1073 lines
23 KiB
C
1073 lines
23 KiB
C
/* $NetBSD: ip_ftp_pxy.c,v 1.26 2002/09/19 08:12:50 martti Exp $ */
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#include <sys/cdefs.h>
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__KERNEL_RCSID(1, "$NetBSD: ip_ftp_pxy.c,v 1.26 2002/09/19 08:12:50 martti Exp $");
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/*
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* Simple FTP transparent proxy for in-kernel use. For use with the NAT
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* code.
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*
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* Id: ip_ftp_pxy.c,v 2.7.2.38 2002/08/28 12:45:47 darrenr Exp
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*/
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#if SOLARIS && defined(_KERNEL)
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extern kmutex_t ipf_rw;
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#endif
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#define isdigit(x) ((x) >= '0' && (x) <= '9')
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#define isupper(x) (((unsigned)(x) >= 'A') && ((unsigned)(x) <= 'Z'))
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#define islower(x) (((unsigned)(x) >= 'a') && ((unsigned)(x) <= 'z'))
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#define isalpha(x) (isupper(x) || islower(x))
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#define toupper(x) (isupper(x) ? (x) : (x) - 'a' + 'A')
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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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#define IPF_MIN227LEN 39
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#define IPF_MAX227LEN 51
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#define IPF_FTPBUFSZ 96 /* This *MUST* be >= 53! */
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#define FTPXY_GO 0
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#define FTPXY_INIT 1
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#define FTPXY_USER_1 2
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#define FTPXY_USOK_1 3
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#define FTPXY_PASS_1 4
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#define FTPXY_PAOK_1 5
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#define FTPXY_AUTH_1 6
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#define FTPXY_AUOK_1 7
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#define FTPXY_ADAT_1 8
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#define FTPXY_ADOK_1 9
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#define FTPXY_ACCT_1 10
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#define FTPXY_ACOK_1 11
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#define FTPXY_USER_2 12
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#define FTPXY_USOK_2 13
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#define FTPXY_PASS_2 14
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#define FTPXY_PAOK_2 15
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int ippr_ftp_client __P((fr_info_t *, ip_t *, nat_t *, ftpinfo_t *, int));
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int ippr_ftp_complete __P((char *, size_t));
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int ippr_ftp_in __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *));
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int ippr_ftp_init __P((void));
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int ippr_ftp_new __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *));
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int ippr_ftp_out __P((fr_info_t *, ip_t *, ap_session_t *, nat_t *));
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int ippr_ftp_pasv __P((fr_info_t *, ip_t *, nat_t *, ftpside_t *, int));
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int ippr_ftp_port __P((fr_info_t *, ip_t *, nat_t *, ftpside_t *, int));
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int ippr_ftp_process __P((fr_info_t *, ip_t *, nat_t *, ftpinfo_t *, int));
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int ippr_ftp_server __P((fr_info_t *, ip_t *, nat_t *, ftpinfo_t *, int));
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int ippr_ftp_valid __P((int, char *, size_t));
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int ippr_ftp_server_valid __P((char *, size_t));
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int ippr_ftp_client_valid __P((char *, size_t));
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u_short ippr_ftp_atoi __P((char **));
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static frentry_t ftppxyfr;
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int ippr_ftp_pasvonly = 0;
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int ippr_ftp_insecure = 0;
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/*
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* Initialize local structures.
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*/
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int ippr_ftp_init()
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{
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bzero((char *)&ftppxyfr, sizeof(ftppxyfr));
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ftppxyfr.fr_ref = 1;
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ftppxyfr.fr_flags = FR_INQUE|FR_PASS|FR_QUICK|FR_KEEPSTATE;
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return 0;
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}
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int ippr_ftp_new(fin, ip, aps, nat)
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fr_info_t *fin;
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ip_t *ip;
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ap_session_t *aps;
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nat_t *nat;
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{
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ftpinfo_t *ftp;
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ftpside_t *f;
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KMALLOC(ftp, ftpinfo_t *);
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if (ftp == NULL)
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return -1;
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aps->aps_data = ftp;
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aps->aps_psiz = sizeof(ftpinfo_t);
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bzero((char *)ftp, sizeof(*ftp));
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f = &ftp->ftp_side[0];
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f->ftps_rptr = f->ftps_buf;
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f->ftps_wptr = f->ftps_buf;
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f = &ftp->ftp_side[1];
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f->ftps_rptr = f->ftps_buf;
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f->ftps_wptr = f->ftps_buf;
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ftp->ftp_passok = FTPXY_INIT;
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return 0;
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}
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int ippr_ftp_port(fin, ip, nat, f, dlen)
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fr_info_t *fin;
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ip_t *ip;
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nat_t *nat;
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ftpside_t *f;
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int dlen;
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{
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tcphdr_t *tcp, tcph, *tcp2 = &tcph;
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char newbuf[IPF_FTPBUFSZ], *s;
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u_int a1, a2, a3, a4;
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struct in_addr swip;
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u_short a5, a6, sp;
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size_t nlen, olen;
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fr_info_t fi;
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int inc, off;
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nat_t *ipn;
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mb_t *m;
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#if SOLARIS
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mb_t *m1;
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#endif
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tcp = (tcphdr_t *)fin->fin_dp;
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/*
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* Check for client sending out PORT message.
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*/
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if (dlen < IPF_MINPORTLEN)
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return 0;
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off = fin->fin_hlen + (tcp->th_off << 2);
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/*
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* Skip the PORT command + space
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*/
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s = f->ftps_rptr + 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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a1 = ippr_ftp_atoi(&s);
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if (!s)
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return 0;
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a2 = ippr_ftp_atoi(&s);
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if (!s)
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return 0;
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/*
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* check that IP address in the PORT/PASV reply is the same as the
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* sender of the command - prevents using PORT for port scanning.
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*/
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a1 <<= 16;
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a1 |= a2;
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if (a1 != ntohl(nat->nat_inip.s_addr))
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return 0;
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a5 = ippr_ftp_atoi(&s);
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if (!s)
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return 0;
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if (*s == ')')
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s++;
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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')
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s--;
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if ((*s == '\r') && (*(s + 1) == '\n')) {
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s += 2;
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a6 = a5 & 0xff;
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} else
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return 0;
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a5 >>= 8;
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a5 &= 0xff;
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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 - f->ftps_rptr;
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/* DO NOT change this to snprintf! */
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(void) sprintf(newbuf, "%s %u,%u,%u,%u,%u,%u\r\n",
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"PORT", 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 ((inc + ip->ip_len) > 65535)
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return 0;
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#if !defined(_KERNEL)
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m = *((mb_t **)fin->fin_mp);
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bcopy(newbuf, (char *)m + off, nlen);
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#else
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# if SOLARIS
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m = fin->fin_qfm;
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for (m1 = m; m1->b_cont; m1 = m1->b_cont)
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;
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if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
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mblk_t *nm;
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/* alloc enough to keep same trailer space for lower driver */
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nm = allocb(nlen, BPRI_MED);
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PANIC((!nm),("ippr_ftp_out: allocb failed"));
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nm->b_band = m1->b_band;
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nm->b_wptr += nlen;
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m1->b_wptr -= olen;
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PANIC((m1->b_wptr < m1->b_rptr),
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("ippr_ftp_out: cannot handle fragmented data block"));
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linkb(m1, nm);
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} else {
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if (m1->b_datap->db_struiolim == m1->b_wptr)
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m1->b_datap->db_struiolim += inc;
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m1->b_datap->db_struioflag &= ~STRUIO_IP;
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m1->b_wptr += inc;
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}
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copyin_mblk(m, off, nlen, newbuf);
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# else
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m = *((mb_t **)fin->fin_mp);
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if (inc < 0)
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m_adj(m, inc);
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/* the mbuf chain will be extended if necessary by m_copyback() */
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m_copyback(m, off, nlen, newbuf);
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# ifdef M_PKTHDR
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if (!(m->m_flags & M_PKTHDR))
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m->m_pkthdr.len += inc;
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# endif
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# endif
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#endif
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if (inc != 0) {
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#if (SOLARIS || defined(__sgi)) && defined(_KERNEL)
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register u_32_t sum1, sum2;
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sum1 = ip->ip_len;
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sum2 = ip->ip_len + inc;
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/* Because ~1 == -2, We really need ~1 == -1 */
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if (sum1 > sum2)
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sum2--;
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sum2 -= sum1;
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sum2 = (sum2 & 0xffff) + (sum2 >> 16);
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fix_outcksum(fin, &ip->ip_sum, sum2);
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#endif
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ip->ip_len += inc;
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}
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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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sp = (a5 << 8 | a6);
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/*
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* Don't allow the PORT command to specify a port < 1024 due to
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* security crap.
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*/
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if (sp < 1024)
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return 0;
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/*
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* The server may not make the connection back from port 20, but
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* it is the most likely so use it here to check for a conflicting
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* mapping.
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*/
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bcopy((char *)fin, (char *)&fi, sizeof(fi));
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fi.fin_data[0] = sp;
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fi.fin_data[1] = fin->fin_data[1] - 1;
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ipn = nat_outlookup(&fi, IPN_TCP, nat->nat_p, nat->nat_inip,
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ip->ip_dst, 0);
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if (ipn == NULL) {
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int slen;
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slen = ip->ip_len;
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ip->ip_len = fin->fin_hlen + sizeof(*tcp2);
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bzero((char *)tcp2, sizeof(*tcp2));
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tcp2->th_win = htons(8192);
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tcp2->th_sport = htons(sp);
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tcp2->th_off = 5;
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tcp2->th_flags = TH_SYN;
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tcp2->th_dport = 0; /* XXX - don't specify remote port */
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fi.fin_data[1] = 0;
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fi.fin_dlen = sizeof(*tcp2);
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fi.fin_dp = (char *)tcp2;
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fi.fin_fr = &ftppxyfr;
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fi.fin_out = 1;
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swip = ip->ip_src;
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fi.fin_fi.fi_saddr = nat->nat_inip.s_addr;
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ip->ip_src = nat->nat_inip;
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ipn = nat_new(&fi, ip, nat->nat_ptr, NULL, IPN_TCP|FI_W_DPORT,
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NAT_OUTBOUND);
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if (ipn != NULL) {
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ipn->nat_age = fr_defnatage;
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(void) fr_addstate(ip, &fi, NULL,
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FI_W_DPORT|FI_IGNOREPKT);
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}
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ip->ip_len = slen;
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ip->ip_src = swip;
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}
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return inc;
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}
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int ippr_ftp_client(fin, ip, nat, ftp, dlen)
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fr_info_t *fin;
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nat_t *nat;
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ftpinfo_t *ftp;
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ip_t *ip;
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int dlen;
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{
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char *rptr, *wptr, cmd[6], c;
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ftpside_t *f;
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int inc, i;
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inc = 0;
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f = &ftp->ftp_side[0];
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rptr = f->ftps_rptr;
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wptr = f->ftps_wptr;
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for (i = 0; (i < 5) && (i < dlen); i++) {
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c = rptr[i];
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if (isalpha(c)) {
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cmd[i] = toupper(c);
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} else {
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cmd[i] = c;
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}
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}
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cmd[i] = '\0';
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ftp->ftp_incok = 0;
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if (!strncmp(cmd, "USER ", 5) || !strncmp(cmd, "XAUT ", 5)) {
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if (ftp->ftp_passok == FTPXY_ADOK_1 ||
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ftp->ftp_passok == FTPXY_AUOK_1) {
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ftp->ftp_passok = FTPXY_USER_2;
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ftp->ftp_incok = 1;
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} else {
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ftp->ftp_passok = FTPXY_USER_1;
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ftp->ftp_incok = 1;
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}
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} else if (!strncmp(cmd, "AUTH ", 5)) {
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ftp->ftp_passok = FTPXY_AUTH_1;
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ftp->ftp_incok = 1;
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} else if (!strncmp(cmd, "PASS ", 5)) {
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if (ftp->ftp_passok == FTPXY_USOK_1) {
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ftp->ftp_passok = FTPXY_PASS_1;
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ftp->ftp_incok = 1;
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} else if (ftp->ftp_passok == FTPXY_USOK_2) {
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ftp->ftp_passok = FTPXY_PASS_2;
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ftp->ftp_incok = 1;
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}
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} else if ((ftp->ftp_passok == FTPXY_AUOK_1) &&
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!strncmp(cmd, "ADAT ", 5)) {
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ftp->ftp_passok = FTPXY_ADAT_1;
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ftp->ftp_incok = 1;
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} else if ((ftp->ftp_passok == FTPXY_PAOK_1 ||
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ftp->ftp_passok == FTPXY_PAOK_2) &&
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!strncmp(cmd, "ACCT ", 5)) {
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ftp->ftp_passok = FTPXY_ACCT_1;
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ftp->ftp_incok = 1;
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} else if ((ftp->ftp_passok == FTPXY_GO) && !ippr_ftp_pasvonly &&
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!strncmp(cmd, "PORT ", 5)) {
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inc = ippr_ftp_port(fin, ip, nat, f, dlen);
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} else if (ippr_ftp_insecure && !ippr_ftp_pasvonly &&
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!strncmp(cmd, "PORT ", 5)) {
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inc = ippr_ftp_port(fin, ip, nat, f, dlen);
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}
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while ((*rptr++ != '\n') && (rptr < wptr))
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;
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f->ftps_rptr = rptr;
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return inc;
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}
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int ippr_ftp_pasv(fin, ip, nat, f, dlen)
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fr_info_t *fin;
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ip_t *ip;
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nat_t *nat;
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ftpside_t *f;
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int dlen;
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{
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tcphdr_t *tcp, tcph, *tcp2 = &tcph;
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struct in_addr swip, swip2;
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u_int a1, a2, a3, a4;
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u_short a5, a6, dp;
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fr_info_t fi;
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nat_t *ipn;
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int inc;
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char *s;
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#define PASV_REPLEN 24
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/*
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* Check for PASV reply message.
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*/
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if (dlen < IPF_MIN227LEN)
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return 0;
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else if (strncmp(f->ftps_rptr, "227 Entering Passive Mod", PASV_REPLEN))
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return 0;
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tcp = (tcphdr_t *)fin->fin_dp;
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/*
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* Skip the PORT command + space
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*/
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s = f->ftps_rptr + PASV_REPLEN;
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while (*s && !isdigit(*s))
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s++;
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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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a1 = ippr_ftp_atoi(&s);
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if (!s)
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return 0;
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a2 = ippr_ftp_atoi(&s);
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if (!s)
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return 0;
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/*
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* check that IP address in the PORT/PASV reply is the same as the
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* sender of the command - prevents using PORT for port scanning.
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*/
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a1 <<= 16;
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a1 |= a2;
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if (a1 != ntohl(nat->nat_oip.s_addr))
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return 0;
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a5 = ippr_ftp_atoi(&s);
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if (!s)
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return 0;
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if (*s == ')')
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s++;
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if (*s == '.')
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s++;
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if (*s == '\n')
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s--;
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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 == '\r') && (*(s + 1) == '\n')) {
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s += 2;
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a6 = a5 & 0xff;
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} else
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return 0;
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a5 >>= 8;
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/*
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* Calculate new address parts for 227 reply
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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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inc = 0;
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#if 0
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olen = s - f->ftps_rptr;
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(void) sprintf(newbuf, "%s %u,%u,%u,%u,%u,%u\r\n",
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"227 Entering Passive Mode", 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 ((inc + ip->ip_len) > 65535)
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return 0;
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#if !defined(_KERNEL)
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m = *((mb_t **)fin->fin_mp);
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m_copyback(m, off, nlen, newbuf);
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#else
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# if SOLARIS
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m = fin->fin_qfm;
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for (m1 = m; m1->b_cont; m1 = m1->b_cont)
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;
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if ((inc > 0) && (m1->b_datap->db_lim - m1->b_wptr < inc)) {
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mblk_t *nm;
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|
|
/* alloc enough to keep same trailer space for lower driver */
|
|
nm = allocb(nlen, BPRI_MED);
|
|
PANIC((!nm),("ippr_ftp_out: allocb failed"));
|
|
|
|
nm->b_band = m1->b_band;
|
|
nm->b_wptr += nlen;
|
|
|
|
m1->b_wptr -= olen;
|
|
PANIC((m1->b_wptr < m1->b_rptr),
|
|
("ippr_ftp_out: cannot handle fragmented data block"));
|
|
|
|
linkb(m1, nm);
|
|
} else {
|
|
m1->b_wptr += inc;
|
|
}
|
|
/*copyin_mblk(m, off, nlen, newbuf);*/
|
|
# else /* SOLARIS */
|
|
m = *((mb_t **)fin->fin_mp);
|
|
if (inc < 0)
|
|
m_adj(m, inc);
|
|
/* the mbuf chain will be extended if necessary by m_copyback() */
|
|
/*m_copyback(m, off, nlen, newbuf);*/
|
|
# endif /* SOLARIS */
|
|
#endif /* _KERNEL */
|
|
if (inc != 0) {
|
|
#if (SOLARIS || defined(__sgi)) && defined(_KERNEL)
|
|
register u_32_t sum1, sum2;
|
|
|
|
sum1 = ip->ip_len;
|
|
sum2 = ip->ip_len + inc;
|
|
|
|
/* Because ~1 == -2, We really need ~1 == -1 */
|
|
if (sum1 > sum2)
|
|
sum2--;
|
|
sum2 -= sum1;
|
|
sum2 = (sum2 & 0xffff) + (sum2 >> 16);
|
|
|
|
fix_outcksum(fin, &ip->ip_sum, sum2);
|
|
#endif /* SOLARIS || defined(__sgi) */
|
|
ip->ip_len += inc;
|
|
}
|
|
#endif /* 0 */
|
|
|
|
/*
|
|
* Add skeleton NAT entry for connection which will come back the
|
|
* other way.
|
|
*/
|
|
bcopy((char *)fin, (char *)&fi, sizeof(fi));
|
|
fi.fin_data[0] = 0;
|
|
dp = htons(fin->fin_data[1] - 1);
|
|
fi.fin_data[1] = ntohs(dp);
|
|
ipn = nat_outlookup(&fi, IPN_TCP, nat->nat_p, nat->nat_inip,
|
|
ip->ip_dst, 0);
|
|
if (ipn == NULL) {
|
|
int slen;
|
|
|
|
slen = ip->ip_len;
|
|
ip->ip_len = fin->fin_hlen + sizeof(*tcp2);
|
|
bzero((char *)tcp2, sizeof(*tcp2));
|
|
tcp2->th_win = htons(8192);
|
|
tcp2->th_sport = 0; /* XXX - fake it for nat_new */
|
|
tcp2->th_off = 5;
|
|
tcp2->th_flags = TH_SYN;
|
|
fi.fin_data[1] = a5 << 8 | a6;
|
|
fi.fin_dlen = sizeof(*tcp2);
|
|
tcp2->th_dport = htons(fi.fin_data[1]);
|
|
fi.fin_data[0] = 0;
|
|
fi.fin_dp = (char *)tcp2;
|
|
fi.fin_fr = &ftppxyfr;
|
|
fi.fin_out = 1;
|
|
swip = ip->ip_src;
|
|
swip2 = ip->ip_dst;
|
|
fi.fin_fi.fi_daddr = ip->ip_src.s_addr;
|
|
fi.fin_fi.fi_saddr = nat->nat_inip.s_addr;
|
|
ip->ip_dst = ip->ip_src;
|
|
ip->ip_src = nat->nat_inip;
|
|
ipn = nat_new(&fi, ip, nat->nat_ptr, NULL, IPN_TCP|FI_W_SPORT,
|
|
NAT_OUTBOUND);
|
|
if (ipn != NULL) {
|
|
ipn->nat_age = fr_defnatage;
|
|
(void) fr_addstate(ip, &fi, NULL,
|
|
FI_W_SPORT|FI_IGNOREPKT);
|
|
}
|
|
ip->ip_len = slen;
|
|
ip->ip_src = swip;
|
|
ip->ip_dst = swip2;
|
|
}
|
|
return inc;
|
|
}
|
|
|
|
|
|
int ippr_ftp_server(fin, ip, nat, ftp, dlen)
|
|
fr_info_t *fin;
|
|
ip_t *ip;
|
|
nat_t *nat;
|
|
ftpinfo_t *ftp;
|
|
int dlen;
|
|
{
|
|
char *rptr, *wptr;
|
|
ftpside_t *f;
|
|
int inc;
|
|
|
|
inc = 0;
|
|
f = &ftp->ftp_side[1];
|
|
rptr = f->ftps_rptr;
|
|
wptr = f->ftps_wptr;
|
|
|
|
if (!isdigit(*rptr) || !isdigit(*(rptr + 1)) || !isdigit(*(rptr + 2)))
|
|
return 0;
|
|
if (ftp->ftp_passok == FTPXY_GO) {
|
|
if (!strncmp(rptr, "227 ", 4))
|
|
inc = ippr_ftp_pasv(fin, ip, nat, f, dlen);
|
|
} else if (ippr_ftp_insecure && !strncmp(rptr, "227 ", 4)) {
|
|
inc = ippr_ftp_pasv(fin, ip, nat, f, dlen);
|
|
} else if (*rptr == '5' || *rptr == '4')
|
|
ftp->ftp_passok = FTPXY_INIT;
|
|
else if (ftp->ftp_incok) {
|
|
if (*rptr == '3') {
|
|
if (ftp->ftp_passok == FTPXY_ACCT_1)
|
|
ftp->ftp_passok = FTPXY_GO;
|
|
else
|
|
ftp->ftp_passok++;
|
|
} else if (*rptr == '2') {
|
|
switch (ftp->ftp_passok)
|
|
{
|
|
case FTPXY_USER_1 :
|
|
case FTPXY_USER_2 :
|
|
case FTPXY_PASS_1 :
|
|
case FTPXY_PASS_2 :
|
|
case FTPXY_ACCT_1 :
|
|
ftp->ftp_passok = FTPXY_GO;
|
|
break;
|
|
default :
|
|
ftp->ftp_passok += 3;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
ftp->ftp_incok = 0;
|
|
while ((*rptr++ != '\n') && (rptr < wptr))
|
|
;
|
|
f->ftps_rptr = rptr;
|
|
return inc;
|
|
}
|
|
|
|
|
|
/*
|
|
* Look to see if the buffer starts with something which we recognise as
|
|
* being the correct syntax for the FTP protocol.
|
|
*/
|
|
int ippr_ftp_client_valid(buf, len)
|
|
char *buf;
|
|
size_t len;
|
|
{
|
|
register char *s, c;
|
|
register size_t i = len;
|
|
|
|
if (i < 5)
|
|
return 2;
|
|
s = buf;
|
|
c = *s++;
|
|
i--;
|
|
|
|
if (isalpha(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if (isalpha(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if (isalpha(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if (isalpha(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if ((c != ' ') && (c != '\r'))
|
|
return 1;
|
|
} else if ((c != ' ') && (c != '\r'))
|
|
return 1;
|
|
} else
|
|
return 1;
|
|
} else
|
|
return 1;
|
|
} else
|
|
return 1;
|
|
for (; i; i--) {
|
|
c = *s++;
|
|
if (c == '\n')
|
|
return 0;
|
|
}
|
|
return 2;
|
|
}
|
|
|
|
|
|
int ippr_ftp_server_valid(buf, len)
|
|
char *buf;
|
|
size_t len;
|
|
{
|
|
register char *s, c;
|
|
register size_t i = len;
|
|
|
|
if (i < 5)
|
|
return 2;
|
|
s = buf;
|
|
c = *s++;
|
|
i--;
|
|
|
|
if (isdigit(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if (isdigit(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if (isdigit(c)) {
|
|
c = *s++;
|
|
i--;
|
|
if ((c != '-') && (c != ' '))
|
|
return 1;
|
|
} else
|
|
return 1;
|
|
} else
|
|
return 1;
|
|
} else
|
|
return 1;
|
|
for (; i; i--) {
|
|
c = *s++;
|
|
if (c == '\n')
|
|
return 0;
|
|
}
|
|
return 2;
|
|
}
|
|
|
|
|
|
int ippr_ftp_valid(side, buf, len)
|
|
int side;
|
|
char *buf;
|
|
size_t len;
|
|
{
|
|
int ret;
|
|
|
|
if (side == 0)
|
|
ret = ippr_ftp_client_valid(buf, len);
|
|
else
|
|
ret = ippr_ftp_server_valid(buf, len);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
* rv == 0 for outbound processing,
|
|
* rv == 1 for inbound processing.
|
|
*/
|
|
int ippr_ftp_process(fin, ip, nat, ftp, rv)
|
|
fr_info_t *fin;
|
|
ip_t *ip;
|
|
nat_t *nat;
|
|
ftpinfo_t *ftp;
|
|
int rv;
|
|
{
|
|
int mlen, len, off, inc, i, sel, sel2, ok, ackoff, seqoff;
|
|
u_32_t thseq, thack;
|
|
char *rptr, *wptr;
|
|
ap_session_t *aps;
|
|
ftpside_t *f, *t;
|
|
tcphdr_t *tcp;
|
|
mb_t *m;
|
|
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
off = fin->fin_hlen + (tcp->th_off << 2);
|
|
#if SOLARIS && defined(_KERNEL)
|
|
m = fin->fin_qfm;
|
|
#else
|
|
m = *((mb_t **)fin->fin_mp);
|
|
#endif
|
|
|
|
#ifndef _KERNEL
|
|
mlen = mbuflen(m);
|
|
#else
|
|
# if SOLARIS
|
|
mlen = msgdsize(m);
|
|
# else
|
|
mlen = mbufchainlen(m);
|
|
# endif
|
|
#endif
|
|
mlen -= off;
|
|
|
|
aps = nat->nat_aps;
|
|
t = &ftp->ftp_side[1 - rv];
|
|
f = &ftp->ftp_side[rv];
|
|
thseq = ntohl(tcp->th_seq);
|
|
thack = ntohl(tcp->th_ack);
|
|
|
|
sel = aps->aps_sel[1 - rv];
|
|
sel2 = aps->aps_sel[rv];
|
|
if (rv == 0) {
|
|
seqoff = aps->aps_seqoff[sel];
|
|
if (aps->aps_seqmin[sel] > seqoff + thseq)
|
|
seqoff = aps->aps_seqoff[!sel];
|
|
ackoff = aps->aps_ackoff[sel2];
|
|
if (aps->aps_ackmin[sel2] > ackoff + thack)
|
|
ackoff = aps->aps_ackoff[!sel2];
|
|
} else {
|
|
#if PROXY_DEBUG
|
|
printf("seqoff %d thseq %x ackmin %x\n", seqoff, thseq,
|
|
aps->aps_ackmin[sel]);
|
|
#endif
|
|
seqoff = aps->aps_ackoff[sel];
|
|
if (aps->aps_ackmin[sel] > seqoff + thseq)
|
|
seqoff = aps->aps_ackoff[!sel];
|
|
|
|
#if PROXY_DEBUG
|
|
printf("ackoff %d thack %x seqmin %x\n", ackoff, thack,
|
|
aps->aps_seqmin[sel2]);
|
|
#endif
|
|
ackoff = aps->aps_seqoff[sel2];
|
|
if (ackoff > 0) {
|
|
if (aps->aps_seqmin[sel2] > ackoff + thack)
|
|
ackoff = aps->aps_seqoff[!sel2];
|
|
} else {
|
|
if (aps->aps_seqmin[sel2] > thack)
|
|
ackoff = aps->aps_seqoff[!sel2];
|
|
}
|
|
}
|
|
#if PROXY_DEBUG
|
|
printf("%s: %x seq %x/%d ack %x/%d len %d\n", rv ? "IN" : "OUT",
|
|
tcp->th_flags, thseq, seqoff, thack, ackoff, mlen);
|
|
printf("sel %d seqmin %x/%x offset %d/%d\n", sel,
|
|
aps->aps_seqmin[sel], aps->aps_seqmin[sel2],
|
|
aps->aps_seqoff[sel], aps->aps_seqoff[sel2]);
|
|
printf("sel %d ackmin %x/%x offset %d/%d\n", sel2,
|
|
aps->aps_ackmin[sel], aps->aps_ackmin[sel2],
|
|
aps->aps_ackoff[sel], aps->aps_ackoff[sel2]);
|
|
#endif
|
|
|
|
/*
|
|
* XXX - Ideally, this packet should get dropped because we now know
|
|
* that it is out of order (and there is no real danger in doing so
|
|
* apart from causing packets to go through here ordered).
|
|
*/
|
|
#if PROXY_DEBUG
|
|
printf("rv %d t:seq[0] %x seq[1] %x %d/%d\n",
|
|
rv, t->ftps_seq[0], t->ftps_seq[1], seqoff, ackoff);
|
|
#endif
|
|
|
|
ok = 0;
|
|
if (t->ftps_seq[0] == 0)
|
|
t->ftps_seq[0] = thack, ok = 1;
|
|
else {
|
|
if (ackoff == 0) {
|
|
if (t->ftps_seq[0] == thack)
|
|
ok = 1;
|
|
else if (t->ftps_seq[1] == thack) {
|
|
t->ftps_seq[0] = thack;
|
|
ok = 1;
|
|
}
|
|
} else {
|
|
if (t->ftps_seq[0] + ackoff == thack)
|
|
ok = 1;
|
|
else if (t->ftps_seq[0] == thack + ackoff)
|
|
ok = 1;
|
|
else if (t->ftps_seq[1] + ackoff == thack) {
|
|
t->ftps_seq[0] = thack - ackoff;
|
|
ok = 1;
|
|
} else if (t->ftps_seq[1] == thack + ackoff) {
|
|
t->ftps_seq[0] = thack - ackoff;
|
|
ok = 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
#if PROXY_DEBUG
|
|
if (!ok)
|
|
printf("not ok\n");
|
|
#endif
|
|
|
|
if (!mlen) {
|
|
if (t->ftps_seq[0] + ackoff != thack)
|
|
return APR_ERR(1);
|
|
|
|
#if PROXY_DEBUG
|
|
printf("f:seq[0] %x seq[1] %x\n", f->ftps_seq[0], f->ftps_seq[1]);
|
|
#endif
|
|
if (tcp->th_flags & TH_FIN) {
|
|
if (thseq + seqoff == f->ftps_seq[0] + 1 ||
|
|
f->ftps_seq[0] + seqoff + 1 == thseq ||
|
|
thseq + seqoff == f->ftps_seq[0] ||
|
|
thseq == f->ftps_seq[0] + seqoff)
|
|
;
|
|
else {
|
|
#if PROXY_DEBUG
|
|
printf("FIN: thseq %x seqoff %d ftps_seq %x\n",
|
|
thseq, seqoff, f->ftps_seq[0]);
|
|
#endif
|
|
return APR_ERR(1);
|
|
}
|
|
}
|
|
f->ftps_len = 0;
|
|
return 0;
|
|
}
|
|
|
|
ok = 0;
|
|
if (thseq == f->ftps_seq[0] || thseq == f->ftps_seq[1])
|
|
ok = 1;
|
|
/*
|
|
* Retransmitted data packet.
|
|
*/
|
|
else if (thseq + mlen == f->ftps_seq[0] ||
|
|
thseq + mlen == f->ftps_seq[1])
|
|
ok = 1;
|
|
if (ok == 0) {
|
|
inc = thseq - f->ftps_seq[0];
|
|
#if PROXY_DEBUG
|
|
printf("inc %d sel %d rv %d\n", inc, sel, rv);
|
|
printf("th_seq %x ftps_seq %x/%x\n", thseq, f->ftps_seq[0],
|
|
f->ftps_seq[1]);
|
|
printf("ackmin %x ackoff %d\n", aps->aps_ackmin[sel],
|
|
aps->aps_ackoff[sel]);
|
|
printf("seqmin %x seqoff %d\n", aps->aps_seqmin[sel],
|
|
aps->aps_seqoff[sel]);
|
|
#endif
|
|
|
|
return APR_ERR(1);
|
|
}
|
|
|
|
inc = 0;
|
|
rptr = f->ftps_rptr;
|
|
wptr = f->ftps_wptr;
|
|
f->ftps_seq[0] = thseq;
|
|
f->ftps_seq[1] = f->ftps_seq[0] + mlen;
|
|
f->ftps_len = mlen;
|
|
|
|
while (mlen > 0) {
|
|
len = MIN(mlen, FTP_BUFSZ / 2);
|
|
|
|
#if !defined(_KERNEL)
|
|
bcopy((char *)m + off, wptr, len);
|
|
#else
|
|
# if SOLARIS
|
|
copyout_mblk(m, off, len, wptr);
|
|
# else
|
|
m_copydata(m, off, len, wptr);
|
|
# endif
|
|
#endif
|
|
mlen -= len;
|
|
off += len;
|
|
wptr += len;
|
|
f->ftps_wptr = wptr;
|
|
if (f->ftps_junk == 2)
|
|
f->ftps_junk = ippr_ftp_valid(rv, rptr, wptr - rptr);
|
|
|
|
while ((f->ftps_junk == 0) && (wptr > rptr)) {
|
|
f->ftps_junk = ippr_ftp_valid(rv, rptr, wptr - rptr);
|
|
if (f->ftps_junk == 0) {
|
|
f->ftps_cmds++;
|
|
len = wptr - rptr;
|
|
f->ftps_rptr = rptr;
|
|
if (rv)
|
|
inc += ippr_ftp_server(fin, ip, nat,
|
|
ftp, len);
|
|
else
|
|
inc += ippr_ftp_client(fin, ip, nat,
|
|
ftp, len);
|
|
rptr = f->ftps_rptr;
|
|
wptr = f->ftps_wptr;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Off to a bad start so lets just forget about using the
|
|
* ftp proxy for this connection.
|
|
*/
|
|
if ((f->ftps_cmds == 0) && (f->ftps_junk == 1)) {
|
|
/* f->ftps_seq[1] += inc; */
|
|
return APR_ERR(2);
|
|
}
|
|
|
|
while ((f->ftps_junk == 1) && (rptr < wptr)) {
|
|
while ((rptr < wptr) && (*rptr != '\r'))
|
|
rptr++;
|
|
|
|
if (*rptr == '\r') {
|
|
if (rptr + 1 < wptr) {
|
|
if (*(rptr + 1) == '\n') {
|
|
rptr += 2;
|
|
f->ftps_junk = 0;
|
|
} else
|
|
rptr++;
|
|
} else
|
|
break;
|
|
}
|
|
}
|
|
f->ftps_rptr = rptr;
|
|
|
|
if (rptr == wptr) {
|
|
rptr = wptr = f->ftps_buf;
|
|
} else {
|
|
if ((wptr > f->ftps_buf + FTP_BUFSZ / 2)) {
|
|
i = wptr - rptr;
|
|
if ((rptr == f->ftps_buf) ||
|
|
(wptr - rptr > FTP_BUFSZ / 2)) {
|
|
f->ftps_junk = 1;
|
|
rptr = wptr = f->ftps_buf;
|
|
} else {
|
|
bcopy(rptr, f->ftps_buf, i);
|
|
wptr = f->ftps_buf + i;
|
|
rptr = f->ftps_buf;
|
|
}
|
|
}
|
|
f->ftps_rptr = rptr;
|
|
f->ftps_wptr = wptr;
|
|
}
|
|
}
|
|
|
|
/* f->ftps_seq[1] += inc; */
|
|
if (tcp->th_flags & TH_FIN)
|
|
f->ftps_seq[1]++;
|
|
#ifndef _KERNEL
|
|
mlen = mbuflen(m);
|
|
#else
|
|
# if SOLARIS
|
|
mlen = msgdsize(m);
|
|
# else
|
|
mlen = mbufchainlen(m);
|
|
# endif
|
|
#endif
|
|
off = fin->fin_hlen + (tcp->th_off << 2);
|
|
mlen -= off;
|
|
#if PROXY_DEBUG
|
|
printf("ftps_seq[1] = %x inc %d len %d\n", f->ftps_seq[1], inc, mlen);
|
|
#endif
|
|
|
|
f->ftps_rptr = rptr;
|
|
f->ftps_wptr = wptr;
|
|
return APR_INC(inc);
|
|
}
|
|
|
|
|
|
int ippr_ftp_out(fin, ip, aps, nat)
|
|
fr_info_t *fin;
|
|
ip_t *ip;
|
|
ap_session_t *aps;
|
|
nat_t *nat;
|
|
{
|
|
ftpinfo_t *ftp;
|
|
|
|
ftp = aps->aps_data;
|
|
if (ftp == NULL)
|
|
return 0;
|
|
return ippr_ftp_process(fin, ip, nat, ftp, 0);
|
|
}
|
|
|
|
|
|
int ippr_ftp_in(fin, ip, aps, nat)
|
|
fr_info_t *fin;
|
|
ip_t *ip;
|
|
ap_session_t *aps;
|
|
nat_t *nat;
|
|
{
|
|
ftpinfo_t *ftp;
|
|
|
|
ftp = aps->aps_data;
|
|
if (ftp == NULL)
|
|
return 0;
|
|
return ippr_ftp_process(fin, ip, nat, ftp, 1);
|
|
}
|
|
|
|
|
|
/*
|
|
* ippr_ftp_atoi - implement a version of atoi which processes numbers in
|
|
* pairs separated by commas (which are expected to be in the range 0 - 255),
|
|
* returning a 16 bit number combining either side of the , as the MSB and
|
|
* LSB.
|
|
*/
|
|
u_short ippr_ftp_atoi(ptr)
|
|
char **ptr;
|
|
{
|
|
register char *s = *ptr, c;
|
|
register u_char i = 0, j = 0;
|
|
|
|
while ((c = *s++) && isdigit(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (c != ',') {
|
|
*ptr = NULL;
|
|
return 0;
|
|
}
|
|
while ((c = *s++) && isdigit(c)) {
|
|
j *= 10;
|
|
j += c - '0';
|
|
}
|
|
*ptr = s;
|
|
i &= 0xff;
|
|
j &= 0xff;
|
|
return (i << 8) | j;
|
|
}
|