*/
#include "includes.h"
-RCSID("$Id$");
+RCSID("$OpenBSD: sshd.c,v 1.80 2000/01/20 15:19:22 markus Exp $");
#include "xmalloc.h"
#include "rsa.h"
/* Name of the server configuration file. */
char *config_file_name = SERVER_CONFIG_FILE;
+/*
+ * Flag indicating whether IPv4 or IPv6. This can be set on the command line.
+ * Default value is AF_UNSPEC means both IPv4 and IPv6.
+ */
+#ifdef IPV4_DEFAULT
+int IPv4or6 = AF_INET;
+#else
+int IPv4or6 = AF_UNSPEC;
+#endif
+
/*
* Debug mode flag. This can be set on the command line. If debug
* mode is enabled, extra debugging output will be sent to the system
/* Saved arguments to main(). */
char **saved_argv;
-/* This is set to the socket that the server is listening; this is used in
- the SIGHUP signal handler. */
-int listen_sock;
+/*
+ * The sockets that the server is listening; this is used in the SIGHUP
+ * signal handler.
+ */
+#define MAX_LISTEN_SOCKS 16
+int listen_socks[MAX_LISTEN_SOCKS];
+int num_listen_socks = 0;
-/* the client's version string, passed by sshd2 in compat mode.
- if != NULL, sshd will skip the version-number exchange */
+/*
+ * the client's version string, passed by sshd2 in compat mode. if != NULL,
+ * sshd will skip the version-number exchange
+ */
char *client_version_string = NULL;
/* Flags set in auth-rsa from authorized_keys flags. These are set in auth-rsa.c. */
/* Session id for the current session. */
unsigned char session_id[16];
-/* Any really sensitive data in the application is contained in this structure.
- The idea is that this structure could be locked into memory so that the
- pages do not get written into swap. However, there are some problems.
- The private key contains BIGNUMs, and we do not (in principle) have
- access to the internals of them, and locking just the structure is not
- very useful. Currently, memory locking is not implemented. */
+/*
+ * Any really sensitive data in the application is contained in this
+ * structure. The idea is that this structure could be locked into memory so
+ * that the pages do not get written into swap. However, there are some
+ * problems. The private key contains BIGNUMs, and we do not (in principle)
+ * have access to the internals of them, and locking just the structure is
+ * not very useful. Currently, memory locking is not implemented.
+ */
struct {
RSA *private_key; /* Private part of server key. */
RSA *host_key; /* Private part of host key. */
} sensitive_data;
-/* Flag indicating whether the current session key has been used. This flag
- is set whenever the key is used, and cleared when the key is regenerated. */
+/*
+ * Flag indicating whether the current session key has been used. This flag
+ * is set whenever the key is used, and cleared when the key is regenerated.
+ */
int key_used = 0;
/* This is set to true when SIGHUP is received. */
RSA *public_key;
/* Prototypes for various functions defined later in this file. */
-void do_connection();
-void do_authentication(char *user);
+void do_ssh_kex();
+void do_authentication();
void do_authloop(struct passwd * pw);
void do_fake_authloop(char *user);
void do_authenticated(struct passwd * pw);
const char *display, const char *auth_proto,
const char *auth_data, const char *ttyname);
-#ifdef HAVE_LIBPAM
-static int pamconv(int num_msg, const struct pam_message **msg,
- struct pam_response **resp, void *appdata_ptr);
-void do_pam_account_and_session(char *username, char *remote_user,
- const char *remote_host);
-void pam_cleanup_proc(void *context);
-
-static struct pam_conv conv = {
- pamconv,
- NULL
-};
-struct pam_handle_t *pamh = NULL;
-const char *pampasswd = NULL;
-char *pamconv_msg = NULL;
-
-static int pamconv(int num_msg, const struct pam_message **msg,
- struct pam_response **resp, void *appdata_ptr)
-{
- struct pam_response *reply;
- int count;
- size_t msg_len;
- char *p;
-
- /* PAM will free this later */
- reply = malloc(num_msg * sizeof(*reply));
- if (reply == NULL)
- return PAM_CONV_ERR;
-
- for(count = 0; count < num_msg; count++) {
- switch (msg[count]->msg_style) {
- case PAM_PROMPT_ECHO_OFF:
- if (pampasswd == NULL) {
- free(reply);
- return PAM_CONV_ERR;
- }
- reply[count].resp_retcode = PAM_SUCCESS;
- reply[count].resp = xstrdup(pampasswd);
- break;
-
- case PAM_TEXT_INFO:
- reply[count].resp_retcode = PAM_SUCCESS;
- reply[count].resp = xstrdup("");
-
- if (msg[count]->msg == NULL)
- break;
-
- debug("Adding PAM message: %s", msg[count]->msg);
-
- msg_len = strlen(msg[count]->msg);
- if (pamconv_msg) {
- size_t n = strlen(pamconv_msg);
- pamconv_msg = xrealloc(pamconv_msg, n + msg_len + 2);
- p = pamconv_msg + n;
- } else {
- pamconv_msg = p = xmalloc(msg_len + 2);
- }
- memcpy(p, msg[count]->msg, msg_len);
- p[msg_len] = '\n';
- p[msg_len + 1] = '\0';
- break;
-
- case PAM_PROMPT_ECHO_ON:
- case PAM_ERROR_MSG:
- default:
- free(reply);
- return PAM_CONV_ERR;
- }
- }
-
- *resp = reply;
-
- return PAM_SUCCESS;
-}
-
-void pam_cleanup_proc(void *context)
-{
- int pam_retval;
-
- if (pamh != NULL)
- {
- pam_retval = pam_close_session((pam_handle_t *)pamh, 0);
- if (pam_retval != PAM_SUCCESS) {
- log("Cannot close PAM session: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- }
-
- pam_retval = pam_end((pam_handle_t *)pamh, pam_retval);
- if (pam_retval != PAM_SUCCESS) {
- log("Cannot release PAM authentication: %.200s",
- PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- }
- }
-}
-
-void do_pam_account_and_session(char *username, char *remote_user,
- const char *remote_host)
+/*
+ * Close all listening sockets
+ */
+void
+close_listen_socks(void)
{
- int pam_retval;
-
- if (remote_host != NULL) {
- debug("PAM setting rhost to \"%.200s\"", remote_host);
- pam_retval = pam_set_item((pam_handle_t *)pamh, PAM_RHOST, remote_host);
- if (pam_retval != PAM_SUCCESS) {
- log("PAM set rhost failed: %.200s", PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- do_fake_authloop(username);
- }
- }
-
- if (remote_user != NULL) {
- debug("PAM setting ruser to \"%.200s\"", remote_user);
- pam_retval = pam_set_item((pam_handle_t *)pamh, PAM_RUSER, remote_user);
- if (pam_retval != PAM_SUCCESS) {
- log("PAM set ruser failed: %.200s", PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- do_fake_authloop(username);
- }
- }
-
- pam_retval = pam_acct_mgmt((pam_handle_t *)pamh, 0);
- if (pam_retval != PAM_SUCCESS) {
- log("PAM rejected by account configuration: %.200s", PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- do_fake_authloop(username);
- }
-
- pam_retval = pam_open_session((pam_handle_t *)pamh, 0);
- if (pam_retval != PAM_SUCCESS) {
- log("PAM session setup failed: %.200s", PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- do_fake_authloop(username);
- }
+ int i;
+ for (i = 0; i < num_listen_socks; i++)
+ close(listen_socks[i]);
+ num_listen_socks = -1;
}
-#endif /* HAVE_LIBPAM */
/*
* Signal handler for SIGHUP. Sshd execs itself when it receives SIGHUP;
sighup_restart()
{
log("Received SIGHUP; restarting.");
- close(listen_sock);
+ close_listen_socks();
execv(saved_argv[0], saved_argv);
log("RESTART FAILED: av0='%s', error: %s.", av0, strerror(errno));
exit(1);
sigterm_handler(int sig)
{
log("Received signal %d; terminating.", sig);
- close(listen_sock);
+ close_listen_socks();
exit(255);
}
{
extern char *optarg;
extern int optind;
- int opt, aux, sock_in, sock_out, newsock, i, pid, on = 1;
+ int opt, sock_in = 0, sock_out = 0, newsock, i, fdsetsz, pid, on = 1;
+ socklen_t fromlen;
int remote_major, remote_minor;
int silentrsa = 0;
- struct sockaddr_in sin;
+ fd_set *fdset;
+ struct sockaddr_storage from;
char buf[100]; /* Must not be larger than remote_version. */
char remote_version[100]; /* Must be at least as big as buf. */
const char *remote_ip;
char *comment;
FILE *f;
struct linger linger;
+ struct addrinfo *ai;
+ char ntop[NI_MAXHOST], strport[NI_MAXSERV];
+ int listen_sock, maxfd;
/* Save argv[0]. */
saved_argv = av;
initialize_server_options(&options);
/* Parse command-line arguments. */
- while ((opt = getopt(ac, av, "f:p:b:k:h:g:V:diqQ")) != EOF) {
+ while ((opt = getopt(ac, av, "f:p:b:k:h:g:V:diqQ46")) != EOF) {
switch (opt) {
+ case '4':
+ IPv4or6 = AF_INET;
+ break;
+ case '6':
+ IPv4or6 = AF_INET6;
+ break;
case 'f':
config_file_name = optarg;
break;
options.server_key_bits = atoi(optarg);
break;
case 'p':
- options.port = atoi(optarg);
+ options.ports_from_cmdline = 1;
+ if (options.num_ports >= MAX_PORTS)
+ fatal("too many ports.\n");
+ options.ports[options.num_ports++] = atoi(optarg);
break;
case 'g':
options.login_grace_time = atoi(optarg);
fprintf(stderr, "sshd version %s\n", SSH_VERSION);
fprintf(stderr, "Usage: %s [options]\n", av0);
fprintf(stderr, "Options:\n");
- fprintf(stderr, " -f file Configuration file (default %s/sshd_config)\n", ETCDIR);
+ fprintf(stderr, " -f file Configuration file (default %s)\n", SERVER_CONFIG_FILE);
fprintf(stderr, " -d Debugging mode\n");
fprintf(stderr, " -i Started from inetd\n");
fprintf(stderr, " -q Quiet (no logging)\n");
fprintf(stderr, " -g seconds Grace period for authentication (default: 300)\n");
fprintf(stderr, " -b bits Size of server RSA key (default: 768 bits)\n");
fprintf(stderr, " -h file File from which to read host key (default: %s)\n",
- HOST_KEY_FILE);
+ HOST_KEY_FILE);
+ fprintf(stderr, " -4 Use IPv4 only\n");
+ fprintf(stderr, " -6 Use IPv6 only\n");
exit(1);
}
}
+ /*
+ * Force logging to stderr until we have loaded the private host
+ * key (unless started from inetd)
+ */
+ log_init(av0,
+ options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
+ options.log_facility == -1 ? SYSLOG_FACILITY_AUTH : options.log_facility,
+ !inetd_flag);
+
/* check if RSA support exists */
if (rsa_alive() == 0) {
if (silentrsa == 0)
fprintf(stderr, "Bad server key size.\n");
exit(1);
}
- if (options.port < 1 || options.port > 65535) {
- fprintf(stderr, "Bad port number.\n");
- exit(1);
- }
/* Check that there are no remaining arguments. */
if (optind < ac) {
fprintf(stderr, "Extra argument %s.\n", av[optind]);
exit(1);
}
- /* Force logging to stderr while loading the private host key
- unless started from inetd */
- log_init(av0, options.log_level, options.log_facility, !inetd_flag);
debug("sshd version %.100s", SSH_VERSION);
arc4random_stir();
log("RSA key generation complete.");
} else {
- /* Create socket for listening. */
- listen_sock = socket(AF_INET, SOCK_STREAM, 0);
- if (listen_sock < 0)
- fatal("socket: %.100s", strerror(errno));
-
- /* Set socket options. We try to make the port reusable
- and have it close as fast as possible without waiting
- in unnecessary wait states on close. */
- setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, (void *) &on,
- sizeof(on));
- linger.l_onoff = 1;
- linger.l_linger = 5;
- setsockopt(listen_sock, SOL_SOCKET, SO_LINGER, (void *) &linger,
- sizeof(linger));
-
- /* Initialize the socket address. */
- memset(&sin, 0, sizeof(sin));
- sin.sin_family = AF_INET;
- sin.sin_addr = options.listen_addr;
- sin.sin_port = htons(options.port);
-
- /* Bind the socket to the desired port. */
- if (bind(listen_sock, (struct sockaddr *) & sin, sizeof(sin)) < 0) {
- error("bind: %.100s", strerror(errno));
- shutdown(listen_sock, SHUT_RDWR);
- close(listen_sock);
- fatal("Bind to port %d failed.", options.port);
+ for (ai = options.listen_addrs; ai; ai = ai->ai_next) {
+ if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
+ continue;
+ if (num_listen_socks >= MAX_LISTEN_SOCKS)
+ fatal("Too many listen sockets. "
+ "Enlarge MAX_LISTEN_SOCKS");
+ if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
+ ntop, sizeof(ntop), strport, sizeof(strport),
+ NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
+ error("getnameinfo failed");
+ continue;
+ }
+ /* Create socket for listening. */
+ listen_sock = socket(ai->ai_family, SOCK_STREAM, 0);
+ if (listen_sock < 0) {
+ /* kernel may not support ipv6 */
+ verbose("socket: %.100s", strerror(errno));
+ continue;
+ }
+ if (fcntl(listen_sock, F_SETFL, O_NONBLOCK) < 0) {
+ error("listen_sock O_NONBLOCK: %s", strerror(errno));
+ close(listen_sock);
+ continue;
+ }
+ /*
+ * Set socket options. We try to make the port
+ * reusable and have it close as fast as possible
+ * without waiting in unnecessary wait states on
+ * close.
+ */
+ setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR,
+ (void *) &on, sizeof(on));
+ linger.l_onoff = 1;
+ linger.l_linger = 5;
+ setsockopt(listen_sock, SOL_SOCKET, SO_LINGER,
+ (void *) &linger, sizeof(linger));
+
+ debug("Bind to port %s on %s.", strport, ntop);
+
+ /* Bind the socket to the desired port. */
+ if ((bind(listen_sock, ai->ai_addr, ai->ai_addrlen) < 0) &&
+ (!ai->ai_next)) {
+ error("Bind to port %s on %s failed: %.200s.",
+ strport, ntop, strerror(errno));
+ close(listen_sock);
+ continue;
+ }
+ listen_socks[num_listen_socks] = listen_sock;
+ num_listen_socks++;
+
+ /* Start listening on the port. */
+ log("Server listening on %s port %s.", ntop, strport);
+ if (listen(listen_sock, 5) < 0)
+ fatal("listen: %.100s", strerror(errno));
+
}
+ freeaddrinfo(options.listen_addrs);
+
+ if (!num_listen_socks)
+ fatal("Cannot bind any address.");
+
if (!debug_flag) {
- /* Record our pid in /etc/sshd_pid to make it
- easier to kill the correct sshd. We don\'t
- want to do this before the bind above because
- the bind will fail if there already is a
- daemon, and this will overwrite any old pid in
- the file. */
+ /*
+ * Record our pid in /etc/sshd_pid to make it easier
+ * to kill the correct sshd. We don\'t want to do
+ * this before the bind above because the bind will
+ * fail if there already is a daemon, and this will
+ * overwrite any old pid in the file.
+ */
f = fopen(SSH_DAEMON_PID_FILE, "w");
if (f) {
fprintf(f, "%u\n", (unsigned int) getpid());
}
}
- log("Server listening on port %d.", options.port);
- if (listen(listen_sock, 5) < 0)
- fatal("listen: %.100s", strerror(errno));
-
public_key = RSA_new();
sensitive_data.private_key = RSA_new();
/* Arrange SIGCHLD to be caught. */
signal(SIGCHLD, main_sigchld_handler);
- /* Stay listening for connections until the system crashes
- or the daemon is killed with a signal. */
+ /* setup fd set for listen */
+ maxfd = 0;
+ for (i = 0; i < num_listen_socks; i++)
+ if (listen_socks[i] > maxfd)
+ maxfd = listen_socks[i];
+ fdsetsz = howmany(maxfd, NFDBITS) * sizeof(fd_mask);
+ fdset = (fd_set *)xmalloc(fdsetsz);
+
+ /*
+ * Stay listening for connections until the system crashes or
+ * the daemon is killed with a signal.
+ */
for (;;) {
if (received_sighup)
sighup_restart();
- /* Wait in accept until there is a connection. */
- aux = sizeof(sin);
- newsock = accept(listen_sock, (struct sockaddr *) & sin, &aux);
- if (received_sighup)
- sighup_restart();
- if (newsock < 0) {
- if (errno == EINTR)
+ /* Wait in select until there is a connection. */
+ memset(fdset, 0, fdsetsz);
+ for (i = 0; i < num_listen_socks; i++)
+ FD_SET(listen_socks[i], fdset);
+ if (select(maxfd + 1, fdset, NULL, NULL, NULL) < 0) {
+ if (errno != EINTR)
+ error("select: %.100s", strerror(errno));
+ continue;
+ }
+ for (i = 0; i < num_listen_socks; i++) {
+ if (!FD_ISSET(listen_socks[i], fdset))
continue;
- error("accept: %.100s", strerror(errno));
+ fromlen = sizeof(from);
+ newsock = accept(listen_socks[i], (struct sockaddr *)&from,
+ &fromlen);
+ if (newsock < 0) {
+ if (errno != EINTR && errno != EWOULDBLOCK)
+ error("accept: %.100s", strerror(errno));
continue;
}
- /* Got connection. Fork a child to handle it,
- unless we are in debugging mode. */
+ if (fcntl(newsock, F_SETFL, 0) < 0) {
+ error("newsock del O_NONBLOCK: %s", strerror(errno));
+ continue;
+ }
+ /*
+ * Got connection. Fork a child to handle it, unless
+ * we are in debugging mode.
+ */
if (debug_flag) {
- /* In debugging mode. Close the listening
- socket, and start processing the
- connection without forking. */
+ /*
+ * In debugging mode. Close the listening
+ * socket, and start processing the
+ * connection without forking.
+ */
debug("Server will not fork when running in debugging mode.");
- close(listen_sock);
+ close_listen_socks();
sock_in = newsock;
sock_out = newsock;
pid = getpid();
break;
} else {
- /* Normal production daemon. Fork, and
- have the child process the connection.
- The parent continues listening. */
+ /*
+ * Normal production daemon. Fork, and have
+ * the child process the connection. The
+ * parent continues listening.
+ */
if ((pid = fork()) == 0) {
- /* Child. Close the listening
- socket, and start using the
- accepted socket. Reinitialize
- logging (since our pid has
- changed). We break out of the
- loop to handle the connection. */
- close(listen_sock);
+ /*
+ * Child. Close the listening socket, and start using the
+ * accepted socket. Reinitialize logging (since our pid has
+ * changed). We break out of the loop to handle the connection.
+ */
+ close_listen_socks();
sock_in = newsock;
sock_out = newsock;
log_init(av0, options.log_level, options.log_facility, log_stderr);
/* Close the new socket (the child is now taking care of it). */
close(newsock);
+ } /* for (i = 0; i < num_listen_socks; i++) */
+ /* child process check (or debug mode) */
+ if (num_listen_socks < 0)
+ break;
}
}
/* This is the child processing a new connection. */
- /* Disable the key regeneration alarm. We will not regenerate the
- key since we are no longer in a position to give it to anyone.
- We will not restart on SIGHUP since it no longer makes sense. */
+ /*
+ * Disable the key regeneration alarm. We will not regenerate the
+ * key since we are no longer in a position to give it to anyone. We
+ * will not restart on SIGHUP since it no longer makes sense.
+ */
alarm(0);
signal(SIGALRM, SIG_DFL);
signal(SIGHUP, SIG_DFL);
signal(SIGQUIT, SIG_DFL);
signal(SIGCHLD, SIG_DFL);
- /* Set socket options for the connection. We want the socket to
- close as fast as possible without waiting for anything. If the
- connection is not a socket, these will do nothing. */
- /* setsockopt(sock_in, SOL_SOCKET, SO_REUSEADDR, (void *)&on,
- sizeof(on)); */
+ /*
+ * Set socket options for the connection. We want the socket to
+ * close as fast as possible without waiting for anything. If the
+ * connection is not a socket, these will do nothing.
+ */
+ /* setsockopt(sock_in, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); */
linger.l_onoff = 1;
linger.l_linger = 5;
setsockopt(sock_in, SOL_SOCKET, SO_LINGER, (void *) &linger, sizeof(linger));
- /* Register our connection. This turns encryption off because we
- do not have a key. */
+ /*
+ * Register our connection. This turns encryption off because we do
+ * not have a key.
+ */
packet_set_connection(sock_in, sock_out);
remote_port = get_remote_port();
/* Check whether logins are denied from this host. */
#ifdef LIBWRAP
+ /* XXX LIBWRAP noes not know about IPv6 */
{
struct request_info req;
close(sock_out);
refuse(&req);
}
- verbose("Connection from %.500s port %d", eval_client(&req), remote_port);
+/*XXX IPv6 verbose("Connection from %.500s port %d", eval_client(&req), remote_port); */
}
-#else
+#endif /* LIBWRAP */
/* Log the connection. */
verbose("Connection from %.500s port %d", remote_ip, remote_port);
-#endif /* LIBWRAP */
- /* We don\'t want to listen forever unless the other side
- successfully authenticates itself. So we set up an alarm which
- is cleared after successful authentication. A limit of zero
- indicates no limit. Note that we don\'t set the alarm in
- debugging mode; it is just annoying to have the server exit
- just when you are about to discover the bug. */
+ /*
+ * We don\'t want to listen forever unless the other side
+ * successfully authenticates itself. So we set up an alarm which is
+ * cleared after successful authentication. A limit of zero
+ * indicates no limit. Note that we don\'t set the alarm in debugging
+ * mode; it is just annoying to have the server exit just when you
+ * are about to discover the bug.
+ */
signal(SIGALRM, grace_alarm_handler);
if (!debug_flag)
alarm(options.login_grace_time);
/* Send our protocol version identification. */
snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
PROTOCOL_MAJOR, PROTOCOL_MINOR, SSH_VERSION);
- if (write(sock_out, buf, strlen(buf)) != strlen(buf))
- fatal("Could not write ident string to %s.", get_remote_ipaddr());
+ if (atomicio(write, sock_out, buf, strlen(buf)) != strlen(buf)) {
+ log("Could not write ident string to %s.", remote_ip);
+ fatal_cleanup();
+ }
/* Read other side\'s version identification. */
for (i = 0; i < sizeof(buf) - 1; i++) {
- if (read(sock_in, &buf[i], 1) != 1)
- fatal("Did not receive ident string from %s.", get_remote_ipaddr());
+ if (read(sock_in, &buf[i], 1) != 1) {
+ log("Did not receive ident string from %s.", remote_ip);
+ fatal_cleanup();
+ }
if (buf[i] == '\r') {
buf[i] = '\n';
buf[i + 1] = 0;
buf[sizeof(buf) - 1] = 0;
}
- /* Check that the versions match. In future this might accept
- several versions and set appropriate flags to handle them. */
+ /*
+ * Check that the versions match. In future this might accept
+ * several versions and set appropriate flags to handle them.
+ */
if (sscanf(buf, "SSH-%d.%d-%[^\n]\n", &remote_major, &remote_minor,
- remote_version) != 3) {
- const char *s = "Protocol mismatch.\n";
- (void) write(sock_out, s, strlen(s));
+ remote_version) != 3) {
+ char *s = "Protocol mismatch.\n";
+
+ (void) atomicio(write, sock_out, s, strlen(s));
close(sock_in);
close(sock_out);
- fatal("Bad protocol version identification '%.100s' from %s",
- buf, get_remote_ipaddr());
+ log("Bad protocol version identification '%.100s' from %s",
+ buf, remote_ip);
+ fatal_cleanup();
}
debug("Client protocol version %d.%d; client software version %.100s",
remote_major, remote_minor, remote_version);
if (remote_major != PROTOCOL_MAJOR) {
- const char *s = "Protocol major versions differ.\n";
- (void) write(sock_out, s, strlen(s));
+ char *s = "Protocol major versions differ.\n";
+
+ (void) atomicio(write, sock_out, s, strlen(s));
close(sock_in);
close(sock_out);
- fatal("Protocol major versions differ for %s: %d vs. %d",
- get_remote_ipaddr(),
- PROTOCOL_MAJOR, remote_major);
+ log("Protocol major versions differ for %s: %d vs. %d",
+ remote_ip, PROTOCOL_MAJOR, remote_major);
+ fatal_cleanup();
}
/* Check that the client has sufficiently high software version. */
if (remote_major == 1 && remote_minor < 3)
packet_disconnect("Your ssh version is too old and is no longer supported. Please install a newer version.");
if (remote_major == 1 && remote_minor == 3) {
+ /* note that this disables agent-forwarding */
enable_compat13();
- if (strcmp(remote_version, "OpenSSH-1.1") != 0) {
- debug("Agent forwarding disabled, remote version is not compatible.");
- no_agent_forwarding_flag = 1;
- }
}
- /* Check that the connection comes from a privileged port. Rhosts-
- and Rhosts-RSA-Authentication only make sense from priviledged
- programs. Of course, if the intruder has root access on his
- local machine, he can connect from any port. So do not use
- these authentication methods from machines that you do not trust. */
+ /*
+ * Check that the connection comes from a privileged port. Rhosts-
+ * and Rhosts-RSA-Authentication only make sense from priviledged
+ * programs. Of course, if the intruder has root access on his local
+ * machine, he can connect from any port. So do not use these
+ * authentication methods from machines that you do not trust.
+ */
if (remote_port >= IPPORT_RESERVED ||
remote_port < IPPORT_RESERVED / 2) {
options.rhosts_authentication = 0;
options.rhosts_rsa_authentication = 0;
}
+#ifdef KRB4
+ if (!packet_connection_is_ipv4() &&
+ options.kerberos_authentication) {
+ debug("Kerberos Authentication disabled, only available for IPv4.");
+ options.kerberos_authentication = 0;
+ }
+#endif /* KRB4 */
+
packet_set_nonblocking();
- /* Handle the connection. */
- do_connection();
+ /* perform the key exchange */
+ do_ssh_kex();
+
+ /* authenticate user and start session */
+ do_authentication();
#ifdef KRB4
/* Cleanup user's ticket cache file. */
/* The connection has been terminated. */
verbose("Closing connection to %.100s", remote_ip);
-#ifdef HAVE_LIBPAM
- {
- int retval;
-
- if (pamh != NULL) {
- debug("Closing PAM session.");
- retval = pam_close_session((pam_handle_t *)pamh, 0);
-
- debug("Terminating PAM library.");
- if (pam_end((pam_handle_t *)pamh, retval) != PAM_SUCCESS)
- log("Cannot release PAM authentication.");
-
- fatal_remove_cleanup(&pam_cleanup_proc, NULL);
- }
- }
-#endif /* HAVE_LIBPAM */
+#ifdef USE_PAM
+ finish_pam();
+#endif /* USE_PAM */
packet_close();
exit(0);
}
/*
- * Process an incoming connection. Protocol version identifiers have already
- * been exchanged. This sends server key and performs the key exchange.
- * Server and host keys will no longer be needed after this functions.
+ * SSH1 key exchange
*/
void
-do_connection()
+do_ssh_kex()
{
int i, len;
+ int plen, slen;
BIGNUM *session_key_int;
unsigned char session_key[SSH_SESSION_KEY_LENGTH];
- unsigned char check_bytes[8];
- char *user;
+ unsigned char cookie[8];
unsigned int cipher_type, auth_mask, protocol_flags;
- int plen, slen;
u_int32_t rand = 0;
- /* Generate check bytes that the client must send back in the user
- packet in order for it to be accepted; this is used to defy ip
- spoofing attacks. Note that this only works against somebody
- doing IP spoofing from a remote machine; any machine on the
- local network can still see outgoing packets and catch the
- random cookie. This only affects rhosts authentication, and
- this is one of the reasons why it is inherently insecure. */
+ /*
+ * Generate check bytes that the client must send back in the user
+ * packet in order for it to be accepted; this is used to defy ip
+ * spoofing attacks. Note that this only works against somebody
+ * doing IP spoofing from a remote machine; any machine on the local
+ * network can still see outgoing packets and catch the random
+ * cookie. This only affects rhosts authentication, and this is one
+ * of the reasons why it is inherently insecure.
+ */
for (i = 0; i < 8; i++) {
if (i % 4 == 0)
rand = arc4random();
- check_bytes[i] = rand & 0xff;
+ cookie[i] = rand & 0xff;
rand >>= 8;
}
- /* Send our public key. We include in the packet 64 bits of
- random data that must be matched in the reply in order to
- prevent IP spoofing. */
+ /*
+ * Send our public key. We include in the packet 64 bits of random
+ * data that must be matched in the reply in order to prevent IP
+ * spoofing.
+ */
packet_start(SSH_SMSG_PUBLIC_KEY);
for (i = 0; i < 8; i++)
- packet_put_char(check_bytes[i]);
+ packet_put_char(cookie[i]);
/* Store our public server RSA key. */
packet_put_int(BN_num_bits(public_key->n));
/* Read clients reply (cipher type and session key). */
packet_read_expect(&plen, SSH_CMSG_SESSION_KEY);
- /* Get cipher type. */
+ /* Get cipher type and check whether we accept this. */
cipher_type = packet_get_char();
+ if (!(cipher_mask() & (1 << cipher_type)))
+ packet_disconnect("Warning: client selects unsupported cipher.");
+
/* Get check bytes from the packet. These must match those we
sent earlier with the public key packet. */
for (i = 0; i < 8; i++)
- if (check_bytes[i] != packet_get_char())
+ if (cookie[i] != packet_get_char())
packet_disconnect("IP Spoofing check bytes do not match.");
debug("Encryption type: %.200s", cipher_name(cipher_type));
session_key_int = BN_new();
packet_get_bignum(session_key_int, &slen);
- /* Get protocol flags. */
protocol_flags = packet_get_int();
packet_set_protocol_flags(protocol_flags);
packet_integrity_check(plen, 1 + 8 + slen + 4, SSH_CMSG_SESSION_KEY);
- /* Decrypt it using our private server key and private host key
- (key with larger modulus first). */
+ /*
+ * Decrypt it using our private server key and private host key (key
+ * with larger modulus first).
+ */
if (BN_cmp(sensitive_data.private_key->n, sensitive_data.host_key->n) > 0) {
/* Private key has bigger modulus. */
if (BN_num_bits(sensitive_data.private_key->n) <
sensitive_data.private_key);
}
- /* Compute session id for this session. */
- compute_session_id(session_id, check_bytes,
+ compute_session_id(session_id, cookie,
sensitive_data.host_key->n,
sensitive_data.private_key->n);
- /* Extract session key from the decrypted integer. The key is in
- the least significant 256 bits of the integer; the first byte
- of the key is in the highest bits. */
+ /* Destroy the private and public keys. They will no longer be needed. */
+ RSA_free(public_key);
+ RSA_free(sensitive_data.private_key);
+ RSA_free(sensitive_data.host_key);
+
+ /*
+ * Extract session key from the decrypted integer. The key is in the
+ * least significant 256 bits of the integer; the first byte of the
+ * key is in the highest bits.
+ */
BN_mask_bits(session_key_int, sizeof(session_key) * 8);
len = BN_num_bytes(session_key_int);
if (len < 0 || len > sizeof(session_key))
memset(session_key, 0, sizeof(session_key));
BN_bn2bin(session_key_int, session_key + sizeof(session_key) - len);
+ /* Destroy the decrypted integer. It is no longer needed. */
+ BN_clear_free(session_key_int);
+
/* Xor the first 16 bytes of the session key with the session id. */
for (i = 0; i < 16; i++)
session_key[i] ^= session_id[i];
- /* Destroy the decrypted integer. It is no longer needed. */
- BN_clear_free(session_key_int);
-
/* Set the session key. From this on all communications will be encrypted. */
packet_set_encryption_key(session_key, SSH_SESSION_KEY_LENGTH, cipher_type);
packet_start(SSH_SMSG_SUCCESS);
packet_send();
packet_write_wait();
-
- /* Get the name of the user that we wish to log in as. */
- packet_read_expect(&plen, SSH_CMSG_USER);
-
- /* Get the user name. */
- {
- int ulen;
- user = packet_get_string(&ulen);
- packet_integrity_check(plen, (4 + ulen), SSH_CMSG_USER);
- }
-
- /* Destroy the private and public keys. They will no longer be needed. */
- RSA_free(public_key);
- RSA_free(sensitive_data.private_key);
- RSA_free(sensitive_data.host_key);
-
- setproctitle("%s", user);
- /* Do the authentication. */
- do_authentication(user);
}
+
/*
* Check if the user is allowed to log in via ssh. If user is listed in
* DenyUsers or user's primary group is listed in DenyGroups, false will
{
struct group *grp;
int i;
+#ifdef WITH_AIXAUTHENTICATE
+ char *loginmsg;
+#endif /* WITH_AIXAUTHENTICATE */
/* Shouldn't be called if pw is NULL, but better safe than sorry... */
if (!pw)
if (match_pattern(pw->pw_name, options.deny_users[i]))
return 0;
}
- /* Return false if AllowUsers isn't empty and user isn't listed
- there */
+ /* Return false if AllowUsers isn't empty and user isn't listed there */
if (options.num_allow_users > 0) {
if (!pw->pw_name)
return 0;
if (match_pattern(grp->gr_name, options.deny_groups[i]))
return 0;
}
- /* Return false if AllowGroups isn't empty and user's
- group isn't listed there */
+ /*
+ * Return false if AllowGroups isn't empty and user's group
+ * isn't listed there
+ */
if (options.num_allow_groups > 0) {
if (!grp->gr_name)
return 0;
return 0;
}
}
+
+#ifdef WITH_AIXAUTHENTICATE
+ if (loginrestrictions(pw->pw_name,S_LOGIN,NULL,&loginmsg) != 0)
+ return 0;
+#endif /* WITH_AIXAUTHENTICATE */
+
/* We found no reason not to let this user try to log on... */
return 1;
}
/*
* Performs authentication of an incoming connection. Session key has already
- * been exchanged and encryption is enabled. User is the user name to log
- * in as (received from the client).
+ * been exchanged and encryption is enabled.
*/
void
-do_authentication(char *user)
+do_authentication()
{
struct passwd *pw, pwcopy;
+ int plen, ulen;
+ char *user;
+
+ /* Get the name of the user that we wish to log in as. */
+ packet_read_expect(&plen, SSH_CMSG_USER);
+
+ /* Get the user name. */
+ user = packet_get_string(&ulen);
+ packet_integrity_check(plen, (4 + ulen), SSH_CMSG_USER);
+
+ setproctitle("%s", user);
+
+#ifdef WITH_AIXAUTHENTICATE
+ char *loginmsg;
+#endif /* WITH_AIXAUTHENTICATE */
#ifdef AFS
/* If machine has AFS, set process authentication group. */
pwcopy.pw_shell = xstrdup(pw->pw_shell);
pw = &pwcopy;
-#ifdef HAVE_LIBPAM
- {
- int pam_retval;
-
- debug("Starting up PAM with username \"%.200s\"", pw->pw_name);
-
- pam_retval = pam_start("sshd", pw->pw_name, &conv, (pam_handle_t**)&pamh);
- if (pam_retval != PAM_SUCCESS)
- fatal("PAM initialisation failed: %.200s", PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
-
- fatal_add_cleanup(&pam_cleanup_proc, NULL);
- }
+#ifdef USE_PAM
+ start_pam(pw);
#endif
- /* If we are not running as root, the user must have the same uid
- as the server. */
+ /*
+ * If we are not running as root, the user must have the same uid as
+ * the server.
+ */
if (getuid() != 0 && pw->pw_uid != getuid())
packet_disconnect("Cannot change user when server not running as root.");
#ifdef KRB4
(!options.kerberos_authentication || options.kerberos_or_local_passwd) &&
#endif /* KRB4 */
+#ifdef USE_PAM
+ auth_pam_password(pw, "")) {
+#else /* USE_PAM */
auth_password(pw, "")) {
+#endif /* USE_PAM */
/* Authentication with empty password succeeded. */
log("Login for user %s from %.100s, accepted without authentication.",
pw->pw_name, get_remote_ipaddr());
get_canonical_hostname());
}
/* The user has been authenticated and accepted. */
+#ifdef WITH_AIXAUTHENTICATE
+ loginsuccess(user,get_canonical_hostname(),"ssh",&loginmsg);
+#endif /* WITH_AIXAUTHENTICATE */
packet_start(SSH_SMSG_SUCCESS);
packet_send();
packet_write_wait();
int plen, dlen, nlen, ulen, elen;
int type = 0;
void (*authlog) (const char *fmt,...) = verbose;
-#ifdef HAVE_LIBPAM
- int pam_retval;
-#endif /* HAVE_LIBPAM */
/* Indicate that authentication is needed. */
packet_start(SSH_SMSG_FAILURE);
verbose("Rhosts authentication disabled.");
break;
}
- /* Get client user name. Note that we just have
- to trust the client; this is one reason why
- rhosts authentication is insecure. (Another is
- IP-spoofing on a local network.) */
+ /*
+ * Get client user name. Note that we just have to
+ * trust the client; this is one reason why rhosts
+ * authentication is insecure. (Another is
+ * IP-spoofing on a local network.)
+ */
client_user = packet_get_string(&ulen);
packet_integrity_check(plen, 4 + ulen, type);
authenticated = auth_rhosts(pw, client_user);
snprintf(user, sizeof user, " ruser %s", client_user);
-#ifndef HAVE_LIBPAM
- xfree(client_user);
-#endif /* HAVE_LIBPAM */
break;
case SSH_CMSG_AUTH_RHOSTS_RSA:
verbose("Rhosts with RSA authentication disabled.");
break;
}
- /* Get client user name. Note that we just have
- to trust the client; root on the client machine
- can claim to be any user. */
+ /*
+ * Get client user name. Note that we just have to
+ * trust the client; root on the client machine can
+ * claim to be any user.
+ */
client_user = packet_get_string(&ulen);
/* Get the client host key. */
BN_clear_free(client_host_key_n);
snprintf(user, sizeof user, " ruser %s", client_user);
-#ifndef HAVE_LIBPAM
- xfree(client_user);
-#endif /* HAVE_LIBPAM */
break;
case SSH_CMSG_AUTH_RSA:
verbose("Password authentication disabled.");
break;
}
- /* Read user password. It is in plain text, but
- was transmitted over the encrypted channel so
- it is not visible to an outside observer. */
+ /*
+ * Read user password. It is in plain text, but was
+ * transmitted over the encrypted channel so it is
+ * not visible to an outside observer.
+ */
password = packet_get_string(&dlen);
packet_integrity_check(plen, 4 + dlen, type);
-#ifdef HAVE_LIBPAM
+#ifdef USE_PAM
/* Do PAM auth with password */
- pampasswd = password;
- pam_retval = pam_authenticate((pam_handle_t *)pamh, 0);
- if (pam_retval == PAM_SUCCESS) {
- log("PAM Password authentication accepted for user \"%.100s\"", pw->pw_name);
- authenticated = 1;
- break;
- }
-
- log("PAM Password authentication for \"%.100s\" failed: %s",
- pw->pw_name, PAM_STRERROR((pam_handle_t *)pamh, pam_retval));
- break;
-#else /* HAVE_LIBPAM */
+ authenticated = auth_pam_password(pw, password);
+#else /* USE_PAM */
/* Try authentication with the password. */
authenticated = auth_password(pw, password);
-
+#endif /* USE_PAM */
memset(password, 0, strlen(password));
xfree(password);
break;
-#endif /* HAVE_LIBPAM */
#ifdef SKEY
case SSH_CMSG_AUTH_TIS:
skeyinfo = skey_fake_keyinfo(pw->pw_name);
}
if (skeyinfo != NULL) {
- /* we send our s/key- in
- tis-challenge messages */
+ /* we send our s/key- in tis-challenge messages */
debug("sending challenge '%s'", skeyinfo);
packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
packet_put_string(skeyinfo, strlen(skeyinfo));
#endif
default:
- /* Any unknown messages will be ignored (and
- failure returned) during authentication. */
+ /*
+ * Any unknown messages will be ignored (and failure
+ * returned) during authentication.
+ */
log("Unknown message during authentication: type %d", type);
break;
}
get_remote_port(),
user);
-#ifdef HAVE_LIBPAM
- do_pam_account_and_session(pw->pw_name, client_user,
- get_canonical_hostname());
+ if (authenticated) {
+#ifdef USE_PAM
+ if (!do_pam_account(pw->pw_name, client_user)) {
+ if (client_user != NULL)
+ xfree(client_user);
- /* Clean up */
- if (client_user != NULL)
- xfree(client_user);
-
- if (password != NULL) {
- memset(password, 0, strlen(password));
- xfree(password);
+ do_fake_authloop(pw->pw_name);
+ }
+#endif /* USE_PAM */
+ return;
}
-#endif /* HAVE_LIBPAM */
- if (authenticated)
- return;
+ if (client_user != NULL) {
+ xfree(client_user);
+ client_user = NULL;
+ }
if (attempt > AUTH_FAIL_MAX)
packet_disconnect(AUTH_FAIL_MSG, pw->pw_name);
packet_send();
packet_write_wait();
- /* Keep reading packets, and always respond with a failure. This
- is to avoid disclosing whether such a user really exists. */
+ /*
+ * Keep reading packets, and always respond with a failure. This is
+ * to avoid disclosing whether such a user really exists.
+ */
for (attempt = 1;; attempt++) {
- /* Read a packet. This will not return if the client
- disconnects. */
+ /* Read a packet. This will not return if the client disconnects. */
int plen;
+#ifndef SKEY
+ (void)packet_read(&plen);
+#else /* SKEY */
int type = packet_read(&plen);
-#ifdef SKEY
int dlen;
char *password, *skeyinfo;
- if (options.password_authentication &&
- options.skey_authentication == 1 &&
- type == SSH_CMSG_AUTH_PASSWORD &&
- (password = packet_get_string(&dlen)) != NULL &&
- dlen == 5 &&
- strncasecmp(password, "s/key", 5) == 0 &&
+ /* Try to send a fake s/key challenge. */
+ if (options.skey_authentication == 1 &&
(skeyinfo = skey_fake_keyinfo(user)) != NULL) {
- /* Send a fake s/key challenge. */
- packet_send_debug(skeyinfo);
+ if (type == SSH_CMSG_AUTH_TIS) {
+ packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
+ packet_put_string(skeyinfo, strlen(skeyinfo));
+ packet_send();
+ packet_write_wait();
+ continue;
+ } else if (type == SSH_CMSG_AUTH_PASSWORD &&
+ options.password_authentication &&
+ (password = packet_get_string(&dlen)) != NULL &&
+ dlen == 5 &&
+ strncasecmp(password, "s/key", 5) == 0 ) {
+ packet_send_debug(skeyinfo);
+ }
}
#endif
if (attempt > AUTH_FAIL_MAX)
packet_disconnect(AUTH_FAIL_MSG, user);
- /* Send failure. This should be indistinguishable from a
- failed authentication. */
+ /*
+ * Send failure. This should be indistinguishable from a
+ * failed authentication.
+ */
packet_start(SSH_SMSG_FAILURE);
packet_send();
packet_write_wait();
+#ifdef WITH_AIXAUTHENTICATE
+ if (strncmp(get_authname(type),"password",
+ strlen(get_authname(type))) == 0)
+ loginfailed(pw->pw_name,get_canonical_hostname(),"ssh");
+#endif /* WITH_AIXAUTHENTICATE */
}
/* NOTREACHED */
abort();
}
}
+struct pty_cleanup_context {
+ const char *ttyname;
+ int pid;
+};
+
+/*
+ * Function to perform cleanup if we get aborted abnormally (e.g., due to a
+ * dropped connection).
+ */
+void
+pty_cleanup_proc(void *context)
+{
+ struct pty_cleanup_context *cu = context;
+
+ debug("pty_cleanup_proc called");
+
+ /* Record that the user has logged out. */
+ record_logout(cu->pid, cu->ttyname);
+
+ /* Release the pseudo-tty. */
+ pty_release(cu->ttyname);
+}
+
+/* simple cleanup: chown tty slave back to root */
+static void
+pty_release_proc(void *tty)
+{
+ char *ttyname = tty;
+ pty_release(ttyname);
+}
+
/*
* Prepares for an interactive session. This is called after the user has
* been successfully authenticated. During this message exchange, pseudo
int have_pty = 0, ptyfd = -1, ttyfd = -1, xauthfd = -1;
int row, col, xpixel, ypixel, screen;
char ttyname[64];
- char *command, *term = NULL, *display = NULL, *proto = NULL,
- *data = NULL;
- struct group *grp;
- gid_t tty_gid;
- mode_t tty_mode;
+ char *command, *term = NULL, *display = NULL, *proto = NULL, *data = NULL;
int n_bytes;
- /* Cancel the alarm we set to limit the time taken for
- authentication. */
+ /*
+ * Cancel the alarm we set to limit the time taken for
+ * authentication.
+ */
alarm(0);
- /* Inform the channel mechanism that we are the server side and
- that the client may request to connect to any port at all.
- (The user could do it anyway, and we wouldn\'t know what is
- permitted except by the client telling us, so we can equally
- well trust the client not to request anything bogus.) */
+ /*
+ * Inform the channel mechanism that we are the server side and that
+ * the client may request to connect to any port at all. (The user
+ * could do it anyway, and we wouldn\'t know what is permitted except
+ * by the client telling us, so we can equally well trust the client
+ * not to request anything bogus.)
+ */
channel_permit_all_opens();
- /* We stay in this loop until the client requests to execute a
- shell or a command. */
+ /*
+ * We stay in this loop until the client requests to execute a shell
+ * or a command.
+ */
while (1) {
int plen, dlen;
debug("Allocating pty.");
/* Allocate a pty and open it. */
- if (!pty_allocate(&ptyfd, &ttyfd, ttyname)) {
+ if (!pty_allocate(&ptyfd, &ttyfd, ttyname,
+ sizeof(ttyname))) {
error("Failed to allocate pty.");
goto fail;
}
- /* Determine the group to make the owner of the tty. */
- grp = getgrnam("tty");
- if (grp) {
- tty_gid = grp->gr_gid;
- tty_mode = S_IRUSR | S_IWUSR | S_IWGRP;
- } else {
- tty_gid = pw->pw_gid;
- tty_mode = S_IRUSR | S_IWUSR | S_IWGRP | S_IWOTH;
- }
-
- /* Change ownership of the tty. */
- if (chown(ttyname, pw->pw_uid, tty_gid) < 0)
- fatal("chown(%.100s, %d, %d) failed: %.100s",
- ttyname, pw->pw_uid, tty_gid, strerror(errno));
- if (chmod(ttyname, tty_mode) < 0)
- fatal("chmod(%.100s, 0%o) failed: %.100s",
- ttyname, tty_mode, strerror(errno));
+ fatal_add_cleanup(pty_release_proc, (void *)ttyname);
+ pty_setowner(pw, ttyname);
/* Get TERM from the packet. Note that the value may be of arbitrary length. */
term = packet_get_string(&dlen);
packet_integrity_check(dlen, strlen(term), type);
- /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */
+
/* Remaining bytes */
n_bytes = plen - (4 + dlen + 4 * 4);
- if (strcmp(term, "") == 0)
+ if (strcmp(term, "") == 0) {
+ xfree(term);
term = NULL;
+ }
/* Get window size from the packet. */
row = packet_get_int();
screen = packet_get_int();
else
screen = 0;
- display = x11_create_display_inet(screen);
+ display = x11_create_display_inet(screen, options.x11_display_offset);
if (!display)
goto fail;
#endif /* XAUTH_PATH */
case SSH_CMSG_AGENT_REQUEST_FORWARDING:
- if (no_agent_forwarding_flag) {
+ if (no_agent_forwarding_flag || compat13) {
debug("Authentication agent forwarding not permitted for this authentication.");
goto fail;
}
return;
default:
- /* Any unknown messages in this phase are ignored,
- and a failure message is returned. */
+ /*
+ * Any unknown messages in this phase are ignored,
+ * and a failure message is returned.
+ */
log("Unknown packet type received after authentication: %d", type);
goto fail;
}
continue;
do_forced_command:
- /* There is a forced command specified for this login.
- Execute it. */
+ /*
+ * There is a forced command specified for this login.
+ * Execute it.
+ */
debug("Executing forced command: %.900s", forced_command);
if (have_pty)
do_exec_pty(forced_command, ptyfd, ttyfd, ttyname, pw, term, display, proto, data);
setproctitle("%s@notty", pw->pw_name);
+#ifdef USE_PAM
+ do_pam_setcred();
+#endif /* USE_PAM */
+
/* Fork the child. */
if ((pid = fork()) == 0) {
/* Child. Reinitialize the log since the pid has changed. */
log_init(av0, options.log_level, options.log_facility, log_stderr);
- /* Create a new session and process group since the 4.4BSD
- setlogin() affects the entire process group. */
+ /*
+ * Create a new session and process group since the 4.4BSD
+ * setlogin() affects the entire process group.
+ */
if (setsid() < 0)
error("setsid failed: %.100s", strerror(errno));
#ifdef USE_PIPES
- /* Redirect stdin. We close the parent side of the socket
- pair, and make the child side the standard input. */
+ /*
+ * Redirect stdin. We close the parent side of the socket
+ * pair, and make the child side the standard input.
+ */
close(pin[1]);
if (dup2(pin[0], 0) < 0)
perror("dup2 stdin");
perror("dup2 stderr");
close(perr[1]);
#else /* USE_PIPES */
- /* Redirect stdin, stdout, and stderr. Stdin and stdout
- will use the same socket, as some programs
- (particularly rdist) seem to depend on it. */
+ /*
+ * Redirect stdin, stdout, and stderr. Stdin and stdout will
+ * use the same socket, as some programs (particularly rdist)
+ * seem to depend on it.
+ */
close(inout[1]);
close(err[1]);
if (dup2(inout[0], 0) < 0) /* stdin */
close(inout[0]);
close(err[0]);
- /* Enter the interactive session. Note: server_loop must be able
- to handle the case that fdin and fdout are the same. */
+ /*
+ * Enter the interactive session. Note: server_loop must be able to
+ * handle the case that fdin and fdout are the same.
+ */
server_loop(pid, inout[1], inout[1], err[1]);
/* server_loop has closed inout[1] and err[1]. */
#endif /* USE_PIPES */
}
-struct pty_cleanup_context {
- const char *ttyname;
- int pid;
-};
-
-/*
- * Function to perform cleanup if we get aborted abnormally (e.g., due to a
- * dropped connection).
- */
-void
-pty_cleanup_proc(void *context)
-{
- struct pty_cleanup_context *cu = context;
-
- debug("pty_cleanup_proc called");
-
- /* Record that the user has logged out. */
- record_logout(cu->pid, cu->ttyname);
-
- /* Release the pseudo-tty. */
- pty_release(cu->ttyname);
-}
-
/*
* This is called to fork and execute a command when we have a tty. This
* will call do_child from the child, and server_loop from the parent after
char line[256];
struct stat st;
int quiet_login;
- struct sockaddr_in from;
- int fromlen;
+ struct sockaddr_storage from;
+ socklen_t fromlen;
struct pty_cleanup_context cleanup_context;
/* Get remote host name. */
hostname = get_canonical_hostname();
- /* Get the time when the user last logged in. Buf will be set to
- contain the hostname the last login was from. */
+ /*
+ * Get the time when the user last logged in. Buf will be set to
+ * contain the hostname the last login was from.
+ */
if (!options.use_login) {
last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
buf, sizeof(buf));
}
setproctitle("%s@%s", pw->pw_name, strrchr(ttyname, '/') + 1);
+#ifdef USE_PAM
+ do_pam_session(pw->pw_name, ttyname);
+ do_pam_setcred();
+#endif /* USE_PAM */
+
/* Fork the child. */
if ((pid = fork()) == 0) {
pid = getpid();
/* Close the extra descriptor for the pseudo tty. */
close(ttyfd);
- /* Get IP address of client. This is needed because we
- want to record where the user logged in from. If the
- connection is not a socket, let the ip address be 0.0.0.0. */
+ /*
+ * Get IP address of client. This is needed because we want
+ * to record where the user logged in from. If the
+ * connection is not a socket, let the ip address be 0.0.0.0.
+ */
memset(&from, 0, sizeof(from));
if (packet_get_connection_in() == packet_get_connection_out()) {
fromlen = sizeof(from);
}
/* Record that there was a login on that terminal. */
record_login(pid, ttyname, pw->pw_name, pw->pw_uid, hostname,
- &from);
+ (struct sockaddr *)&from);
/* Check if .hushlogin exists. */
snprintf(line, sizeof line, "%.200s/.hushlogin", pw->pw_dir);
quiet_login = stat(line, &st) >= 0;
-#ifdef HAVE_LIBPAM
- /* output the results of the pamconv() */
- if (!quiet_login && pamconv_msg != NULL)
- fprintf(stderr, pamconv_msg);
-#endif
-
- /* If the user has logged in before, display the time of
- last login. However, don't display anything extra if a
- command has been specified (so that ssh can be used to
- execute commands on a remote machine without users
- knowing they are going to another machine). Login(1)
- will do this for us as well, so check if login(1) is used */
+#ifdef USE_PAM
+ if (!quiet_login)
+ print_pam_messages();
+#endif /* USE_PAM */
+
+ /*
+ * If the user has logged in before, display the time of last
+ * login. However, don't display anything extra if a command
+ * has been specified (so that ssh can be used to execute
+ * commands on a remote machine without users knowing they
+ * are going to another machine). Login(1) will do this for
+ * us as well, so check if login(1) is used
+ */
if (command == NULL && last_login_time != 0 && !quiet_login &&
!options.use_login) {
/* Convert the date to a string. */
else
printf("Last login: %s from %s\r\n", time_string, buf);
}
- /* Print /etc/motd unless a command was specified or
- printing it was disabled in server options or login(1)
- will be used. Note that some machines appear to print
- it in /etc/profile or similar. */
+ /*
+ * Print /etc/motd unless a command was specified or printing
+ * it was disabled in server options or login(1) will be
+ * used. Note that some machines appear to print it in
+ * /etc/profile or similar.
+ */
if (command == NULL && options.print_motd && !quiet_login &&
!options.use_login) {
/* Print /etc/motd if it exists. */
/* Parent. Close the slave side of the pseudo tty. */
close(ttyfd);
- /* Create another descriptor of the pty master side for use as the
- standard input. We could use the original descriptor, but this
- simplifies code in server_loop. The descriptor is bidirectional. */
- fdout = dup(ptyfd);
- if (fdout < 0)
- packet_disconnect("dup failed: %.100s", strerror(errno));
-
- /* Add a cleanup function to clear the utmp entry and record logout
- time in case we call fatal() (e.g., the connection gets closed). */
+ /*
+ * Add a cleanup function to clear the utmp entry and record logout
+ * time in case we call fatal() (e.g., the connection gets closed).
+ */
cleanup_context.pid = pid;
cleanup_context.ttyname = ttyname;
fatal_add_cleanup(pty_cleanup_proc, (void *) &cleanup_context);
+ fatal_remove_cleanup(pty_release_proc, (void *) ttyname);
+
+ /*
+ * Create another descriptor of the pty master side for use as the
+ * standard input. We could use the original descriptor, but this
+ * simplifies code in server_loop. The descriptor is bidirectional.
+ */
+ fdout = dup(ptyfd);
+ if (fdout < 0)
+ packet_disconnect("dup failed: %.100s", strerror(errno));
/* Enter interactive session. */
server_loop(pid, ptyfd, fdout, -1);
/* Release the pseudo-tty. */
pty_release(ttyname);
- /* Close the server side of the socket pairs. We must do this
- after the pty cleanup, so that another process doesn't get this
- pty while we're still cleaning up. */
+ /*
+ * Close the server side of the socket pairs. We must do this after
+ * the pty cleanup, so that another process doesn't get this pty
+ * while we're still cleaning up.
+ */
close(ptyfd);
close(fdout);
}
unsigned int i, namelen;
char **env;
- /* Find the slot where the value should be stored. If the
- variable already exists, we reuse the slot; otherwise we append
- a new slot at the end of the array, expanding if necessary. */
+ /*
+ * Find the slot where the value should be stored. If the variable
+ * already exists, we reuse the slot; otherwise we append a new slot
+ * at the end of the array, expanding if necessary.
+ */
env = *envp;
namelen = strlen(name);
for (i = 0; env[i]; i++)
if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
break;
if (env[i]) {
- /* Name already exists. Reuse the slot. */
+ /* Reuse the slot. */
xfree(env[i]);
} else {
- /* New variable. Expand the array if necessary. */
+ /* New variable. Expand if necessary. */
if (i >= (*envsizep) - 1) {
(*envsizep) += 50;
env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
char buf[4096];
char *cp, *value;
- /* Open the environment file. */
f = fopen(filename, "r");
if (!f)
return;
- /* Process each line. */
while (fgets(buf, sizeof(buf), f)) {
- /* Skip leading whitespace. */
- for (cp = buf; *cp == ' ' || *cp == '\t'; cp++);
-
- /* Ignore empty and comment lines. */
+ for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
+ ;
if (!*cp || *cp == '#' || *cp == '\n')
continue;
-
- /* Remove newline. */
if (strchr(cp, '\n'))
*strchr(cp, '\n') = '\0';
-
- /* Find the equals sign. Its lack indicates badly
- formatted line. */
value = strchr(cp, '=');
if (value == NULL) {
fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
continue;
}
- /* Replace the equals sign by nul, and advance value to
- the value string. */
+ /* Replace the equals sign by nul, and advance value to the value string. */
*value = '\0';
value++;
-
- /* Set the value in environment. */
child_set_env(env, envsize, cp, value);
}
-
fclose(f);
}
+#ifdef USE_PAM
+/*
+ * Sets any environment variables which have been specified by PAM
+ */
+void do_pam_environment(char ***env, int *envsize)
+{
+ char *equals, var_name[512], var_val[512];
+ char **pam_env;
+ int i;
+
+ if ((pam_env = fetch_pam_environment()) == NULL)
+ return;
+
+ for(i = 0; pam_env[i] != NULL; i++) {
+ if ((equals = strstr(pam_env[i], "=")) == NULL)
+ continue;
+
+ if (strlen(pam_env[i]) < (sizeof(var_name) - 1))
+ {
+ memset(var_name, '\0', sizeof(var_name));
+ memset(var_val, '\0', sizeof(var_val));
+
+ strncpy(var_name, pam_env[i], equals - pam_env[i]);
+ strcpy(var_val, equals + 1);
+
+ debug("PAM environment: %s=%s", var_name, var_val);
+
+ child_set_env(env, envsize, var_name, var_val);
+ }
+ }
+}
+#endif /* USE_PAM */
+
/*
* Performs common processing for the child, such as setting up the
* environment, closing extra file descriptors, setting the user and group
struct stat st;
char *argv[10];
-#ifndef HAVE_LIBPAM /* pam_nologin handles this */
+#ifndef USE_PAM /* pam_nologin handles this */
/* Check /etc/nologin. */
f = fopen("/etc/nologin", "r");
if (f) {
if (pw->pw_uid != 0)
exit(254);
}
-#endif /* HAVE_LIBPAM */
+#endif /* USE_PAM */
-#ifdef HAVE_SETLOGIN
/* Set login name in the kernel. */
if (setlogin(pw->pw_name) < 0)
error("setlogin failed: %s", strerror(errno));
-#endif /* HAVE_SETLOGIN */
/* Set uid, gid, and groups. */
/* Login(1) does this as well, and it needs uid 0 for the "-h"
if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
fatal("Failed to set uids to %d.", (int) pw->pw_uid);
}
- /* Get the shell from the password data. An empty shell field is
- legal, and means /bin/sh. */
+ /*
+ * Get the shell from the password data. An empty shell field is
+ * legal, and means /bin/sh.
+ */
shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
#ifdef AFS
}
#endif /* AFS */
- /* Initialize the environment. In the first part we allocate
- space for all environment variables. */
+ /* Initialize the environment. */
envsize = 100;
env = xmalloc(envsize * sizeof(char *));
env[0] = NULL;
/* Normal systems set SHELL by default. */
child_set_env(&env, &envsize, "SHELL", shell);
}
- /* Let it inherit timezone if we have one. */
if (getenv("TZ"))
child_set_env(&env, &envsize, "TZ", getenv("TZ"));
xfree(ce);
}
- /* Set SSH_CLIENT. */
snprintf(buf, sizeof buf, "%.50s %d %d",
- get_remote_ipaddr(), get_remote_port(), options.port);
+ get_remote_ipaddr(), get_remote_port(), get_local_port());
child_set_env(&env, &envsize, "SSH_CLIENT", buf);
- /* Set SSH_TTY if we have a pty. */
if (ttyname)
child_set_env(&env, &envsize, "SSH_TTY", ttyname);
-
- /* Set TERM if we have a pty. */
if (term)
child_set_env(&env, &envsize, "TERM", term);
-
- /* Set DISPLAY if we have one. */
if (display)
child_set_env(&env, &envsize, "DISPLAY", display);
+#ifdef _AIX
+ {
+ char *authstate,*krb5cc;
+
+ if ((authstate = getenv("AUTHSTATE")) != NULL)
+ child_set_env(&env,&envsize,"AUTHSTATE",authstate);
+
+ if ((krb5cc = getenv("KRB5CCNAME")) != NULL)
+ child_set_env(&env,&envsize,"KRB5CCNAME",krb5cc);
+ }
+#endif
+
#ifdef KRB4
{
extern char *ticket;
}
#endif /* KRB4 */
-#ifdef HAVE_LIBPAM
+#ifdef USE_PAM
/* Pull in any environment variables that may have been set by PAM. */
- {
- char *equals, var_name[512], var_val[512];
- char **pam_env = pam_getenvlist((pam_handle_t *)pamh);
- int i;
- for(i = 0; pam_env && pam_env[i]; i++) {
- equals = strstr(pam_env[i], "=");
- if ((strlen(pam_env[i]) < (sizeof(var_name) - 1)) && (equals != NULL))
- {
- memset(var_name, '\0', sizeof(var_name));
- memset(var_val, '\0', sizeof(var_val));
- strncpy(var_name, pam_env[i], equals - pam_env[i]);
- strcpy(var_val, equals + 1);
- child_set_env(&env, &envsize, var_name, var_val);
- }
- }
- }
-#endif /* HAVE_LIBPAM */
+ do_pam_environment(&env, &envsize);
+#endif /* USE_PAM */
- /* Set XAUTHORITY to always be a local file. */
if (xauthfile)
child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
- /* Set variable for forwarded authentication connection, if we
- have one. */
if (auth_get_socket_name() != NULL)
child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
auth_get_socket_name());
- /* Read $HOME/.ssh/environment. */
+ read_environment_file(&env,&envsize,"/etc/environment");
+
+ /* read $HOME/.ssh/environment. */
if (!options.use_login) {
snprintf(buf, sizeof buf, "%.200s/.ssh/environment", pw->pw_dir);
read_environment_file(&env, &envsize, buf);
}
- /* If debugging, dump the environment to stderr. */
if (debug_flag) {
+ /* dump the environment */
fprintf(stderr, "Environment:\n");
for (i = 0; env[i]; i++)
fprintf(stderr, " %.200s\n", env[i]);
}
- /* Close the connection descriptors; note that this is the child,
- and the server will still have the socket open, and it is
- important that we do not shutdown it. Note that the
- descriptors cannot be closed before building the environment,
- as we call get_remote_ipaddr there. */
+ /*
+ * Close the connection descriptors; note that this is the child, and
+ * the server will still have the socket open, and it is important
+ * that we do not shutdown it. Note that the descriptors cannot be
+ * closed before building the environment, as we call
+ * get_remote_ipaddr there.
+ */
if (packet_get_connection_in() == packet_get_connection_out())
close(packet_get_connection_in());
else {
close(packet_get_connection_in());
close(packet_get_connection_out());
}
- /* Close all descriptors related to channels. They will still
- remain open in the parent. */
+ /*
+ * Close all descriptors related to channels. They will still remain
+ * open in the parent.
+ */
+ /* XXX better use close-on-exec? -markus */
channel_close_all();
- /* Close any extra file descriptors. Note that there may still be
- descriptors left by system functions. They will be closed
- later. */
+ /*
+ * Close any extra file descriptors. Note that there may still be
+ * descriptors left by system functions. They will be closed later.
+ */
endpwent();
- endhostent();
- /* Close any extra open file descriptors so that we don\'t have
- them hanging around in clients. Note that we want to do this
- after initgroups, because at least on Solaris 2.3 it leaves
- file descriptors open. */
+ /*
+ * Close any extra open file descriptors so that we don\'t have them
+ * hanging around in clients. Note that we want to do this after
+ * initgroups, because at least on Solaris 2.3 it leaves file
+ * descriptors open.
+ */
for (i = 3; i < 64; i++)
close(i);
fprintf(stderr, "Could not chdir to home directory %s: %s\n",
pw->pw_dir, strerror(errno));
- /* Must take new environment into use so that .ssh/rc, /etc/sshrc
- and xauth are run in the proper environment. */
+ /*
+ * Must take new environment into use so that .ssh/rc, /etc/sshrc and
+ * xauth are run in the proper environment.
+ */
environ = env;
- /* Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found
- first in this order). */
+ /*
+ * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
+ * in this order).
+ */
if (!options.use_login) {
if (stat(SSH_USER_RC, &st) >= 0) {
if (debug_flag)
}
#ifdef XAUTH_PATH
else {
- /* Add authority data to .Xauthority if
- appropriate. */
+ /* Add authority data to .Xauthority if appropriate. */
if (auth_proto != NULL && auth_data != NULL) {
if (debug_flag)
fprintf(stderr, "Running %.100s add %.100s %.100s %.100s\n",
else
cp = shell;
}
- /* If we have no command, execute the shell. In this case, the
- shell name to be passed in argv[0] is preceded by '-' to
- indicate that this is a login shell. */
+ /*
+ * If we have no command, execute the shell. In this case, the shell
+ * name to be passed in argv[0] is preceded by '-' to indicate that
+ * this is a login shell.
+ */
if (!command) {
if (!options.use_login) {
char buf[256];
- /* Check for mail if we have a tty and it was
- enabled in server options. */
+ /*
+ * Check for mail if we have a tty and it was enabled
+ * in server options.
+ */
if (ttyname && options.check_mail) {
char *mailbox;
struct stat mailstat;
exit(1);
}
}
- /* Execute the command using the user's shell. This uses the -c
- option to execute the command. */
+ /*
+ * Execute the command using the user's shell. This uses the -c
+ * option to execute the command.
+ */
argv[0] = (char *) cp;
argv[1] = "-c";
argv[2] = (char *) command;
andersk / openssh.git / blobdiff