/*
 * Copyright (C) 2012 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 */

#include <ctype.h>

#include "ipf.h"
#include "ipt.h"


extern  int     opts;

static  int     hex_open(char *);
static  int     hex_close(void);
static  int     hex_readip(mb_t *, char **, int *);
static  char    *readhex(char *, char *);

struct  ipread  iphex = { hex_open, hex_close, hex_readip, 0 };
static  FILE    *tfp = NULL;
static  int     tfd = -1;

static int
hex_open(char *fname)
{
        if (tfp && tfd != -1) {
                rewind(tfp);
                return (tfd);
        }

        if (!strcmp(fname, "-")) {
                tfd = 0;
                tfp = stdin;
        } else {
                tfd = open(fname, O_RDONLY);
                if (tfd != -1)
                        tfp = fdopen(tfd, "r");
        }
        return (tfd);
}


static int
hex_close(void)
{
        int     cfd = tfd;

        tfd = -1;
        return (close(cfd));
}


static int
hex_readip(mb_t *mb, char **ifn, int *dir)
{
        register char *s, *t, *u;
        char    line[513];
        ip_t    *ip;
        char    *buf;

        buf = (char *)mb->mb_buf;
        /*
         * interpret start of line as possibly "[ifname]" or
         * "[in/out,ifname]".
         */
        if (ifn)
                *ifn = NULL;
        if (dir)
                *dir = 0;
        ip = (ip_t *)buf;
        while (fgets(line, sizeof(line)-1, tfp)) {
                if ((s = strchr(line, '\n'))) {
                        if (s == line) {
                                mb->mb_len = (char *)ip - buf;
                                return (mb->mb_len);
                        }
                        *s = '\0';
                }
                if ((s = strchr(line, '#')))
                        *s = '\0';
                if (!*line)
                        continue;
                if ((opts & OPT_DEBUG) != 0) {
                        printf("input: %s", line);
                }

                if ((*line == '[') && (s = strchr(line, ']'))) {
                        t = line + 1;
                        if (s - t > 0) {
                                *s++ = '\0';
                                if ((u = strchr(t, ',')) && (u < s)) {
                                        u++;
                                        if (ifn)
                                                *ifn = strdup(u);
                                        if (dir) {
                                                if (*t == 'i')
                                                        *dir = 0;
                                                else if (*t == 'o')
                                                        *dir = 1;
                                        }
                                } else if (ifn)
                                        *ifn = t;
                        }

                        while (*s++ == '+') {
                                if (!strncasecmp(s, "mcast", 5)) {
                                        mb->mb_flags |= M_MCAST;
                                        s += 5;
                                }
                                if (!strncasecmp(s, "bcast", 5)) {
                                        mb->mb_flags |= M_BCAST;
                                        s += 5;
                                }
                                if (!strncasecmp(s, "mbcast", 6)) {
                                        mb->mb_flags |= M_MBCAST;
                                        s += 6;
                                }
                        }
                        while (ISSPACE(*s))
                                s++;
                } else
                        s = line;
                t = (char *)ip;
                ip = (ip_t *)readhex(s, (char *)ip);
                if ((opts & OPT_DEBUG) != 0) {
                        if (opts & OPT_ASCII) {
                                int c = *t;
                                if (t < (char *)ip)
                                        putchar('\t');
                                while (t < (char *)ip) {
                                        if (isprint(c) && isascii(c))
                                                putchar(c);
                                        else
                                                putchar('.');
                                        t++;
                                }
                        }
                        putchar('\n');
                        fflush(stdout);
                }
        }
        if (feof(tfp))
                return (0);
        return (-1);
}


static char
*readhex(register char *src, register char *dst)
{
        int     state = 0;
        char    c;

        while ((c = *src++)) {
                if (ISSPACE(c)) {
                        if (state) {
                                dst++;
                                state = 0;
                        }
                        continue;
                } else if ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') ||
                           (c >= 'A' && c <= 'F')) {
                        c = ISDIGIT(c) ? (c - '0') : (TOUPPER(c) - 55);
                        if (state == 0) {
                                *dst = (c << 4);
                                state++;
                        } else {
                                *dst++ |= c;
                                state = 0;
                        }
                } else
                        break;
        }
        return (dst);
}