openssh/sshconnect.c

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/* $OpenBSD: sshconnect.c,v 1.203 2007/12/27 14:22:08 dtucker Exp $ */
1999-10-27 03:42:43 +00:00
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Code to connect to a remote host, and to perform the client side of the
* login (authentication) dialog.
- (djm) Merge OpenBSD changes: - markus@cvs.openbsd.org 2000/09/05 02:59:57 [session.c] print hostname (not hushlogin) - markus@cvs.openbsd.org 2000/09/05 13:18:48 [authfile.c ssh-add.c] enable ssh-add -d for DSA keys - markus@cvs.openbsd.org 2000/09/05 13:20:49 [sftp-server.c] cleanup - markus@cvs.openbsd.org 2000/09/06 03:46:41 [authfile.h] prototype - deraadt@cvs.openbsd.org 2000/09/07 14:27:56 [ALL] cleanup copyright notices on all files. I have attempted to be accurate with the details. everything is now under Tatu's licence (which I copied from his readme), and/or the core-sdi bsd-ish thing for deattack, or various openbsd developers under a 2-term bsd licence. We're not changing any rules, just being accurate. - markus@cvs.openbsd.org 2000/09/07 14:40:30 [channels.c channels.h clientloop.c serverloop.c ssh.c] cleanup window and packet sizes for ssh2 flow control; ok niels - markus@cvs.openbsd.org 2000/09/07 14:53:00 [scp.c] typo - markus@cvs.openbsd.org 2000/09/07 15:13:37 [auth-options.c auth-options.h auth-rh-rsa.c auth-rsa.c auth.c] [authfile.h canohost.c channels.h compat.c hostfile.h log.c match.h] [pty.c readconf.c] some more Copyright fixes - markus@cvs.openbsd.org 2000/09/08 03:02:51 [README.openssh2] bye bye - deraadt@cvs.openbsd.org 2000/09/11 18:38:33 [LICENCE cipher.c] a few more comments about it being ARC4 not RC4 - markus@cvs.openbsd.org 2000/09/12 14:53:11 [log-client.c log-server.c log.c ssh.1 ssh.c ssh.h sshd.8 sshd.c] multiple debug levels - markus@cvs.openbsd.org 2000/09/14 14:25:15 [clientloop.c] typo - deraadt@cvs.openbsd.org 2000/09/15 01:13:51 [ssh-agent.c] check return value for setenv(3) for failure, and deal appropriately
2000-09-16 02:29:08 +00:00
*
* As far as I am concerned, the code I have written for this software
* can be used freely for any purpose. Any derived versions of this
* software must be clearly marked as such, and if the derived work is
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*/
1999-10-27 03:42:43 +00:00
#include "includes.h"
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/socket.h>
#ifdef HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
#include <netinet/in.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#ifdef HAVE_PATHS_H
#include <paths.h>
#endif
#include <pwd.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
1999-10-27 03:42:43 +00:00
#include "xmalloc.h"
- deraadt@cvs.openbsd.org 2006/08/03 03:34:42 [OVERVIEW atomicio.c atomicio.h auth-bsdauth.c auth-chall.c auth-krb5.c] [auth-options.c auth-options.h auth-passwd.c auth-rh-rsa.c auth-rhosts.c] [auth-rsa.c auth-skey.c auth.c auth.h auth1.c auth2-chall.c auth2-gss.c] [auth2-hostbased.c auth2-kbdint.c auth2-none.c auth2-passwd.c ] [auth2-pubkey.c auth2.c authfd.c authfd.h authfile.c bufaux.c bufbn.c] [buffer.c buffer.h canohost.c channels.c channels.h cipher-3des1.c] [cipher-bf1.c cipher-ctr.c cipher.c cleanup.c clientloop.c compat.c] [compress.c deattack.c dh.c dispatch.c dns.c dns.h fatal.c groupaccess.c] [groupaccess.h gss-genr.c gss-serv-krb5.c gss-serv.c hostfile.c kex.c] [kex.h kexdh.c kexdhc.c kexdhs.c kexgex.c kexgexc.c kexgexs.c key.c] [key.h log.c log.h mac.c match.c md-sha256.c misc.c misc.h moduli.c] [monitor.c monitor_fdpass.c monitor_mm.c monitor_mm.h monitor_wrap.c] [monitor_wrap.h msg.c nchan.c packet.c progressmeter.c readconf.c] [readconf.h readpass.c rsa.c scard.c scard.h scp.c servconf.c servconf.h] [serverloop.c session.c session.h sftp-client.c sftp-common.c] [sftp-common.h sftp-glob.c sftp-server.c sftp.c ssh-add.c ssh-agent.c] [ssh-dss.c ssh-gss.h ssh-keygen.c ssh-keyscan.c ssh-keysign.c ssh-rsa.c] [ssh.c ssh.h sshconnect.c sshconnect.h sshconnect1.c sshconnect2.c] [sshd.c sshlogin.c sshlogin.h sshpty.c sshpty.h sshtty.c ttymodes.c] [uidswap.c uidswap.h uuencode.c uuencode.h xmalloc.c xmalloc.h] [loginrec.c loginrec.h openbsd-compat/port-aix.c openbsd-compat/port-tun.h] almost entirely get rid of the culture of ".h files that include .h files" ok djm, sort of ok stevesk makes the pain stop in one easy step NB. portable commit contains everything *except* removing includes.h, as that will take a fair bit more work as we move headers that are required for portability workarounds to defines.h. (also, this step wasn't "easy")
2006-08-05 02:39:39 +00:00
#include "key.h"
#include "hostfile.h"
#include "ssh.h"
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#include "rsa.h"
#include "buffer.h"
1999-10-27 03:42:43 +00:00
#include "packet.h"
#include "uidswap.h"
#include "compat.h"
#include "key.h"
#include "sshconnect.h"
#include "hostfile.h"
Hopefully things did not get mixed around too much. It compiles under Linux and works. So that is at least a good sign. =) 20010122 - (bal) OpenBSD Resync - markus@cvs.openbsd.org 2001/01/19 12:45:26 GMT 2001 by markus [servconf.c ssh.h sshd.c] only auth-chall.c needs #ifdef SKEY - markus@cvs.openbsd.org 2001/01/19 15:55:10 GMT 2001 by markus [auth-krb4.c auth-options.c auth-rh-rsa.c auth-rhosts.c auth-rsa.c auth1.c auth2.c channels.c clientloop.c dh.c dispatch.c nchan.c packet.c pathname.h readconf.c scp.c servconf.c serverloop.c session.c ssh-add.c ssh-keygen.c ssh-keyscan.c ssh.c ssh.h ssh1.h sshconnect1.c sshd.c ttymodes.c] move ssh1 definitions to ssh1.h, pathnames to pathnames.h - markus@cvs.openbsd.org 2001/01/19 16:48:14 [sshd.8] fix typo; from stevesk@ - markus@cvs.openbsd.org 2001/01/19 16:50:58 [ssh-dss.c] clear and free digest, make consistent with other code (use dlen); from stevesk@ - markus@cvs.openbsd.org 2001/01/20 15:55:20 GMT 2001 by markus [auth-options.c auth-options.h auth-rsa.c auth2.c] pass the filename to auth_parse_options() - markus@cvs.openbsd.org 2001/01/20 17:59:40 GMT 2001 [readconf.c] fix SIGSEGV from -o ""; problem noted by jehsom@togetherweb.com - stevesk@cvs.openbsd.org 2001/01/20 18:20:29 [sshconnect2.c] dh_new_group() does not return NULL. ok markus@ - markus@cvs.openbsd.org 2001/01/20 21:33:42 [ssh-add.c] do not loop forever if askpass does not exist; from andrew@pimlott.ne.mediaone.net - djm@cvs.openbsd.org 2001/01/20 23:00:56 [servconf.c] Check for NULL return from strdelim; ok markus - djm@cvs.openbsd.org 2001/01/20 23:02:07 [readconf.c] KNF; ok markus - jakob@cvs.openbsd.org 2001/01/21 9:00:33 [ssh-keygen.1] remove -R flag; ok markus@ - markus@cvs.openbsd.org 2001/01/21 19:05:40 [atomicio.c automicio.h auth-chall.c auth-krb4.c auth-options.c auth-options.h auth-passwd.c auth-rh-rsa.c auth-rhosts.c auth-rsa.c auth.c auth.h auth1.c auth2-chall.c auth2.c authfd.c authfile.c bufaux.c bufaux.h buffer.c canahost.c canahost.h channels.c cipher.c cli.c clientloop.c clientloop.h compat.c compress.c deattack.c dh.c dispatch.c groupaccess.c hmac.c hostfile.c kex.c key.c key.h log-client.c log-server.c log.c log.h login.c login.h match.c misc.c misc.h nchan.c packet.c pty.c radix.h readconf.c readpass.c readpass.h rsa.c scp.c servconf.c serverloop.c serverloop.h session.c sftp-server.c ssh-add.c ssh-agent.c ssh-dss.c ssh-keygen.c ssh-keyscan.c ssh-rsa.c ssh.c ssh.h sshconnect.c sshconnect.h sshconnect1.c sshconnect2.c sshd.c tildexpand.c tildexpand.h ttysmodes.c uidswap.c xmalloc.c] split ssh.h and try to cleanup the #include mess. remove unnecessary #includes. rename util.[ch] -> misc.[ch] - (bal) renamed 'PIDDIR' to '_PATH_SSH_PIDDIR' to match OpenBSD tree - (bal) Moved #ifdef KRB4 in auth-krb4.c above the #include to resolve conflict when compiling for non-kerb install - (bal) removed the #ifdef SKEY in auth1.c to match Markus' changes on 1/19.
2001-01-22 05:34:40 +00:00
#include "log.h"
#include "readconf.h"
#include "atomicio.h"
#include "misc.h"
#include "dns.h"
#include "version.h"
char *client_version_string = NULL;
char *server_version_string = NULL;
static int matching_host_key_dns = 0;
/* import */
extern Options options;
extern char *__progname;
extern uid_t original_real_uid;
extern uid_t original_effective_uid;
extern pid_t proxy_command_pid;
#ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */
#define INET6_ADDRSTRLEN 46
#endif
static int show_other_keys(const char *, Key *);
static void warn_changed_key(Key *);
static void
ms_subtract_diff(struct timeval *start, int *ms)
{
struct timeval diff, finish;
gettimeofday(&finish, NULL);
timersub(&finish, start, &diff);
*ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
}
static void
ms_to_timeval(struct timeval *tv, int ms)
{
tv->tv_sec = ms / 1000;
tv->tv_usec = (ms % 1000) * 1000;
}
/*
* Connect to the given ssh server using a proxy command.
*/
static int
ssh_proxy_connect(const char *host, u_short port, const char *proxy_command)
1999-10-27 03:42:43 +00:00
{
char *command_string, *tmp;
int pin[2], pout[2];
pid_t pid;
char *shell, strport[NI_MAXSERV];
if ((shell = getenv("SHELL")) == NULL)
shell = _PATH_BSHELL;
/* Convert the port number into a string. */
snprintf(strport, sizeof strport, "%hu", port);
/*
* Build the final command string in the buffer by making the
* appropriate substitutions to the given proxy command.
*
* Use "exec" to avoid "sh -c" processes on some platforms
* (e.g. Solaris)
*/
xasprintf(&tmp, "exec %s", proxy_command);
command_string = percent_expand(tmp, "h", host,
"p", strport, (char *)NULL);
xfree(tmp);
/* Create pipes for communicating with the proxy. */
if (pipe(pin) < 0 || pipe(pout) < 0)
fatal("Could not create pipes to communicate with the proxy: %.100s",
strerror(errno));
debug("Executing proxy command: %.500s", command_string);
/* Fork and execute the proxy command. */
if ((pid = fork()) == 0) {
char *argv[10];
/* Child. Permanently give up superuser privileges. */
permanently_drop_suid(original_real_uid);
/* Redirect stdin and stdout. */
close(pin[1]);
if (pin[0] != 0) {
if (dup2(pin[0], 0) < 0)
perror("dup2 stdin");
close(pin[0]);
}
close(pout[0]);
if (dup2(pout[1], 1) < 0)
perror("dup2 stdout");
/* Cannot be 1 because pin allocated two descriptors. */
close(pout[1]);
/* Stderr is left as it is so that error messages get
printed on the user's terminal. */
argv[0] = shell;
argv[1] = "-c";
argv[2] = command_string;
argv[3] = NULL;
/* Execute the proxy command. Note that we gave up any
extra privileges above. */
2001-01-07 11:45:22 +00:00
execv(argv[0], argv);
perror(argv[0]);
exit(1);
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}
/* Parent. */
if (pid < 0)
fatal("fork failed: %.100s", strerror(errno));
else
proxy_command_pid = pid; /* save pid to clean up later */
/* Close child side of the descriptors. */
close(pin[0]);
close(pout[1]);
/* Free the command name. */
xfree(command_string);
/* Set the connection file descriptors. */
packet_set_connection(pout[0], pin[1]);
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/* Indicate OK return */
return 0;
}
1999-10-27 03:42:43 +00:00
/*
* Creates a (possibly privileged) socket for use as the ssh connection.
*/
static int
ssh_create_socket(int privileged, struct addrinfo *ai)
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{
int sock, gaierr;
struct addrinfo hints, *res;
/*
* If we are running as root and want to connect to a privileged
* port, bind our own socket to a privileged port.
*/
if (privileged) {
int p = IPPORT_RESERVED - 1;
PRIV_START;
sock = rresvport_af(&p, ai->ai_family);
PRIV_END;
if (sock < 0)
error("rresvport: af=%d %.100s", ai->ai_family,
strerror(errno));
- OpenBSD CVS updates to v1.2.3 [ssh.h atomicio.c] - int atomicio -> ssize_t (for alpha). ok deraadt@ [auth-rsa.c] - delay MD5 computation until client sends response, free() early, cleanup. [cipher.c] - void* -> unsigned char*, ok niels@ [hostfile.c] - remove unused variable 'len'. fix comments. - remove unused variable [log-client.c log-server.c] - rename a cpp symbol, to avoid param.h collision [packet.c] - missing xfree() - getsockname() requires initialized tolen; andy@guildsoftware.com - use getpeername() in packet_connection_is_on_socket(), fixes sshd -i; from Holger.Trapp@Informatik.TU-Chemnitz.DE [pty.c pty.h] - register cleanup for pty earlier. move code for pty-owner handling to pty.c ok provos@, dugsong@ [readconf.c] - turn off x11-fwd for the client, too. [rsa.c] - PKCS#1 padding [scp.c] - allow '.' in usernames; from jedgar@fxp.org [servconf.c] - typo: ignore_user_known_hosts int->flag; naddy@mips.rhein-neckar.de - sync with sshd_config [ssh-keygen.c] - enable ssh-keygen -l -f ~/.ssh/known_hosts, ok deraadt@ [ssh.1] - Change invalid 'CHAT' loglevel to 'VERBOSE' [ssh.c] - suppress AAAA query host when '-4' is used; from shin@nd.net.fujitsu.co.jp - turn off x11-fwd for the client, too. [sshconnect.c] - missing xfree() - retry rresvport_af(), too. from sumikawa@ebina.hitachi.co.jp. - read error vs. "Connection closed by remote host" [sshd.8] - ie. -> i.e., - do not link to a commercial page.. - sync with sshd_config [sshd.c] - no need for poll.h; from bright@wintelcom.net - log with level log() not fatal() if peer behaves badly. - don't panic if client behaves strange. ok deraadt@ - make no-port-forwarding for RSA keys deny both -L and -R style fwding - delay close() of pty until the pty has been chowned back to root - oops, fix comment, too. - missing xfree() - move XAUTHORITY to subdir. ok dugsong@. fixes debian bug #57907, too. (http://cgi.debian.org/cgi-bin/bugreport.cgi?archive=no&bug=57907) - register cleanup for pty earlier. move code for pty-owner handling to pty.c ok provos@, dugsong@ - create x11 cookie file - fix pr 1113, fclose() -> pclose(), todo: remote popen() - version 1.2.3 - Cleaned up
2000-03-09 10:27:49 +00:00
else
debug("Allocated local port %d.", p);
return sock;
}
sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (sock < 0)
error("socket: %.100s", strerror(errno));
/* Bind the socket to an alternative local IP address */
if (options.bind_address == NULL)
return sock;
memset(&hints, 0, sizeof(hints));
hints.ai_family = ai->ai_family;
hints.ai_socktype = ai->ai_socktype;
hints.ai_protocol = ai->ai_protocol;
hints.ai_flags = AI_PASSIVE;
gaierr = getaddrinfo(options.bind_address, "0", &hints, &res);
if (gaierr) {
error("getaddrinfo: %s: %s", options.bind_address,
ssh_gai_strerror(gaierr));
close(sock);
return -1;
}
if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
error("bind: %s: %s", options.bind_address, strerror(errno));
close(sock);
freeaddrinfo(res);
return -1;
}
freeaddrinfo(res);
return sock;
1999-10-27 03:42:43 +00:00
}
static int
timeout_connect(int sockfd, const struct sockaddr *serv_addr,
socklen_t addrlen, int *timeoutp)
{
fd_set *fdset;
struct timeval tv, t_start;
socklen_t optlen;
int optval, rc, result = -1;
gettimeofday(&t_start, NULL);
if (*timeoutp <= 0) {
result = connect(sockfd, serv_addr, addrlen);
goto done;
}
set_nonblock(sockfd);
rc = connect(sockfd, serv_addr, addrlen);
if (rc == 0) {
unset_nonblock(sockfd);
result = 0;
goto done;
}
if (errno != EINPROGRESS) {
result = -1;
goto done;
}
fdset = (fd_set *)xcalloc(howmany(sockfd + 1, NFDBITS),
sizeof(fd_mask));
FD_SET(sockfd, fdset);
ms_to_timeval(&tv, *timeoutp);
for (;;) {
rc = select(sockfd + 1, NULL, fdset, NULL, &tv);
if (rc != -1 || errno != EINTR)
break;
}
switch (rc) {
case 0:
/* Timed out */
errno = ETIMEDOUT;
break;
case -1:
/* Select error */
debug("select: %s", strerror(errno));
break;
case 1:
/* Completed or failed */
optval = 0;
optlen = sizeof(optval);
if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval,
&optlen) == -1) {
debug("getsockopt: %s", strerror(errno));
break;
}
if (optval != 0) {
errno = optval;
break;
}
result = 0;
unset_nonblock(sockfd);
break;
default:
/* Should not occur */
fatal("Bogus return (%d) from select()", rc);
}
xfree(fdset);
done:
if (result == 0 && *timeoutp > 0) {
ms_subtract_diff(&t_start, timeoutp);
if (*timeoutp <= 0) {
errno = ETIMEDOUT;
result = -1;
}
}
return (result);
}
/*
* Opens a TCP/IP connection to the remote server on the given host.
* The address of the remote host will be returned in hostaddr.
* If port is 0, the default port will be used. If needpriv is true,
* a privileged port will be allocated to make the connection.
* This requires super-user privileges if needpriv is true.
* Connection_attempts specifies the maximum number of tries (one per
* second). If proxy_command is non-NULL, it specifies the command (with %h
* and %p substituted for host and port, respectively) to use to contact
* the daemon.
*/
int
ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
u_short port, int family, int connection_attempts, int *timeout_ms,
int want_keepalive, int needpriv, const char *proxy_command)
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{
NOTE: This update changes the RSA key generation. *NEW RSA KEYS NEED TO BE GENERATED* =) Refer to to entry "2001/01/16 19:20:06" for more details. 20010118 - (bal) Super Sized OpenBSD Resync - markus@cvs.openbsd.org 2001/01/11 22:14:20 GMT 2001 by markus [sshd.c] maxfd+1 - markus@cvs.openbsd.org 2001/01/13 17:59:18 [ssh-keygen.1] small ssh-keygen manpage cleanup; stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:03:07 [scp.c ssh-keygen.c sshd.c] getopt() returns -1 not EOF; stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:06:54 [ssh-keyscan.c] use SSH_DEFAULT_PORT; from stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:12:47 [ssh-keyscan.c] free() -> xfree(); fix memory leak; from stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:14:13 [ssh-add.c] typo, from stevesk@sweden.hp.com - markus@cvs.openbsd.org 2001/01/13 18:32:50 [packet.c session.c ssh.c sshconnect.c sshd.c] split out keepalive from packet_interactive (from dale@accentre.com) set IPTOS_LOWDELAY TCP_NODELAY IPTOS_THROUGHPUT for ssh2, too. - markus@cvs.openbsd.org 2001/01/13 18:36:45 [packet.c packet.h] reorder, typo - markus@cvs.openbsd.org 2001/01/13 18:38:00 [auth-options.c] fix comment - markus@cvs.openbsd.org 2001/01/13 18:43:31 [session.c] Wall - markus@cvs.openbsd.org 2001/01/13 19:14:08 [clientloop.h clientloop.c ssh.c] move callback to headerfile - markus@cvs.openbsd.org 2001/01/15 21:40:10 [ssh.c] use log() instead of stderr - markus@cvs.openbsd.org 2001/01/15 21:43:51 [dh.c] use error() not stderr! - markus@cvs.openbsd.org 2001/01/15 21:45:29 [sftp-server.c] rename must fail if newpath exists, debug off by default - markus@cvs.openbsd.org 2001/01/15 21:46:38 [sftp-server.c] readable long listing for sftp-server, ok deraadt@ - markus@cvs.openbsd.org 2001/01/16 19:20:06 [key.c ssh-rsa.c] make "ssh-rsa" key format for ssh2 confirm to the ietf-drafts; from galb@vandyke.com. note that you have to delete older ssh2-rsa keys, since they are in the wrong format, too. they must be removed from .ssh/authorized_keys2 and .ssh/known_hosts2, etc. (cd; grep -v ssh-rsa .ssh/authorized_keys2 > TMP && mv TMP .ssh/authorized_keys2) additionally, we now check that BN_num_bits(rsa->n) >= 768. - markus@cvs.openbsd.org 2001/01/16 20:54:27 [sftp-server.c] remove some statics. simpler handles; idea from nisse@lysator.liu.se - deraadt@cvs.openbsd.org 2001/01/16 23:58:08 [bufaux.c radix.c sshconnect.h sshconnect1.c] indent - (bal) Added bsd-strmode.[ch] since some non-OpenBSD platforms may be missing such feature.
2001-01-18 02:04:35 +00:00
int gaierr;
int on = 1;
int sock = -1, attempt;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
NOTE: This update changes the RSA key generation. *NEW RSA KEYS NEED TO BE GENERATED* =) Refer to to entry "2001/01/16 19:20:06" for more details. 20010118 - (bal) Super Sized OpenBSD Resync - markus@cvs.openbsd.org 2001/01/11 22:14:20 GMT 2001 by markus [sshd.c] maxfd+1 - markus@cvs.openbsd.org 2001/01/13 17:59:18 [ssh-keygen.1] small ssh-keygen manpage cleanup; stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:03:07 [scp.c ssh-keygen.c sshd.c] getopt() returns -1 not EOF; stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:06:54 [ssh-keyscan.c] use SSH_DEFAULT_PORT; from stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:12:47 [ssh-keyscan.c] free() -> xfree(); fix memory leak; from stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:14:13 [ssh-add.c] typo, from stevesk@sweden.hp.com - markus@cvs.openbsd.org 2001/01/13 18:32:50 [packet.c session.c ssh.c sshconnect.c sshd.c] split out keepalive from packet_interactive (from dale@accentre.com) set IPTOS_LOWDELAY TCP_NODELAY IPTOS_THROUGHPUT for ssh2, too. - markus@cvs.openbsd.org 2001/01/13 18:36:45 [packet.c packet.h] reorder, typo - markus@cvs.openbsd.org 2001/01/13 18:38:00 [auth-options.c] fix comment - markus@cvs.openbsd.org 2001/01/13 18:43:31 [session.c] Wall - markus@cvs.openbsd.org 2001/01/13 19:14:08 [clientloop.h clientloop.c ssh.c] move callback to headerfile - markus@cvs.openbsd.org 2001/01/15 21:40:10 [ssh.c] use log() instead of stderr - markus@cvs.openbsd.org 2001/01/15 21:43:51 [dh.c] use error() not stderr! - markus@cvs.openbsd.org 2001/01/15 21:45:29 [sftp-server.c] rename must fail if newpath exists, debug off by default - markus@cvs.openbsd.org 2001/01/15 21:46:38 [sftp-server.c] readable long listing for sftp-server, ok deraadt@ - markus@cvs.openbsd.org 2001/01/16 19:20:06 [key.c ssh-rsa.c] make "ssh-rsa" key format for ssh2 confirm to the ietf-drafts; from galb@vandyke.com. note that you have to delete older ssh2-rsa keys, since they are in the wrong format, too. they must be removed from .ssh/authorized_keys2 and .ssh/known_hosts2, etc. (cd; grep -v ssh-rsa .ssh/authorized_keys2 > TMP && mv TMP .ssh/authorized_keys2) additionally, we now check that BN_num_bits(rsa->n) >= 768. - markus@cvs.openbsd.org 2001/01/16 20:54:27 [sftp-server.c] remove some statics. simpler handles; idea from nisse@lysator.liu.se - deraadt@cvs.openbsd.org 2001/01/16 23:58:08 [bufaux.c radix.c sshconnect.h sshconnect1.c] indent - (bal) Added bsd-strmode.[ch] since some non-OpenBSD platforms may be missing such feature.
2001-01-18 02:04:35 +00:00
struct addrinfo hints, *ai, *aitop;
debug2("ssh_connect: needpriv %d", needpriv);
/* If a proxy command is given, connect using it. */
if (proxy_command != NULL)
return ssh_proxy_connect(host, port, proxy_command);
/* No proxy command. */
memset(&hints, 0, sizeof(hints));
hints.ai_family = family;
hints.ai_socktype = SOCK_STREAM;
snprintf(strport, sizeof strport, "%u", port);
if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
fatal("%s: Could not resolve hostname %.100s: %s", __progname,
host, ssh_gai_strerror(gaierr));
for (attempt = 0; attempt < connection_attempts; attempt++) {
if (attempt > 0) {
/* Sleep a moment before retrying. */
sleep(1);
debug("Trying again...");
}
/*
* Loop through addresses for this host, and try each one in
* sequence until the connection succeeds.
*/
for (ai = aitop; ai; ai = ai->ai_next) {
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
continue;
if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
ntop, sizeof(ntop), strport, sizeof(strport),
NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
error("ssh_connect: getnameinfo failed");
continue;
}
debug("Connecting to %.200s [%.100s] port %s.",
host, ntop, strport);
/* Create a socket for connecting. */
sock = ssh_create_socket(needpriv, ai);
if (sock < 0)
/* Any error is already output */
continue;
if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen,
timeout_ms) >= 0) {
/* Successful connection. */
memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
break;
} else {
debug("connect to address %s port %s: %s",
ntop, strport, strerror(errno));
close(sock);
sock = -1;
}
1999-10-27 03:42:43 +00:00
}
if (sock != -1)
break; /* Successful connection. */
}
freeaddrinfo(aitop);
/* Return failure if we didn't get a successful connection. */
if (sock == -1) {
error("ssh: connect to host %s port %s: %s",
host, strport, strerror(errno));
return (-1);
}
1999-10-27 03:42:43 +00:00
debug("Connection established.");
1999-10-27 03:42:43 +00:00
/* Set SO_KEEPALIVE if requested. */
if (want_keepalive &&
NOTE: This update changes the RSA key generation. *NEW RSA KEYS NEED TO BE GENERATED* =) Refer to to entry "2001/01/16 19:20:06" for more details. 20010118 - (bal) Super Sized OpenBSD Resync - markus@cvs.openbsd.org 2001/01/11 22:14:20 GMT 2001 by markus [sshd.c] maxfd+1 - markus@cvs.openbsd.org 2001/01/13 17:59:18 [ssh-keygen.1] small ssh-keygen manpage cleanup; stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:03:07 [scp.c ssh-keygen.c sshd.c] getopt() returns -1 not EOF; stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:06:54 [ssh-keyscan.c] use SSH_DEFAULT_PORT; from stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:12:47 [ssh-keyscan.c] free() -> xfree(); fix memory leak; from stevesk@pobox.com - markus@cvs.openbsd.org 2001/01/13 18:14:13 [ssh-add.c] typo, from stevesk@sweden.hp.com - markus@cvs.openbsd.org 2001/01/13 18:32:50 [packet.c session.c ssh.c sshconnect.c sshd.c] split out keepalive from packet_interactive (from dale@accentre.com) set IPTOS_LOWDELAY TCP_NODELAY IPTOS_THROUGHPUT for ssh2, too. - markus@cvs.openbsd.org 2001/01/13 18:36:45 [packet.c packet.h] reorder, typo - markus@cvs.openbsd.org 2001/01/13 18:38:00 [auth-options.c] fix comment - markus@cvs.openbsd.org 2001/01/13 18:43:31 [session.c] Wall - markus@cvs.openbsd.org 2001/01/13 19:14:08 [clientloop.h clientloop.c ssh.c] move callback to headerfile - markus@cvs.openbsd.org 2001/01/15 21:40:10 [ssh.c] use log() instead of stderr - markus@cvs.openbsd.org 2001/01/15 21:43:51 [dh.c] use error() not stderr! - markus@cvs.openbsd.org 2001/01/15 21:45:29 [sftp-server.c] rename must fail if newpath exists, debug off by default - markus@cvs.openbsd.org 2001/01/15 21:46:38 [sftp-server.c] readable long listing for sftp-server, ok deraadt@ - markus@cvs.openbsd.org 2001/01/16 19:20:06 [key.c ssh-rsa.c] make "ssh-rsa" key format for ssh2 confirm to the ietf-drafts; from galb@vandyke.com. note that you have to delete older ssh2-rsa keys, since they are in the wrong format, too. they must be removed from .ssh/authorized_keys2 and .ssh/known_hosts2, etc. (cd; grep -v ssh-rsa .ssh/authorized_keys2 > TMP && mv TMP .ssh/authorized_keys2) additionally, we now check that BN_num_bits(rsa->n) >= 768. - markus@cvs.openbsd.org 2001/01/16 20:54:27 [sftp-server.c] remove some statics. simpler handles; idea from nisse@lysator.liu.se - deraadt@cvs.openbsd.org 2001/01/16 23:58:08 [bufaux.c radix.c sshconnect.h sshconnect1.c] indent - (bal) Added bsd-strmode.[ch] since some non-OpenBSD platforms may be missing such feature.
2001-01-18 02:04:35 +00:00
setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
sizeof(on)) < 0)
error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
1999-10-27 03:42:43 +00:00
/* Set the connection. */
packet_set_connection(sock, sock);
1999-10-27 03:42:43 +00:00
return 0;
1999-10-27 03:42:43 +00:00
}
/*
* Waits for the server identification string, and sends our own
* identification string.
*/
static void
ssh_exchange_identification(int timeout_ms)
1999-10-27 03:42:43 +00:00
{
char buf[256], remote_version[256]; /* must be same size! */
int remote_major, remote_minor, mismatch;
int connection_in = packet_get_connection_in();
int connection_out = packet_get_connection_out();
int minor1 = PROTOCOL_MINOR_1;
u_int i, n;
size_t len;
int fdsetsz, remaining, rc;
struct timeval t_start, t_remaining;
fd_set *fdset;
fdsetsz = howmany(connection_in + 1, NFDBITS) * sizeof(fd_mask);
fdset = xcalloc(1, fdsetsz);
/* Read other side's version identification. */
remaining = timeout_ms;
for (n = 0;;) {
for (i = 0; i < sizeof(buf) - 1; i++) {
if (timeout_ms > 0) {
gettimeofday(&t_start, NULL);
ms_to_timeval(&t_remaining, remaining);
FD_SET(connection_in, fdset);
rc = select(connection_in + 1, fdset, NULL,
fdset, &t_remaining);
ms_subtract_diff(&t_start, &remaining);
if (rc == 0 || remaining <= 0)
fatal("Connection timed out during "
"banner exchange");
if (rc == -1) {
if (errno == EINTR)
continue;
fatal("ssh_exchange_identification: "
"select: %s", strerror(errno));
}
}
len = atomicio(read, connection_in, &buf[i], 1);
if (len != 1 && errno == EPIPE)
fatal("ssh_exchange_identification: "
"Connection closed by remote host");
else if (len != 1)
fatal("ssh_exchange_identification: "
"read: %.100s", strerror(errno));
if (buf[i] == '\r') {
buf[i] = '\n';
buf[i + 1] = 0;
continue; /**XXX wait for \n */
}
if (buf[i] == '\n') {
buf[i + 1] = 0;
break;
}
if (++n > 65536)
fatal("ssh_exchange_identification: "
"No banner received");
}
buf[sizeof(buf) - 1] = 0;
if (strncmp(buf, "SSH-", 4) == 0)
break;
debug("ssh_exchange_identification: %s", buf);
1999-10-27 03:42:43 +00:00
}
server_version_string = xstrdup(buf);
xfree(fdset);
/*
* Check that the versions match. In future this might accept
* several versions and set appropriate flags to handle them.
*/
if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
&remote_major, &remote_minor, remote_version) != 3)
fatal("Bad remote protocol version identification: '%.100s'", buf);
debug("Remote protocol version %d.%d, remote software version %.100s",
remote_major, remote_minor, remote_version);
compat_datafellows(remote_version);
mismatch = 0;
switch (remote_major) {
case 1:
if (remote_minor == 99 &&
(options.protocol & SSH_PROTO_2) &&
!(options.protocol & SSH_PROTO_1_PREFERRED)) {
enable_compat20();
break;
}
if (!(options.protocol & SSH_PROTO_1)) {
mismatch = 1;
break;
}
if (remote_minor < 3) {
fatal("Remote machine has too old SSH software version.");
- (djm) Merge OpenBSD changes: - markus@cvs.openbsd.org 2000/11/06 16:04:56 [channels.c channels.h clientloop.c nchan.c serverloop.c] [session.c ssh.c] agent forwarding and -R for ssh2, based on work from jhuuskon@messi.uku.fi - markus@cvs.openbsd.org 2000/11/06 16:13:27 [ssh.c sshconnect.c sshd.c] do not disabled rhosts(rsa) if server port > 1024; from pekkas@netcore.fi - markus@cvs.openbsd.org 2000/11/06 16:16:35 [sshconnect.c] downgrade client to 1.3 if server is 1.4; help from mdb@juniper.net - markus@cvs.openbsd.org 2000/11/09 18:04:40 [auth1.c] typo; from mouring@pconline.com - markus@cvs.openbsd.org 2000/11/12 12:03:28 [ssh-agent.c] off-by-one when removing a key from the agent - markus@cvs.openbsd.org 2000/11/12 12:50:39 [auth-rh-rsa.c auth2.c authfd.c authfd.h] [authfile.c hostfile.c kex.c kex.h key.c key.h myproposal.h] [readconf.c readconf.h rsa.c rsa.h servconf.c servconf.h ssh-add.c] [ssh-agent.c ssh-keygen.1 ssh-keygen.c ssh.1 ssh.c ssh_config] [sshconnect1.c sshconnect2.c sshd.8 sshd.c sshd_config ssh-dss.c] [ssh-dss.h ssh-rsa.c ssh-rsa.h dsa.c dsa.h] add support for RSA to SSH2. please test. there are now 3 types of keys: RSA1 is used by ssh-1 only, RSA and DSA are used by SSH2. you can use 'ssh-keygen -t rsa -f ssh2_rsa_file' to generate RSA keys for SSH2 and use the RSA keys for hostkeys or for user keys. SSH2 RSA or DSA keys are added to .ssh/authorised_keys2 as before. - (djm) Fix up Makefile and Redhat init script to create RSA host keys - (djm) Change to interim version
2000-11-13 11:57:25 +00:00
} else if (remote_minor == 3 || remote_minor == 4) {
/* We speak 1.3, too. */
enable_compat13();
- (djm) Merge OpenBSD changes: - markus@cvs.openbsd.org 2000/11/06 16:04:56 [channels.c channels.h clientloop.c nchan.c serverloop.c] [session.c ssh.c] agent forwarding and -R for ssh2, based on work from jhuuskon@messi.uku.fi - markus@cvs.openbsd.org 2000/11/06 16:13:27 [ssh.c sshconnect.c sshd.c] do not disabled rhosts(rsa) if server port > 1024; from pekkas@netcore.fi - markus@cvs.openbsd.org 2000/11/06 16:16:35 [sshconnect.c] downgrade client to 1.3 if server is 1.4; help from mdb@juniper.net - markus@cvs.openbsd.org 2000/11/09 18:04:40 [auth1.c] typo; from mouring@pconline.com - markus@cvs.openbsd.org 2000/11/12 12:03:28 [ssh-agent.c] off-by-one when removing a key from the agent - markus@cvs.openbsd.org 2000/11/12 12:50:39 [auth-rh-rsa.c auth2.c authfd.c authfd.h] [authfile.c hostfile.c kex.c kex.h key.c key.h myproposal.h] [readconf.c readconf.h rsa.c rsa.h servconf.c servconf.h ssh-add.c] [ssh-agent.c ssh-keygen.1 ssh-keygen.c ssh.1 ssh.c ssh_config] [sshconnect1.c sshconnect2.c sshd.8 sshd.c sshd_config ssh-dss.c] [ssh-dss.h ssh-rsa.c ssh-rsa.h dsa.c dsa.h] add support for RSA to SSH2. please test. there are now 3 types of keys: RSA1 is used by ssh-1 only, RSA and DSA are used by SSH2. you can use 'ssh-keygen -t rsa -f ssh2_rsa_file' to generate RSA keys for SSH2 and use the RSA keys for hostkeys or for user keys. SSH2 RSA or DSA keys are added to .ssh/authorised_keys2 as before. - (djm) Fix up Makefile and Redhat init script to create RSA host keys - (djm) Change to interim version
2000-11-13 11:57:25 +00:00
minor1 = 3;
if (options.forward_agent) {
2003-04-09 10:59:48 +00:00
logit("Agent forwarding disabled for protocol 1.3");
options.forward_agent = 0;
}
}
break;
case 2:
if (options.protocol & SSH_PROTO_2) {
enable_compat20();
break;
}
/* FALLTHROUGH */
default:
mismatch = 1;
break;
1999-10-27 03:42:43 +00:00
}
if (mismatch)
fatal("Protocol major versions differ: %d vs. %d",
(options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
remote_major);
/* Send our own protocol version identification. */
snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
- (djm) Merge OpenBSD changes: - markus@cvs.openbsd.org 2000/11/06 16:04:56 [channels.c channels.h clientloop.c nchan.c serverloop.c] [session.c ssh.c] agent forwarding and -R for ssh2, based on work from jhuuskon@messi.uku.fi - markus@cvs.openbsd.org 2000/11/06 16:13:27 [ssh.c sshconnect.c sshd.c] do not disabled rhosts(rsa) if server port > 1024; from pekkas@netcore.fi - markus@cvs.openbsd.org 2000/11/06 16:16:35 [sshconnect.c] downgrade client to 1.3 if server is 1.4; help from mdb@juniper.net - markus@cvs.openbsd.org 2000/11/09 18:04:40 [auth1.c] typo; from mouring@pconline.com - markus@cvs.openbsd.org 2000/11/12 12:03:28 [ssh-agent.c] off-by-one when removing a key from the agent - markus@cvs.openbsd.org 2000/11/12 12:50:39 [auth-rh-rsa.c auth2.c authfd.c authfd.h] [authfile.c hostfile.c kex.c kex.h key.c key.h myproposal.h] [readconf.c readconf.h rsa.c rsa.h servconf.c servconf.h ssh-add.c] [ssh-agent.c ssh-keygen.1 ssh-keygen.c ssh.1 ssh.c ssh_config] [sshconnect1.c sshconnect2.c sshd.8 sshd.c sshd_config ssh-dss.c] [ssh-dss.h ssh-rsa.c ssh-rsa.h dsa.c dsa.h] add support for RSA to SSH2. please test. there are now 3 types of keys: RSA1 is used by ssh-1 only, RSA and DSA are used by SSH2. you can use 'ssh-keygen -t rsa -f ssh2_rsa_file' to generate RSA keys for SSH2 and use the RSA keys for hostkeys or for user keys. SSH2 RSA or DSA keys are added to .ssh/authorised_keys2 as before. - (djm) Fix up Makefile and Redhat init script to create RSA host keys - (djm) Change to interim version
2000-11-13 11:57:25 +00:00
compat20 ? PROTOCOL_MINOR_2 : minor1,
SSH_VERSION);
if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf))
fatal("write: %.100s", strerror(errno));
client_version_string = xstrdup(buf);
chop(client_version_string);
chop(server_version_string);
debug("Local version string %.100s", client_version_string);
1999-10-27 03:42:43 +00:00
}
/* defaults to 'no' */
static int
confirm(const char *prompt)
1999-10-27 03:42:43 +00:00
{
const char *msg, *again = "Please type 'yes' or 'no': ";
char *p;
int ret = -1;
if (options.batch_mode)
return 0;
for (msg = prompt;;msg = again) {
p = read_passphrase(msg, RP_ECHO);
if (p == NULL ||
(p[0] == '\0') || (p[0] == '\n') ||
strncasecmp(p, "no", 2) == 0)
ret = 0;
if (p && strncasecmp(p, "yes", 3) == 0)
ret = 1;
if (p)
xfree(p);
if (ret != -1)
return ret;
1999-10-27 03:42:43 +00:00
}
}
/*
* check whether the supplied host key is valid, return -1 if the key
* is not valid. the user_hostfile will not be updated if 'readonly' is true.
*/
#define RDRW 0
#define RDONLY 1
#define ROQUIET 2
static int
check_host_key(char *hostname, struct sockaddr *hostaddr, u_short port,
Key *host_key, int readonly, const char *user_hostfile,
const char *system_hostfile)
1999-10-27 03:42:43 +00:00
{
Key *file_key;
const char *type = key_type(host_key);
char *ip = NULL, *host = NULL;
char hostline[1000], *hostp, *fp;
HostStatus host_status;
HostStatus ip_status;
int r, local = 0, host_ip_differ = 0;
int salen;
char ntop[NI_MAXHOST];
char msg[1024];
int len, host_line, ip_line;
const char *host_file = NULL, *ip_file = NULL;
/*
* Force accepting of the host key for loopback/localhost. The
* problem is that if the home directory is NFS-mounted to multiple
* machines, localhost will refer to a different machine in each of
* them, and the user will get bogus HOST_CHANGED warnings. This
* essentially disables host authentication for localhost; however,
* this is probably not a real problem.
*/
/** hostaddr == 0! */
switch (hostaddr->sa_family) {
case AF_INET:
local = (ntohl(((struct sockaddr_in *)hostaddr)->
sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
salen = sizeof(struct sockaddr_in);
break;
case AF_INET6:
local = IN6_IS_ADDR_LOOPBACK(
&(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
salen = sizeof(struct sockaddr_in6);
break;
default:
local = 0;
salen = sizeof(struct sockaddr_storage);
break;
}
if (options.no_host_authentication_for_localhost == 1 && local &&
options.host_key_alias == NULL) {
debug("Forcing accepting of host key for "
"loopback/localhost.");
return 0;
}
/*
* We don't have the remote ip-address for connections
* using a proxy command
*/
if (options.proxy_command == NULL) {
if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop),
NULL, 0, NI_NUMERICHOST) != 0)
fatal("check_host_key: getnameinfo failed");
ip = put_host_port(ntop, port);
} else {
ip = xstrdup("<no hostip for proxy command>");
}
/*
* Turn off check_host_ip if the connection is to localhost, via proxy
* command or if we don't have a hostname to compare with
*/
if (options.check_host_ip && (local ||
strcmp(hostname, ip) == 0 || options.proxy_command != NULL))
options.check_host_ip = 0;
/*
* Allow the user to record the key under a different name or
* differentiate a non-standard port. This is useful for ssh
* tunneling over forwarded connections or if you run multiple
* sshd's on different ports on the same machine.
*/
if (options.host_key_alias != NULL) {
host = xstrdup(options.host_key_alias);
debug("using hostkeyalias: %s", host);
} else {
host = put_host_port(hostname, port);
}
/*
* Store the host key from the known host file in here so that we can
* compare it with the key for the IP address.
*/
file_key = key_new(host_key->type);
/*
* Check if the host key is present in the user's list of known
* hosts or in the systemwide list.
*/
host_file = user_hostfile;
host_status = check_host_in_hostfile(host_file, host, host_key,
file_key, &host_line);
if (host_status == HOST_NEW) {
host_file = system_hostfile;
host_status = check_host_in_hostfile(host_file, host, host_key,
file_key, &host_line);
}
/*
* Also perform check for the ip address, skip the check if we are
* localhost or the hostname was an ip address to begin with
*/
if (options.check_host_ip) {
Key *ip_key = key_new(host_key->type);
ip_file = user_hostfile;
ip_status = check_host_in_hostfile(ip_file, ip, host_key,
ip_key, &ip_line);
if (ip_status == HOST_NEW) {
ip_file = system_hostfile;
ip_status = check_host_in_hostfile(ip_file, ip,
host_key, ip_key, &ip_line);
}
if (host_status == HOST_CHANGED &&
(ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
host_ip_differ = 1;
key_free(ip_key);
} else
ip_status = host_status;
key_free(file_key);
switch (host_status) {
case HOST_OK:
/* The host is known and the key matches. */
- Remove references to SSLeay. - Big OpenBSD CVS update - markus@cvs.openbsd.org [clientloop.c] - typo [session.c] - update proctitle on pty alloc/dealloc, e.g. w/ windows client [session.c] - update proctitle for proto 1, too [channels.h nchan.c serverloop.c session.c sshd.c] - use c-style comments - deraadt@cvs.openbsd.org [scp.c] - more atomicio - markus@cvs.openbsd.org [channels.c] - set O_NONBLOCK [ssh.1] - update AUTHOR [readconf.c ssh-keygen.c ssh.h] - default DSA key file ~/.ssh/id_dsa [clientloop.c] - typo, rm verbose debug - deraadt@cvs.openbsd.org [ssh-keygen.1] - document DSA use of ssh-keygen [sshd.8] - a start at describing what i understand of the DSA side [ssh-keygen.1] - document -X and -x [ssh-keygen.c] - simplify usage - markus@cvs.openbsd.org [sshd.8] - there is no rhosts_dsa [ssh-keygen.1] - document -y, update -X,-x [nchan.c] - fix close for non-open ssh1 channels [servconf.c servconf.h ssh.h sshd.8 sshd.c ] - s/DsaKey/HostDSAKey/, document option [sshconnect2.c] - respect number_of_password_prompts [channels.c channels.h servconf.c servconf.h session.c sshd.8] - GatewayPorts for sshd, ok deraadt@ [ssh-add.1 ssh-agent.1 ssh.1] - more doc on: DSA, id_dsa, known_hosts2, authorized_keys2 [ssh.1] - more info on proto 2 [sshd.8] - sync AUTHOR w/ ssh.1 [key.c key.h sshconnect.c] - print key type when talking about host keys [packet.c] - clear padding in ssh2 [dsa.c key.c radix.c ssh.h sshconnect1.c uuencode.c uuencode.h] - replace broken uuencode w/ libc b64_ntop [auth2.c] - log failure before sending the reply [key.c radix.c uuencode.c] - remote trailing comments before calling __b64_pton [auth2.c readconf.c readconf.h servconf.c servconf.h ssh.1] [sshconnect2.c sshd.8] - add DSAAuthetication option to ssh/sshd, document SSH2 in sshd.8 - Bring in b64_ntop and b64_pton from OpenBSD libc (bsd-base64.[ch])
2000-05-07 02:03:14 +00:00
debug("Host '%.200s' is known and matches the %s host key.",
host, type);
debug("Found key in %s:%d", host_file, host_line);
if (options.check_host_ip && ip_status == HOST_NEW) {
if (readonly)
2003-04-09 10:59:48 +00:00
logit("%s host key for IP address "
"'%.128s' not in list of known hosts.",
type, ip);
else if (!add_host_to_hostfile(user_hostfile, ip,
host_key, options.hash_known_hosts))
2003-04-09 10:59:48 +00:00
logit("Failed to add the %s host key for IP "
"address '%.128s' to the list of known "
"hosts (%.30s).", type, ip, user_hostfile);
else
2003-04-09 10:59:48 +00:00
logit("Warning: Permanently added the %s host "
"key for IP address '%.128s' to the list "
"of known hosts.", type, ip);
}
break;
case HOST_NEW:
if (options.host_key_alias == NULL && port != 0 &&
port != SSH_DEFAULT_PORT) {
debug("checking without port identifier");
if (check_host_key(hostname, hostaddr, 0, host_key, 2,
user_hostfile, system_hostfile) == 0) {
debug("found matching key w/out port");
break;
}
}
if (readonly)
goto fail;
/* The host is new. */
if (options.strict_host_key_checking == 1) {
/*
* User has requested strict host key checking. We
* will not add the host key automatically. The only
* alternative left is to abort.
*/
error("No %s host key is known for %.200s and you "
"have requested strict checking.", type, host);
goto fail;
} else if (options.strict_host_key_checking == 2) {
char msg1[1024], msg2[1024];
if (show_other_keys(host, host_key))
snprintf(msg1, sizeof(msg1),
"\nbut keys of different type are already"
" known for this host.");
else
snprintf(msg1, sizeof(msg1), ".");
/* The default */
fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
msg2[0] = '\0';
if (options.verify_host_key_dns) {
if (matching_host_key_dns)
snprintf(msg2, sizeof(msg2),
"Matching host key fingerprint"
" found in DNS.\n");
else
snprintf(msg2, sizeof(msg2),
"No matching host key fingerprint"
" found in DNS.\n");
}
snprintf(msg, sizeof(msg),
"The authenticity of host '%.200s (%s)' can't be "
"established%s\n"
"%s key fingerprint is %s.\n%s"
"Are you sure you want to continue connecting "
"(yes/no)? ",
host, ip, msg1, type, fp, msg2);
xfree(fp);
if (!confirm(msg))
goto fail;
}
/*
* If not in strict mode, add the key automatically to the
* local known_hosts file.
*/
if (options.check_host_ip && ip_status == HOST_NEW) {
snprintf(hostline, sizeof(hostline), "%s,%s",
host, ip);
hostp = hostline;
if (options.hash_known_hosts) {
/* Add hash of host and IP separately */
r = add_host_to_hostfile(user_hostfile, host,
host_key, options.hash_known_hosts) &&
add_host_to_hostfile(user_hostfile, ip,
host_key, options.hash_known_hosts);
} else {
/* Add unhashed "host,ip" */
r = add_host_to_hostfile(user_hostfile,
hostline, host_key,
options.hash_known_hosts);
}
} else {
r = add_host_to_hostfile(user_hostfile, host, host_key,
options.hash_known_hosts);
hostp = host;
}
if (!r)
2003-04-09 10:59:48 +00:00
logit("Failed to add the host to the list of known "
"hosts (%.500s).", user_hostfile);
else
2003-04-09 10:59:48 +00:00
logit("Warning: Permanently added '%.200s' (%s) to the "
"list of known hosts.", hostp, type);
break;
case HOST_CHANGED:
if (readonly == ROQUIET)
goto fail;
if (options.check_host_ip && host_ip_differ) {
char *key_msg;
if (ip_status == HOST_NEW)
key_msg = "is unknown";
else if (ip_status == HOST_OK)
key_msg = "is unchanged";
else
key_msg = "has a different value";
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
- Remove references to SSLeay. - Big OpenBSD CVS update - markus@cvs.openbsd.org [clientloop.c] - typo [session.c] - update proctitle on pty alloc/dealloc, e.g. w/ windows client [session.c] - update proctitle for proto 1, too [channels.h nchan.c serverloop.c session.c sshd.c] - use c-style comments - deraadt@cvs.openbsd.org [scp.c] - more atomicio - markus@cvs.openbsd.org [channels.c] - set O_NONBLOCK [ssh.1] - update AUTHOR [readconf.c ssh-keygen.c ssh.h] - default DSA key file ~/.ssh/id_dsa [clientloop.c] - typo, rm verbose debug - deraadt@cvs.openbsd.org [ssh-keygen.1] - document DSA use of ssh-keygen [sshd.8] - a start at describing what i understand of the DSA side [ssh-keygen.1] - document -X and -x [ssh-keygen.c] - simplify usage - markus@cvs.openbsd.org [sshd.8] - there is no rhosts_dsa [ssh-keygen.1] - document -y, update -X,-x [nchan.c] - fix close for non-open ssh1 channels [servconf.c servconf.h ssh.h sshd.8 sshd.c ] - s/DsaKey/HostDSAKey/, document option [sshconnect2.c] - respect number_of_password_prompts [channels.c channels.h servconf.c servconf.h session.c sshd.8] - GatewayPorts for sshd, ok deraadt@ [ssh-add.1 ssh-agent.1 ssh.1] - more doc on: DSA, id_dsa, known_hosts2, authorized_keys2 [ssh.1] - more info on proto 2 [sshd.8] - sync AUTHOR w/ ssh.1 [key.c key.h sshconnect.c] - print key type when talking about host keys [packet.c] - clear padding in ssh2 [dsa.c key.c radix.c ssh.h sshconnect1.c uuencode.c uuencode.h] - replace broken uuencode w/ libc b64_ntop [auth2.c] - log failure before sending the reply [key.c radix.c uuencode.c] - remote trailing comments before calling __b64_pton [auth2.c readconf.c readconf.h servconf.c servconf.h ssh.1] [sshconnect2.c sshd.8] - add DSAAuthetication option to ssh/sshd, document SSH2 in sshd.8 - Bring in b64_ntop and b64_pton from OpenBSD libc (bsd-base64.[ch])
2000-05-07 02:03:14 +00:00
error("The %s host key for %s has changed,", type, host);
error("and the key for the according IP address %s", ip);
error("%s. This could either mean that", key_msg);
error("DNS SPOOFING is happening or the IP address for the host");
error("and its host key have changed at the same time.");
if (ip_status != HOST_NEW)
error("Offending key for IP in %s:%d", ip_file, ip_line);
}
/* The host key has changed. */
warn_changed_key(host_key);
error("Add correct host key in %.100s to get rid of this message.",
user_hostfile);
error("Offending key in %s:%d", host_file, host_line);
/*
* If strict host key checking is in use, the user will have
* to edit the key manually and we can only abort.
*/
if (options.strict_host_key_checking) {
error("%s host key for %.200s has changed and you have "
"requested strict checking.", type, host);
goto fail;
}
/*
* If strict host key checking has not been requested, allow
* the connection but without MITM-able authentication or
* forwarding.
*/
if (options.password_authentication) {
error("Password authentication is disabled to avoid "
"man-in-the-middle attacks.");
options.password_authentication = 0;
}
if (options.kbd_interactive_authentication) {
error("Keyboard-interactive authentication is disabled"
" to avoid man-in-the-middle attacks.");
options.kbd_interactive_authentication = 0;
options.challenge_response_authentication = 0;
}
if (options.challenge_response_authentication) {
error("Challenge/response authentication is disabled"
" to avoid man-in-the-middle attacks.");
options.challenge_response_authentication = 0;
}
if (options.forward_agent) {
error("Agent forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.forward_agent = 0;
}
if (options.forward_x11) {
error("X11 forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.forward_x11 = 0;
}
if (options.num_local_forwards > 0 ||
options.num_remote_forwards > 0) {
error("Port forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.num_local_forwards =
options.num_remote_forwards = 0;
}
if (options.tun_open != SSH_TUNMODE_NO) {
error("Tunnel forwarding is disabled to avoid "
"man-in-the-middle attacks.");
options.tun_open = SSH_TUNMODE_NO;
}
/*
* XXX Should permit the user to change to use the new id.
* This could be done by converting the host key to an
* identifying sentence, tell that the host identifies itself
* by that sentence, and ask the user if he/she whishes to
* accept the authentication.
*/
break;
case HOST_FOUND:
fatal("internal error");
break;
}
if (options.check_host_ip && host_status != HOST_CHANGED &&
ip_status == HOST_CHANGED) {
snprintf(msg, sizeof(msg),
"Warning: the %s host key for '%.200s' "
"differs from the key for the IP address '%.128s'"
"\nOffending key for IP in %s:%d",
type, host, ip, ip_file, ip_line);
if (host_status == HOST_OK) {
len = strlen(msg);
snprintf(msg + len, sizeof(msg) - len,
"\nMatching host key in %s:%d",
host_file, host_line);
}
if (options.strict_host_key_checking == 1) {
logit("%s", msg);
error("Exiting, you have requested strict checking.");
goto fail;
} else if (options.strict_host_key_checking == 2) {
strlcat(msg, "\nAre you sure you want "
"to continue connecting (yes/no)? ", sizeof(msg));
if (!confirm(msg))
goto fail;
} else {
logit("%s", msg);
}
}
xfree(ip);
xfree(host);
return 0;
fail:
xfree(ip);
xfree(host);
return -1;
}
/* returns 0 if key verifies or -1 if key does NOT verify */
int
verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
{
struct stat st;
int flags = 0;
if (options.verify_host_key_dns &&
verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
if (flags & DNS_VERIFY_FOUND) {
if (options.verify_host_key_dns == 1 &&
flags & DNS_VERIFY_MATCH &&
flags & DNS_VERIFY_SECURE)
return 0;
if (flags & DNS_VERIFY_MATCH) {
matching_host_key_dns = 1;
} else {
warn_changed_key(host_key);
error("Update the SSHFP RR in DNS with the new "
"host key to get rid of this message.");
}
}
}
/* return ok if the key can be found in an old keyfile */
if (stat(options.system_hostfile2, &st) == 0 ||
stat(options.user_hostfile2, &st) == 0) {
if (check_host_key(host, hostaddr, options.port, host_key,
RDONLY, options.user_hostfile2,
options.system_hostfile2) == 0)
return 0;
}
return check_host_key(host, hostaddr, options.port, host_key,
RDRW, options.user_hostfile, options.system_hostfile);
}
/*
* Starts a dialog with the server, and authenticates the current user on the
* server. This does not need any extra privileges. The basic connection
* to the server must already have been established before this is called.
* If login fails, this function prints an error and never returns.
* This function does not require super-user privileges.
*/
void
ssh_login(Sensitive *sensitive, const char *orighost,
struct sockaddr *hostaddr, struct passwd *pw, int timeout_ms)
{
char *host, *cp;
char *server_user, *local_user;
local_user = xstrdup(pw->pw_name);
server_user = options.user ? options.user : local_user;
/* Convert the user-supplied hostname into all lowercase. */
host = xstrdup(orighost);
for (cp = host; *cp; cp++)
if (isupper(*cp))
*cp = (char)tolower(*cp);
/* Exchange protocol version identification strings with the server. */
ssh_exchange_identification(timeout_ms);
/* Put the connection into non-blocking mode. */
packet_set_nonblocking();
/* key exchange */
/* authenticate user */
if (compat20) {
ssh_kex2(host, hostaddr);
ssh_userauth2(local_user, server_user, host, sensitive);
} else {
ssh_kex(host, hostaddr);
ssh_userauth1(local_user, server_user, host, sensitive);
}
xfree(local_user);
}
void
ssh_put_password(char *password)
{
int size;
char *padded;
if (datafellows & SSH_BUG_PASSWORDPAD) {
packet_put_cstring(password);
return;
}
size = roundup(strlen(password) + 1, 32);
padded = xcalloc(1, size);
strlcpy(padded, password, size);
packet_put_string(padded, size);
memset(padded, 0, size);
xfree(padded);
}
static int
show_key_from_file(const char *file, const char *host, int keytype)
{
Key *found;
char *fp;
int line, ret;
found = key_new(keytype);
if ((ret = lookup_key_in_hostfile_by_type(file, host,
keytype, found, &line))) {
fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
2003-04-09 10:59:48 +00:00
logit("WARNING: %s key found for host %s\n"
"in %s:%d\n"
"%s key fingerprint %s.",
key_type(found), host, file, line,
key_type(found), fp);
xfree(fp);
}
key_free(found);
return (ret);
}
/* print all known host keys for a given host, but skip keys of given type */
static int
show_other_keys(const char *host, Key *key)
{
int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1};
int i, found = 0;
for (i = 0; type[i] != -1; i++) {
if (type[i] == key->type)
continue;
if (type[i] != KEY_RSA1 &&
show_key_from_file(options.user_hostfile2, host, type[i])) {
found = 1;
continue;
}
if (type[i] != KEY_RSA1 &&
show_key_from_file(options.system_hostfile2, host, type[i])) {
found = 1;
continue;
}
if (show_key_from_file(options.user_hostfile, host, type[i])) {
found = 1;
continue;
}
if (show_key_from_file(options.system_hostfile, host, type[i])) {
found = 1;
continue;
}
debug2("no key of type %d for host %s", type[i], host);
}
return (found);
}
static void
warn_changed_key(Key *host_key)
{
char *fp;
const char *type = key_type(host_key);
fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
error("It is also possible that the %s host key has just been changed.", type);
error("The fingerprint for the %s key sent by the remote host is\n%s.",
type, fp);
error("Please contact your system administrator.");
xfree(fp);
}
/*
* Execute a local command
*/
int
ssh_local_cmd(const char *args)
{
char *shell;
pid_t pid;
int status;
if (!options.permit_local_command ||
args == NULL || !*args)
return (1);
if ((shell = getenv("SHELL")) == NULL)
shell = _PATH_BSHELL;
pid = fork();
if (pid == 0) {
debug3("Executing %s -c \"%s\"", shell, args);
execl(shell, shell, "-c", args, (char *)NULL);
error("Couldn't execute %s -c \"%s\": %s",
shell, args, strerror(errno));
_exit(1);
} else if (pid == -1)
fatal("fork failed: %.100s", strerror(errno));
while (waitpid(pid, &status, 0) == -1)
if (errno != EINTR)
fatal("Couldn't wait for child: %s", strerror(errno));
if (!WIFEXITED(status))
return (1);
return (WEXITSTATUS(status));
}