--- rxvt-unicode/src/ptytty.C 2006/01/23 12:37:59 1.60 +++ rxvt-unicode/src/ptytty.C 2006/01/25 10:51:26 1.61 @@ -34,7 +34,6 @@ #include #include -#include #include #include @@ -374,343 +373,3 @@ return true; } -///////////////////////////////////////////////////////////////////////////// -// helper/proxy support - -#if PTYTTY_HELPER - -static int sock_fd = -1, lock_fd = -1; -static int helper_pid, owner_pid; - -struct command -{ - enum { get, login, destroy } type; - - ptytty *id; - - bool login_shell; - int cmd_pid; - char hostname[512]; // arbitrary, but should be plenty -}; - -struct ptytty_proxy : ptytty -{ - ptytty *id; - - ptytty_proxy () - : id(0) - { - } - - ~ptytty_proxy (); - - bool get (); - void login (int cmd_pid, bool login_shell, const char *hostname); -}; - -#if PTYTTY_REENTRANT -# define NEED_TOKEN do { char ch; read (lock_fd, &ch, 1); } while (0) -# define GIVE_TOKEN do { char ch; write (lock_fd, &ch, 1); } while (0) -#else -# define NEED_TOKEN (void)0 -# define GIVE_TOKEN (void)0 -#endif - -bool -ptytty_proxy::get () -{ - NEED_TOKEN; - - command cmd; - - cmd.type = command::get; - - write (sock_fd, &cmd, sizeof (cmd)); - - if (read (sock_fd, &id, sizeof (id)) != sizeof (id)) - ptytty_fatal ("protocol error while creating pty using helper process, aborting.\n"); - - if (!id) - { - GIVE_TOKEN; - return false; - } - - if ((pty = recv_fd (sock_fd)) < 0 - || (tty = recv_fd (sock_fd)) < 0) - ptytty_fatal ("protocol error while reading pty/tty fds from helper process, aborting.\n"); - - GIVE_TOKEN; - return true; -} - -void -ptytty_proxy::login (int cmd_pid, bool login_shell, const char *hostname) -{ - NEED_TOKEN; - - command cmd; - - cmd.type = command::login; - cmd.id = id; - cmd.cmd_pid = cmd_pid; - cmd.login_shell = login_shell; - strncpy (cmd.hostname, hostname, sizeof (cmd.hostname)); - - write (sock_fd, &cmd, sizeof (cmd)); - - GIVE_TOKEN; -} - -ptytty_proxy::~ptytty_proxy () -{ - if (id) - { - NEED_TOKEN; - - command cmd; - - cmd.type = command::destroy; - cmd.id = id; - - write (sock_fd, &cmd, sizeof (cmd)); - - GIVE_TOKEN; - } -} - -static -void serve () -{ - command cmd; - vector ptys; - - for (;;) - { - GIVE_TOKEN; - - if (read (sock_fd, &cmd, sizeof (command)) != sizeof (command)) - break; - - if (cmd.type == command::get) - { - // -> id ptyfd ttyfd - cmd.id = new ptytty_unix; - - if (cmd.id->get ()) - { - write (sock_fd, &cmd.id, sizeof (cmd.id)); - ptys.push_back (cmd.id); - - ptytty::send_fd (sock_fd, cmd.id->pty); - ptytty::send_fd (sock_fd, cmd.id->tty); - } - else - { - delete cmd.id; - cmd.id = 0; - write (sock_fd, &cmd.id, sizeof (cmd.id)); - } - } - else if (cmd.type == command::login) - { -#if UTMP_SUPPORT - if (find (ptys.begin (), ptys.end (), cmd.id) != ptys.end ()) - { - cmd.hostname[sizeof (cmd.hostname) - 1] = 0; - cmd.id->login (cmd.cmd_pid, cmd.login_shell, cmd.hostname); - } -#endif - } - else if (cmd.type == command::destroy) - { - vector::iterator pty = find (ptys.begin (), ptys.end (), cmd.id); - - if (pty != ptys.end ()) - { - delete *pty; - ptys.erase (pty); - } - } - else - break; - - NEED_TOKEN; - } - - // destroy all ptys - for (vector::iterator i = ptys.end (); i-- > ptys.begin (); ) - delete *i; -} - -void -ptytty::use_helper () -{ -#ifndef PTYTTY_NO_PID_CHECK - int pid = getpid (); -#endif - - if (sock_fd >= 0 -#ifndef PTYTTY_NO_PID_CHECK - && pid == owner_pid -#endif - ) - return; - -#ifndef PTYTTY_NO_PID_CHECK - owner_pid = pid; -#endif - - int sv[2]; - - if (socketpair (AF_UNIX, SOCK_STREAM, 0, sv)) - ptytty_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n"); - -#ifdef PTYTTY_REENTRANT - int lv[2]; - - if (socketpair (AF_UNIX, SOCK_STREAM, 0, lv)) - ptytty_fatal ("could not create socket to communicate with pty/sessiondb helper, aborting.\n"); -#endif - - helper_pid = fork (); - - if (helper_pid < 0) - ptytty_fatal ("could not create pty/sessiondb helper process, aborting.\n"); - - if (helper_pid) - { - // client, process - sock_fd = sv[0]; - close (sv[1]); - fcntl (sock_fd, F_SETFD, FD_CLOEXEC); -#ifdef PTYTTY_REENTRANT - lock_fd = lv[0]; - close (lv[1]); - fcntl (lock_fd, F_SETFD, FD_CLOEXEC); -#endif - } - else - { - // server, pty-helper - sock_fd = sv[1]; -#ifdef PTYTTY_REENTRANT - lock_fd = lv[1]; -#endif - - chdir ("/"); - - signal (SIGHUP, SIG_IGN); - signal (SIGTERM, SIG_IGN); - signal (SIGINT, SIG_IGN); - signal (SIGPIPE, SIG_IGN); - - for (int fd = 0; fd < 1023; fd++) - if (fd != sock_fd && fd != lock_fd) - close (fd); - - serve (); - _exit (EXIT_SUCCESS); - } -} - -#endif - -ptytty * -ptytty::create () -{ -#if PTYTTY_HELPER - if (helper_pid -# ifndef PTYTTY_NO_PID_CHECK - && getpid () == owner_pid -# endif - ) - // use helper process - return new ptytty_proxy; - else -#endif - return new ptytty_unix; -} - -void -ptytty::init () -{ - uid_t uid = getuid (); - gid_t gid = getgid (); - - // before doing anything else, check for setuid/setgid operation, - // start the helper process and drop privileges - if (uid != geteuid () - || gid != getegid ()) - { -#if PTYTTY_HELPER - use_helper (); -#else - ptytty_warn ("running setuid/setgid without pty helper compiled in, continuing unprivileged.\n"); -#endif - - drop_privileges (); - } -} - -void -ptytty::drop_privileges () -{ - uid_t uid = getuid (); - gid_t gid = getgid (); - - // drop privileges -#if HAVE_SETRESUID - setresgid (gid, gid, gid); - setresuid (uid, uid, uid); -#elif HAVE_SETREUID - setregid (gid, gid); - setreuid (uid, uid); -#elif HAVE_SETUID - setgid (gid); - setuid (uid); -#endif - - if (uid != geteuid () - || gid != getegid ()) - ptytty_fatal ("unable to drop privileges, aborting.\n"); -} - -///////////////////////////////////////////////////////////////////////////// -// C API - -#ifndef PTYTTY_NO_C_API - -typedef void *PTYTTY; - -#define DEFINE_METHOD(retval, name, args1, args2) \ -extern "C" retval ptytty_ ## name args1 \ -{ return ((struct ptytty *)ptytty)->name args2; } - -DEFINE_METHOD(int,pty,(PTYTTY ptytty),) -DEFINE_METHOD(int,tty,(PTYTTY ptytty),) -DEFINE_METHOD(int,get,(PTYTTY ptytty),()) -DEFINE_METHOD(void,login,(PTYTTY ptytty, int cmd_pid, bool login_shell, const char *hostname),(cmd_pid,login_shell,hostname)) - -DEFINE_METHOD(void,close_tty,(PTYTTY ptytty),()) -DEFINE_METHOD(int,make_controlling_tty,(PTYTTY ptytty),()) -DEFINE_METHOD(void,set_utf8_mode,(PTYTTY ptytty, int on),(on)) - -#define DEFINE_STATIC(retval, name, args) \ -extern "C" retval ptytty_ ## name args \ -{ return ptytty::name args; } - -DEFINE_STATIC(void,drop_privileges,()) -DEFINE_STATIC(void,use_helper,()) -DEFINE_STATIC(void,init,()) - -DEFINE_STATIC(PTYTTY ,create,()) - -void ptytty_delete (PTYTTY ptytty) -{ - delete (struct ptytty *)ptytty; -} - -// send_fd, recv_fd not exposed - -#endif