一个使用des加密传输的unix下的login程序的服务器端和客户端.gz

/* * Copyright 1994 David A. Barrett. * * Remote login deaemon with authentication and data encryption of channel * * Revision History: * * 12-May-94: Fixed two malloc bugs in gendeskd.c and deslogind.c. * 14-Jun-94: * deslogind.c: Added -w option for login wrapper feature * -w option busted on HP-UX; wait for help. * Added RHOSTNAME environment variable. * utmp.c: added update of wtmp to writeut * log.c: ifdef'd return result from openlog * socket.c: errno.h inside #undef posix for ENOTSOCK (BSD/386) * tty.c: added control terminal setting for BSD/386 * changed "psignal" to "posignal" to avoid BSD name conflict * added changes for BSDI BSD/386 * changed include <ctype.h> before <stdlib.h> for BSD/386 * Thanks to Tom Markson <tom@twilight.com> for BSD/386 changes. * 24-Jan-95: Added WRITE_RETRY_TIME to txfr.c to fix linux lost connections * * Still to do: * Make the -w option work for HP-UX * Add '.' notation to hostname stuff on socket.c to allow IP addr to be used * figure out a way to run commands and pipelines: * it requires a way to make sure the pipes are flushed before exit * it may require detection of EOF across network * Add ip address to utmp entry for system V. fix in socket.c. * On hpux, can't reuse port numbers for a short while after exit. Why? * Check permissions on deslogin.users, and deslogin.log; issue warning. * Encrypt the log files too. * Catch all Coredump signals to prevent hostile user from signaling * us and examining the carcass for keys (deslogind, deslogingw). * How do you prevent a debugger from doing a ptrace(PT_ATTACH)? (cant!) * Compression (tricky because you must not impose delays) * Allow socket to be connected directly to resulting process * (won't happen because the parent is needed to encipher the data stream) * Figure out a way to improve protection from local users: * X11 server DISPLAY variable: * :0 still doesn't help because that creates a unix-domain socket: * named /usr/spool/sockets/X11/0 * * Deslogin: * Make sure that getPassphrase is not reading from unsecure device: * check $DISPLAY envt for 'local:' or ':' as prefix * check utmp to make sure not rlogin from somewhere else * permissions on Ctermid? Trojan Ctermid? * Protect against trojan of deslogin itself. * * Enhancements: * See rshd man page for internet socket login protocol. * Secondary socket for stderr ASCII port # '\0' terminated 0=none * upto 16 character server user name '\0' terminated * upto 16 character client user name '\0' terminated * command to execute limited by system's argument list * Server authenticates channel and sends a null byte to stderr sock * errors are sent with a '\1' as leading byte with mesage. * Notice that hpux rlogind man page describes a different protocol also. * Add passphrase command * * Inetd notes: * Umask and uid inherited from init and envt * Socket is available as stdin and stdout * * Notes: * I have set posignal so that SIGSTOP will not cause SIGCHLD. This allows * you to STOP a potential intruder in his tracks by sending SIGSTOP to * the process and then attach a debugger to it and examine what is going * on. * * Comments which Give a Section number and line number correspond to * quotes from IEEE Std 1003.1-1990 (ISO/IEC 9945-1: 1990). * (E.g. Sect5:10-12 means Section 5 lines 10 through 12 inclusive) */ #define _POSIX_SOURCE /* * This is a mess. HP-UX ANSI C won't define pid_t in <sys/types.h> unless * _POSIX_SOURCE is defined. Other machines may refuse to define it. Pick * what's appropriate. <utmp.h> uses pid_t. On __SOLARIS__, <utmpx.h> * uses (struct timeval) which won't be defined unless !_POSIX_SOURCE. */ #if defined(__SOLARIS__) /* { */ #undef _POSIX_SOURCE /* allows struct timeval to be defined */ #undef _POSIX_C_SOURCE #include <sys/types.h> /* gid_t pid_t uid_t clock_t */ #include <time.h> /* time (also needed for "utmp.h") */ #define _POSIX_SOURCE #define _POSIX_C_SOURCE #else /* } { */ #include <sys/types.h> /* gid_t pid_t uid_t clock_t */ #include <time.h> /* time (also needed for "utmp.h") */ #endif /* } */ #include <sys/times.h> /* struct tms */ /* mips fails to define prototype for times() unless */ /* __POSIX is defined. Strange. */ #include <unistd.h> /* chdir close dup execve fork */ /* getlogin getpid getppid getpgrp */ /* setsid setgid setpgid setuid ctermid */ /* _SC_NGROUPS_MAX */ #include <limits.h> /* NGROUPS_MAX */ #include <ctype.h> /* must be before stdlib.h for BSDI's BSD 386 */ #include <stdlib.h> /* atexit exit free malloc */ #include <stdio.h> /* (fopen fclose fgets scanf printf etc.) */ #include <string.h> /* memcmp memcpy memset */ #include <errno.h> #include <sys/stat.h> /* umask flags */ #include <fcntl.h> #include <termios.h> #include <signal.h> #include <pwd.h> #include <sys/wait.h> /* WNOHANG */ #include "pty.h" #include "tty.h" #include "auth.h" #include "txfr.h" #include "socket.h" #include "log.h" #include "deslogin.h" #include "posignal.h" #include "utmp.h" /* setlogin */ #include "group.h" /* getLoginGroups */ #if defined(sun) #define BSD #endif #if defined(mips) #define BSD #endif /* * Begin customizable area */ #if !defined(DEFAULT_UMASK) /* login user mask */ #define DEFAULT_UMASK S_IWGRP|S_IWOTH #endif #if !defined(TTY_MODE) /* login permissions for controlling terminal */ #define TTY_MODE (S_IRUSR|S_IWUSR|S_IWGRP|S_IWOTH) #endif #define TTY_RWANY (S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH) /* * These environment variables may be overwridden in the makefile */ #if defined(BSD) /* sun dec mips */ #if !defined(USERPATH) #define USERPATH ":/usr/ucb:/bin:/usr/bin" #endif #if !defined(SYSTEMPATH) #define SYSTEMPATH "/etc:/usr/ucb:/bin:/usr/bin" #endif #endif #if defined(hpux) /* hpux only */ #define DEFAULT_MAIL "/usr/mail/" #endif #if !defined(USER_ENV) /* Additional envt variable to store userName */ #define USER_ENV "USER" /* BSD (sun dec mips) xdm (not hpux) */ #endif #if !defined(USERPATH) #define USERPATH ":/bin:/usr/bin" #endif #if !defined(SYSTEMPATH) #define SYSTEMPATH "/etc:/bin:/usr/bin" #endif #if !defined(DEFAULT_TERM) #define DEFAULT_TERM "network" #endif #if !defined(USER_FILE) #define USER_FILE "/usr/local/etc/deslogind.users" #endif #if !defined(NOLOGIN_FILE) #define NOLOGIN_FILE "/etc/nologin" #endif #if !defined(LOG_FILE) #define LOG_FILE "/usr/adm/deslogind.log" #endif /* * End of customizable area */ #define PROGNAME_SIZE 255 #define USERNAME_SIZE 17 /* assumption based on rshd man page */ #define MAX_HOSTNAME 255 extern int optind; extern char *optarg; #if defined(__STDC__) || defined(__cplusplus) extern int askTty(char *, char *, unsigned, int); #else extern int askTty(); #endif extern unsigned long defaultKey[64]; static char ident[] = " @(#) deslogind.c version 1.32 03-Mar-95 Copyright 1995 by Dave Barrett(barrett@asgard.cs.Colorado.EDU)\n"; static char RCSid[] = " @(#) deslogind.c $Revision: 1.13 $ $Date: 95/03/08 01:13:14 $\n"; char mainProgName[PROGNAME_SIZE]; char *progName, *argcName; int debug = 0; int verbose = 0; unsigned long inBytes = 0; /* for txfr */ unsigned long outBytes = 0; struct termios oldmodes; char *defaultShell = "/bin/ksh"; char *defaultArgv[] = { (char *) 0, /* substituted with arg0 variable later */ (char *) 0, /* if -w, then substitudet with loginArg1 */ (char *) 0, /* if -w, then remote host name */ (char *) 0 }; /* * Static data for -w option */ char loginArg1[] = "-h"; char loginProg[] = LOGIN_PROG; char loginCwd[] = "/"; void setProgName() { pid_t pid = getpid(); /* can't fail */ sprintf(mainProgName, "%s[%lu]", ar