nmap/libnetutil/NetBlock.h

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#ifndef NETUTIL_NETBLOCK_H
#define NETUTIL_NETBLOCK_H

#include <string>
#include <list>
#include <vector>
#include "massdns.h"
class NetBlock {
public:
  virtual ~NetBlock() {}
  NetBlock(bool r_a=false, const char *dev=NULL)
    : resolve_all(r_a), device(dev)
  {
    current_addr = resolvedaddrs.begin();
  }
  std::string hostname;
  std::list<struct sockaddr_storage> resolvedaddrs;
  std::list<struct sockaddr_storage> unscanned_addrs;
  std::list<struct sockaddr_storage>::const_iterator current_addr;

  /* Parses an expression such as 192.168.0.0/16, 10.1.0-5.1-254, or
     fe80::202:e3ff:fe14:1102/112 and returns a newly allocated NetBlock. The af
     parameter is AF_INET or AF_INET6. Returns NULL in case of error. */
  static NetBlock *parse_expr(const char *target_expr, int af, std::vector<DNS::Request> &requests, bool resolve_all=false, const char *device=NULL);

  bool is_resolved_address(const struct sockaddr_storage *ss) const;

  /* For NetBlock subclasses that need to "resolve" themselves into a different
   * NetBlock subclass, override this method. Otherwise, it's safe to reassign
   * the return value to the pointer that this method was called through.
   * On error, return NULL. */
  virtual NetBlock *resolve(const DNS::Request &req) { return this; }
  virtual void reject_last_host() {}
  virtual bool next(struct sockaddr_storage *ss, size_t *sslen) = 0;
  virtual void apply_netmask(int bits) = 0;
  virtual std::string str() const = 0;
protected:
  bool resolve_all;
  const char *device;
};

class NetBlockRandomIPv4 : public NetBlock {
public:
  NetBlockRandomIPv4();

  void reject_last_host() { if (!infinite) count++; }
  void set_num_random(unsigned long num) {
    if (num == 0)
      infinite = true;
    else
      count = num;
  }
  bool next(struct sockaddr_storage *ss, size_t *sslen);
  void apply_netmask(int bits) {}
  std::string str() const {return "Random IPv4 addresses";}

private:
  struct sockaddr_in base;
  unsigned long count;
  bool infinite;
};

#endif