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/* $OpenBSD: raddauth.c,v 1.29 2016/09/03 11:04:23 gsoares Exp $ */ |
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/*- |
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* Copyright (c) 1996, 1997 Berkeley Software Design, Inc. 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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* 3. All advertising materials mentioning features or use of this software |
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* must display the following acknowledgement: |
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* This product includes software developed by Berkeley Software Design, |
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* Inc. |
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* 4. The name of Berkeley Software Design, Inc. may not be used to endorse |
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* or promote products derived from this software without specific prior |
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* written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN, INC. ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN, INC. BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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* |
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* BSDI $From: raddauth.c,v 1.6 1998/04/14 00:39:04 prb Exp $ |
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*/ |
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/* |
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* Copyright(c) 1996 by tfm associates. |
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* All rights reserved. |
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* |
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* tfm associates |
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* P.O. Box 2086 |
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* Eugene OR 97402-0031 |
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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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* 3. The name of tfm associates may not be used to endorse or promote |
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* products derived from this software without specific prior written |
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* permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY TFM ASSOC``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 TFM ASSOCIATES 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 THEORY |
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* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, |
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* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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*/ |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <netinet/in.h> |
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#include <arpa/inet.h> |
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#include <ctype.h> |
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#include <err.h> |
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#include <errno.h> |
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#include <stdint.h> |
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#include <limits.h> |
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#include <login_cap.h> |
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#include <netdb.h> |
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#include <signal.h> |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <syslog.h> |
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#include <time.h> |
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#include <unistd.h> |
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#include <md5.h> |
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#include <readpassphrase.h> |
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#include "login_radius.h" |
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#define MAXPWNETNAM 64 /* longest username */ |
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#define MAXSECRETLEN 128 /* maximum length of secret */ |
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#define AUTH_VECTOR_LEN 16 |
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#define AUTH_HDR_LEN 20 |
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#define AUTH_PASS_LEN (256 - 16) |
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#define PW_AUTHENTICATION_REQUEST 1 |
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#define PW_AUTHENTICATION_ACK 2 |
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#define PW_AUTHENTICATION_REJECT 3 |
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#define PW_ACCESS_CHALLENGE 11 |
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#define PW_USER_NAME 1 |
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#define PW_PASSWORD 2 |
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#define PW_CLIENT_ID 4 |
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#define PW_CLIENT_PORT_ID 5 |
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#define PW_PORT_MESSAGE 18 |
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#define PW_STATE 24 |
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#ifndef RADIUS_DIR |
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#define RADIUS_DIR "/etc/raddb" |
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#endif |
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#define RADIUS_SERVERS "servers" |
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char *radius_dir = RADIUS_DIR; |
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char auth_secret[MAXSECRETLEN+1]; |
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volatile sig_atomic_t timedout; |
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int alt_retries; |
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int retries; |
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int sockfd; |
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int timeout; |
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in_addr_t alt_server; |
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in_addr_t auth_server; |
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in_port_t radius_port; |
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typedef struct { |
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u_char code; |
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u_char id; |
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u_short length; |
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u_char vector[AUTH_VECTOR_LEN]; |
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u_char data[4096 - AUTH_HDR_LEN]; |
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} auth_hdr_t; |
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void servtimeout(int); |
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in_addr_t get_ipaddr(char *); |
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in_addr_t gethost(void); |
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int rad_recv(char *, char *, u_char *); |
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void parse_challenge(auth_hdr_t *, char *, char *); |
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void rad_request(u_char, char *, char *, int, char *, char *); |
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void getsecret(void); |
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/* |
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* challenge -- NULL for interactive service |
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* password -- NULL for interactive service and when requesting a challenge |
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*/ |
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int |
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raddauth(char *username, char *class, char *style, char *challenge, |
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char *password, char **emsg) |
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{ |
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static char _pwstate[1024]; |
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u_char req_id; |
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char *userstyle, *passwd, *pwstate, *rad_service; |
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char pbuf[AUTH_PASS_LEN+1]; |
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int auth_port; |
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char vector[AUTH_VECTOR_LEN+1], *p, *v; |
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int i; |
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login_cap_t *lc; |
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u_int32_t r; |
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struct servent *svp; |
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struct sockaddr_in sin; |
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struct sigaction sa; |
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const char *errstr; |
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memset(_pwstate, 0, sizeof(_pwstate)); |
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pwstate = password ? challenge : _pwstate; |
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if ((lc = login_getclass(class)) == NULL) { |
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snprintf(_pwstate, sizeof(_pwstate), |
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"%s: no such class", class); |
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*emsg = _pwstate; |
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return (1); |
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} |
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rad_service = login_getcapstr(lc, "radius-port", "radius", "radius"); |
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timeout = login_getcapnum(lc, "radius-timeout", 2, 2); |
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retries = login_getcapnum(lc, "radius-retries", 6, 6); |
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177 |
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if (timeout < 1) |
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timeout = 1; |
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if (retries < 2) |
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retries = 2; |
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if (challenge == NULL) { |
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passwd = NULL; |
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v = login_getcapstr(lc, "radius-challenge-styles", |
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NULL, NULL); |
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i = strlen(style); |
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while (v && (p = strstr(v, style)) != NULL) { |
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if ((p == v || p[-1] == ',') && |
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(p[i] == ',' || p[i] == '\0')) { |
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passwd = ""; |
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break; |
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} |
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v = p+1; |
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} |
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if (passwd == NULL) |
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passwd = readpassphrase("Password:", pbuf, sizeof(pbuf), |
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RPP_ECHO_OFF); |
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} else |
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passwd = password; |
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if (passwd == NULL) |
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passwd = ""; |
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if ((v = login_getcapstr(lc, "radius-server", NULL, NULL)) == NULL){ |
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*emsg = "radius-server not configured"; |
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return (1); |
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} |
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auth_server = get_ipaddr(v); |
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if ((v = login_getcapstr(lc, "radius-server-alt", NULL, NULL)) == NULL) |
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alt_server = 0; |
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else { |
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alt_server = get_ipaddr(v); |
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alt_retries = retries/2; |
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retries >>= 1; |
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} |
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/* get port number */ |
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radius_port = strtonum(rad_service, 1, UINT16_MAX, &errstr); |
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if (errstr) { |
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svp = getservbyname(rad_service, "udp"); |
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if (svp == NULL) { |
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snprintf(_pwstate, sizeof(_pwstate), |
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"No such service: %s/udp", rad_service); |
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*emsg = _pwstate; |
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return (1); |
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} |
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radius_port = svp->s_port; |
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} else |
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radius_port = htons(radius_port); |
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/* get the secret from the servers file */ |
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getsecret(); |
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/* set up socket */ |
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if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) { |
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snprintf(_pwstate, sizeof(_pwstate), "%s", strerror(errno)); |
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*emsg = _pwstate; |
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return (1); |
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} |
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242 |
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/* set up client structure */ |
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memset(&sin, 0, sizeof(sin)); |
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sin.sin_family = AF_INET; |
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sin.sin_addr.s_addr = INADDR_ANY; |
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sin.sin_port = radius_port; |
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req_id = (u_char) arc4random(); |
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auth_port = ttyslot(); |
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if (auth_port == 0) |
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auth_port = (int)getppid(); |
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if (strcmp(style, "radius") != 0) { |
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if (asprintf(&userstyle, "%s:%s", username, style) == -1) |
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err(1, NULL); |
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} else |
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userstyle = username; |
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258 |
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/* generate random vector */ |
259 |
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for (i = 0; i < AUTH_VECTOR_LEN;) { |
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r = arc4random(); |
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memcpy(&vector[i], &r, sizeof(r)); |
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i += sizeof(r); |
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} |
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vector[AUTH_VECTOR_LEN] = '\0'; |
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266 |
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sigemptyset(&sa.sa_mask); |
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sa.sa_handler = servtimeout; |
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sa.sa_flags = 0; /* don't restart system calls */ |
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(void)sigaction(SIGALRM, &sa, NULL); |
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retry: |
271 |
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if (timedout) { |
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timedout = 0; |
273 |
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if (--retries <= 0) { |
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/* |
275 |
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* If we ran out of tries but there is an alternate |
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* server, switch to it and try again. |
277 |
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*/ |
278 |
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if (alt_retries) { |
279 |
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auth_server = alt_server; |
280 |
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retries = alt_retries; |
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alt_retries = 0; |
282 |
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getsecret(); |
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} else |
284 |
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warnx("no response from authentication server"); |
285 |
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} |
286 |
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} |
287 |
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288 |
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if (retries > 0) { |
289 |
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rad_request(req_id, userstyle, passwd, auth_port, vector, |
290 |
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pwstate); |
291 |
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292 |
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switch (i = rad_recv(_pwstate, challenge, vector)) { |
293 |
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case PW_AUTHENTICATION_ACK: |
294 |
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/* |
295 |
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* Make sure we don't think a challenge was issued. |
296 |
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*/ |
297 |
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if (challenge) |
298 |
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*challenge = '\0'; |
299 |
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return (0); |
300 |
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|
301 |
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case PW_AUTHENTICATION_REJECT: |
302 |
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return (1); |
303 |
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|
304 |
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case PW_ACCESS_CHALLENGE: |
305 |
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/* |
306 |
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* If this is a response then reject them if |
307 |
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* we got a challenge. |
308 |
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*/ |
309 |
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if (password) |
310 |
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return (1); |
311 |
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/* |
312 |
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* If we wanted a challenge, just return |
313 |
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*/ |
314 |
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if (challenge) { |
315 |
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if (strcmp(challenge, _pwstate) != 0) |
316 |
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syslog(LOG_WARNING, |
317 |
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"challenge for %s does not match state", |
318 |
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userstyle); |
319 |
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return (0); |
320 |
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} |
321 |
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req_id++; |
322 |
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if ((passwd = readpassphrase("", pbuf, sizeof(pbuf), |
323 |
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RPP_ECHO_OFF)) == NULL) |
324 |
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passwd = ""; |
325 |
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break; |
326 |
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327 |
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default: |
328 |
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if (timedout) |
329 |
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goto retry; |
330 |
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snprintf(_pwstate, sizeof(_pwstate), |
331 |
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"invalid response type %d\n", i); |
332 |
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*emsg = _pwstate; |
333 |
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return (1); |
334 |
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} |
335 |
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} |
336 |
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return (1); |
337 |
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} |
338 |
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|
339 |
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/* |
340 |
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* Build a radius authentication digest and submit it to the radius server |
341 |
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*/ |
342 |
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void |
343 |
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rad_request(u_char id, char *name, char *password, int port, char *vector, |
344 |
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char *state) |
345 |
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{ |
346 |
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auth_hdr_t auth; |
347 |
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int i, len, secretlen, total_length, p; |
348 |
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struct sockaddr_in sin; |
349 |
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u_char md5buf[MAXSECRETLEN+AUTH_VECTOR_LEN], digest[AUTH_VECTOR_LEN], |
350 |
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pass_buf[AUTH_PASS_LEN], *pw, *ptr; |
351 |
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u_int length; |
352 |
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in_addr_t ipaddr; |
353 |
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MD5_CTX context; |
354 |
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|
355 |
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memset(&auth, 0, sizeof(auth)); |
356 |
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auth.code = PW_AUTHENTICATION_REQUEST; |
357 |
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auth.id = id; |
358 |
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memcpy(auth.vector, vector, AUTH_VECTOR_LEN); |
359 |
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total_length = AUTH_HDR_LEN; |
360 |
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ptr = auth.data; |
361 |
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|
362 |
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/* User name */ |
363 |
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*ptr++ = PW_USER_NAME; |
364 |
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length = strlen(name); |
365 |
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if (length > MAXPWNETNAM) |
366 |
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length = MAXPWNETNAM; |
367 |
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*ptr++ = length + 2; |
368 |
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memcpy(ptr, name, length); |
369 |
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ptr += length; |
370 |
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total_length += length + 2; |
371 |
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|
372 |
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/* Password */ |
373 |
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length = strlen(password); |
374 |
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if (length > AUTH_PASS_LEN) |
375 |
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length = AUTH_PASS_LEN; |
376 |
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|
377 |
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p = (length + AUTH_VECTOR_LEN - 1) / AUTH_VECTOR_LEN; |
378 |
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*ptr++ = PW_PASSWORD; |
379 |
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*ptr++ = p * AUTH_VECTOR_LEN + 2; |
380 |
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|
381 |
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memset(pass_buf, 0, sizeof(pass_buf)); /* must zero fill */ |
382 |
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strlcpy((char *)pass_buf, password, sizeof(pass_buf)); |
383 |
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|
384 |
|
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/* Calculate the md5 digest */ |
385 |
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secretlen = strlen(auth_secret); |
386 |
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memcpy(md5buf, auth_secret, secretlen); |
387 |
|
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memcpy(md5buf + secretlen, auth.vector, AUTH_VECTOR_LEN); |
388 |
|
|
|
389 |
|
|
total_length += 2; |
390 |
|
|
|
391 |
|
|
/* XOR the password into the md5 digest */ |
392 |
|
|
pw = pass_buf; |
393 |
|
|
while (p-- > 0) { |
394 |
|
|
MD5Init(&context); |
395 |
|
|
MD5Update(&context, md5buf, secretlen + AUTH_VECTOR_LEN); |
396 |
|
|
MD5Final(digest, &context); |
397 |
|
|
for (i = 0; i < AUTH_VECTOR_LEN; ++i) { |
398 |
|
|
*ptr = digest[i] ^ *pw; |
399 |
|
|
md5buf[secretlen+i] = *ptr++; |
400 |
|
|
*pw++ = '\0'; |
401 |
|
|
} |
402 |
|
|
total_length += AUTH_VECTOR_LEN; |
403 |
|
|
} |
404 |
|
|
explicit_bzero(pass_buf, strlen(pass_buf)); |
405 |
|
|
|
406 |
|
|
/* Client id */ |
407 |
|
|
*ptr++ = PW_CLIENT_ID; |
408 |
|
|
*ptr++ = sizeof(in_addr_t) + 2; |
409 |
|
|
ipaddr = gethost(); |
410 |
|
|
memcpy(ptr, &ipaddr, sizeof(in_addr_t)); |
411 |
|
|
ptr += sizeof(in_addr_t); |
412 |
|
|
total_length += sizeof(in_addr_t) + 2; |
413 |
|
|
|
414 |
|
|
/* client port */ |
415 |
|
|
*ptr++ = PW_CLIENT_PORT_ID; |
416 |
|
|
*ptr++ = sizeof(in_addr_t) + 2; |
417 |
|
|
port = htonl(port); |
418 |
|
|
memcpy(ptr, &port, sizeof(int)); |
419 |
|
|
ptr += sizeof(int); |
420 |
|
|
total_length += sizeof(int) + 2; |
421 |
|
|
|
422 |
|
|
/* Append the state info */ |
423 |
|
|
if ((state != NULL) && (strlen(state) > 0)) { |
424 |
|
|
len = strlen(state); |
425 |
|
|
*ptr++ = PW_STATE; |
426 |
|
|
*ptr++ = len + 2; |
427 |
|
|
memcpy(ptr, state, len); |
428 |
|
|
ptr += len; |
429 |
|
|
total_length += len + 2; |
430 |
|
|
} |
431 |
|
|
|
432 |
|
|
auth.length = htons(total_length); |
433 |
|
|
|
434 |
|
|
memset(&sin, 0, sizeof (sin)); |
435 |
|
|
sin.sin_family = AF_INET; |
436 |
|
|
sin.sin_addr.s_addr = auth_server; |
437 |
|
|
sin.sin_port = radius_port; |
438 |
|
|
if (sendto(sockfd, &auth, total_length, 0, (struct sockaddr *)&sin, |
439 |
|
|
sizeof(sin)) == -1) |
440 |
|
|
err(1, NULL); |
441 |
|
|
} |
442 |
|
|
|
443 |
|
|
/* |
444 |
|
|
* Receive UDP responses from the radius server |
445 |
|
|
*/ |
446 |
|
|
int |
447 |
|
|
rad_recv(char *state, char *challenge, u_char *req_vector) |
448 |
|
|
{ |
449 |
|
|
auth_hdr_t auth; |
450 |
|
|
socklen_t salen; |
451 |
|
|
struct sockaddr_in sin; |
452 |
|
|
u_char recv_vector[AUTH_VECTOR_LEN], test_vector[AUTH_VECTOR_LEN]; |
453 |
|
|
MD5_CTX context; |
454 |
|
|
|
455 |
|
|
salen = sizeof(sin); |
456 |
|
|
|
457 |
|
|
alarm(timeout); |
458 |
|
|
if ((recvfrom(sockfd, &auth, sizeof(auth), 0, |
459 |
|
|
(struct sockaddr *)&sin, &salen)) < AUTH_HDR_LEN) { |
460 |
|
|
if (timedout) |
461 |
|
|
return(-1); |
462 |
|
|
errx(1, "bogus auth packet from server"); |
463 |
|
|
} |
464 |
|
|
alarm(0); |
465 |
|
|
|
466 |
|
|
if (sin.sin_addr.s_addr != auth_server) |
467 |
|
|
errx(1, "bogus authentication server"); |
468 |
|
|
|
469 |
|
|
/* verify server's shared secret */ |
470 |
|
|
memcpy(recv_vector, auth.vector, AUTH_VECTOR_LEN); |
471 |
|
|
memcpy(auth.vector, req_vector, AUTH_VECTOR_LEN); |
472 |
|
|
MD5Init(&context); |
473 |
|
|
MD5Update(&context, (u_char *)&auth, ntohs(auth.length)); |
474 |
|
|
MD5Update(&context, auth_secret, strlen(auth_secret)); |
475 |
|
|
MD5Final(test_vector, &context); |
476 |
|
|
if (memcmp(recv_vector, test_vector, AUTH_VECTOR_LEN) != 0) |
477 |
|
|
errx(1, "shared secret incorrect"); |
478 |
|
|
|
479 |
|
|
if (auth.code == PW_ACCESS_CHALLENGE) |
480 |
|
|
parse_challenge(&auth, state, challenge); |
481 |
|
|
|
482 |
|
|
return (auth.code); |
483 |
|
|
} |
484 |
|
|
|
485 |
|
|
/* |
486 |
|
|
* Get IP address of local hostname |
487 |
|
|
*/ |
488 |
|
|
in_addr_t |
489 |
|
|
gethost(void) |
490 |
|
|
{ |
491 |
|
|
char hostname[HOST_NAME_MAX+1]; |
492 |
|
|
|
493 |
|
|
if (gethostname(hostname, sizeof(hostname))) |
494 |
|
|
err(1, "gethost"); |
495 |
|
|
return (get_ipaddr(hostname)); |
496 |
|
|
} |
497 |
|
|
|
498 |
|
|
/* |
499 |
|
|
* Get an IP address in host in_addr_t notation from a hostname or dotted quad. |
500 |
|
|
*/ |
501 |
|
|
in_addr_t |
502 |
|
|
get_ipaddr(char *host) |
503 |
|
|
{ |
504 |
|
|
struct hostent *hp; |
505 |
|
|
|
506 |
|
|
if ((hp = gethostbyname(host)) == NULL) |
507 |
|
|
return (0); |
508 |
|
|
|
509 |
|
|
return (((struct in_addr *)hp->h_addr)->s_addr); |
510 |
|
|
} |
511 |
|
|
|
512 |
|
|
/* |
513 |
|
|
* Get the secret from the servers file |
514 |
|
|
*/ |
515 |
|
|
void |
516 |
|
|
getsecret(void) |
517 |
|
|
{ |
518 |
|
|
FILE *servfd; |
519 |
|
|
char *host, *secret, buffer[PATH_MAX]; |
520 |
|
|
size_t len; |
521 |
|
|
|
522 |
|
|
snprintf(buffer, sizeof(buffer), "%s/%s", |
523 |
|
|
radius_dir, RADIUS_SERVERS); |
524 |
|
|
|
525 |
|
|
if ((servfd = fopen(buffer, "r")) == NULL) { |
526 |
|
|
syslog(LOG_ERR, "%s: %m", buffer); |
527 |
|
|
return; |
528 |
|
|
} |
529 |
|
|
|
530 |
|
|
secret = NULL; /* Keeps gcc happy */ |
531 |
|
|
while ((host = fgetln(servfd, &len)) != NULL) { |
532 |
|
|
if (*host == '#') { |
533 |
|
|
memset(host, 0, len); |
534 |
|
|
continue; |
535 |
|
|
} |
536 |
|
|
if (host[len-1] == '\n') |
537 |
|
|
--len; |
538 |
|
|
else { |
539 |
|
|
/* No trailing newline, must allocate len+1 for NUL */ |
540 |
|
|
if ((secret = malloc(len + 1)) == NULL) { |
541 |
|
|
memset(host, 0, len); |
542 |
|
|
continue; |
543 |
|
|
} |
544 |
|
|
memcpy(secret, host, len); |
545 |
|
|
memset(host, 0, len); |
546 |
|
|
host = secret; |
547 |
|
|
} |
548 |
|
|
while (len > 0 && isspace((unsigned char)host[--len])) |
549 |
|
|
; |
550 |
|
|
host[++len] = '\0'; |
551 |
|
|
while (isspace((unsigned char)*host)) { |
552 |
|
|
++host; |
553 |
|
|
--len; |
554 |
|
|
} |
555 |
|
|
if (*host == '\0') |
556 |
|
|
continue; |
557 |
|
|
secret = host; |
558 |
|
|
while (*secret && !isspace((unsigned char)*secret)) |
559 |
|
|
++secret; |
560 |
|
|
if (*secret) |
561 |
|
|
*secret++ = '\0'; |
562 |
|
|
if (get_ipaddr(host) != auth_server) { |
563 |
|
|
memset(host, 0, len); |
564 |
|
|
continue; |
565 |
|
|
} |
566 |
|
|
while (isspace((unsigned char)*secret)) |
567 |
|
|
++secret; |
568 |
|
|
if (*secret) |
569 |
|
|
break; |
570 |
|
|
} |
571 |
|
|
if (host) { |
572 |
|
|
strlcpy(auth_secret, secret, sizeof(auth_secret)); |
573 |
|
|
memset(host, 0, len); |
574 |
|
|
} |
575 |
|
|
fclose(servfd); |
576 |
|
|
} |
577 |
|
|
|
578 |
|
|
void |
579 |
|
|
servtimeout(int signo) |
580 |
|
|
{ |
581 |
|
|
|
582 |
|
|
timedout = 1; |
583 |
|
|
} |
584 |
|
|
|
585 |
|
|
/* |
586 |
|
|
* Parse a challenge received from the server |
587 |
|
|
*/ |
588 |
|
|
void |
589 |
|
|
parse_challenge(auth_hdr_t *authhdr, char *state, char *challenge) |
590 |
|
|
{ |
591 |
|
|
int length; |
592 |
|
|
int attribute, attribute_len; |
593 |
|
|
u_char *ptr; |
594 |
|
|
|
595 |
|
|
ptr = authhdr->data; |
596 |
|
|
length = ntohs(authhdr->length) - AUTH_HDR_LEN; |
597 |
|
|
|
598 |
|
|
*state = 0; |
599 |
|
|
|
600 |
|
|
while (length > 0) { |
601 |
|
|
attribute = *ptr++; |
602 |
|
|
attribute_len = *ptr++; |
603 |
|
|
length -= attribute_len; |
604 |
|
|
attribute_len -= 2; |
605 |
|
|
|
606 |
|
|
switch (attribute) { |
607 |
|
|
case PW_PORT_MESSAGE: |
608 |
|
|
if (challenge) { |
609 |
|
|
memcpy(challenge, ptr, attribute_len); |
610 |
|
|
challenge[attribute_len] = '\0'; |
611 |
|
|
} else |
612 |
|
|
printf("%.*s", attribute_len, ptr); |
613 |
|
|
break; |
614 |
|
|
case PW_STATE: |
615 |
|
|
memcpy(state, ptr, attribute_len); |
616 |
|
|
state[attribute_len] = '\0'; |
617 |
|
|
break; |
618 |
|
|
} |
619 |
|
|
ptr += attribute_len; |
620 |
|
|
} |
621 |
|
|
} |