static char sccsid[] = "@(#)nsh.c 4.2 (Berkeley) 10/02/82"; # include "defs.h" /* nsh -c "comand to be executed" This pseudo-shell is executed over the network as the login shell of an acount "network", no passwd. It will only execute certain allowed commands. has these exit codes: EX_USAGE = wrong # arguments to nsh 9 = command you execute may not take arguments 10= the execl failed EX_UNAVAILABLE= could not find full path name for the command count is the # of arguments (= argc) allowed. a count of 0 turns off the command */ struct { char *app; char count; char *full; char *full1; } st[] = { /* I assume these are the same for RAND */ "mmail", 20, "/usr/net/bin/mmail", "/usr/net/bin/mmail", "mwrite", 20, "/usr/net/bin/mwrite", "/usr/net/bin/mwrite", "prmail", 20, "/usr/net/bin/prmail", "/usr/net/bin/prmail", # ifndef NFREECMD "bpq", 20, "/usr/bin/bpq", "/bin/bpq", "epq", 20, "/usr/bin/epq", "/bin/epq", "finger", 20, "/usr/ucb/finger", "/usr/bin/finger", "help", 20, "/bin/help", "/usr/bin/help", "lpq", 20, "/usr/bin/lpq", "/bin/lpq", # ifdef FREELPR "lpr", 20, "/usr/bin/lpr", "/bin/lpr", # endif "netlog", 20, "/usr/bin/netlog", "/usr/ucb/netlog", "netq", 20, "/usr/bin/netq", "/usr/ucb/netq", "news", 20, "/usr/bin/news", "/usr/ucb/news", "ps", 20, "/bin/ps", "/usr/bin/ps", "pstat", 20, "/usr/bin/pstat", "/bin/pstat", "rcs", 20, "/usr/bin/rcs", "/bin/rcs", "rcslog", 1, "/usr/bin/rcslog", "/bin/rcslog", "rcsq", 20, "/usr/bin/rcsq", "/bin/rcsq", "trq", 20, "/usr/bin/trq", "/bin/trq", "vpq", 20, "/usr/ucb/vpq", "/usr/bin/vpq", "w", 20, "/usr/ucb/w", "/usr/bin/w", "wc", 20, "/usr/bin/wc", "/bin/wc", "where", 20, "/usr/bin/where", "/bin/where", "who", 20, "/bin/who", "/usr/bin/who", "whom", 20, "/usr/ucb/whom", "/usr/bin/whom", "write", 20, "/usr/bin/write", "/bin/write", "yank", 20, "/usr/ucb/yank", "/usr/bin/yank", # endif 0, 0, 0, 0 }; /* nsh -c cmd */ main(argc,argv) char **argv; { char *s, buf[500]; int i, flg = 0; if(argc != 3){ fprintf(stderr,"Wrong number of arguments to nsh.\n"); exit(EX_USAGE); } s = argv[2]; while(*s && *s != ' ')s++; if(*s == ' ')flg++; *s = 0; if((i = mlookup(argv[2])) < 0){ fprintf(stderr, "Command '%s' is not allowed if logged in as 'network'.\n", argv[2]); exit(11); } if(st[i].count == 0){ fprintf(stderr, "The command '%s' is not allowed to have arguments.\n",argv[2]); exit(9); } if(stat(st[i].full,buf) >= 0) strcpy(buf,st[i].full); else strcpy(buf,st[i].full1); if(flg && st[i].count > 1){ /* some cmds don't allow parms */ *s = ' '; strcat(buf,s); } /* fprintf(stderr,"%s\n",buf); */ execl(Bsh,"sh","-c",buf,0); fprintf(stderr,"Execute of shell failed.\n"); exit(EX_UNAVAILABLE); } mlookup(s) char *s; { int i; for(i = 0; st[i].app; i++) if(strcmp(st[i].app,s) == 0 || strcmp(st[i].full,s) == 0 || strcmp(st[i].full1,s) == 0)return(i); return(-1); }