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-rw-r--r--inet/rcmd.c414
1 files changed, 414 insertions, 0 deletions
diff --git a/inet/rcmd.c b/inet/rcmd.c
new file mode 100644
index 0000000000..e5b28c63f8
--- /dev/null
+++ b/inet/rcmd.c
@@ -0,0 +1,414 @@
+/*
+ * Copyright (c) 1983, 1993, 1994
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)rcmd.c	8.3 (Berkeley) 3/26/94";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <signal.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <pwd.h>
+#include <errno.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+
+int	__ivaliduser __P((FILE *, u_long, const char *, const char *));
+static int __icheckhost __P((u_long, char *));
+
+int
+rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
+	char **ahost;
+	u_short rport;
+	const char *locuser, *remuser, *cmd;
+	int *fd2p;
+{
+	struct hostent *hp;
+	struct sockaddr_in sin, from;
+	fd_set reads;
+	long oldmask;
+	pid_t pid;
+	int s, lport, timo;
+	char c;
+
+	pid = getpid();
+	hp = gethostbyname(*ahost);
+	if (hp == NULL) {
+		herror(*ahost);
+		return (-1);
+	}
+	*ahost = hp->h_name;
+	oldmask = sigblock(sigmask(SIGURG));
+	for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
+		s = rresvport(&lport);
+		if (s < 0) {
+			if (errno == EAGAIN)
+				(void)fprintf(stderr,
+				    "rcmd: socket: All ports in use\n");
+			else
+				(void)fprintf(stderr, "rcmd: socket: %s\n",
+				    strerror(errno));
+			sigsetmask(oldmask);
+			return (-1);
+		}
+		fcntl(s, F_SETOWN, pid);
+		sin.sin_family = hp->h_addrtype;
+		bcopy(hp->h_addr_list[0], &sin.sin_addr, hp->h_length);
+		sin.sin_port = rport;
+		if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
+			break;
+		(void)close(s);
+		if (errno == EADDRINUSE) {
+			lport--;
+			continue;
+		}
+		if (errno == ECONNREFUSED && timo <= 16) {
+			(void)sleep(timo);
+			timo *= 2;
+			continue;
+		}
+		if (hp->h_addr_list[1] != NULL) {
+			int oerrno = errno;
+
+			(void)fprintf(stderr, "connect to address %s: ",
+			    inet_ntoa(sin.sin_addr));
+			errno = oerrno;
+			perror(0);
+			hp->h_addr_list++;
+			bcopy(hp->h_addr_list[0], &sin.sin_addr, hp->h_length);
+			(void)fprintf(stderr, "Trying %s...\n",
+			    inet_ntoa(sin.sin_addr));
+			continue;
+		}
+		(void)fprintf(stderr, "%s: %s\n", hp->h_name, strerror(errno));
+		sigsetmask(oldmask);
+		return (-1);
+	}
+	lport--;
+	if (fd2p == 0) {
+		write(s, "", 1);
+		lport = 0;
+	} else {
+		char num[8];
+		int s2 = rresvport(&lport), s3;
+		int len = sizeof(from);
+
+		if (s2 < 0)
+			goto bad;
+		listen(s2, 1);
+		(void)snprintf(num, sizeof(num), "%d", lport);
+		if (write(s, num, strlen(num)+1) != strlen(num)+1) {
+			(void)fprintf(stderr,
+			    "rcmd: write (setting up stderr): %s\n",
+			    strerror(errno));
+			(void)close(s2);
+			goto bad;
+		}
+		FD_ZERO(&reads);
+		FD_SET(s, &reads);
+		FD_SET(s2, &reads);
+		errno = 0;
+		if (select(1 + (s > s2 ? s : s2), &reads, 0, 0, 0) < 1 ||
+		    !FD_ISSET(s2, &reads)) {
+			if (errno != 0)
+				(void)fprintf(stderr,
+				    "rcmd: select (setting up stderr): %s\n",
+				    strerror(errno));
+			else
+				(void)fprintf(stderr,
+				"select: protocol failure in circuit setup\n");
+			(void)close(s2);
+			goto bad;
+		}
+		s3 = accept(s2, (struct sockaddr *)&from, &len);
+		(void)close(s2);
+		if (s3 < 0) {
+			(void)fprintf(stderr,
+			    "rcmd: accept: %s\n", strerror(errno));
+			lport = 0;
+			goto bad;
+		}
+		*fd2p = s3;
+		from.sin_port = ntohs((u_short)from.sin_port);
+		if (from.sin_family != AF_INET ||
+		    from.sin_port >= IPPORT_RESERVED ||
+		    from.sin_port < IPPORT_RESERVED / 2) {
+			(void)fprintf(stderr,
+			    "socket: protocol failure in circuit setup.\n");
+			goto bad2;
+		}
+	}
+	(void)write(s, locuser, strlen(locuser)+1);
+	(void)write(s, remuser, strlen(remuser)+1);
+	(void)write(s, cmd, strlen(cmd)+1);
+	if (read(s, &c, 1) != 1) {
+		(void)fprintf(stderr,
+		    "rcmd: %s: %s\n", *ahost, strerror(errno));
+		goto bad2;
+	}
+	if (c != 0) {
+		while (read(s, &c, 1) == 1) {
+			(void)write(STDERR_FILENO, &c, 1);
+			if (c == '\n')
+				break;
+		}
+		goto bad2;
+	}
+	sigsetmask(oldmask);
+	return (s);
+bad2:
+	if (lport)
+		(void)close(*fd2p);
+bad:
+	(void)close(s);
+	sigsetmask(oldmask);
+	return (-1);
+}
+
+int
+rresvport(alport)
+	int *alport;
+{
+	struct sockaddr_in sin;
+	int s;
+
+	sin.sin_family = AF_INET;
+	sin.sin_addr.s_addr = INADDR_ANY;
+	s = socket(AF_INET, SOCK_STREAM, 0);
+	if (s < 0)
+		return (-1);
+	for (;;) {
+		sin.sin_port = htons((u_short)*alport);
+		if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
+			return (s);
+		if (errno != EADDRINUSE) {
+			(void)close(s);
+			return (-1);
+		}
+		(*alport)--;
+		if (*alport == IPPORT_RESERVED/2) {
+			(void)close(s);
+			errno = EAGAIN;		/* close */
+			return (-1);
+		}
+	}
+}
+
+int	__check_rhosts_file = 1;
+char	*__rcmd_errstr;
+
+int
+ruserok(rhost, superuser, ruser, luser)
+	const char *rhost, *ruser, *luser;
+	int superuser;
+{
+	struct hostent *hp;
+	u_long addr;
+	char **ap;
+
+	if ((hp = gethostbyname(rhost)) == NULL)
+		return (-1);
+	for (ap = hp->h_addr_list; *ap; ++ap) {
+		bcopy(*ap, &addr, sizeof(addr));
+		if (iruserok(addr, superuser, ruser, luser) == 0)
+			return (0);
+	}
+	return (-1);
+}
+
+/*
+ * New .rhosts strategy: We are passed an ip address. We spin through
+ * hosts.equiv and .rhosts looking for a match. When the .rhosts only
+ * has ip addresses, we don't have to trust a nameserver.  When it
+ * contains hostnames, we spin through the list of addresses the nameserver
+ * gives us and look for a match.
+ *
+ * Returns 0 if ok, -1 if not ok.
+ */
+int
+iruserok(raddr, superuser, ruser, luser)
+	u_long raddr;
+	int superuser;
+	const char *ruser, *luser;
+{
+	register char *cp;
+	struct stat sbuf;
+	struct passwd *pwd;
+	FILE *hostf;
+	uid_t uid;
+	int first;
+
+	first = 1;
+	hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "r");
+again:
+	if (hostf) {
+		if (__ivaliduser(hostf, raddr, luser, ruser) == 0) {
+			(void)fclose(hostf);
+			return (0);
+		}
+		(void)fclose(hostf);
+	}
+	if (first == 1 && (__check_rhosts_file || superuser)) {
+		char *pbuf;
+		size_t dirlen;
+
+		first = 0;
+		if ((pwd = getpwnam(luser)) == NULL)
+			return (-1);
+
+		dirlen = strlen (pwd->pw_dir);
+		pbuf = alloca (dirlen + sizeof "/.rhosts");
+		memcpy (pbuf, pwd->pw_dir, dirlen);
+		memcpy (pbuf + dirlen, "/.rhosts", sizeof "/.rhosts");
+
+		/*
+		 * Change effective uid while opening .rhosts.  If root and
+		 * reading an NFS mounted file system, can't read files that
+		 * are protected read/write owner only.
+		 */
+		uid = geteuid();
+		(void)seteuid(pwd->pw_uid);
+		hostf = fopen(pbuf, "r");
+		(void)seteuid(uid);
+
+		if (hostf == NULL)
+			return (-1);
+		/*
+		 * If not a regular file, or is owned by someone other than
+		 * user or root or if writeable by anyone but the owner, quit.
+		 */
+		cp = NULL;
+		if (lstat(pbuf, &sbuf) < 0)
+			cp = ".rhosts lstat failed";
+		else if (!S_ISREG(sbuf.st_mode))
+			cp = ".rhosts not regular file";
+		else if (fstat(fileno(hostf), &sbuf) < 0)
+			cp = ".rhosts fstat failed";
+		else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
+			cp = "bad .rhosts owner";
+		else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
+			cp = ".rhosts writeable by other than owner";
+		/* If there were any problems, quit. */
+		if (cp) {
+			__rcmd_errstr = cp;
+			(void)fclose(hostf);
+			return (-1);
+		}
+		goto again;
+	}
+	return (-1);
+}
+
+/*
+ * XXX
+ * Don't make static, used by lpd(8).
+ *
+ * Returns 0 if ok, -1 if not ok.
+ */
+int
+__ivaliduser(hostf, raddr, luser, ruser)
+	FILE *hostf;
+	u_long raddr;
+	const char *luser, *ruser;
+{
+	register char *user, *p;
+	int ch;
+	char *buf = NULL;
+	size_t bufsize = 0;
+	ssize_t nread;
+
+	while ((nread = getline (&buf, &bufsize, hostf)) > 0) {
+		buf[bufsize - 1] = '\0'; /* Make sure it's terminated.  */
+		p = buf;
+		while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
+			*p = isupper(*p) ? tolower(*p) : *p;
+			p++;
+		}
+		if (*p == ' ' || *p == '\t') {
+			*p++ = '\0';
+			while (*p == ' ' || *p == '\t')
+				p++;
+			user = p;
+			while (*p != '\n' && *p != ' ' &&
+			    *p != '\t' && *p != '\0')
+				p++;
+		} else
+			user = p;
+		*p = '\0';
+		if (__icheckhost(raddr, buf) &&
+		    strcmp(ruser, *user ? user : luser) == 0) {
+			free (buf);
+			return (0);
+		}
+	}
+	free (buf);
+	return (-1);
+}
+
+/*
+ * Returns "true" if match, 0 if no match.
+ */
+static int
+__icheckhost(raddr, lhost)
+	u_long raddr;
+	register char *lhost;
+{
+	register struct hostent *hp;
+	register u_long laddr;
+	register char **pp;
+
+	/* Try for raw ip address first. */
+	if (isdigit(*lhost) && (long)(laddr = inet_addr(lhost)) != -1)
+		return (raddr == laddr);
+
+	/* Better be a hostname. */
+	if ((hp = gethostbyname(lhost)) == NULL)
+		return (0);
+
+	/* Spin through ip addresses. */
+	for (pp = hp->h_addr_list; *pp; ++pp)
+		if (!bcmp(&raddr, *pp, sizeof(u_long)))
+			return (1);
+
+	/* No match. */
+	return (0);
+}