783 lines
20 KiB
C
783 lines
20 KiB
C
/*
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* Copyright (c) 2000 Damien Miller. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "includes.h"
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#ifdef USE_PAM
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#include <security/pam_appl.h>
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#include "ssh.h"
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#include "xmalloc.h"
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#include "log.h"
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#include "servconf.h"
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#include "readpass.h"
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#include "canohost.h"
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RCSID("$FreeBSD$");
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#define NEW_AUTHTOK_MSG \
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"Warning: Your password has expired, please change it now"
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#define SSHD_PAM_SERVICE "sshd"
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#define PAM_STRERROR(a, b) pam_strerror((a), (b))
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/* Callbacks */
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static int pamconv(int num_msg, const struct pam_message **msg,
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struct pam_response **resp, void *appdata_ptr);
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void pam_cleanup_proc(void *context);
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void pam_msg_cat(const char *msg);
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/* module-local variables */
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static struct pam_conv conv = {
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pamconv,
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NULL
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};
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static pam_handle_t *pamh = NULL;
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static const char *pampasswd = NULL;
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static char *pam_msg = NULL;
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extern ServerOptions options;
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/* states for pamconv() */
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typedef enum { INITIAL_LOGIN, OTHER } pamstates;
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static pamstates pamstate = INITIAL_LOGIN;
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/* remember whether pam_acct_mgmt() returned PAM_NEWAUTHTOK_REQD */
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static int password_change_required = 0;
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/*
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* PAM conversation function.
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* There are two states this can run in.
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*
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* INITIAL_LOGIN mode simply feeds the password from the client into
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* PAM in response to PAM_PROMPT_ECHO_OFF, and collects output
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* messages with pam_msg_cat(). This is used during initial
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* authentication to bypass the normal PAM password prompt.
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*
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* OTHER mode handles PAM_PROMPT_ECHO_OFF with read_passphrase(prompt, 1)
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* and outputs messages to stderr. This mode is used if pam_chauthtok()
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* is called to update expired passwords.
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*/
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static int pamconv(int num_msg, const struct pam_message **msg,
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struct pam_response **resp, void *appdata_ptr)
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{
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struct pam_response *reply;
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int count;
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char buf[1024];
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/* PAM will free this later */
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reply = malloc(num_msg * sizeof(*reply));
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if (reply == NULL)
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return PAM_CONV_ERR;
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for (count = 0; count < num_msg; count++) {
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switch ((*msg)[count].msg_style) {
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case PAM_PROMPT_ECHO_ON:
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if (pamstate == INITIAL_LOGIN) {
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free(reply);
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return PAM_CONV_ERR;
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} else {
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fputs((*msg)[count].msg, stderr);
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fgets(buf, sizeof(buf), stdin);
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reply[count].resp = xstrdup(buf);
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reply[count].resp_retcode = PAM_SUCCESS;
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break;
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}
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case PAM_PROMPT_ECHO_OFF:
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if (pamstate == INITIAL_LOGIN) {
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if (pampasswd == NULL) {
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free(reply);
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return PAM_CONV_ERR;
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}
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reply[count].resp = xstrdup(pampasswd);
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} else {
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reply[count].resp =
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xstrdup(read_passphrase((*msg)[count].msg, 1));
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}
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reply[count].resp_retcode = PAM_SUCCESS;
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break;
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case PAM_ERROR_MSG:
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case PAM_TEXT_INFO:
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if ((*msg)[count].msg != NULL) {
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if (pamstate == INITIAL_LOGIN)
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pam_msg_cat((*msg)[count].msg);
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else {
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fputs((*msg)[count].msg, stderr);
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fputs("\n", stderr);
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}
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}
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reply[count].resp = xstrdup("");
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reply[count].resp_retcode = PAM_SUCCESS;
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break;
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default:
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free(reply);
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return PAM_CONV_ERR;
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}
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}
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*resp = reply;
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return PAM_SUCCESS;
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}
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/* Called at exit to cleanly shutdown PAM */
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void pam_cleanup_proc(void *context)
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{
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int pam_retval;
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if (pamh != NULL)
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{
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pam_retval = pam_close_session(pamh, 0);
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if (pam_retval != PAM_SUCCESS) {
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log("Cannot close PAM session[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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pam_retval = pam_setcred(pamh, PAM_DELETE_CRED);
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if (pam_retval != PAM_SUCCESS) {
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debug("Cannot delete credentials[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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pam_retval = pam_end(pamh, pam_retval);
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if (pam_retval != PAM_SUCCESS) {
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log("Cannot release PAM authentication[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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}
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}
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/* Attempt password authentation using PAM */
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int auth_pam_password(Authctxt *authctxt, const char *password)
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{
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struct passwd *pw = authctxt->pw;
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int pam_retval;
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/* deny if no user. */
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if (pw == NULL)
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return 0;
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if (pw->pw_uid == 0 && options.permit_root_login == 2)
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return 0;
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if (*password == '\0' && options.permit_empty_passwd == 0)
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return 0;
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pampasswd = password;
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pamstate = INITIAL_LOGIN;
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pam_retval = pam_authenticate(pamh, 0);
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if (pam_retval == PAM_SUCCESS) {
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debug("PAM Password authentication accepted for user \"%.100s\"",
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pw->pw_name);
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return 1;
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} else {
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debug("PAM Password authentication for \"%.100s\" failed[%d]: %s",
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pw->pw_name, pam_retval, PAM_STRERROR(pamh, pam_retval));
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return 0;
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}
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}
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/* Do account management using PAM */
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int do_pam_account(char *username, char *remote_user)
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{
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int pam_retval;
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debug("PAM setting rhost to \"%.200s\"",
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get_canonical_hostname(options.reverse_mapping_check));
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pam_retval = pam_set_item(pamh, PAM_RHOST,
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get_canonical_hostname(options.reverse_mapping_check));
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM set rhost failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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if (remote_user != NULL) {
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debug("PAM setting ruser to \"%.200s\"", remote_user);
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pam_retval = pam_set_item(pamh, PAM_RUSER, remote_user);
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM set ruser failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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}
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pam_retval = pam_acct_mgmt(pamh, 0);
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switch (pam_retval) {
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case PAM_SUCCESS:
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/* This is what we want */
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break;
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case PAM_NEW_AUTHTOK_REQD:
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pam_msg_cat(NEW_AUTHTOK_MSG);
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/* flag that password change is necessary */
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password_change_required = 1;
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break;
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default:
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log("PAM rejected by account configuration[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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return(0);
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}
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return(1);
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}
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/* Do PAM-specific session initialisation */
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void do_pam_session(char *username, const char *ttyname)
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{
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int pam_retval;
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if (ttyname != NULL) {
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debug("PAM setting tty to \"%.200s\"", ttyname);
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pam_retval = pam_set_item(pamh, PAM_TTY, ttyname);
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM set tty failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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}
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debug("do_pam_session: euid %u, uid %u", geteuid(), getuid());
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pam_retval = pam_open_session(pamh, 0);
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM session setup failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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}
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/* Set PAM credentials */
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void do_pam_setcred(void)
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{
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int pam_retval;
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debug("PAM establishing creds");
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pam_retval = pam_setcred(pamh, PAM_ESTABLISH_CRED);
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM setcred failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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}
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/* accessor function for file scope static variable */
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int pam_password_change_required(void)
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{
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return password_change_required;
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}
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/*
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* Have user change authentication token if pam_acct_mgmt() indicated
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* it was expired. This needs to be called after an interactive
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* session is established and the user's pty is connected to
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* stdin/stout/stderr.
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*/
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void do_pam_chauthtok(void)
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{
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int pam_retval;
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if (password_change_required) {
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pamstate = OTHER;
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/*
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* XXX: should we really loop forever?
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*/
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do {
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pam_retval = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
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if (pam_retval != PAM_SUCCESS) {
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log("PAM pam_chauthtok failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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} while (pam_retval != PAM_SUCCESS);
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}
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}
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/* Cleanly shutdown PAM */
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void finish_pam(void)
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{
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pam_cleanup_proc(NULL);
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fatal_remove_cleanup(&pam_cleanup_proc, NULL);
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}
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/* Start PAM authentication for specified account */
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void start_pam(struct passwd *pw)
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{
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int pam_retval;
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debug("Starting up PAM with username \"%.200s\"", pw->pw_name);
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pam_retval = pam_start(SSHD_PAM_SERVICE, pw->pw_name, &conv, &pamh);
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM initialisation failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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#ifdef PAM_TTY_KLUDGE
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/*
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* Some PAM modules (e.g. pam_time) require a TTY to operate,
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* and will fail in various stupid ways if they don't get one.
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* sshd doesn't set the tty until too late in the auth process and may
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* not even need one (for tty-less connections)
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* Kludge: Set a fake PAM_TTY
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*/
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pam_retval = pam_set_item(pamh, PAM_TTY, "ssh");
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if (pam_retval != PAM_SUCCESS) {
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fatal("PAM set tty failed[%d]: %.200s",
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pam_retval, PAM_STRERROR(pamh, pam_retval));
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}
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#endif /* PAM_TTY_KLUDGE */
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fatal_add_cleanup(&pam_cleanup_proc, NULL);
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}
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/* Return list of PAM enviornment strings */
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char **fetch_pam_environment(void)
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{
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#ifdef HAVE_PAM_GETENVLIST
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return(pam_getenvlist(pamh));
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#else /* HAVE_PAM_GETENVLIST */
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return(NULL);
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#endif /* HAVE_PAM_GETENVLIST */
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}
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/* Print any messages that have been generated during authentication */
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/* or account checking to stderr */
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void print_pam_messages(void)
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{
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if (pam_msg != NULL)
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fputs(pam_msg, stderr);
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}
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/* Append a message to the PAM message buffer */
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void pam_msg_cat(const char *msg)
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{
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char *p;
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size_t new_msg_len;
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size_t pam_msg_len;
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new_msg_len = strlen(msg);
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if (pam_msg) {
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pam_msg_len = strlen(pam_msg);
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pam_msg = xrealloc(pam_msg, new_msg_len + pam_msg_len + 2);
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p = pam_msg + pam_msg_len;
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} else {
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pam_msg = p = xmalloc(new_msg_len + 2);
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}
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memcpy(p, msg, new_msg_len);
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p[new_msg_len] = '\n';
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p[new_msg_len + 1] = '\0';
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}
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struct inverted_pam_userdata {
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/*
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* Pipe for telling whether we are doing conversation or sending
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* authentication results.
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*/
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int statefd[2];
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int challengefd[2];
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int responsefd[2];
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/* Whether we have sent off our challenge */
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int state;
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};
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#define STATE_CONV 1
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#define STATE_AUTH_OK 2
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#define STATE_AUTH_FAIL 3
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int
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ssh_conv(int num_msg, const struct pam_message **msg, struct pam_response **resp,
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void *userdata) {
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int i;
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FILE *reader;
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char buf[1024];
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struct pam_response *reply = NULL;
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char state_to_write = STATE_CONV; /* One char to write */
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struct inverted_pam_userdata *ud = userdata;
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char *response = NULL;
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/* The stdio functions are more convenient for the read half */
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reader = fdopen(ud->responsefd[0], "rb");
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if (reader == NULL)
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goto protocol_failure;
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reply = malloc(num_msg * sizeof(struct pam_response));
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if (reply == NULL)
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return PAM_CONV_ERR;
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if (write(ud->statefd[1], &state_to_write, 1) != 1)
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goto protocol_failure;
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/*
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* Re-package our data and send it off to our better half (the actual SSH
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* process)
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*/
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if (write(ud->challengefd[1], buf,
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sprintf(buf, "%d\n", num_msg)) == -1)
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goto protocol_failure;
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for (i = 0; i < num_msg; i++) {
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if (write(ud->challengefd[1], buf,
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sprintf(buf, "%d\n", msg[i]->msg_style)) == -1)
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goto protocol_failure;
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if (write(ud->challengefd[1], buf,
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sprintf(buf, "%d\n", strlen(msg[i]->msg))) == -1)
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goto protocol_failure;
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if (write(ud->challengefd[1], msg[i]->msg,
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strlen(msg[i]->msg)) == -1)
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goto protocol_failure;
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}
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/*
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* Read back responses. These may not be as nice as we want, as the SSH
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* protocol isn't exactly a perfect fit with PAM.
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*/
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for (i = 0; i < num_msg; i++) {
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char buf[1024];
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char *endptr;
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size_t len; /* Length of the response */
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switch (msg[i]->msg_style) {
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case PAM_PROMPT_ECHO_OFF:
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case PAM_PROMPT_ECHO_ON:
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if (fgets(buf, sizeof(buf), reader) == NULL)
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goto protocol_failure;
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len = (size_t)strtoul(buf, &endptr, 10);
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/* The length is supposed to stand on a line by itself */
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if (endptr == NULL || *endptr != '\n')
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goto protocol_failure;
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response = malloc(len+1);
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if (response == NULL)
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goto protocol_failure;
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if (fread(response, len, 1, reader) != 1)
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goto protocol_failure;
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response[len] = '\0';
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reply[i].resp = response;
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response = NULL;
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break;
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default:
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reply[i].resp = NULL;
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break;
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}
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}
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*resp = reply;
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return PAM_SUCCESS;
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protocol_failure:
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free(reply);
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return PAM_CONV_ERR;
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}
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void
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ipam_free_cookie(struct inverted_pam_cookie *cookie) {
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struct inverted_pam_userdata *ud;
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int i;
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if (cookie == NULL)
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return;
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ud = cookie->userdata;
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cookie->userdata = NULL;
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/* Free userdata if allocated */
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if (ud) {
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/* Close any opened file descriptors */
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if (ud->statefd[0] != -1)
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close(ud->statefd[0]);
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if (ud->statefd[1] != -1)
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close(ud->statefd[1]);
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if (ud->challengefd[0] != -1)
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close(ud->challengefd[0]);
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if (ud->challengefd[1] != -1)
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close(ud->challengefd[1]);
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if (ud->responsefd[0] != -1)
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close(ud->responsefd[0]);
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if (ud->responsefd[1] != -1)
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close(ud->responsefd[1]);
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free(ud);
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ud = NULL;
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}
|
|
/* Now free the normal cookie */
|
|
if (cookie->pid != 0 && cookie->pid != -1) {
|
|
int status;
|
|
|
|
/* XXX Use different signal? */
|
|
kill(cookie->pid, SIGKILL);
|
|
waitpid(cookie->pid, &status, 0);
|
|
}
|
|
for (i = 0; i < cookie->num_msg; i++) {
|
|
if (cookie->resp && cookie->resp[i]) {
|
|
free(cookie->resp[i]->resp);
|
|
free(cookie->resp[i]);
|
|
}
|
|
if (cookie->msg && cookie->msg[i]) {
|
|
free((void *)cookie->msg[i]->msg);
|
|
free(cookie->msg[i]);
|
|
}
|
|
}
|
|
free(cookie->msg);
|
|
free(cookie->resp);
|
|
free(cookie);
|
|
}
|
|
|
|
/*
|
|
* Do first half of PAM authentication - this comes to the point where
|
|
* you get a message to send to the user.
|
|
*/
|
|
struct inverted_pam_cookie *
|
|
ipam_start_auth(const char *service, const char *username) {
|
|
struct inverted_pam_cookie *cookie;
|
|
struct inverted_pam_userdata *ud;
|
|
static struct pam_conv conv = {
|
|
ssh_conv,
|
|
NULL
|
|
};
|
|
|
|
cookie = malloc(sizeof(*cookie));
|
|
if (cookie == NULL)
|
|
return NULL;
|
|
cookie->state = 0;
|
|
/* Set up the cookie so ipam_freecookie can be used on it */
|
|
cookie->num_msg = 0;
|
|
cookie->msg = NULL;
|
|
cookie->resp = NULL;
|
|
cookie->pid = -1;
|
|
|
|
ud = calloc(sizeof(*ud), 1);
|
|
if (ud == NULL) {
|
|
free(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->userdata = ud;
|
|
ud->statefd[0] = ud->statefd[1] = -1;
|
|
ud->challengefd[0] = ud->challengefd[1] = -1;
|
|
ud->responsefd[0] = ud->responsefd[1] = -1;
|
|
|
|
if (pipe(ud->statefd) != 0) {
|
|
ud->statefd[0] = ud->statefd[1] = -1;
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
if (pipe(ud->challengefd) != 0) {
|
|
ud->challengefd[0] = ud->challengefd[1] = -1;
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
if (pipe(ud->responsefd) != 0) {
|
|
ud->responsefd[0] = ud->responsefd[1] = -1;
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->pid = fork();
|
|
if (cookie->pid == -1) {
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
} else if (cookie->pid != 0) {
|
|
int num_msgs; /* Number of messages from PAM */
|
|
char *endptr;
|
|
char buf[1024];
|
|
FILE *reader;
|
|
size_t num_msg;
|
|
int i;
|
|
char state; /* Which state did the connection just enter? */
|
|
|
|
/* We are the parent - wait for a call to the communications
|
|
function to turn up, or the challenge to be finished */
|
|
if (read(ud->statefd[0], &state, 1) != 1) {
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->state = state;
|
|
switch (state) {
|
|
case STATE_CONV:
|
|
/* We are running the conversation function */
|
|
/* The stdio functions are more convenient for read */
|
|
reader = fdopen(ud->challengefd[0], "r");
|
|
if (reader == NULL) {
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
if (fgets(buf, 4, reader) == NULL) {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
num_msg = (size_t)strtoul(buf, &endptr, 10);
|
|
/* The length is supposed to stand on a line by itself */
|
|
if (endptr == NULL || *endptr != '\n') {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->msg =
|
|
malloc(sizeof(struct pam_message *) * num_msg);
|
|
cookie->resp =
|
|
malloc(sizeof(struct pam_response *) * num_msg);
|
|
if (cookie->msg == NULL || cookie->resp == NULL) {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
for (i = 0; i < num_msg; i++) {
|
|
cookie->msg[i] =
|
|
malloc(sizeof(struct pam_message));
|
|
cookie->resp[i] =
|
|
malloc(sizeof(struct pam_response));
|
|
if (cookie->msg[i] == NULL ||
|
|
cookie->resp[i] == NULL) {
|
|
for (;;) {
|
|
free(cookie->msg[i]);
|
|
free(cookie->resp[i]);
|
|
if (i == 0)
|
|
break;
|
|
i--;
|
|
}
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->msg[i]->msg = NULL;
|
|
cookie->resp[i]->resp = NULL;
|
|
cookie->resp[i]->resp_retcode = 0;
|
|
}
|
|
/* Set up so the above will be freed on failure */
|
|
cookie->num_msg = num_msg;
|
|
/*
|
|
* We have a an allocated response and message for
|
|
* each of the entries in the PAM structure - transfer
|
|
* the data sent to the conversation function over.
|
|
*/
|
|
for (i = 0; i < num_msg; i++) {
|
|
size_t len;
|
|
|
|
if (fgets(buf, sizeof(buf), reader) == NULL) {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->msg[i]->msg_style =
|
|
(size_t)strtoul(buf, &endptr, 10);
|
|
if (endptr == NULL || *endptr != '\n') {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
if (fgets(buf, sizeof(buf), reader) == NULL) {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
len = (size_t)strtoul(buf, &endptr, 10);
|
|
if (endptr == NULL || *endptr != '\n') {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
cookie->msg[i]->msg = malloc(len + 1);
|
|
if (cookie->msg[i]->msg == NULL) {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
if (fread((char *)cookie->msg[i]->msg, len, 1, reader) !=
|
|
1) {
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
*(char *)&(cookie->msg[i]->msg[len]) = '\0';
|
|
}
|
|
break;
|
|
case STATE_AUTH_OK:
|
|
case STATE_AUTH_FAIL:
|
|
break;
|
|
default:
|
|
/* Internal failure, somehow */
|
|
fclose(reader);
|
|
ipam_free_cookie(cookie);
|
|
return NULL;
|
|
}
|
|
return cookie;
|
|
} else {
|
|
/* We are the child */
|
|
pam_handle_t *pamh=NULL;
|
|
int retval;
|
|
char state;
|
|
|
|
conv.appdata_ptr = ud;
|
|
retval = pam_start(service, username, &conv, &pamh);
|
|
/* Is user really user? */
|
|
if (retval == PAM_SUCCESS)
|
|
retval = pam_authenticate(pamh, 0);
|
|
/* permitted access? */
|
|
if (retval == PAM_SUCCESS)
|
|
retval = pam_acct_mgmt(pamh, 0);
|
|
/* This is where we have been authorized or not. */
|
|
|
|
/* Be conservative - flag as auth failure if we can't close */
|
|
/*
|
|
* XXX This is based on example code from Linux-PAM -
|
|
* but can it really be correct to pam_end if
|
|
* pam_start failed?
|
|
*/
|
|
if (pam_end(pamh, retval) != PAM_SUCCESS)
|
|
retval = PAM_AUTH_ERR;
|
|
|
|
/* Message to parent */
|
|
state = retval == PAM_SUCCESS ? STATE_AUTH_OK : STATE_AUTH_FAIL;
|
|
if (write(ud->statefd[1], &state, 1) != 1) {
|
|
_exit(1);
|
|
}
|
|
/* FDs will be closed, so further communication will stop */
|
|
_exit(0);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Do second half of PAM authentication - cookie should now be filled
|
|
* in with the response to the challenge.
|
|
*/
|
|
|
|
int
|
|
ipam_complete_auth(struct inverted_pam_cookie *cookie) {
|
|
int i;
|
|
char buf[1024];
|
|
struct inverted_pam_userdata *ud = cookie->userdata;
|
|
char state;
|
|
|
|
/* Send over our responses */
|
|
for (i = 0; i < cookie->num_msg; i++) {
|
|
if (cookie->msg[i]->msg_style != PAM_PROMPT_ECHO_ON &&
|
|
cookie->msg[i]->msg_style != PAM_PROMPT_ECHO_OFF)
|
|
continue;
|
|
if (write(ud->responsefd[1], buf,
|
|
sprintf(buf, "%d\n", strlen(cookie->resp[i]->resp))) == -1) {
|
|
ipam_free_cookie(cookie);
|
|
return 0;
|
|
}
|
|
if (write(ud->responsefd[1], cookie->resp[i]->resp,
|
|
strlen(cookie->resp[i]->resp)) == -1) {
|
|
ipam_free_cookie(cookie);
|
|
return 0;
|
|
}
|
|
}
|
|
/* Find out what state we are changing to */
|
|
if (read(ud->statefd[0], &state, 1) != 1) {
|
|
ipam_free_cookie(cookie);
|
|
return 0;
|
|
}
|
|
|
|
return state == STATE_AUTH_OK ? 1 : 0;
|
|
}
|
|
|
|
#endif /* USE_PAM */
|