/* $OpenBSD: pfvar.h,v 1.171 2003/09/26 21:44:09 cedric Exp $ */
/*
* Copyright (c) 2001 Daniel Hartmeier
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifndef _NET_PFVAR_H_
#define _NET_PFVAR_H_
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/tree.h>
/* A packed Operating System description for fingerprinting */
typedef u_int32_t pf_osfp_t;
#define PF_OSFP_ANY ((pf_osfp_t)0)
#define PF_OSFP_UNKNOWN ((pf_osfp_t)-1)
#define PF_OSFP_NOMATCH ((pf_osfp_t)-2)
struct pf_osfp_entry {
SLIST_ENTRY(pf_osfp_entry) fp_entry;
pf_osfp_t fp_os;
int fp_enflags;
#define PF_OSFP_EXPANDED 0x001 /* expanded entry */
#define PF_OSFP_GENERIC 0x002 /* generic signature */
#define PF_OSFP_NODETAIL 0x004 /* no p0f details */
#define PF_OSFP_LEN 32
char fp_class_nm[PF_OSFP_LEN];
char fp_version_nm[PF_OSFP_LEN];
char fp_subtype_nm[PF_OSFP_LEN];
};
#define PF_OSFP_ENTRY_EQ(a, b) \
((a)->fp_os == (b)->fp_os && \
memcmp((a)->fp_class_nm, (b)->fp_class_nm, PF_OSFP_LEN) == 0 && \
memcmp((a)->fp_version_nm, (b)->fp_version_nm, PF_OSFP_LEN) == 0 && \
memcmp((a)->fp_subtype_nm, (b)->fp_subtype_nm, PF_OSFP_LEN) == 0)
/* handle pf_osfp_t packing */
#define _FP_RESERVED_BIT 1 /* For the special negative #defines */
#define _FP_UNUSED_BITS 1
#define _FP_CLASS_BITS 10 /* OS Class (Windows, Linux) */
#define _FP_VERSION_BITS 10 /* OS version (95, 98, NT, 2.4.54, 3.2) */
#define _FP_SUBTYPE_BITS 10 /* patch level (NT SP4, SP3, ECN patch) */
#define PF_OSFP_UNPACK(osfp, class, version, subtype) do { \
(class) = ((osfp) >> (_FP_VERSION_BITS+_FP_SUBTYPE_BITS)) & \
((1 << _FP_CLASS_BITS) - 1); \
(version) = ((osfp) >> _FP_SUBTYPE_BITS) & \
((1 << _FP_VERSION_BITS) - 1);\
(subtype) = (osfp) & ((1 << _FP_SUBTYPE_BITS) - 1); \
} while(0)
#define PF_OSFP_PACK(osfp, class, version, subtype) do { \
(osfp) = ((class) & ((1 << _FP_CLASS_BITS) - 1)) << (_FP_VERSION_BITS \
+ _FP_SUBTYPE_BITS); \
(osfp) |= ((version) & ((1 << _FP_VERSION_BITS) - 1)) << \
_FP_SUBTYPE_BITS; \
(osfp) |= (subtype) & ((1 << _FP_SUBTYPE_BITS) - 1); \
} while(0)
/* the fingerprint of an OSes TCP SYN packet */
typedef u_int64_t pf_tcpopts_t;
struct pf_os_fingerprint {
SLIST_HEAD(pf_osfp_enlist, pf_osfp_entry) fp_oses; /* list of matches */
pf_tcpopts_t fp_tcpopts; /* packed TCP options */
u_int16_t fp_wsize; /* TCP window size */
u_int16_t fp_psize; /* ip->ip_len */
u_int16_t fp_mss; /* TCP MSS */
u_int16_t fp_flags;
#define PF_OSFP_WSIZE_MOD 0x0001 /* Window modulus */
#define PF_OSFP_WSIZE_DC 0x0002 /* Window don't care */
#define PF_OSFP_WSIZE_MSS 0x0004 /* Window multiple of MSS */
#define PF_OSFP_WSIZE_MTU 0x0008 /* Window multiple of MTU */
#define PF_OSFP_PSIZE_MOD 0x0010 /* packet size modulus */
#define PF_OSFP_PSIZE_DC 0x0020 /* packet size don't care */
#define PF_OSFP_WSCALE 0x0040 /* TCP window scaling */
#define PF_OSFP_WSCALE_MOD 0x0080 /* TCP window scale modulus */
#define PF_OSFP_WSCALE_DC 0x0100 /* TCP window scale dont-care */
#define PF_OSFP_MSS 0x0200 /* TCP MSS */
#define PF_OSFP_MSS_MOD 0x0400 /* TCP MSS modulus */
#define PF_OSFP_MSS_DC 0x0800 /* TCP MSS dont-care */
#define PF_OSFP_DF 0x1000 /* IPv4 don't fragment bit */
#define PF_OSFP_TS0 0x2000 /* Zero timestamp */
u_int8_t fp_optcnt; /* TCP option count */
u_int8_t fp_wscale; /* TCP window scaling */
u_int8_t fp_ttl; /* IPv4 TTL */
#define PF_OSFP_MAXTTL_OFFSET 40
/* TCP options packing */
#define PF_OSFP_TCPOPT_NOP 0x0 /* TCP NOP option */
#define PF_OSFP_TCPOPT_WSCALE 0x1 /* TCP window scaling option */
#define PF_OSFP_TCPOPT_MSS 0x2 /* TCP max segment size opt */
#define PF_OSFP_TCPOPT_SACK 0x3 /* TCP SACK OK option */
#define PF_OSFP_TCPOPT_TS 0x4 /* TCP timestamp option */
#define PF_OSFP_TCPOPT_BITS 3 /* bits used by each option */
#define PF_OSFP_MAX_OPTS \
(sizeof(((struct pf_os_fingerprint *)0)->fp_tcpopts) * 8) \
/ PF_OSFP_TCPOPT_BITS
SLIST_ENTRY(pf_os_fingerprint) fp_next;
};
struct pf_osfp_ioctl {
struct pf_osfp_entry fp_os;
pf_tcpopts_t fp_tcpopts; /* packed TCP options */
u_int16_t fp_wsize; /* TCP window size */
u_int16_t fp_psize; /* ip->ip_len */
u_int16_t fp_mss; /* TCP MSS */
u_int16_t fp_flags;
u_int8_t fp_optcnt; /* TCP option count */
u_int8_t fp_wscale; /* TCP window scaling */
u_int8_t fp_ttl; /* IPv4 TTL */
int fp_getnum; /* DIOCOSFPGET number */
};
/* The fingerprint functions can be linked into userland programs (tcpdump) */
int pf_osfp_add(struct pf_osfp_ioctl *);
struct pf_osfp_enlist *
pf_osfp_fingerprint_hdr(const struct ip_hdr *, const struct tcp_hdr *);
void pf_osfp_flush(void);
int pf_osfp_get(struct pf_osfp_ioctl *);
void pf_osfp_initialize(void);
int pf_osfp_match(struct pf_osfp_enlist *, pf_osfp_t);
struct pf_os_fingerprint *
pf_osfp_validate(void);
#endif /* _NET_PFVAR_H_ */
syntax highlighted by Code2HTML, v. 0.9.1