Import version 3.2alpha7
(they're currently in src/contrib/ipfilter/ipfilter/ by mistake, if someone from core would like to delete that directory with three files as I'm not meant to do that :)
This commit is contained in:
Darren Reed
parent
0eab801c99
commit
acdb2ce24a
204
contrib/ipfilter/ip_ftp_pxy.c
Normal file
204
contrib/ipfilter/ip_ftp_pxy.c
Normal file
@ -0,0 +1,204 @@
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/*
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* Simple FTP transparent proxy for in-kernel.
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*/
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#define isdigit(x) ((x) >= '0' && (x) <= '9')
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#define IPF_FTP_PROXY
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#define IPF_MINPORTLEN 18
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#define IPF_MAXPORTLEN 30
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int ippr_ftp_init(fin, ip, tcp, aps, nat)
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fr_info_t *fin;
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ip_t *ip;
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tcphdr_t *tcp;
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ap_session_t *aps;
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nat_t *nat;
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{
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aps->aps_sport = tcp->th_sport;
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aps->aps_dport = tcp->th_dport;
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return 0;
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}
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int ippr_ftp_in(fin, ip, tcp, aps, nat)
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fr_info_t *fin;
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ip_t *ip;
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tcphdr_t *tcp;
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ap_session_t *aps;
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nat_t *nat;
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{
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int ch = 0;
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u_long sum1, sum2;
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if (tcp->th_dport != aps->aps_dport) {
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sum2 = (u_long)ntohl(tcp->th_ack);
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if (aps->aps_seqoff && (sum2 > aps->aps_after)) {
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sum1 = (u_long)aps->aps_seqoff;
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tcp->th_ack = htonl(sum2 - sum1);
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return 2;
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}
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}
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return 0;
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}
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u_short ipf_ftp_atoi(ptr)
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char **ptr;
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{
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register char *s = *ptr, c;
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register u_char i = 0, j = 0;
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while ((c = *s++) && isdigit(c)) {
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i *= 10;
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i += c - '0';
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}
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if (c != ',') {
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*ptr = NULL;
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return 0;
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}
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while ((c = *s++) && isdigit(c)) {
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j *= 10;
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j += c - '0';
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}
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*ptr = s;
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return (i << 8) | j;
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}
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int ippr_ftp_out(fin, ip, tcp, aps, nat)
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fr_info_t *fin;
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ip_t *ip;
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tcphdr_t *tcp;
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ap_session_t *aps;
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nat_t *nat;
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{
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register u_long sum1, sum2, sumd;
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char newbuf[IPF_MAXPORTLEN+1];
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char portbuf[IPF_MAXPORTLEN+1], *s, c;
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int ch = 0, off = (ip->ip_hl << 2) + (tcp->th_off << 2), len;
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u_int a1, a2, a3, a4;
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u_short a5, a6;
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int olen, dlen, nlen, inc = 0, blen;
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tcphdr_t tcph, *tcp2 = &tcph;
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void *savep;
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nat_t *ipn;
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struct in_addr swip;
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#if SOLARIS
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mblk_t *m1, *m = *(mblk_t **)fin->fin_mp;
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dlen = m->b_wptr - m->b_rptr - off;
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blen = m->b_datap->db_lim - m->b_datap->db_base;
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bzero(portbuf, sizeof(portbuf));
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copyout_mblk(m, off, portbuf, MIN(sizeof(portbuf), dlen));
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#else
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struct mbuf *m1, *m = *(struct mbuf **)fin->fin_mp;
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dlen = m->m_len - off;
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# if BSD >= 199306
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blen = (MLEN - m->m_len) - (m->m_data - m->m_dat);
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# else
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blen = (MLEN - m->m_len) - m->m_off;
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# endif
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if (blen < 0)
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panic("blen < 0 - size of mblk/mbuf wrong");
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bzero(portbuf, sizeof(portbuf));
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m_copydata(m, off, MIN(sizeof(portbuf), dlen), portbuf);
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#endif
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portbuf[IPF_MAXPORTLEN] = '\0';
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len = MIN(32, dlen);
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if ((len < IPF_MINPORTLEN) || strncmp(portbuf, "PORT ", 5))
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goto adjust_seqack;
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/*
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* Skip the PORT command + space
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*/
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s = portbuf + 5;
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/*
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* Pick out the address components, two at a time.
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*/
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(void) ipf_ftp_atoi(&s);
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if (!s)
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goto adjust_seqack;
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(void) ipf_ftp_atoi(&s);
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if (!s)
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goto adjust_seqack;
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a5 = ipf_ftp_atoi(&s);
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if (!s)
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goto adjust_seqack;
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/*
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* check for CR-LF at the end.
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*/
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if (*s != '\n' || *(s - 1) != '\r')
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goto adjust_seqack;
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a6 = a5 & 0xff;
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a5 >>= 8;
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/*
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* Calculate new address parts for PORT command
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*/
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a1 = ntohl(ip->ip_src.s_addr);
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a2 = (a1 >> 16) & 0xff;
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a3 = (a1 >> 8) & 0xff;
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a4 = a1 & 0xff;
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a1 >>= 24;
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olen = s - portbuf + 1;
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(void) sprintf(newbuf, "PORT %d,%d,%d,%d,%d,%d\r\n",
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a1, a2, a3, a4, a5, a6);
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nlen = strlen(newbuf);
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inc = nlen - olen;
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if (tcp->th_seq > aps->aps_after) {
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aps->aps_after = ntohl(tcp->th_seq) + dlen;
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aps->aps_seqoff += inc;
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}
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#if SOLARIS
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if (inc && dlen)
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if ((inc < 0) || (blen >= dlen)) {
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bcopy(m->b_rptr + off,
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m->b_rptr + off + aps->aps_seqoff, dlen);
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}
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for (m1 = m; m1->b_cont; m1 = m1->b_cont)
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;
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m1->b_wptr += inc;
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copyin_mblk(m, off, newbuf, strlen(newbuf));
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#else
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if (inc && dlen)
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if ((inc < 0) || (blen >= dlen)) {
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bcopy((char *)ip + off,
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(char *)ip + off + aps->aps_seqoff, dlen);
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}
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m->m_len += inc;
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m_copyback(m, off, nlen, newbuf);
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#endif
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ip->ip_len += inc;
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ch = 1;
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/*
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* Add skeleton NAT entry for connection which will come back the
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* other way.
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*/
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savep = fin->fin_dp;
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fin->fin_dp = (char *)tcp2;
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tcp2->th_sport = htons(a5 << 8 | a6);
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tcp2->th_dport = htons(20);
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swip = ip->ip_src;
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ip->ip_src = nat->nat_inip;
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if ((ipn = nat_new(nat->nat_ptr, ip, fin, IPN_TCP, NAT_OUTBOUND)))
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ipn->nat_age = fr_defnatage;
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ip->ip_src = swip;
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fin->fin_dp = (char *)savep;
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adjust_seqack:
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if (tcp->th_dport == aps->aps_dport) {
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sum2 = (u_long)ntohl(tcp->th_seq);
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if (aps->aps_seqoff && (sum2 > aps->aps_after)) {
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sum1 = (u_long)aps->aps_seqoff;
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tcp->th_seq = htonl(sum2 + sum1);
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ch = 1;
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}
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}
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return ch ? 2 : 0;
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}
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271
contrib/ipfilter/ip_proxy.c
Normal file
271
contrib/ipfilter/ip_proxy.c
Normal file
@ -0,0 +1,271 @@
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/*
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* (C)opyright 1997 by Darren Reed.
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*
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* Redistribution and use in source and binary forms are permitted
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* provided that this notice is preserved and due credit is given
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* to the original author and the contributors.
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*/
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#if !defined(lint) && defined(LIBC_SCCS)
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static char rcsid[] = "$Id: ip_proxy.c,v 2.0.2.3 1997/05/24 07:36:22 darrenr Exp $";
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#endif
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#if defined(__FreeBSD__) && defined(KERNEL) && !defined(_KERNEL)
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# define _KERNEL
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#endif
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#if !defined(_KERNEL) && !defined(KERNEL)
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# include <stdio.h>
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# include <string.h>
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# include <stdlib.h>
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#endif
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#include <sys/errno.h>
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/time.h>
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#include <sys/file.h>
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#include <sys/ioctl.h>
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#include <sys/fcntl.h>
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#include <sys/uio.h>
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#include <sys/protosw.h>
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#include <sys/socket.h>
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#ifdef _KERNEL
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# include <sys/systm.h>
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#endif
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#if !defined(__SVR4) && !defined(__svr4__)
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# include <sys/mbuf.h>
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#else
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# include <sys/byteorder.h>
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# include <sys/dditypes.h>
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# include <sys/stream.h>
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# include <sys/kmem.h>
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#endif
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#if __FreeBSD__ > 2
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# include <sys/queue.h>
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#endif
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#include <net/if.h>
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#ifdef sun
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# include <net/af.h>
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#endif
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#include <net/route.h>
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/ip.h>
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#include <netinet/ip_var.h>
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#include <netinet/tcp.h>
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#include <netinet/udp.h>
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#include <netinet/tcpip.h>
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#include <netinet/ip_icmp.h>
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#include "netinet/ip_compat.h"
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#include "netinet/ip_fil.h"
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#include "netinet/ip_proxy.h"
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#include "netinet/ip_nat.h"
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#include "netinet/ip_state.h"
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#ifndef MIN
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#define MIN(a,b) (((a)<(b))?(a):(b))
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#endif
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static ap_session_t *ap_find __P((ip_t *, tcphdr_t *));
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static ap_session_t *ap_new_session __P((aproxy_t *, ip_t *, tcphdr_t *,
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fr_info_t *, nat_t *));
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#define AP_SESS_SIZE 53
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#ifdef _KERNEL
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#include "netinet/ip_ftp_pxy.c"
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#endif
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ap_session_t *ap_sess_tab[AP_SESS_SIZE];
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aproxy_t ap_proxies[] = {
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#ifdef IPF_FTP_PROXY
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{ "ftp", (char)IPPROTO_TCP, 0, 0, ippr_ftp_init, ippr_ftp_in, ippr_ftp_out },
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#endif
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{ "", '\0', 0, 0, NULL, NULL }
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};
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int ap_ok(ip, tcp, nat)
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ip_t *ip;
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tcphdr_t *tcp;
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ipnat_t *nat;
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{
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aproxy_t *apr = nat->in_apr;
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u_short dport = nat->in_dport;
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if (!apr || (apr && (apr->apr_flags & APR_DELETE)) ||
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(ip->ip_p != apr->apr_p))
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return 0;
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if ((tcp && (tcp->th_dport != dport)) || (!tcp && dport))
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return 0;
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return 1;
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}
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static ap_session_t *ap_find(ip, tcp)
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ip_t *ip;
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tcphdr_t *tcp;
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{
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struct in_addr src = ip->ip_src, dst = ip->ip_dst;
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register u_long hv;
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register u_short sp, dp;
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register ap_session_t *aps;
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register u_char p = ip->ip_p;
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hv = ip->ip_src.s_addr ^ ip->ip_dst.s_addr;
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hv *= 651733;
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if (tcp) {
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sp = tcp->th_sport;
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dp = tcp->th_dport;
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hv ^= (sp + dp);
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hv *= 5;
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}
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hv %= AP_SESS_SIZE;
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for (aps = ap_sess_tab[hv]; aps; aps = aps->aps_next)
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if ((aps->aps_p == p) &&
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IPPAIR(aps->aps_src, aps->aps_dst, src, dst)) {
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if (tcp) {
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if (PAIRS(aps->aps_sport, aps->aps_dport,
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sp, dp))
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break;
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} else
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break;
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}
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return aps;
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}
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static ap_session_t *ap_new_session(apr, ip, tcp, fin, nat)
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aproxy_t *apr;
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ip_t *ip;
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tcphdr_t *tcp;
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fr_info_t *fin;
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nat_t *nat;
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{
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register ap_session_t *aps;
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u_short dport;
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u_long hv;
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if (!apr || (apr && (apr->apr_flags & APR_DELETE)) ||
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(ip->ip_p != apr->apr_p))
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return NULL;
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dport = nat->nat_ptr->in_dport;
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if ((tcp && (tcp->th_dport != dport)) || (!tcp && dport))
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return NULL;
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hv = ip->ip_src.s_addr ^ ip->ip_dst.s_addr;
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hv *= 651733;
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if (tcp) {
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hv ^= (tcp->th_sport + tcp->th_dport);
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hv *= 5;
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}
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hv %= AP_SESS_SIZE;
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KMALLOC(aps, ap_session_t *, sizeof(*aps));
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if (!aps)
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return NULL;
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bzero((char *)aps, sizeof(aps));
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apr->apr_ref++;
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aps->aps_apr = apr;
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aps->aps_src = ip->ip_src;
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aps->aps_dst = ip->ip_dst;
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aps->aps_p = ip->ip_p;
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aps->aps_tout = 1200; /* XXX */
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if (tcp) {
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if (ip->ip_p == IPPROTO_TCP) {
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aps->aps_seqoff = 0;
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aps->aps_ackoff = 0;
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aps->aps_state[0] = 0;
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aps->aps_state[1] = 0;
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}
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aps->aps_sport = tcp->th_sport;
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aps->aps_dport = tcp->th_dport;
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}
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aps->aps_data = NULL;
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aps->aps_psiz = 0;
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aps->aps_next = ap_sess_tab[hv];
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ap_sess_tab[hv] = aps;
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(void) (*apr->apr_init)(fin, ip, tcp, aps, nat);
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return aps;
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}
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int ap_check(ip, tcp, fin, nat)
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ip_t *ip;
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tcphdr_t *tcp;
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fr_info_t *fin;
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nat_t *nat;
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{
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ap_session_t *aps;
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aproxy_t *apr;
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int err;
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if (!(fin->fin_fi.fi_fl & FI_TCPUDP))
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tcp = NULL;
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if ((aps = ap_find(ip, tcp)) ||
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(aps = ap_new_session(nat->nat_ptr->in_apr, ip, tcp, fin, nat))) {
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if (ip->ip_p == IPPROTO_TCP)
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fr_tcp_age(&aps->aps_tout, aps->aps_state, ip, fin,
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tcp->th_sport == aps->aps_sport);
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apr = aps->aps_apr;
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err = 0;
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if (fin->fin_out) {
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if (apr->apr_outpkt)
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err = (*apr->apr_outpkt)(fin, ip, tcp,
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aps, nat);
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} else {
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if (apr->apr_inpkt)
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err = (*apr->apr_inpkt)(fin, ip, tcp,
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aps, nat);
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}
|
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if (err == 2) {
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tcp->th_sum = fr_tcpsum(fin->fin_mp, ip, tcp);
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err = 0;
|
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}
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return err;
|
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}
|
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return -1;
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}
|
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|
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aproxy_t *ap_match(pr, name)
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char pr;
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char *name;
|
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{
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aproxy_t *ap;
|
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|
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for (ap = ap_proxies; ap->apr_p; ap++)
|
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if ((ap->apr_p == pr) &&
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!strncmp(name, ap->apr_label, sizeof(ap->apr_label)))
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return ap;
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return NULL;
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}
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|
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void ap_free(ap)
|
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aproxy_t *ap;
|
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{
|
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KFREE(ap);
|
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}
|
||||
|
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|
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void aps_free(aps)
|
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ap_session_t *aps;
|
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{
|
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if (aps->aps_data && aps->aps_psiz)
|
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KFREES(aps->aps_data, aps->aps_psiz);
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KFREE(aps);
|
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}
|
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|
||||
|
||||
void ap_unload()
|
||||
{
|
||||
ap_session_t *aps;
|
||||
int i;
|
||||
|
||||
for (i = 0; i < AP_SESS_SIZE; i++)
|
||||
while (aps = ap_sess_tab[i]) {
|
||||
ap_sess_tab[i] = aps->aps_next;
|
||||
aps_free(aps);
|
||||
}
|
||||
}
|
||||
89
contrib/ipfilter/ip_proxy.h
Normal file
89
contrib/ipfilter/ip_proxy.h
Normal file
@ -0,0 +1,89 @@
|
||||
/*
|
||||
* (C)opyright 1997 by Darren Reed.
|
||||
*
|
||||
* Redistribution and use in source and binary forms are permitted
|
||||
* provided that this notice is preserved and due credit is given
|
||||
* to the original author and the contributors.
|
||||
*
|
||||
* $Id: ip_proxy.h,v 2.0.2.2 1997/05/24 07:36:44 darrenr Exp $
|
||||
*/
|
||||
|
||||
#ifndef __IP_PROXY_H__
|
||||
#define __IP_PROXY_H__
|
||||
|
||||
#ifndef SOLARIS
|
||||
#define SOLARIS (defined(sun) && (defined(__svr4__) || defined(__SVR4)))
|
||||
#endif
|
||||
|
||||
#define APR_LABELLEN 16
|
||||
#define AP_SESS_SIZE 53
|
||||
|
||||
struct nat;
|
||||
|
||||
typedef struct ap_tcp {
|
||||
u_short apt_sport; /* source port */
|
||||
u_short apt_dport; /* destination port */
|
||||
short apt_seqoff; /* sequence # difference */
|
||||
short apt_ackoff; /* ack # difference */
|
||||
tcp_seq apt_after; /* don't change seq-off until after this */
|
||||
char apt_state[2]; /* connection state */
|
||||
} ap_tcp_t;
|
||||
|
||||
typedef struct ap_udp {
|
||||
u_short apu_sport; /* source port */
|
||||
u_short apu_dport; /* destination port */
|
||||
} ap_udp_t;
|
||||
|
||||
typedef struct ap_session {
|
||||
struct aproxy *aps_apr;
|
||||
struct in_addr aps_src; /* source IP# */
|
||||
struct in_addr aps_dst; /* destination IP# */
|
||||
u_char aps_p; /* protocol */
|
||||
union {
|
||||
struct ap_tcp apu_tcp;
|
||||
struct ap_udp apu_udp;
|
||||
} aps_un;
|
||||
u_int aps_flags;
|
||||
QUAD_T aps_bytes; /* bytes sent */
|
||||
QUAD_T aps_pkts; /* packets sent */
|
||||
time_t aps_tout; /* time left before expiring */
|
||||
void *aps_data; /* private data */
|
||||
int aps_psiz; /* size of private data */
|
||||
struct ap_session *aps_next;
|
||||
} ap_session_t ;
|
||||
|
||||
#define aps_sport aps_un.apu_tcp.apt_sport
|
||||
#define aps_dport aps_un.apu_tcp.apt_dport
|
||||
#define aps_seqoff aps_un.apu_tcp.apt_seqoff
|
||||
#define aps_ackoff aps_un.apu_tcp.apt_ackoff
|
||||
#define aps_sumoff aps_un.apu_tcp.apt_sumoff
|
||||
#define aps_state aps_un.apu_tcp.apt_state
|
||||
#define aps_after aps_un.apu_tcp.apt_after
|
||||
|
||||
|
||||
typedef struct aproxy {
|
||||
char apr_label[APR_LABELLEN]; /* Proxy label # */
|
||||
char apr_p; /* protocol */
|
||||
int apr_ref; /* +1 per rule referencing it */
|
||||
int apr_flags;
|
||||
int (* apr_init) __P((fr_info_t *, ip_t *, tcphdr_t *,
|
||||
ap_session_t *, struct nat *));
|
||||
int (* apr_inpkt) __P((fr_info_t *, ip_t *, tcphdr_t *,
|
||||
ap_session_t *, struct nat *));
|
||||
int (* apr_outpkt) __P((fr_info_t *, ip_t *, tcphdr_t *,
|
||||
ap_session_t *, struct nat *));
|
||||
} aproxy_t;
|
||||
|
||||
#define APR_DELETE 1
|
||||
|
||||
|
||||
extern ap_session_t *ap_sess_tab[AP_SESS_SIZE];
|
||||
extern aproxy_t ap_proxies[];
|
||||
|
||||
extern void ap_unload __P((void));
|
||||
extern void ap_free __P((aproxy_t *));
|
||||
extern void aps_free __P((ap_session_t *));
|
||||
extern int ap_check __P((ip_t *, tcphdr_t *, fr_info_t *, struct nat *));
|
||||
extern aproxy_t *ap_match __P((char, char *));
|
||||
|
||||
#endif /* __IP_PROXY_H__ */
|
||||
Loading…
Reference in New Issue
Block a user