Put ssh back into the repository
Change-Id: I23324372188fa6ed3f93a32b84365f5df6367590
diff --git a/auth-passwd.c b/auth-passwd.c
new file mode 100644
index 0000000..b1c6ce0
--- /dev/null
+++ b/auth-passwd.c
@@ -0,0 +1,214 @@
+/* $OpenBSD: auth-passwd.c,v 1.43 2007/09/21 08:15:29 djm Exp $ */
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ * All rights reserved
+ * Password authentication. This file contains the functions to check whether
+ * the password is valid for the user.
+ *
+ * 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".
+ *
+ * Copyright (c) 1999 Dug Song. All rights reserved.
+ * Copyright (c) 2000 Markus Friedl. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+
+#include <pwd.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+
+#include "packet.h"
+#include "buffer.h"
+#include "log.h"
+#include "servconf.h"
+#include "key.h"
+#include "hostfile.h"
+#include "auth.h"
+#include "auth-options.h"
+
+extern Buffer loginmsg;
+extern ServerOptions options;
+
+#ifdef HAVE_LOGIN_CAP
+extern login_cap_t *lc;
+#endif
+
+
+#define DAY (24L * 60 * 60) /* 1 day in seconds */
+#define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */
+
+void
+disable_forwarding(void)
+{
+ no_port_forwarding_flag = 1;
+ no_agent_forwarding_flag = 1;
+ no_x11_forwarding_flag = 1;
+}
+
+/*
+ * Tries to authenticate the user using password. Returns true if
+ * authentication succeeds.
+ */
+int
+auth_password(Authctxt *authctxt, const char *password)
+{
+ struct passwd * pw = authctxt->pw;
+ int result, ok = authctxt->valid;
+#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE)
+ static int expire_checked = 0;
+#endif
+
+#ifndef HAVE_CYGWIN
+ if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES)
+ ok = 0;
+#endif
+ if (*password == '\0' && options.permit_empty_passwd == 0)
+ return 0;
+
+#ifdef KRB5
+ if (options.kerberos_authentication == 1) {
+ int ret = auth_krb5_password(authctxt, password);
+ if (ret == 1 || ret == 0)
+ return ret && ok;
+ /* Fall back to ordinary passwd authentication. */
+ }
+#endif
+#ifdef HAVE_CYGWIN
+ {
+ HANDLE hToken = cygwin_logon_user(pw, password);
+
+ if (hToken == INVALID_HANDLE_VALUE)
+ return 0;
+ cygwin_set_impersonation_token(hToken);
+ return ok;
+ }
+#endif
+#ifdef USE_PAM
+ if (options.use_pam)
+ return (sshpam_auth_passwd(authctxt, password) && ok);
+#endif
+#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE)
+ if (!expire_checked) {
+ expire_checked = 1;
+ if (auth_shadow_pwexpired(authctxt))
+ authctxt->force_pwchange = 1;
+ }
+#endif
+ result = sys_auth_passwd(authctxt, password);
+ if (authctxt->force_pwchange)
+ disable_forwarding();
+ return (result && ok);
+}
+
+#ifdef BSD_AUTH
+static void
+warn_expiry(Authctxt *authctxt, auth_session_t *as)
+{
+ char buf[256];
+ quad_t pwtimeleft, actimeleft, daysleft, pwwarntime, acwarntime;
+
+ pwwarntime = acwarntime = TWO_WEEKS;
+
+ pwtimeleft = auth_check_change(as);
+ actimeleft = auth_check_expire(as);
+#ifdef HAVE_LOGIN_CAP
+ if (authctxt->valid) {
+ pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS,
+ TWO_WEEKS);
+ acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS,
+ TWO_WEEKS);
+ }
+#endif
+ if (pwtimeleft != 0 && pwtimeleft < pwwarntime) {
+ daysleft = pwtimeleft / DAY + 1;
+ snprintf(buf, sizeof(buf),
+ "Your password will expire in %lld day%s.\n",
+ daysleft, daysleft == 1 ? "" : "s");
+ buffer_append(&loginmsg, buf, strlen(buf));
+ }
+ if (actimeleft != 0 && actimeleft < acwarntime) {
+ daysleft = actimeleft / DAY + 1;
+ snprintf(buf, sizeof(buf),
+ "Your account will expire in %lld day%s.\n",
+ daysleft, daysleft == 1 ? "" : "s");
+ buffer_append(&loginmsg, buf, strlen(buf));
+ }
+}
+
+int
+sys_auth_passwd(Authctxt *authctxt, const char *password)
+{
+ struct passwd *pw = authctxt->pw;
+ auth_session_t *as;
+ static int expire_checked = 0;
+
+ as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh",
+ (char *)password);
+ if (as == NULL)
+ return (0);
+ if (auth_getstate(as) & AUTH_PWEXPIRED) {
+ auth_close(as);
+ disable_forwarding();
+ authctxt->force_pwchange = 1;
+ return (1);
+ } else {
+ if (!expire_checked) {
+ expire_checked = 1;
+ warn_expiry(authctxt, as);
+ }
+ return (auth_close(as));
+ }
+}
+#elif !defined(CUSTOM_SYS_AUTH_PASSWD)
+int
+sys_auth_passwd(Authctxt *authctxt, const char *password)
+{
+ struct passwd *pw = authctxt->pw;
+ char *encrypted_password;
+
+ /* Just use the supplied fake password if authctxt is invalid */
+ char *pw_password = authctxt->valid ? shadow_pw(pw) : pw->pw_passwd;
+
+ /* Check for users with no password. */
+ if (strcmp(pw_password, "") == 0 && strcmp(password, "") == 0)
+ return (1);
+
+ /* Encrypt the candidate password using the proper salt. */
+ encrypted_password = xcrypt(password,
+ (pw_password[0] && pw_password[1]) ? pw_password : "xx");
+
+ /*
+ * Authentication is accepted if the encrypted passwords
+ * are identical.
+ */
+ return (strcmp(encrypted_password, pw_password) == 0);
+}
+#endif