diff options
Diffstat (limited to 'sys/contrib/ipfilter/netinet/ip_raudio_pxy.c')
| -rw-r--r-- | sys/contrib/ipfilter/netinet/ip_raudio_pxy.c | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/sys/contrib/ipfilter/netinet/ip_raudio_pxy.c b/sys/contrib/ipfilter/netinet/ip_raudio_pxy.c new file mode 100644 index 0000000..607fd74 --- /dev/null +++ b/sys/contrib/ipfilter/netinet/ip_raudio_pxy.c @@ -0,0 +1,339 @@ +/* $FreeBSD$ */ + +/* + * $FreeBSD$ + * Copyright (C) 1998-2003 by Darren Reed + * + * See the IPFILTER.LICENCE file for details on licencing. + * + * $Id: ip_raudio_pxy.c,v 1.40.2.3 2005/02/04 10:22:55 darrenr Exp $ + */ + +#define IPF_RAUDIO_PROXY + + +int ippr_raudio_init __P((void)); +void ippr_raudio_fini __P((void)); +int ippr_raudio_new __P((fr_info_t *, ap_session_t *, nat_t *)); +int ippr_raudio_in __P((fr_info_t *, ap_session_t *, nat_t *)); +int ippr_raudio_out __P((fr_info_t *, ap_session_t *, nat_t *)); + +static frentry_t raudiofr; + +int raudio_proxy_init = 0; + + +/* + * Real Audio application proxy initialization. + */ +int ippr_raudio_init() +{ + bzero((char *)&raudiofr, sizeof(raudiofr)); + raudiofr.fr_ref = 1; + raudiofr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE; + MUTEX_INIT(&raudiofr.fr_lock, "Real Audio proxy rule lock"); + raudio_proxy_init = 1; + + return 0; +} + + +void ippr_raudio_fini() +{ + if (raudio_proxy_init == 1) { + MUTEX_DESTROY(&raudiofr.fr_lock); + raudio_proxy_init = 0; + } +} + + +/* + * Setup for a new proxy to handle Real Audio. + */ +int ippr_raudio_new(fin, aps, nat) +fr_info_t *fin; +ap_session_t *aps; +nat_t *nat; +{ + raudio_t *rap; + + KMALLOCS(aps->aps_data, void *, sizeof(raudio_t)); + if (aps->aps_data == NULL) + return -1; + + fin = fin; /* LINT */ + nat = nat; /* LINT */ + + bzero(aps->aps_data, sizeof(raudio_t)); + rap = aps->aps_data; + aps->aps_psiz = sizeof(raudio_t); + rap->rap_mode = RAP_M_TCP; /* default is for TCP */ + return 0; +} + + + +int ippr_raudio_out(fin, aps, nat) +fr_info_t *fin; +ap_session_t *aps; +nat_t *nat; +{ + raudio_t *rap = aps->aps_data; + unsigned char membuf[512 + 1], *s; + u_short id = 0; + tcphdr_t *tcp; + int off, dlen; + int len = 0; + mb_t *m; + + nat = nat; /* LINT */ + + /* + * If we've already processed the start messages, then nothing left + * for the proxy to do. + */ + if (rap->rap_eos == 1) + return 0; + + m = fin->fin_m; + tcp = (tcphdr_t *)fin->fin_dp; + off = (char *)tcp - (char *)fin->fin_ip; + off += (TCP_OFF(tcp) << 2) + fin->fin_ipoff; + +#ifdef __sgi + dlen = fin->fin_plen - off; +#else + dlen = MSGDSIZE(m) - off; +#endif + if (dlen <= 0) + return 0; + + if (dlen > sizeof(membuf)) + dlen = sizeof(membuf); + + bzero((char *)membuf, sizeof(membuf)); + COPYDATA(m, off, dlen, (char *)membuf); + /* + * In all the startup parsing, ensure that we don't go outside + * the packet buffer boundary. + */ + /* + * Look for the start of connection "PNA" string if not seen yet. + */ + if (rap->rap_seenpna == 0) { + s = (u_char *)memstr("PNA", (char *)membuf, 3, dlen); + if (s == NULL) + return 0; + s += 3; + rap->rap_seenpna = 1; + } else + s = membuf; + + /* + * Directly after the PNA will be the version number of this + * connection. + */ + if (rap->rap_seenpna == 1 && rap->rap_seenver == 0) { + if ((s + 1) - membuf < dlen) { + rap->rap_version = (*s << 8) | *(s + 1); + s += 2; + rap->rap_seenver = 1; + } else + return 0; + } + + /* + * Now that we've been past the PNA and version number, we're into the + * startup messages block. This ends when a message with an ID of 0. + */ + while ((rap->rap_eos == 0) && ((s + 1) - membuf < dlen)) { + if (rap->rap_gotid == 0) { + id = (*s << 8) | *(s + 1); + s += 2; + rap->rap_gotid = 1; + if (id == RA_ID_END) { + rap->rap_eos = 1; + break; + } + } else if (rap->rap_gotlen == 0) { + len = (*s << 8) | *(s + 1); + s += 2; + rap->rap_gotlen = 1; + } + + if (rap->rap_gotid == 1 && rap->rap_gotlen == 1) { + if (id == RA_ID_UDP) { + rap->rap_mode &= ~RAP_M_TCP; + rap->rap_mode |= RAP_M_UDP; + rap->rap_plport = (*s << 8) | *(s + 1); + } else if (id == RA_ID_ROBUST) { + rap->rap_mode |= RAP_M_ROBUST; + rap->rap_prport = (*s << 8) | *(s + 1); + } + s += len; + rap->rap_gotlen = 0; + rap->rap_gotid = 0; + } + } + return 0; +} + + +int ippr_raudio_in(fin, aps, nat) +fr_info_t *fin; +ap_session_t *aps; +nat_t *nat; +{ + unsigned char membuf[IPF_MAXPORTLEN + 1], *s; + tcphdr_t *tcp, tcph, *tcp2 = &tcph; + raudio_t *rap = aps->aps_data; + struct in_addr swa, swb; + int off, dlen, slen; + int a1, a2, a3, a4; + u_short sp, dp; + fr_info_t fi; + tcp_seq seq; + nat_t *nat2; + u_char swp; + ip_t *ip; + mb_t *m; + + /* + * Wait until we've seen the end of the start messages and even then + * only proceed further if we're using UDP. If they want to use TCP + * then data is sent back on the same channel that is already open. + */ + if (rap->rap_sdone != 0) + return 0; + + m = fin->fin_m; + tcp = (tcphdr_t *)fin->fin_dp; + off = (char *)tcp - (char *)fin->fin_ip; + off += (TCP_OFF(tcp) << 2) + fin->fin_ipoff; + +#ifdef __sgi + dlen = fin->fin_plen - off; +#else + dlen = MSGDSIZE(m) - off; +#endif + if (dlen <= 0) + return 0; + + if (dlen > sizeof(membuf)) + dlen = sizeof(membuf); + + bzero((char *)membuf, sizeof(membuf)); + COPYDATA(m, off, dlen, (char *)membuf); + + seq = ntohl(tcp->th_seq); + /* + * Check to see if the data in this packet is of interest to us. + * We only care for the first 19 bytes coming back from the server. + */ + if (rap->rap_sseq == 0) { + s = (u_char *)memstr("PNA", (char *)membuf, 3, dlen); + if (s == NULL) + return 0; + a1 = s - membuf; + dlen -= a1; + a1 = 0; + rap->rap_sseq = seq; + a2 = MIN(dlen, sizeof(rap->rap_svr)); + } else if (seq <= rap->rap_sseq + sizeof(rap->rap_svr)) { + /* + * seq # which is the start of data and from that the offset + * into the buffer array. + */ + a1 = seq - rap->rap_sseq; + a2 = MIN(dlen, sizeof(rap->rap_svr)); + a2 -= a1; + s = membuf; + } else + return 0; + + for (a3 = a1, a4 = a2; (a4 > 0) && (a3 < 19) && (a3 >= 0); a4--,a3++) { + rap->rap_sbf |= (1 << a3); + rap->rap_svr[a3] = *s++; + } + + if ((rap->rap_sbf != 0x7ffff) || (!rap->rap_eos)) /* 19 bits */ + return 0; + rap->rap_sdone = 1; + + s = (u_char *)rap->rap_svr + 11; + if (((*s << 8) | *(s + 1)) == RA_ID_ROBUST) { + s += 2; + rap->rap_srport = (*s << 8) | *(s + 1); + } + + ip = fin->fin_ip; + swp = ip->ip_p; + swa = ip->ip_src; + swb = ip->ip_dst; + + ip->ip_p = IPPROTO_UDP; + ip->ip_src = nat->nat_inip; + ip->ip_dst = nat->nat_oip; + + bcopy((char *)fin, (char *)&fi, sizeof(fi)); + bzero((char *)tcp2, sizeof(*tcp2)); + TCP_OFF_A(tcp2, 5); + fi.fin_state = NULL; + fi.fin_nat = NULL; + fi.fin_flx |= FI_IGNORE; + fi.fin_dp = (char *)tcp2; + fi.fin_fr = &raudiofr; + fi.fin_dlen = sizeof(*tcp2); + fi.fin_plen = fi.fin_hlen + sizeof(*tcp2); + tcp2->th_win = htons(8192); + slen = ip->ip_len; + ip->ip_len = fin->fin_hlen + sizeof(*tcp); + + if (((rap->rap_mode & RAP_M_UDP_ROBUST) == RAP_M_UDP_ROBUST) && + (rap->rap_srport != 0)) { + dp = rap->rap_srport; + sp = rap->rap_prport; + tcp2->th_sport = htons(sp); + tcp2->th_dport = htons(dp); + fi.fin_data[0] = dp; + fi.fin_data[1] = sp; + fi.fin_out = 0; + nat2 = nat_new(&fi, nat->nat_ptr, NULL, + NAT_SLAVE|IPN_UDP | (sp ? 0 : SI_W_SPORT), + NAT_OUTBOUND); + if (nat2 != NULL) { + (void) nat_proto(&fi, nat2, IPN_UDP); + nat_update(&fi, nat2, nat2->nat_ptr); + + (void) fr_addstate(&fi, NULL, (sp ? 0 : SI_W_SPORT)); + if (fi.fin_state != NULL) + fr_statederef(&fi, (ipstate_t **)&fi.fin_state); + } + } + + if ((rap->rap_mode & RAP_M_UDP) == RAP_M_UDP) { + sp = rap->rap_plport; + tcp2->th_sport = htons(sp); + tcp2->th_dport = 0; /* XXX - don't specify remote port */ + fi.fin_data[0] = sp; + fi.fin_data[1] = 0; + fi.fin_out = 1; + nat2 = nat_new(&fi, nat->nat_ptr, NULL, + NAT_SLAVE|IPN_UDP|SI_W_DPORT, + NAT_OUTBOUND); + if (nat2 != NULL) { + (void) nat_proto(&fi, nat2, IPN_UDP); + nat_update(&fi, nat2, nat2->nat_ptr); + + (void) fr_addstate(&fi, NULL, SI_W_DPORT); + if (fi.fin_state != NULL) + fr_statederef(&fi, (ipstate_t **)&fi.fin_state); + } + } + + ip->ip_p = swp; + ip->ip_len = slen; + ip->ip_src = swa; + ip->ip_dst = swb; + return 0; +} |
