/* $NetBSD: ip_raudio_pxy.c,v 1.5 2000/05/11 19:46:06 veego Exp $ */ /* * Id: ip_raudio_pxy.c,v 1.7.2.1 2000/05/06 11:19:33 darrenr Exp */ #if SOLARIS && defined(_KERNEL) extern kmutex_t ipf_rw; #endif #define IPF_RAUDIO_PROXY int ippr_raudio_init __P((void)); int ippr_raudio_new __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *)); int ippr_raudio_in __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *)); int ippr_raudio_out __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *)); static frentry_t raudiofr; /* * 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; return 0; } /* * Setup for a new proxy to handle Real Audio. */ int ippr_raudio_new(fin, ip, aps, nat) fr_info_t *fin; ip_t *ip; 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; 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, ip, aps, nat) fr_info_t *fin; ip_t *ip; 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; #if SOLARIS mb_t *m1; #endif /* * If we've already processed the start messages, then nothing left * for the proxy to do. */ if (rap->rap_eos == 1) return 0; tcp = (tcphdr_t *)fin->fin_dp; off = (ip->ip_hl << 2) + (tcp->th_off << 2); bzero(membuf, sizeof(membuf)); #if SOLARIS m = fin->fin_qfm; dlen = msgdsize(m) - off; if (dlen <= 0) return 0; copyout_mblk(m, off, MIN(sizeof(membuf), dlen), (char *)membuf); #else m = *(mb_t **)fin->fin_mp; dlen = mbufchainlen(m) - off; if (dlen <= 0) return 0; m_copydata(m, off, MIN(sizeof(membuf), dlen), (char *)membuf); #endif /* * 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, ip, aps, nat) fr_info_t *fin; ip_t *ip; 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; u_int a1, a2, a3, a4; int off, dlen, slen; u_short sp, dp; fr_info_t fi; tcp_seq seq; nat_t *ipn; u_char swp; mb_t *m; #if SOLARIS mb_t *m1; #endif /* * 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; tcp = (tcphdr_t *)fin->fin_dp; off = (ip->ip_hl << 2) + (tcp->th_off << 2); m = *(mb_t **)fin->fin_mp; #if SOLARIS m = fin->fin_qfm; dlen = msgdsize(m) - off; if (dlen <= 0) return 0; bzero(membuf, sizeof(membuf)); copyout_mblk(m, off, MIN(sizeof(membuf), dlen), (char *)membuf); #else dlen = mbufchainlen(m) - off; if (dlen <= 0) return 0; bzero(membuf, sizeof(membuf)); m_copydata(m, off, MIN(sizeof(membuf), dlen), (char *)membuf); #endif 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); } 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)); tcp2->th_off = 5; fi.fin_dp = (char *)tcp2; fi.fin_fr = &raudiofr; 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; ipn = nat_new(nat->nat_ptr, ip, &fi, IPN_UDP | (sp ? 0 : FI_W_SPORT), NAT_OUTBOUND); if (ipn != NULL) { ipn->nat_age = fr_defnatage; (void) fr_addstate(ip, &fi, sp ? 0 : FI_W_SPORT); } } 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; ipn = nat_new(nat->nat_ptr, ip, &fi, IPN_UDP|FI_W_DPORT, NAT_OUTBOUND); if (ipn != NULL) { ipn->nat_age = fr_defnatage; (void) fr_addstate(ip, &fi, FI_W_DPORT); } } ip->ip_p = swp; ip->ip_len = slen; ip->ip_src = swa; ip->ip_dst = swb; return 0; }