xref: /original-bsd/sys/net/bpf.h (revision 4da674f5)
1 /*
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  *
21  * @(#) $Header: bpf.h,v 1.19 91/01/30 18:20:21 mccanne Exp $ (LBL)
22  *
23  * This code is derived from the Stanford/CMU enet packet filter,
24  * (net/enet.h) distributed with 4.3BSD Unix.
25  */
26 
27 /*
28  * Alignment macros.  BPF_WORDALIGN rounds up to the next
29  * even multiple of BPF_ALIGNMENT.
30  */
31 #define BPF_ALIGNMENT sizeof(long)
32 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
33 
34 /*
35  *  Structure for BIOCSETF.
36  */
37 struct bpf_program {
38 	u_int bf_len;
39 	struct bpf_insn *bf_insns;
40 };
41 
42 /*
43  * Struct returned by BIOCGSTATS.
44  */
45 struct bpf_stat {
46 	u_int bs_recv;		/* number of packets received */
47 	u_int bs_drop;		/* number of packets dropped */
48 };
49 
50 /*
51  * BPF ioctls
52  *
53  * The first set is for compatibility with Sun's pcc style
54  * header files.  If your using gcc, we assume that you
55  * have run fixincludes so the latter set should work.
56  */
57 #if defined(sun) && !defined(__GNUC__)
58 #define	BIOCGFLEN	_IOR(B,101, u_int)
59 #define	BIOCGBLEN	_IOR(B,102, u_int)
60 #define	BIOCSETF	_IOW(B,103, struct bpf_program)
61 #define	BIOCFLUSH	_IO(B,104)
62 #define BIOCPROMISC	_IO(B,105)
63 #define	BIOCDEVP	_IOR(B,106, struct bpf_devp)
64 #define BIOCGETIF	_IOR(B,107, struct ifreq)
65 #define BIOCSETIF	_IOW(B,108, struct ifreq)
66 #define BIOCSRTIMEOUT	_IOW(B,109, struct timeval)
67 #define BIOCGRTIMEOUT	_IOR(B,110, struct timeval)
68 #define BIOCGSTATS	_IOR(B,111, struct bpf_stat)
69 #define BIOCIMMEDIATE	_IOW(B,112, u_int)
70 #else
71 #define	BIOCGFLEN	_IOR('B',101, u_int)
72 #define	BIOCGBLEN	_IOR('B',102, u_int)
73 #define	BIOCSETF	_IOW('B',103, struct bpf_program)
74 #define	BIOCFLUSH	_IO('B',104)
75 #define BIOCPROMISC	_IO('B',105)
76 #define	BIOCDEVP	_IOR('B',106, struct bpf_devp)
77 #define BIOCGETIF	_IOR('B',107, struct ifreq)
78 #define BIOCSETIF	_IOW('B',108, struct ifreq)
79 #define BIOCSRTIMEOUT	_IOW('B',109, struct timeval)
80 #define BIOCGRTIMEOUT	_IOR('B',110, struct timeval)
81 #define BIOCGSTATS	_IOR('B',111, struct bpf_stat)
82 #define BIOCIMMEDIATE	_IOW('B',112, u_int)
83 #endif
84 
85 /*
86  * The device parameters of a network interface.
87  */
88 struct bpf_devp {
89 	u_short	bdev_type;	/* data link layer type, codes below */
90 	u_short	bdev_hdrlen;	/* length of a hardware packet header */
91 };
92 
93 /*
94  * Structure prepended to each packet.
95  */
96 struct bpf_hdr {
97 	struct timeval	bh_tstamp;	/* time stamp */
98 	u_long		bh_caplen;	/* length of captured portion */
99 	u_long		bh_datalen;	/* original length of packet */
100 	u_short		bh_hdrlen;	/* length of bpf header (this struct
101 					   plus alignment padding) */
102 };
103 /*
104  * Because the structure above is not a multiple of 4 bytes, some compilers
105  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
106  * Only the kernel needs to know about it; applications use bh_hdrlen.
107  */
108 #ifdef KERNEL
109 #define SIZEOF_BPF_HDR 18
110 #endif
111 
112 /*
113  * Data-link level type codes.
114  * Currently, only ENDT_10MB and DLT_SLIP are supported.
115  */
116 #define DLT_EN10MB	1	/* Ethernet (10Mb) */
117 #define DLT_EN3MB	2	/* Experimental Ethernet (3Mb) */
118 #define DLT_AX25	3	/* Amateur Radio AX.25 */
119 #define DLT_PRONET	4	/* Proteon ProNET Token Ring */
120 #define DLT_CHAOS	5	/* Chaos */
121 #define DLT_IEEE802	6	/* IEEE 802 Networks */
122 #define DLT_ARCNET	7	/* ARCNET */
123 #define DLT_SLIP	8	/* Serial Line IP */
124 #define DLT_PPP		9	/* Point-to-point Protocol */
125 #define DLT_FDDI	10	/* FDDI */
126 
127 /*
128  * The opcodes are defined as an enumeration.  However, they are stored
129  * explicitly in the code array as 'u_short'.
130  */
131 enum bpf_code {
132 #define OPDEF(opcode, opstr) opcode ,
133 #include <net/bpfcodes.h>
134 #undef OPDEF
135 	/* this idea is borrowed from gcc */
136 	LAST_AND_UNUSED_ENUM
137 };
138 
139 #define BPF_NCODES ((unsigned)LAST_AND_UNUSED_ENUM)
140 #define BPF_VALIDCODE(code) ((unsigned)(code) < BPF_NCODES)
141 
142 /*
143  * The instruction data structure.
144  */
145 struct bpf_insn {
146 	u_short	code;
147 	u_char 	jt;
148 	u_char 	jf;
149 	long	k;
150 };
151 
152 /*
153  * Macros for array initializers.
154  */
155 #define BPF_STMT(code, k) { (u_short)code, 0, 0, k }
156 #define BPF_JUMP(code, k, jt, jf) { (u_short)code, jt, jf, k }
157 
158 #ifdef KERNEL
159 extern u_int bpf_filter();
160 extern void bpfattach();
161 extern void bpf_tap();
162 extern void bpf_mtap();
163 #endif
164 
165 /*
166  * These two macros are sensitive to the order in which the
167  * opcodes appear in bpfcodes.h.
168  */
169 #define BPF_ISJUMP(code) ((unsigned)(code) <= (unsigned)EQOp)
170 #define BPF_ISLEAF(code) ((unsigned)(code) >= (unsigned)RetOp)
171 
172 /*
173  * Number of scratch memory words.
174  */
175 #define BPF_MEMWORDS 16
176