/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (c) 1996,1998 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/* Imports. */

#include "port_before.h"

#include <syslog.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>

#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>

#include <irs.h>
#include <irp.h>
#include <isc/irpmarshall.h>
#include <isc/memcluster.h>

#include "irs_p.h"
#include "dns_p.h"
#include "irp_p.h"

#include "port_after.h"

/* Definitions. */

#define MAXALIASES      35
#define MAXADDRS        35
#define Max(a,b)        ((a) > (b) ? (a) : (b))


struct pvt {
        struct irp_p           *girpdata;
        int                     warned;
        struct hostent          host;
};

/* Forward. */

static void             ho_close(struct irs_ho *this);
static struct hostent * ho_byname(struct irs_ho *this, const char *name);
static struct hostent * ho_byname2(struct irs_ho *this, const char *name,
                                   int af);
static struct hostent * ho_byaddr(struct irs_ho *this, const void *addr,
                                  int len, int af);
static struct hostent * ho_next(struct irs_ho *this);
static void             ho_rewind(struct irs_ho *this);
static void             ho_minimize(struct irs_ho *this);

static void             free_host(struct hostent *ho);
static struct addrinfo * ho_addrinfo(struct irs_ho *this, const char *name,
                                     const struct addrinfo *pai);

/* Public. */

/*%
 * struct irs_ho * irs_irp_ho(struct irs_acc *this)
 *
 * Notes:
 *
 *      Initializes the irp_ho module.
 *
 */

struct irs_ho *
irs_irp_ho(struct irs_acc *this) {
        struct irs_ho *ho;
        struct pvt *pvt;

        if (!(ho = memget(sizeof *ho))) {
                errno = ENOMEM;
                return (NULL);
        }
        memset(ho, 0x0, sizeof *ho);

        if (!(pvt = memget(sizeof *pvt))) {
                memput(ho, sizeof *ho);
                errno = ENOMEM;
                return (NULL);
        }
        memset(pvt, 0, sizeof *pvt);
        pvt->girpdata = this->private;

        ho->private = pvt;
        ho->close = ho_close;
        ho->byname = ho_byname;
        ho->byname2 = ho_byname2;
        ho->byaddr = ho_byaddr;
        ho->next = ho_next;
        ho->rewind = ho_rewind;
        ho->minimize = ho_minimize;
        ho->addrinfo = ho_addrinfo;

        return (ho);
}

/* Methods. */

/*%
 *      Closes down the module.
 *
 */

static void
ho_close(struct irs_ho *this) {
        struct pvt *pvt = (struct pvt *)this->private;

        ho_minimize(this);

        free_host(&pvt->host);

        memput(pvt, sizeof *pvt);
        memput(this, sizeof *this);
}



/*
 * struct hostent * ho_byname(struct irs_ho *this, const char *name)
 *
 */

static struct hostent *
ho_byname(struct irs_ho *this, const char *name) {
        return (ho_byname2(this, name, AF_INET));
}





/*
 * struct hostent * ho_byname2(struct irs_ho *this, const char *name, int af)
 *
 */

static struct hostent *
ho_byname2(struct irs_ho *this, const char *name, int af) {
        struct pvt *pvt = (struct pvt *)this->private;
        struct hostent *ho = &pvt->host;
        char *body = NULL;
        size_t bodylen;
        int code;
        char text[256];

        if (ho->h_name != NULL &&
            strcmp(name, ho->h_name) == 0 &&
            af == ho->h_addrtype) {
                return (ho);
        }

        if (irs_irp_connection_setup(pvt->girpdata, &pvt->warned) != 0) {
                return (NULL);
        }

        if (irs_irp_send_command(pvt->girpdata, "gethostbyname2 %s %s",
                                 name, ADDR_T_STR(af)) != 0)
                return (NULL);

        if (irs_irp_get_full_response(pvt->girpdata, &code,
                                      text, sizeof text,
                                      &body, &bodylen) != 0) {
                return (NULL);
        }

        if (code == IRPD_GETHOST_OK) {
                free_host(ho);
                if (irp_unmarshall_ho(ho, body) != 0) {
                        ho = NULL;
                }
        } else {
                ho = NULL;
        }

        if (body != NULL) {
                memput(body, bodylen);
        }

        return (ho);
}



/*
 * struct hostent * ho_byaddr(struct irs_ho *this, const void *addr,
 *                         int len, int af)
 *
 */

static struct hostent *
ho_byaddr(struct irs_ho *this, const void *addr, int len, int af) {
        struct pvt *pvt = (struct pvt *)this->private;
        struct hostent *ho = &pvt->host;
        char *body = NULL;
        size_t bodylen;
        int code;
        char **p;
        char paddr[MAXPADDRSIZE];
        char text[256];

        if (ho->h_name != NULL &&
            af == ho->h_addrtype &&
            len == ho->h_length) {
                for (p = ho->h_addr_list ; *p != NULL ; p++) {
                        if (memcmp(*p, addr, len) == 0)
                                return (ho);
                }
        }

        if (irs_irp_connection_setup(pvt->girpdata, &pvt->warned) != 0) {
                return (NULL);
        }

        if (inet_ntop(af, addr, paddr, sizeof paddr) == NULL) {
                return (NULL);
        }

        if (irs_irp_send_command(pvt->girpdata, "gethostbyaddr %s %s",
                                 paddr, ADDR_T_STR(af)) != 0) {
                return (NULL);
        }

        if (irs_irp_get_full_response(pvt->girpdata, &code,
                                      text, sizeof text,
                                      &body, &bodylen) != 0) {
                return (NULL);
        }

        if (code == IRPD_GETHOST_OK) {
                free_host(ho);
                if (irp_unmarshall_ho(ho, body) != 0) {
                        ho = NULL;
                }
        } else {
                ho = NULL;
        }

        if (body != NULL) {
                memput(body, bodylen);
        }

        return (ho);
}

/*%
 *      The implementation for gethostent(3). The first time it's
 *      called all the data is pulled from the remote(i.e. what
 *      the maximum number of gethostent(3) calls would return)
 *      and that data is cached.
 *
 */

static struct hostent *
ho_next(struct irs_ho *this) {
        struct pvt *pvt = (struct pvt *)this->private;
        struct hostent *ho = &pvt->host;
        char *body;
        size_t bodylen;
        int code;
        char text[256];

        if (irs_irp_connection_setup(pvt->girpdata, &pvt->warned) != 0) {
                return (NULL);
        }

        if (irs_irp_send_command(pvt->girpdata, "gethostent") != 0) {
                return (NULL);
        }

        if (irs_irp_get_full_response(pvt->girpdata, &code,
                                      text, sizeof text,
                                      &body, &bodylen) != 0) {
                return (NULL);
        }

        if (code == IRPD_GETHOST_OK) {
                free_host(ho);
                if (irp_unmarshall_ho(ho, body) != 0) {
                        ho = NULL;
                }
        } else {
                ho = NULL;
        }

        if (body != NULL) {
                memput(body, bodylen);
        }

        return (ho);
}

/*%
 * void ho_rewind(struct irs_ho *this)
 *
 */

static void
ho_rewind(struct irs_ho *this) {
        struct pvt *pvt = (struct pvt *)this->private;
        char text[256];
        int code;

        if (irs_irp_connection_setup(pvt->girpdata, &pvt->warned) != 0) {
                return;
        }

        if (irs_irp_send_command(pvt->girpdata, "sethostent") != 0) {
                return;
        }

        code = irs_irp_read_response(pvt->girpdata, text, sizeof text);
        if (code != IRPD_GETHOST_SETOK) {
                if (irp_log_errors) {
                        syslog(LOG_WARNING, "sethostent failed: %s", text);
                }
        }

        return;
}

/*%
 * void ho_minimize(struct irs_ho *this)
 *
 */

static void
ho_minimize(struct irs_ho *this) {
        struct pvt *pvt = (struct pvt *)this->private;

        free_host(&pvt->host);

        irs_irp_disconnect(pvt->girpdata);
}

/*%
 * void free_host(struct hostent *ho)
 *
 */

static void
free_host(struct hostent *ho) {
        char **p;

        if (ho == NULL) {
                return;
        }

        if (ho->h_name != NULL)
                free(ho->h_name);

        if (ho->h_aliases != NULL) {
                for (p = ho->h_aliases ; *p != NULL ; p++)
                        free(*p);
                free(ho->h_aliases);
        }

        if (ho->h_addr_list != NULL) {
                for (p = ho->h_addr_list ; *p != NULL ; p++)
                        free(*p);
                free(ho->h_addr_list);
        }
}

/* dummy */
static struct addrinfo *
ho_addrinfo(struct irs_ho *this, const char *name, const struct addrinfo *pai)
{
        UNUSED(this);
        UNUSED(name);
        UNUSED(pai);
        return(NULL);
}

/*! \file */