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/***************************************************************************
* ncat_core.h *
***********************IMPORTANT NMAP LICENSE TERMS************************
*
* The Nmap Security Scanner is (C) 1996-2023 Nmap Software LLC ("The Nmap
* Project"). Nmap is also a registered trademark of the Nmap Project.
*
* This program is distributed under the terms of the Nmap Public Source
* License (NPSL). The exact license text applying to a particular Nmap
* release or source code control revision is contained in the LICENSE
* file distributed with that version of Nmap or source code control
* revision. More Nmap copyright/legal information is available from
* https://nmap.org/book/man-legal.html, and further information on the
* NPSL license itself can be found at https://nmap.org/npsl/ . This
* header summarizes some key points from the Nmap license, but is no
* substitute for the actual license text.
*
* Nmap is generally free for end users to download and use themselves,
* including commercial use. It is available from https://nmap.org.
*
* The Nmap license generally prohibits companies from using and
* redistributing Nmap in commercial products, but we sell a special Nmap
* OEM Edition with a more permissive license and special features for
* this purpose. See https://nmap.org/oem/
*
* If you have received a written Nmap license agreement or contract
* stating terms other than these (such as an Nmap OEM license), you may
* choose to use and redistribute Nmap under those terms instead.
*
* The official Nmap Windows builds include the Npcap software
* (https://npcap.com) for packet capture and transmission. It is under
* separate license terms which forbid redistribution without special
* permission. So the official Nmap Windows builds may not be redistributed
* without special permission (such as an Nmap OEM license).
*
* Source is provided to this software because we believe users have a
* right to know exactly what a program is going to do before they run it.
* This also allows you to audit the software for security holes.
*
* Source code also allows you to port Nmap to new platforms, fix bugs, and add
* new features. You are highly encouraged to submit your changes as a Github PR
* or by email to the dev@nmap.org mailing list for possible incorporation into
* the main distribution. Unless you specify otherwise, it is understood that
* you are offering us very broad rights to use your submissions as described in
* the Nmap Public Source License Contributor Agreement. This is important
* because we fund the project by selling licenses with various terms, and also
* because the inability to relicense code has caused devastating problems for
* other Free Software projects (such as KDE and NASM).
*
* The free version of Nmap 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. Warranties,
* indemnification and commercial support are all available through the
* Npcap OEM program--see https://nmap.org/oem/
*
***************************************************************************/
/* $Id$ */
#ifndef NCAT_CORE_H
#define NCAT_CORE_H
#include "nsock.h"
#include "nbase.h"
#include "util.h"
#include "sockaddr_u.h"
/* Maximum size of the srcaddrs array. In this case two because we can only have
a IPV4 INADDR_ANY and a IPV6 in6addr_any at most or a user defined address */
#define NUM_LISTEN_ADDRS 2
/* Structure to store a linked list of resolved addresses. */
struct sockaddr_list {
union sockaddr_u addr;
size_t addrlen;
struct sockaddr_list* next;
};
extern union sockaddr_u listenaddrs[NUM_LISTEN_ADDRS];
extern int num_listenaddrs;
extern union sockaddr_u srcaddr;
extern size_t srcaddrlen;
extern struct sockaddr_list *targetaddrs;
enum exec_mode {
EXEC_PLAIN,
EXEC_SHELL,
EXEC_LUA,
};
/* Proxy DNS resolution options (mask bits) */
#define PROXYDNS_LOCAL 1
#define PROXYDNS_REMOTE 2
struct options {
unsigned int portno;
int verbose;
int debug;
char *target;
int af;
/* IPPROTO_TCP, IPPROTO_SCTP, or IPPROTO_UDP */
int proto;
int broker;
int listen;
int keepopen;
int sendonly;
int recvonly;
int noshutdown;
int telnet;
int linedelay;
int chat;
int nodns;
const char *normlog;
const char *hexlog;
int normlogfd;
int hexlogfd;
int append;
int idletimeout;
int crlf;
/* Were any hosts specifically allowed? If so, deny all others. */
int allow;
int deny;
struct addrset *allowset;
struct addrset *denyset;
int httpserver;
int nsock_engine;
/* Output messages useful for testing to stderr? */
int test;
/* Loose source-routing stuff */
struct in_addr srcrtes[8];
int numsrcrtes;
int srcrteptr;
/* Maximum number of simultaneous connections */
int conn_limit;
int conntimeout;
/* When execmode == EXEC_LUA, cmdexec is the name of the file to run. */
char *cmdexec;
enum exec_mode execmode;
char *proxy_auth;
char *proxytype;
char *proxyaddr;
int proxydns;
int ssl;
char *sslcert;
char *sslkey;
int sslverify;
char *ssltrustfile;
char *sslciphers;
char* sslservername;
char *sslalpn;
int zerobyte;
};
extern struct options o;
/* The time the program was started, for exit statistics in connect mode. */
extern struct timeval start_time;
/* Initializes global options to their default values. */
void options_init(void);
/* Resolves the given hostname or IP address with getaddrinfo, and stores the
first result (if any) in *ss and *sslen. The value of port will be set in the
appropriate place in *ss; set to 0 if you don't care. af may be AF_UNSPEC, in
which case getaddrinfo may return e.g. both IPv4 and IPv6 results; which one
is first depends on the system configuration. Returns 0 on success, or a
getaddrinfo return code (suitable for passing to gai_strerror) on failure.
*ss and *sslen are always defined when this function returns 0.
If the global o.nodns is true, then do not resolve any names with DNS. */
int resolve(const char *hostname, unsigned short port,
struct sockaddr_storage *ss, size_t *sslen, int af);
/* Resolves the given hostname or IP address with getaddrinfo, and stores the
first result (if any) in *ss and *sslen. The value of port will be set in the
appropriate place in *ss; set to 0 if you don't care. af may be AF_UNSPEC, in
which case getaddrinfo may return e.g. both IPv4 and IPv6 results; which one
is first depends on the system configuration. Returns 0 on success, or a
getaddrinfo return code (suitable for passing to gai_strerror) on failure.
*ss and *sslen are always defined when this function returns 0.
Resolve the hostname with DNS only if global o.proxydns includes PROXYDNS_LOCAL. */
int proxyresolve(const char *hostname, unsigned short port,
struct sockaddr_storage *ss, size_t *sslen, int af);
/* Resolves the given hostname or IP address with getaddrinfo, and stores
all results into a linked list.
The rest of behavior is same as resolve(). */
int resolve_multi(const char *hostname, unsigned short port,
struct sockaddr_list *sl, int af);
void free_sockaddr_list(struct sockaddr_list *sl);
int fdinfo_close(struct fdinfo *fdn);
int fdinfo_recv(struct fdinfo *fdn, char *buf, size_t size);
int fdinfo_send(struct fdinfo *fdn, const char *buf, size_t size);
int fdinfo_pending(struct fdinfo *fdn);
int ncat_recv(struct fdinfo *fdn, char *buf, size_t size, int *pending);
int ncat_send(struct fdinfo *fdn, const char *buf, size_t size);
/* Broadcast a message to all the descriptors in fds. Returns -1 if any of the
sends failed. */
extern int ncat_broadcast(fd_set *fds, const fd_list_t *fdlist, const char *msg, size_t size);
/* Do telnet WILL/WONT DO/DONT negotiations */
extern void dotelnet(int s, unsigned char *buf, size_t bufsiz);
/* sleep(), usleep(), msleep(), Sleep() -- all together now, "portability".
*
* There is no upper or lower limit to the delayval, so if you pass in a short
* length of time <100ms, then you're likely going to get odd results.
* This is because the Linux timeslice is 10ms-200ms. So don't expect
* it to return for at least that long.
*
* Block until the specified time has elapsed, then return 1.
*/
extern int ncat_delay_timer(int delayval);
/* Open a logfile for writing.
* Return the open file descriptor. */
extern int ncat_openlog(const char *logfile, int append);
extern void ncat_log_send(const char *data, size_t len);
extern void ncat_log_recv(const char *data, size_t len);
extern int ncat_hostaccess(char *matchaddr, char *filename, char *remoteip);
/* Make it so that line endings read from a console are always \n (not \r\n).
Defined in ncat_posix.c and ncat_win.c. */
extern void set_lf_mode(void);
extern int getaddrfamily(const char *addr);
extern int setenv_portable(const char *name, const char *value);
extern void setup_environment(struct fdinfo *fdinfo);
#endif
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