blob: bc3ec6ddfa31f556d0fb1f097d7b8c5aee4011f6 [file] [log] [blame] [raw]
/*
* Copyright (C) 2001-2004 by Darren Reed.
*
* See the IPFILTER.LICENCE file for details on licencing.
*/
%{
#include "ipf.h"
#include <syslog.h>
#undef OPT_NAT
#undef OPT_VERBOSE
#include "ipmon_l.h"
#include "ipmon.h"
#define YYDEBUG 1
extern void yyerror __P((char *));
extern int yyparse __P((void));
extern int yylex __P((void));
extern int yydebug;
extern FILE *yyin;
extern int yylineNum;
typedef struct opt {
struct opt *o_next;
int o_line;
int o_type;
int o_num;
char *o_str;
struct in_addr o_ip;
} opt_t;
static void build_action __P((struct opt *));
static opt_t *new_opt __P((int));
static void free_action __P((ipmon_action_t *));
static ipmon_action_t *alist = NULL;
%}
%union {
char *str;
u_32_t num;
struct in_addr addr;
struct opt *opt;
union i6addr ip6;
}
%token <num> YY_NUMBER YY_HEX
%token <str> YY_STR
%token <ip6> YY_IPV6
%token YY_COMMENT
%token YY_CMP_EQ YY_CMP_NE YY_CMP_LE YY_CMP_GE YY_CMP_LT YY_CMP_GT
%token YY_RANGE_OUT YY_RANGE_IN
%token IPM_MATCH IPM_BODY IPM_COMMENT IPM_DIRECTION IPM_DSTIP IPM_DSTPORT
%token IPM_EVERY IPM_EXECUTE IPM_GROUP IPM_INTERFACE IPM_IN IPM_NO IPM_OUT
%token IPM_PACKET IPM_PACKETS IPM_POOL IPM_PROTOCOL IPM_RESULT IPM_RULE
%token IPM_SECOND IPM_SECONDS IPM_SRCIP IPM_SRCPORT IPM_LOGTAG IPM_WITH
%token IPM_DO IPM_SAVE IPM_SYSLOG IPM_NOTHING IPM_RAW IPM_TYPE IPM_NAT
%token IPM_STATE IPM_NATTAG IPM_IPF
%type <addr> ipv4
%type <opt> direction dstip dstport every execute group interface
%type <opt> protocol result rule srcip srcport logtag matching
%type <opt> matchopt nattag type doopt doing save syslog nothing
%type <num> saveopts saveopt typeopt
%%
file: line
| assign
| file line
| file assign
;
line: IPM_MATCH '{' matching '}' IPM_DO '{' doing '}' ';'
{ build_action($3); resetlexer(); }
| IPM_COMMENT
| YY_COMMENT
;
assign: YY_STR assigning YY_STR ';' { set_variable($1, $3);
resetlexer();
free($1);
free($3);
yyvarnext = 0;
}
;
assigning:
'=' { yyvarnext = 1; }
;
matching:
matchopt { $$ = $1; }
| matchopt ',' matching { $1->o_next = $3; $$ = $1; }
;
matchopt:
direction { $$ = $1; }
| dstip { $$ = $1; }
| dstport { $$ = $1; }
| every { $$ = $1; }
| group { $$ = $1; }
| interface { $$ = $1; }
| protocol { $$ = $1; }
| result { $$ = $1; }
| rule { $$ = $1; }
| srcip { $$ = $1; }
| srcport { $$ = $1; }
| logtag { $$ = $1; }
| nattag { $$ = $1; }
| type { $$ = $1; }
;
doing:
doopt { $$ = $1; }
| doopt ',' doing { $1->o_next = $3; $$ = $1; }
;
doopt:
execute { $$ = $1; }
| save { $$ = $1; }
| syslog { $$ = $1; }
| nothing { $$ = $1; }
;
direction:
IPM_DIRECTION '=' IPM_IN { $$ = new_opt(IPM_DIRECTION);
$$->o_num = IPM_IN; }
| IPM_DIRECTION '=' IPM_OUT { $$ = new_opt(IPM_DIRECTION);
$$->o_num = IPM_OUT; }
;
dstip: IPM_DSTIP '=' ipv4 '/' YY_NUMBER { $$ = new_opt(IPM_DSTIP);
$$->o_ip = $3;
$$->o_num = $5; }
;
dstport:
IPM_DSTPORT '=' YY_NUMBER { $$ = new_opt(IPM_DSTPORT);
$$->o_num = $3; }
| IPM_DSTPORT '=' YY_STR { $$ = new_opt(IPM_DSTPORT);
$$->o_str = $3; }
;
every: IPM_EVERY IPM_SECOND { $$ = new_opt(IPM_SECOND);
$$->o_num = 1; }
| IPM_EVERY YY_NUMBER IPM_SECONDS { $$ = new_opt(IPM_SECOND);
$$->o_num = $2; }
| IPM_EVERY IPM_PACKET { $$ = new_opt(IPM_PACKET);
$$->o_num = 1; }
| IPM_EVERY YY_NUMBER IPM_PACKETS { $$ = new_opt(IPM_PACKET);
$$->o_num = $2; }
;
group: IPM_GROUP '=' YY_NUMBER { $$ = new_opt(IPM_GROUP);
$$->o_num = $3; }
| IPM_GROUP '=' YY_STR { $$ = new_opt(IPM_GROUP);
$$->o_str = $3; }
;
interface:
IPM_INTERFACE '=' YY_STR { $$ = new_opt(IPM_INTERFACE);
$$->o_str = $3; }
;
logtag: IPM_LOGTAG '=' YY_NUMBER { $$ = new_opt(IPM_LOGTAG);
$$->o_num = $3; }
;
nattag: IPM_NATTAG '=' YY_STR { $$ = new_opt(IPM_NATTAG);
$$->o_str = $3; }
;
protocol:
IPM_PROTOCOL '=' YY_NUMBER { $$ = new_opt(IPM_PROTOCOL);
$$->o_num = $3; }
| IPM_PROTOCOL '=' YY_STR { $$ = new_opt(IPM_PROTOCOL);
$$->o_num = getproto($3);
free($3);
}
;
result: IPM_RESULT '=' YY_STR { $$ = new_opt(IPM_RESULT);
$$->o_str = $3; }
;
rule: IPM_RULE '=' YY_NUMBER { $$ = new_opt(IPM_RULE);
$$->o_num = YY_NUMBER; }
;
srcip: IPM_SRCIP '=' ipv4 '/' YY_NUMBER { $$ = new_opt(IPM_SRCIP);
$$->o_ip = $3;
$$->o_num = $5; }
;
srcport:
IPM_SRCPORT '=' YY_NUMBER { $$ = new_opt(IPM_SRCPORT);
$$->o_num = $3; }
| IPM_SRCPORT '=' YY_STR { $$ = new_opt(IPM_SRCPORT);
$$->o_str = $3; }
;
type: IPM_TYPE '=' typeopt { $$ = new_opt(IPM_TYPE);
$$->o_num = $3; }
;
typeopt:
IPM_IPF { $$ = IPL_MAGIC; }
| IPM_NAT { $$ = IPL_MAGIC_NAT; }
| IPM_STATE { $$ = IPL_MAGIC_STATE; }
;
execute:
IPM_EXECUTE YY_STR { $$ = new_opt(IPM_EXECUTE);
$$->o_str = $2; }
;
save: IPM_SAVE saveopts YY_STR { $$ = new_opt(IPM_SAVE);
$$->o_num = $2;
$$->o_str = $3; }
;
saveopts: { $$ = 0; }
| saveopt { $$ = $1; }
| saveopt ',' saveopts { $$ = $1 | $3; }
;
saveopt:
IPM_RAW { $$ = IPMDO_SAVERAW; }
;
syslog: IPM_SYSLOG { $$ = new_opt(IPM_SYSLOG); }
;
nothing:
IPM_NOTHING { $$ = 0; }
;
ipv4: YY_NUMBER '.' YY_NUMBER '.' YY_NUMBER '.' YY_NUMBER
{ if ($1 > 255 || $3 > 255 || $5 > 255 || $7 > 255) {
yyerror("Invalid octet string for IP address");
return 0;
}
$$.s_addr = ($1 << 24) | ($3 << 16) | ($5 << 8) | $7;
$$.s_addr = htonl($$.s_addr);
}
%%
static struct wordtab yywords[] = {
{ "body", IPM_BODY },
{ "direction", IPM_DIRECTION },
{ "do", IPM_DO },
{ "dstip", IPM_DSTIP },
{ "dstport", IPM_DSTPORT },
{ "every", IPM_EVERY },
{ "execute", IPM_EXECUTE },
{ "group", IPM_GROUP },
{ "in", IPM_IN },
{ "interface", IPM_INTERFACE },
{ "ipf", IPM_IPF },
{ "logtag", IPM_LOGTAG },
{ "match", IPM_MATCH },
{ "nat", IPM_NAT },
{ "nattag", IPM_NATTAG },
{ "no", IPM_NO },
{ "nothing", IPM_NOTHING },
{ "out", IPM_OUT },
{ "packet", IPM_PACKET },
{ "packets", IPM_PACKETS },
{ "protocol", IPM_PROTOCOL },
{ "result", IPM_RESULT },
{ "rule", IPM_RULE },
{ "save", IPM_SAVE },
{ "second", IPM_SECOND },
{ "seconds", IPM_SECONDS },
{ "srcip", IPM_SRCIP },
{ "srcport", IPM_SRCPORT },
{ "state", IPM_STATE },
{ "syslog", IPM_SYSLOG },
{ "with", IPM_WITH },
{ NULL, 0 }
};
static int macflags[17][2] = {
{ IPM_DIRECTION, IPMAC_DIRECTION },
{ IPM_DSTIP, IPMAC_DSTIP },
{ IPM_DSTPORT, IPMAC_DSTPORT },
{ IPM_GROUP, IPMAC_GROUP },
{ IPM_INTERFACE, IPMAC_INTERFACE },
{ IPM_LOGTAG, IPMAC_LOGTAG },
{ IPM_NATTAG, IPMAC_NATTAG },
{ IPM_PACKET, IPMAC_EVERY },
{ IPM_PROTOCOL, IPMAC_PROTOCOL },
{ IPM_RESULT, IPMAC_RESULT },
{ IPM_RULE, IPMAC_RULE },
{ IPM_SECOND, IPMAC_EVERY },
{ IPM_SRCIP, IPMAC_SRCIP },
{ IPM_SRCPORT, IPMAC_SRCPORT },
{ IPM_TYPE, IPMAC_TYPE },
{ IPM_WITH, IPMAC_WITH },
{ 0, 0 }
};
static opt_t *new_opt(type)
int type;
{
opt_t *o;
o = (opt_t *)malloc(sizeof(*o));
o->o_type = type;
o->o_line = yylineNum;
o->o_num = 0;
o->o_str = (char *)0;
o->o_next = NULL;
return o;
}
static void build_action(olist)
opt_t *olist;
{
ipmon_action_t *a;
opt_t *o;
char c;
int i;
a = (ipmon_action_t *)calloc(1, sizeof(*a));
if (a == NULL)
return;
while ((o = olist) != NULL) {
/*
* Check to see if the same comparator is being used more than
* once per matching statement.
*/
for (i = 0; macflags[i][0]; i++)
if (macflags[i][0] == o->o_type)
break;
if (macflags[i][1] & a->ac_mflag) {
fprintf(stderr, "%s redfined on line %d\n",
yykeytostr(o->o_type), yylineNum);
if (o->o_str != NULL)
free(o->o_str);
olist = o->o_next;
free(o);
continue;
}
a->ac_mflag |= macflags[i][1];
switch (o->o_type)
{
case IPM_DIRECTION :
a->ac_direction = o->o_num;
break;
case IPM_DSTIP :
a->ac_dip = o->o_ip.s_addr;
a->ac_dmsk = htonl(0xffffffff << (32 - o->o_num));
break;
case IPM_DSTPORT :
a->ac_dport = htons(o->o_num);
break;
case IPM_EXECUTE :
a->ac_exec = o->o_str;
c = *o->o_str;
if (c== '"'|| c == '\'') {
if (o->o_str[strlen(o->o_str) - 1] == c) {
a->ac_run = strdup(o->o_str + 1);
a->ac_run[strlen(a->ac_run) - 1] ='\0';
} else
a->ac_run = o->o_str;
} else
a->ac_run = o->o_str;
o->o_str = NULL;
break;
case IPM_INTERFACE :
a->ac_iface = o->o_str;
o->o_str = NULL;
break;
case IPM_GROUP :
if (o->o_str != NULL)
strncpy(a->ac_group, o->o_str, FR_GROUPLEN);
else
sprintf(a->ac_group, "%d", o->o_num);
break;
case IPM_LOGTAG :
a->ac_logtag = o->o_num;
break;
case IPM_NATTAG :
strncpy(a->ac_nattag, o->o_str, sizeof(a->ac_nattag));
break;
case IPM_PACKET :
a->ac_packet = o->o_num;
break;
case IPM_PROTOCOL :
a->ac_proto = o->o_num;
break;
case IPM_RULE :
a->ac_rule = o->o_num;
break;
case IPM_RESULT :
if (!strcasecmp(o->o_str, "pass"))
a->ac_result = IPMR_PASS;
else if (!strcasecmp(o->o_str, "block"))
a->ac_result = IPMR_BLOCK;
else if (!strcasecmp(o->o_str, "nomatch"))
a->ac_result = IPMR_NOMATCH;
else if (!strcasecmp(o->o_str, "log"))
a->ac_result = IPMR_LOG;
break;
case IPM_SECOND :
a->ac_second = o->o_num;
break;
case IPM_SRCIP :
a->ac_sip = o->o_ip.s_addr;
a->ac_smsk = htonl(0xffffffff << (32 - o->o_num));
break;
case IPM_SRCPORT :
a->ac_sport = htons(o->o_num);
break;
case IPM_SAVE :
if (a->ac_savefile != NULL) {
fprintf(stderr, "%s redfined on line %d\n",
yykeytostr(o->o_type), yylineNum);
break;
}
a->ac_savefile = strdup(o->o_str);
a->ac_savefp = fopen(o->o_str, "a");
a->ac_dflag |= o->o_num & IPMDO_SAVERAW;
break;
case IPM_SYSLOG :
if (a->ac_syslog != 0) {
fprintf(stderr, "%s redfined on line %d\n",
yykeytostr(o->o_type), yylineNum);
break;
}
a->ac_syslog = 1;
break;
case IPM_TYPE :
a->ac_type = o->o_num;
break;
case IPM_WITH :
break;
default :
break;
}
olist = o->o_next;
if (o->o_str != NULL)
free(o->o_str);
free(o);
}
a->ac_next = alist;
alist = a;
}
int check_action(buf, log, opts, lvl)
char *buf, *log;
int opts, lvl;
{
ipmon_action_t *a;
struct timeval tv;
ipflog_t *ipf;
tcphdr_t *tcp;
iplog_t *ipl;
int matched;
u_long t1;
ip_t *ip;
matched = 0;
ipl = (iplog_t *)buf;
ipf = (ipflog_t *)(ipl +1);
ip = (ip_t *)(ipf + 1);
tcp = (tcphdr_t *)((char *)ip + (IP_HL(ip) << 2));
for (a = alist; a != NULL; a = a->ac_next) {
if ((a->ac_mflag & IPMAC_DIRECTION) != 0) {
if (a->ac_direction == IPM_IN) {
if ((ipf->fl_flags & FR_INQUE) == 0)
continue;
} else if (a->ac_direction == IPM_OUT) {
if ((ipf->fl_flags & FR_OUTQUE) == 0)
continue;
}
}
if ((a->ac_type != 0) && (a->ac_type != ipl->ipl_magic))
continue;
if ((a->ac_mflag & IPMAC_EVERY) != 0) {
gettimeofday(&tv, NULL);
t1 = tv.tv_sec - a->ac_lastsec;
if (tv.tv_usec <= a->ac_lastusec)
t1--;
if (a->ac_second != 0) {
if (t1 < a->ac_second)
continue;
a->ac_lastsec = tv.tv_sec;
a->ac_lastusec = tv.tv_usec;
}
if (a->ac_packet != 0) {
if (a->ac_pktcnt == 0)
a->ac_pktcnt++;
else if (a->ac_pktcnt == a->ac_packet) {
a->ac_pktcnt = 0;
continue;
} else {
a->ac_pktcnt++;
continue;
}
}
}
if ((a->ac_mflag & IPMAC_DSTIP) != 0) {
if ((ip->ip_dst.s_addr & a->ac_dmsk) != a->ac_dip)
continue;
}
if ((a->ac_mflag & IPMAC_DSTPORT) != 0) {
if (ip->ip_p != IPPROTO_UDP && ip->ip_p != IPPROTO_TCP)
continue;
if (tcp->th_dport != a->ac_dport)
continue;
}
if ((a->ac_mflag & IPMAC_GROUP) != 0) {
if (strncmp(a->ac_group, ipf->fl_group,
FR_GROUPLEN) != 0)
continue;
}
if ((a->ac_mflag & IPMAC_INTERFACE) != 0) {
if (strcmp(a->ac_iface, ipf->fl_ifname))
continue;
}
if ((a->ac_mflag & IPMAC_PROTOCOL) != 0) {
if (a->ac_proto != ip->ip_p)
continue;
}
if ((a->ac_mflag & IPMAC_RESULT) != 0) {
if ((ipf->fl_flags & FF_LOGNOMATCH) != 0) {
if (a->ac_result != IPMR_NOMATCH)
continue;
} else if (FR_ISPASS(ipf->fl_flags)) {
if (a->ac_result != IPMR_PASS)
continue;
} else if (FR_ISBLOCK(ipf->fl_flags)) {
if (a->ac_result != IPMR_BLOCK)
continue;
} else { /* Log only */
if (a->ac_result != IPMR_LOG)
continue;
}
}
if ((a->ac_mflag & IPMAC_RULE) != 0) {
if (a->ac_rule != ipf->fl_rule)
continue;
}
if ((a->ac_mflag & IPMAC_SRCIP) != 0) {
if ((ip->ip_src.s_addr & a->ac_smsk) != a->ac_sip)
continue;
}
if ((a->ac_mflag & IPMAC_SRCPORT) != 0) {
if (ip->ip_p != IPPROTO_UDP && ip->ip_p != IPPROTO_TCP)
continue;
if (tcp->th_sport != a->ac_sport)
continue;
}
if ((a->ac_mflag & IPMAC_LOGTAG) != 0) {
if (a->ac_logtag != ipf->fl_logtag)
continue;
}
if ((a->ac_mflag & IPMAC_NATTAG) != 0) {
if (strncmp(a->ac_nattag, ipf->fl_nattag.ipt_tag,
IPFTAG_LEN) != 0)
continue;
}
matched = 1;
/*
* It matched so now execute the command
*/
if (a->ac_syslog != 0) {
syslog(lvl, "%s", log);
}
if (a->ac_savefp != NULL) {
if (a->ac_dflag & IPMDO_SAVERAW)
fwrite(ipl, 1, ipl->ipl_dsize, a->ac_savefp);
else
fputs(log, a->ac_savefp);
}
if (a->ac_exec != NULL) {
switch (fork())
{
case 0 :
{
FILE *pi;
pi = popen(a->ac_run, "w");
if (pi != NULL) {
fprintf(pi, "%s\n", log);
if ((opts & OPT_HEXHDR) != 0) {
dumphex(pi, 0, buf,
sizeof(*ipl) +
sizeof(*ipf));
}
if ((opts & OPT_HEXBODY) != 0) {
dumphex(pi, 0, (char *)ip,
ipf->fl_hlen +
ipf->fl_plen);
}
pclose(pi);
}
exit(1);
}
case -1 :
break;
default :
break;
}
}
}
return matched;
}
static void free_action(a)
ipmon_action_t *a;
{
if (a->ac_savefile != NULL) {
free(a->ac_savefile);
a->ac_savefile = NULL;
}
if (a->ac_savefp != NULL) {
fclose(a->ac_savefp);
a->ac_savefp = NULL;
}
if (a->ac_exec != NULL) {
free(a->ac_exec);
if (a->ac_run == a->ac_exec)
a->ac_run = NULL;
a->ac_exec = NULL;
}
if (a->ac_run != NULL) {
free(a->ac_run);
a->ac_run = NULL;
}
if (a->ac_iface != NULL) {
free(a->ac_iface);
a->ac_iface = NULL;
}
a->ac_next = NULL;
free(a);
}
int load_config(file)
char *file;
{
ipmon_action_t *a;
FILE *fp;
char *s;
s = getenv("YYDEBUG");
if (s != NULL)
yydebug = atoi(s);
else
yydebug = 0;
while ((a = alist) != NULL) {
alist = a->ac_next;
free_action(a);
}
yylineNum = 1;
(void) yysettab(yywords);
fp = fopen(file, "r");
if (!fp) {
perror("load_config:fopen:");
return -1;
}
yyin = fp;
while (!feof(fp))
yyparse();
fclose(fp);
return 0;
}