root/crypto/heimdal/lib/roken/socket_wrapper.c
/*
 * Copyright (C) Jelmer Vernooij 2005 <jelmer@samba.org>
 * Copyright (C) Stefan Metzmacher 2006 <metze@samba.org>
 *
 * 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.
 *
 * 3. Neither the name of the author nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * 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.
 *
 */

/*
   Socket wrapper library. Passes all socket communication over
   unix domain sockets if the environment variable SOCKET_WRAPPER_DIR
   is set.
*/

#define SOCKET_WRAPPER_NOT_REPLACE

#ifdef _SAMBA_BUILD_

#include "includes.h"
#include "system/network.h"
#include "system/filesys.h"

#ifdef malloc
#undef malloc
#endif
#ifdef calloc
#undef calloc
#endif
#ifdef strdup
#undef strdup
#endif

#else /* _SAMBA_BUILD_ */

#include <config.h>
#undef SOCKET_WRAPPER_REPLACE

#include <sys/types.h>
#ifdef TIME_WITH_SYS_TIME
#include <sys/time.h>
#include <time.h>
#elif defined(HAVE_SYS_TIME_H)
#include <sys/time.h>
#else
#include <time.h>
#endif
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#ifdef HAVE_SYS_FILIO_H
#include <sys/filio.h>
#endif
#include <errno.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include "roken.h"

#include "socket_wrapper.h"

#define HAVE_GETTIMEOFDAY_TZ 1

#define _PUBLIC_

#endif

#define SWRAP_DLIST_ADD(list,item) do { \
        if (!(list)) { \
                (item)->prev    = NULL; \
                (item)->next    = NULL; \
                (list)          = (item); \
        } else { \
                (item)->prev    = NULL; \
                (item)->next    = (list); \
                (list)->prev    = (item); \
                (list)          = (item); \
        } \
} while (0)

#define SWRAP_DLIST_REMOVE(list,item) do { \
        if ((list) == (item)) { \
                (list)          = (item)->next; \
                if (list) { \
                        (list)->prev    = NULL; \
                } \
        } else { \
                if ((item)->prev) { \
                        (item)->prev->next      = (item)->next; \
                } \
                if ((item)->next) { \
                        (item)->next->prev      = (item)->prev; \
                } \
        } \
        (item)->prev    = NULL; \
        (item)->next    = NULL; \
} while (0)

/* LD_PRELOAD doesn't work yet, so REWRITE_CALLS is all we support
 * for now */
#define REWRITE_CALLS

#ifdef REWRITE_CALLS
#define real_accept accept
#define real_connect connect
#define real_bind bind
#define real_listen listen
#define real_getpeername getpeername
#define real_getsockname getsockname
#define real_getsockopt getsockopt
#define real_setsockopt setsockopt
#define real_recvfrom recvfrom
#define real_sendto sendto
#define real_ioctl ioctl
#define real_recv recv
#define real_send send
#define real_socket socket
#define real_close close
#define real_dup dup
#define real_dup2 dup2
#endif

#ifdef HAVE_GETTIMEOFDAY_TZ
#define swrapGetTimeOfDay(tval) gettimeofday(tval,NULL)
#else
#define swrapGetTimeOfDay(tval) gettimeofday(tval)
#endif

/* we need to use a very terse format here as IRIX 6.4 silently
   truncates names to 16 chars, so if we use a longer name then we
   can't tell which port a packet came from with recvfrom()

   with this format we have 8 chars left for the directory name
*/
#define SOCKET_FORMAT "%c%02X%04X"
#define SOCKET_TYPE_CHAR_TCP            'T'
#define SOCKET_TYPE_CHAR_UDP            'U'
#define SOCKET_TYPE_CHAR_TCP_V6         'X'
#define SOCKET_TYPE_CHAR_UDP_V6         'Y'

#define MAX_WRAPPED_INTERFACES 16

#define SW_IPV6_ADDRESS 1

static struct sockaddr *sockaddr_dup(const void *data, socklen_t len)
{
        struct sockaddr *ret = (struct sockaddr *)malloc(len);
        memcpy(ret, data, len);
        return ret;
}

static void set_port(int family, int prt, struct sockaddr *addr)
{
        switch (family) {
        case AF_INET:
                ((struct sockaddr_in *)addr)->sin_port = htons(prt);
                break;
#ifdef HAVE_IPV6
        case AF_INET6:
                ((struct sockaddr_in6 *)addr)->sin6_port = htons(prt);
                break;
#endif
        }
}

static int socket_length(int family)
{
        switch (family) {
        case AF_INET:
                return sizeof(struct sockaddr_in);
#ifdef HAVE_IPV6
        case AF_INET6:
                return sizeof(struct sockaddr_in6);
#endif
        }
        return -1;
}



struct socket_info
{
        int fd;

        int family;
        int type;
        int protocol;
        int bound;
        int bcast;
        int is_server;

        char *path;
        char *tmp_path;

        struct sockaddr *myname;
        socklen_t myname_len;

        struct sockaddr *peername;
        socklen_t peername_len;

        struct {
                unsigned long pck_snd;
                unsigned long pck_rcv;
        } io;

        struct socket_info *prev, *next;
};

static struct socket_info *sockets;


static const char *socket_wrapper_dir(void)
{
        const char *s = getenv("SOCKET_WRAPPER_DIR");
        if (s == NULL) {
                return NULL;
        }
        if (strncmp(s, "./", 2) == 0) {
                s += 2;
        }
        return s;
}

static unsigned int socket_wrapper_default_iface(void)
{
        const char *s = getenv("SOCKET_WRAPPER_DEFAULT_IFACE");
        if (s) {
                unsigned int iface;
                if (sscanf(s, "%u", &iface) == 1) {
                        if (iface >= 1 && iface <= MAX_WRAPPED_INTERFACES) {
                                return iface;
                        }
                }
        }

        return 1;/* 127.0.0.1 */
}

static int convert_un_in(const struct sockaddr_un *un, struct sockaddr *in, socklen_t *len)
{
        unsigned int iface;
        unsigned int prt;
        const char *p;
        char type;

        p = strrchr(un->sun_path, '/');
        if (p) p++; else p = un->sun_path;

        if (sscanf(p, SOCKET_FORMAT, &type, &iface, &prt) != 3) {
                errno = EINVAL;
                return -1;
        }

        if (iface == 0 || iface > MAX_WRAPPED_INTERFACES) {
                errno = EINVAL;
                return -1;
        }

        if (prt > 0xFFFF) {
                errno = EINVAL;
                return -1;
        }

        switch(type) {
        case SOCKET_TYPE_CHAR_TCP:
        case SOCKET_TYPE_CHAR_UDP: {
                struct sockaddr_in *in2 = (struct sockaddr_in *)in;

                if ((*len) < sizeof(*in2)) {
                    errno = EINVAL;
                    return -1;
                }

                memset(in2, 0, sizeof(*in2));
                in2->sin_family = AF_INET;
                in2->sin_addr.s_addr = htonl((127<<24) | iface);
                in2->sin_port = htons(prt);

                *len = sizeof(*in2);
                break;
        }
#ifdef HAVE_IPV6
        case SOCKET_TYPE_CHAR_TCP_V6:
        case SOCKET_TYPE_CHAR_UDP_V6: {
                struct sockaddr_in6 *in2 = (struct sockaddr_in6 *)in;

                if ((*len) < sizeof(*in2)) {
                        errno = EINVAL;
                        return -1;
                }

                memset(in2, 0, sizeof(*in2));
                in2->sin6_family = AF_INET6;
                in2->sin6_addr.s6_addr[0] = SW_IPV6_ADDRESS;
                in2->sin6_port = htons(prt);

                *len = sizeof(*in2);
                break;
        }
#endif
        default:
                errno = EINVAL;
                return -1;
        }

        return 0;
}

static int convert_in_un_remote(struct socket_info *si, const struct sockaddr *inaddr, struct sockaddr_un *un,
                                int *bcast)
{
        char type = '\0';
        unsigned int prt;
        unsigned int iface;
        int is_bcast = 0;

        if (bcast) *bcast = 0;

        switch (si->family) {
        case AF_INET: {
                const struct sockaddr_in *in =
                    (const struct sockaddr_in *)inaddr;
                unsigned int addr = ntohl(in->sin_addr.s_addr);
                char u_type = '\0';
                char b_type = '\0';
                char a_type = '\0';

                switch (si->type) {
                case SOCK_STREAM:
                        u_type = SOCKET_TYPE_CHAR_TCP;
                        break;
                case SOCK_DGRAM:
                        u_type = SOCKET_TYPE_CHAR_UDP;
                        a_type = SOCKET_TYPE_CHAR_UDP;
                        b_type = SOCKET_TYPE_CHAR_UDP;
                        break;
                }

                prt = ntohs(in->sin_port);
                if (a_type && addr == 0xFFFFFFFF) {
                        /* 255.255.255.255 only udp */
                        is_bcast = 2;
                        type = a_type;
                        iface = socket_wrapper_default_iface();
                } else if (b_type && addr == 0x7FFFFFFF) {
                        /* 127.255.255.255 only udp */
                        is_bcast = 1;
                        type = b_type;
                        iface = socket_wrapper_default_iface();
                } else if ((addr & 0xFFFFFF00) == 0x7F000000) {
                        /* 127.0.0.X */
                        is_bcast = 0;
                        type = u_type;
                        iface = (addr & 0x000000FF);
                } else {
                        errno = ENETUNREACH;
                        return -1;
                }
                if (bcast) *bcast = is_bcast;
                break;
        }
#ifdef HAVE_IPV6
        case AF_INET6: {
                const struct sockaddr_in6 *in =
                    (const struct sockaddr_in6 *)inaddr;

                switch (si->type) {
                case SOCK_STREAM:
                        type = SOCKET_TYPE_CHAR_TCP_V6;
                        break;
                case SOCK_DGRAM:
                        type = SOCKET_TYPE_CHAR_UDP_V6;
                        break;
                }

                /* XXX no multicast/broadcast */

                prt = ntohs(in->sin6_port);
                iface = SW_IPV6_ADDRESS;

                break;
        }
#endif
        default:
                errno = ENETUNREACH;
                return -1;
        }

        if (prt == 0) {
                errno = EINVAL;
                return -1;
        }

        if (is_bcast) {
                snprintf(un->sun_path, sizeof(un->sun_path), "%s/EINVAL",
                         socket_wrapper_dir());
                /* the caller need to do more processing */
                return 0;
        }

        snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT,
                 socket_wrapper_dir(), type, iface, prt);

        return 0;
}

static int convert_in_un_alloc(struct socket_info *si, const struct sockaddr *inaddr, struct sockaddr_un *un,
                               int *bcast)
{
        char type = '\0';
        unsigned int prt;
        unsigned int iface;
        struct stat st;
        int is_bcast = 0;

        if (bcast) *bcast = 0;

        switch (si->family) {
        case AF_INET: {
                const struct sockaddr_in *in =
                    (const struct sockaddr_in *)inaddr;
                unsigned int addr = ntohl(in->sin_addr.s_addr);
                char u_type = '\0';
                char d_type = '\0';
                char b_type = '\0';
                char a_type = '\0';

                prt = ntohs(in->sin_port);

                switch (si->type) {
                case SOCK_STREAM:
                        u_type = SOCKET_TYPE_CHAR_TCP;
                        d_type = SOCKET_TYPE_CHAR_TCP;
                        break;
                case SOCK_DGRAM:
                        u_type = SOCKET_TYPE_CHAR_UDP;
                        d_type = SOCKET_TYPE_CHAR_UDP;
                        a_type = SOCKET_TYPE_CHAR_UDP;
                        b_type = SOCKET_TYPE_CHAR_UDP;
                        break;
                }

                if (addr == 0) {
                        /* 0.0.0.0 */
                        is_bcast = 0;
                        type = d_type;
                        iface = socket_wrapper_default_iface();
                } else if (a_type && addr == 0xFFFFFFFF) {
                        /* 255.255.255.255 only udp */
                        is_bcast = 2;
                        type = a_type;
                        iface = socket_wrapper_default_iface();
                } else if (b_type && addr == 0x7FFFFFFF) {
                        /* 127.255.255.255 only udp */
                        is_bcast = 1;
                        type = b_type;
                        iface = socket_wrapper_default_iface();
                } else if ((addr & 0xFFFFFF00) == 0x7F000000) {
                        /* 127.0.0.X */
                        is_bcast = 0;
                        type = u_type;
                        iface = (addr & 0x000000FF);
                } else {
                        errno = EADDRNOTAVAIL;
                        return -1;
                }
                break;
        }
#ifdef HAVE_IPV6
        case AF_INET6: {
                const struct sockaddr_in6 *in =
                    (const struct sockaddr_in6 *)inaddr;

                switch (si->type) {
                case SOCK_STREAM:
                        type = SOCKET_TYPE_CHAR_TCP_V6;
                        break;
                case SOCK_DGRAM:
                        type = SOCKET_TYPE_CHAR_UDP_V6;
                        break;
                }

                /* XXX no multicast/broadcast */

                prt = ntohs(in->sin6_port);
                iface = SW_IPV6_ADDRESS;

                break;
        }
#endif
        default:
                errno = ENETUNREACH;
                return -1;
        }


        if (bcast) *bcast = is_bcast;

        if (prt == 0) {
                /* handle auto-allocation of ephemeral ports */
                for (prt = 5001; prt < 10000; prt++) {
                        snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT,
                                 socket_wrapper_dir(), type, iface, prt);
                        if (stat(un->sun_path, &st) == 0) continue;

                        set_port(si->family, prt, si->myname);
                }
        }

        snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT,
                 socket_wrapper_dir(), type, iface, prt);
        return 0;
}

static struct socket_info *find_socket_info(int fd)
{
        struct socket_info *i;
        for (i = sockets; i; i = i->next) {
                if (i->fd == fd)
                        return i;
        }

        return NULL;
}

static int sockaddr_convert_to_un(struct socket_info *si, const struct sockaddr *in_addr, socklen_t in_len,
                                  struct sockaddr_un *out_addr, int alloc_sock, int *bcast)
{
        if (!out_addr)
                return 0;

        out_addr->sun_family = AF_UNIX;

        switch (in_addr->sa_family) {
        case AF_INET:
#ifdef HAVE_IPV6
        case AF_INET6:
#endif
                switch (si->type) {
                case SOCK_STREAM:
                case SOCK_DGRAM:
                        break;
                default:
                        errno = ESOCKTNOSUPPORT;
                        return -1;
                }
                if (alloc_sock) {
                        return convert_in_un_alloc(si, in_addr, out_addr, bcast);
                } else {
                        return convert_in_un_remote(si, in_addr, out_addr, bcast);
                }
        default:
                break;
        }

        errno = EAFNOSUPPORT;
        return -1;
}

static int sockaddr_convert_from_un(const struct socket_info *si,
                                    const struct sockaddr_un *in_addr,
                                    socklen_t un_addrlen,
                                    int family,
                                    struct sockaddr *out_addr,
                                    socklen_t *out_addrlen)
{
        if (out_addr == NULL || out_addrlen == NULL)
                return 0;

        if (un_addrlen == 0) {
                *out_addrlen = 0;
                return 0;
        }

        switch (family) {
        case AF_INET:
#ifdef HAVE_IPV6
        case AF_INET6:
#endif
                switch (si->type) {
                case SOCK_STREAM:
                case SOCK_DGRAM:
                        break;
                default:
                        errno = ESOCKTNOSUPPORT;
                        return -1;
                }
                return convert_un_in(in_addr, out_addr, out_addrlen);
        default:
                break;
        }

        errno = EAFNOSUPPORT;
        return -1;
}

enum swrap_packet_type {
        SWRAP_CONNECT_SEND,
        SWRAP_CONNECT_UNREACH,
        SWRAP_CONNECT_RECV,
        SWRAP_CONNECT_ACK,
        SWRAP_ACCEPT_SEND,
        SWRAP_ACCEPT_RECV,
        SWRAP_ACCEPT_ACK,
        SWRAP_RECVFROM,
        SWRAP_SENDTO,
        SWRAP_SENDTO_UNREACH,
        SWRAP_PENDING_RST,
        SWRAP_RECV,
        SWRAP_RECV_RST,
        SWRAP_SEND,
        SWRAP_SEND_RST,
        SWRAP_CLOSE_SEND,
        SWRAP_CLOSE_RECV,
        SWRAP_CLOSE_ACK
};

struct swrap_file_hdr {
        unsigned long   magic;
        unsigned short  version_major;
        unsigned short  version_minor;
        long            timezone;
        unsigned long   sigfigs;
        unsigned long   frame_max_len;
#define SWRAP_FRAME_LENGTH_MAX 0xFFFF
        unsigned long   link_type;
};
#define SWRAP_FILE_HDR_SIZE 24

struct swrap_packet {
        struct {
                unsigned long seconds;
                unsigned long micro_seconds;
                unsigned long recorded_length;
                unsigned long full_length;
        } frame;
#define SWRAP_PACKET__FRAME_SIZE 16

        struct {
                struct {
                        unsigned char   ver_hdrlen;
                        unsigned char   tos;
                        unsigned short  packet_length;
                        unsigned short  identification;
                        unsigned char   flags;
                        unsigned char   fragment;
                        unsigned char   ttl;
                        unsigned char   protocol;
                        unsigned short  hdr_checksum;
                        unsigned long   src_addr;
                        unsigned long   dest_addr;
                } hdr;
#define SWRAP_PACKET__IP_HDR_SIZE 20

                union {
                        struct {
                                unsigned short  source_port;
                                unsigned short  dest_port;
                                unsigned long   seq_num;
                                unsigned long   ack_num;
                                unsigned char   hdr_length;
                                unsigned char   control;
                                unsigned short  window;
                                unsigned short  checksum;
                                unsigned short  urg;
                        } tcp;
#define SWRAP_PACKET__IP_P_TCP_SIZE 20
                        struct {
                                unsigned short  source_port;
                                unsigned short  dest_port;
                                unsigned short  length;
                                unsigned short  checksum;
                        } udp;
#define SWRAP_PACKET__IP_P_UDP_SIZE 8
                        struct {
                                unsigned char   type;
                                unsigned char   code;
                                unsigned short  checksum;
                                unsigned long   unused;
                        } icmp;
#define SWRAP_PACKET__IP_P_ICMP_SIZE 8
                } p;
        } ip;
};
#define SWRAP_PACKET_SIZE 56

static const char *socket_wrapper_pcap_file(void)
{
        static int initialized = 0;
        static const char *s = NULL;
        static const struct swrap_file_hdr h;
        static const struct swrap_packet p;

        if (initialized == 1) {
                return s;
        }
        initialized = 1;

        /*
         * TODO: don't use the structs use plain buffer offsets
         *       and PUSH_U8(), PUSH_U16() and PUSH_U32()
         *
         * for now make sure we disable PCAP support
         * if the struct has alignment!
         */
        if (sizeof(h) != SWRAP_FILE_HDR_SIZE) {
                return NULL;
        }
        if (sizeof(p) != SWRAP_PACKET_SIZE) {
                return NULL;
        }
        if (sizeof(p.frame) != SWRAP_PACKET__FRAME_SIZE) {
                return NULL;
        }
        if (sizeof(p.ip.hdr) != SWRAP_PACKET__IP_HDR_SIZE) {
                return NULL;
        }
        if (sizeof(p.ip.p.tcp) != SWRAP_PACKET__IP_P_TCP_SIZE) {
                return NULL;
        }
        if (sizeof(p.ip.p.udp) != SWRAP_PACKET__IP_P_UDP_SIZE) {
                return NULL;
        }
        if (sizeof(p.ip.p.icmp) != SWRAP_PACKET__IP_P_ICMP_SIZE) {
                return NULL;
        }

        s = getenv("SOCKET_WRAPPER_PCAP_FILE");
        if (s == NULL) {
                return NULL;
        }
        if (strncmp(s, "./", 2) == 0) {
                s += 2;
        }
        return s;
}

static struct swrap_packet *swrap_packet_init(struct timeval *tval,
                                              const struct sockaddr_in *src_addr,
                                              const struct sockaddr_in *dest_addr,
                                              int socket_type,
                                              const unsigned char *payload,
                                              size_t payload_len,
                                              unsigned long tcp_seq,
                                              unsigned long tcp_ack,
                                              unsigned char tcp_ctl,
                                              int unreachable,
                                              size_t *_packet_len)
{
        struct swrap_packet *ret;
        struct swrap_packet *packet;
        size_t packet_len;
        size_t alloc_len;
        size_t nonwire_len = sizeof(packet->frame);
        size_t wire_hdr_len = 0;
        size_t wire_len = 0;
        size_t icmp_hdr_len = 0;
        size_t icmp_truncate_len = 0;
        unsigned char protocol = 0, icmp_protocol = 0;
        unsigned short src_port = src_addr->sin_port;
        unsigned short dest_port = dest_addr->sin_port;

        switch (socket_type) {
        case SOCK_STREAM:
                protocol = 0x06; /* TCP */
                wire_hdr_len = sizeof(packet->ip.hdr) + sizeof(packet->ip.p.tcp);
                wire_len = wire_hdr_len + payload_len;
                break;

        case SOCK_DGRAM:
                protocol = 0x11; /* UDP */
                wire_hdr_len = sizeof(packet->ip.hdr) + sizeof(packet->ip.p.udp);
                wire_len = wire_hdr_len + payload_len;
                break;
        }

        if (unreachable) {
                icmp_protocol = protocol;
                protocol = 0x01; /* ICMP */
                if (wire_len > 64 ) {
                        icmp_truncate_len = wire_len - 64;
                }
                icmp_hdr_len = sizeof(packet->ip.hdr) + sizeof(packet->ip.p.icmp);
                wire_hdr_len += icmp_hdr_len;
                wire_len += icmp_hdr_len;
        }

        packet_len = nonwire_len + wire_len;
        alloc_len = packet_len;
        if (alloc_len < sizeof(struct swrap_packet)) {
                alloc_len = sizeof(struct swrap_packet);
        }
        ret = (struct swrap_packet *)malloc(alloc_len);
        if (!ret) return NULL;

        packet = ret;

        packet->frame.seconds           = tval->tv_sec;
        packet->frame.micro_seconds     = tval->tv_usec;
        packet->frame.recorded_length   = wire_len - icmp_truncate_len;
        packet->frame.full_length       = wire_len - icmp_truncate_len;

        packet->ip.hdr.ver_hdrlen       = 0x45; /* version 4 and 5 * 32 bit words */
        packet->ip.hdr.tos              = 0x00;
        packet->ip.hdr.packet_length    = htons(wire_len - icmp_truncate_len);
        packet->ip.hdr.identification   = htons(0xFFFF);
        packet->ip.hdr.flags            = 0x40; /* BIT 1 set - means don't fraqment */
        packet->ip.hdr.fragment         = htons(0x0000);
        packet->ip.hdr.ttl              = 0xFF;
        packet->ip.hdr.protocol         = protocol;
        packet->ip.hdr.hdr_checksum     = htons(0x0000);
        packet->ip.hdr.src_addr         = src_addr->sin_addr.s_addr;
        packet->ip.hdr.dest_addr        = dest_addr->sin_addr.s_addr;

        if (unreachable) {
                packet->ip.p.icmp.type          = 0x03; /* destination unreachable */
                packet->ip.p.icmp.code          = 0x01; /* host unreachable */
                packet->ip.p.icmp.checksum      = htons(0x0000);
                packet->ip.p.icmp.unused        = htonl(0x00000000);

                /* set the ip header in the ICMP payload */
                packet = (struct swrap_packet *)(((unsigned char *)ret) + icmp_hdr_len);
                packet->ip.hdr.ver_hdrlen       = 0x45; /* version 4 and 5 * 32 bit words */
                packet->ip.hdr.tos              = 0x00;
                packet->ip.hdr.packet_length    = htons(wire_len - icmp_hdr_len);
                packet->ip.hdr.identification   = htons(0xFFFF);
                packet->ip.hdr.flags            = 0x40; /* BIT 1 set - means don't fraqment */
                packet->ip.hdr.fragment         = htons(0x0000);
                packet->ip.hdr.ttl              = 0xFF;
                packet->ip.hdr.protocol         = icmp_protocol;
                packet->ip.hdr.hdr_checksum     = htons(0x0000);
                packet->ip.hdr.src_addr         = dest_addr->sin_addr.s_addr;
                packet->ip.hdr.dest_addr        = src_addr->sin_addr.s_addr;

                src_port = dest_addr->sin_port;
                dest_port = src_addr->sin_port;
        }

        switch (socket_type) {
        case SOCK_STREAM:
                packet->ip.p.tcp.source_port    = src_port;
                packet->ip.p.tcp.dest_port      = dest_port;
                packet->ip.p.tcp.seq_num        = htonl(tcp_seq);
                packet->ip.p.tcp.ack_num        = htonl(tcp_ack);
                packet->ip.p.tcp.hdr_length     = 0x50; /* 5 * 32 bit words */
                packet->ip.p.tcp.control        = tcp_ctl;
                packet->ip.p.tcp.window         = htons(0x7FFF);
                packet->ip.p.tcp.checksum       = htons(0x0000);
                packet->ip.p.tcp.urg            = htons(0x0000);

                break;

        case SOCK_DGRAM:
                packet->ip.p.udp.source_port    = src_addr->sin_port;
                packet->ip.p.udp.dest_port      = dest_addr->sin_port;
                packet->ip.p.udp.length         = htons(8 + payload_len);
                packet->ip.p.udp.checksum       = htons(0x0000);

                break;
        }

        if (payload && payload_len > 0) {
                unsigned char *p = (unsigned char *)ret;
                p += nonwire_len;
                p += wire_hdr_len;
                memcpy(p, payload, payload_len);
        }

        *_packet_len = packet_len - icmp_truncate_len;
        return ret;
}

static int swrap_get_pcap_fd(const char *fname)
{
        static int fd = -1;

        if (fd != -1) return fd;

        fd = open(fname, O_WRONLY|O_CREAT|O_EXCL|O_APPEND, 0644);
        if (fd != -1) {
                struct swrap_file_hdr file_hdr;
                file_hdr.magic          = 0xA1B2C3D4;
                file_hdr.version_major  = 0x0002;
                file_hdr.version_minor  = 0x0004;
                file_hdr.timezone       = 0x00000000;
                file_hdr.sigfigs        = 0x00000000;
                file_hdr.frame_max_len  = SWRAP_FRAME_LENGTH_MAX;
                file_hdr.link_type      = 0x0065; /* 101 RAW IP */

                write(fd, &file_hdr, sizeof(file_hdr));
                return fd;
        }

        fd = open(fname, O_WRONLY|O_APPEND, 0644);

        return fd;
}

static void swrap_dump_packet(struct socket_info *si, const struct sockaddr *addr,
                              enum swrap_packet_type type,
                              const void *buf, size_t len)
{
        const struct sockaddr_in *src_addr;
        const struct sockaddr_in *dest_addr;
        const char *file_name;
        unsigned long tcp_seq = 0;
        unsigned long tcp_ack = 0;
        unsigned char tcp_ctl = 0;
        int unreachable = 0;
        struct timeval tv;
        struct swrap_packet *packet;
        size_t packet_len = 0;
        int fd;

        file_name = socket_wrapper_pcap_file();
        if (!file_name) {
                return;
        }

        switch (si->family) {
        case AF_INET:
#ifdef HAVE_IPV6
        case AF_INET6:
#endif
                break;
        default:
                return;
        }

        switch (type) {
        case SWRAP_CONNECT_SEND:
                if (si->type != SOCK_STREAM) return;

                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)addr;

                tcp_seq = si->io.pck_snd;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x02; /* SYN */

                si->io.pck_snd += 1;

                break;

        case SWRAP_CONNECT_RECV:
                if (si->type != SOCK_STREAM) return;

                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)addr;

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x12; /** SYN,ACK */

                si->io.pck_rcv += 1;

                break;

        case SWRAP_CONNECT_UNREACH:
                if (si->type != SOCK_STREAM) return;

                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)addr;

                /* Unreachable: resend the data of SWRAP_CONNECT_SEND */
                tcp_seq = si->io.pck_snd - 1;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x02; /* SYN */
                unreachable = 1;

                break;

        case SWRAP_CONNECT_ACK:
                if (si->type != SOCK_STREAM) return;

                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)addr;

                tcp_seq = si->io.pck_snd;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x10; /* ACK */

                break;

        case SWRAP_ACCEPT_SEND:
                if (si->type != SOCK_STREAM) return;

                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)addr;

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x02; /* SYN */

                si->io.pck_rcv += 1;

                break;

        case SWRAP_ACCEPT_RECV:
                if (si->type != SOCK_STREAM) return;

                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)addr;

                tcp_seq = si->io.pck_snd;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x12; /* SYN,ACK */

                si->io.pck_snd += 1;

                break;

        case SWRAP_ACCEPT_ACK:
                if (si->type != SOCK_STREAM) return;

                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)addr;

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x10; /* ACK */

                break;

        case SWRAP_SEND:
                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)si->peername;

                tcp_seq = si->io.pck_snd;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x18; /* PSH,ACK */

                si->io.pck_snd += len;

                break;

        case SWRAP_SEND_RST:
                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)si->peername;

                if (si->type == SOCK_DGRAM) {
                        swrap_dump_packet(si, si->peername,
                                          SWRAP_SENDTO_UNREACH,
                                          buf, len);
                        return;
                }

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x14; /** RST,ACK */

                break;

        case SWRAP_PENDING_RST:
                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)si->peername;

                if (si->type == SOCK_DGRAM) {
                        return;
                }

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x14; /* RST,ACK */

                break;

        case SWRAP_RECV:
                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)si->peername;

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x18; /* PSH,ACK */

                si->io.pck_rcv += len;

                break;

        case SWRAP_RECV_RST:
                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)si->peername;

                if (si->type == SOCK_DGRAM) {
                        return;
                }

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x14; /* RST,ACK */

                break;

        case SWRAP_SENDTO:
                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)addr;

                si->io.pck_snd += len;

                break;

        case SWRAP_SENDTO_UNREACH:
                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)addr;

                unreachable = 1;

                break;

        case SWRAP_RECVFROM:
                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)addr;

                si->io.pck_rcv += len;

                break;

        case SWRAP_CLOSE_SEND:
                if (si->type != SOCK_STREAM) return;

                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)si->peername;

                tcp_seq = si->io.pck_snd;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x11; /* FIN, ACK */

                si->io.pck_snd += 1;

                break;

        case SWRAP_CLOSE_RECV:
                if (si->type != SOCK_STREAM) return;

                dest_addr = (const struct sockaddr_in *)si->myname;
                src_addr = (const struct sockaddr_in *)si->peername;

                tcp_seq = si->io.pck_rcv;
                tcp_ack = si->io.pck_snd;
                tcp_ctl = 0x11; /* FIN,ACK */

                si->io.pck_rcv += 1;

                break;

        case SWRAP_CLOSE_ACK:
                if (si->type != SOCK_STREAM) return;

                src_addr = (const struct sockaddr_in *)si->myname;
                dest_addr = (const struct sockaddr_in *)si->peername;

                tcp_seq = si->io.pck_snd;
                tcp_ack = si->io.pck_rcv;
                tcp_ctl = 0x10; /* ACK */

                break;
        default:
                return;
        }

        swrapGetTimeOfDay(&tv);

        packet = swrap_packet_init(&tv, src_addr, dest_addr, si->type,
                                   (const unsigned char *)buf, len,
                                   tcp_seq, tcp_ack, tcp_ctl, unreachable,
                                   &packet_len);
        if (!packet) {
                return;
        }

        fd = swrap_get_pcap_fd(file_name);
        if (fd != -1) {
                write(fd, packet, packet_len);
        }

        free(packet);
}

_PUBLIC_ int swrap_socket(int family, int type, int protocol)
{
        struct socket_info *si;
        int fd;

        if (!socket_wrapper_dir()) {
                return real_socket(family, type, protocol);
        }

        switch (family) {
        case AF_INET:
#ifdef HAVE_IPV6
        case AF_INET6:
#endif
                break;
        case AF_UNIX:
                return real_socket(family, type, protocol);
        default:
                errno = EAFNOSUPPORT;
                return -1;
        }

        switch (type) {
        case SOCK_STREAM:
                break;
        case SOCK_DGRAM:
                break;
        default:
                errno = EPROTONOSUPPORT;
                return -1;
        }

#if 0
        switch (protocol) {
        case 0:
                break;
        default:
                errno = EPROTONOSUPPORT;
                return -1;
        }
#endif

        fd = real_socket(AF_UNIX, type, 0);

        if (fd == -1) return -1;

        si = (struct socket_info *)calloc(1, sizeof(struct socket_info));

        si->family = family;
        si->type = type;
        si->protocol = protocol;
        si->fd = fd;

        SWRAP_DLIST_ADD(sockets, si);

        return si->fd;
}

_PUBLIC_ int swrap_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
{
        struct socket_info *parent_si, *child_si;
        int fd;
        struct sockaddr_un un_addr;
        socklen_t un_addrlen = sizeof(un_addr);
        struct sockaddr_un un_my_addr;
        socklen_t un_my_addrlen = sizeof(un_my_addr);
        struct sockaddr *my_addr;
        socklen_t my_addrlen, len;
        int ret;

        parent_si = find_socket_info(s);
        if (!parent_si) {
                return real_accept(s, addr, addrlen);
        }

        /*
         * assume out sockaddr have the same size as the in parent
         * socket family
         */
        my_addrlen = socket_length(parent_si->family);
        if (my_addrlen < 0) {
                errno = EINVAL;
                return -1;
        }

        my_addr = malloc(my_addrlen);
        if (my_addr == NULL) {
                return -1;
        }

        memset(&un_addr, 0, sizeof(un_addr));
        memset(&un_my_addr, 0, sizeof(un_my_addr));

        ret = real_accept(s, (struct sockaddr *)&un_addr, &un_addrlen);
        if (ret == -1) {
                free(my_addr);
                return ret;
        }

        fd = ret;

        len = my_addrlen;
        ret = sockaddr_convert_from_un(parent_si, &un_addr, un_addrlen,
                                       parent_si->family, my_addr, &len);
        if (ret == -1) {
                free(my_addr);
                close(fd);
                return ret;
        }

        child_si = (struct socket_info *)malloc(sizeof(struct socket_info));
        memset(child_si, 0, sizeof(*child_si));

        child_si->fd = fd;
        child_si->family = parent_si->family;
        child_si->type = parent_si->type;
        child_si->protocol = parent_si->protocol;
        child_si->bound = 1;
        child_si->is_server = 1;

        child_si->peername_len = len;
        child_si->peername = sockaddr_dup(my_addr, len);

        if (addr != NULL && addrlen != NULL) {
            *addrlen = len;
            if (*addrlen >= len)
                memcpy(addr, my_addr, len);
            *addrlen = 0;
        }

        ret = real_getsockname(fd, (struct sockaddr *)&un_my_addr, &un_my_addrlen);
        if (ret == -1) {
                free(child_si);
                close(fd);
                return ret;
        }

        len = my_addrlen;
        ret = sockaddr_convert_from_un(child_si, &un_my_addr, un_my_addrlen,
                                       child_si->family, my_addr, &len);
        if (ret == -1) {
                free(child_si);
                free(my_addr);
                close(fd);
                return ret;
        }

        child_si->myname_len = len;
        child_si->myname = sockaddr_dup(my_addr, len);
        free(my_addr);

        SWRAP_DLIST_ADD(sockets, child_si);

        swrap_dump_packet(child_si, addr, SWRAP_ACCEPT_SEND, NULL, 0);
        swrap_dump_packet(child_si, addr, SWRAP_ACCEPT_RECV, NULL, 0);
        swrap_dump_packet(child_si, addr, SWRAP_ACCEPT_ACK, NULL, 0);

        return fd;
}

static int autobind_start_init;
static int autobind_start;

/* using sendto() or connect() on an unbound socket would give the
   recipient no way to reply, as unlike UDP and TCP, a unix domain
   socket can't auto-assign emphemeral port numbers, so we need to
   assign it here */
static int swrap_auto_bind(struct socket_info *si)
{
        struct sockaddr_un un_addr;
        int i;
        char type;
        int ret;
        int port;
        struct stat st;

        if (autobind_start_init != 1) {
                autobind_start_init = 1;
                autobind_start = getpid();
                autobind_start %= 50000;
                autobind_start += 10000;
        }

        un_addr.sun_family = AF_UNIX;

        switch (si->family) {
        case AF_INET: {
                struct sockaddr_in in;

                switch (si->type) {
                case SOCK_STREAM:
                        type = SOCKET_TYPE_CHAR_TCP;
                        break;
                case SOCK_DGRAM:
                        type = SOCKET_TYPE_CHAR_UDP;
                        break;
                default:
                    errno = ESOCKTNOSUPPORT;
                    return -1;
                }

                memset(&in, 0, sizeof(in));
                in.sin_family = AF_INET;
                in.sin_addr.s_addr = htonl(127<<24 |
                                           socket_wrapper_default_iface());

                si->myname_len = sizeof(in);
                si->myname = sockaddr_dup(&in, si->myname_len);
                break;
        }
#ifdef HAVE_IPV6
        case AF_INET6: {
                struct sockaddr_in6 in6;

                switch (si->type) {
                case SOCK_STREAM:
                        type = SOCKET_TYPE_CHAR_TCP_V6;
                        break;
                case SOCK_DGRAM:
                        type = SOCKET_TYPE_CHAR_UDP_V6;
                        break;
                default:
                    errno = ESOCKTNOSUPPORT;
                    return -1;
                }

                memset(&in6, 0, sizeof(in6));
                in6.sin6_family = AF_INET6;
                in6.sin6_addr.s6_addr[0] = SW_IPV6_ADDRESS;
                si->myname_len = sizeof(in6);
                si->myname = sockaddr_dup(&in6, si->myname_len);
                break;
        }
#endif
        default:
                errno = ESOCKTNOSUPPORT;
                return -1;
        }

        if (autobind_start > 60000) {
                autobind_start = 10000;
        }

        for (i=0;i<1000;i++) {
                port = autobind_start + i;
                snprintf(un_addr.sun_path, sizeof(un_addr.sun_path),
                         "%s/"SOCKET_FORMAT, socket_wrapper_dir(),
                         type, socket_wrapper_default_iface(), port);
                if (stat(un_addr.sun_path, &st) == 0) continue;

                ret = real_bind(si->fd, (struct sockaddr *)&un_addr, sizeof(un_addr));
                if (ret == -1) return ret;

                si->tmp_path = strdup(un_addr.sun_path);
                si->bound = 1;
                autobind_start = port + 1;
                break;
        }
        if (i == 1000) {
                errno = ENFILE;
                return -1;
        }

        set_port(si->family, port, si->myname);

        return 0;
}


_PUBLIC_ int swrap_connect(int s, const struct sockaddr *serv_addr, socklen_t addrlen)
{
        int ret;
        struct sockaddr_un un_addr;
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_connect(s, serv_addr, addrlen);
        }

        if (si->bound == 0) {
                ret = swrap_auto_bind(si);
                if (ret == -1) return -1;
        }

        if (si->family != serv_addr->sa_family) {
                errno = EINVAL;
                return -1;
        }

        ret = sockaddr_convert_to_un(si, (const struct sockaddr *)serv_addr, addrlen, &un_addr, 0, NULL);
        if (ret == -1) return -1;

        swrap_dump_packet(si, serv_addr, SWRAP_CONNECT_SEND, NULL, 0);

        ret = real_connect(s, (struct sockaddr *)&un_addr,
                           sizeof(struct sockaddr_un));

        /* to give better errors */
        if (ret == -1 && errno == ENOENT) {
                errno = EHOSTUNREACH;
        }

        if (ret == 0) {
                si->peername_len = addrlen;
                si->peername = sockaddr_dup(serv_addr, addrlen);

                swrap_dump_packet(si, serv_addr, SWRAP_CONNECT_RECV, NULL, 0);
                swrap_dump_packet(si, serv_addr, SWRAP_CONNECT_ACK, NULL, 0);
        } else {
                swrap_dump_packet(si, serv_addr, SWRAP_CONNECT_UNREACH, NULL, 0);
        }

        return ret;
}

_PUBLIC_ int swrap_bind(int s, const struct sockaddr *myaddr, socklen_t addrlen)
{
        int ret;
        struct sockaddr_un un_addr;
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_bind(s, myaddr, addrlen);
        }

        si->myname_len = addrlen;
        si->myname = sockaddr_dup(myaddr, addrlen);

        ret = sockaddr_convert_to_un(si, (const struct sockaddr *)myaddr, addrlen, &un_addr, 1, &si->bcast);
        if (ret == -1) return -1;

        unlink(un_addr.sun_path);

        ret = real_bind(s, (struct sockaddr *)&un_addr,
                        sizeof(struct sockaddr_un));

        if (ret == 0) {
                si->bound = 1;
        }

        return ret;
}

_PUBLIC_ int swrap_listen(int s, int backlog)
{
        int ret;
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_listen(s, backlog);
        }

        ret = real_listen(s, backlog);

        return ret;
}

_PUBLIC_ int swrap_getpeername(int s, struct sockaddr *name, socklen_t *addrlen)
{
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_getpeername(s, name, addrlen);
        }

        if (!si->peername)
        {
                errno = ENOTCONN;
                return -1;
        }

        memcpy(name, si->peername, si->peername_len);
        *addrlen = si->peername_len;

        return 0;
}

_PUBLIC_ int swrap_getsockname(int s, struct sockaddr *name, socklen_t *addrlen)
{
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_getsockname(s, name, addrlen);
        }

        memcpy(name, si->myname, si->myname_len);
        *addrlen = si->myname_len;

        return 0;
}

_PUBLIC_ int swrap_getsockopt(int s, int level, int optname, void *optval, socklen_t *optlen)
{
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_getsockopt(s, level, optname, optval, optlen);
        }

        if (level == SOL_SOCKET) {
                return real_getsockopt(s, level, optname, optval, optlen);
        }

        errno = ENOPROTOOPT;
        return -1;
}

_PUBLIC_ int swrap_setsockopt(int s, int  level,  int  optname,  const  void  *optval, socklen_t optlen)
{
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_setsockopt(s, level, optname, optval, optlen);
        }

        if (level == SOL_SOCKET) {
                return real_setsockopt(s, level, optname, optval, optlen);
        }

        switch (si->family) {
        case AF_INET:
                return 0;
        default:
                errno = ENOPROTOOPT;
                return -1;
        }
}

_PUBLIC_ ssize_t swrap_recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen)
{
        struct sockaddr_un un_addr;
        socklen_t un_addrlen = sizeof(un_addr);
        int ret;
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_recvfrom(s, buf, len, flags, from, fromlen);
        }

        /* irix 6.4 forgets to null terminate the sun_path string :-( */
        memset(&un_addr, 0, sizeof(un_addr));
        ret = real_recvfrom(s, buf, len, flags, (struct sockaddr *)&un_addr, &un_addrlen);
        if (ret == -1)
                return ret;

        if (sockaddr_convert_from_un(si, &un_addr, un_addrlen,
                                     si->family, from, fromlen) == -1) {
                return -1;
        }

        swrap_dump_packet(si, from, SWRAP_RECVFROM, buf, ret);

        return ret;
}


_PUBLIC_ ssize_t swrap_sendto(int s, const void *buf, size_t len, int flags, const struct sockaddr *to, socklen_t tolen)
{
        struct sockaddr_un un_addr;
        int ret;
        struct socket_info *si = find_socket_info(s);
        int bcast = 0;

        if (!si) {
                return real_sendto(s, buf, len, flags, to, tolen);
        }

        switch (si->type) {
        case SOCK_STREAM:
                ret = real_send(s, buf, len, flags);
                break;
        case SOCK_DGRAM:
                if (si->bound == 0) {
                        ret = swrap_auto_bind(si);
                        if (ret == -1) return -1;
                }

                ret = sockaddr_convert_to_un(si, to, tolen, &un_addr, 0, &bcast);
                if (ret == -1) return -1;

                if (bcast) {
                        struct stat st;
                        unsigned int iface;
                        unsigned int prt = ntohs(((const struct sockaddr_in *)to)->sin_port);
                        char type;

                        type = SOCKET_TYPE_CHAR_UDP;

                        for(iface=0; iface <= MAX_WRAPPED_INTERFACES; iface++) {
                                snprintf(un_addr.sun_path, sizeof(un_addr.sun_path), "%s/"SOCKET_FORMAT,
                                         socket_wrapper_dir(), type, iface, prt);
                                if (stat(un_addr.sun_path, &st) != 0) continue;

                                /* ignore the any errors in broadcast sends */
                                real_sendto(s, buf, len, flags, (struct sockaddr *)&un_addr, sizeof(un_addr));
                        }

                        swrap_dump_packet(si, to, SWRAP_SENDTO, buf, len);

                        return len;
                }

                ret = real_sendto(s, buf, len, flags, (struct sockaddr *)&un_addr, sizeof(un_addr));
                break;
        default:
                ret = -1;
                errno = EHOSTUNREACH;
                break;
        }

        /* to give better errors */
        if (ret == -1 && errno == ENOENT) {
                errno = EHOSTUNREACH;
        }

        if (ret == -1) {
                swrap_dump_packet(si, to, SWRAP_SENDTO, buf, len);
                swrap_dump_packet(si, to, SWRAP_SENDTO_UNREACH, buf, len);
        } else {
                swrap_dump_packet(si, to, SWRAP_SENDTO, buf, ret);
        }

        return ret;
}

_PUBLIC_ int swrap_ioctl(int s, int r, void *p)
{
        int ret;
        struct socket_info *si = find_socket_info(s);
        int value;

        if (!si) {
                return real_ioctl(s, r, p);
        }

        ret = real_ioctl(s, r, p);

        switch (r) {
        case FIONREAD:
                value = *((int *)p);
                if (ret == -1 && errno != EAGAIN && errno != ENOBUFS) {
                        swrap_dump_packet(si, NULL, SWRAP_PENDING_RST, NULL, 0);
                } else if (value == 0) { /* END OF FILE */
                        swrap_dump_packet(si, NULL, SWRAP_PENDING_RST, NULL, 0);
                }
                break;
        }

        return ret;
}

_PUBLIC_ ssize_t swrap_recv(int s, void *buf, size_t len, int flags)
{
        int ret;
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_recv(s, buf, len, flags);
        }

        ret = real_recv(s, buf, len, flags);
        if (ret == -1 && errno != EAGAIN && errno != ENOBUFS) {
                swrap_dump_packet(si, NULL, SWRAP_RECV_RST, NULL, 0);
        } else if (ret == 0) { /* END OF FILE */
                swrap_dump_packet(si, NULL, SWRAP_RECV_RST, NULL, 0);
        } else {
                swrap_dump_packet(si, NULL, SWRAP_RECV, buf, ret);
        }

        return ret;
}


_PUBLIC_ ssize_t swrap_send(int s, const void *buf, size_t len, int flags)
{
        int ret;
        struct socket_info *si = find_socket_info(s);

        if (!si) {
                return real_send(s, buf, len, flags);
        }

        ret = real_send(s, buf, len, flags);

        if (ret == -1) {
                swrap_dump_packet(si, NULL, SWRAP_SEND, buf, len);
                swrap_dump_packet(si, NULL, SWRAP_SEND_RST, NULL, 0);
        } else {
                swrap_dump_packet(si, NULL, SWRAP_SEND, buf, ret);
        }

        return ret;
}

_PUBLIC_ int swrap_close(int fd)
{
        struct socket_info *si = find_socket_info(fd);
        int ret;

        if (!si) {
                return real_close(fd);
        }

        SWRAP_DLIST_REMOVE(sockets, si);

        if (si->myname && si->peername) {
                swrap_dump_packet(si, NULL, SWRAP_CLOSE_SEND, NULL, 0);
        }

        ret = real_close(fd);

        if (si->myname && si->peername) {
                swrap_dump_packet(si, NULL, SWRAP_CLOSE_RECV, NULL, 0);
                swrap_dump_packet(si, NULL, SWRAP_CLOSE_ACK, NULL, 0);
        }

        if (si->path) free(si->path);
        if (si->myname) free(si->myname);
        if (si->peername) free(si->peername);
        if (si->tmp_path) {
                unlink(si->tmp_path);
                free(si->tmp_path);
        }
        free(si);

        return ret;
}

static int
dup_internal(const struct socket_info *si_oldd, int fd)
{
        struct socket_info *si_newd;

        si_newd = (struct socket_info *)calloc(1, sizeof(struct socket_info));

        si_newd->fd = fd;

        si_newd->family = si_oldd->family;
        si_newd->type = si_oldd->type;
        si_newd->protocol = si_oldd->protocol;
        si_newd->bound = si_oldd->bound;
        si_newd->bcast = si_oldd->bcast;
        if (si_oldd->path)
                si_newd->path = strdup(si_oldd->path);
        if (si_oldd->tmp_path)
                si_newd->tmp_path = strdup(si_oldd->tmp_path);
        si_newd->myname =
            sockaddr_dup(si_oldd->myname, si_oldd->myname_len);
        si_newd->myname_len = si_oldd->myname_len;
        si_newd->peername =
            sockaddr_dup(si_oldd->peername, si_oldd->peername_len);
        si_newd->peername_len = si_oldd->peername_len;

        si_newd->io = si_oldd->io;

        SWRAP_DLIST_ADD(sockets, si_newd);

        return fd;
}


_PUBLIC_ int swrap_dup(int oldd)
{
        struct socket_info *si;
        int fd;

        si = find_socket_info(oldd);
        if (si == NULL)
                return real_dup(oldd);

        fd = real_dup(si->fd);
        if (fd < 0)
                return fd;

        return dup_internal(si, fd);
}


_PUBLIC_ int swrap_dup2(int oldd, int newd)
{
        struct socket_info *si_newd, *si_oldd;
        int fd;

        if (newd == oldd)
            return newd;

        si_oldd = find_socket_info(oldd);
        si_newd = find_socket_info(newd);

        if (si_oldd == NULL && si_newd == NULL)
                return real_dup2(oldd, newd);

        fd = real_dup2(si_oldd->fd, newd);
        if (fd < 0)
                return fd;

        /* close new socket first */
        if (si_newd)
                swrap_close(newd);

        return dup_internal(si_oldd, fd);
}