diff options
Diffstat (limited to 'cpukit/libnetworking/netinet/ip_divert.c')
| -rw-r--r-- | cpukit/libnetworking/netinet/ip_divert.c | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/cpukit/libnetworking/netinet/ip_divert.c b/cpukit/libnetworking/netinet/ip_divert.c new file mode 100644 index 0000000000..6e480989ad --- /dev/null +++ b/cpukit/libnetworking/netinet/ip_divert.c @@ -0,0 +1,385 @@ +/* + * Copyright (c) 1982, 1986, 1988, 1993 + * The Regents of the University of California. 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. + * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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. + * + * $FreeBSD: src/sys/netinet/ip_divert.c,v 1.113 2005/05/13 11:44:37 glebius Exp $ + */ + +/* + * $Id$ + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <sys/param.h> +#include <sys/queue.h> +#include <sys/malloc.h> +#include <sys/mbuf.h> +#include <sys/socket.h> +#include <sys/protosw.h> +#include <sys/socketvar.h> +#include <errno.h> +#include <sys/systm.h> + +#include <net/if.h> +#include <net/route.h> + +#include <netinet/in.h> +#include <netinet/in_systm.h> +#include <netinet/ip.h> +#include <netinet/in_pcb.h> +#include <netinet/in_var.h> +#include <netinet/ip_var.h> + +/* + * Divert sockets + */ + +/* + * Allocate enough space to hold a full IP packet + */ +#define DIVSNDQ (65536 + 100) +#define DIVRCVQ (65536 + 100) + +/* Global variables */ + +/* + * ip_input() and ip_output() set this secret value before calling us to + * let us know which divert port to divert a packet to; this is done so + * we can use the existing prototype for struct protosw's pr_input(). + * This is stored in host order. + */ +u_short ip_divert_port; + +/* + * We set this value to a non-zero port number when we want the call to + * ip_fw_chk() in ip_input() or ip_output() to ignore ``divert <port>'' + * chain entries. This is stored in host order. + */ +u_short ip_divert_ignore; + +/* Internal variables. */ +static struct inpcbhead divcb; +static struct inpcbinfo divcbinfo; + +static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ +static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ + +/* Optimization: have this preinitialized */ +static struct sockaddr_in divsrc = { sizeof(divsrc), AF_INET, 0, { 0 }, { 0 } }; + +/* Internal functions */ + +static int div_output(struct socket *so, + struct mbuf *m, struct mbuf *addr, struct mbuf *control); + +/* + * Initialize divert connection block queue. + */ +void +div_init(void) +{ + LIST_INIT(&divcb); + divcbinfo.listhead = &divcb; + /* + * XXX We don't use the hash list for divert IP, but it's easier + * to allocate a one entry hash list than it is to check all + * over the place for hashbase == NULL. + */ + divcbinfo.hashbase = hashinit(1, M_PCB, &divcbinfo.hashmask); +} + +/* + * Setup generic address and protocol structures + * for div_input routine, then pass them along with + * mbuf chain. ip->ip_len is assumed to have had + * the header length (hlen) subtracted out already. + * We tell whether the packet was incoming or outgoing + * by seeing if hlen == 0, which is a hack. + */ +void +div_input(struct mbuf *m, int hlen) +{ + struct ip *ip; + struct inpcb *inp; + struct socket *sa; + + /* Sanity check */ + if (ip_divert_port == 0) + panic("div_input: port is 0"); + + /* Assure header */ + if (m->m_len < sizeof(struct ip) && + (m = m_pullup(m, sizeof(struct ip))) == 0) { + return; + } + ip = mtod(m, struct ip *); + + /* Record divert port */ + divsrc.sin_port = htons(ip_divert_port); + + /* Restore packet header fields */ + ip->ip_len += hlen; + HTONS(ip->ip_len); + HTONS(ip->ip_off); + + /* Record receive interface address, if any */ + divsrc.sin_addr.s_addr = 0; + if (hlen) { + struct ifaddr *ifa; + +#ifdef DIAGNOSTIC + /* Sanity check */ + if (!(m->m_flags & M_PKTHDR)) + panic("div_input: no pkt hdr"); +#endif + + /* More fields affected by ip_input() */ + HTONS(ip->ip_id); + + /* Find IP address for recieve interface */ + for (ifa = m->m_pkthdr.rcvif->if_addrlist; + ifa != NULL; ifa = ifa->ifa_next) { + if (ifa->ifa_addr == NULL) + continue; + if (ifa->ifa_addr->sa_family != AF_INET) + continue; + divsrc.sin_addr = + ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; + break; + } + } + + /* Put packet on socket queue, if any */ + sa = NULL; + for (inp = divcb.lh_first; inp != NULL; inp = inp->inp_list.le_next) { + if (inp->inp_lport == htons(ip_divert_port)) + sa = inp->inp_socket; + } + if (sa) { + if (sbappendaddr(&sa->so_rcv, (struct sockaddr *)&divsrc, + m, (struct mbuf *)0) == 0) + m_freem(m); + else + sorwakeup(sa); + } else { + m_freem(m); + ipstat.ips_noproto++; + ipstat.ips_delivered--; + } +} + +/* + * Deliver packet back into the IP processing machinery. + * + * If no address specified, or address is 0.0.0.0, send to ip_output(); + * otherwise, send to ip_input() and mark as having been received on + * the interface with that address. + * + * If no address specified, or dest port is 0, allow packet to divert + * back to this socket; otherwise, don't. + */ +static int +div_output(struct socket *so, struct mbuf *m, + struct mbuf *addr, struct mbuf *control) +{ + register struct inpcb *const inp = sotoinpcb(so); + register struct ip *const ip = mtod(m, struct ip *); + struct sockaddr_in *sin = NULL; + int error = 0; + + if (control) + m_freem(control); /* XXX */ + if (addr) + sin = mtod(addr, struct sockaddr_in *); + + /* Loopback avoidance option */ + ip_divert_ignore = ntohs(inp->inp_lport); + + /* Reinject packet into the system as incoming or outgoing */ + if (!sin || sin->sin_addr.s_addr == 0) { + /* Don't allow both user specified and setsockopt options, + and don't allow packet length sizes that will crash */ + if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options) || + ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) { + error = EINVAL; + goto cantsend; + } + + /* Convert fields to host order for ip_output() */ + NTOHS(ip->ip_len); + NTOHS(ip->ip_off); + + /* Send packet to output processing */ + ipstat.ips_rawout++; /* XXX */ + error = ip_output(m, inp->inp_options, &inp->inp_route, + (so->so_options & SO_DONTROUTE) | + IP_ALLOWBROADCAST | IP_RAWOUTPUT, inp->inp_moptions); + } else { + struct ifaddr *ifa; + + /* Find receive interface with the given IP address */ + sin->sin_port = 0; + if ((ifa = ifa_ifwithaddr((struct sockaddr *) sin)) == 0) { + error = EADDRNOTAVAIL; + goto cantsend; + } + m->m_pkthdr.rcvif = ifa->ifa_ifp; + + /* Send packet to input processing */ + ip_input(m); + } + + /* Reset for next time (and other packets) */ + ip_divert_ignore = 0; + return error; + +cantsend: + ip_divert_ignore = 0; + m_freem(m); + return error; +} + +/*ARGSUSED*/ +int +div_usrreq( + struct socket *so, + int req, + struct mbuf *m, + struct mbuf *nam, + struct mbuf *control ) +{ + register int error = 0; + register struct inpcb *inp = sotoinpcb(so); + int s; + + if (inp == NULL && req != PRU_ATTACH) { + error = EINVAL; + goto release; + } + switch (req) { + + case PRU_ATTACH: + if (inp) + panic("div_attach"); + if ((so->so_state & SS_PRIV) == 0) { + error = EACCES; + break; + } + s = splnet(); + error = in_pcballoc(so, &divcbinfo); + splx(s); + if (error) + break; + error = soreserve(so, div_sendspace, div_recvspace); + if (error) + break; + inp = (struct inpcb *)so->so_pcb; + inp->inp_ip_p = (intptr_t)nam; /* XXX */ + inp->inp_flags |= INP_HDRINCL; + /* The socket is always "connected" because + we always know "where" to send the packet */ + so->so_state |= SS_ISCONNECTED; + break; + + case PRU_DISCONNECT: + if ((so->so_state & SS_ISCONNECTED) == 0) { + error = ENOTCONN; + break; + } + /* FALLTHROUGH */ + case PRU_ABORT: + soisdisconnected(so); + /* FALLTHROUGH */ + case PRU_DETACH: + if (inp == 0) + panic("div_detach"); + in_pcbdetach(inp); + break; + + case PRU_BIND: + s = splnet(); + error = in_pcbbind(inp, nam); + splx(s); + break; + + /* + * Mark the connection as being incapable of further input. + */ + case PRU_SHUTDOWN: + socantsendmore(so); + break; + + case PRU_SEND: + /* Packet must have a header (but that's about it) */ + if (m->m_len < sizeof (struct ip) || + (m = m_pullup(m, sizeof (struct ip))) == 0) { + ipstat.ips_toosmall++; + error = EINVAL; + break; + } + + /* Send packet */ + error = div_output(so, m, nam, control); + m = NULL; + break; + + case PRU_SOCKADDR: + in_setsockaddr(inp, nam); + break; + + case PRU_SENSE: + /* + * stat: don't bother with a blocksize. + */ + return (0); + + /* + * Not supported. + */ + case PRU_CONNECT: + case PRU_CONNECT2: + case PRU_CONTROL: + case PRU_RCVOOB: + case PRU_RCVD: + case PRU_LISTEN: + case PRU_ACCEPT: + case PRU_SENDOOB: + case PRU_PEERADDR: + error = EOPNOTSUPP; + break; + + default: + panic("div_usrreq"); + } +release: + if (m) + m_freem(m); + return (error); +} |