Home | History | Annotate | Download | only in slirp
      1 /*
      2  * Copyright (c) 1982, 1986, 1993
      3  *	The Regents of the University of California.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. Neither the name of the University nor the names of its contributors
     14  *    may be used to endorse or promote products derived from this software
     15  *    without specific prior written permission.
     16  *
     17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     27  * SUCH DAMAGE.
     28  *
     29  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
     30  * ip.h,v 1.3 1994/08/21 05:27:30 paul Exp
     31  */
     32 
     33 #ifndef _IP_H_
     34 #define _IP_H_
     35 
     36 #ifdef HOST_WORDS_BIGENDIAN
     37 # ifndef NTOHL
     38 #  define NTOHL(d)
     39 # endif
     40 # ifndef NTOHS
     41 #  define NTOHS(d)
     42 # endif
     43 # ifndef HTONL
     44 #  define HTONL(d)
     45 # endif
     46 # ifndef HTONS
     47 #  define HTONS(d)
     48 # endif
     49 #else
     50 # ifndef NTOHL
     51 #  define NTOHL(d) ((d) = ntohl((d)))
     52 # endif
     53 # ifndef NTOHS
     54 #  define NTOHS(d) ((d) = ntohs((u_int16_t)(d)))
     55 # endif
     56 # ifndef HTONL
     57 #  define HTONL(d) ((d) = htonl((d)))
     58 # endif
     59 # ifndef HTONS
     60 #  define HTONS(d) ((d) = htons((u_int16_t)(d)))
     61 # endif
     62 #endif
     63 
     64 typedef u_int32_t n_long;                 /* long as received from the net */
     65 
     66 /*
     67  * Definitions for internet protocol version 4.
     68  * Per RFC 791, September 1981.
     69  */
     70 #define	IPVERSION	4
     71 
     72 /*
     73  * Structure of an internet header, naked of options.
     74  */
     75 struct ip {
     76 #ifdef HOST_WORDS_BIGENDIAN
     77 	u_int ip_v:4,			/* version */
     78 		ip_hl:4;		/* header length */
     79 #else
     80 	u_int ip_hl:4,		/* header length */
     81 		ip_v:4;			/* version */
     82 #endif
     83 	u_int8_t ip_tos;			/* type of service */
     84 	u_int16_t	ip_len;			/* total length */
     85 	u_int16_t	ip_id;			/* identification */
     86 	u_int16_t	ip_off;			/* fragment offset field */
     87 #define	IP_DF 0x4000			/* don't fragment flag */
     88 #define	IP_MF 0x2000			/* more fragments flag */
     89 #define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
     90 	u_int8_t ip_ttl;			/* time to live */
     91 	u_int8_t ip_p;			/* protocol */
     92 	u_int16_t	ip_sum;			/* checksum */
     93 	struct	in_addr ip_src,ip_dst;	/* source and dest address */
     94 };
     95 
     96 #define	IP_MAXPACKET	65535		/* maximum packet size */
     97 
     98 /*
     99  * Definitions for IP type of service (ip_tos)
    100  */
    101 #define	IPTOS_LOWDELAY		0x10
    102 #define	IPTOS_THROUGHPUT	0x08
    103 #define	IPTOS_RELIABILITY	0x04
    104 
    105 /*
    106  * Definitions for options.
    107  */
    108 #define	IPOPT_COPIED(o)		((o)&0x80)
    109 #define	IPOPT_CLASS(o)		((o)&0x60)
    110 #define	IPOPT_NUMBER(o)		((o)&0x1f)
    111 
    112 #define	IPOPT_CONTROL		0x00
    113 #define	IPOPT_RESERVED1		0x20
    114 #define	IPOPT_DEBMEAS		0x40
    115 #define	IPOPT_RESERVED2		0x60
    116 
    117 #define	IPOPT_EOL		0		/* end of option list */
    118 #define	IPOPT_NOP		1		/* no operation */
    119 
    120 #define	IPOPT_RR		7		/* record packet route */
    121 #define	IPOPT_TS		68		/* timestamp */
    122 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
    123 #define	IPOPT_LSRR		131		/* loose source route */
    124 #define	IPOPT_SATID		136		/* satnet id */
    125 #define	IPOPT_SSRR		137		/* strict source route */
    126 
    127 /*
    128  * Offsets to fields in options other than EOL and NOP.
    129  */
    130 #define	IPOPT_OPTVAL		0		/* option ID */
    131 #define	IPOPT_OLEN		1		/* option length */
    132 #define IPOPT_OFFSET		2		/* offset within option */
    133 #define	IPOPT_MINOFF		4		/* min value of above */
    134 
    135 /*
    136  * Time stamp option structure.
    137  */
    138 struct	ip_timestamp {
    139 	u_int8_t	ipt_code;		/* IPOPT_TS */
    140 	u_int8_t	ipt_len;		/* size of structure (variable) */
    141 	u_int8_t	ipt_ptr;		/* index of current entry */
    142 #ifdef HOST_WORDS_BIGENDIAN
    143 	u_int	ipt_oflw:4,		/* overflow counter */
    144 		ipt_flg:4;		/* flags, see below */
    145 #else
    146 	u_int	ipt_flg:4,		/* flags, see below */
    147 		ipt_oflw:4;		/* overflow counter */
    148 #endif
    149 	union ipt_timestamp {
    150 		n_long	ipt_time[1];
    151 		struct	ipt_ta {
    152 			struct in_addr ipt_addr;
    153 			n_long ipt_time;
    154 		} ipt_ta[1];
    155 	} ipt_timestamp;
    156 };
    157 
    158 /* flag bits for ipt_flg */
    159 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
    160 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
    161 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
    162 
    163 /* bits for security (not byte swapped) */
    164 #define	IPOPT_SECUR_UNCLASS	0x0000
    165 #define	IPOPT_SECUR_CONFID	0xf135
    166 #define	IPOPT_SECUR_EFTO	0x789a
    167 #define	IPOPT_SECUR_MMMM	0xbc4d
    168 #define	IPOPT_SECUR_RESTR	0xaf13
    169 #define	IPOPT_SECUR_SECRET	0xd788
    170 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
    171 
    172 /*
    173  * Internet implementation parameters.
    174  */
    175 #define	MAXTTL		255		/* maximum time to live (seconds) */
    176 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
    177 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
    178 #define	IPTTLDEC	1		/* subtracted when forwarding */
    179 
    180 #define	IP_MSS		576		/* default maximum segment size */
    181 
    182 #if SIZEOF_CHAR_P == 4
    183 struct mbuf_ptr {
    184 	struct mbuf *mptr;
    185 	uint32_t dummy;
    186 };
    187 #else
    188 struct mbuf_ptr {
    189 	struct mbuf *mptr;
    190 };
    191 #endif
    192 struct qlink {
    193 	void *next, *prev;
    194 };
    195 
    196 /*
    197  * Overlay for ip header used by other protocols (tcp, udp).
    198  */
    199 struct ipovly {
    200 	struct mbuf_ptr ih_mbuf;	/* backpointer to mbuf */
    201 	u_int8_t	ih_x1;			/* (unused) */
    202 	u_int8_t	ih_pr;			/* protocol */
    203 	u_int16_t	ih_len;			/* protocol length */
    204 	struct	in_addr ih_src;		/* source internet address */
    205 	struct	in_addr ih_dst;		/* destination internet address */
    206 } __attribute__((packed));
    207 
    208 /*
    209  * Ip reassembly queue structure.  Each fragment
    210  * being reassembled is attached to one of these structures.
    211  * They are timed out after ipq_ttl drops to 0, and may also
    212  * be reclaimed if memory becomes tight.
    213  * size 28 bytes
    214  */
    215 struct ipq {
    216         struct qlink frag_link;			/* to ip headers of fragments */
    217 	struct qlink ip_link;				/* to other reass headers */
    218 	u_int8_t	ipq_ttl;		/* time for reass q to live */
    219 	u_int8_t	ipq_p;			/* protocol of this fragment */
    220 	u_int16_t	ipq_id;			/* sequence id for reassembly */
    221 	struct	in_addr ipq_src,ipq_dst;
    222 };
    223 
    224 /*
    225  * Ip header, when holding a fragment.
    226  *
    227  * Note: ipf_link must be at same offset as frag_link above
    228  */
    229 struct	ipasfrag {
    230 	struct qlink ipf_link;
    231 	struct ip ipf_ip;
    232 };
    233 
    234 #define ipf_off      ipf_ip.ip_off
    235 #define ipf_tos      ipf_ip.ip_tos
    236 #define ipf_len      ipf_ip.ip_len
    237 #define ipf_next     ipf_link.next
    238 #define ipf_prev     ipf_link.prev
    239 
    240 /*
    241  * Structure stored in mbuf in inpcb.ip_options
    242  * and passed to ip_output when ip options are in use.
    243  * The actual length of the options (including ipopt_dst)
    244  * is in m_len.
    245  */
    246 #define MAX_IPOPTLEN	40
    247 
    248 struct ipoption {
    249 	struct	in_addr ipopt_dst;	/* first-hop dst if source routed */
    250 	int8_t	ipopt_list[MAX_IPOPTLEN];	/* options proper */
    251 };
    252 
    253 #ifdef LOG_ENABLED
    254 /*
    255  * Structure attached to inpcb.ip_moptions and
    256  * passed to ip_output when IP multicast options are in use.
    257  */
    258 
    259 struct	ipstat {
    260 	u_long	ips_total;		/* total packets received */
    261 	u_long	ips_badsum;		/* checksum bad */
    262 	u_long	ips_tooshort;		/* packet too short */
    263 	u_long	ips_toosmall;		/* not enough data */
    264 	u_long	ips_badhlen;		/* ip header length < data size */
    265 	u_long	ips_badlen;		/* ip length < ip header length */
    266 	u_long	ips_fragments;		/* fragments received */
    267 	u_long	ips_fragdropped;	/* frags dropped (dups, out of space) */
    268 	u_long	ips_fragtimeout;	/* fragments timed out */
    269 	u_long	ips_forward;		/* packets forwarded */
    270 	u_long	ips_cantforward;	/* packets rcvd for unreachable dest */
    271 	u_long	ips_redirectsent;	/* packets forwarded on same net */
    272 	u_long	ips_noproto;		/* unknown or unsupported protocol */
    273 	u_long	ips_delivered;		/* datagrams delivered to upper level*/
    274 	u_long	ips_localout;		/* total ip packets generated here */
    275 	u_long	ips_odropped;		/* lost packets due to nobufs, etc. */
    276 	u_long	ips_reassembled;	/* total packets reassembled ok */
    277 	u_long	ips_fragmented;		/* datagrams successfully fragmented */
    278 	u_long	ips_ofragments;		/* output fragments created */
    279 	u_long	ips_cantfrag;		/* don't fragment flag was set, etc. */
    280 	u_long	ips_badoptions;		/* error in option processing */
    281 	u_long	ips_noroute;		/* packets discarded due to no route */
    282 	u_long	ips_badvers;		/* ip version != 4 */
    283 	u_long	ips_rawout;		/* total raw ip packets generated */
    284 	u_long	ips_unaligned;		/* times the ip packet was not aligned */
    285 };
    286 
    287 extern struct	ipstat	ipstat;
    288 #endif
    289 
    290 extern struct	ipq	ipq;			/* ip reass. queue */
    291 extern u_int16_t	ip_id;				/* ip packet ctr, for ids */
    292 
    293 #endif
    294