARGSUSED*/
long
krb5_rc_io_size(krb5_context context, krb5_rc_iostuff *d)
{
struct stat statb;
if (fstat(d->fd, &statb) == 0)
return statb.st_size;
else
return 0;
}