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-rw-r--r--source4/nsswitch/pam_winbind.c754
1 files changed, 754 insertions, 0 deletions
diff --git a/source4/nsswitch/pam_winbind.c b/source4/nsswitch/pam_winbind.c
new file mode 100644
index 0000000000..123f670366
--- /dev/null
+++ b/source4/nsswitch/pam_winbind.c
@@ -0,0 +1,754 @@
+/* pam_winbind module
+
+ Copyright Andrew Tridgell <tridge@samba.org> 2000
+ Copyright Tim Potter <tpot@samba.org> 2000
+ Copyright Andrew Bartlett <abartlet@samba.org> 2002
+
+ largely based on pam_userdb by Christian Gafton <gafton@redhat.com>
+ also contains large slabs of code from pam_unix by Elliot Lee <sopwith@redhat.com>
+ (see copyright below for full details)
+*/
+
+#include "pam_winbind.h"
+
+/* data tokens */
+
+#define MAX_PASSWD_TRIES 3
+
+/* some syslogging */
+static void _pam_log(int err, const char *format, ...)
+{
+ va_list args;
+
+ va_start(args, format);
+ openlog(MODULE_NAME, LOG_CONS|LOG_PID, LOG_AUTH);
+ vsyslog(err, format, args);
+ va_end(args);
+ closelog();
+}
+
+static int _pam_parse(int argc, const char **argv)
+{
+ int ctrl;
+ /* step through arguments */
+ for (ctrl = 0; argc-- > 0; ++argv) {
+
+ /* generic options */
+
+ if (!strcmp(*argv,"debug"))
+ ctrl |= WINBIND_DEBUG_ARG;
+ else if (!strcasecmp(*argv, "use_authtok"))
+ ctrl |= WINBIND_USE_AUTHTOK_ARG;
+ else if (!strcasecmp(*argv, "use_first_pass"))
+ ctrl |= WINBIND_USE_FIRST_PASS_ARG;
+ else if (!strcasecmp(*argv, "try_first_pass"))
+ ctrl |= WINBIND_TRY_FIRST_PASS_ARG;
+ else if (!strcasecmp(*argv, "unknown_ok"))
+ ctrl |= WINBIND_UNKNOWN_OK_ARG;
+ else {
+ _pam_log(LOG_ERR, "pam_parse: unknown option; %s", *argv);
+ }
+ }
+
+ return ctrl;
+}
+
+/* --- authentication management functions --- */
+
+/* Attempt a conversation */
+
+static int converse(pam_handle_t *pamh, int nargs,
+ struct pam_message **message,
+ struct pam_response **response)
+{
+ int retval;
+ struct pam_conv *conv;
+
+ retval = pam_get_item(pamh, PAM_CONV, (const void **) &conv ) ;
+ if (retval == PAM_SUCCESS) {
+ retval = conv->conv(nargs, (const struct pam_message **)message,
+ response, conv->appdata_ptr);
+ }
+
+ return retval; /* propagate error status */
+}
+
+
+static int _make_remark(pam_handle_t * pamh, int type, const char *text)
+{
+ int retval = PAM_SUCCESS;
+
+ struct pam_message *pmsg[1], msg[1];
+ struct pam_response *resp;
+
+ pmsg[0] = &msg[0];
+ msg[0].msg = text;
+ msg[0].msg_style = type;
+
+ resp = NULL;
+ retval = converse(pamh, 1, pmsg, &resp);
+
+ if (resp) {
+ _pam_drop_reply(resp, 1);
+ }
+ return retval;
+}
+
+static int pam_winbind_request(enum winbindd_cmd req_type,
+ struct winbindd_request *request,
+ struct winbindd_response *response)
+{
+
+ /* Fill in request and send down pipe */
+ init_request(request, req_type);
+
+ if (write_sock(request, sizeof(*request)) == -1) {
+ _pam_log(LOG_ERR, "write to socket failed!");
+ close_sock();
+ return PAM_SERVICE_ERR;
+ }
+
+ /* Wait for reply */
+ if (read_reply(response) == -1) {
+ _pam_log(LOG_ERR, "read from socket failed!");
+ close_sock();
+ return PAM_SERVICE_ERR;
+ }
+
+ /* We are done with the socket - close it and avoid mischeif */
+ close_sock();
+
+ /* Copy reply data from socket */
+ if (response->result != WINBINDD_OK) {
+ if (response->data.auth.pam_error != PAM_SUCCESS) {
+ _pam_log(LOG_ERR, "request failed: %s, PAM error was %d, NT error was %s",
+ response->data.auth.error_string,
+ response->data.auth.pam_error,
+ response->data.auth.nt_status_string);
+ return response->data.auth.pam_error;
+ } else {
+ _pam_log(LOG_ERR, "request failed, but PAM error 0!");
+ return PAM_SERVICE_ERR;
+ }
+ }
+
+ return PAM_SUCCESS;
+}
+
+static int pam_winbind_request_log(enum winbindd_cmd req_type,
+ struct winbindd_request *request,
+ struct winbindd_response *response,
+ int ctrl,
+ const char *user)
+{
+ int retval;
+
+ retval = pam_winbind_request(req_type, request, response);
+
+ switch (retval) {
+ case PAM_AUTH_ERR:
+ /* incorrect password */
+ _pam_log(LOG_WARNING, "user `%s' denied access (incorrect password)", user);
+ return retval;
+ case PAM_ACCT_EXPIRED:
+ /* account expired */
+ _pam_log(LOG_WARNING, "user `%s' account expired", user);
+ return retval;
+ case PAM_AUTHTOK_EXPIRED:
+ /* password expired */
+ _pam_log(LOG_WARNING, "user `%s' password expired", user);
+ return retval;
+ case PAM_NEW_AUTHTOK_REQD:
+ /* password expired */
+ _pam_log(LOG_WARNING, "user `%s' new password required", user);
+ return retval;
+ case PAM_USER_UNKNOWN:
+ /* the user does not exist */
+ if (ctrl & WINBIND_DEBUG_ARG)
+ _pam_log(LOG_NOTICE, "user `%s' not found",
+ user);
+ if (ctrl & WINBIND_UNKNOWN_OK_ARG) {
+ return PAM_IGNORE;
+ }
+ return retval;
+ case PAM_SUCCESS:
+ if (req_type == WINBINDD_PAM_AUTH) {
+ /* Otherwise, the authentication looked good */
+ _pam_log(LOG_NOTICE, "user '%s' granted acces", user);
+ } else if (req_type == WINBINDD_PAM_CHAUTHTOK) {
+ /* Otherwise, the authentication looked good */
+ _pam_log(LOG_NOTICE, "user '%s' password changed", user);
+ } else {
+ /* Otherwise, the authentication looked good */
+ _pam_log(LOG_NOTICE, "user '%s' OK", user);
+ }
+ return retval;
+ default:
+ /* we don't know anything about this return value */
+ _pam_log(LOG_ERR, "internal module error (retval = %d, user = `%s'",
+ retval, user);
+ return retval;
+ }
+}
+
+/* talk to winbindd */
+static int winbind_auth_request(const char *user, const char *pass, int ctrl)
+{
+ struct winbindd_request request;
+ struct winbindd_response response;
+
+ ZERO_STRUCT(request);
+
+ strncpy(request.data.auth.user, user,
+ sizeof(request.data.auth.user)-1);
+
+ strncpy(request.data.auth.pass, pass,
+ sizeof(request.data.auth.pass)-1);
+
+
+ return pam_winbind_request_log(WINBINDD_PAM_AUTH, &request, &response, ctrl, user);
+}
+
+/* talk to winbindd */
+static int winbind_chauthtok_request(const char *user, const char *oldpass,
+ const char *newpass, int ctrl)
+{
+ struct winbindd_request request;
+ struct winbindd_response response;
+
+ ZERO_STRUCT(request);
+
+ if (request.data.chauthtok.user == NULL) return -2;
+
+ strncpy(request.data.chauthtok.user, user,
+ sizeof(request.data.chauthtok.user) - 1);
+
+ if (oldpass != NULL) {
+ strncpy(request.data.chauthtok.oldpass, oldpass,
+ sizeof(request.data.chauthtok.oldpass) - 1);
+ } else {
+ request.data.chauthtok.oldpass[0] = '\0';
+ }
+
+ if (newpass != NULL) {
+ strncpy(request.data.chauthtok.newpass, newpass,
+ sizeof(request.data.chauthtok.newpass) - 1);
+ } else {
+ request.data.chauthtok.newpass[0] = '\0';
+ }
+
+ return pam_winbind_request_log(WINBINDD_PAM_CHAUTHTOK, &request, &response, ctrl, user);
+}
+
+/*
+ * Checks if a user has an account
+ *
+ * return values:
+ * 1 = User not found
+ * 0 = OK
+ * -1 = System error
+ */
+static int valid_user(const char *user)
+{
+ if (getpwnam(user)) return 0;
+ return 1;
+}
+
+static char *_pam_delete(register char *xx)
+{
+ _pam_overwrite(xx);
+ _pam_drop(xx);
+ return NULL;
+}
+
+/*
+ * obtain a password from the user
+ */
+
+static int _winbind_read_password(pam_handle_t * pamh
+ ,unsigned int ctrl
+ ,const char *comment
+ ,const char *prompt1
+ ,const char *prompt2
+ ,const char **pass)
+{
+ int authtok_flag;
+ int retval;
+ const char *item;
+ char *token;
+
+ /*
+ * make sure nothing inappropriate gets returned
+ */
+
+ *pass = token = NULL;
+
+ /*
+ * which authentication token are we getting?
+ */
+
+ authtok_flag = on(WINBIND__OLD_PASSWORD, ctrl) ? PAM_OLDAUTHTOK : PAM_AUTHTOK;
+
+ /*
+ * should we obtain the password from a PAM item ?
+ */
+
+ if (on(WINBIND_TRY_FIRST_PASS_ARG, ctrl) || on(WINBIND_USE_FIRST_PASS_ARG, ctrl)) {
+ retval = pam_get_item(pamh, authtok_flag, (const void **) &item);
+ if (retval != PAM_SUCCESS) {
+ /* very strange. */
+ _pam_log(LOG_ALERT,
+ "pam_get_item returned error to unix-read-password"
+ );
+ return retval;
+ } else if (item != NULL) { /* we have a password! */
+ *pass = item;
+ item = NULL;
+ return PAM_SUCCESS;
+ } else if (on(WINBIND_USE_FIRST_PASS_ARG, ctrl)) {
+ return PAM_AUTHTOK_RECOVER_ERR; /* didn't work */
+ } else if (on(WINBIND_USE_AUTHTOK_ARG, ctrl)
+ && off(WINBIND__OLD_PASSWORD, ctrl)) {
+ return PAM_AUTHTOK_RECOVER_ERR;
+ }
+ }
+ /*
+ * getting here implies we will have to get the password from the
+ * user directly.
+ */
+
+ {
+ struct pam_message msg[3], *pmsg[3];
+ struct pam_response *resp;
+ int i, replies;
+
+ /* prepare to converse */
+
+ if (comment != NULL) {
+ pmsg[0] = &msg[0];
+ msg[0].msg_style = PAM_TEXT_INFO;
+ msg[0].msg = comment;
+ i = 1;
+ } else {
+ i = 0;
+ }
+
+ pmsg[i] = &msg[i];
+ msg[i].msg_style = PAM_PROMPT_ECHO_OFF;
+ msg[i++].msg = prompt1;
+ replies = 1;
+
+ if (prompt2 != NULL) {
+ pmsg[i] = &msg[i];
+ msg[i].msg_style = PAM_PROMPT_ECHO_OFF;
+ msg[i++].msg = prompt2;
+ ++replies;
+ }
+ /* so call the conversation expecting i responses */
+ resp = NULL;
+ retval = converse(pamh, i, pmsg, &resp);
+
+ if (resp != NULL) {
+
+ /* interpret the response */
+
+ if (retval == PAM_SUCCESS) { /* a good conversation */
+
+ token = x_strdup(resp[i - replies].resp);
+ if (token != NULL) {
+ if (replies == 2) {
+
+ /* verify that password entered correctly */
+ if (!resp[i - 1].resp
+ || strcmp(token, resp[i - 1].resp)) {
+ _pam_delete(token); /* mistyped */
+ retval = PAM_AUTHTOK_RECOVER_ERR;
+ _make_remark(pamh ,PAM_ERROR_MSG, MISTYPED_PASS);
+ }
+ }
+ } else {
+ _pam_log(LOG_NOTICE
+ ,"could not recover authentication token");
+ }
+
+ }
+ /*
+ * tidy up the conversation (resp_retcode) is ignored
+ * -- what is it for anyway? AGM
+ */
+
+ _pam_drop_reply(resp, i);
+
+ } else {
+ retval = (retval == PAM_SUCCESS)
+ ? PAM_AUTHTOK_RECOVER_ERR : retval;
+ }
+ }
+
+ if (retval != PAM_SUCCESS) {
+ if (on(WINBIND_DEBUG_ARG, ctrl))
+ _pam_log(LOG_DEBUG,
+ "unable to obtain a password");
+ return retval;
+ }
+ /* 'token' is the entered password */
+
+ /* we store this password as an item */
+
+ retval = pam_set_item(pamh, authtok_flag, token);
+ _pam_delete(token); /* clean it up */
+ if (retval != PAM_SUCCESS
+ || (retval = pam_get_item(pamh, authtok_flag
+ ,(const void **) &item))
+ != PAM_SUCCESS) {
+
+ _pam_log(LOG_CRIT, "error manipulating password");
+ return retval;
+
+ }
+
+ *pass = item;
+ item = NULL; /* break link to password */
+
+ return PAM_SUCCESS;
+}
+
+PAM_EXTERN
+int pam_sm_authenticate(pam_handle_t *pamh, int flags,
+ int argc, const char **argv)
+{
+ const char *username;
+ const char *password;
+ int retval = PAM_AUTH_ERR;
+
+ /* parse arguments */
+ int ctrl = _pam_parse(argc, argv);
+
+ /* Get the username */
+ retval = pam_get_user(pamh, &username, NULL);
+ if ((retval != PAM_SUCCESS) || (!username)) {
+ if (ctrl & WINBIND_DEBUG_ARG)
+ _pam_log(LOG_DEBUG,"can not get the username");
+ return PAM_SERVICE_ERR;
+ }
+
+ retval = _winbind_read_password(pamh, ctrl, NULL,
+ "Password: ", NULL,
+ &password);
+
+ if (retval != PAM_SUCCESS) {
+ _pam_log(LOG_ERR, "Could not retrieve user's password");
+ return PAM_AUTHTOK_ERR;
+ }
+
+ if (ctrl & WINBIND_DEBUG_ARG) {
+
+ /* Let's not give too much away in the log file */
+
+#ifdef DEBUG_PASSWORD
+ _pam_log(LOG_INFO, "Verify user `%s' with password `%s'",
+ username, password);
+#else
+ _pam_log(LOG_INFO, "Verify user `%s'", username);
+#endif
+ }
+
+ /* Now use the username to look up password */
+ return winbind_auth_request(username, password, ctrl);
+}
+
+PAM_EXTERN
+int pam_sm_setcred(pam_handle_t *pamh, int flags,
+ int argc, const char **argv)
+{
+ return PAM_SUCCESS;
+}
+
+/*
+ * Account management. We want to verify that the account exists
+ * before returning PAM_SUCCESS
+ */
+PAM_EXTERN
+int pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
+ int argc, const char **argv)
+{
+ const char *username;
+ int retval = PAM_USER_UNKNOWN;
+
+ /* parse arguments */
+ int ctrl = _pam_parse(argc, argv);
+
+ /* Get the username */
+ retval = pam_get_user(pamh, &username, NULL);
+ if ((retval != PAM_SUCCESS) || (!username)) {
+ if (ctrl & WINBIND_DEBUG_ARG)
+ _pam_log(LOG_DEBUG,"can not get the username");
+ return PAM_SERVICE_ERR;
+ }
+
+ /* Verify the username */
+ retval = valid_user(username);
+ switch (retval) {
+ case -1:
+ /* some sort of system error. The log was already printed */
+ return PAM_SERVICE_ERR;
+ case 1:
+ /* the user does not exist */
+ if (ctrl & WINBIND_DEBUG_ARG)
+ _pam_log(LOG_NOTICE, "user `%s' not found",
+ username);
+ if (ctrl & WINBIND_UNKNOWN_OK_ARG)
+ return PAM_IGNORE;
+ return PAM_USER_UNKNOWN;
+ case 0:
+ /* Otherwise, the authentication looked good */
+ _pam_log(LOG_NOTICE, "user '%s' granted acces", username);
+ return PAM_SUCCESS;
+ default:
+ /* we don't know anything about this return value */
+ _pam_log(LOG_ERR, "internal module error (retval = %d, user = `%s'",
+ retval, username);
+ return PAM_SERVICE_ERR;
+ }
+
+ /* should not be reached */
+ return PAM_IGNORE;
+}
+PAM_EXTERN
+int pam_sm_open_session(pam_handle_t *pamh, int flags,
+ int argc, const char **argv)
+{
+ /* parse arguments */
+ int ctrl = _pam_parse(argc, argv);
+ if (ctrl & WINBIND_DEBUG_ARG)
+ _pam_log(LOG_DEBUG,"libpam_winbind:pam_sm_open_session handler");
+ return PAM_SUCCESS;
+}
+PAM_EXTERN
+int pam_sm_close_session(pam_handle_t *pamh, int flags,
+ int argc, const char **argv)
+{
+ /* parse arguments */
+ int ctrl = _pam_parse(argc, argv);
+ if (ctrl & WINBIND_DEBUG_ARG)
+ _pam_log(LOG_DEBUG,"libpam_winbind:pam_sm_close_session handler");
+ return PAM_SUCCESS;
+}
+
+
+
+PAM_EXTERN int pam_sm_chauthtok(pam_handle_t * pamh, int flags,
+ int argc, const char **argv)
+{
+ unsigned int lctrl;
+ int retval;
+ unsigned int ctrl = _pam_parse(argc, argv);
+
+ /* <DO NOT free() THESE> */
+ const char *user;
+ char *pass_old, *pass_new;
+ /* </DO NOT free() THESE> */
+
+ char *Announce;
+
+ int retry = 0;
+
+ /*
+ * First get the name of a user
+ */
+ retval = pam_get_user(pamh, &user, "Username: ");
+ if (retval == PAM_SUCCESS) {
+ if (user == NULL) {
+ _pam_log(LOG_ERR, "username was NULL!");
+ return PAM_USER_UNKNOWN;
+ }
+ if (retval == PAM_SUCCESS && on(WINBIND_DEBUG_ARG, ctrl))
+ _pam_log(LOG_DEBUG, "username [%s] obtained",
+ user);
+ } else {
+ if (on(WINBIND_DEBUG_ARG, ctrl))
+ _pam_log(LOG_DEBUG,
+ "password - could not identify user");
+ return retval;
+ }
+
+ /*
+ * obtain and verify the current password (OLDAUTHTOK) for
+ * the user.
+ */
+
+ if (flags & PAM_PRELIM_CHECK) {
+
+ /* instruct user what is happening */
+#define greeting "Changing password for "
+ Announce = (char *) malloc(sizeof(greeting) + strlen(user));
+ if (Announce == NULL) {
+ _pam_log(LOG_CRIT,
+ "password - out of memory");
+ return PAM_BUF_ERR;
+ }
+ (void) strcpy(Announce, greeting);
+ (void) strcpy(Announce + sizeof(greeting) - 1, user);
+#undef greeting
+
+ lctrl = ctrl | WINBIND__OLD_PASSWORD;
+ retval = _winbind_read_password(pamh, lctrl
+ ,Announce
+ ,"(current) NT password: "
+ ,NULL
+ ,(const char **) &pass_old);
+ free(Announce);
+
+ if (retval != PAM_SUCCESS) {
+ _pam_log(LOG_NOTICE
+ ,"password - (old) token not obtained");
+ return retval;
+ }
+ /* verify that this is the password for this user */
+
+ retval = winbind_auth_request(user, pass_old, ctrl);
+
+ if (retval != PAM_ACCT_EXPIRED
+ && retval != PAM_AUTHTOK_EXPIRED
+ && retval != PAM_NEW_AUTHTOK_REQD
+ && retval != PAM_SUCCESS) {
+ pass_old = NULL;
+ return retval;
+ }
+
+ retval = pam_set_item(pamh, PAM_OLDAUTHTOK, (const void *) pass_old);
+ pass_old = NULL;
+ if (retval != PAM_SUCCESS) {
+ _pam_log(LOG_CRIT,
+ "failed to set PAM_OLDAUTHTOK");
+ }
+ } else if (flags & PAM_UPDATE_AUTHTOK) {
+
+ /*
+ * obtain the proposed password
+ */
+
+ /*
+ * get the old token back.
+ */
+
+ retval = pam_get_item(pamh, PAM_OLDAUTHTOK
+ ,(const void **) &pass_old);
+
+ if (retval != PAM_SUCCESS) {
+ _pam_log(LOG_NOTICE, "user not authenticated");
+ return retval;
+ }
+
+ lctrl = ctrl;
+
+ if (on(WINBIND_USE_AUTHTOK_ARG, lctrl)) {
+ ctrl = WINBIND_USE_FIRST_PASS_ARG | lctrl;
+ }
+ retry = 0;
+ retval = PAM_AUTHTOK_ERR;
+ while ((retval != PAM_SUCCESS) && (retry++ < MAX_PASSWD_TRIES)) {
+ /*
+ * use_authtok is to force the use of a previously entered
+ * password -- needed for pluggable password strength checking
+ */
+
+ retval = _winbind_read_password(pamh, lctrl
+ ,NULL
+ ,"Enter new NT password: "
+ ,"Retype new NT password: "
+ ,(const char **) &pass_new);
+
+ if (retval != PAM_SUCCESS) {
+ if (on(WINBIND_DEBUG_ARG, ctrl)) {
+ _pam_log(LOG_ALERT
+ ,"password - new password not obtained");
+ }
+ pass_old = NULL;/* tidy up */
+ return retval;
+ }
+
+ /*
+ * At this point we know who the user is and what they
+ * propose as their new password. Verify that the new
+ * password is acceptable.
+ */
+
+ if (pass_new[0] == '\0') {/* "\0" password = NULL */
+ pass_new = NULL;
+ }
+ }
+
+ /*
+ * By reaching here we have approved the passwords and must now
+ * rebuild the password database file.
+ */
+
+ retval = winbind_chauthtok_request(user, pass_old, pass_new, ctrl);
+ _pam_overwrite(pass_new);
+ _pam_overwrite(pass_old);
+ pass_old = pass_new = NULL;
+ } else {
+ retval = PAM_SERVICE_ERR;
+ }
+
+ return retval;
+}
+
+#ifdef PAM_STATIC
+
+/* static module data */
+
+struct pam_module _pam_winbind_modstruct = {
+ MODULE_NAME,
+ pam_sm_authenticate,
+ pam_sm_setcred,
+ pam_sm_acct_mgmt,
+ pam_sm_open_session,
+ pam_sm_close_session,
+ pam_sm_chauthtok
+};
+
+#endif
+
+/*
+ * Copyright (c) Andrew Tridgell <tridge@samba.org> 2000
+ * Copyright (c) Tim Potter <tpot@samba.org> 2000
+ * Copyright (c) Andrew Bartlettt <abartlet@samba.org> 2002
+ * Copyright (c) Jan Rêkorajski 1999.
+ * Copyright (c) Andrew G. Morgan 1996-8.
+ * Copyright (c) Alex O. Yuriev, 1996.
+ * Copyright (c) Cristian Gafton 1996.
+ * Copyright (C) Elliot Lee <sopwith@redhat.com> 1996, Red Hat Software.
+ *
+ * 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, and the entire permission notice in its entirety,
+ * including the disclaimer of warranties.
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior
+ * written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions. (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED `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.
+ */