+#ifndef lint
+static char sccsid[] = "@(#)rshd.c 4.1 82/04/02";
+#endif
+
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <net/in.h>
+#include <errno.h>
+#include <pwd.h>
+#include <wait.h>
+#include <signal.h>
+
+int errno;
+struct sockaddr_in sin = { AF_INET, IPPORT_CMDSERVER };
+struct passwd *getpwnam();
+char *index(), *rindex(), *raddr(), *sprintf();
+int options = SO_ACCEPTCONN|SO_KEEPALIVE;
+/* VARARGS 1 */
+int error();
+/*
+ * remote execute server:
+ * remuser\0
+ * locuser\0
+ * command\0
+ * data
+ */
+main(argc, argv)
+ int argc;
+ char **argv;
+{
+ union wait status;
+ int f;
+ struct sockaddr_in from;
+
+#ifndef DEBUG
+ if (fork())
+ exit(0);
+ for (f = 0; f < 10; f++)
+ (void) close(f);
+ (void) open("/", 0);
+ (void) dup2(0, 1);
+ (void) dup2(0, 2);
+ { int t = open("/dev/tty", 2);
+ if (t >= 0) {
+ ioctl(t, TIOCNOTTY, (char *)0);
+ (void) close(t);
+ }
+ }
+#endif
+#if vax
+ sin.sin_port = htons(sin.sin_port);
+#endif
+ argc--, argv++;
+ if (argc > 0 && !strcmp(argv[0], "-d"))
+ options |= SO_DEBUG;
+ for (;;) {
+ errno = 0;
+ f = socket(SOCK_STREAM, 0, &sin, options);
+ if (f < 0) {
+ perror("socket");
+ sleep(5);
+ continue;
+ }
+ if (accept(f, &from) < 0) {
+ perror("accept");
+ (void) close(f);
+ sleep(1);
+ continue;
+ }
+ if (fork() == 0)
+ doit(f, &from);
+ (void) close(f);
+ while(wait3(status, WNOHANG, 0) > 0)
+ continue;
+ }
+}
+
+char username[20] = "USER=";
+char homedir[64] = "HOME=";
+char shell[64] = "SHELL=";
+char *envinit[] =
+ {homedir, shell, "PATH=:/usr/ucb:/bin:/usr/bin", username, 0};
+char **environ;
+
+doit(f, fromp)
+ int f;
+ struct sockaddr_in *fromp;
+{
+ char cmdbuf[NCARGS+1], *cp;
+ char locuser[16], remuser[16];
+ struct passwd *pwd;
+ char *rhost;
+ int s;
+ short port;
+ int pv[2], pid, ready, readfrom, cc;
+ char buf[BUFSIZ], sig;
+ int one = 1;
+
+ (void) signal(SIGINT, SIG_DFL);
+ (void) signal(SIGQUIT, SIG_DFL);
+ (void) signal(SIGTERM, SIG_DFL);
+#ifdef DEBUG
+ { int t = open("/dev/tty", 2);
+ if (t >= 0) {
+ ioctl(t, TIOCNOTTY, (char *)0);
+ (void) close(t);
+ }
+ }
+#endif
+ dup2(f, 0);
+ dup2(f, 1);
+ dup2(f, 2);
+#if vax
+ fromp->sin_port = ntohs((u_short)fromp->sin_port);
+#endif
+ if (fromp->sin_family != AF_INET ||
+ fromp->sin_port >= IPPORT_RESERVED)
+ exit(1);
+ (void) alarm(60);
+ port = 0;
+ for (;;) {
+ char c;
+ if (read(f, &c, 1) != 1)
+ exit(1);
+ if (c == 0)
+ break;
+ port = port * 10 + c - '0';
+ }
+ (void) alarm(0);
+ if (port != 0) {
+ s = rresvport(0);
+ if (s < 0)
+ exit(1);
+ if (port >= IPPORT_RESERVED)
+ goto protofail;
+ (void) alarm(60);
+ fromp->sin_port = port;
+#if vax
+ fromp->sin_port = ntohs(fromp->sin_port);
+#endif
+ if (connect(s, fromp) < 0)
+ exit(1);
+ (void) alarm(0);
+ }
+ rhost = raddr(fromp->sin_addr.s_addr);
+ if (rhost == 0) {
+ error("Host name for your address unknown\n");
+ exit(1);
+ }
+ getstr(remuser, sizeof(remuser), "remuser");
+ getstr(locuser, sizeof(locuser), "locuser");
+ getstr(cmdbuf, sizeof(cmdbuf), "command");
+ setpwent();
+ pwd = getpwnam(locuser);
+ if (pwd == NULL) {
+ error("Login incorrect.\n");
+ exit(1);
+ }
+ endpwent();
+ if (chdir(pwd->pw_dir) < 0) {
+ error("No remote directory.\n");
+ exit(1);
+ }
+ if (ruserok(rhost, remuser, locuser) < 0) {
+ error("Permission denied.\n");
+ exit(1);
+ }
+ (void) write(2, "\0", 1);
+ if (port) {
+ if (pipe(pv) < 0) {
+ error("Can't make pipe.\n");
+ exit(1);
+ }
+ pid = fork();
+ if (pid == -1) {
+ error("Try again.\n");
+ exit(1);
+ }
+ if (pid) {
+ (void) close(0); (void) close(1); (void) close(2);
+ (void) close(f); (void) close(pv[1]);
+ readfrom = (1<<s) | (1<<pv[0]);
+ ioctl(pv[1], FIONBIO, (char *)&one);
+ /* should set s nbio! */
+ do {
+ ready = readfrom;
+ (void) select(32, &ready, 0, 1000000);
+ if (ready & (1<<s)) {
+ if (read(s, &sig, 1) <= 0)
+ readfrom &= ~(1<<s);
+ else
+ killpg(pid, sig);
+ }
+ if (ready & (1<<pv[0])) {
+ cc = read(pv[0], buf, sizeof (buf));
+ if (cc <= 0) {
+ int done = 1+1;
+ ioctl(s, SIOCDONE, (char *)&done);
+ readfrom &= ~(1<<pv[0]);
+ } else
+ (void) write(s, buf, cc);
+ }
+ } while (readfrom);
+ exit(0);
+ }
+ setpgrp(0, getpid());
+ (void) close(s); (void) close(pv[0]);
+ dup2(pv[1], 2);
+ }
+ if (*pwd->pw_shell == '\0')
+ pwd->pw_shell = "/bin/sh";
+ (void) close(f);
+ inigrp(pwd->pw_name, pwd->pw_gid);
+ (void) setuid(pwd->pw_uid);
+ (void) setgid(pwd->pw_gid);
+ environ = envinit;
+ strncat(homedir, pwd->pw_dir, sizeof(homedir)-6);
+ strncat(shell, pwd->pw_shell, sizeof(shell)-7);
+ strncat(username, pwd->pw_name, sizeof(username)-6);
+ cp = rindex(pwd->pw_shell, '/');
+ if (cp)
+ cp++;
+ else
+ cp = pwd->pw_shell;
+ execl(pwd->pw_shell, cp, "-c", cmdbuf, 0);
+ perror(pwd->pw_shell);
+ exit(1);
+protofail:
+ error("rsh: protocol failure detected by remote\n");
+ exit(1);
+}
+
+/* VARARGS 1 */
+error(fmt)
+ char *fmt;
+{
+ char buf[BUFSIZ];
+
+ buf[0] = 1;
+ (void) sprintf(buf+1, fmt);
+ (void) write(2, buf, strlen(buf));
+}
+
+getstr(buf, cnt, err)
+ char *buf;
+ int cnt;
+ char *err;
+{
+ char c;
+
+ do {
+ if (read(0, &c, 1) != 1)
+ exit(1);
+ *buf++ = c;
+ if (--cnt == 0) {
+ error("%s too long\n", err);
+ exit(1);
+ }
+ } while (c != 0);
+}
projects / unix-history / commitdiff