/* * $Id: ip_rcmd_pxy.c,v 1.4.2.4 2000/11/01 14:34:20 darrenr Exp $ */ /* * Simple RCMD transparent proxy for in-kernel use. For use with the NAT * code. * $FreeBSD$ */ #if SOLARIS && defined(_KERNEL) extern kmutex_t ipf_rw; #endif #define isdigit(x) ((x) >= '0' && (x) <= '9') #define IPF_RCMD_PROXY int ippr_rcmd_init __P((void)); int ippr_rcmd_new __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *)); int ippr_rcmd_out __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *)); u_short ipf_rcmd_atoi __P((char *)); int ippr_rcmd_portmsg __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *)); static frentry_t rcmdfr; /* * RCMD application proxy initialization. */ int ippr_rcmd_init() { bzero((char *)&rcmdfr, sizeof(rcmdfr)); rcmdfr.fr_ref = 1; rcmdfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE; return 0; } /* * Setup for a new RCMD proxy. */ int ippr_rcmd_new(fin, ip, aps, nat) fr_info_t *fin; ip_t *ip; ap_session_t *aps; nat_t *nat; { tcphdr_t *tcp = (tcphdr_t *)fin->fin_dp; aps->aps_psiz = sizeof(u_32_t); KMALLOCS(aps->aps_data, u_32_t *, sizeof(u_32_t)); if (aps->aps_data == NULL) return -1; *(u_32_t *)aps->aps_data = 0; aps->aps_sport = tcp->th_sport; aps->aps_dport = tcp->th_dport; return 0; } /* * ipf_rcmd_atoi - implement a simple version of atoi */ u_short ipf_rcmd_atoi(ptr) char *ptr; { register char *s = ptr, c; register u_short i = 0; while ((c = *s++) && isdigit(c)) { i *= 10; i += c - '0'; } return i; } int ippr_rcmd_portmsg(fin, ip, aps, nat) fr_info_t *fin; ip_t *ip; ap_session_t *aps; nat_t *nat; { char portbuf[8], *s; struct in_addr swip; u_short sp, dp; int off, dlen; tcphdr_t *tcp, tcph, *tcp2 = &tcph; fr_info_t fi; nat_t *ipn; mb_t *m; #if SOLARIS mb_t *m1; #endif tcp = (tcphdr_t *)fin->fin_dp; if (tcp->th_flags & TH_SYN) { *(u_32_t *)aps->aps_data = htonl(ntohl(tcp->th_seq) + 1); return 0; } if ((*(u_32_t *)aps->aps_data != 0) && (tcp->th_seq != *(u_32_t *)aps->aps_data)) return 0; off = (ip->ip_hl << 2) + (tcp->th_off << 2); #if SOLARIS m = fin->fin_qfm; dlen = msgdsize(m) - off; bzero(portbuf, sizeof(portbuf)); copyout_mblk(m, off, MIN(sizeof(portbuf), dlen), portbuf); #else m = *(mb_t **)fin->fin_mp; dlen = mbufchainlen(m) - off; bzero(portbuf, sizeof(portbuf)); m_copydata(m, off, MIN(sizeof(portbuf), dlen), portbuf); #endif portbuf[sizeof(portbuf) - 1] = '\0'; s = portbuf; sp = ipf_rcmd_atoi(s); if (!sp) return 0; /* * Add skeleton NAT entry for connection which will come back the * other way. */ sp = htons(sp); dp = htons(fin->fin_data[1]); ipn = nat_outlookup(fin->fin_ifp, IPN_TCP, nat->nat_p, nat->nat_inip, ip->ip_dst, (dp << 16) | sp, 0); if (ipn == NULL) { int slen; slen = ip->ip_len; ip->ip_len = fin->fin_hlen + sizeof(*tcp); bcopy((char *)fin, (char *)&fi, sizeof(fi)); bzero((char *)tcp2, sizeof(*tcp2)); tcp2->th_win = htons(8192); tcp2->th_sport = sp; tcp2->th_dport = 0; /* XXX - don't specify remote port */ tcp2->th_off = 5; fi.fin_data[0] = ntohs(sp); fi.fin_data[1] = 0; fi.fin_dp = (char *)tcp2; fi.fin_dlen = sizeof(*tcp2); swip = ip->ip_src; ip->ip_src = nat->nat_inip; ipn = nat_new(nat->nat_ptr, ip, &fi, IPN_TCP|FI_W_DPORT, NAT_OUTBOUND); if (ipn != NULL) { ipn->nat_age = fr_defnatage; fi.fin_fr = &rcmdfr; (void) fr_addstate(ip, &fi, FI_W_DPORT); } ip->ip_len = slen; ip->ip_src = swip; } return 0; } int ippr_rcmd_out(fin, ip, aps, nat) fr_info_t *fin; ip_t *ip; ap_session_t *aps; nat_t *nat; { return ippr_rcmd_portmsg(fin, ip, aps, nat); }