cmd-inet/usr.bin/rcp.c

/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

/*
 * Copyright (c) 1983 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 */

#define	_FILE_OFFSET_BITS  64

/*
 * rcp
 */
#include <sys/param.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/acl.h>
#include <dirent.h>
#include <signal.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <pwd.h>
#include <netdb.h>
#include <wchar.h>
#include <stdlib.h>
#include <errno.h>
#include <locale.h>
#include <strings.h>
#include <stdio.h>
#include <ctype.h>
#include <fcntl.h>
#include <unistd.h>
#include <limits.h>
#include <priv_utils.h>
#include <sys/sendfile.h>
#include <sys/sysmacros.h>
#include <sys/wait.h>
#include <aclutils.h>
#include <sys/varargs.h>

/*
 * It seems like Berkeley got these from pathnames.h?
 */
#define	_PATH_RSH	"/usr/bin/rsh"
#define	_PATH_CP	"/usr/bin/cp"

#define	ACL_FAIL	1
#define	ACL_OK		0
#define	RCP_BUFSIZE	(64 * 1024)

#define	RCP_ACL	"/usr/lib/sunw,rcp"
		/* see PSARC/1993/004/opinion */

typedef struct _buf {
	int	cnt;
	char	*buf;
} BUF;

static char *cmd_sunw;
static struct passwd *pwd;
static int errs;
static int pflag;
static uid_t userid;
static int rem;
static int zflag;
static int iamremote;
static int iamrecursive;
static int targetshouldbedirectory;
static int aclflag;
static int acl_aclflag;
static int retval = 0;
static int portnumber = 0;

static void lostconn(void);
static char *search_char(unsigned char *, unsigned char);
static char *removebrackets(char *);
static char *colon(char *);
static int response(void);
static void usage(void);
static void source(int, char **);
static void sink(int, char **);
static void toremote(char *, int, char **);
static void tolocal(int, char **);
static void verifydir(char *);
static int okname(char *);
static int susystem(char *, char **);
static void rsource(char *, struct stat *);
static int sendacl(int);
static int recvacl(int, int, int);
static int zwrite(int, char *, int);
static void zopen(int, int);
static int zclose(int);
static int notzero(char *, int);
static BUF *allocbuf(BUF *, int, int);
static void error(char *fmt, ...);
static void addargs(char **, ...);

/*
 * As a 32 bit application, we can only transfer (2gb - 1) i.e 0x7FFFFFFF
 * bytes of data. We would like the size to be aligned to the nearest
 * MAXBOFFSET (8192) boundary for optimal performance.
 */
#define	SENDFILE_SIZE	0x7FFFE000

#include <k5-int.h>
#include <profile/prof_int.h>
#include <com_err.h>
#include <kcmd.h>

#define	NULLBUF	(BUF *) 0
#define	MAXARGS	10	/* Number of arguments passed to execv() */

static int sock;
static char *cmd, *cmd_orig, *cmd_sunw_orig;
static char *krb_realm = NULL;
static char *krb_cache = NULL;
static char *krb_config = NULL;
static char des_inbuf[2 * RCP_BUFSIZE];
				/* needs to be > largest read size */
static char des_outbuf[2 * RCP_BUFSIZE];
				/* needs to be > largest write size */

static krb5_data desinbuf, desoutbuf;
static krb5_encrypt_block eblock;	/* eblock for encrypt/decrypt */
static krb5_keyblock *session_key;	/* static key for session */
static krb5_context bsd_context;
static krb5_auth_context auth_context;
static krb5_flags authopts;
static krb5_error_code status;

static void try_normal_rcp(int, char **);
static int init_service(int);
static char **save_argv(int, char **);
static void answer_auth(char *, char *);
static int desrcpwrite(int, char *, int);
static int desrcpread(int, char *, int);

/*
 * Not sure why these two don't have their own header file declarations, but
 * lint complains about absent declarations so place some here. Sigh.
 */
extern errcode_t	profile_get_options_boolean(profile_t, char **,
    profile_options_boolean *);
extern errcode_t	profile_get_options_string(profile_t, char **,
    profile_option_strings *);

static int krb5auth_flag = 0;	/* Flag set, when KERBEROS is enabled */
static int encrypt_flag = 0;	/* Flag set, when encryption is enabled */
static int encrypt_done = 0;	/* Flag set, if "-x" is specified */
static enum kcmd_proto kcmd_proto = KCMD_NEW_PROTOCOL;

/* Flag set, if -PN / -PO is specified */
static boolean_t rcmdoption_done = B_FALSE;

static profile_options_boolean option[] = {
	{ "encrypt", &encrypt_flag, 0 },
	{ NULL, NULL, 0 }
};

static char *rcmdproto = NULL;
static profile_option_strings rcmdversion[] = {
	{ "rcmd_protocol", &rcmdproto, 0 },
	{ NULL, NULL, 0 }
};

static char *realmdef[] = { "realms", NULL, "rcp", NULL };
static char *appdef[] = { "appdefaults", "rcp", NULL };
static char **prev_argv;
static int prev_argc;

int
main(int argc, char *argv[])
{
	int ch, fflag, tflag;
	char *targ;
	size_t cmdsiz;

	(void) setlocale(LC_ALL, "");

	if (strcmp(argv[0], RCP_ACL) == 0)
		aclflag = 1;

	if (!(pwd = getpwuid(userid = getuid()))) {
		(void) fprintf(stderr, "rcp: unknown user %d.\n",
		    (uint_t)userid);
		return (1);
	}

	fflag = tflag = 0;
	while ((ch = getopt(argc, argv, "axdfprtz:D:k:P:Z")) != EOF) {
		switch (ch) {
		case 'd':
			targetshouldbedirectory = 1;
			break;
		case 'f':			/* "from" */
			fflag = 1;
			if (aclflag | acl_aclflag)
				/* ok response */
				(void) desrcpwrite(rem, "", 1);
			break;
		case 'p':			/* preserve access/mod times */
			++pflag;
			break;
		case 'r':
			++iamrecursive;
			break;
		case 't':			/* "to" */
			tflag = 1;
			break;
		case 'Z':
			acl_aclflag++;
			break;
		case 'x':
			if (!krb5_privacy_allowed()) {
				(void) fprintf(stderr, gettext("rcp: "
					"Encryption not supported.\n"));
				return (1);
			}
			encrypt_flag++;
			krb5auth_flag++;
			encrypt_done++;
			break;
		case 'k':
			if ((krb_realm = (char *)strdup(optarg)) == NULL) {
				(void) fprintf(stderr, gettext("rcp:"
					" Cannot malloc.\n"));
				return (1);
			}
			krb5auth_flag++;
			break;
		case 'P':
			if (strncmp(optarg, "O", 1) == 0) {
				if (rcmdoption_done == B_TRUE) {
					(void) fprintf(stderr, gettext("rcp: "
						"Only one of -PN and -PO "
						"allowed.\n"));
					usage();
				}
				kcmd_proto = KCMD_OLD_PROTOCOL;
				rcmdoption_done = B_TRUE;
			} else if (strncmp(optarg, "N", 1) == 0) {
				if (rcmdoption_done == B_TRUE) {
					(void) fprintf(stderr, gettext("rcp: "
						"Only one of -PN and -PO "
						"allowed.\n"));
					usage();
				}
				kcmd_proto = KCMD_NEW_PROTOCOL;
				rcmdoption_done = B_TRUE;
			} else {
				usage();
			}
			krb5auth_flag++;
			break;
		case 'a':
			krb5auth_flag++;
			break;
#ifdef DEBUG
		case 'D':
			portnumber = htons(atoi(optarg));
			krb5auth_flag++;
			break;
#endif /* DEBUG */
		case '?':
		default:
			usage();
		}
	}
	argc -= optind;
	argv += optind;

	if (krb5auth_flag > 0) {
		status = krb5_init_context(&bsd_context);
		if (status) {
			com_err("rcp", status,
				gettext("while initializing krb5"));
			return (1);
		}

		/*
		 * Set up buffers for desread and deswrite.
		 */
		desinbuf.data = des_inbuf;
		desoutbuf.data = des_outbuf;
		desinbuf.length = sizeof (des_inbuf);
		desoutbuf.length = sizeof (des_outbuf);
	}

	if (fflag || tflag)
		if (encrypt_flag > 0)
			(void) answer_auth(krb_config, krb_cache);

	if (fflag) {
		iamremote = 1;
		(void) response();
		(void) setuid(userid);
		source(argc, argv);
		return (errs);
	}

	if (tflag) {
		iamremote = 1;
		(void) setuid(userid);
		sink(argc, argv);
		return (errs);
	}

	if (argc < 2)
		usage();

	/* This will make "rcmd_af()" magically get the proper privilege */
	if (__init_suid_priv(0, PRIV_NET_PRIVADDR, (char *)NULL) == -1) {
		(void) fprintf(stderr, "rcp: must be set-uid root\n");
		exit(1);
	}

	if (krb5auth_flag > 0) {
		/*
		 * Get our local realm to look up local realm options.
		 */
		status = krb5_get_default_realm(bsd_context, &realmdef[1]);
		if (status) {
			com_err("rcp", status,
				gettext("while getting default realm"));
			return (1);
		}
		/*
		 * See if encryption should be done for this realm
		 */
		profile_get_options_boolean(bsd_context->profile, realmdef,
						option);
		/*
		 * Check the appdefaults section
		 */
		profile_get_options_boolean(bsd_context->profile, appdef,
						option);
		profile_get_options_string(bsd_context->profile, appdef,
						rcmdversion);
		if ((encrypt_done > 0) || (encrypt_flag > 0)) {
			if (krb5_privacy_allowed() == TRUE) {
				encrypt_flag++;
			} else {
				(void) fprintf(stderr, gettext("rcp: Encryption"
							" not supported.\n"));
				return (1);
			}
		}

		if ((rcmdoption_done == B_FALSE) && (rcmdproto != NULL)) {
			if (strncmp(rcmdproto, "rcmdv2", 6) == 0) {
				kcmd_proto = KCMD_NEW_PROTOCOL;
			} else if (strncmp(rcmdproto, "rcmdv1", 6) == 0) {
				kcmd_proto = KCMD_OLD_PROTOCOL;
			} else {
				(void) fprintf(stderr, gettext("Unrecognized "
					"KCMD protocol (%s)"), rcmdproto);
				return (1);
			}
		}
	}

	if (argc > 2)
		targetshouldbedirectory = 1;

	rem = -1;

	if (portnumber == 0) {
		if (krb5auth_flag > 0) {
			retval = init_service(krb5auth_flag);
			if (!retval) {
				/*
				 * Connecting to the kshell service failed,
				 * fallback to normal rcp & reset KRB5 flags.
				 */
				krb5auth_flag = encrypt_flag = 0;
				encrypt_done = 0;
				(void) init_service(krb5auth_flag);
			}
		}
		else
			(void) init_service(krb5auth_flag);
	}

#ifdef DEBUG
	if (retval || krb5auth_flag) {
		(void) fprintf(stderr, gettext("Kerberized rcp session, "
				"port %d in use "), portnumber);
		if (kcmd_proto == KCMD_OLD_PROTOCOL)
			(void) fprintf(stderr, gettext("[kcmd ver.1]\n"));
		else
			(void) fprintf(stderr, gettext("[kcmd ver.2]\n"));
	} else {
		(void) fprintf(stderr, gettext("Normal rcp session, port %d "
				"in use.\n"), portnumber);
	}
#endif /* DEBUG */

	if (krb5auth_flag > 0) {
		/*
		 * We calculate here a buffer size that can be used in the
		 * allocation of the three buffers cmd, cmd_orig and
		 * cmd_sunw_orig that are used to hold different incantations
		 * of rcp.
		 */
		cmdsiz = MAX(sizeof ("-x rcp -r -p -d -k ") +
		    strlen(krb_realm != NULL ? krb_realm : ""),
		    sizeof (RCP_ACL " -r -p -z -d"));

		if (((cmd = (char *)malloc(cmdsiz)) == NULL) ||
			((cmd_sunw_orig = (char *)malloc(cmdsiz)) == NULL) ||
			((cmd_orig = (char *)malloc(cmdsiz)) == NULL)) {
			(void) fprintf(stderr, gettext("rcp: Cannot "
					"malloc.\n"));
			return (1);
		}

		(void) snprintf(cmd, cmdsiz, "%srcp %s%s%s%s%s",
			encrypt_flag ? "-x " : "",
			iamrecursive ? " -r" : "", pflag ? " -p" : "",
			targetshouldbedirectory ? " -d" : "",
			krb_realm != NULL ? " -k " : "",
			krb_realm != NULL ? krb_realm : "");

		/*
		 * We would use cmd-orig as the 'cmd-buffer' if kerberized
		 * rcp fails, in which case we fallback to normal rcp. We also
		 * save argc & argv for the same purpose
		 */
		(void) snprintf(cmd_orig, cmdsiz, "rcp%s%s%s%s",
			iamrecursive ? " -r" : "",
			pflag ? " -p" : "",
			zflag ? " -z" : "",
			targetshouldbedirectory ? " -d" : "");

		(void) snprintf(cmd_sunw_orig, cmdsiz, "%s%s%s%s%s", RCP_ACL,
			iamrecursive ? " -r" : "",
			pflag ? " -p" : "",
			zflag ? " -z" : "",
			targetshouldbedirectory ? " -d" : "");

		prev_argc = argc;
		prev_argv = save_argv(argc, argv);

	} else {
		cmdsiz = sizeof ("rcp -r -p -z -d");
		if (((cmd = (char *)malloc(cmdsiz)) == NULL)) {
			(void) fprintf(stderr, gettext("rcp: Cannot "
					"malloc.\n"));
			return (1);
		}

		(void) snprintf(cmd, cmdsiz, "rcp%s%s%s%s",
			iamrecursive ? " -r" : "",
			pflag ? " -p" : "",
			zflag ? " -z" : "",
			targetshouldbedirectory ? " -d" : "");
	}

	cmdsiz = sizeof (RCP_ACL " -r -p -z -d");
	if ((cmd_sunw = (char *)malloc(cmdsiz)) == NULL) {
		(void) fprintf(stderr, gettext("rcp: Cannot malloc.\n"));
		return (1);
	}

	(void) snprintf(cmd_sunw, cmdsiz, "%s%s%s%s%s", RCP_ACL,
	    iamrecursive ? " -r" : "",
	    pflag ? " -p" : "",
	    zflag ? " -z" : "",
	    targetshouldbedirectory ? " -d" : "");

	(void) signal(SIGPIPE, (void (*)(int))lostconn);

	if (targ = colon(argv[argc - 1]))
		toremote(targ, argc, argv);
	else {
		tolocal(argc, argv);
		if (targetshouldbedirectory)
			verifydir(argv[argc - 1]);
	}

	return (errs > 0 ? EXIT_FAILURE : EXIT_SUCCESS);
}


static void
toremote(char *targ, int argc, char *argv[])
{
	int i;
	char *host, *src, *suser, *thost, *tuser;
	char resp;
	size_t buffersize;
	char bp[RCP_BUFSIZE];
	krb5_creds *cred;
	char *arglist[MAXARGS+1];
	buffersize = RCP_BUFSIZE;

	*targ++ = 0;
	if (*targ == 0)
		targ = ".";

	if (thost = search_char((unsigned char *)argv[argc - 1], '@')) {
		*thost++ = 0;
		tuser = argv[argc - 1];
		if (*tuser == '\0')
			tuser = NULL;
		else if (!okname(tuser))
			exit(1);
	} else {
		thost = argv[argc - 1];
		tuser = NULL;
	}
	thost = removebrackets(thost);

	for (i = 0; i < argc - 1; i++) {
		src = colon(argv[i]);
		if (src) {			/* remote to remote */
			*src++ = 0;
			if (*src == 0)
				src = ".";
			host = search_char((unsigned char *)argv[i], '@');
			if (host) {
				*host++ = 0;
				host = removebrackets(host);
				suser = argv[i];
				if (*suser == '\0') {
					suser = pwd->pw_name;
				} else if (!okname(suser)) {
					errs++;
					continue;
				}
				(void) snprintf(bp, buffersize, "'%s%s%s:%s'",
				    tuser ? tuser : "", tuser ? "@" : "",
				    thost, targ);
				(void) addargs(arglist, "rsh", host, "-l",
				    suser, "-n", cmd, src, bp, (char *)NULL);
			} else {
				host = removebrackets(argv[i]);
				(void) snprintf(bp, buffersize, "'%s%s%s:%s'",
				    tuser ? tuser : "", tuser ? "@" : "",
				    thost, targ);
				(void) addargs(arglist, "rsh", host, "-n", cmd,
				    src, bp, (char *)NULL);
			}
			if (susystem(_PATH_RSH, arglist) == -1)
				errs++;
		} else {			/* local to remote */
			if (rem == -1) {
				host = thost;
				if (krb5auth_flag > 0) {

				(void) snprintf(bp, buffersize,
						"%s -t %s", cmd, targ);
				authopts = AP_OPTS_MUTUAL_REQUIRED;
				status = kcmd(&sock, &host,
					    portnumber,
					    pwd->pw_name,
					    tuser ? tuser :
					    pwd->pw_name,
					    bp,
					    0,
					    "host",
					    krb_realm,
					    bsd_context,
					    &auth_context,
					    &cred,
					    0,	/* No seq # */
					    0,	/* No server seq # */
					    authopts,
					    0,	/* Not any port # */
					    &kcmd_proto);
				if (status) {
					/*
					 * If new protocol requested, we dont
					 * fallback to less secure ones.
					 */

					if (kcmd_proto == KCMD_NEW_PROTOCOL) {
						(void) fprintf(stderr,
							gettext("rcp: kcmdv2 "
							"to host %s failed - %s"
							"\nFallback to normal "
							"rcp denied."), host,
							error_message(status));
						exit(1);
					}
					if (status != -1) {
						(void) fprintf(stderr,
						gettext("rcp: kcmd to host "
						"%s failed - %s,\n"
						"trying normal rcp...\n\n"),
						host, error_message(status));
					} else {
						(void) fprintf(stderr,
							gettext("trying normal"
							" rcp...\n"));
					}
					/*
					 * kcmd() failed, so we have to
					 * fallback to normal rcp
					 */
					try_normal_rcp(prev_argc, prev_argv);
				} else {
					rem = sock;
					session_key = &cred->keyblock;
					if (kcmd_proto == KCMD_NEW_PROTOCOL) {
						/* CSTYLED */
						status = krb5_auth_con_getlocalsubkey(bsd_context, auth_context, &session_key);
						if (status) {
							com_err("rcp", status,
								"determining "
								"subkey for "
								"session");
							exit(1);
						}
						if (!session_key) {
							com_err("rcp", 0,
								"no subkey "
								"negotiated for"
								" connection");
							exit(1);
						}
					}
					eblock.crypto_entry =
						session_key->enctype;
					eblock.key =
						(krb5_keyblock *)session_key;

					init_encrypt(encrypt_flag,
						bsd_context, kcmd_proto,
						&desinbuf, &desoutbuf, CLIENT,
						&eblock);
					if (encrypt_flag > 0) {
						char *s = gettext("This rcp "
							"session is using "
							"encryption for all "
							"data transmissions."
							"\r\n");

						(void) write(2, s, strlen(s));
					}
				}
				if (response() < 0)
					exit(1);

				} else {

				/*
				 * ACL support: try to find out if the remote
				 * site is running acl cognizant version of
				 * rcp. A special binary name is used for this
				 * purpose.
				 */
				aclflag = 1;
				acl_aclflag = 1;

				/*
				 * First see if the remote side will support
				 * both aclent_t and ace_t acl's?
				 */
				(void) snprintf(bp, buffersize, "%s -tZ %s",
							cmd_sunw, targ);
				rem = rcmd_af(&host, portnumber, pwd->pw_name,
					    tuser ? tuser : pwd->pw_name,
					    bp, 0, AF_INET6);
				if (rem < 0)
					exit(1);

				/*
				 * This is similar to routine response().
				 * If response is not ok, treat the other
				 * side as non-acl rcp.
				 */
				if (read(rem, &resp, sizeof (resp))
				    != sizeof (resp))
					lostconn();
				if (resp != 0) {
					acl_aclflag = 0;
					(void) snprintf(bp, buffersize,
					    "%s -t %s", cmd_sunw, targ);

					(void) close(rem);
					host = thost;
					rem = rcmd_af(&host, portnumber,
					    pwd->pw_name,
					    tuser ? tuser : pwd->pw_name,
					    bp, 0, AF_INET6);
					if (rem < 0)
						exit(1);

					if (read(rem, &resp, sizeof (resp))
					    != sizeof (resp))
						lostconn();
					if (resp != 0) {
						/*
						 * Not OK:
						 * The other side is running
						 * non-acl rcp. Try again with
						 * normal stuff
						 */
						aclflag = 0;
						(void) snprintf(bp, buffersize,
						    "%s -t %s", cmd, targ);
						(void) close(rem);
						host = thost;
						rem = rcmd_af(&host, portnumber,
						    pwd->pw_name,
						    tuser ? tuser :
						    pwd->pw_name, bp, 0,
						    AF_INET6);
						if (rem < 0)
							exit(1);
						if (response() < 0)
						    exit(1);
					}
				}
				/* everything should be fine now */
				(void) setuid(userid);

				}
			}
			source(1, argv + i);
		}
	}
}

static void
tolocal(int argc, char *argv[])
{
	int i;
	char *host, *src, *suser, *lhost;
	char resp;
	size_t buffersize;
	char bp[RCP_BUFSIZE];
	krb5_creds *cred;
	char *arglist[MAXARGS+1];
	buffersize = RCP_BUFSIZE;

	for (i = 0; i < argc - 1; i++) {
		if (!(src = colon(argv[i]))) {	/* local to local */
			(void) addargs(arglist, "cp",
			    iamrecursive ? "-r" : "", pflag ? "-p" : "",
			    zflag ? "-z" : "", argv[i], argv[argc - 1],
			    (char *)NULL);
			if (susystem(_PATH_CP, arglist) == -1)
				errs++;
			continue;
		}
		*src++ = 0;
		if (*src == 0)
			src = ".";
		host = search_char((unsigned char *)argv[i], '@');
		if (host) {
			*host++ = 0;
			suser = argv[i];
			if (*suser == '\0') {
				suser = pwd->pw_name;
			} else if (!okname(suser)) {
				errs++;
				continue;
			}
		} else {
			host = argv[i];
			suser = pwd->pw_name;
		}
		host = removebrackets(host);
		lhost = host;
		if (krb5auth_flag > 0) {

		(void) snprintf(bp, buffersize, "%s -f %s", cmd, src);
		authopts = AP_OPTS_MUTUAL_REQUIRED;
		status = kcmd(&sock, &host,
				portnumber,
				pwd->pw_name, suser,
				bp,
				0,	/* &rfd2 */
				"host",
				krb_realm,
				bsd_context,
				&auth_context,
				&cred,
				0,	/* No seq # */
				0,	/* No server seq # */
				authopts,
				1,	/* Not any port # */
				&kcmd_proto);
		if (status) {
			/*
			 * If new protocol requested, we dont
			 * fallback to less secure ones.
			 */
			if (kcmd_proto == KCMD_NEW_PROTOCOL) {
				(void) fprintf(stderr, gettext("rcp: kcmdv2 "
					"to host %s failed - %s\n"
					"Fallback to normal rcp denied."),
					host, error_message(status));
				exit(1);
			}
			if (status != -1) {
				(void) fprintf(stderr, gettext("rcp: kcmd "
						"to host %s failed - %s,\n"
						"trying normal rcp...\n\n"),
						host, error_message(status));
			} else {
				(void) fprintf(stderr,
					gettext("trying normal rcp...\n"));
			}
			/*
			 * kcmd() failed, so we have to
			 * fallback to normal rcp
			 */
			try_normal_rcp(prev_argc, prev_argv);
		} else {
			rem = sock;
			session_key = &cred->keyblock;
			if (kcmd_proto == KCMD_NEW_PROTOCOL) {
				status = krb5_auth_con_getlocalsubkey(
						bsd_context, auth_context,
						&session_key);
				if (status) {
					com_err("rcp", status, "determining "
						"subkey for session");
					exit(1);
				}
				if (!session_key) {
					com_err("rcp", 0, "no subkey negotiated"
						" for connection");
					exit(1);
				}
			}
			eblock.crypto_entry = session_key->enctype;
			eblock.key = (krb5_keyblock *)session_key;

			init_encrypt(encrypt_flag, bsd_context, kcmd_proto,
					&desinbuf, &desoutbuf, CLIENT,
					&eblock);
			if (encrypt_flag > 0) {
				char *s = gettext("This rcp "
					"session is using DES "
					"encryption for all "
					"data transmissions."
					"\r\n");

				(void) write(2, s, strlen(s));
			}
		}

		}
		else
		{

		/*
		 * ACL support: try to find out if the remote site is
		 * running acl cognizant version of rcp.
		 */
		aclflag = 1;
		acl_aclflag = 1;

		(void) snprintf(bp, buffersize, "%s -Zf %s", cmd_sunw, src);
		rem = rcmd_af(&host, portnumber, pwd->pw_name, suser,
			    bp, 0, AF_INET6);

		if (rem < 0) {
			++errs;
			continue;
		}

		/*
		 * The remote system is supposed to send an ok response.
		 * If there are any data other than "ok", it must be error
		 * messages from the remote system. We can assume the
		 * remote system is running non-acl version rcp.
		 */
		if (read(rem, &resp, sizeof (resp)) != sizeof (resp))
			lostconn();
		if (resp != 0) {

			/*
			 * Try again without ace_acl support
			 */
			acl_aclflag = 0;
			(void) snprintf(bp, buffersize, "%s -f %s",
			    cmd_sunw, src);
			rem = rcmd_af(&host, portnumber, pwd->pw_name, suser,
			    bp, 0, AF_INET6);

			if (rem < 0) {
				++errs;
				continue;
			}

			if (read(rem, &resp, sizeof (resp)) != sizeof (resp))
				lostconn();

			/*
			 * NOT ok:
			 * The other side is running non-acl rcp.
			 * Try again with normal stuff
			 */
			aclflag = 0;
			(void) snprintf(bp, buffersize, "%s -f %s", cmd, src);
				(void) close(rem);
				host = lhost;
				rem = rcmd_af(&host, portnumber, pwd->pw_name,
						suser, bp, 0, AF_INET6);
			if (rem < 0) {
				++errs;
				continue;
			}
		}
		}

		sink(1, argv + argc - 1);

		(void) close(rem);
		rem = -1;
	}
}


static void
verifydir(char *cp)
{
	struct stat stb;

	if (stat(cp, &stb) >= 0) {
		if ((stb.st_mode & S_IFMT) == S_IFDIR)
			return;
		errno = ENOTDIR;
	}
	error("rcp: %s: %s.\n", cp, strerror(errno));
	exit(1);
}

static char *
colon(char *cp)
{
	boolean_t is_bracket_open = B_FALSE;

	for (; *cp; ++cp) {
		if (*cp == '[')
			is_bracket_open = B_TRUE;
		else if (*cp == ']')
			is_bracket_open = B_FALSE;
		else if (*cp == ':' && !is_bracket_open)
			return (cp);
		else if (*cp == '/')
			return (0);
	}
	return (0);
}

static int
okname(char *cp0)
{
	register char *cp = cp0;
	register int c;

	do {
		c = *cp;
		if (c & 0200)
			goto bad;
		if (!isalpha(c) && !isdigit(c) && c != '_' && c != '-')
			goto bad;
	} while (*++cp);
	return (1);
bad:
	(void) fprintf(stderr, "rcp: invalid user name %s\n", cp0);
	return (0);
}


static char *
removebrackets(char *str)
{
	char *newstr = str;

	if ((str[0] == '[') && (str[strlen(str) - 1] == ']')) {
		newstr = str + 1;
		str[strlen(str) - 1] = '\0';
	}
	return (newstr);
}

static int
susystem(char *path, char **arglist)
{
	int status, pid, w;
	register void (*istat)(), (*qstat)();
	int pfds[2];
	char buf[BUFSIZ];
	int cnt;
	boolean_t seen_stderr_traffic;

	/*
	 * Due to the fact that rcp uses rsh to copy between 2 remote
	 * machines, rsh doesn't return the exit status of the remote
	 * command, and we can't modify the rcmd protocol used by rsh
	 * (for interoperability reasons) we use the hack of using any
	 * output on stderr as indication that an error occurred and
	 * that we should return a non-zero error code.
	 */

	if (pipe(pfds) == -1) {
		(void) fprintf(stderr, "Couldn't create pipe: %s\n",
		    strerror(errno));
		return (-1);
	}

	if ((pid = vfork()) < 0) {
		(void) close(pfds[0]);
		(void) close(pfds[1]);
		(void) fprintf(stderr, "Couldn't fork child process: %s\n",
		    strerror(errno));
		return (-1);
	} else if (pid == 0) {
		/*
		 * Child.
		 */
		(void) close(pfds[0]);
		/*
		 * Send stderr messages down the pipe so that we can detect
		 * them in the parent process.
		 */
		if (pfds[1] != STDERR_FILENO) {
			(void) dup2(pfds[1], STDERR_FILENO);
			(void) close(pfds[1]);
		}
		/*
		 * This shell does not inherit the additional privilege
		 * we have in our Permitted set.
		 */
		(void) execv(path, arglist);
		_exit(127);
	}
	/*
	 * Parent.
	 */
	istat = signal(SIGINT, SIG_IGN);
	qstat = signal(SIGQUIT, SIG_IGN);

	(void) close(pfds[1]);
	seen_stderr_traffic = B_FALSE;
	while ((cnt = read(pfds[0], buf, sizeof (buf))) > 0) {
		/*
		 * If any data is read from the pipe the child process
		 * has output something on stderr so we set the boolean
		 * 'seen_stderr_traffic' to true, which will cause the
		 * function to return -1.
		 */
		(void) write(STDERR_FILENO, buf, cnt);
		seen_stderr_traffic = B_TRUE;
	}
	(void) close(pfds[0]);
	while ((w = wait(&status)) != pid && w != -1)
		;
	if (w == -1)
		status = -1;

	(void) signal(SIGINT, istat);
	(void) signal(SIGQUIT, qstat);

	return (seen_stderr_traffic ? -1 : status);
}

static void
source(int argc, char *argv[])
{
	struct stat stb;
	static BUF buffer;
	BUF *bp;
	int x, readerr, f, amt;
	char *last, *name, buf[RCP_BUFSIZE];
	off_t off, size, i;
	ssize_t cnt;
	struct linger lingerbuf;

	for (x = 0; x < argc; x++) {
		name = argv[x];
		if ((f = open(name, O_RDONLY, 0)) < 0) {
			error("rcp: %s: %s\n", name, strerror(errno));
			continue;
		}
		if (fstat(f, &stb) < 0)
			goto notreg;
		switch (stb.st_mode&S_IFMT) {

		case S_IFREG:
			break;

		case S_IFDIR:
			if (iamrecursive) {
				(void) close(f);
				rsource(name, &stb);
				continue;
			}
			/* FALLTHROUGH */
		default: