sudo/auth/fwtk.c

/*
 * Copyright (c) 1999-2003 Todd C. Miller <Todd.Miller@courtesan.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Sponsored in part by the Defense Advanced Research Projects
 * Agency (DARPA) and Air Force Research Laboratory, Air Force
 * Materiel Command, USAF, under agreement number F39502-99-1-0512.
 */

#include <config.h>

#include <sys/types.h>
#include <sys/param.h>
#include <stdio.h>
#ifdef STDC_HEADERS
# include <stdlib.h>
# include <stddef.h>
#else
# ifdef HAVE_STDLIB_H
#  include <stdlib.h>
# endif
#endif /* STDC_HEADERS */
#ifdef HAVE_STRING_H
# include <string.h>
#else
# ifdef HAVE_STRINGS_H
#  include <strings.h>
# endif
#endif /* HAVE_STRING_H */
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif /* HAVE_UNISTD_H */
#include <pwd.h>

#include <auth.h>
#include <firewall.h>

#include "sudo.h"
#include "sudo_auth.h"

#ifndef lint
__unused static const char rcsid[] = "$Sudo$";
#endif /* lint */

int
fwtk_init(pw, promptp, auth)
    struct passwd *pw;
    char **promptp;
    sudo_auth *auth;
{
    static Cfg *confp;			/* Configuration entry struct */
    char resp[128];			/* Response from the server */

    if ((confp = cfg_read("sudo")) == (Cfg *)-1) {
	warningx("cannot read fwtk config");
	return(AUTH_FATAL);
    }

    if (auth_open(confp)) {
	warningx("cannot connect to authentication server");
	return(AUTH_FATAL);
    }

    /* Get welcome message from auth server */
    if (auth_recv(resp, sizeof(resp))) {
	warningx("lost connection to authentication server");
	return(AUTH_FATAL);
    }
    if (strncmp(resp, "Authsrv ready", 13) != 0) {
	warningx("authentication server error:\n%s", resp);
	return(AUTH_FATAL);
    }

    return(AUTH_SUCCESS);
}

int
fwtk_verify(pw, prompt, auth)
    struct passwd *pw;
    char *prompt;
    sudo_auth *auth;
{
    char *pass;				/* Password from the user */
    char buf[SUDO_PASS_MAX + 12];	/* General prupose buffer */
    char resp[128];			/* Response from the server */
    int error;
    extern int nil_pw;

    /* Send username to authentication server. */
    (void) snprintf(buf, sizeof(buf), "authorize %s 'sudo'", pw->pw_name);
restart:
    if (auth_send(buf) || auth_recv(resp, sizeof(resp))) {
	warningx("lost connection to authentication server");
	return(AUTH_FATAL);
    }

    /* Get the password/response from the user. */
    if (strncmp(resp, "challenge ", 10) == 0) {
	(void) snprintf(buf, sizeof(buf), "%s\nResponse: ", &resp[10]);
	pass = tgetpass(buf, def_passwd_timeout * 60, tgetpass_flags);
	if (pass && *pass == '\0') {
	    pass = tgetpass("Response [echo on]: ",
		def_passwd_timeout * 60, tgetpass_flags | TGP_ECHO);
	}
    } else if (strncmp(resp, "chalnecho ", 10) == 0) {
	pass = tgetpass(&resp[10], def_passwd_timeout * 60, tgetpass_flags);
    } else if (strncmp(resp, "password", 8) == 0) {
	pass = tgetpass(prompt, def_passwd_timeout * 60,
	    tgetpass_flags);
    } else if (strncmp(resp, "display ", 8) == 0) {
	fprintf(stderr, "%s\n", &resp[8]);
	strlcpy(buf, "response dummy", sizeof(buf));
	goto restart;
    } else {
	warningx("%s", resp);
	return(AUTH_FATAL);
    }
    if (!pass) {			/* ^C or error */
	nil_pw = 1;
	return(AUTH_FAILURE);
    } else if (*pass == '\0')		/* empty password */
	nil_pw = 1;

    /* Send the user's response to the server */
    (void) snprintf(buf, sizeof(buf), "response '%s'", pass);
    if (auth_send(buf) || auth_recv(resp, sizeof(resp))) {
	warningx("lost connection to authentication server");
	error = AUTH_FATAL;
	goto done;
    }

    if (strncmp(resp, "ok", 2) == 0) {
	error = AUTH_SUCCESS;
	goto done;
    }

    /* Main loop prints "Permission Denied" or insult. */
    if (strcmp(resp, "Permission Denied.") != 0)
	warningx("%s", resp);
    error = AUTH_FAILURE;
done:
    zero_bytes(pass, strlen(pass));
    zero_bytes(buf, strlen(buf));
    return(error);
}

int
fwtk_cleanup(pw, auth)
    struct passwd *pw;
    sudo_auth *auth;
{

    auth_close();
    return(AUTH_SUCCESS);
}