/*************************************************************************** * nsock_connect.c -- This contains the functions for requesting TCP * * connections from the nsock parallel socket event library * ***********************IMPORTANT NSOCK LICENSE TERMS*********************** * * * The nsock parallel socket event library is (C) 1999-2012 Insecure.Com * * LLC This library is free software; you may redistribute and/or * * modify it under the terms of the GNU General Public License as * * published by the Free Software Foundation; Version 2. This guarantees * * your right to use, modify, and redistribute this software under certain * * conditions. If this license is unacceptable to you, Insecure.Com LLC * * may be willing to sell alternative licenses (contact * * sales@insecure.com ). * * * * As a special exception to the GPL terms, Insecure.Com LLC grants * * permission to link the code of this program with any version of the * * OpenSSL library which is distributed under a license identical to that * * listed in the included docs/licenses/OpenSSL.txt file, and distribute * * linked combinations including the two. You must obey the GNU GPL in all * * respects for all of the code used other than OpenSSL. If you modify * * this file, you may extend this exception to your version of the file, * * but you are not obligated to do so. * * * * If you received these files with a written license agreement stating * * terms other than the (GPL) terms above, then that alternative license * * agreement takes precedence over this comment. * * * * 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 (none * * have been found so far). * * * * Source code also allows you to port Nmap to new platforms, fix bugs, * * and add new features. You are highly encouraged to send your changes * * to the dev@nmap.org mailing list for possible incorporation into the * * main distribution. By sending these changes to Fyodor or one of the * * Insecure.Org development mailing lists, or checking them into the Nmap * * source code repository, it is understood (unless you specify otherwise) * * that you are offering the Nmap Project (Insecure.Com LLC) the * * unlimited, non-exclusive right to reuse, modify, and relicense the * * code. Nmap will always be available Open Source, but this is important * * because the inability to relicense code has caused devastating problems * * for other Free Software projects (such as KDE and NASM). We also * * occasionally relicense the code to third parties as discussed above. * * If you wish to specify special license conditions of your * * contributions, just say so when you send them. * * * * 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 v2.0 for more details * * (http://www.gnu.org/licenses/gpl-2.0.html). * * * ***************************************************************************/ /* $Id$ */ #include "nsock.h" #include "nsock_internal.h" #include "nsock_log.h" #include "nsock_proxy.h" #include "netutils.h" #include #include #include static int mksock_bind_addr(mspool *ms, msiod *iod) { int rc; int one = 1; rc = setsockopt(iod->sd, SOL_SOCKET, SO_REUSEADDR, (const char *)&one, sizeof(one)); if (rc == -1) { int err = socket_errno(); nsock_log_error(ms, "Setting of SO_REUSEADDR failed (#%li): %s (%d)", iod->id, socket_strerror(err), err); } nsock_log_info(ms, "Binding to %s (IOD #%li)", get_localaddr_string(iod), iod->id); rc = bind(iod->sd, (struct sockaddr *)&iod->local, (int) iod->locallen); if (rc == -1) { int err = socket_errno(); nsock_log_error(ms, "Bind to %s failed (IOD #%li): %s (%d)", get_localaddr_string(iod), iod->id, socket_strerror(err), err); } return 0; } static int mksock_set_ipopts(mspool *ms, msiod *iod) { int rc; errno = 0; rc = setsockopt(iod->sd, IPPROTO_IP, IP_OPTIONS, (const char *)iod->ipopts, iod->ipoptslen); if (rc == -1) { int err = socket_errno(); nsock_log_error(ms, "Setting of IP options failed (IOD #%li): %s (%d)", iod->id, socket_strerror(err), err); } return 0; } static int mksock_bind_device(mspool *ms, msiod *iod) { int rc; rc = socket_bindtodevice(iod->sd, ms->device); if (!rc) { int err = socket_errno(); if (err != EPERM) nsock_log_error(ms, "Setting of SO_BINDTODEVICE failed (IOD #%li): %s (%d)", iod->id, socket_strerror(err), err); else nsock_log_debug_all(ms, "Setting of SO_BINDTODEVICE failed (IOD #%li): %s (%d)", iod->id, socket_strerror(err), err); } return 0; } static int mksock_set_broadcast(mspool *ms, msiod *iod) { int rc; int one = 1; rc = setsockopt(iod->sd, SOL_SOCKET, SO_BROADCAST, (const char *)&one, sizeof(one)); if (rc == -1) { int err = socket_errno(); nsock_log_error(ms, "Setting of SO_BROADCAST failed (IOD #%li): %s (%d)", iod->id, socket_strerror(err), err); } return 0; } /* Create the actual socket (nse->iod->sd) underlying the iod. This unblocks the * socket, binds to the localaddr address, sets IP options, and sets the * broadcast flag. Trying to change these functions after making this call will * not have an effect. This function needs to be called before you try to read * or write on the iod. */ static int nsock_make_socket(mspool *ms, msiod *iod, int family, int type, int proto) { /* inheritable_socket is from nbase */ iod->sd = (int)inheritable_socket(family, type, proto); if (iod->sd == -1) { perror("Socket troubles"); return -1; } unblock_socket(iod->sd); iod->lastproto = proto; if (iod->locallen) mksock_bind_addr(ms, iod); if (iod->ipoptslen && family == AF_INET) mksock_set_ipopts(ms, iod); if (ms->device) mksock_bind_device(ms, iod); if (ms->broadcast && type != SOCK_STREAM) mksock_set_broadcast(ms, iod); /* mksock_* functions can raise warnings/errors * but we don't let them stop us for now. */ return iod->sd; } int nsock_setup_udp(nsock_pool nsp, nsock_iod ms_iod, int af) { mspool *ms = (mspool *)nsp; msiod *nsi = (msiod *)ms_iod; assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nsock_log_info(ms, "UDP unconnected socket (IOD #%li)", nsi->id); if (nsock_make_socket(ms, nsi, af, SOCK_DGRAM, IPPROTO_UDP) == -1) return -1; return nsi->sd; } /* This does the actual logistics of requesting a TCP connection. It is shared * by nsock_connect_tcp and nsock_connect_ssl */ void nsock_connect_internal(mspool *ms, msevent *nse, int type, int proto, struct sockaddr_storage *ss, size_t sslen, unsigned short port) { struct sockaddr_in *sin; #if HAVE_IPV6 struct sockaddr_in6 *sin6; #endif msiod *iod = nse->iod; if (iod->px_ctx /* proxy enabled */ && proto == IPPROTO_TCP /* restrict proxying to TCP connections */ && (nse->handler != nsock_proxy_ev_dispatch)) { /* for reentrancy */ struct proxy_node *current; nsock_log_debug_all(ms, "TCP connection request (EID %lu) redirected through proxy chain", (long)nse->id); current = proxy_ctx_node_current(iod->px_ctx); assert(current != NULL); memcpy(&iod->px_ctx->target_ss, ss, sslen); iod->px_ctx->target_sslen = sslen; iod->px_ctx->target_port = port; ss = ¤t->ss; sslen = current->sslen; port = current->port; iod->px_ctx->target_handler = nse->handler; nse->handler = nsock_proxy_ev_dispatch; iod->px_ctx->target_ev_type = nse->type; nse->type = NSE_TYPE_CONNECT; } sin = (struct sockaddr_in *)ss; #if HAVE_IPV6 sin6 = (struct sockaddr_in6 *)ss; #endif /* Now it is time to actually attempt the connection */ if (nsock_make_socket(ms, iod, ss->ss_family, type, proto) == -1) { nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = socket_errno(); } else { if (ss->ss_family == AF_INET) { sin->sin_port = htons(port); } #if HAVE_IPV6 else if (ss->ss_family == AF_INET6) { sin6->sin6_port = htons(port); } #endif #if HAVE_SYS_UN_H else if (ss->ss_family == AF_UNIX) { } #endif else { fatal("Unknown address family %d\n", ss->ss_family); } assert(sslen <= sizeof(iod->peer)); if (&iod->peer != ss) memcpy(&iod->peer, ss, sslen); iod->peerlen = sslen; if (connect(iod->sd, (struct sockaddr *)ss, sslen) == -1) { int err = socket_errno(); if (proto == IPPROTO_UDP || (err != EINPROGRESS && err != EAGAIN)) { nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = err; } } /* The callback handle_connect_result handles the connection once it completes. */ } } #if HAVE_SYS_UN_H /* Request a UNIX domain sockets connection to the same system (by path to socket). * This function connects to the socket of type SOCK_STREAM. ss should be a * sockaddr_storage, sockaddr_un as appropriate (just like what you would pass to * connect). sslen should be the sizeof the structure you are passing in. */ nsock_event_id nsock_connect_unixsock_stream(nsock_pool nsp, nsock_iod nsiod, nsock_ev_handler handler, int timeout_msecs, void *userdata, struct sockaddr *saddr, size_t sslen) { msiod *nsi = (msiod *)nsiod; mspool *ms = (mspool *)nsp; msevent *nse; struct sockaddr_storage *ss = (struct sockaddr_storage *)saddr; assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nse = msevent_new(ms, NSE_TYPE_CONNECT, nsi, timeout_msecs, handler, userdata); assert(nse); nsock_log_info(ms, "UNIX domain socket (STREAM) connection requested to %s (IOD #%li) EID %li", get_unixsock_path(ss), nsi->id, nse->id); nsock_connect_internal(ms, nse, SOCK_STREAM, 0, ss, sslen, 0); nsp_add_event(ms, nse); return nse->id; } /* Request a UNIX domain sockets connection to the same system (by path to socket). * This function connects to the socket of type SOCK_DGRAM. ss should be a * sockaddr_storage, sockaddr_un as appropriate (just like what you would pass to * connect). sslen should be the sizeof the structure you are passing in. */ nsock_event_id nsock_connect_unixsock_datagram(nsock_pool nsp, nsock_iod nsiod, nsock_ev_handler handler, void *userdata, struct sockaddr *saddr, size_t sslen) { msiod *nsi = (msiod *)nsiod; mspool *ms = (mspool *)nsp; msevent *nse; struct sockaddr_storage *ss = (struct sockaddr_storage *)saddr; assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nse = msevent_new(ms, NSE_TYPE_CONNECT, nsi, -1, handler, userdata); assert(nse); nsock_log_info(ms, "UNIX domain socket (DGRAM) connection requested to %s (IOD #%li) EID %li", get_unixsock_path(ss), nsi->id, nse->id); nsock_connect_internal(ms, nse, SOCK_DGRAM, 0, ss, sslen, 0); nsp_add_event(ms, nse); return nse->id; } #endif /* HAVE_SYS_UN_H */ /* Request a TCP connection to another system (by IP address). The in_addr is * normal network byte order, but the port number should be given in HOST BYTE * ORDER. ss should be a sockaddr_storage, sockaddr_in6, or sockaddr_in as * appropriate (just like what you would pass to connect). sslen should be the * sizeof the structure you are passing in. */ nsock_event_id nsock_connect_tcp(nsock_pool nsp, nsock_iod ms_iod, nsock_ev_handler handler, int timeout_msecs, void *userdata, struct sockaddr *saddr, size_t sslen, unsigned short port) { msiod *nsi = (msiod *)ms_iod; mspool *ms = (mspool *)nsp; msevent *nse; struct sockaddr_storage *ss = (struct sockaddr_storage *)saddr; assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nse = msevent_new(ms, NSE_TYPE_CONNECT, nsi, timeout_msecs, handler, userdata); assert(nse); nsock_log_info(ms, "TCP connection requested to %s:%hu (IOD #%li) EID %li", inet_ntop_ez(ss, sslen), port, nsi->id, nse->id); /* Do the actual connect() */ nsock_connect_internal(ms, nse, SOCK_STREAM, IPPROTO_TCP, ss, sslen, port); nsp_add_event(ms, nse); return nse->id; } /* Request an SCTP association to another system (by IP address). The in_addr * is normal network byte order, but the port number should be given in HOST * BYTE ORDER. ss should be a sockaddr_storage, sockaddr_in6, or sockaddr_in as * appropriate (just like what you would pass to connect). sslen should be the * sizeof the structure you are passing in. */ nsock_event_id nsock_connect_sctp(nsock_pool nsp, nsock_iod ms_iod, nsock_ev_handler handler, int timeout_msecs, void *userdata, struct sockaddr *saddr, size_t sslen, unsigned short port) { msiod *nsi = (msiod *)ms_iod; mspool *ms = (mspool *)nsp; msevent *nse; struct sockaddr_storage *ss = (struct sockaddr_storage *)saddr; assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nse = msevent_new(ms, NSE_TYPE_CONNECT, nsi, timeout_msecs, handler, userdata); assert(nse); nsock_log_info(ms, "SCTP association requested to %s:%hu (IOD #%li) EID %li", inet_ntop_ez(ss, sslen), port, nsi->id, nse->id); /* Do the actual connect() */ nsock_connect_internal(ms, nse, SOCK_STREAM, IPPROTO_SCTP, ss, sslen, port); nsp_add_event(ms, nse); return nse->id; } /* Request an SSL over TCP/SCTP connection to another system (by IP address). * The in_addr is normal network byte order, but the port number should be given * in HOST BYTE ORDER. This function will call back only after it has made the * connection AND done the initial SSL negotiation. From that point on, you use * the normal read/write calls and decryption will happen transparently. ss * should be a sockaddr_storage, sockaddr_in6, or sockaddr_in as appropriate * (just like what you would pass to connect). sslen should be the sizeof the * structure you are passing in. */ nsock_event_id nsock_connect_ssl(nsock_pool nsp, nsock_iod nsiod, nsock_ev_handler handler, int timeout_msecs, void *userdata, struct sockaddr *saddr, size_t sslen, int proto, unsigned short port, nsock_ssl_session ssl_session) { #ifndef HAVE_OPENSSL fatal("nsock_connect_ssl called - but nsock was built w/o SSL support. QUITTING"); return (nsock_event_id)0; /* UNREACHED */ #else struct sockaddr_storage *ss = (struct sockaddr_storage *)saddr; msiod *nsi = (msiod *)nsiod; mspool *ms = (mspool *)nsp; msevent *nse; if (!ms->sslctx) nsp_ssl_init(ms); assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nse = msevent_new(ms, NSE_TYPE_CONNECT_SSL, nsi, timeout_msecs, handler, userdata); assert(nse); /* Set our SSL_SESSION so we can benefit from session-id reuse. */ nsi_set_ssl_session(nsi, (SSL_SESSION *)ssl_session); nsock_log_info(ms, "SSL connection requested to %s:%hu/%s (IOD #%li) EID %li", inet_ntop_ez(ss, sslen), port, (proto == IPPROTO_TCP ? "tcp" : "sctp"), nsi->id, nse->id); /* Do the actual connect() */ nsock_connect_internal(ms, nse, SOCK_STREAM, proto, ss, sslen, port); nsp_add_event(ms, nse); return nse->id; #endif /* HAVE_OPENSSL */ } /* Request ssl connection over already established connection. nsiod must be * socket that is already connected to target using nsock_connect_tcp or * nsock_connect_sctp. All parameters have the same meaning as in * 'nsock_connect_ssl' */ nsock_event_id nsock_reconnect_ssl(nsock_pool nsp, nsock_iod nsiod, nsock_ev_handler handler, int timeout_msecs, void *userdata, nsock_ssl_session ssl_session) { #ifndef HAVE_OPENSSL fatal("nsock_reconnect_ssl called - but nsock was built w/o SSL support. QUITTING"); return (nsock_event_id) 0; /* UNREACHED */ #else msiod *nsi = (msiod *)nsiod; mspool *ms = (mspool *)nsp; msevent *nse; if (!ms->sslctx) nsp_ssl_init(ms); nse = msevent_new(ms, NSE_TYPE_CONNECT_SSL, nsi, timeout_msecs, handler, userdata); assert(nse); /* Set our SSL_SESSION so we can benefit from session-id reuse. */ nsi_set_ssl_session(nsi, (SSL_SESSION *)ssl_session); nsock_log_info(ms, "SSL reconnection requested (IOD #%li) EID %li", nsi->id, nse->id); /* Do the actual connect() */ nse->event_done = 0; nse->status = NSE_STATUS_SUCCESS; nsp_add_event(ms, nse); return nse->id; #endif /* HAVE_OPENSSL */ } /* Request a UDP "connection" to another system (by IP address). The in_addr is * normal network byte order, but the port number should be given in HOST BYTE * ORDER. Since this is UDP, no packets are actually sent. The destination IP * and port are just associated with the nsiod (an actual OS connect() call is * made). You can then use the normal nsock write calls on the socket. There * is no timeout since this call always calls your callback at the next * opportunity. The advantages to having a connected UDP socket (as opposed to * just specifying an address with sendto() are that we can now use a consistent * set of write/read calls for TCP/UDP, received packets from the non-partner * are automatically dropped by the OS, and the OS can provide asynchronous * errors (see Unix Network Programming pp224). ss should be a * sockaddr_storage, sockaddr_in6, or sockaddr_in as appropriate (just like what * you would pass to connect). sslen should be the sizeof the structure you are * passing in. */ nsock_event_id nsock_connect_udp(nsock_pool nsp, nsock_iod nsiod, nsock_ev_handler handler, void *userdata, struct sockaddr *saddr, size_t sslen, unsigned short port) { msiod *nsi = (msiod *)nsiod; mspool *ms = (mspool *)nsp; msevent *nse; struct sockaddr_storage *ss = (struct sockaddr_storage *)saddr; assert(nsi->state == NSIOD_STATE_INITIAL || nsi->state == NSIOD_STATE_UNKNOWN); nse = msevent_new(ms, NSE_TYPE_CONNECT, nsi, -1, handler, userdata); assert(nse); nsock_log_info(ms, "UDP connection requested to %s:%hu (IOD #%li) EID %li", inet_ntop_ez(ss, sslen), port, nsi->id, nse->id); nsock_connect_internal(ms, nse, SOCK_DGRAM, IPPROTO_UDP, ss, sslen, port); nsp_add_event(ms, nse); return nse->id; } /* Returns that host/port/protocol information for the last communication (or * comm. attempt) this nsi has been involved with. By "involved" with I mean * interactions like establishing (or trying to) a connection or sending a UDP * datagram through an unconnected nsock_iod. AF is the address family (AF_INET * or AF_INET6), Protocl is IPPROTO_TCP or IPPROTO_UDP. Pass NULL for * information you do not need. If ANY of the information you requested is not * available, 0 will be returned and the unavailable sockets are zeroed. If * protocol or af is requested but not available, it will be set to -1 (and 0 * returned). The pointers you pass in must be NULL or point to allocated * address space. The sockaddr members should actually be sockaddr_storage, * sockaddr_in6, or sockaddr_in with the socklen of them set appropriately (eg * sizeof(sockaddr_storage) if that is what you are passing). */ int nsi_getlastcommunicationinfo(nsock_iod ms_iod, int *protocol, int *af, struct sockaddr *local, struct sockaddr *remote, size_t socklen) { msiod *nsi = (msiod *)ms_iod; int ret = 1; struct sockaddr_storage sock; socklen_t slen = sizeof(struct sockaddr_storage); int res; assert(socklen > 0); if (nsi->peerlen > 0) { if (remote) memcpy(remote, &(nsi->peer), MIN((unsigned)socklen, nsi->peerlen)); if (protocol) { *protocol = nsi->lastproto; if (*protocol == -1) res = 0; } if (af) { *af = nsi->peer.ss_family; } if (local) { if (nsi->sd >= 0) { res = getsockname(nsi->sd, (struct sockaddr *)&sock, &slen); if (res == -1) { memset(local, 0, socklen); ret = 0; } else { assert(slen > 0); memcpy(local, &sock, MIN((unsigned)slen, socklen)); } } else { memset(local, 0, socklen); ret = 0; } } } else { if (local || remote || protocol || af) ret = 0; if (remote) memset(remote, 0, socklen); if (local) memset(local, 0, socklen); if (protocol) *protocol = -1; if (af) *af = -1; } return ret; }