1 /* 2 * Copyright (c) 1990, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from the Stanford/CMU enet packet filter, 6 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 7 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 8 * Berkeley Laboratory. 9 * 10 * %sccs.include.redist.c% 11 * 12 * @(#)bpfdesc.h 8.1 (Berkeley) 06/10/93 13 * 14 * @(#) $Header: bpfdesc.h,v 1.9 91/10/27 21:22:38 mccanne Exp $ (LBL) 15 */ 16 17 /* 18 * Descriptor associated with each open bpf file. 19 */ 20 struct bpf_d { 21 struct bpf_d *bd_next; /* Linked list of descriptors */ 22 /* 23 * Buffer slots: two mbuf clusters buffer the incoming packets. 24 * The model has three slots. Sbuf is always occupied. 25 * sbuf (store) - Receive interrupt puts packets here. 26 * hbuf (hold) - When sbuf is full, put cluster here and 27 * wakeup read (replace sbuf with fbuf). 28 * fbuf (free) - When read is done, put cluster here. 29 * On receiving, if sbuf is full and fbuf is 0, packet is dropped. 30 */ 31 caddr_t bd_sbuf; /* store slot */ 32 caddr_t bd_hbuf; /* hold slot */ 33 caddr_t bd_fbuf; /* free slot */ 34 int bd_slen; /* current length of store buffer */ 35 int bd_hlen; /* current length of hold buffer */ 36 37 int bd_bufsize; /* absolute length of buffers */ 38 39 struct bpf_if * bd_bif; /* interface descriptor */ 40 u_long bd_rtout; /* Read timeout in 'ticks' */ 41 struct bpf_insn *bd_filter; /* filter code */ 42 u_long bd_rcount; /* number of packets received */ 43 u_long bd_dcount; /* number of packets dropped */ 44 45 u_char bd_promisc; /* true if listening promiscuously */ 46 u_char bd_state; /* idle, waiting, or timed out */ 47 u_char bd_immediate; /* true to return on packet arrival */ 48 #if BSD < 199103 49 u_char bd_selcoll; /* true if selects collide */ 50 int bd_timedout; 51 struct proc * bd_selproc; /* process that last selected us */ 52 #else 53 u_char bd_pad; /* explicit alignment */ 54 struct selinfo bd_sel; /* bsd select info */ 55 #endif 56 }; 57 58 /* 59 * Descriptor associated with each attached hardware interface. 60 */ 61 struct bpf_if { 62 struct bpf_if *bif_next; /* list of all interfaces */ 63 struct bpf_d *bif_dlist; /* descriptor list */ 64 struct bpf_if **bif_driverp; /* pointer into softc */ 65 u_int bif_dlt; /* link layer type */ 66 u_int bif_hdrlen; /* length of header (with padding) */ 67 struct ifnet *bif_ifp; /* correspoding interface */ 68 }; 69 70 #ifdef KERNEL 71 int bpf_setf __P((struct bpf_d *, struct bpf_program *)); 72 #endif 73