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#if efun(seteuid)
#include <module.h>
// string cvs_version = "$Id: privs.pike,v 1.35 1998/05/17 18:41:48 grubba Exp $";
int saved_uid;
int saved_gid;
int new_uid;
int new_gid;
#if !constant(report_notice)
#define report_notice werror
#define report_debug werror
#define report_warning werror
#endif
#define LOGP (roxen && roxen->variables && roxen->variables->audit && GLOBVAR(audit))
#define error(X) do{array Y=backtrace();throw(({(X),Y[..sizeof(Y)-2]}));}while(0)
#if constant(geteuid) && constant(getegid) && constant(seteuid) && constant(setegid)
#define HAVE_EFFECTIVE_USER
#endif
static private string _getcwd()
{
if (catch{return(getcwd());}) {
return("Unknown directory (no x-bit on current directory?)");
}
}
static private string dbt(array t)
{
if(!arrayp(t) || (sizeof(t)<2)) return "";
return (((t[0]||"Unknown program")-(_getcwd()+"/"))-"base_server/")+":"+t[1]+"\n";
}
#ifdef THREADS
mixed mutex_key; // Only one thread may modify the euid/egid at a time.
#endif /* THREADS */
int p_level;
void create(string reason, int|string|void uid, int|string|void gid)
{
#ifdef THREADS
#if constant(roxen_pid)
if(getpid() == roxen_pid)
werror("Using Privs ("+reason+") in threaded environment, source is\n "+
replace(describe_backtrace(backtrace()), "\n", "\n ")+"\n");
#endif
#endif
#ifdef HAVE_EFFECTIVE_USER
array u;
#ifdef THREADS
if (roxen->euid_egid_lock) {
catch { mutex_key = roxen->euid_egid_lock->lock(); };
}
#endif /* THREADS */
p_level = roxen->privs_level++;
if(getuid()) return;
/* Needs to be here since root-priviliges may be needed to
* use getpw{uid,nam}.
*/
saved_uid = geteuid();
saved_gid = getegid();
seteuid(0);
/* A string of digits? */
if (stringp(uid) && ((int)uid) &&
(replace(uid, ({ "0", "1", "2", "3", "4", "5", "6", "7", "8", "9" }),
({ "", "", "", "", "", "", "", "", "", "" })) == "")) {
uid = (int)uid;
}
if (stringp(gid) && ((int)gid) &&
(replace(gid, ({ "0", "1", "2", "3", "4", "5", "6", "7", "8", "9" }),
({ "", "", "", "", "", "", "", "", "", "" })) == "")) {
gid = (int)gid;
}
if(!stringp(uid)) {
u = getpwuid(uid);
} else {
u = getpwnam(uid);
if(u)
uid = u[2];
}
if(u && !gid) gid = u[3];
if(!u) {
if (uid && (uid != "root")) {
if (intp(uid) && (uid >= 60000)) {
report_debug(sprintf("privs.pike: User %d is not in the password database.\n"
"Assuming nobody.\n", uid));
// Nobody.
gid = gid || uid; // Fake a gid also.
u = ({ "fake-nobody", "x", uid, gid, "A real nobody", "/", "/sbin/sh" });
} else {
error("Unknown user: "+uid+"\n");
}
} else {
u = ({ "root", "x", 0, gid, "The super-user", "/", "/sbin/sh" });
}
}
if(LOGP)
report_notice(sprintf("Change to %s(%d):%d privs wanted (%s), from %s",
(string)u[0], (int)uid, (int)gid,
(string)reason,
(string)dbt(backtrace()[-2])));
#if efun(cleargroups)
catch { cleargroups(); };
#endif /* cleargroups */
#if efun(initgroups)
catch { initgroups(u[0], u[3]); };
#endif
gid = gid || getgid();
int err = (int)setegid(new_gid = gid);
if (err < 0) {
report_debug(sprintf("privs.pike: WARNING: Failed to set the effective group id to %d!\n"
"Check that your password database is correct for user %s(%d),\n"
"and that your group database is correct.\n",
gid, (string)u[0], (int)uid));
int gid2 = gid;
#ifdef HPUX_KLUDGE
if (gid >= 60000) {
/* HPUX has doesn't like groups higher than 60000,
* but has assigned nobody to group 60001 (which isn't even
* in /etc/group!).
*
* HPUX's libc also insists on filling numeric fields it doesn't like
* with the value 60001!
*/
perror("privs.pike: WARNING: Assuming nobody-group.\n"
"Trying some alternatives...\n");
// Assume we want the nobody group, and try a couple of alternatives
foreach(({ 60001, 65534, -2 }), gid2) {
perror("%d... ", gid2);
if (initgroups(u[0], gid2) >= 0) {
if ((err = setegid(new_gid = gid2)) >= 0) {
perror("Success!\n");
break;
}
}
}
}
#endif /* HPUX_KLUDGE */
if (err < 0) {
perror("privs.pike: Failed\n");
throw(({ sprintf("Failed to set EGID to %d\n", gid), backtrace() }));
}
perror("privs.pike: WARNING: Set egid to %d instead of %d.\n",
gid2, gid);
gid = gid2;
}
if(getgid()!=gid) setgid(gid||getgid());
seteuid(new_uid = uid);
#endif /* HAVE_EFFECTIVE_USER */
}
void destroy()
{
#ifdef HAVE_EFFECTIVE_USER
/* Check that we don't increase the privs level */
if (p_level >= roxen->privs_level) {
report_error(sprintf("Change back to uid#%d gid#%d from uid#%d gid#%d\n"
"in wrong order! Saved level:%d Current level:%d\n"
"Occurs in:\n%s\n",
saved_uid, saved_gid, new_uid, new_gid,
p_level, roxen->privs_level,
describe_backtrace(backtrace())));
return(0);
}
if (p_level != roxen->privs_level-1) {
report_error(sprintf("Change back to uid#%d gid#%d from uid#%d gid#%d\n"
"Skips privs level. Saved level:%d Current level:%d\n"
"Occurs in:\n%s\n",
saved_uid, saved_gid, new_uid, new_gid,
p_level, roxen->privs_level,
describe_backtrace(backtrace())));
}
roxen->privs_level = p_level;
if(LOGP) {
catch {
array bt = backtrace();
if (sizeof(bt) >= 2) {
report_notice(sprintf("Change back to uid#%d, from %s\n", saved_uid,
dbt(bt[-2])));
} else {
report_notice(sprintf("Change back to uid#%d, from backend\n",
saved_uid));
}
};
}
if(getuid()) return;
#ifdef DEBUG
int uid = geteuid();
if (uid != new_uid) {
report_warning(sprintf("Privs.pike: UID #%d differs from expected #%d\n"
"%s\n",
uid, new_uid, describe_backtrace(backtrace())));
}
int gid = getegid();
if (gid != new_gid) {
report_warning(sprintf("Privs.pike: GID #%d differs from expected #%d\n"
"%s\n",
gid, new_gid, describe_backtrace(backtrace())));
}
#endif /* DEBUG */
seteuid(0);
array u = getpwuid(saved_uid);
#if efun(cleargroups)
catch { cleargroups(); };
#endif /* cleargroups */
if(u && (sizeof(u) > 3)) {
catch { initgroups(u[0], u[3]); };
}
setegid(saved_gid);
seteuid(saved_uid);
#endif /* HAVE_EFFECTIVE_USER */
}
#endif
|
