src/lib/libpcap/grammar.y

438 lines
12 KiB
Plaintext

%{
/* $OpenBSD: grammar.y,v 1.24 2024/04/08 02:51:14 jsg Exp $ */
/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
*/
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <net/pfvar.h>
#include <net80211/ieee80211.h>
#include <stdio.h>
#include <string.h>
#include "pcap-int.h"
#include "gencode.h"
#include <pcap-namedb.h>
#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif
#define QSET(q, p, d, a) (q).proto = (p),\
(q).dir = (d),\
(q).addr = (a)
int n_errors = 0;
static struct qual qerr = { Q_UNDEF, Q_UNDEF, Q_UNDEF, Q_UNDEF };
static void
yyerror(char *msg)
{
++n_errors;
bpf_error("%s", msg);
/* NOTREACHED */
}
#ifndef YYBISON
int yyparse(void);
int
pcap_parse(void)
{
return (yyparse());
}
#endif
%}
%union {
int i;
bpf_u_int32 h;
u_char *e;
char *s;
struct stmt *stmt;
struct arth *a;
struct {
struct qual q;
struct block *b;
} blk;
struct block *rblk;
}
%type <blk> expr id nid pid term rterm qid
%type <blk> head
%type <i> pqual dqual aqual ndaqual
%type <a> arth narth
%type <i> byteop pname pnum relop irelop
%type <blk> and or paren not null prog
%type <rblk> other pfvar p80211
%token DST SRC HOST GATEWAY
%token NET MASK PORT LESS GREATER PROTO PROTOCHAIN BYTE
%token ARP RARP IP TCP UDP ICMP IGMP IGRP PIM
%token ATALK DECNET LAT SCA MOPRC MOPDL STP
%token TK_BROADCAST TK_MULTICAST
%token NUM INBOUND OUTBOUND
%token PF_IFNAME PF_RSET PF_RNR PF_SRNR PF_REASON PF_ACTION
%token TYPE SUBTYPE DIR ADDR1 ADDR2 ADDR3 ADDR4
%token LINK
%token GEQ LEQ NEQ
%token ID EID HID HID6
%token LSH RSH
%token LEN RND SAMPLE
%token IPV6 ICMPV6 AH ESP
%token VLAN MPLS
%type <s> ID
%type <e> EID
%type <s> HID HID6
%type <i> NUM action reason type subtype dir
%left OR AND
%nonassoc '!'
%left '|'
%left '&'
%left LSH RSH
%left '+' '-'
%left '*' '/'
%nonassoc UMINUS
%%
prog: null expr
{
finish_parse($2.b);
}
| null
;
null: /* null */ { $$.q = qerr; }
;
expr: term
| expr and term { gen_and($1.b, $3.b); $$ = $3; }
| expr and id { gen_and($1.b, $3.b); $$ = $3; }
| expr or term { gen_or($1.b, $3.b); $$ = $3; }
| expr or id { gen_or($1.b, $3.b); $$ = $3; }
;
and: AND { $$ = $<blk>0; }
;
or: OR { $$ = $<blk>0; }
;
id: nid
| pnum { $$.b = gen_ncode(NULL, (bpf_u_int32)$1,
$$.q = $<blk>0.q); }
| paren pid ')' { $$ = $2; }
;
nid: ID { $$.b = gen_scode($1, $$.q = $<blk>0.q); }
| HID '/' NUM { $$.b = gen_mcode($1, NULL, $3,
$$.q = $<blk>0.q); }
| HID MASK HID { $$.b = gen_mcode($1, $3, 0,
$$.q = $<blk>0.q); }
| HID {
/* Decide how to parse HID based on proto */
$$.q = $<blk>0.q;
switch ($$.q.proto) {
case Q_DECNET:
$$.b = gen_ncode($1, 0, $$.q);
break;
default:
$$.b = gen_ncode($1, 0, $$.q);
break;
}
}
| HID6 '/' NUM {
#ifdef INET6
$$.b = gen_mcode6($1, NULL, $3,
$$.q = $<blk>0.q);
#else
bpf_error("'ip6addr/prefixlen' not supported "
"in this configuration");
#endif /*INET6*/
}
| HID6 {
#ifdef INET6
$$.b = gen_mcode6($1, 0, 128,
$$.q = $<blk>0.q);
#else
bpf_error("'ip6addr' not supported "
"in this configuration");
#endif /*INET6*/
}
| EID { $$.b = gen_ecode($1, $$.q = $<blk>0.q); }
| not id { gen_not($2.b); $$ = $2; }
;
not: '!' { $$ = $<blk>0; }
;
paren: '(' { $$ = $<blk>0; }
;
pid: nid
| qid and id { gen_and($1.b, $3.b); $$ = $3; }
| qid or id { gen_or($1.b, $3.b); $$ = $3; }
;
qid: pnum { $$.b = gen_ncode(NULL, (bpf_u_int32)$1,
$$.q = $<blk>0.q); }
| pid
;
term: rterm
| not term { gen_not($2.b); $$ = $2; }
;
head: pqual dqual aqual { QSET($$.q, $1, $2, $3); }
| pqual dqual { QSET($$.q, $1, $2, Q_DEFAULT); }
| pqual aqual { QSET($$.q, $1, Q_DEFAULT, $2); }
| pqual PROTO { QSET($$.q, $1, Q_DEFAULT, Q_PROTO); }
| pqual PROTOCHAIN { QSET($$.q, $1, Q_DEFAULT, Q_PROTOCHAIN); }
| pqual ndaqual { QSET($$.q, $1, Q_DEFAULT, $2); }
;
rterm: head id { $$ = $2; }
| paren expr ')' { $$.b = $2.b; $$.q = $1.q; }
| pname { $$.b = gen_proto_abbrev($1); $$.q = qerr; }
| arth relop arth { $$.b = gen_relation($2, $1, $3, 0);
$$.q = qerr; }
| arth irelop arth { $$.b = gen_relation($2, $1, $3, 1);
$$.q = qerr; }
| other { $$.b = $1; $$.q = qerr; }
;
/* protocol level qualifiers */
pqual: pname
| { $$ = Q_DEFAULT; }
;
/* 'direction' qualifiers */
dqual: SRC { $$ = Q_SRC; }
| DST { $$ = Q_DST; }
| SRC OR DST { $$ = Q_OR; }
| DST OR SRC { $$ = Q_OR; }
| SRC AND DST { $$ = Q_AND; }
| DST AND SRC { $$ = Q_AND; }
| ADDR1 { $$ = Q_ADDR1; }
| ADDR2 { $$ = Q_ADDR2; }
| ADDR3 { $$ = Q_ADDR3; }
| ADDR4 { $$ = Q_ADDR4; }
;
/* address type qualifiers */
aqual: HOST { $$ = Q_HOST; }
| NET { $$ = Q_NET; }
| PORT { $$ = Q_PORT; }
;
/* non-directional address type qualifiers */
ndaqual: GATEWAY { $$ = Q_GATEWAY; }
;
pname: LINK { $$ = Q_LINK; }
| IP { $$ = Q_IP; }
| ARP { $$ = Q_ARP; }
| RARP { $$ = Q_RARP; }
| TCP { $$ = Q_TCP; }
| UDP { $$ = Q_UDP; }
| ICMP { $$ = Q_ICMP; }
| IGMP { $$ = Q_IGMP; }
| IGRP { $$ = Q_IGRP; }
| PIM { $$ = Q_PIM; }
| ATALK { $$ = Q_ATALK; }
| DECNET { $$ = Q_DECNET; }
| LAT { $$ = Q_LAT; }
| SCA { $$ = Q_SCA; }
| MOPDL { $$ = Q_MOPDL; }
| MOPRC { $$ = Q_MOPRC; }
| IPV6 { $$ = Q_IPV6; }
| ICMPV6 { $$ = Q_ICMPV6; }
| AH { $$ = Q_AH; }
| ESP { $$ = Q_ESP; }
| STP { $$ = Q_STP; }
;
other: pqual TK_BROADCAST { $$ = gen_broadcast($1); }
| pqual TK_MULTICAST { $$ = gen_multicast($1); }
| LESS NUM { $$ = gen_less($2); }
| GREATER NUM { $$ = gen_greater($2); }
| BYTE NUM byteop NUM { $$ = gen_byteop($3, $2, $4); }
| INBOUND { $$ = gen_inbound(0); }
| OUTBOUND { $$ = gen_inbound(1); }
| VLAN pnum { $$ = gen_vlan($2); }
| VLAN { $$ = gen_vlan(-1); }
| MPLS pnum { $$ = gen_mpls($2); }
| MPLS { $$ = gen_mpls(-1); }
| pfvar { $$ = $1; }
| pqual p80211 { $$ = $2; }
| SAMPLE NUM { $$ = gen_sample($2); }
;
pfvar: PF_IFNAME ID { $$ = gen_pf_ifname($2); }
| PF_RSET ID { $$ = gen_pf_ruleset($2); }
| PF_RNR NUM { $$ = gen_pf_rnr($2); }
| PF_SRNR NUM { $$ = gen_pf_srnr($2); }
| PF_REASON reason { $$ = gen_pf_reason($2); }
| PF_ACTION action { $$ = gen_pf_action($2); }
;
reason: NUM { $$ = $1; }
| ID { const char *reasons[] = PFRES_NAMES;
int i;
for (i = 0; reasons[i]; i++) {
if (strcasecmp($1, reasons[i]) == 0) {
$$ = i;
break;
}
}
if (reasons[i] == NULL)
bpf_error("unknown PF reason");
}
;
action: ID { if (strcasecmp($1, "pass") == 0 ||
strcasecmp($1, "accept") == 0)
$$ = PF_PASS;
else if (strcasecmp($1, "drop") == 0 ||
strcasecmp($1, "block") == 0)
$$ = PF_DROP;
else if (strcasecmp($1, "match") == 0)
$$ = PF_MATCH;
else if (strcasecmp($1, "rdr") == 0)
$$ = PF_RDR;
else if (strcasecmp($1, "nat") == 0)
$$ = PF_NAT;
else if (strcasecmp($1, "binat") == 0)
$$ = PF_BINAT;
else if (strcasecmp($1, "scrub") == 0)
$$ = PF_SCRUB;
else
bpf_error("unknown PF action");
}
;
p80211: TYPE type SUBTYPE subtype
{ $$ = gen_p80211_type($2 | $4,
IEEE80211_FC0_TYPE_MASK |
IEEE80211_FC0_SUBTYPE_MASK);
}
| TYPE type { $$ = gen_p80211_type($2,
IEEE80211_FC0_TYPE_MASK); }
| SUBTYPE subtype { $$ = gen_p80211_type($2,
IEEE80211_FC0_SUBTYPE_MASK); }
| DIR dir { $$ = gen_p80211_fcdir($2); }
;
type: NUM
| ID { if (strcasecmp($1, "data") == 0)
$$ = IEEE80211_FC0_TYPE_DATA;
else if (strcasecmp($1, "mgt") == 0 ||
strcasecmp($1, "management") == 0)
$$ = IEEE80211_FC0_TYPE_MGT;
else if (strcasecmp($1, "ctl") == 0 ||
strcasecmp($1, "control") == 0)
$$ = IEEE80211_FC0_TYPE_CTL;
else
bpf_error("unknown 802.11 type");
}
;
subtype: NUM
| ID { if (strcasecmp($1, "assocreq") == 0)
$$ = IEEE80211_FC0_SUBTYPE_ASSOC_REQ;
else if (strcasecmp($1, "assocresp") == 0)
$$ = IEEE80211_FC0_SUBTYPE_ASSOC_RESP;
else if (strcasecmp($1, "reassocreq") == 0)
$$ = IEEE80211_FC0_SUBTYPE_REASSOC_REQ;
else if (strcasecmp($1, "reassocresp") == 0)
$$ = IEEE80211_FC0_SUBTYPE_REASSOC_RESP;
else if (strcasecmp($1, "probereq") == 0)
$$ = IEEE80211_FC0_SUBTYPE_PROBE_REQ;
else if (strcasecmp($1, "proberesp") == 0)
$$ = IEEE80211_FC0_SUBTYPE_PROBE_RESP;
else if (strcasecmp($1, "beacon") == 0)
$$ = IEEE80211_FC0_SUBTYPE_BEACON;
else if (strcasecmp($1, "atim") == 0)
$$ = IEEE80211_FC0_SUBTYPE_ATIM;
else if (strcasecmp($1, "disassoc") == 0 ||
strcasecmp($1, "disassociation") == 0)
$$ = IEEE80211_FC0_SUBTYPE_DISASSOC;
else if (strcasecmp($1, "auth") == 0 ||
strcasecmp($1, "authentication") == 0)
$$ = IEEE80211_FC0_SUBTYPE_AUTH;
else if (strcasecmp($1, "deauth") == 0 ||
strcasecmp($1, "deauthentication") == 0)
$$ = IEEE80211_FC0_SUBTYPE_DEAUTH;
else if (strcasecmp($1, "data") == 0)
$$ = IEEE80211_FC0_SUBTYPE_DATA;
else
bpf_error("unknown 802.11 subtype");
}
;
dir: NUM
| ID { if (strcasecmp($1, "nods") == 0)
$$ = IEEE80211_FC1_DIR_NODS;
else if (strcasecmp($1, "tods") == 0)
$$ = IEEE80211_FC1_DIR_TODS;
else if (strcasecmp($1, "fromds") == 0)
$$ = IEEE80211_FC1_DIR_FROMDS;
else if (strcasecmp($1, "dstods") == 0)
$$ = IEEE80211_FC1_DIR_DSTODS;
else
bpf_error("unknown 802.11 direction");
}
;
relop: '>' { $$ = BPF_JGT; }
| GEQ { $$ = BPF_JGE; }
| '=' { $$ = BPF_JEQ; }
;
irelop: LEQ { $$ = BPF_JGT; }
| '<' { $$ = BPF_JGE; }
| NEQ { $$ = BPF_JEQ; }
;
arth: pnum { $$ = gen_loadi($1); }
| narth
;
narth: pname '[' arth ']' { $$ = gen_load($1, $3, 1); }
| pname '[' arth ':' NUM ']' { $$ = gen_load($1, $3, $5); }
| arth '+' arth { $$ = gen_arth(BPF_ADD, $1, $3); }
| arth '-' arth { $$ = gen_arth(BPF_SUB, $1, $3); }
| arth '*' arth { $$ = gen_arth(BPF_MUL, $1, $3); }
| arth '/' arth { $$ = gen_arth(BPF_DIV, $1, $3); }
| arth '&' arth { $$ = gen_arth(BPF_AND, $1, $3); }
| arth '|' arth { $$ = gen_arth(BPF_OR, $1, $3); }
| arth LSH arth { $$ = gen_arth(BPF_LSH, $1, $3); }
| arth RSH arth { $$ = gen_arth(BPF_RSH, $1, $3); }
| '-' arth %prec UMINUS { $$ = gen_neg($2); }
| paren narth ')' { $$ = $2; }
| LEN { $$ = gen_loadlen(); }
| RND { $$ = gen_loadrnd(); }
;
byteop: '&' { $$ = '&'; }
| '|' { $$ = '|'; }
| '<' { $$ = '<'; }
| '>' { $$ = '>'; }
| '=' { $$ = '='; }
;
pnum: NUM
| paren pnum ')' { $$ = $2; }
;
%%