2113 lines
50 KiB
C
2113 lines
50 KiB
C
/* $NetBSD: ip_ftp_pxy.c,v 1.4 2012/07/30 19:27:46 pgoyette Exp $ */
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/*
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* Copyright (C) 2012 by Darren Reed.
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*
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* See the IPFILTER.LICENCE file for details on licencing.
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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 1.1.1.2 2012/07/22 13:45:18 darrenr Exp
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(1, "$NetBSD: ip_ftp_pxy.c,v 1.4 2012/07/30 19:27:46 pgoyette Exp $");
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#define IPF_FTP_PROXY
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#define IPF_MINPORTLEN 18
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#define IPF_MINEPRTLEN 20
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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_MIN229LEN 47
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#define IPF_MAX229LEN 51
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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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#define FTPXY_JUNK_OK 0
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#define FTPXY_JUNK_BAD 1 /* Ignore all commands for this connection */
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#define FTPXY_JUNK_EOL 2 /* consume the rest of this line only */
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#define FTPXY_JUNK_CONT 3 /* Saerching for next numeric */
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/*
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* Values for FTP commands. Numerics cover 0-999
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*/
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#define FTPXY_C_PASV 1000
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#define FTPXY_C_PORT 1001
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#define FTPXY_C_EPSV 1002
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#define FTPXY_C_EPRT 1003
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typedef struct ipf_ftp_softc_s {
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int ipf_p_ftp_pasvonly;
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/* Do not require logins before transfers */
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int ipf_p_ftp_insecure;
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int ipf_p_ftp_pasvrdr;
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/* PASV must be last command prior to 227 */
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int ipf_p_ftp_forcepasv;
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int ipf_p_ftp_debug;
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int ipf_p_ftp_single_xfer;
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void *ipf_p_ftp_tune;
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} ipf_ftp_softc_t;
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void ipf_p_ftp_main_load(void);
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void ipf_p_ftp_main_unload(void);
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void *ipf_p_ftp_soft_create(ipf_main_softc_t *);
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void ipf_p_ftp_soft_destroy(ipf_main_softc_t *, void *);
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int ipf_p_ftp_client(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_complete(char *, size_t);
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int ipf_p_ftp_in(void *, fr_info_t *, ap_session_t *, nat_t *);
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int ipf_p_ftp_new(void *, fr_info_t *, ap_session_t *, nat_t *);
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void ipf_p_ftp_del(ipf_main_softc_t *, ap_session_t *);
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int ipf_p_ftp_out(void *, fr_info_t *, ap_session_t *, nat_t *);
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int ipf_p_ftp_pasv(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_epsv(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_port(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_process(ipf_ftp_softc_t *, fr_info_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_server(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_valid(ipf_ftp_softc_t *, ftpinfo_t *, int, char *, size_t);
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int ipf_p_ftp_server_valid(ipf_ftp_softc_t *, ftpside_t *, char *,
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size_t);
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int ipf_p_ftp_client_valid(ipf_ftp_softc_t *, ftpside_t *, char *,
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size_t);
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u_short ipf_p_ftp_atoi(char **);
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int ipf_p_ftp_pasvreply(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, u_int, char *, char *);
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int ipf_p_ftp_eprt(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_eprt4(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_eprt6(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int);
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int ipf_p_ftp_addport(ipf_ftp_softc_t *, fr_info_t *, ip_t *, nat_t *,
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ftpinfo_t *, int, int, int);
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void ipf_p_ftp_setpending(ipf_main_softc_t *, ftpinfo_t *);
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/*
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* Debug levels
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*/
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#define DEBUG_SECURITY 0x01
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#define DEBUG_ERROR 0x02
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#define DEBUG_INFO 0x04
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#define DEBUG_PARSE_ERR 0x08
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#define DEBUG_PARSE_INFO 0x10
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#define DEBUG_PARSE 0x20
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static int ipf_p_ftp_proxy_init = 0;
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static frentry_t ftppxyfr;
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static ipftuneable_t ipf_ftp_tuneables[] = {
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{ { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_debug) },
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"ftp_debug", 0, 0x7f,
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stsizeof(ipf_ftp_softc_t, ipf_p_ftp_debug),
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0, NULL, NULL },
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{ { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_pasvonly) },
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"ftp_pasvonly", 0, 1,
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stsizeof(ipf_ftp_softc_t, ipf_p_ftp_pasvonly),
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0, NULL, NULL },
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{ { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_insecure) },
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"ftp_insecure", 0, 1,
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stsizeof(ipf_ftp_softc_t, ipf_p_ftp_insecure),
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0, NULL, NULL },
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{ { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_pasvrdr) },
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"ftp_pasvrdr", 0, 1,
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stsizeof(ipf_ftp_softc_t, ipf_p_ftp_pasvrdr),
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0, NULL, NULL },
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{ { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_forcepasv) },
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"ftp_forcepasv", 0, 1,
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stsizeof(ipf_ftp_softc_t, ipf_p_ftp_forcepasv),
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0, NULL, NULL },
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{ { (void *)offsetof(ipf_ftp_softc_t, ipf_p_ftp_single_xfer) },
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"ftp_single_xfer", 0, 1,
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stsizeof(ipf_ftp_softc_t, ipf_p_ftp_single_xfer),
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0, NULL, NULL },
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{ { NULL }, NULL, 0, 0, 0, 0, NULL, NULL }
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};
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void
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ipf_p_ftp_main_load(void)
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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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MUTEX_INIT(&ftppxyfr.fr_lock, "FTP Proxy Mutex");
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ipf_p_ftp_proxy_init = 1;
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}
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void
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ipf_p_ftp_main_unload(void)
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{
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if (ipf_p_ftp_proxy_init == 1) {
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MUTEX_DESTROY(&ftppxyfr.fr_lock);
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ipf_p_ftp_proxy_init = 0;
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}
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}
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/*
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* Initialize local structures.
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*/
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void *
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ipf_p_ftp_soft_create(ipf_main_softc_t *softc)
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{
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ipf_ftp_softc_t *softf;
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KMALLOC(softf, ipf_ftp_softc_t *);
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if (softf == NULL)
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return NULL;
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bzero((char *)softf, sizeof(*softf));
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#if defined(_KERNEL)
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softf->ipf_p_ftp_debug = 0;
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#else
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softf->ipf_p_ftp_debug = DEBUG_PARSE_ERR;
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#endif
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softf->ipf_p_ftp_forcepasv = 1;
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softf->ipf_p_ftp_tune = ipf_tune_array_copy(softf,
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sizeof(ipf_ftp_tuneables),
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ipf_ftp_tuneables);
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if (softf->ipf_p_ftp_tune == NULL) {
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ipf_p_ftp_soft_destroy(softc, softf);
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return NULL;
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}
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if (ipf_tune_array_link(softc, softf->ipf_p_ftp_tune) == -1) {
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ipf_p_ftp_soft_destroy(softc, softf);
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return NULL;
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}
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return softf;
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}
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void
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ipf_p_ftp_soft_destroy(ipf_main_softc_t *softc, void *arg)
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{
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ipf_ftp_softc_t *softf = arg;
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if (softf->ipf_p_ftp_tune != NULL) {
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ipf_tune_array_unlink(softc, softf->ipf_p_ftp_tune);
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KFREES(softf->ipf_p_ftp_tune, sizeof(ipf_ftp_tuneables));
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softf->ipf_p_ftp_tune = NULL;
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}
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KFREE(softf);
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}
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int
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ipf_p_ftp_new(void *arg, fr_info_t *fin, ap_session_t *aps, 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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nat = nat; /* LINT */
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aps->aps_data = ftp;
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aps->aps_psiz = sizeof(ftpinfo_t);
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aps->aps_sport = htons(fin->fin_sport);
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aps->aps_dport = htons(fin->fin_dport);
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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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ftp->ftp_incok = 0;
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return 0;
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}
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void
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ipf_p_ftp_setpending(ipf_main_softc_t *softc, ftpinfo_t *ftp)
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{
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if (ftp->ftp_pendnat != NULL)
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ipf_nat_setpending(softc, ftp->ftp_pendnat);
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if (ftp->ftp_pendstate != NULL) {
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READ_ENTER(&softc->ipf_state);
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ipf_state_setpending(softc, ftp->ftp_pendstate);
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RWLOCK_EXIT(&softc->ipf_state);
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}
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}
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void
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ipf_p_ftp_del(ipf_main_softc_t *softc, ap_session_t *aps)
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{
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ftpinfo_t *ftp;
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ftp = aps->aps_data;
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if (ftp != NULL)
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ipf_p_ftp_setpending(softc, ftp);
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}
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int
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ipf_p_ftp_port(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
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ftpinfo_t *ftp, int dlen)
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{
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char newbuf[IPF_FTPBUFSZ], *s;
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u_int a1, a2, a3, a4;
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u_short a5, a6, sp;
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size_t nlen, olen;
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tcphdr_t *tcp;
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int inc, off;
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ftpside_t *f;
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mb_t *m;
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m = fin->fin_m;
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f = &ftp->ftp_side[0];
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tcp = (tcphdr_t *)fin->fin_dp;
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off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
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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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DT3(ftp_PORT_error_dlen, nat_t *, nat, ftpside_t *, f,
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u_int, dlen);
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if (softf->ipf_p_ftp_debug & DEBUG_PARSE)
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printf("ipf_p_ftp_port:dlen(%d) < IPF_MINPORTLEN\n",
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dlen);
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return 0;
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}
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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 = ipf_p_ftp_atoi(&s);
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if (s == NULL) {
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DT2(ftp_PORT_error_atoi_1, nat_t *, nat, ftpside_t *, f);
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if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
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printf("ipf_p_ftp_port:ipf_p_ftp_atoi(%d) failed\n", 1);
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return 0;
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}
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a2 = ipf_p_ftp_atoi(&s);
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if (s == NULL) {
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DT2(ftp_PORT_error_atoi_2, nat_t *, nat, ftpside_t *, f);
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if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
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printf("ipf_p_ftp_port:ipf_p_ftp_atoi(%d) failed\n", 2);
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return 0;
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}
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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 (((nat->nat_dir == NAT_OUTBOUND) &&
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(a1 != ntohl(nat->nat_osrcaddr))) ||
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((nat->nat_dir == NAT_INBOUND) &&
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(a1 != ntohl(nat->nat_nsrcaddr)))) {
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DT3(ftp_PORT_error_address, nat_t *, nat, ftpside_t *, f,
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u_int, a1);
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if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
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printf("ipf_p_ftp_port:%s != nat->nat_inip\n", "a1");
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return APR_ERR(1);
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}
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a5 = ipf_p_ftp_atoi(&s);
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if (s == NULL) {
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DT2(ftp_PORT_error_atoi_3, nat_t *, nat, ftpside_t *, f);
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if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
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printf("ipf_p_ftp_port:ipf_p_ftp_atoi(%d) failed\n", 3);
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return 0;
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}
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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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DT2(ftp_PORT_error_no_crlf, nat_t *, nat, ftpside_t *, f);
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if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
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printf("ipf_p_ftp_port:missing %s\n", "cr-lf");
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return 0;
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}
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s += 2;
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a6 = a5 & 0xff;
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/*
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* Calculate the source port. Verification of > 1024 is in
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* ipf_p_ftp_addport.
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*/
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a5 >>= 8;
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a5 &= 0xff;
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sp = a5 << 8 | a6;
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/*
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* Calculate new address parts for PORT command
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*/
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if (nat->nat_dir == NAT_INBOUND)
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a1 = ntohl(nat->nat_ndstaddr);
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else
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a1 = ntohl(ip->ip_src.s_addr);
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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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#if defined(SNPRINTF) && defined(_KERNEL)
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SNPRINTF(newbuf, sizeof(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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#else
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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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#endif
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nlen = strlen(newbuf);
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inc = nlen - olen;
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if ((inc + fin->fin_plen) > 65535) {
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DT3(ftp_PORT_error_inc, nat_t *, nat, ftpside_t *, f,
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int, inc);
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if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
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printf("ipf_p_ftp_port:inc(%d) + ip->ip_len > 65535\n",
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inc);
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return 0;
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}
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#if !defined(_KERNEL)
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M_ADJ(m, inc);
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#else
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/*
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* m_adj takes care of pkthdr.len, if required and treats inc<0 to
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* mean remove -len bytes from the end of the packet.
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* The mbuf chain will be extended if necessary by m_copyback().
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*/
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if (inc < 0)
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M_ADJ(m, inc);
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#endif /* !defined(_KERNEL) */
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COPYBACK(m, off, nlen, newbuf);
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fin->fin_flx |= FI_DOCKSUM;
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if (inc != 0) {
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fin->fin_plen += inc;
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ip->ip_len = htons(fin->fin_plen);
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fin->fin_dlen += inc;
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}
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f->ftps_cmd = FTPXY_C_PORT;
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return ipf_p_ftp_addport(softf, fin, ip, nat, ftp, dlen, sp, inc);
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}
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int
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ipf_p_ftp_addport(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
|
|
ftpinfo_t *ftp, int dlen, int nport, int inc)
|
|
{
|
|
tcphdr_t tcph, *tcp2 = &tcph;
|
|
ipf_main_softc_t *softc;
|
|
ipf_nat_softc_t *softn;
|
|
int direction;
|
|
fr_info_t fi;
|
|
ipnat_t *ipn;
|
|
nat_t *nat2;
|
|
u_short sp;
|
|
int flags;
|
|
|
|
softc = fin->fin_main_soft;
|
|
softn = softc->ipf_nat_soft;
|
|
|
|
if ((ftp->ftp_pendnat != NULL) || (ftp->ftp_pendstate != NULL)) {
|
|
if (softf->ipf_p_ftp_single_xfer != 0) {
|
|
DT2(ftp_PORT_error_add_active, nat_t *, nat,
|
|
ftpinfo_t *, ftp);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_addport:xfer active %p/%p\n",
|
|
ftp->ftp_pendnat, ftp->ftp_pendstate);
|
|
return 0;
|
|
}
|
|
ipf_p_ftp_setpending(softc, ftp);
|
|
}
|
|
|
|
/*
|
|
* Add skeleton NAT entry for connection which will come back the
|
|
* other way.
|
|
*/
|
|
sp = nport;
|
|
/*
|
|
* Don't allow the PORT command to specify a port < 1024 due to
|
|
* security risks.
|
|
*/
|
|
if (sp < 1024) {
|
|
DT3(ftp_PORT_error_port, nat_t *, nat, ftpinfo_t *, ftp,
|
|
u_int, sp);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_SECURITY)
|
|
printf("ipf_p_ftp_addport:sp(%d) < 1024\n", sp);
|
|
return 0;
|
|
}
|
|
/*
|
|
* The server may not make the connection back from port 20, but
|
|
* it is the most likely so use it here to check for a conflicting
|
|
* mapping.
|
|
*/
|
|
bcopy((char *)fin, (char *)&fi, sizeof(fi));
|
|
fi.fin_flx |= FI_IGNORE;
|
|
fi.fin_data[0] = sp;
|
|
fi.fin_data[1] = fin->fin_data[1] - 1;
|
|
fi.fin_src6 = nat->nat_ndst6;
|
|
fi.fin_dst6 = nat->nat_nsrc6;
|
|
|
|
if (nat->nat_v[0] == 6) {
|
|
#ifndef USE_INET6
|
|
return APR_INC(inc);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Add skeleton NAT entry for connection which will come back the
|
|
* other way.
|
|
*/
|
|
if (nat->nat_v[0] == 6) {
|
|
#ifdef USE_INET6
|
|
if (nat->nat_dir == NAT_OUTBOUND) {
|
|
nat2 = ipf_nat6_outlookup(&fi, IPN_TCP|NAT_SEARCH,
|
|
nat->nat_pr[1],
|
|
&nat->nat_osrc6.in6,
|
|
&nat->nat_odst6.in6);
|
|
} else {
|
|
nat2 = ipf_nat6_inlookup(&fi, IPN_TCP|NAT_SEARCH,
|
|
nat->nat_pr[0],
|
|
&nat->nat_odst6.in6,
|
|
&nat->nat_osrc6.in6);
|
|
}
|
|
#endif
|
|
} else {
|
|
if (nat->nat_dir == NAT_OUTBOUND) {
|
|
nat2 = ipf_nat_outlookup(&fi, IPN_TCP|NAT_SEARCH,
|
|
nat->nat_pr[1],
|
|
nat->nat_osrcip,
|
|
nat->nat_odstip);
|
|
} else {
|
|
nat2 = ipf_nat_inlookup(&fi, IPN_TCP|NAT_SEARCH,
|
|
nat->nat_pr[0],
|
|
nat->nat_odstip,
|
|
nat->nat_osrcip);
|
|
}
|
|
}
|
|
if (nat2 != NULL)
|
|
return APR_INC(inc);
|
|
|
|
ipn = ipf_proxy_rule_rev(nat);
|
|
if (ipn == NULL)
|
|
return APR_ERR(1);
|
|
ipn->in_use = 0;
|
|
|
|
fi.fin_fr = &ftppxyfr;
|
|
fi.fin_dp = (char *)tcp2;
|
|
fi.fin_dlen = sizeof(*tcp2);
|
|
fi.fin_plen = fi.fin_hlen + sizeof(*tcp2);
|
|
fi.fin_flx &= FI_LOWTTL|FI_FRAG|FI_TCPUDP|FI_OPTIONS|FI_IGNORE;
|
|
fi.fin_data[1] = sp;
|
|
fi.fin_data[0] = 0;
|
|
|
|
bzero((char *)tcp2, sizeof(*tcp2));
|
|
tcp2->th_sport = 0;
|
|
tcp2->th_dport = htons(sp);
|
|
|
|
tcp2->th_win = htons(8192);
|
|
TCP_OFF_A(tcp2, 5);
|
|
tcp2->th_flags = TH_SYN;
|
|
|
|
if (nat->nat_dir == NAT_INBOUND) {
|
|
fi.fin_out = 1;
|
|
direction = NAT_OUTBOUND;
|
|
} else {
|
|
fi.fin_out = 0;
|
|
direction = NAT_INBOUND;
|
|
}
|
|
flags = SI_W_SPORT|NAT_SLAVE|IPN_TCP;
|
|
|
|
MUTEX_ENTER(&softn->ipf_nat_new);
|
|
if (nat->nat_v[0] == 6) {
|
|
#ifdef USE_INET6
|
|
nat2 = ipf_nat6_add(&fi, ipn, &ftp->ftp_pendnat, flags,
|
|
direction);
|
|
#endif
|
|
} else {
|
|
nat2 = ipf_nat_add(&fi, ipn, &ftp->ftp_pendnat, flags,
|
|
direction);
|
|
}
|
|
MUTEX_EXIT(&softn->ipf_nat_new);
|
|
|
|
if (nat2 == NULL) {
|
|
KFREES(ipn, ipn->in_size);
|
|
return APR_ERR(1);
|
|
}
|
|
|
|
(void) ipf_nat_proto(&fi, nat2, IPN_TCP);
|
|
MUTEX_ENTER(&nat2->nat_lock);
|
|
ipf_nat_update(&fi, nat2);
|
|
MUTEX_EXIT(&nat2->nat_lock);
|
|
fi.fin_ifp = NULL;
|
|
if (nat2->nat_dir == NAT_INBOUND)
|
|
fi.fin_dst6 = nat->nat_osrc6;
|
|
if (ipf_state_add(softc, &fi, (ipstate_t **)&ftp->ftp_pendstate,
|
|
SI_W_SPORT) != 0)
|
|
ipf_nat_setpending(softc, nat2);
|
|
|
|
return APR_INC(inc);
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_client(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
|
|
ftpinfo_t *ftp, int dlen)
|
|
{
|
|
char *rptr, *wptr, cmd[6], c;
|
|
ftpside_t *f;
|
|
int inc, i;
|
|
|
|
inc = 0;
|
|
f = &ftp->ftp_side[0];
|
|
rptr = f->ftps_rptr;
|
|
wptr = f->ftps_wptr;
|
|
|
|
for (i = 0; (i < 5) && (i < dlen); i++) {
|
|
c = rptr[i];
|
|
if (ISALPHA(c)) {
|
|
cmd[i] = TOUPPER(c);
|
|
} else {
|
|
cmd[i] = c;
|
|
}
|
|
}
|
|
cmd[i] = '\0';
|
|
|
|
ftp->ftp_incok = 0;
|
|
DT2(ftp_client_command, char [], cmd, int, ftp->ftp_passok);
|
|
if (!strncmp(cmd, "USER ", 5) || !strncmp(cmd, "XAUT ", 5)) {
|
|
if (ftp->ftp_passok == FTPXY_ADOK_1 ||
|
|
ftp->ftp_passok == FTPXY_AUOK_1) {
|
|
ftp->ftp_passok = FTPXY_USER_2;
|
|
ftp->ftp_incok = 1;
|
|
} else {
|
|
ftp->ftp_passok = FTPXY_USER_1;
|
|
ftp->ftp_incok = 1;
|
|
}
|
|
} else if (!strncmp(cmd, "AUTH ", 5)) {
|
|
ftp->ftp_passok = FTPXY_AUTH_1;
|
|
ftp->ftp_incok = 1;
|
|
} else if (!strncmp(cmd, "PASS ", 5)) {
|
|
if (ftp->ftp_passok == FTPXY_USOK_1) {
|
|
ftp->ftp_passok = FTPXY_PASS_1;
|
|
ftp->ftp_incok = 1;
|
|
} else if (ftp->ftp_passok == FTPXY_USOK_2) {
|
|
ftp->ftp_passok = FTPXY_PASS_2;
|
|
ftp->ftp_incok = 1;
|
|
}
|
|
} else if ((ftp->ftp_passok == FTPXY_AUOK_1) &&
|
|
!strncmp(cmd, "ADAT ", 5)) {
|
|
ftp->ftp_passok = FTPXY_ADAT_1;
|
|
ftp->ftp_incok = 1;
|
|
} else if ((ftp->ftp_passok == FTPXY_PAOK_1 ||
|
|
ftp->ftp_passok == FTPXY_PAOK_2) &&
|
|
!strncmp(cmd, "ACCT ", 5)) {
|
|
ftp->ftp_passok = FTPXY_ACCT_1;
|
|
ftp->ftp_incok = 1;
|
|
} else if ((ftp->ftp_passok == FTPXY_GO) &&
|
|
!softf->ipf_p_ftp_pasvonly &&
|
|
!strncmp(cmd, "PORT ", 5)) {
|
|
inc = ipf_p_ftp_port(softf, fin, ip, nat, ftp, dlen);
|
|
} else if ((ftp->ftp_passok == FTPXY_GO) &&
|
|
!softf->ipf_p_ftp_pasvonly &&
|
|
!strncmp(cmd, "EPRT ", 5)) {
|
|
inc = ipf_p_ftp_eprt(softf, fin, ip, nat, ftp, dlen);
|
|
} else if (softf->ipf_p_ftp_insecure &&
|
|
!softf->ipf_p_ftp_pasvonly &&
|
|
!strncmp(cmd, "PORT ", 5)) {
|
|
inc = ipf_p_ftp_port(softf, fin, ip, nat, ftp, dlen);
|
|
}
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE)
|
|
printf("ipf_p_ftp_client: cmd[%s] passok %d incok %d inc %d\n",
|
|
cmd, ftp->ftp_passok, ftp->ftp_incok, inc);
|
|
|
|
DT2(ftp_client_passok, char *, cmd, int, ftp->ftp_passok);
|
|
while ((*rptr++ != '\n') && (rptr < wptr))
|
|
;
|
|
f->ftps_rptr = rptr;
|
|
return inc;
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_pasv(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
|
|
ftpinfo_t *ftp, int dlen)
|
|
{
|
|
u_int a1, a2, a3, a4, data_ip;
|
|
char newbuf[IPF_FTPBUFSZ];
|
|
const char *brackets[2];
|
|
u_short a5, a6;
|
|
ftpside_t *f;
|
|
char *s;
|
|
|
|
if ((softf->ipf_p_ftp_forcepasv != 0) &&
|
|
(ftp->ftp_side[0].ftps_cmd != FTPXY_C_PASV)) {
|
|
DT2(ftp_PASV_error_state, nat_t *, nat, ftpinfo_t *, ftp);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_pasv:ftps_cmd(%d) != FTPXY_C_PASV\n",
|
|
ftp->ftp_side[0].ftps_cmd);
|
|
return 0;
|
|
}
|
|
|
|
f = &ftp->ftp_side[1];
|
|
|
|
#define PASV_REPLEN 24
|
|
/*
|
|
* Check for PASV reply message.
|
|
*/
|
|
if (dlen < IPF_MIN227LEN) {
|
|
DT3(ftp_PASV_error_short, nat_t *, nat, ftpinfo_t *, ftp,
|
|
int, dlen);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_pasv:dlen(%d) < IPF_MIN227LEN\n",
|
|
dlen);
|
|
return 0;
|
|
} else if (strncmp(f->ftps_rptr,
|
|
"227 Entering Passive Mod", PASV_REPLEN)) {
|
|
DT2(ftp_PASV_error_string, nat_t *, nat, ftpinfo_t *, ftp);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_pasv:%d reply wrong\n", 227);
|
|
return 0;
|
|
}
|
|
|
|
brackets[0] = "";
|
|
brackets[1] = "";
|
|
/*
|
|
* Skip the PASV reply + space
|
|
*/
|
|
s = f->ftps_rptr + PASV_REPLEN;
|
|
while (*s && !ISDIGIT(*s)) {
|
|
if (*s == '(') {
|
|
brackets[0] = "(";
|
|
brackets[1] = ")";
|
|
}
|
|
s++;
|
|
}
|
|
|
|
/*
|
|
* Pick out the address components, two at a time.
|
|
*/
|
|
a1 = ipf_p_ftp_atoi(&s);
|
|
if (s == NULL) {
|
|
DT2(ftp_PASV_error_atoi_1, nat_t *, nat, ftpside_t *, f);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_pasv:ipf_p_ftp_atoi(%d) failed\n", 1);
|
|
return 0;
|
|
}
|
|
a2 = ipf_p_ftp_atoi(&s);
|
|
if (s == NULL) {
|
|
DT2(ftp_PASV_error_atoi_2, nat_t *, nat, ftpside_t *, f);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_pasv:ipf_p_ftp_atoi(%d) failed\n", 2);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* check that IP address in the PASV reply is the same as the
|
|
* sender of the command - prevents using PASV for port scanning.
|
|
*/
|
|
a1 <<= 16;
|
|
a1 |= a2;
|
|
|
|
if (((nat->nat_dir == NAT_INBOUND) &&
|
|
(a1 != ntohl(nat->nat_ndstaddr))) ||
|
|
((nat->nat_dir == NAT_OUTBOUND) &&
|
|
(a1 != ntohl(nat->nat_odstaddr)))) {
|
|
DT3(ftp_PASV_error_address, nat_t *, nat, ftpside_t *, f,
|
|
u_int, a1);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_pasv:%s != nat->nat_oip\n", "a1");
|
|
return 0;
|
|
}
|
|
|
|
a5 = ipf_p_ftp_atoi(&s);
|
|
if (s == NULL) {
|
|
DT2(ftp_PASV_error_atoi_3, nat_t *, nat, ftpside_t *, f);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_pasv:ipf_p_ftp_atoi(%d) failed\n", 3);
|
|
return 0;
|
|
}
|
|
|
|
if (*s == ')')
|
|
s++;
|
|
if (*s == '.')
|
|
s++;
|
|
if (*s == '\n')
|
|
s--;
|
|
/*
|
|
* check for CR-LF at the end.
|
|
*/
|
|
if ((*s != '\r') || (*(s + 1) != '\n')) {
|
|
DT(pasv_missing_crlf);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_pasv:missing %s", "cr-lf\n");
|
|
return 0;
|
|
}
|
|
s += 2;
|
|
|
|
a6 = a5 & 0xff;
|
|
a5 >>= 8;
|
|
/*
|
|
* Calculate new address parts for 227 reply
|
|
*/
|
|
if (nat->nat_dir == NAT_INBOUND) {
|
|
data_ip = nat->nat_odstaddr;
|
|
a1 = ntohl(data_ip);
|
|
} else
|
|
data_ip = htonl(a1);
|
|
|
|
a2 = (a1 >> 16) & 0xff;
|
|
a3 = (a1 >> 8) & 0xff;
|
|
a4 = a1 & 0xff;
|
|
a1 >>= 24;
|
|
|
|
#if defined(SNPRINTF) && defined(_KERNEL)
|
|
SNPRINTF(newbuf, sizeof(newbuf), "%s %s%u,%u,%u,%u,%u,%u%s\r\n",
|
|
"227 Entering Passive Mode", brackets[0], a1, a2, a3, a4,
|
|
a5, a6, brackets[1]);
|
|
#else
|
|
(void) sprintf(newbuf, "%s %s%u,%u,%u,%u,%u,%u%s\r\n",
|
|
"227 Entering Passive Mode", brackets[0], a1, a2, a3, a4,
|
|
a5, a6, brackets[1]);
|
|
#endif
|
|
return ipf_p_ftp_pasvreply(softf, fin, ip, nat, ftp, (a5 << 8 | a6),
|
|
newbuf, s);
|
|
}
|
|
|
|
int
|
|
ipf_p_ftp_pasvreply(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip,
|
|
nat_t *nat, ftpinfo_t *ftp, u_int port, char *newmsg, char *s)
|
|
{
|
|
int inc, off, nflags;
|
|
tcphdr_t *tcp, tcph, *tcp2;
|
|
ipf_main_softc_t *softc;
|
|
ipf_nat_softc_t *softn;
|
|
size_t nlen, olen;
|
|
#ifdef USE_INET6
|
|
ip6_t *ip6;
|
|
#endif
|
|
ipnat_t *ipn;
|
|
fr_info_t fi;
|
|
ftpside_t *f;
|
|
nat_t *nat2 = NULL;
|
|
mb_t *m;
|
|
|
|
softc = fin->fin_main_soft;
|
|
softn = softc->ipf_nat_soft;
|
|
|
|
if ((ftp->ftp_pendnat != NULL) || (ftp->ftp_pendstate != NULL))
|
|
ipf_p_ftp_setpending(softc, ftp);
|
|
|
|
m = fin->fin_m;
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
|
|
|
|
tcp2 = &tcph;
|
|
inc = 0;
|
|
|
|
f = &ftp->ftp_side[1];
|
|
olen = s - f->ftps_rptr;
|
|
nlen = strlen(newmsg);
|
|
inc = nlen - olen;
|
|
if ((inc + fin->fin_plen) > 65535) {
|
|
DT3(ftp_PASV_error_inc, nat_t *, nat, ftpside_t *, f,
|
|
int, inc);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_pasv:inc(%d) + ip->ip_len > 65535\n",
|
|
inc);
|
|
return 0;
|
|
}
|
|
|
|
ipn = ipf_proxy_rule_fwd(nat);
|
|
if (ipn == NULL)
|
|
return APR_ERR(1);
|
|
ipn->in_use = 0;
|
|
|
|
/*
|
|
* Add skeleton NAT entry for connection which will come back the
|
|
* other way.
|
|
*/
|
|
bzero((char *)tcp2, sizeof(*tcp2));
|
|
bcopy((char *)fin, (char *)&fi, sizeof(fi));
|
|
fi.fin_flx |= FI_IGNORE;
|
|
fi.fin_data[0] = 0;
|
|
fi.fin_data[1] = port;
|
|
nflags = IPN_TCP|SI_W_SPORT;
|
|
|
|
fi.fin_fr = &ftppxyfr;
|
|
fi.fin_dp = (char *)tcp2;
|
|
fi.fin_out = 1 - fin->fin_out;
|
|
fi.fin_dlen = sizeof(*tcp2);
|
|
fi.fin_src6 = nat->nat_osrc6;
|
|
fi.fin_dst6 = nat->nat_odst6;
|
|
fi.fin_plen = fi.fin_hlen + sizeof(*tcp);
|
|
fi.fin_flx &= FI_LOWTTL|FI_FRAG|FI_TCPUDP|FI_OPTIONS|FI_IGNORE;
|
|
|
|
TCP_OFF_A(tcp2, 5);
|
|
tcp2->th_flags = TH_SYN;
|
|
tcp2->th_win = htons(8192);
|
|
tcp2->th_dport = htons(port);
|
|
|
|
MUTEX_ENTER(&softn->ipf_nat_new);
|
|
if (nat->nat_v[0] == 6) {
|
|
#ifdef USE_INET6
|
|
nat2 = ipf_nat6_add(&fi, ipn, &ftp->ftp_pendnat,
|
|
nflags, nat->nat_dir);
|
|
#endif
|
|
} else {
|
|
nat2 = ipf_nat_add(&fi, ipn, &ftp->ftp_pendnat,
|
|
nflags, nat->nat_dir);
|
|
}
|
|
MUTEX_EXIT(&softn->ipf_nat_new);
|
|
|
|
if (nat2 == NULL) {
|
|
KFREES(ipn, ipn->in_size);
|
|
return APR_ERR(1);
|
|
}
|
|
|
|
(void) ipf_nat_proto(&fi, nat2, IPN_TCP);
|
|
MUTEX_ENTER(&nat2->nat_lock);
|
|
ipf_nat_update(&fi, nat2);
|
|
MUTEX_EXIT(&nat2->nat_lock);
|
|
fi.fin_ifp = NULL;
|
|
if (nat->nat_dir == NAT_INBOUND) {
|
|
if (nat->nat_v[0] == 6) {
|
|
#ifdef USE_INET6
|
|
fi.fin_dst6 = nat->nat_ndst6;
|
|
#endif
|
|
} else {
|
|
fi.fin_daddr = nat->nat_ndstaddr;
|
|
}
|
|
}
|
|
if (ipf_state_add(softc, &fi, (ipstate_t **)&ftp->ftp_pendstate,
|
|
SI_W_SPORT) != 0)
|
|
ipf_nat_setpending(softc, nat2);
|
|
|
|
#if !defined(_KERNEL)
|
|
M_ADJ(m, inc);
|
|
#else
|
|
/*
|
|
* m_adj takes care of pkthdr.len, if required and treats inc<0 to
|
|
* mean remove -len bytes from the end of the packet.
|
|
* The mbuf chain will be extended if necessary by m_copyback().
|
|
*/
|
|
if (inc < 0)
|
|
M_ADJ(m, inc);
|
|
#endif /* !defined(_KERNEL) */
|
|
COPYBACK(m, off, nlen, newmsg);
|
|
fin->fin_flx |= FI_DOCKSUM;
|
|
|
|
if (inc != 0) {
|
|
fin->fin_plen += inc;
|
|
fin->fin_dlen += inc;
|
|
if (nat->nat_v[0] == 6) {
|
|
#ifdef USE_INET6
|
|
ip6 = (ip6_t *)fin->fin_ip;
|
|
u_short len = ntohs(ip6->ip6_plen) + inc;
|
|
ip6->ip6_plen = htons(len);
|
|
#endif
|
|
} else {
|
|
ip->ip_len = htons(fin->fin_plen);
|
|
}
|
|
}
|
|
|
|
return APR_INC(inc);
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_server(ipf_ftp_softc_t *softf, 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;
|
|
|
|
DT2(ftp_server_response, char *, rptr, int, ftp->ftp_passok);
|
|
if (*rptr == ' ')
|
|
goto server_cmd_ok;
|
|
if (!ISDIGIT(*rptr) || !ISDIGIT(*(rptr + 1)) || !ISDIGIT(*(rptr + 2)))
|
|
return 0;
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE)
|
|
printf("ipf_p_ftp_server_1: cmd[%4.4s] passok %d\n",
|
|
rptr, ftp->ftp_passok);
|
|
if (ftp->ftp_passok == FTPXY_GO) {
|
|
if (!strncmp(rptr, "227 ", 4))
|
|
inc = ipf_p_ftp_pasv(softf, fin, ip, nat, ftp, dlen);
|
|
else if (!strncmp(rptr, "229 ", 4))
|
|
inc = ipf_p_ftp_epsv(softf, fin, ip, nat, ftp, dlen);
|
|
else if (strncmp(rptr, "200", 3)) {
|
|
/*
|
|
* 200 is returned for a successful command.
|
|
*/
|
|
;
|
|
}
|
|
} else if (softf->ipf_p_ftp_insecure && !strncmp(rptr, "227 ", 4)) {
|
|
inc = ipf_p_ftp_pasv(softf, fin, ip, nat, ftp, dlen);
|
|
} else if (softf->ipf_p_ftp_insecure && !strncmp(rptr, "229 ", 4)) {
|
|
inc = ipf_p_ftp_epsv(softf, fin, ip, nat, ftp, 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;
|
|
server_cmd_ok:
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE)
|
|
printf("ipf_p_ftp_server_2: cmd[%4.4s] passok %d\n",
|
|
rptr, ftp->ftp_passok);
|
|
DT3(ftp_server_passok, char *,rptr, int, ftp->ftp_incok,
|
|
int, ftp->ftp_passok);
|
|
|
|
while ((*rptr++ != '\n') && (rptr < wptr))
|
|
;
|
|
f->ftps_rptr = rptr;
|
|
return inc;
|
|
}
|
|
|
|
|
|
/*
|
|
* 0 FTPXY_JUNK_OK
|
|
* 1 FTPXY_JUNK_BAD
|
|
* 2 FTPXY_JUNK_EOL
|
|
* 3 FTPXY_JUNK_CONT
|
|
*
|
|
* Look to see if the buffer starts with something which we recognise as
|
|
* being the correct syntax for the FTP protocol.
|
|
*/
|
|
int
|
|
ipf_p_ftp_client_valid(ipf_ftp_softc_t *softf, ftpside_t *ftps, char *buf,
|
|
size_t len)
|
|
{
|
|
register char *s, c, pc;
|
|
register size_t i = len;
|
|
char cmd[5];
|
|
|
|
s = buf;
|
|
|
|
if (ftps->ftps_junk == FTPXY_JUNK_BAD)
|
|
return FTPXY_JUNK_BAD;
|
|
|
|
if (i < 5) {
|
|
DT1(client_valid, int, i);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_client_valid:i(%d) < 5\n", (int)i);
|
|
return 2;
|
|
}
|
|
|
|
i--;
|
|
c = *s++;
|
|
|
|
if (ISALPHA(c)) {
|
|
cmd[0] = TOUPPER(c);
|
|
c = *s++;
|
|
i--;
|
|
if (ISALPHA(c)) {
|
|
cmd[1] = TOUPPER(c);
|
|
c = *s++;
|
|
i--;
|
|
if (ISALPHA(c)) {
|
|
cmd[2] = TOUPPER(c);
|
|
c = *s++;
|
|
i--;
|
|
if (ISALPHA(c)) {
|
|
cmd[3] = TOUPPER(c);
|
|
c = *s++;
|
|
i--;
|
|
if ((c != ' ') && (c != '\r'))
|
|
goto bad_client_command;
|
|
} else if ((c != ' ') && (c != '\r'))
|
|
goto bad_client_command;
|
|
} else
|
|
goto bad_client_command;
|
|
} else
|
|
goto bad_client_command;
|
|
} else {
|
|
bad_client_command:
|
|
DT4(client_junk, int, len, int, i, int, c, char *, buf);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("%s:bad:junk %d len %d/%d c 0x%x buf [%*.*s]\n",
|
|
"ipf_p_ftp_client_valid",
|
|
ftps->ftps_junk, (int)len, (int)i, c,
|
|
(int)len, (int)len, buf);
|
|
return FTPXY_JUNK_BAD;
|
|
}
|
|
|
|
for (; i; i--) {
|
|
pc = c;
|
|
c = *s++;
|
|
if ((pc == '\r') && (c == '\n')) {
|
|
cmd[4] = '\0';
|
|
if (!strcmp(cmd, "PASV")) {
|
|
ftps->ftps_cmd = FTPXY_C_PASV;
|
|
} else if (!strcmp(cmd, "EPSV")) {
|
|
ftps->ftps_cmd = FTPXY_C_EPSV;
|
|
} else {
|
|
ftps->ftps_cmd = 0;
|
|
}
|
|
return 0;
|
|
}
|
|
}
|
|
#if !defined(_KERNEL)
|
|
printf("ipf_p_ftp_client_valid:junk after cmd[%*.*s]\n",
|
|
(int)len, (int)len, buf);
|
|
#endif
|
|
return FTPXY_JUNK_EOL;
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_server_valid(ipf_ftp_softc_t *softf, ftpside_t *ftps, char *buf,
|
|
size_t len)
|
|
{
|
|
register char *s, c, pc;
|
|
register size_t i = len;
|
|
int cmd;
|
|
|
|
s = buf;
|
|
cmd = 0;
|
|
|
|
if (ftps->ftps_junk == FTPXY_JUNK_BAD)
|
|
return FTPXY_JUNK_BAD;
|
|
|
|
if (i < 5) {
|
|
DT1(server_valid, int, i);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_servert_valid:i(%d) < 5\n", (int)i);
|
|
return 2;
|
|
}
|
|
|
|
c = *s++;
|
|
i--;
|
|
if (c == ' ') {
|
|
cmd = -1;
|
|
goto search_eol;
|
|
}
|
|
|
|
if (ISDIGIT(c)) {
|
|
cmd = (c - '0') * 100;
|
|
c = *s++;
|
|
i--;
|
|
if (ISDIGIT(c)) {
|
|
cmd += (c - '0') * 10;
|
|
c = *s++;
|
|
i--;
|
|
if (ISDIGIT(c)) {
|
|
cmd += (c - '0');
|
|
c = *s++;
|
|
i--;
|
|
if ((c != '-') && (c != ' '))
|
|
goto bad_server_command;
|
|
if (c == '-')
|
|
return FTPXY_JUNK_CONT;
|
|
} else
|
|
goto bad_server_command;
|
|
} else
|
|
goto bad_server_command;
|
|
} else {
|
|
bad_server_command:
|
|
DT4(server_junk, int len, buf, int, i, int, c, char *, buf);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_INFO)
|
|
printf("%s:bad:junk %d len %d/%d c 0x%x buf [%*.*s]\n",
|
|
"ipf_p_ftp_server_valid",
|
|
ftps->ftps_junk, (int)len, (int)i,
|
|
c, (int)len, (int)len, buf);
|
|
if (ftps->ftps_junk == FTPXY_JUNK_CONT)
|
|
return FTPXY_JUNK_CONT;
|
|
return FTPXY_JUNK_BAD;
|
|
}
|
|
search_eol:
|
|
for (; i; i--) {
|
|
pc = c;
|
|
c = *s++;
|
|
if ((pc == '\r') && (c == '\n')) {
|
|
if (cmd == -1) {
|
|
if (ftps->ftps_junk == FTPXY_JUNK_CONT)
|
|
return FTPXY_JUNK_CONT;
|
|
} else {
|
|
ftps->ftps_cmd = cmd;
|
|
}
|
|
return FTPXY_JUNK_OK;
|
|
}
|
|
}
|
|
|
|
DT2(junk_eol, int, len, char *, buf);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_INFO)
|
|
printf("ipf_p_ftp_server_valid:junk after cmd[%*.*s]\n",
|
|
(int)len, (int)len, buf);
|
|
return FTPXY_JUNK_EOL;
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_valid(ipf_ftp_softc_t *softf, ftpinfo_t *ftp, int side, char *buf,
|
|
size_t len)
|
|
{
|
|
ftpside_t *ftps;
|
|
int ret;
|
|
|
|
ftps = &ftp->ftp_side[side];
|
|
|
|
if (side == 0)
|
|
ret = ipf_p_ftp_client_valid(softf, ftps, buf, len);
|
|
else
|
|
ret = ipf_p_ftp_server_valid(softf, ftps, buf, len);
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
* For map rules, the following applies:
|
|
* rv == 0 for outbound processing,
|
|
* rv == 1 for inbound processing.
|
|
* For rdr rules, the following applies:
|
|
* rv == 0 for inbound processing,
|
|
* rv == 1 for outbound processing.
|
|
*/
|
|
int
|
|
ipf_p_ftp_process(ipf_ftp_softc_t *softf, fr_info_t *fin, nat_t *nat,
|
|
ftpinfo_t *ftp, int rv)
|
|
{
|
|
int mlen, len, off, inc, i, sel, sel2, ok, ackoff, seqoff, retry;
|
|
char *rptr, *wptr, *s;
|
|
u_32_t thseq, thack;
|
|
ap_session_t *aps;
|
|
ftpside_t *f, *t;
|
|
tcphdr_t *tcp;
|
|
ip_t *ip;
|
|
mb_t *m;
|
|
|
|
m = fin->fin_m;
|
|
ip = fin->fin_ip;
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
|
|
|
|
f = &ftp->ftp_side[rv];
|
|
t = &ftp->ftp_side[1 - rv];
|
|
thseq = ntohl(tcp->th_seq);
|
|
thack = ntohl(tcp->th_ack);
|
|
#ifdef __sgi
|
|
mlen = fin->fin_plen - off;
|
|
#else
|
|
mlen = MSGDSIZE(m) - off;
|
|
#endif
|
|
|
|
DT3(process_debug, tcphdr_t *, tcp, int, off, int, mlen);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_INFO)
|
|
printf("ipf_p_ftp_process: %d:%d,%d, mlen %d flags %x\n",
|
|
fin->fin_out, fin->fin_sport, fin->fin_dport,
|
|
mlen, tcp->th_flags);
|
|
|
|
if ((mlen == 0) && ((tcp->th_flags & TH_OPENING) == TH_OPENING)) {
|
|
f->ftps_seq[0] = thseq + 1;
|
|
t->ftps_seq[0] = thack;
|
|
return 0;
|
|
} else if (mlen < 0) {
|
|
return 0;
|
|
}
|
|
|
|
aps = nat->nat_aps;
|
|
|
|
sel = aps->aps_sel[1 - rv];
|
|
sel2 = aps->aps_sel[rv];
|
|
if (rv == 1) {
|
|
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 {
|
|
seqoff = aps->aps_ackoff[sel];
|
|
if (softf->ipf_p_ftp_debug & DEBUG_INFO)
|
|
printf("seqoff %d thseq %x ackmin %x\n", seqoff, thseq,
|
|
aps->aps_ackmin[sel]);
|
|
if (aps->aps_ackmin[sel] > seqoff + thseq)
|
|
seqoff = aps->aps_ackoff[!sel];
|
|
|
|
ackoff = aps->aps_seqoff[sel2];
|
|
if (softf->ipf_p_ftp_debug & DEBUG_INFO)
|
|
printf("ackoff %d thack %x seqmin %x\n", ackoff, thack,
|
|
aps->aps_seqmin[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 (softf->ipf_p_ftp_debug & DEBUG_INFO) {
|
|
printf("%s: %x seq %x/%d ack %x/%d len %d/%d off %d\n",
|
|
rv ? "IN" : "OUT", tcp->th_flags, thseq, seqoff,
|
|
thack, ackoff, mlen, fin->fin_plen, off);
|
|
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]);
|
|
}
|
|
|
|
/*
|
|
* 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 (softf->ipf_p_ftp_debug & DEBUG_INFO) {
|
|
printf("rv %d t:seq[0] %x seq[1] %x %d/%d\n",
|
|
rv, t->ftps_seq[0], t->ftps_seq[1], seqoff, ackoff);
|
|
}
|
|
|
|
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) {
|
|
t->ftps_seq[0] = thack;
|
|
ok = 1;
|
|
} else if (t->ftps_seq[0] == thack + ackoff) {
|
|
t->ftps_seq[0] = thack + ackoff;
|
|
ok = 1;
|
|
} else if (t->ftps_seq[1] + ackoff == thack) {
|
|
t->ftps_seq[0] = thack;
|
|
ok = 1;
|
|
} else if (t->ftps_seq[1] == thack + ackoff) {
|
|
t->ftps_seq[0] = thack + ackoff;
|
|
ok = 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (softf->ipf_p_ftp_debug & DEBUG_INFO) {
|
|
if (!ok)
|
|
printf("%s ok\n", "not");
|
|
}
|
|
|
|
if (!mlen) {
|
|
if (t->ftps_seq[0] + ackoff != thack &&
|
|
t->ftps_seq[1] + ackoff != thack) {
|
|
DT3(thack, ftpside_t *t, t, int, ackoff, u_32_t, thack);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR) {
|
|
printf("%s:seq[0](%u) + (%d) != (%u)\n",
|
|
"ipf_p_ftp_process", t->ftps_seq[0],
|
|
ackoff, thack);
|
|
printf("%s:seq[0](%u) + (%d) != (%u)\n",
|
|
"ipf_p_ftp_process", t->ftps_seq[1],
|
|
ackoff, thack);
|
|
}
|
|
return APR_ERR(1);
|
|
}
|
|
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE) {
|
|
printf("ipf_p_ftp_process:f:seq[0] %x seq[1] %x\n",
|
|
f->ftps_seq[0], f->ftps_seq[1]);
|
|
}
|
|
|
|
if (tcp->th_flags & TH_FIN) {
|
|
if (thseq == f->ftps_seq[1]) {
|
|
f->ftps_seq[0] = f->ftps_seq[1] - seqoff;
|
|
f->ftps_seq[1] = thseq + 1 - seqoff;
|
|
} else {
|
|
DT2(thseq, ftpside_t *t, t, u_32_t, thseq);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR) {
|
|
printf("FIN: thseq %x seqoff %d ftps_seq %x\n",
|
|
thseq, seqoff, f->ftps_seq[0]);
|
|
}
|
|
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) {
|
|
DT3(ok_0, ftpside_t *, f, u_32_t, thseq, int, mlen);
|
|
inc = thseq - f->ftps_seq[0];
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR) {
|
|
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]);
|
|
}
|
|
|
|
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, sizeof(f->ftps_buf) - (wptr - rptr));
|
|
if (len == 0)
|
|
break;
|
|
COPYDATA(m, off, len, wptr);
|
|
mlen -= len;
|
|
off += len;
|
|
wptr += len;
|
|
|
|
whilemore:
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE)
|
|
printf("%s:len %d/%d off %d wptr %lx junk %d [%*.*s]\n",
|
|
"ipf_p_ftp_process",
|
|
len, mlen, off, (u_long)wptr, f->ftps_junk,
|
|
len, len, rptr);
|
|
|
|
f->ftps_wptr = wptr;
|
|
if (f->ftps_junk != FTPXY_JUNK_OK) {
|
|
i = f->ftps_junk;
|
|
f->ftps_junk = ipf_p_ftp_valid(softf, ftp, rv, rptr,
|
|
wptr - rptr);
|
|
DT2(junk_transit, int, i, int, f->ftps_junk);
|
|
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE)
|
|
printf("%s:junk %d -> %d\n",
|
|
"ipf_p_ftp_process", i, f->ftps_junk);
|
|
|
|
if (f->ftps_junk == FTPXY_JUNK_BAD) {
|
|
DT(buffer_full);
|
|
if (wptr - rptr == sizeof(f->ftps_buf)) {
|
|
if (softf->ipf_p_ftp_debug &
|
|
DEBUG_PARSE_INFO)
|
|
printf("%s:full buffer\n",
|
|
"ipf_p_ftp_process");
|
|
f->ftps_rptr = f->ftps_buf;
|
|
f->ftps_wptr = f->ftps_buf;
|
|
rptr = f->ftps_rptr;
|
|
wptr = f->ftps_wptr;
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
|
|
while ((f->ftps_junk == FTPXY_JUNK_OK) && (wptr > rptr)) {
|
|
len = wptr - rptr;
|
|
f->ftps_junk = ipf_p_ftp_valid(softf, ftp, rv,
|
|
rptr, len);
|
|
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE) {
|
|
printf("%s=%d len %d rv %d ptr %lx/%lx ",
|
|
"ipf_p_ftp_valid",
|
|
f->ftps_junk, len, rv, (u_long)rptr,
|
|
(u_long)wptr);
|
|
printf("buf [%*.*s]\n", len, len, rptr);
|
|
}
|
|
|
|
if (f->ftps_junk == FTPXY_JUNK_OK) {
|
|
f->ftps_cmds++;
|
|
f->ftps_rptr = rptr;
|
|
if (rv)
|
|
inc += ipf_p_ftp_server(softf, fin, ip,
|
|
nat, ftp, len);
|
|
else
|
|
inc += ipf_p_ftp_client(softf, 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 == FTPXY_JUNK_BAD)) {
|
|
/* f->ftps_seq[1] += inc; */
|
|
|
|
DT(ftp_junk_cmd);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("%s:cmds == 0 junk == 1\n",
|
|
"ipf_p_ftp_process");
|
|
return APR_ERR(2);
|
|
}
|
|
|
|
retry = 0;
|
|
if ((f->ftps_junk != FTPXY_JUNK_OK) && (rptr < wptr)) {
|
|
for (s = rptr; s < wptr; s++) {
|
|
if ((*s == '\r') && (s + 1 < wptr) &&
|
|
(*(s + 1) == '\n')) {
|
|
rptr = s + 2;
|
|
retry = 1;
|
|
if (f->ftps_junk != FTPXY_JUNK_CONT)
|
|
f->ftps_junk = FTPXY_JUNK_OK;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (rptr == wptr) {
|
|
rptr = wptr = f->ftps_buf;
|
|
} else {
|
|
/*
|
|
* Compact the buffer back to the start. The junk
|
|
* flag should already be set and because we're not
|
|
* throwing away any data, it is preserved from its
|
|
* current state.
|
|
*/
|
|
if (rptr > f->ftps_buf) {
|
|
bcopy(rptr, f->ftps_buf, wptr - rptr);
|
|
wptr -= rptr - f->ftps_buf;
|
|
rptr = f->ftps_buf;
|
|
}
|
|
}
|
|
f->ftps_rptr = rptr;
|
|
f->ftps_wptr = wptr;
|
|
if (retry)
|
|
goto whilemore;
|
|
}
|
|
|
|
/* f->ftps_seq[1] += inc; */
|
|
if (tcp->th_flags & TH_FIN)
|
|
f->ftps_seq[1]++;
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_INFO) {
|
|
#ifdef __sgi
|
|
mlen = fin->fin_plen;
|
|
#else
|
|
mlen = MSGDSIZE(m);
|
|
#endif
|
|
mlen -= off;
|
|
printf("ftps_seq[1] = %x inc %d len %d\n",
|
|
f->ftps_seq[1], inc, mlen);
|
|
}
|
|
|
|
f->ftps_rptr = rptr;
|
|
f->ftps_wptr = wptr;
|
|
return APR_INC(inc);
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_out(void *arg, fr_info_t *fin, ap_session_t *aps, nat_t *nat)
|
|
{
|
|
ipf_ftp_softc_t *softf = arg;
|
|
ftpinfo_t *ftp;
|
|
int rev;
|
|
|
|
ftp = aps->aps_data;
|
|
if (ftp == NULL)
|
|
return 0;
|
|
|
|
rev = (nat->nat_dir == NAT_OUTBOUND) ? 0 : 1;
|
|
if (ftp->ftp_side[1 - rev].ftps_ifp == NULL)
|
|
ftp->ftp_side[1 - rev].ftps_ifp = fin->fin_ifp;
|
|
|
|
return ipf_p_ftp_process(softf, fin, nat, ftp, rev);
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_in(void *arg, fr_info_t *fin, ap_session_t *aps, nat_t *nat)
|
|
{
|
|
ipf_ftp_softc_t *softf = arg;
|
|
ftpinfo_t *ftp;
|
|
int rev;
|
|
|
|
ftp = aps->aps_data;
|
|
if (ftp == NULL)
|
|
return 0;
|
|
|
|
rev = (nat->nat_dir == NAT_OUTBOUND) ? 0 : 1;
|
|
if (ftp->ftp_side[rev].ftps_ifp == NULL)
|
|
ftp->ftp_side[rev].ftps_ifp = fin->fin_ifp;
|
|
|
|
return ipf_p_ftp_process(softf, fin, nat, ftp, 1 - rev);
|
|
}
|
|
|
|
|
|
/*
|
|
* ipf_p_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
|
|
ipf_p_ftp_atoi(char **ptr)
|
|
{
|
|
register char *s = *ptr, c;
|
|
register u_char i = 0, j = 0;
|
|
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (c != ',') {
|
|
*ptr = NULL;
|
|
return 0;
|
|
}
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
j *= 10;
|
|
j += c - '0';
|
|
}
|
|
*ptr = s;
|
|
i &= 0xff;
|
|
j &= 0xff;
|
|
return (i << 8) | j;
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_eprt(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
|
|
ftpinfo_t *ftp, int dlen)
|
|
{
|
|
ftpside_t *f;
|
|
|
|
/*
|
|
* Check for client sending out EPRT message.
|
|
*/
|
|
if (dlen < IPF_MINEPRTLEN) {
|
|
DT1(epert_dlen, int, dlen);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_eprt:dlen(%d) < IPF_MINEPRTLEN\n",
|
|
dlen);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Parse the EPRT command. Format is:
|
|
* "EPRT |1|1.2.3.4|2000|" for IPv4 and
|
|
* "EPRT |2|ef00::1:2|2000|" for IPv6
|
|
*/
|
|
f = &ftp->ftp_side[0];
|
|
if (f->ftps_rptr[5] != '|')
|
|
return 0;
|
|
if (f->ftps_rptr[5] == f->ftps_rptr[7]) {
|
|
if (f->ftps_rptr[6] == '1' && nat->nat_v[0] == 4)
|
|
return ipf_p_ftp_eprt4(softf, fin, ip, nat, ftp, dlen);
|
|
#ifdef USE_INET6
|
|
if (f->ftps_rptr[6] == '2' && nat->nat_v[0] == 6)
|
|
return ipf_p_ftp_eprt6(softf, fin, ip, nat, ftp, dlen);
|
|
#endif
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_eprt4(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
|
|
ftpinfo_t *ftp, int dlen)
|
|
{
|
|
int a1, a2, a3, a4, port, olen, nlen, inc, off;
|
|
char newbuf[IPF_FTPBUFSZ];
|
|
char *s, c, delim;
|
|
u_32_t addr, i;
|
|
tcphdr_t *tcp;
|
|
ftpside_t *f;
|
|
mb_t *m;
|
|
|
|
m = fin->fin_m;
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
|
|
f = &ftp->ftp_side[0];
|
|
delim = f->ftps_rptr[5];
|
|
s = f->ftps_rptr + 8;
|
|
|
|
/*
|
|
* get the IP address.
|
|
*/
|
|
i = 0;
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (i > 255)
|
|
return 0;
|
|
if (c != '.')
|
|
return 0;
|
|
addr = (i << 24);
|
|
|
|
i = 0;
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (i > 255)
|
|
return 0;
|
|
if (c != '.')
|
|
return 0;
|
|
addr |= (addr << 16);
|
|
|
|
i = 0;
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (i > 255)
|
|
return 0;
|
|
if (c != '.')
|
|
return 0;
|
|
addr |= (addr << 8);
|
|
|
|
i = 0;
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (i > 255)
|
|
return 0;
|
|
if (c != delim)
|
|
return 0;
|
|
addr |= addr;
|
|
|
|
/*
|
|
* Get the port number
|
|
*/
|
|
i = 0;
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (i > 65535)
|
|
return 0;
|
|
if (c != delim)
|
|
return 0;
|
|
port = i;
|
|
|
|
/*
|
|
* Check for CR-LF at the end of the command string.
|
|
*/
|
|
if ((*s != '\r') || (*(s + 1) != '\n')) {
|
|
DT(eprt4_no_crlf);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_eprt4:missing %s\n", "cr-lf");
|
|
return 0;
|
|
}
|
|
s += 2;
|
|
|
|
/*
|
|
* Calculate new address parts for PORT command
|
|
*/
|
|
if (nat->nat_dir == NAT_INBOUND)
|
|
a1 = ntohl(nat->nat_odstaddr);
|
|
else
|
|
a1 = ntohl(ip->ip_src.s_addr);
|
|
a2 = (a1 >> 16) & 0xff;
|
|
a3 = (a1 >> 8) & 0xff;
|
|
a4 = a1 & 0xff;
|
|
a1 >>= 24;
|
|
olen = s - f->ftps_rptr;
|
|
/* DO NOT change this to snprintf! */
|
|
/*
|
|
* While we could force the use of | as a delimiter here, it makes
|
|
* sense to preserve whatever character is being used by the systems
|
|
* involved in the communication.
|
|
*/
|
|
#if defined(SNPRINTF) && defined(_KERNEL)
|
|
SNPRINTF(newbuf, sizeof(newbuf), "%s %c1%c%u.%u.%u.%u%c%u%c\r\n",
|
|
"EPRT", delim, delim, a1, a2, a3, a4, delim, port, delim);
|
|
#else
|
|
(void) sprintf(newbuf, "%s %c1%c%u.%u.%u.%u%c%u%c\r\n",
|
|
"EPRT", delim, delim, a1, a2, a3, a4, delim, port,
|
|
delim);
|
|
#endif
|
|
|
|
nlen = strlen(newbuf);
|
|
inc = nlen - olen;
|
|
if ((inc + fin->fin_plen) > 65535) {
|
|
DT2(eprt4_len, int, inc, int, fin->fin_plen);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_eprt4:inc(%d) + ip->ip_len > 65535\n",
|
|
inc);
|
|
return 0;
|
|
}
|
|
|
|
off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
|
|
#if !defined(_KERNEL)
|
|
M_ADJ(m, inc);
|
|
#else
|
|
if (inc < 0)
|
|
M_ADJ(m, inc);
|
|
#endif
|
|
/* the mbuf chain will be extended if necessary by m_copyback() */
|
|
COPYBACK(m, off, nlen, newbuf);
|
|
fin->fin_flx |= FI_DOCKSUM;
|
|
|
|
if (inc != 0) {
|
|
fin->fin_plen += inc;
|
|
ip->ip_len = htons(fin->fin_plen);
|
|
fin->fin_dlen += inc;
|
|
}
|
|
|
|
f->ftps_cmd = FTPXY_C_EPRT;
|
|
return ipf_p_ftp_addport(softf, fin, ip, nat, ftp, dlen, port, inc);
|
|
}
|
|
|
|
|
|
int
|
|
ipf_p_ftp_epsv(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip, nat_t *nat,
|
|
ftpinfo_t *ftp, int dlen)
|
|
{
|
|
char newbuf[IPF_FTPBUFSZ];
|
|
u_short ap = 0;
|
|
ftpside_t *f;
|
|
char *s;
|
|
|
|
if ((softf->ipf_p_ftp_forcepasv != 0) &&
|
|
(ftp->ftp_side[0].ftps_cmd != FTPXY_C_EPSV)) {
|
|
DT1(epsv_cmd, int, ftp->ftp_side[0].ftps_cmd);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_epsv:ftps_cmd(%d) != FTPXY_C_EPSV\n",
|
|
ftp->ftp_side[0].ftps_cmd);
|
|
return 0;
|
|
}
|
|
f = &ftp->ftp_side[1];
|
|
|
|
#define EPSV_REPLEN 33
|
|
/*
|
|
* Check for EPSV reply message.
|
|
*/
|
|
if (dlen < IPF_MIN229LEN) {
|
|
return (0);
|
|
} else if (strncmp(f->ftps_rptr,
|
|
"229 Entering Extended Passive Mode", EPSV_REPLEN)) {
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Skip the EPSV command + space
|
|
*/
|
|
s = f->ftps_rptr + 33;
|
|
while (*s && !ISDIGIT(*s))
|
|
s++;
|
|
|
|
/*
|
|
* As per RFC 2428, there are no addres components in the EPSV
|
|
* response. So we'll go straight to getting the port.
|
|
*/
|
|
while (*s && ISDIGIT(*s)) {
|
|
ap *= 10;
|
|
ap += *s++ - '0';
|
|
}
|
|
|
|
if (!s) {
|
|
return 0;
|
|
}
|
|
|
|
if (*s == '|')
|
|
s++;
|
|
if (*s == ')')
|
|
s++;
|
|
if (*s == '\n')
|
|
s--;
|
|
/*
|
|
* check for CR-LF at the end.
|
|
*/
|
|
if ((*s != '\r') || (*(s + 1) != '\n')) {
|
|
return 0;
|
|
}
|
|
s += 2;
|
|
|
|
#if defined(SNPRINTF) && defined(_KERNEL)
|
|
SNPRINTF(newbuf, sizeof(newbuf), "%s (|||%u|)\r\n",
|
|
"229 Entering Extended Passive Mode", ap);
|
|
#else
|
|
(void) sprintf(newbuf, "%s (|||%u|)\r\n",
|
|
"229 Entering Extended Passive Mode", ap);
|
|
#endif
|
|
|
|
return ipf_p_ftp_pasvreply(softf, fin, ip, nat, ftp, (u_int)ap,
|
|
newbuf, s);
|
|
}
|
|
|
|
#ifdef USE_INET6
|
|
int
|
|
ipf_p_ftp_eprt6(ipf_ftp_softc_t *softf, fr_info_t *fin, ip_t *ip,
|
|
nat_t *nat, ftpinfo_t *ftp, int dlen)
|
|
{
|
|
int port, olen, nlen, inc, off, left, i;
|
|
char newbuf[IPF_FTPBUFSZ];
|
|
char *s, c;
|
|
i6addr_t addr, *a6;
|
|
tcphdr_t *tcp;
|
|
ip6_t *ip6;
|
|
char delim;
|
|
u_short whole;
|
|
u_short part;
|
|
ftpside_t *f;
|
|
u_short *t;
|
|
int fwd;
|
|
mb_t *m;
|
|
u_32_t a;
|
|
|
|
m = fin->fin_m;
|
|
ip6 = (ip6_t *)ip;
|
|
f = &ftp->ftp_side[0];
|
|
s = f->ftps_rptr + 8;
|
|
f = &ftp->ftp_side[0];
|
|
delim = f->ftps_rptr[5];
|
|
tcp = (tcphdr_t *)fin->fin_dp;
|
|
off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
|
|
|
|
addr.i6[0] = 0;
|
|
addr.i6[1] = 0;
|
|
addr.i6[2] = 0;
|
|
addr.i6[3] = 0;
|
|
/*
|
|
* Parse an IPv6 address.
|
|
* Go forward until either :: or | is found. If :: is found,
|
|
* reverse direction. Direction change is performed to ease
|
|
* parsing an unknown number of 0s in the middle.
|
|
*/
|
|
whole = 0;
|
|
t = (u_short *)&addr;
|
|
fwd = 1;
|
|
for (part = 0; (c = *s) != '\0'; ) {
|
|
if (c == delim) {
|
|
*t = htons((u_short)whole);
|
|
break;
|
|
}
|
|
if (c == ':') {
|
|
*t = part;
|
|
if (fwd) {
|
|
*t = htons((u_short)whole);
|
|
t++;
|
|
} else {
|
|
*t = htons((u_short)(whole >> 16));
|
|
t--;
|
|
}
|
|
whole = 0;
|
|
if (fwd == 1 && s[1] == ':') {
|
|
while (*s && *s != '|')
|
|
s++;
|
|
if ((c = *s) != delim)
|
|
break;
|
|
t = (u_short *)&addr.i6[3];
|
|
t++;
|
|
fwd = 0;
|
|
} else if (fwd == 0 && s[-1] == ':') {
|
|
break;
|
|
}
|
|
} else {
|
|
if (c >= '0' && c <= '9') {
|
|
c -= '0';
|
|
} else if (c >= 'a' && c <= 'f') {
|
|
c -= 'a' + 10;
|
|
} else if (c >= 'A' && c <= 'F') {
|
|
c -= 'A' + 10;
|
|
}
|
|
if (fwd) {
|
|
whole <<= 8;
|
|
whole |= c;
|
|
} else {
|
|
whole >>= 8;
|
|
whole |= ((u_32_t)c) << 24;
|
|
}
|
|
}
|
|
if (fwd)
|
|
s++;
|
|
else
|
|
s--;
|
|
}
|
|
if (c != ':' && c != delim)
|
|
return 0;
|
|
|
|
while (*s != '|')
|
|
s++;
|
|
s++;
|
|
|
|
/*
|
|
* Get the port number
|
|
*/
|
|
i = 0;
|
|
while (((c = *s++) != '\0') && ISDIGIT(c)) {
|
|
i *= 10;
|
|
i += c - '0';
|
|
}
|
|
if (i > 65535)
|
|
return 0;
|
|
if (c != delim)
|
|
return 0;
|
|
port = (u_short)(i & 0xffff);
|
|
|
|
/*
|
|
* Check for CR-LF at the end of the command string.
|
|
*/
|
|
if ((*s != '\r') || (*(s + 1) != '\n')) {
|
|
DT(eprt6_no_crlf);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_PARSE_ERR)
|
|
printf("ipf_p_ftp_eprt6:missing %s\n", "cr-lf");
|
|
return 0;
|
|
}
|
|
s += 2;
|
|
|
|
/*
|
|
* Calculate new address parts for PORT command
|
|
*/
|
|
a6 = (i6addr_t *)&ip6->ip6_src;
|
|
olen = s - f->ftps_rptr;
|
|
/* DO NOT change this to snprintf! */
|
|
/*
|
|
* While we could force the use of | as a delimiter here, it makes
|
|
* sense to preserve whatever character is being used by the systems
|
|
* involved in the communication.
|
|
*/
|
|
s = newbuf;
|
|
left = sizeof(newbuf);
|
|
#if defined(SNPRINTF) && defined(_KERNEL)
|
|
SNPRINTF(newbuf, left, "EPRT %c2%c", delim, delim);
|
|
left -= strlen(s) + 1;
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[0]);
|
|
SNPRINTF(s, left, "%x:%x:", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[1]);
|
|
SNPRINTF(s, left, "%x:%x:", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[2]);
|
|
SNPRINTF(s, left, "%x:%x:", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[3]);
|
|
SNPRINTF(s, left, "%x:%x", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
sprintf(s, "|%d|\r\n", port);
|
|
#else
|
|
(void) sprintf(s, "EPRT %c2%c", delim, delim);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[0]);
|
|
sprintf(s, "%x:%x:", a >> 16, a & 0xffff);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[1]);
|
|
sprintf(s, "%x:%x:", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[2]);
|
|
sprintf(s, "%x:%x:", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
a = ntohl(a6->i6[3]);
|
|
sprintf(s, "%x:%x", a >> 16, a & 0xffff);
|
|
left -= strlen(s);
|
|
s += strlen(s);
|
|
sprintf(s, "|%d|\r\n", port);
|
|
#endif
|
|
nlen = strlen(newbuf);
|
|
inc = nlen - olen;
|
|
if ((inc + fin->fin_plen) > 65535) {
|
|
DT2(eprt6_len, int, inc, int, fin->fin_plen);
|
|
if (softf->ipf_p_ftp_debug & DEBUG_ERROR)
|
|
printf("ipf_p_ftp_eprt6:inc(%d) + ip->ip_len > 65535\n",
|
|
inc);
|
|
return 0;
|
|
}
|
|
|
|
off = (char *)tcp - (char *)ip + (TCP_OFF(tcp) << 2) + fin->fin_ipoff;
|
|
#if !defined(_KERNEL)
|
|
M_ADJ(m, inc);
|
|
#else
|
|
if (inc < 0)
|
|
M_ADJ(m, inc);
|
|
#endif
|
|
/* the mbuf chain will be extended if necessary by m_copyback() */
|
|
COPYBACK(m, off, nlen, newbuf);
|
|
fin->fin_flx |= FI_DOCKSUM;
|
|
|
|
if (inc != 0) {
|
|
fin->fin_plen += inc;
|
|
ip6->ip6_plen = htons(fin->fin_plen - fin->fin_hlen);
|
|
fin->fin_dlen += inc;
|
|
}
|
|
|
|
f->ftps_cmd = FTPXY_C_EPRT;
|
|
return ipf_p_ftp_addport(softf, fin, ip, nat, ftp, dlen, port, inc);
|
|
}
|
|
#endif /* USE_INET6 */
|