| /* |
| * Copyright (C) 1997-2003 by Darren Reed. |
| * |
| * See the IPFILTER.LICENCE file for details on licencing. |
| */ |
| #if defined(KERNEL) || defined(_KERNEL) |
| # undef KERNEL |
| # undef _KERNEL |
| # define KERNEL 1 |
| # define _KERNEL 1 |
| #endif |
| #include <sys/errno.h> |
| #include <sys/types.h> |
| #include <sys/param.h> |
| #include <sys/time.h> |
| #include <sys/file.h> |
| #if !defined(AIX) |
| # include <sys/fcntl.h> |
| #endif |
| #if !defined(_KERNEL) && !defined(__KERNEL__) |
| # include <stdio.h> |
| # include <string.h> |
| # include <stdlib.h> |
| # include <ctype.h> |
| # define _KERNEL |
| # ifdef __OpenBSD__ |
| struct file; |
| # endif |
| # include <sys/uio.h> |
| # undef _KERNEL |
| #endif |
| #if !defined(linux) |
| # include <sys/protosw.h> |
| #endif |
| #include <sys/socket.h> |
| #if defined(_KERNEL) |
| # if !defined(__NetBSD__) && !defined(sun) && !defined(__osf__) && \ |
| !defined(__OpenBSD__) && !defined(__hpux) && !defined(__sgi) && \ |
| !defined(AIX) |
| # include <sys/ctype.h> |
| # endif |
| # include <sys/systm.h> |
| # if !defined(__SVR4) && !defined(__svr4__) |
| # include <sys/mbuf.h> |
| # endif |
| #endif |
| #if defined(_KERNEL) && (__FreeBSD_version >= 220000) |
| # include <sys/filio.h> |
| # include <sys/fcntl.h> |
| #else |
| # include <sys/ioctl.h> |
| #endif |
| #if defined(__SVR4) || defined(__svr4__) |
| # include <sys/byteorder.h> |
| # ifdef _KERNEL |
| # include <sys/dditypes.h> |
| # endif |
| # include <sys/stream.h> |
| # include <sys/kmem.h> |
| #endif |
| #if __FreeBSD__ > 2 |
| # include <sys/queue.h> |
| #endif |
| #include <net/if.h> |
| #ifdef sun |
| # include <net/af.h> |
| #endif |
| #include <net/route.h> |
| #include <netinet/in.h> |
| #include <netinet/in_systm.h> |
| #include <netinet/ip.h> |
| #ifndef linux |
| # include <netinet/ip_var.h> |
| #endif |
| #include <netinet/tcp.h> |
| #include <netinet/udp.h> |
| #include <netinet/ip_icmp.h> |
| #include "netinet/ip_compat.h" |
| #include <netinet/tcpip.h> |
| #include "netinet/ip_fil.h" |
| #include "netinet/ip_nat.h" |
| #include "netinet/ip_state.h" |
| #include "netinet/ip_proxy.h" |
| #if (__FreeBSD_version >= 300000) |
| # include <sys/malloc.h> |
| #endif |
| |
| #include "netinet/ip_ftp_pxy.c" |
| #include "netinet/ip_rcmd_pxy.c" |
| # include "netinet/ip_pptp_pxy.c" |
| #if defined(_KERNEL) |
| # include "netinet/ip_irc_pxy.c" |
| # include "netinet/ip_raudio_pxy.c" |
| # include "netinet/ip_h323_pxy.c" |
| # include "netinet/ip_netbios_pxy.c" |
| #endif |
| #include "netinet/ip_ipsec_pxy.c" |
| #include "netinet/ip_rpcb_pxy.c" |
| |
| /* END OF INCLUDES */ |
| |
| #if !defined(lint) |
| static const char rcsid[] = "@(#)$Id$"; |
| #endif |
| |
| static int appr_fixseqack __P((fr_info_t *, ip_t *, ap_session_t *, int )); |
| |
| #define AP_SESS_SIZE 53 |
| |
| #if defined(_KERNEL) |
| int ipf_proxy_debug = 0; |
| #else |
| int ipf_proxy_debug = 2; |
| #endif |
| ap_session_t *ap_sess_tab[AP_SESS_SIZE]; |
| ap_session_t *ap_sess_list = NULL; |
| aproxy_t *ap_proxylist = NULL; |
| aproxy_t ap_proxies[] = { |
| #ifdef IPF_FTP_PROXY |
| { NULL, "ftp", (char)IPPROTO_TCP, 0, 0, ippr_ftp_init, ippr_ftp_fini, |
| ippr_ftp_new, ippr_ftp_del, ippr_ftp_in, ippr_ftp_out, NULL, |
| NULL, NULL }, |
| #endif |
| #ifdef IPF_IRC_PROXY |
| { NULL, "irc", (char)IPPROTO_TCP, 0, 0, ippr_irc_init, ippr_irc_fini, |
| ippr_irc_new, NULL, NULL, ippr_irc_out, NULL, NULL, NULL, NULL }, |
| #endif |
| #ifdef IPF_RCMD_PROXY |
| { NULL, "rcmd", (char)IPPROTO_TCP, 0, 0, ippr_rcmd_init, ippr_rcmd_fini, |
| ippr_rcmd_new, NULL, ippr_rcmd_in, ippr_rcmd_out, NULL, NULL, |
| NULL, NULL }, |
| #endif |
| #ifdef IPF_RAUDIO_PROXY |
| { NULL, "raudio", (char)IPPROTO_TCP, 0, 0, ippr_raudio_init, ippr_raudio_fini, |
| ippr_raudio_new, NULL, ippr_raudio_in, ippr_raudio_out, NULL, NULL, |
| NULL, NULL }, |
| #endif |
| #ifdef IPF_MSNRPC_PROXY |
| { NULL, "msnrpc", (char)IPPROTO_TCP, 0, 0, ippr_msnrpc_init, ippr_msnrpc_fini, |
| ippr_msnrpc_new, NULL, ippr_msnrpc_in, ippr_msnrpc_out, NULL, NULL, |
| NULL, NULL }, |
| #endif |
| #ifdef IPF_NETBIOS_PROXY |
| { NULL, "netbios", (char)IPPROTO_UDP, 0, 0, ippr_netbios_init, ippr_netbios_fini, |
| NULL, NULL, NULL, ippr_netbios_out, NULL, NULL, NULL, NULL }, |
| #endif |
| #ifdef IPF_IPSEC_PROXY |
| { NULL, "ipsec", (char)IPPROTO_UDP, 0, 0, |
| ippr_ipsec_init, ippr_ipsec_fini, ippr_ipsec_new, ippr_ipsec_del, |
| ippr_ipsec_inout, ippr_ipsec_inout, ippr_ipsec_match, NULL, |
| NULL, NULL }, |
| #endif |
| #ifdef IPF_DNS_PROXY |
| { NULL, "dns", (char)IPPROTO_UDP, 0, 0, |
| ippr_dns_init, ippr_dns_fini, ippr_dns_new, ippr_ipsec_del, |
| ippr_dns_inout, ippr_dns_inout, ippr_dns_match, NULL, |
| NULL, NULL }, |
| #endif |
| #ifdef IPF_PPTP_PROXY |
| { NULL, "pptp", (char)IPPROTO_TCP, 0, 0, |
| ippr_pptp_init, ippr_pptp_fini, ippr_pptp_new, ippr_pptp_del, |
| ippr_pptp_inout, ippr_pptp_inout, NULL, NULL, NULL, NULL }, |
| #endif |
| #ifdef IPF_H323_PROXY |
| { NULL, "h323", (char)IPPROTO_TCP, 0, 0, ippr_h323_init, ippr_h323_fini, |
| ippr_h323_new, ippr_h323_del, ippr_h323_in, NULL, NULL, NULL, NULL }, |
| { NULL, "h245", (char)IPPROTO_TCP, 0, 0, NULL, NULL, |
| ippr_h245_new, NULL, NULL, ippr_h245_out, NULL, NULL, NULL }, |
| #endif |
| #ifdef IPF_RPCB_PROXY |
| # ifndef _KERNEL |
| { NULL, "rpcbt", (char)IPPROTO_TCP, 0, 0, |
| ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del, |
| ippr_rpcb_in, ippr_rpcb_out, NULL, NULL, NULL, NULL }, |
| # endif |
| { NULL, "rpcbu", (char)IPPROTO_UDP, 0, 0, |
| ippr_rpcb_init, ippr_rpcb_fini, ippr_rpcb_new, ippr_rpcb_del, |
| ippr_rpcb_in, ippr_rpcb_out, NULL, NULL, NULL, NULL }, |
| #endif |
| { NULL, "", '\0', 0, 0, NULL, NULL, NULL, NULL, NULL, NULL } |
| }; |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_add */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: ap(I) - pointer to proxy structure */ |
| /* */ |
| /* Dynamically add a new kernel proxy. Ensure that it is unique in the */ |
| /* collection compiled in and dynamically added. */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_add(ap) |
| aproxy_t *ap; |
| { |
| aproxy_t *a; |
| |
| for (a = ap_proxies; a->apr_p; a++) |
| if ((a->apr_p == ap->apr_p) && |
| !strncmp(a->apr_label, ap->apr_label, |
| sizeof(ap->apr_label))) { |
| if (ipf_proxy_debug > 1) |
| printf("appr_add: %s/%d already present (B)\n", |
| a->apr_label, a->apr_p); |
| return -1; |
| } |
| |
| for (a = ap_proxylist; (a != NULL); a = a->apr_next) |
| if ((a->apr_p == ap->apr_p) && |
| !strncmp(a->apr_label, ap->apr_label, |
| sizeof(ap->apr_label))) { |
| if (ipf_proxy_debug > 1) |
| printf("appr_add: %s/%d already present (D)\n", |
| a->apr_label, a->apr_p); |
| return -1; |
| } |
| ap->apr_next = ap_proxylist; |
| ap_proxylist = ap; |
| if (ap->apr_init != NULL) |
| return (*ap->apr_init)(); |
| return 0; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_ctl */ |
| /* Returns: int - 0 == success, else error */ |
| /* Parameters: ctl(I) - pointer to proxy control structure */ |
| /* */ |
| /* Check to see if the proxy this control request has come through for */ |
| /* exists, and if it does and it has a control function then invoke that */ |
| /* control function. */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_ctl(ctl) |
| ap_ctl_t *ctl; |
| { |
| aproxy_t *a; |
| int error; |
| |
| a = appr_lookup(ctl->apc_p, ctl->apc_label); |
| if (a == NULL) { |
| if (ipf_proxy_debug > 1) |
| printf("appr_ctl: can't find %s/%d\n", |
| ctl->apc_label, ctl->apc_p); |
| ipf_interror = 80001; |
| error = ESRCH; |
| } else if (a->apr_ctl == NULL) { |
| if (ipf_proxy_debug > 1) |
| printf("appr_ctl: no ctl function for %s/%d\n", |
| ctl->apc_label, ctl->apc_p); |
| ipf_interror = 80002; |
| error = ENXIO; |
| } else { |
| error = (*a->apr_ctl)(a, ctl); |
| if ((error != 0) && (ipf_proxy_debug > 1)) |
| printf("appr_ctl: %s/%d ctl error %d\n", |
| a->apr_label, a->apr_p, error); |
| } |
| return error; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_del */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: ap(I) - pointer to proxy structure */ |
| /* */ |
| /* Delete a proxy that has been added dynamically from those available. */ |
| /* If it is in use, return 1 (do not destroy NOW), not in use 0 or -1 */ |
| /* if it cannot be matched. */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_del(ap) |
| aproxy_t *ap; |
| { |
| aproxy_t *a, **app; |
| |
| for (app = &ap_proxylist; ((a = *app) != NULL); app = &a->apr_next) |
| if (a == ap) { |
| a->apr_flags |= APR_DELETE; |
| *app = a->apr_next; |
| if (ap->apr_ref != 0) { |
| if (ipf_proxy_debug > 2) |
| printf("appr_del: orphaning %s/%d\n", |
| ap->apr_label, ap->apr_p); |
| return 1; |
| } |
| return 0; |
| } |
| if (ipf_proxy_debug > 1) |
| printf("appr_del: proxy %lx not found\n", (u_long)ap); |
| return -1; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_ok */ |
| /* Returns: int - 1 == good match else not. */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_ok(fin, tcp, nat) |
| fr_info_t *fin; |
| tcphdr_t *tcp; |
| ipnat_t *nat; |
| { |
| aproxy_t *apr = nat->in_apr; |
| u_short dport = nat->in_odport; |
| |
| if ((apr == NULL) || (apr->apr_flags & APR_DELETE) || |
| (fin->fin_p != apr->apr_p)) |
| return 0; |
| if ((tcp == NULL) && dport) |
| return 0; |
| return 1; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_ioctl */ |
| /* Returns: int - 0 == success, else error */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_ioctl(data, cmd, mode, ctx) |
| caddr_t data; |
| ioctlcmd_t cmd; |
| int mode; |
| void *ctx; |
| { |
| ap_ctl_t ctl; |
| caddr_t ptr; |
| int error; |
| |
| mode = mode; /* LINT */ |
| |
| switch (cmd) |
| { |
| case SIOCPROXY : |
| error = ipf_inobj(data, &ctl, IPFOBJ_PROXYCTL); |
| if (error != 0) { |
| return error; |
| } |
| ptr = NULL; |
| |
| if (ctl.apc_dsize > 0) { |
| KMALLOCS(ptr, caddr_t, ctl.apc_dsize); |
| if (ptr == NULL) { |
| ipf_interror = 80003; |
| error = ENOMEM; |
| } else { |
| error = copyinptr(ctl.apc_data, ptr, |
| ctl.apc_dsize); |
| if (error == 0) |
| ctl.apc_data = ptr; |
| } |
| } else { |
| ctl.apc_data = NULL; |
| error = 0; |
| } |
| |
| if (error == 0) |
| error = appr_ctl(&ctl); |
| |
| if ((error != 0) && (ptr != NULL)) { |
| KFREES(ptr, ctl.apc_dsize); |
| } |
| break; |
| |
| default : |
| ipf_interror = 80004; |
| error = EINVAL; |
| } |
| return error; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_match */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* If a proxy has a match function, call that to do extended packet */ |
| /* matching. */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_match(fin, nat) |
| fr_info_t *fin; |
| nat_t *nat; |
| { |
| aproxy_t *apr; |
| ipnat_t *ipn; |
| int result; |
| |
| ipn = nat->nat_ptr; |
| if (ipf_proxy_debug > 8) |
| printf("appr_match(%lx,%lx) aps %lx ptr %lx\n", |
| (u_long)fin, (u_long)nat, (u_long)nat->nat_aps, |
| (u_long)ipn); |
| |
| if ((fin->fin_flx & (FI_SHORT|FI_BAD)) != 0) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_match: flx 0x%x (BAD|SHORT)\n", |
| fin->fin_flx); |
| return -1; |
| } |
| |
| apr = ipn->in_apr; |
| if ((apr == NULL) || (apr->apr_flags & APR_DELETE)) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_match:apr %lx apr_flags 0x%x\n", |
| (u_long)apr, apr ? apr->apr_flags : 0); |
| return -1; |
| } |
| |
| if (apr->apr_match != NULL) { |
| result = (*apr->apr_match)(fin, nat->nat_aps, nat); |
| if (result != 0) { |
| if (ipf_proxy_debug > 4) |
| printf("appr_match: result %d\n", result); |
| return -1; |
| } |
| } |
| return 0; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_new */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* Allocate a new application proxy structure and fill it in with the */ |
| /* relevant details. call the init function once complete, prior to */ |
| /* returning. */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_new(fin, nat) |
| fr_info_t *fin; |
| nat_t *nat; |
| { |
| register ap_session_t *aps; |
| aproxy_t *apr; |
| |
| if (ipf_proxy_debug > 8) |
| printf("appr_new(%lx,%lx) \n", (u_long)fin, (u_long)nat); |
| |
| if ((nat->nat_ptr == NULL) || (nat->nat_aps != NULL)) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_new: nat_ptr %lx nat_aps %lx\n", |
| (u_long)nat->nat_ptr, (u_long)nat->nat_aps); |
| return -1; |
| } |
| |
| apr = nat->nat_ptr->in_apr; |
| |
| if ((apr->apr_flags & APR_DELETE) || |
| (fin->fin_p != apr->apr_p)) { |
| if (ipf_proxy_debug > 2) |
| printf("appr_new: apr_flags 0x%x p %d/%d\n", |
| apr->apr_flags, fin->fin_p, apr->apr_p); |
| return -1; |
| } |
| |
| KMALLOC(aps, ap_session_t *); |
| if (!aps) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_new: malloc failed (%lu)\n", |
| (u_long)sizeof(ap_session_t)); |
| return -1; |
| } |
| |
| bzero((char *)aps, sizeof(*aps)); |
| aps->aps_p = fin->fin_p; |
| aps->aps_data = NULL; |
| aps->aps_apr = apr; |
| aps->aps_psiz = 0; |
| if (apr->apr_new != NULL) |
| if ((*apr->apr_new)(fin, aps, nat) == -1) { |
| if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) { |
| KFREES(aps->aps_data, aps->aps_psiz); |
| } |
| KFREE(aps); |
| if (ipf_proxy_debug > 2) |
| printf("appr_new: new(%lx) failed\n", |
| (u_long)apr->apr_new); |
| return -1; |
| } |
| aps->aps_nat = nat; |
| aps->aps_next = ap_sess_list; |
| ap_sess_list = aps; |
| nat->nat_aps = aps; |
| |
| return 0; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_check */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* Check to see if a packet should be passed through an active proxy */ |
| /* routine if one has been setup for it. We don't need to check the */ |
| /* checksum here if IPFILTER_CKSUM is defined because if it is, a failed */ |
| /* check causes FI_BAD to be set. */ |
| /* ------------------------------------------------------------------------ */ |
| int |
| appr_check(fin, nat) |
| fr_info_t *fin; |
| nat_t *nat; |
| { |
| #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) |
| # if defined(ICK_VALID) |
| mb_t *m; |
| # endif |
| int dosum = 1; |
| #endif |
| tcphdr_t *tcp = NULL; |
| udphdr_t *udp = NULL; |
| ap_session_t *aps; |
| aproxy_t *apr; |
| ip_t *ip; |
| short rv; |
| int err; |
| #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) |
| u_32_t s1, s2, sd; |
| #endif |
| |
| if (fin->fin_flx & FI_BAD) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_check: flx 0x%x (BAD)\n", fin->fin_flx); |
| return -1; |
| } |
| |
| #ifndef IPFILTER_CKSUM |
| if ((fin->fin_out == 0) && (ipf_checkl4sum(fin) == -1)) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_check: l4 checksum failure %d\n", |
| fin->fin_p); |
| if (fin->fin_p == IPPROTO_TCP) |
| ipf_stats[fin->fin_out].fr_tcpbad++; |
| return -1; |
| } |
| #endif |
| |
| aps = nat->nat_aps; |
| if ((aps != NULL) && (aps->aps_p == fin->fin_p)) { |
| /* |
| * If there is data in this packet to be proxied then try and |
| * get it all into the one buffer, else drop it. |
| */ |
| #if defined(MENTAT) || defined(HAVE_M_PULLDOWN) |
| if ((fin->fin_dlen > 0) && !(fin->fin_flx & FI_COALESCE)) |
| if (ipf_coalesce(fin) == -1) { |
| if (ipf_proxy_debug > 0) |
| printf("appr_check: coalesce failed %x\n", fin->fin_flx); |
| return -1; |
| } |
| #endif |
| ip = fin->fin_ip; |
| |
| switch (fin->fin_p) |
| { |
| case IPPROTO_TCP : |
| tcp = (tcphdr_t *)fin->fin_dp; |
| |
| #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_VALID) |
| m = fin->fin_qfm; |
| if (dohwcksum && (m->b_ick_flag == ICK_VALID)) |
| dosum = 0; |
| #endif |
| /* |
| * Don't bother the proxy with these...or in fact, |
| * should we free up proxy stuff when seen? |
| */ |
| if ((fin->fin_tcpf & TH_RST) != 0) |
| break; |
| /*FALLTHROUGH*/ |
| case IPPROTO_UDP : |
| udp = (udphdr_t *)fin->fin_dp; |
| break; |
| default : |
| break; |
| } |
| |
| apr = aps->aps_apr; |
| err = 0; |
| if (fin->fin_out != 0) { |
| if (apr->apr_outpkt != NULL) |
| err = (*apr->apr_outpkt)(fin, aps, nat); |
| } else { |
| if (apr->apr_inpkt != NULL) |
| err = (*apr->apr_inpkt)(fin, aps, nat); |
| } |
| |
| rv = APR_EXIT(err); |
| if (((ipf_proxy_debug > 0) && (rv != 0)) || |
| (ipf_proxy_debug > 8)) |
| printf("appr_check: out %d err %x rv %d\n", |
| fin->fin_out, err, rv); |
| if (rv == 1) |
| return -1; |
| |
| if (rv == 2) { |
| appr_free(apr); |
| nat->nat_aps = NULL; |
| return -1; |
| } |
| |
| /* |
| * If err != 0 then the data size of the packet has changed |
| * so we need to recalculate the header checksums for the |
| * packet. |
| */ |
| #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) |
| if (err != 0) { |
| short adjlen = err & 0xffff; |
| |
| s1 = LONG_SUM(fin->fin_plen - adjlen); |
| s2 = LONG_SUM(fin->fin_plen); |
| CALC_SUMD(s1, s2, sd); |
| ipf_fix_outcksum(fin, &ip->ip_sum, sd); |
| } |
| #endif |
| |
| /* |
| * For TCP packets, we may need to adjust the sequence and |
| * acknowledgement numbers to reflect changes in size of the |
| * data stream. |
| * |
| * For both TCP and UDP, recalculate the layer 4 checksum, |
| * regardless, as we can't tell (here) if data has been |
| * changed or not. |
| */ |
| if (tcp != NULL) { |
| err = appr_fixseqack(fin, ip, aps, APR_INC(err)); |
| #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) |
| if (dosum) |
| tcp->th_sum = fr_cksum(fin->fin_qfm, ip, |
| IPPROTO_TCP, tcp, |
| fin->fin_plen); |
| #else |
| tcp->th_sum = fr_cksum(fin->fin_m, ip, |
| IPPROTO_TCP, tcp, |
| fin->fin_plen); |
| #endif |
| } else if ((udp != NULL) && (udp->uh_sum != 0)) { |
| #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) |
| if (dosum) |
| udp->uh_sum = fr_cksum(fin->fin_qfm, ip, |
| IPPROTO_UDP, udp, |
| fin->fin_plen); |
| #else |
| udp->uh_sum = fr_cksum(fin->fin_m, ip, |
| IPPROTO_UDP, udp, |
| fin->fin_plen); |
| #endif |
| } |
| aps->aps_bytes += fin->fin_plen; |
| aps->aps_pkts++; |
| return 1; |
| } |
| return 0; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_lookup */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* Search for an proxy by the protocol it is being used with and its name. */ |
| /* ------------------------------------------------------------------------ */ |
| aproxy_t * |
| appr_lookup(pr, name) |
| u_int pr; |
| char *name; |
| { |
| aproxy_t *ap; |
| |
| if (ipf_proxy_debug > 8) |
| printf("appr_lookup(%d,%s)\n", pr, name); |
| |
| for (ap = ap_proxies; ap->apr_p; ap++) |
| if ((ap->apr_p == pr) && |
| !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { |
| ap->apr_ref++; |
| return ap; |
| } |
| |
| for (ap = ap_proxylist; ap; ap = ap->apr_next) |
| if ((ap->apr_p == pr) && |
| !strncmp(name, ap->apr_label, sizeof(ap->apr_label))) { |
| ap->apr_ref++; |
| return ap; |
| } |
| if (ipf_proxy_debug > 2) |
| printf("appr_lookup: failed for %d/%s\n", pr, name); |
| return NULL; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_free */ |
| /* Returns: Nil */ |
| /* Parameters: ap(I) - pointer to proxy structure */ |
| /* */ |
| /* ------------------------------------------------------------------------ */ |
| void |
| appr_free(ap) |
| aproxy_t *ap; |
| { |
| ap->apr_ref--; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: aps_free */ |
| /* Returns: Nil */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* Locks Held: ipf_nat_new, ipf_nat(W) */ |
| /* ------------------------------------------------------------------------ */ |
| void |
| aps_free(aps) |
| ap_session_t *aps; |
| { |
| ap_session_t *a, **ap; |
| aproxy_t *apr; |
| |
| if (!aps) |
| return; |
| |
| for (ap = &ap_sess_list; ((a = *ap) != NULL); ap = &a->aps_next) |
| if (a == aps) { |
| *ap = a->aps_next; |
| break; |
| } |
| |
| apr = aps->aps_apr; |
| if ((apr != NULL) && (apr->apr_del != NULL)) |
| (*apr->apr_del)(aps); |
| |
| if ((aps->aps_data != NULL) && (aps->aps_psiz != 0)) |
| KFREES(aps->aps_data, aps->aps_psiz); |
| KFREE(aps); |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_fixseqack */ |
| /* Returns: int - 2 if TCP ack/seq is changed, else 0 */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* ------------------------------------------------------------------------ */ |
| static int |
| appr_fixseqack(fin, ip, aps, inc) |
| fr_info_t *fin; |
| ip_t *ip; |
| ap_session_t *aps; |
| int inc; |
| { |
| int sel, ch = 0, out, nlen; |
| u_32_t seq1, seq2; |
| tcphdr_t *tcp; |
| short inc2; |
| |
| tcp = (tcphdr_t *)fin->fin_dp; |
| out = fin->fin_out; |
| /* |
| * ip_len has already been adjusted by 'inc'. |
| */ |
| nlen = fin->fin_plen; |
| nlen -= (IP_HL(ip) << 2) + (TCP_OFF(tcp) << 2); |
| |
| inc2 = inc; |
| inc = (int)inc2; |
| |
| if (out != 0) { |
| seq1 = (u_32_t)ntohl(tcp->th_seq); |
| sel = aps->aps_sel[out]; |
| |
| /* switch to other set ? */ |
| if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && |
| (seq1 > aps->aps_seqmin[!sel])) { |
| if (ipf_proxy_debug > 7) |
| printf("proxy out switch set seq %d -> %d %x > %x\n", |
| sel, !sel, seq1, |
| aps->aps_seqmin[!sel]); |
| sel = aps->aps_sel[out] = !sel; |
| } |
| |
| if (aps->aps_seqoff[sel]) { |
| seq2 = aps->aps_seqmin[sel] - aps->aps_seqoff[sel]; |
| if (seq1 > seq2) { |
| seq2 = aps->aps_seqoff[sel]; |
| seq1 += seq2; |
| tcp->th_seq = htonl(seq1); |
| ch = 1; |
| } |
| } |
| |
| if (inc && (seq1 > aps->aps_seqmin[!sel])) { |
| aps->aps_seqmin[sel] = seq1 + nlen - 1; |
| aps->aps_seqoff[sel] = aps->aps_seqoff[sel] + inc; |
| if (ipf_proxy_debug > 7) |
| printf("proxy seq set %d at %x to %d + %d\n", |
| sel, aps->aps_seqmin[sel], |
| aps->aps_seqoff[sel], inc); |
| } |
| |
| /***/ |
| |
| seq1 = ntohl(tcp->th_ack); |
| sel = aps->aps_sel[1 - out]; |
| |
| /* switch to other set ? */ |
| if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && |
| (seq1 > aps->aps_ackmin[!sel])) { |
| if (ipf_proxy_debug > 7) |
| printf("proxy out switch set ack %d -> %d %x > %x\n", |
| sel, !sel, seq1, |
| aps->aps_ackmin[!sel]); |
| sel = aps->aps_sel[1 - out] = !sel; |
| } |
| |
| if (aps->aps_ackoff[sel] && (seq1 > aps->aps_ackmin[sel])) { |
| seq2 = aps->aps_ackoff[sel]; |
| tcp->th_ack = htonl(seq1 - seq2); |
| ch = 1; |
| } |
| } else { |
| seq1 = ntohl(tcp->th_seq); |
| sel = aps->aps_sel[out]; |
| |
| /* switch to other set ? */ |
| if ((aps->aps_ackmin[!sel] > aps->aps_ackmin[sel]) && |
| (seq1 > aps->aps_ackmin[!sel])) { |
| if (ipf_proxy_debug > 7) |
| printf("proxy in switch set ack %d -> %d %x > %x\n", |
| sel, !sel, seq1, aps->aps_ackmin[!sel]); |
| sel = aps->aps_sel[out] = !sel; |
| } |
| |
| if (aps->aps_ackoff[sel]) { |
| seq2 = aps->aps_ackmin[sel] - aps->aps_ackoff[sel]; |
| if (seq1 > seq2) { |
| seq2 = aps->aps_ackoff[sel]; |
| seq1 += seq2; |
| tcp->th_seq = htonl(seq1); |
| ch = 1; |
| } |
| } |
| |
| if (inc && (seq1 > aps->aps_ackmin[!sel])) { |
| aps->aps_ackmin[!sel] = seq1 + nlen - 1; |
| aps->aps_ackoff[!sel] = aps->aps_ackoff[sel] + inc; |
| |
| if (ipf_proxy_debug > 7) |
| printf("proxy ack set %d at %x to %d + %d\n", |
| !sel, aps->aps_seqmin[!sel], |
| aps->aps_seqoff[sel], inc); |
| } |
| |
| /***/ |
| |
| seq1 = ntohl(tcp->th_ack); |
| sel = aps->aps_sel[1 - out]; |
| |
| /* switch to other set ? */ |
| if ((aps->aps_seqmin[!sel] > aps->aps_seqmin[sel]) && |
| (seq1 > aps->aps_seqmin[!sel])) { |
| if (ipf_proxy_debug > 7) |
| printf("proxy in switch set seq %d -> %d %x > %x\n", |
| sel, !sel, seq1, aps->aps_seqmin[!sel]); |
| sel = aps->aps_sel[1 - out] = !sel; |
| } |
| |
| if (aps->aps_seqoff[sel] != 0) { |
| if (ipf_proxy_debug > 7) |
| printf("sel %d seqoff %d seq1 %x seqmin %x\n", |
| sel, aps->aps_seqoff[sel], seq1, |
| aps->aps_seqmin[sel]); |
| if (seq1 > aps->aps_seqmin[sel]) { |
| seq2 = aps->aps_seqoff[sel]; |
| tcp->th_ack = htonl(seq1 - seq2); |
| ch = 1; |
| } |
| } |
| } |
| |
| if (ipf_proxy_debug > 8) |
| printf("appr_fixseqack: seq %x ack %x\n", |
| (u_32_t)ntohl(tcp->th_seq), (u_32_t)ntohl(tcp->th_ack)); |
| return ch ? 2 : 0; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_init */ |
| /* Returns: int - -1 == error, 0 == success */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* ------------------------------------------------------------------------ */ |
| /* |
| * Initialise hook for kernel application proxies. |
| * Call the initialise routine for all the compiled in kernel proxies. |
| */ |
| int |
| appr_init() |
| { |
| aproxy_t *ap; |
| int err = 0; |
| |
| for (ap = ap_proxies; ap->apr_p; ap++) { |
| if (ap->apr_init != NULL) { |
| err = (*ap->apr_init)(); |
| if (err != 0) |
| break; |
| } |
| } |
| return err; |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_unload */ |
| /* Returns: Nil */ |
| /* Parameters: Nil */ |
| /* */ |
| /* Unload hook for kernel application proxies. */ |
| /* Call the finialise routine for all the compiled in kernel proxies. */ |
| /* ------------------------------------------------------------------------ */ |
| void |
| appr_unload() |
| { |
| aproxy_t *ap; |
| |
| for (ap = ap_proxies; ap->apr_p; ap++) |
| if (ap->apr_fini != NULL) |
| (*ap->apr_fini)(); |
| for (ap = ap_proxylist; ap; ap = ap->apr_next) |
| if (ap->apr_fini != NULL) |
| (*ap->apr_fini)(); |
| } |
| |
| |
| /* ------------------------------------------------------------------------ */ |
| /* Function: appr_flush */ |
| /* Returns: Nil */ |
| /* Parameters: fin(I) - pointer to packet information */ |
| /* nat(I) - pointer to current NAT session */ |
| /* */ |
| /* ------------------------------------------------------------------------ */ |
| void |
| appr_flush(how) |
| int how; |
| { |
| aproxy_t *ap; |
| |
| switch (how) |
| { |
| case 0 : |
| for (ap = ap_proxies; ap->apr_p; ap++) |
| if (ap->apr_flush != NULL) |
| (*ap->apr_flush)(ap, how); |
| for (ap = ap_proxylist; ap; ap = ap->apr_next) |
| if (ap->apr_flush != NULL) |
| (*ap->apr_flush)(ap, how); |
| break; |
| case 1 : |
| for (ap = ap_proxies; ap->apr_p; ap++) |
| if (ap->apr_clear != NULL) |
| (*ap->apr_clear)(ap); |
| for (ap = ap_proxylist; ap; ap = ap->apr_next) |
| if (ap->apr_clear != NULL) |
| (*ap->apr_clear)(ap); |
| break; |
| default : |
| break; |
| } |
| } |