/*      $NetBSD: getaddrinfo.c,v 1.4 2014/04/22 02:23:03 ginsbach Exp $ */

/*-
 * Copyright (c) 2013 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Taylor R. Campbell.
 *
 * 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/types.h>
#include <sys/socket.h>

#include <assert.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <netdb.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <util.h>

#include "tables.h"

static void     usage(void) __dead;
static void     printaddrinfo(struct addrinfo *);
static bool     parse_af(const char *, int *);
static bool     parse_protocol(const char *, int *);
static bool     parse_socktype(const char *, int *);
static bool     parse_numeric_tabular(const char *, int *, const char *const *,
                    size_t);

int
main(int argc, char **argv)
{
        static const struct addrinfo zero_addrinfo;
        struct addrinfo hints = zero_addrinfo;
        struct addrinfo *addrinfo;
        const char *hostname = NULL, *service = NULL;
        int ch;
        int error;

        setprogname(argv[0]);

        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = 0;
        hints.ai_protocol = 0;
        hints.ai_flags = 0;

        while ((ch = getopt(argc, argv, "cf:nNp:Ps:t:")) != -1) {
                switch (ch) {
                case 'c':
                        hints.ai_flags |= AI_CANONNAME;
                        break;

                case 'f':
                        if (!parse_af(optarg, &hints.ai_family)) {
                                warnx("invalid address family: %s", optarg);
                                usage();
                        }
                        break;

                case 'n':
                        hints.ai_flags |= AI_NUMERICHOST;
                        break;

                case 'N':
                        hints.ai_flags |= AI_NUMERICSERV;
                        break;

                case 's':
                        service = optarg;
                        break;

                case 'p':
                        if (!parse_protocol(optarg, &hints.ai_protocol)) {
                                warnx("invalid protocol: %s", optarg);
                                usage();
                        }
                        break;

                case 'P':
                        hints.ai_flags |= AI_PASSIVE;
                        break;

                case 't':
                        if (!parse_socktype(optarg, &hints.ai_socktype)) {
                                warnx("invalid socket type: %s", optarg);
                                usage();
                        }
                        break;

                case '?':
                default:
                        usage();
                }
        }

        argc -= optind;
        argv += optind;

        if (!((argc == 1) || ((argc == 0) && (hints.ai_flags & AI_PASSIVE))))
                usage();
        if (argc == 1)
                hostname = argv[0];

        if (service != NULL) {
                char *p;

                if ((p = strchr(service, '/')) != NULL) {
                        if (hints.ai_protocol != 0) {
                                warnx("protocol already specified");
                                usage();
                        }
                        *p = '\0';
                        p++;

                        if (!parse_protocol(p, &hints.ai_protocol)) {
                                warnx("invalid protocol: %s", p);
                                usage();
                        }
                }
        }

        error = getaddrinfo(hostname, service, &hints, &addrinfo);
        if (error)
                errx(1, "%s", gai_strerror(error));

        if ((hints.ai_flags & AI_CANONNAME) && (addrinfo != NULL)) {
                if (printf("canonname %s\n", addrinfo->ai_canonname) < 0)
                        err(1, "printf");
        }

        printaddrinfo(addrinfo);

        freeaddrinfo(addrinfo);

        return 0;
}

static void __dead
usage(void)
{

        (void)fprintf(stderr, "Usage: %s", getprogname());
        (void)fprintf(stderr,
            " [-f <family>] [-p <protocol>] [-t <socktype>] [-s <service>]\n");
        (void)fprintf(stderr, "   [-cnNP] [<hostname>]\n");
        exit(1);
}

static bool
parse_af(const char *string, int *afp)
{

        return parse_numeric_tabular(string, afp, address_families,
            __arraycount(address_families));
}

static bool
parse_protocol(const char *string, int *protop)
{
        struct protoent *protoent;
        char *end;
        long value;

        errno = 0;
        value = strtol(string, &end, 0);
        if ((string[0] == '\0') || (*end != '\0'))
                goto numeric_failed;
        if ((errno == ERANGE) && ((value == LONG_MAX) || (value == LONG_MIN)))
                goto numeric_failed;
        if ((value > INT_MAX) || (value < INT_MIN))
                goto numeric_failed;

        *protop = value;
        return true;

numeric_failed:
        protoent = getprotobyname(string);
        if (protoent == NULL)
                goto protoent_failed;

        *protop = protoent->p_proto;
        return true;

protoent_failed:
        return false;
}

static bool
parse_socktype(const char *string, int *typep)
{

        return parse_numeric_tabular(string, typep, socket_types,
            __arraycount(socket_types));
}

static bool
parse_numeric_tabular(const char *string, int *valuep,
    const char *const *table, size_t n)
{
        char *end;
        long value;
        size_t i;

        assert((uintmax_t)n <= (uintmax_t)INT_MAX);

        errno = 0;
        value = strtol(string, &end, 0);
        if ((string[0] == '\0') || (*end != '\0'))
                goto numeric_failed;
        if ((errno == ERANGE) && ((value == LONG_MAX) || (value == LONG_MIN)))
                goto numeric_failed;
        if ((value > INT_MAX) || (value < INT_MIN))
                goto numeric_failed;

        *valuep = value;
        return true;

numeric_failed:
        for (i = 0; i < n; i++)
                if ((table[i] != NULL) && (strcmp(string, table[i]) == 0))
                        break;
        if (i == n)
                goto table_failed;
        *valuep = i;
        return true;

table_failed:
        return false;
}

static void
printaddrinfo(struct addrinfo *addrinfo)
{
        struct addrinfo *ai;
        char buf[1024];
        int n;
        struct protoent *protoent;

        for (ai = addrinfo; ai != NULL; ai = ai->ai_next) {
                /* Print the socket type.  */
                if ((ai->ai_socktype >= 0) &&
                    ((size_t)ai->ai_socktype < __arraycount(socket_types)) &&
                    (socket_types[ai->ai_socktype] != NULL))
                        n = printf("%s", socket_types[ai->ai_socktype]);
                else
                        n = printf("%d", ai->ai_socktype);
                if (n < 0)
                        err(1, "printf");

                /* Print the address family.  */
                if ((ai->ai_family >= 0) &&
                    ((size_t)ai->ai_family < __arraycount(address_families)) &&
                    (address_families[ai->ai_family] != NULL))
                        n = printf(" %s", address_families[ai->ai_family]);
                else
                        n = printf(" %d", ai->ai_family);
                if (n < 0)
                        err(1, "printf");

                /* Print the protocol number.  */
                protoent = getprotobynumber(ai->ai_protocol);
                if (protoent == NULL)
                        n = printf(" %d", ai->ai_protocol);
                else
                        n = printf(" %s", protoent->p_name);
                if (n < 0)
                        err(1, "printf");

                /* Format the sockaddr.  */
                switch (ai->ai_family) {
                case AF_INET:
                case AF_INET6:
                        n = sockaddr_snprintf(buf, sizeof(buf), " %a %p",
                            ai->ai_addr);
                        break;

                default:
                        n = sockaddr_snprintf(buf, sizeof(buf),
                            "%a %p %I %F %R %S", ai->ai_addr);
                }

                /*
                 * Check for sockaddr_snprintf failure.
                 *
                 * XXX sockaddr_snprintf's error reporting is botched
                 * -- man page says it sets errno, but if getnameinfo
                 * fails, errno is not where it reports the error...
                 */
                if (n < 0) {
                        warnx("sockaddr_snprintf failed");
                        continue;
                }
                if (sizeof(buf) <= (size_t)n)
                        warnx("truncated sockaddr_snprintf output");

                /* Print the formatted sockaddr.  */
                if (printf("%s\n", buf) < 0)
                        err(1, "printf");
        }
}