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Diff for /src/usr.bin/ssh/uidswap.c between version 1.9.2.3 and 1.9.2.4

version 1.9.2.3, 2001/03/21 19:46:32 version 1.9.2.4, 2001/05/07 21:09:39
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  * POSIX saved uids or not.   * POSIX saved uids or not.
  */   */
   
 #ifdef _POSIX_SAVED_IDS  
 /* Lets assume that posix saved ids also work with seteuid, even though that  /* Lets assume that posix saved ids also work with seteuid, even though that
    is not part of the posix specification. */     is not part of the posix specification. */
 #define SAVED_IDS_WORK_WITH_SETEUID  
 /* Saved effective uid. */  /* Saved effective uid. */
 static uid_t saved_euid = 0;  static int      privileged = 0;
 #endif /* _POSIX_SAVED_IDS */  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;
   
 /*  /*
  * Temporarily changes to the given uid.  If the effective user   * Temporarily changes to the given uid.  If the effective user
  * id is not root, this does nothing.  This call cannot be nested.   * id is not root, this does nothing.  This call cannot be nested.
  */   */
 void  void
 temporarily_use_uid(uid_t uid)  temporarily_use_uid(struct passwd *pw)
 {  {
 #ifdef SAVED_IDS_WORK_WITH_SETEUID          /* Save the current euid, and egroups. */
         /* Save the current euid. */  
         saved_euid = geteuid();          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. */          /* Set the effective uid to the given (unprivileged) uid. */
         if (seteuid(uid) == -1)          if (setgroups(user_groupslen, user_groups) < 0)
                 debug("seteuid %u: %.100s", (u_int) uid, strerror(errno));                  fatal("setgroups: %.100s", strerror(errno));
 #else /* SAVED_IDS_WORK_WITH_SETEUID */          pw->pw_gid = pw->pw_gid;
         /* Propagate the privileged uid to all of our uids. */          if (setegid(pw->pw_gid) < 0)
         if (setuid(geteuid()) < 0)                  fatal("setegid %u: %.100s", (u_int) pw->pw_gid,
                 debug("setuid %u: %.100s", (u_int) geteuid(), strerror(errno));                      strerror(errno));
           if (seteuid(pw->pw_uid) == -1)
         /* Set the effective uid to the given (unprivileged) uid. */                  fatal("seteuid %u: %.100s", (u_int) pw->pw_uid,
         if (seteuid(uid) == -1)                      strerror(errno));
                 debug("seteuid %u: %.100s", (u_int) uid, strerror(errno));  
 #endif /* SAVED_IDS_WORK_WITH_SETEUID */  
 }  }
   
 /*  /*
  * Restores to the original uid.   * Restores to the original (privileged) uid.
  */   */
 void  void
 restore_uid(void)  restore_uid(void)
 {  {
 #ifdef SAVED_IDS_WORK_WITH_SETEUID          debug("restore_uid");
         /* Set the effective uid back to the saved 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. */
         if (seteuid(saved_euid) < 0)          if (seteuid(saved_euid) < 0)
                 debug("seteuid %u: %.100s", (u_int) saved_euid, strerror(errno));                  fatal("seteuid %u: %.100s", (u_int) saved_euid, strerror(errno));
 #else /* SAVED_IDS_WORK_WITH_SETEUID */          if (setgroups(saved_egroupslen, saved_egroups) < 0)
         /*                  fatal("setgroups: %.100s", strerror(errno));
          * We are unable to restore the real uid to its unprivileged value.          if (setegid(saved_egid) < 0)
          * Propagate the real uid (usually more privileged) to effective uid                  fatal("setegid %u: %.100s", (u_int) saved_egid, strerror(errno));
          * as well.          temporarily_use_uid_effective = 0;
          */  
         setuid(getuid());  
 #endif /* SAVED_IDS_WORK_WITH_SETEUID */  
 }  }
   
 /*  /*
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  * called while temporarily_use_uid is effective.   * called while temporarily_use_uid is effective.
  */   */
 void  void
 permanently_set_uid(uid_t uid)  permanently_set_uid(struct passwd *pw)
 {  {
         if (setuid(uid) < 0)          if (temporarily_use_uid_effective)
                 debug("setuid %u: %.100s", (u_int) uid, strerror(errno));                  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));
 }  }
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Removed from v.1.9.2.3  
changed lines
  Added in v.1.9.2.4