#include "monitor_wrap.h"
#include "msg.h"
#include "packet.h"
-#include "readpass.h"
+#include "misc.h"
#include "servconf.h"
#include "ssh2.h"
#include "xmalloc.h"
extern ServerOptions options;
extern Buffer loginmsg;
extern int compat20;
+extern u_int utmp_len;
#ifdef USE_POSIX_THREADS
#include <pthread.h>
static void
sshpam_sigchld_handler(int sig)
{
+ signal(SIGCHLD, SIG_DFL);
if (cleanup_ctxt == NULL)
return; /* handler called after PAM cleanup, shouldn't happen */
- if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0) == -1)
- return; /* couldn't wait for process */
+ if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, WNOHANG)
+ == -1) {
+ /* PAM thread has not exitted, privsep slave must have */
+ kill(cleanup_ctxt->pam_thread, SIGTERM);
+ if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0)
+ == -1)
+ return; /* could not wait */
+ }
if (WIFSIGNALED(sshpam_thread_status) &&
WTERMSIG(sshpam_thread_status) == SIGTERM)
return; /* terminated by pthread_cancel */
static int sshpam_cred_established = 0;
static int sshpam_account_status = -1;
static char **sshpam_env = NULL;
-static Authctxt *the_authctxt = NULL;
+static Authctxt *sshpam_authctxt = NULL;
+static const char *sshpam_password = NULL;
/* Some PAM implementations don't implement this */
#ifndef HAVE_PAM_GETENVLIST
pam_password_change_required(int reqd)
{
debug3("%s %d", __func__, reqd);
- if (the_authctxt == NULL)
+ if (sshpam_authctxt == NULL)
fatal("%s: PAM authctxt not initialized", __func__);
- the_authctxt->force_pwchange = reqd;
+ sshpam_authctxt->force_pwchange = reqd;
if (reqd) {
no_port_forwarding_flag |= 2;
no_agent_forwarding_flag |= 2;
sshpam_conv.conv = sshpam_thread_conv;
sshpam_conv.appdata_ptr = ctxt;
- if (the_authctxt == NULL)
+ if (sshpam_authctxt == NULL)
fatal("%s: PAM authctxt not initialized", __func__);
buffer_init(&buffer);
if (compat20) {
if (!do_pam_account())
goto auth_fail;
- if (the_authctxt->force_pwchange) {
+ if (sshpam_authctxt->force_pwchange) {
sshpam_err = pam_chauthtok(sshpam_handle,
PAM_CHANGE_EXPIRED_AUTHTOK);
if (sshpam_err != PAM_SUCCESS)
#ifndef USE_POSIX_THREADS
/* Export variables set by do_pam_account */
buffer_put_int(&buffer, sshpam_account_status);
- buffer_put_int(&buffer, the_authctxt->force_pwchange);
+ buffer_put_int(&buffer, sshpam_authctxt->force_pwchange);
/* Export any environment strings set in child */
for(i = 0; environ[i] != NULL; i++)
static int
sshpam_init(Authctxt *authctxt)
{
- extern u_int utmp_len;
extern char *__progname;
const char *pam_rhost, *pam_user, *user = authctxt->user;
debug("PAM: initializing for \"%s\"", user);
sshpam_err =
pam_start(SSHD_PAM_SERVICE, user, &null_conv, &sshpam_handle);
- the_authctxt = authctxt;
+ sshpam_authctxt = authctxt;
if (sshpam_err != PAM_SUCCESS) {
pam_end(sshpam_handle, sshpam_err);
xfree(msg);
return (0);
}
- error("PAM: %s", msg);
+ error("PAM: %s for %s%.100s from %.100s", msg,
+ sshpam_authctxt->valid ? "" : "illegal user ",
+ sshpam_authctxt->user,
+ get_remote_name_or_ip(utmp_len, options.use_dns));
/* FALLTHROUGH */
default:
*num = 0;
xfree(env);
}
+/*
+ * "Blind" conversation function for password authentication. Assumes that
+ * echo-off prompts are for the password and stores messages for later
+ * display.
+ */
+static int
+sshpam_passwd_conv(int n, const struct pam_message **msg,
+ struct pam_response **resp, void *data)
+{
+ struct pam_response *reply;
+ int i;
+ size_t len;
+
+ debug3("PAM: %s called with %d messages", __func__, n);
+
+ *resp = NULL;
+
+ if (n <= 0 || n > PAM_MAX_NUM_MSG)
+ return (PAM_CONV_ERR);
+
+ if ((reply = malloc(n * sizeof(*reply))) == NULL)
+ return (PAM_CONV_ERR);
+ memset(reply, 0, n * sizeof(*reply));
+
+ for (i = 0; i < n; ++i) {
+ switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
+ case PAM_PROMPT_ECHO_OFF:
+ if (sshpam_password == NULL)
+ goto fail;
+ reply[i].resp = xstrdup(sshpam_password);
+ reply[i].resp_retcode = PAM_SUCCESS;
+ break;
+ case PAM_ERROR_MSG:
+ case PAM_TEXT_INFO:
+ len = strlen(PAM_MSG_MEMBER(msg, i, msg));
+ if (len > 0) {
+ buffer_append(&loginmsg,
+ PAM_MSG_MEMBER(msg, i, msg), len);
+ buffer_append(&loginmsg, "\n", 1);
+ }
+ reply[i].resp = xstrdup("");
+ reply[i].resp_retcode = PAM_SUCCESS;
+ break;
+ default:
+ goto fail;
+ }
+ }
+ *resp = reply;
+ return (PAM_SUCCESS);
+
+ fail:
+ for(i = 0; i < n; i++) {
+ if (reply[i].resp != NULL)
+ xfree(reply[i].resp);
+ }
+ xfree(reply);
+ return (PAM_CONV_ERR);
+}
+
+static struct pam_conv passwd_conv = { sshpam_passwd_conv, NULL };
+
+/*
+ * Attempt password authentication via PAM
+ */
+int
+sshpam_auth_passwd(Authctxt *authctxt, const char *password)
+{
+ int flags = (options.permit_empty_passwd == 0 ?
+ PAM_DISALLOW_NULL_AUTHTOK : 0);
+ static char badpw[] = "\b\n\r\177INCORRECT";
+
+ if (!options.use_pam || sshpam_handle == NULL)
+ fatal("PAM: %s called when PAM disabled or failed to "
+ "initialise.", __func__);
+
+ sshpam_password = password;
+ sshpam_authctxt = authctxt;
+
+ /*
+ * If the user logging in is invalid, or is root but is not permitted
+ * by PermitRootLogin, use an invalid password to prevent leaking
+ * information via timing (eg if the PAM config has a delay on fail).
+ */
+ if (!authctxt->valid || (authctxt->pw->pw_uid == 0 &&
+ options.permit_root_login != PERMIT_YES))
+ sshpam_password = badpw;
+
+ sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
+ (const void *)&passwd_conv);
+ if (sshpam_err != PAM_SUCCESS)
+ fatal("PAM: %s: failed to set PAM_CONV: %s", __func__,
+ pam_strerror(sshpam_handle, sshpam_err));
+
+ sshpam_err = pam_authenticate(sshpam_handle, flags);
+ sshpam_password = NULL;
+ if (sshpam_err == PAM_SUCCESS && authctxt->valid) {
+ debug("PAM: password authentication accepted for %.100s",
+ authctxt->user);
+ return 1;
+ } else {
+ debug("PAM: password authentication failed for %.100s: %s",
+ authctxt->valid ? authctxt->user : "an illegal user",
+ pam_strerror(sshpam_handle, sshpam_err));
+ return 0;
+ }
+}
#endif /* USE_PAM */
andersk / openssh.git / blobdiff