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# The following is a security patch for rxvt, it (hopefully) avoids problems
# with unauthorized users obtaining root.
#
# Based upon code provided by Marc Ewing (marc@redhat.com) for a previous
# version of rxvt.
*** rxvt.h Sat Feb 19 09:41:52 1994
--- rxvt.h Wed Jan 10 23:42:09 1996
***************
*** 21,23 ****
--- 21,27 ----
extern void clean_exit(int);
extern void cleanutent(void);
extern void makeutent(char *);
+
+ void save_privs(void);
+ void get_privs(void);
+ void release_privs(void);
*** rxvt.c Fri Aug 5 08:52:07 1994
--- rxvt.c Wed Jan 10 23:45:04 1996
***************
*** 45,50 ****
--- 45,54 ----
int i;
char *shell;
char **com_argv;
+
+ /* Save and give up setuid/setgid privileges */
+ save_privs();
+ release_privs();
for (i = 0; i < argc; i++)
if (strcmp(argv[i],"-e") == 0)
*** command.c Thu Oct 20 07:35:44 1994
--- command.c Wed Jan 10 23:46:04 1996
***************
*** 222,227 ****
--- 222,247 ----
}
#endif
+ static uid_t saved_uid;
+ static gid_t saved_gid;
+
+ void save_privs()
+ {
+ saved_uid = geteuid();
+ saved_gid = getegid();
+ }
+
+ void get_privs()
+ {
+ seteuid(saved_uid);
+ seteuid(saved_gid);
+ }
+
+ void release_privs()
+ {
+ seteuid(getuid());
+ setegid(getgid());
+ }
/* Catch a SIGCHLD signal and exit if the direct child has died.
*/
***************
*** 337,344 ****
--- 357,366 ----
gid = gr->gr_gid;
else
gid = -1;
+ get_privs();
fchown(ttyfd,uid,gid);
fchmod(ttyfd,0600);
+ release_privs();
#endif
#ifdef TIOCCONS
if (console)
*** utmp.c Mon Oct 3 17:47:56 1994
--- utmp.c Wed Jan 10 23:48:56 1996
***************
*** 71,79 ****
--- 71,81 ----
extern char ttynam[];
extern struct stat ttyfd_stat;
+ get_privs();
chmod(ttynam,ttyfd_stat.st_mode);
chown(ttynam,ttyfd_stat.st_uid,ttyfd_stat.st_gid);
+ release_privs();
#endif
if(madeutent)
cleanutent();
***************
*** 166,171 ****
--- 168,174 ----
{
FILE *utmp;
+ get_privs();
if((utmp = fopen(UTMP,"r+")) == NULL)
return -1;
utmp_pos = get_tslot(ttyname) * sizeof(struct utmp);
***************
*** 174,179 ****
--- 177,183 ----
fseek(utmp,utmp_pos,0);
fwrite((char *)u, sizeof(struct utmp),1,utmp);
fclose(utmp);
+ release_privs();
madeutent = 1;
return(utmp_pos);
}
***************
*** 250,259 ****
--- 254,265 ----
int write_utmp(struct utmp * u)
{
int pos;
+ get_privs();
utmpname(UTMP);
setutent();
pututline(u);
endutent();
+ release_privs();
pos = (int)NULL;
madeutent = 1;
return(pos);
***************
*** 305,311 ****
{
int pid;
struct utmp *u;
!
utmpname(UTMP);
setutent();
pid = getpid();
--- 311,318 ----
{
int pid;
struct utmp *u;
!
! get_privs();
utmpname(UTMP);
setutent();
pid = getpid();
***************
*** 333,338 ****
--- 340,346 ----
endutent();
}
}
+ release_privs();
}
#endif /* BSD */
|
