version 1.163, 2003/08/31 13:29:05 |
version 1.163.2.1, 2004/02/28 03:51:33 |
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#include "session.h" |
#include "session.h" |
#include "monitor_wrap.h" |
#include "monitor_wrap.h" |
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#ifdef KRB5 |
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#include <kafs.h> |
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#endif |
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#ifdef GSSAPI |
#ifdef GSSAPI |
#include "ssh-gss.h" |
#include "ssh-gss.h" |
#endif |
#endif |
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Session *session_new(void); |
Session *session_new(void); |
void session_set_fds(Session *, int, int, int); |
void session_set_fds(Session *, int, int, int); |
void session_pty_cleanup(void *); |
void session_pty_cleanup(Session *); |
void session_proctitle(Session *); |
void session_proctitle(Session *); |
int session_setup_x11fwd(Session *); |
int session_setup_x11fwd(Session *); |
void do_exec_pty(Session *, const char *); |
void do_exec_pty(Session *, const char *); |
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login_cap_t *lc; |
login_cap_t *lc; |
#endif |
#endif |
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static int is_child = 0; |
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/* Name and directory of socket for authentication agent forwarding. */ |
/* Name and directory of socket for authentication agent forwarding. */ |
static char *auth_sock_name = NULL; |
static char *auth_sock_name = NULL; |
static char *auth_sock_dir = NULL; |
static char *auth_sock_dir = NULL; |
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/* removes the agent forwarding socket */ |
/* removes the agent forwarding socket */ |
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static void |
static void |
auth_sock_cleanup_proc(void *_pw) |
auth_sock_cleanup_proc(struct passwd *pw) |
{ |
{ |
struct passwd *pw = _pw; |
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if (auth_sock_name != NULL) { |
if (auth_sock_name != NULL) { |
temporarily_use_uid(pw); |
temporarily_use_uid(pw); |
unlink(auth_sock_name); |
unlink(auth_sock_name); |
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/* Allocate a buffer for the socket name, and format the name. */ |
/* Allocate a buffer for the socket name, and format the name. */ |
auth_sock_name = xmalloc(MAXPATHLEN); |
auth_sock_name = xmalloc(MAXPATHLEN); |
auth_sock_dir = xmalloc(MAXPATHLEN); |
auth_sock_dir = xmalloc(MAXPATHLEN); |
strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXX", MAXPATHLEN); |
strlcpy(auth_sock_dir, "/tmp/ssh-XXXXXXXXXX", MAXPATHLEN); |
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/* Create private directory for socket */ |
/* Create private directory for socket */ |
if (mkdtemp(auth_sock_dir) == NULL) { |
if (mkdtemp(auth_sock_dir) == NULL) { |
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snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld", |
snprintf(auth_sock_name, MAXPATHLEN, "%s/agent.%ld", |
auth_sock_dir, (long) getpid()); |
auth_sock_dir, (long) getpid()); |
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/* delete agent socket on fatal() */ |
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fatal_add_cleanup(auth_sock_cleanup_proc, pw); |
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/* Create the socket. */ |
/* Create the socket. */ |
sock = socket(AF_UNIX, SOCK_STREAM, 0); |
sock = socket(AF_UNIX, SOCK_STREAM, 0); |
if (sock < 0) |
if (sock < 0) |
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restore_uid(); |
restore_uid(); |
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/* Start listening on the socket. */ |
/* Start listening on the socket. */ |
if (listen(sock, 5) < 0) |
if (listen(sock, SSH_LISTEN_BACKLOG) < 0) |
packet_disconnect("listen: %.100s", strerror(errno)); |
packet_disconnect("listen: %.100s", strerror(errno)); |
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/* Allocate a channel for the authentication agent socket. */ |
/* Allocate a channel for the authentication agent socket. */ |
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else |
else |
do_authenticated1(authctxt); |
do_authenticated1(authctxt); |
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/* remove agent socket */ |
do_cleanup(authctxt); |
if (auth_sock_name != NULL) |
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auth_sock_cleanup_proc(authctxt->pw); |
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#ifdef KRB5 |
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if (options.kerberos_ticket_cleanup) |
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krb5_cleanup_proc(authctxt); |
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#endif |
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} |
} |
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/* |
/* |
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/* Fork the child. */ |
/* Fork the child. */ |
if ((pid = fork()) == 0) { |
if ((pid = fork()) == 0) { |
fatal_remove_all_cleanups(); |
is_child = 1; |
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/* Child. Reinitialize the log since the pid has changed. */ |
/* Child. Reinitialize the log since the pid has changed. */ |
log_init(__progname, options.log_level, options.log_facility, log_stderr); |
log_init(__progname, options.log_level, options.log_facility, log_stderr); |
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/* Fork the child. */ |
/* Fork the child. */ |
if ((pid = fork()) == 0) { |
if ((pid = fork()) == 0) { |
fatal_remove_all_cleanups(); |
is_child = 1; |
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/* Child. Reinitialize the log because the pid has changed. */ |
/* Child. Reinitialize the log because the pid has changed. */ |
log_init(__progname, options.log_level, options.log_facility, log_stderr); |
log_init(__progname, options.log_level, options.log_facility, log_stderr); |
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if (getpeername(packet_get_connection_in(), |
if (getpeername(packet_get_connection_in(), |
(struct sockaddr *) & from, &fromlen) < 0) { |
(struct sockaddr *) & from, &fromlen) < 0) { |
debug("getpeername: %.100s", strerror(errno)); |
debug("getpeername: %.100s", strerror(errno)); |
fatal_cleanup(); |
cleanup_exit(255); |
} |
} |
} |
} |
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child_set_env(char ***envp, u_int *envsizep, const char *name, |
child_set_env(char ***envp, u_int *envsizep, const char *name, |
const char *value) |
const char *value) |
{ |
{ |
u_int i, namelen; |
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char **env; |
char **env; |
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u_int envsize; |
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u_int i, namelen; |
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/* |
/* |
* Find the slot where the value should be stored. If the variable |
* Find the slot where the value should be stored. If the variable |
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xfree(env[i]); |
xfree(env[i]); |
} else { |
} else { |
/* New variable. Expand if necessary. */ |
/* New variable. Expand if necessary. */ |
if (i >= (*envsizep) - 1) { |
envsize = *envsizep; |
if (*envsizep >= 1000) |
if (i >= envsize - 1) { |
fatal("child_set_env: too many env vars," |
if (envsize >= 1000) |
" skipping: %.100s", name); |
fatal("child_set_env: too many env vars"); |
(*envsizep) += 50; |
envsize += 50; |
env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *)); |
env = (*envp) = xrealloc(env, envsize * sizeof(char *)); |
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*envsizep = envsize; |
} |
} |
/* Need to set the NULL pointer at end of array beyond the new slot. */ |
/* Need to set the NULL pointer at end of array beyond the new slot. */ |
env[i + 1] = NULL; |
env[i + 1] = NULL; |
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env[0] = NULL; |
env[0] = NULL; |
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#ifdef GSSAPI |
#ifdef GSSAPI |
/* Allow any GSSAPI methods that we've used to alter |
/* Allow any GSSAPI methods that we've used to alter |
* the childs environment as they see fit |
* the childs environment as they see fit |
*/ |
*/ |
ssh_gssapi_do_child(&env, &envsize); |
ssh_gssapi_do_child(&env, &envsize); |
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if (debug_flag) { |
if (debug_flag) { |
fprintf(stderr, |
fprintf(stderr, |
"Running %.500s remove %.100s\n", |
"Running %.500s remove %.100s\n", |
options.xauth_location, s->auth_display); |
options.xauth_location, s->auth_display); |
fprintf(stderr, |
fprintf(stderr, |
"%.500s add %.100s %.100s %.100s\n", |
"%.500s add %.100s %.100s %.100s\n", |
options.xauth_location, s->auth_display, |
options.xauth_location, s->auth_display, |
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} |
} |
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static void |
static void |
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do_pwchange(Session *s) |
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{ |
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fprintf(stderr, "WARNING: Your password has expired.\n"); |
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if (s->ttyfd != -1) { |
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fprintf(stderr, |
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"You must change your password now and login again!\n"); |
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execl(_PATH_PASSWD_PROG, "passwd", (char *)NULL); |
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perror("passwd"); |
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} else { |
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fprintf(stderr, |
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"Password change required but no TTY available.\n"); |
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} |
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exit(1); |
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} |
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static void |
launch_login(struct passwd *pw, const char *hostname) |
launch_login(struct passwd *pw, const char *hostname) |
{ |
{ |
/* Launch login(1). */ |
/* Launch login(1). */ |
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exit(1); |
exit(1); |
} |
} |
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static void |
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child_close_fds(void) |
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{ |
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int i; |
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if (packet_get_connection_in() == packet_get_connection_out()) |
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close(packet_get_connection_in()); |
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else { |
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close(packet_get_connection_in()); |
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close(packet_get_connection_out()); |
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} |
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/* |
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* Close all descriptors related to channels. They will still remain |
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* open in the parent. |
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*/ |
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/* XXX better use close-on-exec? -markus */ |
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channel_close_all(); |
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/* |
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* Close any extra file descriptors. Note that there may still be |
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* descriptors left by system functions. They will be closed later. |
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*/ |
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endpwent(); |
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/* |
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* Close any extra open file descriptors so that we don\'t have them |
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* hanging around in clients. Note that we want to do this after |
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* initgroups, because at least on Solaris 2.3 it leaves file |
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* descriptors open. |
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*/ |
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for (i = 3; i < 64; i++) |
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close(i); |
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} |
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/* |
/* |
* Performs common processing for the child, such as setting up the |
* Performs common processing for the child, such as setting up the |
* environment, closing extra file descriptors, setting the user and group |
* environment, closing extra file descriptors, setting the user and group |
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char *argv[10]; |
char *argv[10]; |
const char *shell, *shell0, *hostname = NULL; |
const char *shell, *shell0, *hostname = NULL; |
struct passwd *pw = s->pw; |
struct passwd *pw = s->pw; |
u_int i; |
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/* remove hostkey from the child's memory */ |
/* remove hostkey from the child's memory */ |
destroy_sensitive_data(); |
destroy_sensitive_data(); |
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/* Force a password change */ |
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if (s->authctxt->force_pwchange) { |
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do_setusercontext(pw); |
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child_close_fds(); |
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do_pwchange(s); |
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exit(1); |
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} |
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/* login(1) is only called if we execute the login shell */ |
/* login(1) is only called if we execute the login shell */ |
if (options.use_login && command != NULL) |
if (options.use_login && command != NULL) |
options.use_login = 0; |
options.use_login = 0; |
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* closed before building the environment, as we call |
* closed before building the environment, as we call |
* get_remote_ipaddr there. |
* get_remote_ipaddr there. |
*/ |
*/ |
if (packet_get_connection_in() == packet_get_connection_out()) |
child_close_fds(); |
close(packet_get_connection_in()); |
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else { |
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close(packet_get_connection_in()); |
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close(packet_get_connection_out()); |
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} |
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/* |
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* Close all descriptors related to channels. They will still remain |
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* open in the parent. |
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*/ |
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/* XXX better use close-on-exec? -markus */ |
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channel_close_all(); |
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/* |
/* |
* Close any extra file descriptors. Note that there may still be |
* Must take new environment into use so that .ssh/rc, |
* descriptors left by system functions. They will be closed later. |
* /etc/ssh/sshrc and xauth are run in the proper environment. |
*/ |
*/ |
endpwent(); |
environ = env; |
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#ifdef KRB5 |
/* |
/* |
* Close any extra open file descriptors so that we don\'t have them |
* At this point, we check to see if AFS is active and if we have |
* hanging around in clients. Note that we want to do this after |
* a valid Kerberos 5 TGT. If so, it seems like a good idea to see |
* initgroups, because at least on Solaris 2.3 it leaves file |
* if we can (and need to) extend the ticket into an AFS token. If |
* descriptors open. |
* we don't do this, we run into potential problems if the user's |
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* home directory is in AFS and it's not world-readable. |
*/ |
*/ |
for (i = 3; i < 64; i++) |
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close(i); |
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/* |
if (options.kerberos_get_afs_token && k_hasafs() && |
* Must take new environment into use so that .ssh/rc, |
(s->authctxt->krb5_ctx != NULL)) { |
* /etc/ssh/sshrc and xauth are run in the proper environment. |
char cell[64]; |
*/ |
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environ = env; |
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debug("Getting AFS token"); |
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k_setpag(); |
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if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0) |
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krb5_afslog(s->authctxt->krb5_ctx, |
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s->authctxt->krb5_fwd_ccache, cell, NULL); |
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krb5_afslog_home(s->authctxt->krb5_ctx, |
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s->authctxt->krb5_fwd_ccache, NULL, NULL, pw->pw_dir); |
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} |
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#endif |
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/* Change current directory to the user\'s home directory. */ |
/* Change current directory to the user\'s home directory. */ |
if (chdir(pw->pw_dir) < 0) { |
if (chdir(pw->pw_dir) < 0) { |
fprintf(stderr, "Could not chdir to home directory %s: %s\n", |
fprintf(stderr, "Could not chdir to home directory %s: %s\n", |
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} |
} |
s->authctxt = authctxt; |
s->authctxt = authctxt; |
s->pw = authctxt->pw; |
s->pw = authctxt->pw; |
if (s->pw == NULL) |
if (s->pw == NULL || !authctxt->valid) |
fatal("no user for session %d", s->self); |
fatal("no user for session %d", s->self); |
debug("session_open: session %d: link with channel %d", s->self, chanid); |
debug("session_open: session %d: link with channel %d", s->self, chanid); |
s->chanid = chanid; |
s->chanid = chanid; |
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n_bytes = packet_remaining(); |
n_bytes = packet_remaining(); |
tty_parse_modes(s->ttyfd, &n_bytes); |
tty_parse_modes(s->ttyfd, &n_bytes); |
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/* |
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* Add a cleanup function to clear the utmp entry and record logout |
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* time in case we call fatal() (e.g., the connection gets closed). |
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*/ |
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fatal_add_cleanup(session_pty_cleanup, (void *)s); |
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if (!use_privsep) |
if (!use_privsep) |
pty_setowner(s->pw, s->tty); |
pty_setowner(s->pw, s->tty); |
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* (e.g., due to a dropped connection). |
* (e.g., due to a dropped connection). |
*/ |
*/ |
void |
void |
session_pty_cleanup2(void *session) |
session_pty_cleanup2(Session *s) |
{ |
{ |
Session *s = session; |
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if (s == NULL) { |
if (s == NULL) { |
error("session_pty_cleanup: no session"); |
error("session_pty_cleanup: no session"); |
return; |
return; |
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} |
} |
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void |
void |
session_pty_cleanup(void *session) |
session_pty_cleanup(Session *s) |
{ |
{ |
PRIVSEP(session_pty_cleanup2(session)); |
PRIVSEP(session_pty_cleanup2(s)); |
} |
} |
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static char * |
static char * |
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session_close(Session *s) |
session_close(Session *s) |
{ |
{ |
debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
debug("session_close: session %d pid %ld", s->self, (long)s->pid); |
if (s->ttyfd != -1) { |
if (s->ttyfd != -1) |
fatal_remove_cleanup(session_pty_cleanup, (void *)s); |
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session_pty_cleanup(s); |
session_pty_cleanup(s); |
} |
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if (s->term) |
if (s->term) |
xfree(s->term); |
xfree(s->term); |
if (s->display) |
if (s->display) |
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* delay detach of session, but release pty, since |
* delay detach of session, but release pty, since |
* the fd's to the child are already closed |
* the fd's to the child are already closed |
*/ |
*/ |
if (s->ttyfd != -1) { |
if (s->ttyfd != -1) |
fatal_remove_cleanup(session_pty_cleanup, (void *)s); |
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session_pty_cleanup(s); |
session_pty_cleanup(s); |
} |
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return; |
return; |
} |
} |
/* detach by removing callback */ |
/* detach by removing callback */ |
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do_authenticated2(Authctxt *authctxt) |
do_authenticated2(Authctxt *authctxt) |
{ |
{ |
server_loop2(authctxt); |
server_loop2(authctxt); |
#if defined(GSSAPI) |
} |
if (options.gss_cleanup_creds) |
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ssh_gssapi_cleanup_creds(NULL); |
void |
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do_cleanup(Authctxt *authctxt) |
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{ |
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static int called = 0; |
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debug("do_cleanup"); |
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/* no cleanup if we're in the child for login shell */ |
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if (is_child) |
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return; |
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/* avoid double cleanup */ |
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if (called) |
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return; |
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called = 1; |
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if (authctxt == NULL) |
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return; |
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#ifdef KRB5 |
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if (options.kerberos_ticket_cleanup && |
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authctxt->krb5_ctx) |
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krb5_cleanup_proc(authctxt); |
#endif |
#endif |
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#ifdef GSSAPI |
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if (compat20 && options.gss_cleanup_creds) |
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ssh_gssapi_cleanup_creds(); |
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#endif |
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/* remove agent socket */ |
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auth_sock_cleanup_proc(authctxt->pw); |
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/* |
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* Cleanup ptys/utmp only if privsep is disabled, |
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* or if running in monitor. |
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*/ |
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if (!use_privsep || mm_is_monitor()) |
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session_destroy_all(session_pty_cleanup2); |
} |
} |