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-rw-r--r--crypto/openssh/sshconnect.c926
1 files changed, 0 insertions, 926 deletions
diff --git a/crypto/openssh/sshconnect.c b/crypto/openssh/sshconnect.c
deleted file mode 100644
index dae25969a49d9..0000000000000
--- a/crypto/openssh/sshconnect.c
+++ /dev/null
@@ -1,926 +0,0 @@
-/*
- * 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.
- *
- * 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".
- */
-
-#include "includes.h"
-RCSID("$OpenBSD: sshconnect.c,v 1.137 2002/11/21 23:03:51 deraadt Exp $");
-
-#include <openssl/bn.h>
-
-#include "ssh.h"
-#include "xmalloc.h"
-#include "rsa.h"
-#include "buffer.h"
-#include "packet.h"
-#include "uidswap.h"
-#include "compat.h"
-#include "key.h"
-#include "sshconnect.h"
-#include "hostfile.h"
-#include "log.h"
-#include "readconf.h"
-#include "atomicio.h"
-#include "misc.h"
-#include "readpass.h"
-
-char *client_version_string = NULL;
-char *server_version_string = NULL;
-
-/* 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 *);
-
-/*
- * 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)
-{
- Buffer command;
- const char *cp;
- char *command_string;
- int pin[2], pout[2];
- pid_t pid;
- char strport[NI_MAXSERV];
-
- /* 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)
- */
- buffer_init(&command);
- buffer_append(&command, "exec ", 5);
-
- for (cp = proxy_command; *cp; cp++) {
- if (cp[0] == '%' && cp[1] == '%') {
- buffer_append(&command, "%", 1);
- cp++;
- continue;
- }
- if (cp[0] == '%' && cp[1] == 'h') {
- buffer_append(&command, host, strlen(host));
- cp++;
- continue;
- }
- if (cp[0] == '%' && cp[1] == 'p') {
- buffer_append(&command, strport, strlen(strport));
- cp++;
- continue;
- }
- buffer_append(&command, cp, 1);
- }
- buffer_append(&command, "\0", 1);
-
- /* Get the final command string. */
- command_string = buffer_ptr(&command);
-
- /* 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. */
- seteuid(original_real_uid);
- setuid(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] = _PATH_BSHELL;
- argv[1] = "-c";
- argv[2] = command_string;
- argv[3] = NULL;
-
- /* Execute the proxy command. Note that we gave up any
- extra privileges above. */
- execv(argv[0], argv);
- perror(argv[0]);
- exit(1);
- }
- /* 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. */
- buffer_free(&command);
-
- /* Set the connection file descriptors. */
- packet_set_connection(pout[0], pin[1]);
-
- /* Indicate OK return */
- return 0;
-}
-
-/*
- * Creates a (possibly privileged) socket for use as the ssh connection.
- */
-static int
-ssh_create_socket(int privileged, int family)
-{
- 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, family);
- PRIV_END;
- if (sock < 0)
- error("rresvport: af=%d %.100s", family, strerror(errno));
- else
- debug("Allocated local port %d.", p);
- return sock;
- }
- sock = socket(family, SOCK_STREAM, 0);
- 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 = family;
- hints.ai_socktype = SOCK_STREAM;
- hints.ai_flags = AI_PASSIVE;
- gaierr = getaddrinfo(options.bind_address, "0", &hints, &res);
- if (gaierr) {
- error("getaddrinfo: %s: %s", options.bind_address,
- 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;
-}
-
-/*
- * 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.
- * Return values:
- * 0 for OK
- * ECONNREFUSED if we got a "Connection Refused" by the peer on any address
- * ECONNABORTED if we failed without a "Connection refused"
- * Suitable error messages for the connection failure will already have been
- * printed.
- */
-int
-ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
- u_short port, int family, int connection_attempts,
- int needpriv, const char *proxy_command)
-{
- int gaierr;
- int on = 1;
- int sock = -1, attempt;
- char ntop[NI_MAXHOST], strport[NI_MAXSERV];
- struct addrinfo hints, *ai, *aitop;
- struct servent *sp;
- /*
- * Did we get only other errors than "Connection refused" (which
- * should block fallback to rsh and similar), or did we get at least
- * one "Connection refused"?
- */
- int full_failure = 1;
-
- debug2("ssh_connect: needpriv %d", needpriv);
-
- /* Get default port if port has not been set. */
- if (port == 0) {
- sp = getservbyname(SSH_SERVICE_NAME, "tcp");
- if (sp)
- port = ntohs(sp->s_port);
- else
- port = SSH_DEFAULT_PORT;
- }
- /* 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: %.100s: %s", __progname, host,
- gai_strerror(gaierr));
-
- /*
- * Try to connect several times. On some machines, the first time
- * will sometimes fail. In general socket code appears to behave
- * quite magically on many machines.
- */
- for (attempt = 0; ;) {
- if (attempt > 0)
- 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->ai_family);
- if (sock < 0)
- /* Any error is already output */
- continue;
-
- if (connect(sock, ai->ai_addr, ai->ai_addrlen) >= 0) {
- /* Successful connection. */
- memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
- break;
- } else {
- if (errno == ECONNREFUSED)
- full_failure = 0;
- debug("connect to address %s port %s: %s",
- ntop, strport, strerror(errno));
- /*
- * Close the failed socket; there appear to
- * be some problems when reusing a socket for
- * which connect() has already returned an
- * error.
- */
- close(sock);
- }
- }
- if (ai)
- break; /* Successful connection. */
-
- attempt++;
- if (attempt >= connection_attempts)
- break;
- /* Sleep a moment before retrying. */
- sleep(1);
- }
-
- freeaddrinfo(aitop);
-
- /* Return failure if we didn't get a successful connection. */
- if (attempt >= connection_attempts) {
- log("ssh: connect to host %s port %s: %s",
- host, strport, strerror(errno));
- return full_failure ? ECONNABORTED : ECONNREFUSED;
- }
-
- debug("Connection established.");
-
- /* Set keepalives if requested. */
- if (options.keepalives &&
- setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
- sizeof(on)) < 0)
- error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
-
- /* Set the connection. */
- packet_set_connection(sock, sock);
-
- return 0;
-}
-
-/*
- * Waits for the server identification string, and sends our own
- * identification string.
- */
-static void
-ssh_exchange_identification(void)
-{
- char buf[256], remote_version[256]; /* must be same size! */
- int remote_major, remote_minor, i, mismatch;
- int connection_in = packet_get_connection_in();
- int connection_out = packet_get_connection_out();
- int minor1 = PROTOCOL_MINOR_1;
-
- /* Read other side\'s version identification. */
- for (;;) {
- for (i = 0; i < sizeof(buf) - 1; i++) {
- int len = atomicio(read, connection_in, &buf[i], 1);
- if (len < 0)
- fatal("ssh_exchange_identification: read: %.100s", strerror(errno));
- if (len != 1)
- fatal("ssh_exchange_identification: Connection closed by remote host");
- 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;
- }
- }
- buf[sizeof(buf) - 1] = 0;
- if (strncmp(buf, "SSH-", 4) == 0)
- break;
- debug("ssh_exchange_identification: %s", buf);
- }
- server_version_string = xstrdup(buf);
-
- /*
- * 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.");
- } else if (remote_minor == 3 || remote_minor == 4) {
- /* We speak 1.3, too. */
- enable_compat13();
- minor1 = 3;
- if (options.forward_agent) {
- log("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;
- }
- 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,
- compat20 ? PROTOCOL_MINOR_2 : minor1,
- SSH_VERSION);
- if (atomicio(write, 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);
-}
-
-/* defaults to 'no' */
-static int
-confirm(const char *prompt)
-{
- 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;
- }
-}
-
-/*
- * 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.
- */
-static int
-check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key,
- int readonly, const char *user_hostfile, const char *system_hostfile)
-{
- Key *file_key;
- char *type = key_type(host_key);
- char *ip = NULL;
- char hostline[1000], *hostp, *fp;
- HostStatus host_status;
- HostStatus ip_status;
- int local = 0, host_ip_differ = 0;
- int salen;
- char ntop[NI_MAXHOST];
- char msg[1024];
- int len, host_line, ip_line, has_keys;
- 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 = xstrdup(ntop);
- } 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(host, ip) == 0 || options.proxy_command != NULL))
- options.check_host_ip = 0;
-
- /*
- * Allow the user to record the key under a different name. 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 = options.host_key_alias;
- debug("using hostkeyalias: %s", host);
- }
-
- /*
- * 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. */
- 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)
- log("%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))
- log("Failed to add the %s host key for IP "
- "address '%.128s' to the list of known "
- "hosts (%.30s).", type, ip, user_hostfile);
- else
- log("Warning: Permanently added the %s host "
- "key for IP address '%.128s' to the list "
- "of known hosts.", type, ip);
- }
- break;
- case HOST_NEW:
- 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) {
- has_keys = show_other_keys(host, host_key);
- /* The default */
- fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
- snprintf(msg, sizeof(msg),
- "The authenticity of host '%.200s (%s)' can't be "
- "established%s\n"
- "%s key fingerprint is %s.\n"
- "Are you sure you want to continue connecting "
- "(yes/no)? ",
- host, ip,
- has_keys ? ",\nbut keys of different type are already "
- "known for this host." : ".",
- type, fp);
- xfree(fp);
- if (!confirm(msg))
- goto fail;
- }
- if (options.check_host_ip && ip_status == HOST_NEW) {
- snprintf(hostline, sizeof(hostline), "%s,%s", host, ip);
- hostp = hostline;
- } else
- hostp = host;
-
- /*
- * If not in strict mode, add the key automatically to the
- * local known_hosts file.
- */
- if (!add_host_to_hostfile(user_hostfile, hostp, host_key))
- log("Failed to add the host to the list of known "
- "hosts (%.500s).", user_hostfile);
- else
- log("Warning: Permanently added '%.200s' (%s) to the "
- "list of known hosts.", hostp, type);
- break;
- case HOST_CHANGED:
- if (options.check_host_ip && host_ip_differ) {
- char *msg;
- if (ip_status == HOST_NEW)
- msg = "is unknown";
- else if (ip_status == HOST_OK)
- msg = "is unchanged";
- else
- msg = "has a different value";
- error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
- error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
- error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
- 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", 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. */
- 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.");
- 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);
- xfree(fp);
-
- /*
- * 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 password authentication or
- * agent forwarding.
- */
- if (options.password_authentication) {
- error("Password authentication is disabled to avoid "
- "man-in-the-middle attacks.");
- options.password_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;
- }
- /*
- * 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) {
- log(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 {
- log(msg);
- }
- }
-
- xfree(ip);
- return 0;
-
-fail:
- xfree(ip);
- return -1;
-}
-
-int
-verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
-{
- struct stat st;
-
- /* 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, host_key, /*readonly*/ 1,
- options.user_hostfile2, options.system_hostfile2) == 0)
- return 0;
- }
- return check_host_key(host, hostaddr, host_key, /*readonly*/ 0,
- 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)
-{
- 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 = tolower(*cp);
-
- /* Exchange protocol version identification strings with the server. */
- ssh_exchange_identification();
-
- /* 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);
- }
-}
-
-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 = xmalloc(size);
- memset(padded, 0, 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);
- log("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);
-}