/*      $NetBSD: as.c,v 1.1 2001/11/04 23:14:36 atatat Exp $    */

/*
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Andrew Brown.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <err.h>
#include <stdio.h>

#include "as.h"

#define DEFAULT_AS_SERVER "whois.radb.net"
#undef AS_DEBUG_FILE

struct aslookup {
        FILE *as_f;
#ifdef AS_DEBUG_FILE
        FILE *as_debug;
#endif /* AS_DEBUG_FILE */
};

void *
as_setup(const char *server)
{
        struct aslookup *asn;
        struct addrinfo hints, *res0, *res;
        FILE *f;
        int s, error;

        s = -1;
        if (server == NULL)
                server = getenv("RA_SERVER");
        if (server == NULL)
                server = DEFAULT_AS_SERVER;

        memset(&hints, 0, sizeof(hints));
        hints.ai_family = PF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        error = getaddrinfo(server, "whois", &hints, &res0);
        if (error == EAI_SERVICE) {
                warnx("warning: whois/tcp service not found");
                error = getaddrinfo(server, "43", &hints, &res0);
        }
        if (error != 0) {
                warnx("%s: %s", server, gai_strerror(error));
                return (NULL);
        }

        for (res = res0; res; res = res->ai_next) {
                s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
                if (s < 0)
                        continue;
                if (connect(s, res->ai_addr, res->ai_addrlen) >= 0)
                        break;
                close(s);
                s = -1;
        }
        freeaddrinfo(res0);
        if (s < 0) {
                warn("connect");
                return (NULL);
        }

        f = fdopen(s, "r+");
        (void)fprintf(f, "!!\n");
        (void)fflush(f);

        asn = malloc(sizeof(struct aslookup));
        if (asn == NULL)
                (void)fclose(f);
        else
                asn->as_f = f;

#ifdef AS_DEBUG_FILE
        asn->as_debug = fopen(AS_DEBUG_FILE, "w");
        if (asn->as_debug) {
                (void)fprintf(asn->as_debug, ">> !!\n");
                (void)fflush(asn->as_debug);
        }
#endif /* AS_DEBUG_FILE */

        return (asn);
}

unsigned int
as_lookup(void *_asn, char *addr, sa_family_t family, int *status)
{
        struct aslookup *asn = _asn;
        char buf[1024];
        unsigned int as;
        int rc, dlen, plen;

        as = 0;
        rc = dlen = 0;
        plen = (family == AF_INET6) ? 128 : 32;
        *status = fprintf(asn->as_f, "!r%s/%d,l\n", addr, plen);
        if (*status < 0) {
                *status = errno;
                return 0;
        }
        *status = fflush(asn->as_f);
        if (*status == EOF) {
                *status = errno;
                return 0;
        }
        *status = 0;

#ifdef AS_DEBUG_FILE
        if (asn->as_debug) {
                (void)fprintf(asn->as_debug, ">> !r%s/%d,l\n", addr, plen);
                (void)fflush(asn->as_debug);
        }
#endif /* AS_DEBUG_FILE */

        while (1) {
                if (fgets(buf, sizeof(buf), asn->as_f) == NULL) {
                        if(feof(asn->as_f) || ferror(asn->as_f)) {
                                *status = EIO;
                                return 0;
                        }
                        break;
                }
                buf[sizeof(buf) - 1] = '\0';

#ifdef AS_DEBUG_FILE
                if (asn->as_debug) {
                        (void)fprintf(asn->as_debug, "<< %s", buf);
                        (void)fflush(asn->as_debug);
                }
#endif /* AS_DEBUG_FILE */

                if (rc == 0) {
                        rc = buf[0];
                        switch (rc) {
                            case 'A':
                                /* A - followed by # bytes of answer */
                                sscanf(buf, "A%d\n", &dlen);
#ifdef AS_DEBUG_FILE
                                if (asn->as_debug) {
                                        (void)fprintf(asn->as_debug,
                                             "dlen: %d\n", dlen);
                                        (void)fflush(asn->as_debug);
                                }
#endif /* AS_DEBUG_FILE */
                                break;
                            case 'C':
                            case 'D':
                            case 'E':
                            case 'F':
                                /* C - no data returned */
                                /* D - key not found */
                                /* E - multiple copies of key */
                                /* F - some other error */
                                break;
                        }
                        if (rc == 'A')
                                /* skip to next input line */
                                continue;
                }

                if (dlen == 0)
                        /* out of data, next char read is end code */
                        rc = buf[0];
                if (rc != 'A')
                        /* either an error off the bat, or a done code */
                        break;

                /* data received, thank you */
                dlen -= strlen(buf);

                /* origin line is the interesting bit */
                if (as == 0 && strncasecmp(buf, "origin:", 7) == 0) {
                        sscanf(buf + 7, " AS%u", &as);
#ifdef AS_DEBUG_FILE
                        if (asn->as_debug) {
                                (void)fprintf(asn->as_debug, "as: %d\n", as);
                                (void)fflush(asn->as_debug);
                        }
#endif /* AS_DEBUG_FILE */
                }
        }

        return (as);
}

void
as_shutdown(void *_asn)
{
        struct aslookup *asn = _asn;

        (void)fprintf(asn->as_f, "!q\n");
        (void)fclose(asn->as_f);

#ifdef AS_DEBUG_FILE
        if (asn->as_debug) {
                (void)fprintf(asn->as_debug, ">> !q\n");
                (void)fclose(asn->as_debug);
        }
#endif /* AS_DEBUG_FILE */

        free(asn);
}