===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/uidswap.c,v
retrieving revision 1.9.2.6
retrieving revision 1.10
diff -u -r1.9.2.6 -r1.10
--- src/usr.bin/ssh/uidswap.c	2002/03/08 17:04:44	1.9.2.6
+++ src/usr.bin/ssh/uidswap.c	2000/12/17 09:33:40	1.10
@@ -12,9 +12,9 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: uidswap.c,v 1.9.2.6 2002/03/08 17:04:44 brad Exp $");
+RCSID("$OpenBSD: uidswap.c,v 1.10 2000/12/17 09:33:40 markus Exp $");
 
-#include "log.h"
+#include "ssh.h"
 #include "uidswap.h"
 
 /*
@@ -26,80 +26,58 @@
  * POSIX saved uids or not.
  */
 
+#ifdef _POSIX_SAVED_IDS
 /* Lets assume that posix saved ids also work with seteuid, even though that
    is not part of the posix specification. */
+#define SAVED_IDS_WORK_WITH_SETEUID
+#endif /* _POSIX_SAVED_IDS */
 
 /* Saved effective uid. */
-static int	privileged = 0;
-static int	temporarily_use_uid_effective = 0;
-static uid_t	saved_euid = 0;
-static gid_t	saved_egid;
-static gid_t	saved_egroups[NGROUPS_MAX], user_groups[NGROUPS_MAX];
-static int	saved_egroupslen = -1, user_groupslen = -1;
+static uid_t saved_euid = 0;
 
 /*
  * Temporarily changes to the given uid.  If the effective user
  * id is not root, this does nothing.  This call cannot be nested.
  */
 void
-temporarily_use_uid(struct passwd *pw)
+temporarily_use_uid(uid_t uid)
 {
-	/* Save the current euid, and egroups. */
+#ifdef SAVED_IDS_WORK_WITH_SETEUID
+	/* Save the current euid. */
 	saved_euid = geteuid();
-	debug("temporarily_use_uid: %d/%d (e=%d)",
-	    pw->pw_uid, pw->pw_gid, saved_euid);
-	if (saved_euid != 0) {
-		privileged = 0;
-		return;
-	}
-	privileged = 1;
-	temporarily_use_uid_effective = 1;
-	saved_egid = getegid();
-	saved_egroupslen = getgroups(NGROUPS_MAX, saved_egroups);
-	if (saved_egroupslen < 0)
-		fatal("getgroups: %.100s", strerror(errno));
 
-	/* set and save the user's groups */
-	if (user_groupslen == -1) {
-		if (initgroups(pw->pw_name, pw->pw_gid) < 0)
-			fatal("initgroups: %s: %.100s", pw->pw_name,
-			    strerror(errno));
-		user_groupslen = getgroups(NGROUPS_MAX, user_groups);
-		if (user_groupslen < 0)
-			fatal("getgroups: %.100s", strerror(errno));
-	}
 	/* Set the effective uid to the given (unprivileged) uid. */
-	if (setgroups(user_groupslen, user_groups) < 0)
-		fatal("setgroups: %.100s", strerror(errno));
-	pw->pw_gid = pw->pw_gid;
-	if (setegid(pw->pw_gid) < 0)
-		fatal("setegid %u: %.100s", (u_int) pw->pw_gid,
-		    strerror(errno));
-	if (seteuid(pw->pw_uid) == -1)
-		fatal("seteuid %u: %.100s", (u_int) pw->pw_uid,
-		    strerror(errno));
+	if (seteuid(uid) == -1)
+		debug("seteuid %u: %.100s", (u_int) uid, strerror(errno));
+#else /* SAVED_IDS_WORK_WITH_SETEUID */
+	/* Propagate the privileged uid to all of our uids. */
+	if (setuid(geteuid()) < 0)
+		debug("setuid %u: %.100s", (u_int) geteuid(), strerror(errno));
+
+	/* Set the effective uid to the given (unprivileged) uid. */
+	if (seteuid(uid) == -1)
+		debug("seteuid %u: %.100s", (u_int) uid, strerror(errno));
+#endif /* SAVED_IDS_WORK_WITH_SETEUID */
 }
 
 /*
- * Restores to the original (privileged) uid.
+ * Restores to the original uid.
  */
 void
-restore_uid(void)
+restore_uid()
 {
-	debug("restore_uid");
-	/* it's a no-op unless privileged */
-	if (!privileged)
-		return;
-	if (!temporarily_use_uid_effective)
-		fatal("restore_uid: temporarily_use_uid not effective");
-	/* Set the effective uid back to the saved privileged uid. */
+#ifdef SAVED_IDS_WORK_WITH_SETEUID
+	/* Set the effective uid back to the saved uid. */
 	if (seteuid(saved_euid) < 0)
-		fatal("seteuid %u: %.100s", (u_int) saved_euid, strerror(errno));
-	if (setgroups(saved_egroupslen, saved_egroups) < 0)
-		fatal("setgroups: %.100s", strerror(errno));
-	if (setegid(saved_egid) < 0)
-		fatal("setegid %u: %.100s", (u_int) saved_egid, strerror(errno));
-	temporarily_use_uid_effective = 0;
+		debug("seteuid %u: %.100s", (u_int) saved_euid, strerror(errno));
+#else /* SAVED_IDS_WORK_WITH_SETEUID */
+	/*
+	 * We are unable to restore the real uid to its unprivileged value.
+	 * Propagate the real uid (usually more privileged) to effective uid
+	 * as well.
+	 */
+	setuid(getuid());
+#endif /* SAVED_IDS_WORK_WITH_SETEUID */
 }
 
 /*
@@ -107,12 +85,8 @@
  * called while temporarily_use_uid is effective.
  */
 void
-permanently_set_uid(struct passwd *pw)
+permanently_set_uid(uid_t uid)
 {
-	if (temporarily_use_uid_effective)
-		fatal("restore_uid: temporarily_use_uid effective");
-	if (setgid(pw->pw_gid) < 0)
-		fatal("setgid %u: %.100s", (u_int) pw->pw_gid, strerror(errno));
-	if (setuid(pw->pw_uid) < 0)
-		fatal("setuid %u: %.100s", (u_int) pw->pw_uid, strerror(errno));
+	if (setuid(uid) < 0)
+		debug("setuid %u: %.100s", (u_int) uid, strerror(errno));
 }