/*
 *  Copyright (c) 2002 Erik Fears
 *  Copyright (c) 2014-2019 ircd-hybrid development team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 *  USA
 */

#include "setup.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>

#include "compat.h"
#include "config.h"
#include "irc.h"
#include "log.h"
#include "stats.h"
#include "dnsbl.h"
#include "options.h"
#include "negcache.h"
#include "main.h"
#include "memory.h"
#include "match.h"
#include "misc.h"
#include "scan.h"

/* libopm includes */
#include "libopm/src/opm.h"
#include "libopm/src/opm_common.h"
#include "libopm/src/opm_error.h"
#include "libopm/src/opm_types.h"


/* GLOBAL LIST */
static list_t SCANNERS;  /* List of OPM_T */

/* Function declarations */
static struct scan_struct *scan_create(const char *[], const char *);
static void scan_free(struct scan_struct *);
static void scan_irckline(const struct scan_struct *, const char *, const char *);
static void scan_negative(const struct scan_struct *);
static void scan_log(OPM_REMOTE_T *);

/** Callbacks for LIBOPM */
static void scan_open_proxy(OPM_T *, OPM_REMOTE_T *, int, void *);
static void scan_negotiation_failed(OPM_T *, OPM_REMOTE_T *, int, void *);
static void scan_timeout(OPM_T *, OPM_REMOTE_T *, int, void *);
static void scan_end(OPM_T *, OPM_REMOTE_T *, int, void *);
static void scan_handle_error(OPM_T *, OPM_REMOTE_T *, int, void *);

extern FILE *scanlogfile;


/* scan_cycle
 *
 *    Perform scanner tasks.
 */
void
scan_cycle(void)
{
  node_t *node;

  /* Cycle through the blacklist first.. */
  dnsbl_cycle();

  /* Cycle each scanner object */
  LIST_FOREACH(node, SCANNERS.head)
  {
    struct scanner_struct *scs = node->data;
    opm_cycle(scs->scanner);
  }
}

/* scan_timer
 *
 *    Perform actions that are to be performed every ~1 second.
 *
 * Parameters: NONE
 * Return: NONE
 *
 */
void
scan_timer(void)
{
  static time_t nc_counter;

  if (OptionsItem.negcache)
  {
    if (nc_counter++ >= OptionsItem.negcache_rebuild)
    {
      /*
       * Time to rebuild the negative cache.
       */
      if (OPT_DEBUG)
        log_printf("SCAN -> Rebuilding negative cache");

      negcache_rebuild();
      nc_counter = 0;
    }
  }
}

/* scan_gettype(int protocol)
 *
 *    Return human readable name of OPM PROTOCOL given OPM_TYPE_PROTOCOL
 *
 * Parameters:
 *    protocol: Protocol to return (from libopm/src/opm_types.h)
 *
 * Return:
 *    Pointer to static string containing human readable form of protocol
 *    name
 *
 */
const char *
scan_gettype(int protocol)
{
  static const char *const undef = "undefined";
  static const struct protocol_assoc protocols[] =
  {
    { .type = OPM_TYPE_HTTP,      .name = "HTTP"      },
    { .type = OPM_TYPE_HTTPPOST,  .name = "HTTPPOST"  },
    { .type = OPM_TYPE_SOCKS4,    .name = "SOCKS4"    },
    { .type = OPM_TYPE_SOCKS5,    .name = "SOCKS5"    },
    { .type = OPM_TYPE_WINGATE,   .name = "WINGATE"   },
    { .type = OPM_TYPE_ROUTER,    .name = "ROUTER"    },
    { .type = OPM_TYPE_HTTPS,     .name = "HTTPS"     },
    { .type = OPM_TYPE_HTTPSPOST, .name = "HTTPSPOST" },
    { .type = OPM_TYPE_DREAMBOX,  .name = "DREAMBOX"  },
    { .type = OPM_TYPE_SSH,       .name = "SSH"       },
    { .type = 0 }
  };

  for (const struct protocol_assoc *tab = protocols; tab->type; ++tab)
    if (protocol == tab->type)
      return tab->name;

  return undef;
}

/* scan_checkexempt
 *
 *    Check mask against exempt list.
 *
 * Parameters:
 *     mask: Mask to check
 *
 * Return:
 *     1 if mask is in list
 *     0 if mask is not in list
 */
static int
scan_checkexempt(const char *mask, const char *ipmask)
{
  node_t *node;

  LIST_FOREACH(node, ExemptItem.masks.head)
  {
    const char *exempt_mask = node->data;

    if (match(exempt_mask, mask) == 0 || match(exempt_mask, ipmask) == 0)
      return 1;
  }

  return 0;
}

/* scan_init

      Initialize scanner and masks list based on configuration.

   Parameters:
      None

   Return:
      None
*/
void
scan_init(void)
{
  node_t *p, *p2, *p3, *p4;

  /* Setup each individual scanner */
  LIST_FOREACH(p, ScannerItemList.head)
  {
    struct ScannerConf *sc = p->data;

    if (OPT_DEBUG)
      log_printf("SCAN -> Setting up scanner [%s]", sc->name);

    /* Build the scanner */
    struct scanner_struct *scs = xcalloc(sizeof(*scs));
    scs->scanner = opm_create();
    scs->name = xstrdup(sc->name);

    /* Setup configuration */
    opm_config(scs->scanner, OPM_CONFIG_FD_LIMIT, &sc->fd);
    opm_config(scs->scanner, OPM_CONFIG_SCAN_IP, sc->target_ip);
    opm_config(scs->scanner, OPM_CONFIG_SCAN_PORT, &sc->target_port);
    opm_config(scs->scanner, OPM_CONFIG_TIMEOUT, &sc->timeout);
    opm_config(scs->scanner, OPM_CONFIG_MAX_READ, &sc->max_read);
    opm_config(scs->scanner, OPM_CONFIG_BIND_IP, sc->vhost);

    /* add target strings */
    LIST_FOREACH(p2, sc->target_string.head)
      opm_config(scs->scanner, OPM_CONFIG_TARGET_STRING, p2->data);

    /* Setup callbacks */
    opm_callback(scs->scanner, OPM_CALLBACK_OPENPROXY, &scan_open_proxy, scs);
    opm_callback(scs->scanner, OPM_CALLBACK_NEGFAIL, &scan_negotiation_failed, scs);
    opm_callback(scs->scanner, OPM_CALLBACK_TIMEOUT, &scan_timeout, scs);
    opm_callback(scs->scanner, OPM_CALLBACK_END, &scan_end, scs);
    opm_callback(scs->scanner, OPM_CALLBACK_ERROR, &scan_handle_error, scs);

    /* Setup the protocols */
    LIST_FOREACH(p2, sc->protocols.head)
    {
      struct ProtocolConf *pc = p2->data;

      if (OPT_DEBUG >= 2)
        log_printf("SCAN -> Adding protocol %s:%d to scanner [%s]",
                   scan_gettype(pc->type), pc->port, scs->name);

      if (opm_addtype(scs->scanner, pc->type, pc->port) == OPM_ERR_BADPROTOCOL)
        log_printf("SCAN -> Error bad protocol %s:%d in scanner [%s]",
                    scan_gettype(pc->type), pc->port, scs->name);
    }

    list_add(scs, node_create(), &SCANNERS);
  }

  /* Give scanners a list of masks they scan */
  LIST_FOREACH(p, SCANNERS.head)
  {
    struct scanner_struct *scs = p->data;

    LIST_FOREACH(p2, UserItemList.head)
    {
      struct UserConf *uc = p2->data;

      LIST_FOREACH(p3, uc->scanners.head)
      {
        const char *scannername = p3->data;

        /* Add all these masks to scanner */
        if (strcasecmp(scannername, scs->name) == 0)
        {
          LIST_FOREACH(p4, uc->masks.head)
          {
            const char *mask = p4->data;

            if (OPT_DEBUG)
              log_printf("SCAN -> Linking the mask [%s] to scanner [%s]", mask, scannername);

            list_add(xstrdup(mask), node_create(), &scs->masks);
          }

          break;
        }
      }
    }
  }

  /* Initialise negative cache */
  if (OptionsItem.negcache)
  {
    if (OPT_DEBUG >= 2)
      log_printf("SCAN -> Initializing negative cache");

    negcache_init();
  }
}

/* scan_connect
 *
 *    scan_connect is called when m_notice (irc.c) matches a connection
 *    notice and parses the connecting user out of it.
 *
 * Parameters:
 *    user: Parsed items from the connection notice:
 *          user[0] = connecting users nickname
 *          user[1] = connecting users username
 *          user[2] = connecting users hostname
 *          user[3] = connecting users IP
 *          msg     = Original connect notice
 * Return: NONE
 *
 */
void
scan_connect(const char *user[], const char *msg)
{
  node_t *p, *p2;
  int ret;

  /*
   * Have to use MSGLENMAX here because it is unknown what the max size of
   * username/hostname can be.  Some ircds use really mad values for
   * these.
   */
  char hostmask[MSGLENMAX];
  char addrmask[MSGLENMAX];

  /* Check negcache before anything */
  if (negcache_check(user[3]))
  {
    if (OPT_DEBUG)
      log_printf("SCAN -> %s!%s@%s [%s] is negatively cached. Skipping all tests.",
                 user[0], user[1], user[2], user[3]);
    return;
  }

  /* Generate user mask */
  snprintf(hostmask, sizeof(hostmask), "%s!%s@%s", user[0], user[1], user[2]);
  snprintf(addrmask, sizeof(addrmask), "%s!%s@%s", user[0], user[1], user[3]);

  /* Check exempt list now that we have a mask */
  if (scan_checkexempt(hostmask, addrmask))
  {
    if (OPT_DEBUG)
      log_printf("SCAN -> %s [%s] is exempt from scanning", hostmask, user[3]);

    return;
  }

  /* Create scan_struct */
  struct scan_struct *ss = scan_create(user, msg);

  /* Store ss in the remote struct, so that in callbacks we have ss */
  ss->remote->data = ss;

  /* Start checking our DNSBLs */
  if (LIST_SIZE(&OpmItem.blacklists))
    dnsbl_add(ss);

  /* Add ss->remote to all matching scanners */
  LIST_FOREACH(p, SCANNERS.head)
  {
    struct scanner_struct *scs = p->data;

    LIST_FOREACH(p2, scs->masks.head)
    {
      const char *scsmask = p2->data;

      if (match(scsmask, hostmask) == 0)
      {
        if (OPT_DEBUG)
          log_printf("SCAN -> Passing %s to scanner [%s]", hostmask, scs->name);

        if ((ret = opm_scan(scs->scanner, ss->remote)) != OPM_SUCCESS)
        {
          switch (ret)
          {
            case OPM_ERR_NOPROTOCOLS:
              continue;
              break;
            case OPM_ERR_BADADDR:
              if (!strchr(ss->ip, ':'))  /* XXX: hack alert. remove when libopm can deal with IPv6 addresses */
                log_printf("OPM -> Bad address %s [%s]", ss->ip, scs->name);
              break;
            default:
              log_printf("OPM -> Unknown error %s [%s]", ss->ip, scs->name);
              break;
          }
        }
        else
          ++ss->scans;  /* Increase scan count only if OPM_SUCCESS */

        break;  /* Continue to next scanner */
      }
    }
  }

  /* All scanners returned !OPM_SUCCESS and there were no dnsbl checks */
  if (ss->scans == 0)
    scan_free(ss);
}

/* scan_create
 *
 *    Allocate scan struct, including user information and REMOTE
 *    for LIBOPM.
 *
 * Parameters:
 *    user: Parsed items from the connection notice:
 *          user[0] = connecting users nickname
 *          user[1] = connecting users username
 *          user[2] = connecting users hostname
 *          user[3] = connecting users IP
 *          msg     = Original connect notice (used as PROOF)
 *
 * Return: Pointer to new scan_struct
 *
 */
static struct scan_struct *
scan_create(const char *user[], const char *msg)
{
  struct scan_struct *ss = xcalloc(sizeof(*ss));

  ss->irc_nick = xstrdup(user[0]);
  ss->irc_username = xstrdup(user[1]);
  ss->irc_hostname = xstrdup(user[2]);
  ss->ip = xstrdup(user[3]);
  ss->proof = xstrdup(msg);
  ss->remote = opm_remote_create(ss->ip);

  return ss;
}

/* scan_free
 *
 *    Free a scan_struct. This should only be done if the scan struct has
 *    no scans left!
 *
 * Parameters:
 *    ss: scan_struct to free
 *
 * Return: NONE
 */
static void
scan_free(struct scan_struct *ss)
{
  xfree(ss->irc_nick);
  xfree(ss->irc_username);
  xfree(ss->irc_hostname);
  xfree(ss->ip);
  xfree(ss->proof);

  opm_remote_free(ss->remote);
  xfree(ss);
}

/* scan_checkfinished
 *
 *   Check if a scan is complete (ss->scans <= 0)
 *   and free it if need be.
 */
void
scan_checkfinished(struct scan_struct *ss)
{
  if (ss->scans <= 0)
  {
    if (ss->manual_target)
      irc_send("PRIVMSG %s :CHECK -> All tests on %s completed.",
               ss->manual_target, ss->ip);
    else
    {
      if (OPT_DEBUG)
        /* If there was a manual_target, then irc_nick, etc is NULL. */
        log_printf("SCAN -> All tests on %s!%s@%s [%s] complete.",
                   ss->irc_nick, ss->irc_username, ss->irc_hostname, ss->ip);

      /* Scan was a negative */
      if (ss->positive == 0)
        scan_negative(ss);
    }

    scan_free(ss);
  }
}

/* scan_positive
 *
 *    Remote host (defined by ss) has been found positive by one or more
 *    tests.
 *
 * Parameters:
 *    ss: scan_struct containing information regarding positive host
 *    kline: command to send to IRC server to ban the user (see scan_irckline)
 *    type: string of the type of proxy found to be running on the host
 *
 * Return: NONE
 *
 */
void
scan_positive(struct scan_struct *ss, const char *kline, const char *type)
{
  node_t *node;

  /* If already a positive, don't kline/close again */
  if (ss->positive)
    return;

  /* Format KLINE and send to IRC server */
  scan_irckline(ss, kline, type);

  /* Speed up the cleanup procedure */
  /* Close all scans prematurely */
  LIST_FOREACH(node, SCANNERS.head)
  {
    OPM_T *scanner = ((struct scanner_struct *)node->data)->scanner;
    opm_end(scanner, ss->remote);
  }

  /* Set it as a positive to avoid a scan_negative call later on */
  ss->positive = 1;
}

/* scan_open_proxy CALLBACK
 *
 *    Called by libopm when a proxy is verified open.
 *
 * Parameters:
 *    scanner: Scanner that found the open proxy.
 *    remote: Remote struct containing information regarding remote end
 *
 * Return: NONE
 */
static void
scan_open_proxy(OPM_T *scanner, OPM_REMOTE_T *remote, int notused, void *data)
{
  struct scan_struct *ss = remote->data;
  struct scanner_struct *scs = data;

  /* Record that a scan happened */
  scan_log(remote);

  if (ss->manual_target)
  {
    irc_send("PRIVMSG %s :CHECK -> OPEN PROXY %s:%d (%s) [%s]",
             ss->manual_target, remote->ip, remote->port,
             scan_gettype(remote->protocol), scs->name);
    log_printf("SCAN -> OPEN PROXY %s:%d (%s) [%s]", remote->ip,
               remote->port, scan_gettype(remote->protocol), scs->name);
  }
  else
  {
    /* kline and close scan */
    scan_positive(ss, IRCItem.kline, scan_gettype(remote->protocol));

    /* Report to blacklist */
    dnsbl_report(ss);

    irc_send_channels("OPEN PROXY -> %s!%s@%s %s:%d (%s) [%s]",
                      ss->irc_nick, ss->irc_username, ss->irc_hostname, remote->ip,
                      remote->port, scan_gettype(remote->protocol), scs->name);
    log_printf("SCAN -> OPEN PROXY %s!%s@%s %s:%d (%s) [%s]",
               ss->irc_nick, ss->irc_username, ss->irc_hostname, remote->ip,
               remote->port, scan_gettype(remote->protocol), scs->name);
  }

  /* Record the proxy for stats purposes */
  stats_openproxy(remote->protocol);
}

/* scan_negotiation_failed CALLBACK
 *
 *    Called by libopm when negotiation of a specific protocol failed.
 *
 * Parameters:
 *    scanner: Scanner where the negotiation failed.
 *    remote: Remote struct containing information regarding remote end
 *
 * Return: NONE
 *
 */
static void
scan_negotiation_failed(OPM_T *scanner, OPM_REMOTE_T *remote, int notused, void *data)
{
  const struct scanner_struct *scs = data;

  /* Record that a scan happened */
  scan_log(remote);

  if (OPT_DEBUG)
    log_printf("SCAN -> Negotiation failed %s:%d (%s) [%s] (%d bytes read)",
               remote->ip, remote->port, scan_gettype(remote->protocol), scs->name,
               remote->bytes_read);
}

/* scan_timeout CALLBACK
 *
 *    Called by libopm when the negotiation of a specific protocol timed out.
 *
 * Parameters:
 *    scanner: Scanner where the connection timed out.
 *    remote: Remote struct containing information regarding remote end
 *
 * Return: NONE
 *
 */
static void
scan_timeout(OPM_T *scanner, OPM_REMOTE_T *remote, int notused, void *data)
{
  const struct scanner_struct *scs = data;

  /* Record that a scan happened */
  scan_log(remote);

  if (OPT_DEBUG)
    log_printf("SCAN -> Negotiation timed out %s:%d (%s) [%s] (%d bytes read)",
               remote->ip, remote->port, scan_gettype(remote->protocol), scs->name,
               remote->bytes_read);
}

/* scan_end CALLBACK
 *
 *    Called by libopm when a specific SCAN has completed (all protocols in
 *    that scan).
 *
 * Parameters:
 *    scanner: Scanner the scan ended on.
 *    remote: Remote struct containing information regarding remote end
 *
 * Return: NONE
 */
static void
scan_end(OPM_T *scanner, OPM_REMOTE_T *remote, int notused, void *data)
{
  struct scan_struct *ss = remote->data;
  struct scanner_struct *scs = data;

  if (OPT_DEBUG)
    log_printf("SCAN -> Scan %s [%s] completed", remote->ip, scs->name);

  --ss->scans;
  scan_checkfinished(ss);
}

/* scan_handle_error CALLBACK
 *
 *    Called by libopm when an error occurs with a specific connection. This
 *    does not mean the entire scan has ended.
 *
 * Parameters:
 *    scanner: Scanner where the error occured.
 *    remote: Remote struct containing information regarding remote end
 *    err: OPM_ERROR code describing the error.
 *
 * Return: NONE
 */
static void
scan_handle_error(OPM_T *scanner, OPM_REMOTE_T *remote, int err, void *data)
{
  struct scan_struct *ss = remote->data;
  struct scanner_struct *scs = data;

  switch (err)
  {
    case OPM_ERR_MAX_READ:
      if (OPT_DEBUG >= 2)
        log_printf("SCAN -> Max read on %s:%d (%s) [%s] (%d bytes read)",
                   remote->ip, remote->port, scan_gettype(remote->protocol),
                   scs->name, remote->bytes_read);

      if (ss->manual_target)
        irc_send("PRIVMSG %s :CHECK -> Negotiation failed %s:%d (%s) "
                 "[%s] (%d bytes read)", ss->manual_target,
                 remote->ip, remote->port, scan_gettype(remote->protocol),
                 scs->name, remote->bytes_read);
      break;
    case OPM_ERR_BIND:
      log_printf("SCAN -> Bind error on %s:%d (%s) [%s]", remote->ip,
                 remote->port, scan_gettype(remote->protocol), scs->name);

      if (ss->manual_target)
        irc_send("PRIVMSG %s :CHECK -> Bind error on %s:%d (%s) [%s]",
                 ss->manual_target, remote->ip, remote->port,
                 scan_gettype(remote->protocol), scs->name);
      break;
    case OPM_ERR_NOFD:
      log_printf("SCAN -> File descriptor allocation error %s:%d (%s) "
                "[%s]", remote->ip, remote->port,
                scan_gettype(remote->protocol), scs->name);

      if (ss->manual_target)
        irc_send("PRIVMSG %s :CHECK -> Scan failed %s:%d (%s) [%s] "
                 "(file descriptor allocation error)",
                 ss->manual_target, remote->ip, remote->port,
                 scan_gettype(remote->protocol), scs->name);
      break;
    default:  /* Unknown Error! */
      if (OPT_DEBUG)
        log_printf("SCAN -> Unknown error %s:%d (%s) [%s]", remote->ip,
                   remote->port, scan_gettype(remote->protocol), scs->name);
      break;
  }
}

/* scan_negative
 *
 *    Remote host (defined by ss) has passed all tests.
 *
 * Parameters:
 *    ss: scan_struct containing information regarding negative host.
 *
 * Return: NONE
 *
 */
static void
scan_negative(const struct scan_struct *ss)
{
  /* Insert IP in negcache */
  if (OptionsItem.negcache)
  {
    if (OPT_DEBUG >= 2)
      log_printf("SCAN -> Adding %s to negative cache", ss->ip);

    negcache_insert(ss->ip);
  }
}

/* scan_irckline
 *
 *    ss has been found as a positive host and is to be klined.
 *    Format a kline message using the kline message provided
 *    as a format, then pass it to irc_send() to be sent to the remote server.
 *
 * Parameters:
 *    ss: scan_struct containing information regarding host to be klined
 *    format: kline message to format
 *    type: type of proxy found (%t format character)
 *
 * Return: NONE
 */
static void
scan_irckline(const struct scan_struct *ss, const char *format, const char *type)
{
  char message[MSGLENMAX] = "";  /* OUTPUT */

  unsigned int pos = 0;   /* position in format */
  unsigned int len = 0;   /* position in message */
  unsigned int size = 0;  /* temporary size buffer */
  struct kline_format_assoc
  {
    const char key;
    const char *data;
  } table[] =
  {
    { 'i',  ss->ip           },
    { 'h',  ss->irc_hostname },
    { 'u',  ss->irc_username },
    { 'n',  ss->irc_nick     },
    { 't',  type             },
    { '\0', NULL             }
  };

  /*
   * Copy format to message character by character, inserting any matching
   * data after %.
   */
  while (format[pos] != '\0' && len < (MSGLENMAX - 2))
  {
    switch (format[pos])
    {
      case '%':
        /* % is the last char in the string, move on */
        if (format[pos + 1] == '\0')
          continue;

        /* %% escapes % and becomes % */
        if (format[pos + 1] == '%')
        {
          message[len++] = '%';
          ++pos;  /* Skip past the escaped % */
          break;
        }

        /* Safe to check against table now */
        for (const struct kline_format_assoc *tab = table; tab->key; ++tab)
        {
          if (tab->key == format[pos + 1])
          {
            size = strlen(tab->data);

            /* Check if the new string can fit! */
            if ((size + len) > (MSGLENMAX - 1))
              break;
            else
            {
              strlcat(message, tab->data, sizeof(message));
              len += size;
            }
          }
        }

        /* Skip key character */
        ++pos;
        break;

        default:
          message[len++] = format[pos];
          message[len] = '\0';
          break;
    }

    /* Continue to next character in format */
    ++pos;
  }

  irc_send("%s", message);
}

/* scan_manual
 *
 *    Create a manual scan. A manual scan is a scan where the
 *    scan_struct contains a manual_target pointer.
 */
void
scan_manual(char *param, const char *target)
{
  char buf[INET6_ADDRSTRLEN];
  const void *addr = NULL;
  const char *ip = NULL;
  char *scannername;
  node_t *node;
  int ret, n;
  struct sockaddr_storage storage;
  socklen_t storage_len = 0;

  /* If there were no parameters sent, simply alert the user and return */
  if (param == NULL)
  {
    irc_send("PRIVMSG %s :OPM -> Invalid parameters.", target);
    return;
  }

  /*
   * Try to extract a scanner name from param, otherwise we'll be
   * adding to all scanners
   */
  ip = param;

  if ((scannername = strchr(param, ' ')))
  {
    *scannername = '\0';
    scannername++;
  }

  memset(&storage, 0, sizeof(storage));

  if ((addr = firedns_resolveip6(ip)))
  {
    struct sockaddr_in6 *in = (struct sockaddr_in6 *)&storage;

    storage_len = sizeof(*in);
    storage.ss_family = AF_INET6;
    memcpy(&in->sin6_addr, addr, sizeof(in->sin6_addr));
  }
  else if ((addr = firedns_resolveip4(ip)))
  {
    struct sockaddr_in *in = (struct sockaddr_in *)&storage;

    storage_len = sizeof(*in);
    storage.ss_family = AF_INET;
    memcpy(&in->sin_addr, addr, sizeof(in->sin_addr));
  }
  else
  {
    irc_send("PRIVMSG %s :CHECK -> Error resolving host '%s': %s",
             target, ip, firedns_strerror(firedns_errno));
    return;
  }

  if ((n = getnameinfo((const struct sockaddr *)&storage, storage_len, buf, sizeof(buf), NULL, 0, NI_NUMERICHOST)))
  {
    irc_send("PRIVMSG %s :CHECK -> invalid address: %s",
             target, gai_strerror(n));
    return;
  }

  ip = buf;

  struct scan_struct *ss = xcalloc(sizeof(*ss));
  ss->ip = xstrdup(ip);
  ss->remote = opm_remote_create(ss->ip);
  ss->remote->data = ss;
  ss->manual_target = target;

  if (scannername)
    irc_send("PRIVMSG %s :CHECK -> Checking '%s' for open proxies [%s]",
             target, ss->ip, scannername);
  else
    irc_send("PRIVMSG %s :CHECK -> Checking '%s' for open proxies on all scanners",
             target, ss->ip);

  if (LIST_SIZE(&OpmItem.blacklists))
    dnsbl_add(ss);

  /* Add ss->remote to all scanners */
  LIST_FOREACH(node, SCANNERS.head)
  {
    struct scanner_struct *scs = node->data;

    /*
     * If we have a scannername, only allow that scanner
     * to be used
     */
    if (scannername)
      if (strcasecmp(scannername, scs->name))
        continue;

    if (OPT_DEBUG)
      log_printf("SCAN -> Passing %s to scanner [%s] (MANUAL SCAN)", ss->ip, scs->name);

    if ((ret = opm_scan(scs->scanner, ss->remote)) != OPM_SUCCESS)
    {
      switch (ret)
      {
        case OPM_ERR_NOPROTOCOLS:
          break;
        case OPM_ERR_BADADDR:
          if (!strchr(ss->ip, ':'))  /* XXX: hack alert. remove when libopm can deal with IPv6 addresses */
            irc_send("PRIVMSG %s :OPM -> Bad address %s [%s]",
                     ss->manual_target, ss->ip, scs->name);
          break;
        default:
          irc_send("PRIVMSG %s :OPM -> Unknown error %s [%s]",
                   ss->manual_target, ss->ip, scs->name);
          break;
      }
    }
    else
      ++ss->scans;  /* Increase scan count only if OPM_SUCCESS */
  }

  /*
   * If all of the scanners gave !OPM_SUCCESS and there were no dnsbl checks,
   * cleanup here
   */
  if (ss->scans == 0)
  {
    if (scannername)
      irc_send("PRIVMSG %s :CHECK -> No such scanner '%s', or '%s' has 0 protocols.",
               ss->manual_target, scannername, scannername);

    irc_send("PRIVMSG %s :CHECK -> No scans active on '%s', aborting scan.",
             ss->manual_target, ss->ip);
    scan_free(ss);
  }
}

/* scan_log
 *
 *    Log the fact that a given ip/port/protocol has just been scanned, if the
 *    user has asked for this to be logged.
 *
 * Parameters:
 *     remote: OPM_REMOTE_T for the remote end
 */
static void
scan_log(OPM_REMOTE_T *remote)
{
  struct scan_struct *ss = remote->data;

  if (!(OptionsItem.scanlog && scanlogfile))
    return;

  fprintf(scanlogfile, "[%s] %s:%d (%s) \"%s\"\n", date_iso8601(0), remote->ip,
          remote->port, scan_gettype(remote->protocol), ss->proof);
  fflush(scanlogfile);
}