/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 1998, 2001, Juniper Networks, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */

#ifndef TACLIB_PRIVATE_H
#define TACLIB_PRIVATE_H

#include "taclib.h"

/* Defaults */
#define PATH_TACPLUS_CONF       "/etc/tacplus.conf"
#define TACPLUS_PORT            49
#define TIMEOUT                 3       /* In seconds */

/* Limits */
#define BODYSIZE        8150            /* Maximum message body size */
#define ERRSIZE         128             /* Maximum error message length */
#define MAXCONFLINE     1024            /* Maximum config file line length */
#define MAXSERVERS      10              /* Maximum number of servers to try */
#define MAXAVPAIRS      255             /* Maximum number of AV pairs */

/* Protocol constants. */
#define HDRSIZE         12              /* Size of message header */

/* Protocol version number */
#define TAC_VER_MAJOR           0xc             /* Major version number */

/* Protocol packet types */
#define TAC_AUTHEN              0x01            /* Authentication */
#define TAC_AUTHOR              0x02            /* Authorization */
#define TAC_ACCT                0x03            /* Accouting */

/* Protocol header flags */
#define TAC_UNENCRYPTED         0x01
#define TAC_SINGLE_CONNECT      0x04

struct tac_str {
        char            *data;
        size_t           len;
};

struct tac_authen_start {
        u_int8_t        action;
        u_int8_t        priv_lvl;
        u_int8_t        authen_type;
        u_int8_t        service;
        u_int8_t        user_len;
        u_int8_t        port_len;
        u_int8_t        rem_addr_len;
        u_int8_t        data_len;
        unsigned char   rest[1];
};

struct tac_authen_reply {
        u_int8_t        status;
        u_int8_t        flags;
        u_int16_t       msg_len;
        u_int16_t       data_len;
        unsigned char   rest[1];
};

struct tac_authen_cont {
        u_int16_t       user_msg_len;
        u_int16_t       data_len;
        u_int8_t        flags;
        unsigned char   rest[1];
};

struct tac_author_request {
        u_int8_t        authen_meth;
        u_int8_t        priv_lvl;
        u_int8_t        authen_type;
        u_int8_t        service;
        u_int8_t        user_len;
        u_int8_t        port_len;
        u_int8_t        rem_addr_len;
        u_int8_t        av_cnt;
        unsigned char   rest[1];
};

struct tac_author_response {
        u_int8_t        status;
        u_int8_t        av_cnt;
        u_int16_t       msg_len;
        u_int16_t       data_len;
        unsigned char   rest[1];
};

struct tac_acct_start {
        u_int8_t        action;
        u_int8_t        authen_action;
        u_int8_t        priv_lvl;
        u_int8_t        authen_type;
        u_int8_t        authen_service;
        u_int8_t        user_len;
        u_int8_t        port_len;
        u_int8_t        rem_addr_len;
        u_int8_t        av_cnt;
        unsigned char   rest[1];
};

struct tac_acct_reply {
        u_int16_t       msg_len;
        u_int16_t       data_len;
        u_int8_t        status;
        unsigned char   rest[1];
};

struct tac_msg {
        u_int8_t        version;
        u_int8_t        type;
        u_int8_t        seq_no;
        u_int8_t        flags;
        u_int8_t        session_id[4];
        u_int32_t       length;
        union {
                struct tac_authen_start authen_start;
                struct tac_authen_reply authen_reply;
                struct tac_authen_cont authen_cont;
                struct tac_author_request author_request;
                struct tac_author_response author_response;
                struct tac_acct_start acct_start;
                struct tac_acct_reply acct_reply;
                unsigned char body[BODYSIZE];
        } u;
};

struct tac_server {
        struct sockaddr_in addr;        /* Address of server */
        char            *secret;        /* Shared secret */
        int              timeout;       /* Timeout in seconds */
        int              flags;
        unsigned int     navs;
        struct tac_str   avs[MAXAVPAIRS];
};

struct tac_handle {
        int              fd;            /* Socket file descriptor */
        struct tac_server servers[MAXSERVERS];  /* Servers to contact */
        int              num_servers;   /* Number of valid server entries */
        int              cur_server;    /* Server we are currently using */
        int              single_connect;        /* Use a single connection */
        int              last_seq_no;
        char             errmsg[ERRSIZE];       /* Most recent error message */

        struct tac_str   user;
        struct tac_str   port;
        struct tac_str   rem_addr;
        struct tac_str   data;
        struct tac_str   user_msg;
        struct tac_str   avs[MAXAVPAIRS];

        struct tac_msg   request;
        struct tac_msg   response;

        int              srvr_pos;      /* Scan position in response body */
        unsigned int     srvr_navs;
        struct tac_str   srvr_msg;
        struct tac_str   srvr_data;
        struct tac_str   srvr_avs[MAXAVPAIRS];
};

#define is_alpha(ch) /* alphabetical */                                 \
        (((ch) >= 'A' && (ch) <= 'Z') || ((ch) >= 'a' && (ch) <= 'z'))
#define is_num(ch) /* numerical */                                      \
        ((ch) >= '0' && (ch) <= '9')
#define is_alnum(ch) /* alphanumerical */                               \
        (is_alpha(ch) || is_num(ch))
#define is_arg(ch) /* valid in an argument name */                      \
        (is_alnum(ch) || (ch) == '_' || (ch) == '-')

#endif