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/*
* firewall.c - Packet filtering for diald.
*
* Copyright (c) 1994, 1995, 1996 Eric Schenk.
* All rights reserved. Please see the file LICENSE which should be
* distributed with this software for terms of use.
*/
#include "diald.h"
#ifdef __GLIBC__
#include <linux/types.h>
#endif
static FW_unit units[FW_NRUNIT];
static int initialized = 0;
int impulse_init_time = 0;
int impulse_time = 0;
int impulse_fuzz = 0;
void del_connection(FW_Connection *);
/*
* Initialize the units.
*/
static void init_units(void)
{
int i;
memset(units,0,sizeof(units));
for (i = 0; i < FW_NRUNIT; i++) {
units[i].used = 0;
units[i].filters = NULL;
units[i].last = NULL;
units[i].connections = malloc(sizeof(FW_Connection));
units[i].nrules = 0;
units[i].nfilters = 0;
if (!units[i].connections) {
syslog(LOG_ERR,"Out of memory! AIIEEE!");
die(1);
}
units[i].connections->next = units[i].connections->prev
= units[i].connections;
}
initialized = 1;
}
/* is the time given by "clock" in the given slot? */
static unsigned int in_slot(FW_Timeslot *slot, time_t *clock)
{
struct tm *ltime = localtime(clock);
int ctime = ltime->tm_hour*60*60+ltime->tm_min*60+ltime->tm_sec;
#ifdef 0
syslog(LOG_INFO,"slot check: %d %d %d %d",
ltime->tm_sec+ltime->tm_min*60+ltime->tm_hour*60*60, ltime->tm_wday,
ltime->tm_mday, ltime->tm_mon);
#endif
while (slot) {
#ifdef 0
syslog(LOG_INFO,"slot def: %d %d %x %x %x",
slot->start, slot->end, slot->wday, slot->mday, slot->month);
#endif 0
if ((slot->start <= ctime)
&& (ctime <= slot->end)
&& (slot->wday & (1<<ltime->tm_wday))
&& (slot->mday & (1<<(ltime->tm_mday-1)))
&& (slot->month & (1<<ltime->tm_mon))) {
return 1;
}
slot = slot->next;
}
return 0;
}
/*
* return 0 if the given time is in the given slots active time set.
* Otherwise return the number of seconds until the slot is next active, or
* the number of seconds until the next occurance of 00:00 hours, whichever
* comes first.
*/
static unsigned int slot_start_timeout(FW_Timeslot *slot, time_t *clock)
{
struct tm *ltime = localtime(clock);
int ctime, mintime;
if (in_slot(slot,clock)) return 0;
/* Ok, we are currently NOT in this slot's time range. */
ctime = ltime->tm_hour*60*60 + ltime->tm_min*60 + ltime->tm_sec;
mintime = 24*60*60 - ctime;
while (slot) {
if ((slot->wday & (1<<ltime->tm_wday))
&& (slot->mday & (1<<(ltime->tm_mday-1)))
&& (slot->month & (1<<ltime->tm_mon))
&& (slot->start >= ctime)) {
/* Ok, this slot disjunct occurs today */
if (mintime >= (slot->start - ctime))
mintime = slot->start - ctime;
}
slot = slot->next;
}
return mintime;
}
/*
* return 0 if the given time is not in the given slots active time set.
* Otherwise return the number of seconds until the slot times out, or
* the number of seconds until the next occurance of 00:00 hours, whichever
* comes first.
*/
static unsigned int slot_end_timeout(FW_Timeslot *slot, time_t *clock)
{
struct tm *ltime = localtime(clock);
int ctime, maxtime;
if (!in_slot(slot,clock)) return 0;
/* Ok, we are currently in this slot's time range. */
ctime = ltime->tm_hour*60*60 + ltime->tm_min*60 + ltime->tm_sec;
maxtime = -1;
while (slot) {
if ((slot->wday & (1<<ltime->tm_wday))
&& (slot->mday & (1<<(ltime->tm_mday-1)))
&& (slot->month & (1<<ltime->tm_mon))
&& (slot->start <= ctime)
&& (ctime <= slot->end)) {
/* Ok, this slot disjunct is active now */
int t = slot->end - ctime;
if (maxtime <= t)
maxtime = t;
}
slot = slot->next;
}
if (maxtime == -1)
return 24*60*60 - ctime;
else
return maxtime;
}
/* Find a connection in the queue */
static FW_Connection *find_connection(FW_unit *unit, FW_ID *id)
{
FW_Connection *c = unit->connections->next;
/* look for a connection that matches this one */
while (c != unit->connections) {
if (memcmp((unsigned char *)&c->id,
(unsigned char *)id,sizeof(FW_ID))==0)
break;
c = c->next;
}
if (c == unit->connections) {
return 0;
} else {
return c;
}
}
/*
* Add/update a connection in the queue.
*/
static void add_connection(
FW_unit *unit, FW_Connection *c, FW_ID *id, unsigned int timeout, TCP_STATE lflags)
{
/* look for a connection that matches this one */
if (c == NULL) {
if (timeout > 0) {
/* no matching connection, add one */
c = malloc(sizeof(FW_Connection));
if (c == 0) {
syslog(LOG_ERR,"Out of memory! AIIEEE!");
die(1);
}
c->id = *id;
init_timer(&c->timer);
c->tcp_state = lflags;
c->unit = unit;
c->timer.data = (void *)c;
c->timer.function = (void *)(void *)del_connection;
c->next = unit->connections->next;
c->prev = unit->connections;
unit->connections->next->prev = c;
unit->connections->next = c;
c->timer.expires = timeout;
add_timer(&c->timer);
if (debug&DEBUG_CONNECTION_QUEUE)
syslog(LOG_INFO,"Adding connection %p @ %ld - timeout %d",c,
time(0),timeout);
}
} else {
/* found a matching connection, toss it's old timer */
if (timeout > 0) {
/* reanimating a ghost? */
del_timer(&c->timer);
c->timer.expires = timeout;
add_timer(&c->timer);
if (debug&DEBUG_CONNECTION_QUEUE)
syslog(LOG_INFO,"Adding connection %p @ %ld - timeout %d",c,
time(0),timeout);
} else {
/* timeout = 0, so toss the connection */
del_timer(&c->timer);
del_connection(c);
}
}
}
/*
* Get a connection out of a queue.
*/
void del_connection(FW_Connection *c)
{
if (debug&DEBUG_CONNECTION_QUEUE)
syslog(LOG_INFO,"Deleting connection %p @ %ld",c,time(0));
c->next->prev = c->prev;
c->prev->next = c->next;
free(c);
}
void del_impulse(FW_unit *unit)
{
if (unit->impulse_mode) {
unit->impulse_mode = 0;
if (impulse_time > 0) {
unit->impulse.data = (void *)unit;
unit->impulse.function = (void *)(void *)del_impulse;
unit->impulse.expires = impulse_time;
if (debug&DEBUG_CONNECTION_QUEUE)
syslog(LOG_INFO,"Refreshing impulse generator: mode %d, time %ld @ %ld",unit->impulse_mode,unit->impulse.expires,time(0));
add_timer(&unit->impulse);
}
} else {
unit->impulse_mode = 1;
impulse_init_time = 0; /* zero the initial impulse time */
if (impulse_fuzz > 0) {
unit->impulse.data = (void *)unit;
unit->impulse.function = (void *)(void *)del_impulse;
unit->impulse.expires = impulse_fuzz;
if (debug&DEBUG_CONNECTION_QUEUE)
syslog(LOG_INFO,"Refreshing impulse generator: mode %d, time %ld @ %ld",unit->impulse_mode,unit->impulse.expires,time(0));
add_timer(&unit->impulse);
}
}
}
/* Check if a forcing rule currently applies to the connection */
static void fw_force_update(FW_unit *unit)
{
FW_Filters *fw;
int timeout, mintime;
time_t clock = time(0);
/* check if the current forcing slot has expired */
if (unit->force_etime > clock) return;
fw = unit->filters;
mintime = 24*60*60;
unit->force = 0;
while (fw) {
if (fw->filt.type == FW_TYPE_UP || fw->filt.type == FW_TYPE_DOWN) {
/* check when the rule is next applicable */
timeout = slot_start_timeout(fw->filt.times,&clock);
if (timeout > 0) {
/* first time at which a previous slot starts */
if (timeout < mintime)
mintime = timeout;
goto next_rule;
} else {
/* time at which the current slot ends */
timeout = slot_end_timeout(fw->filt.times,&clock);
if (timeout < mintime)
mintime = timeout;
}
} else
goto next_rule;
if (fw->filt.type == FW_TYPE_UP)
unit->force = 1;
else
unit->force = 2;
break;
next_rule: /* try the next filter */
fw = fw->next;
}
unit->force_etime = clock + mintime;
}
/* Check if an impulse rule currently applies to the connection */
static void fw_impulse_update(FW_unit *unit, int force)
{
FW_Filters *fw;
int timeout, mintime, itimeout, ifuzz, ftimeout;
time_t clock = time(0);
/* check if the current forcing slot has expired */
if (clock < unit->impulse_etime && !force) return;
fw = unit->filters;
mintime = 24*60*60;
itimeout = 0;
ftimeout = 0;
ifuzz = 0;
while (fw) {
if (fw->filt.type == FW_TYPE_IMPULSE) {
/* check when the rule is next applicable */
timeout = slot_start_timeout(fw->filt.times,&clock);
if (timeout > 0) {
/* Will be applicable soon */
/* first time at which a previous slot starts
* (i.e. schedule changes) */
if (timeout < mintime)
mintime = timeout;
goto next_rule;
} else {
/* time at which the current slot ends */
timeout = slot_end_timeout(fw->filt.times,&clock);
ifuzz = fw->filt.fuzz;
itimeout = fw->filt.timeout;
if (timeout < itimeout) /* chop impulse at change boundary */
itimeout = timeout;
ftimeout = fw->filt.timeout2;
if (timeout < itimeout) /* chop impulse at change boundary */
ftimeout = timeout;
if (timeout < mintime)
mintime = timeout;
}
} else
goto next_rule;
break;
next_rule: /* try the next filter */
fw = fw->next;
}
unit->impulse_etime = clock + mintime;
del_timer(&unit->impulse);
if (unit->up && (itimeout > 0 || (force && ftimeout > 0))) {
/* place the current impulse generator into the impulse queue */
impulse_time = itimeout;
impulse_init_time = ftimeout;
impulse_fuzz = ifuzz;
unit->impulse_mode = 0;
unit->impulse.data = (void *)unit;
unit->impulse.function = (void *)(void *)del_impulse;
unit->impulse.expires = (force)?ftimeout:itimeout;
add_timer(&unit->impulse);
if (debug&DEBUG_CONNECTION_QUEUE)
syslog(LOG_INFO,"Refreshing impulse generator: mode %d, time %ld @ %ld",unit->impulse_mode,unit->impulse.expires,time(0));
} else {
/* set these so that the monitor output is sane */
unit->impulse_mode = 1;
impulse_init_time = 0;
}
}
static void log_packet(int accept, struct iphdr *pkt, int len, int rule)
{
char saddr[20], daddr[20];
struct in_addr addr;
int sport = 0, dport = 0;
struct tcphdr *tcp = (struct tcphdr *)((char *)pkt + 4*pkt->ihl);
struct udphdr *udp = (struct udphdr *)tcp;
addr.s_addr = pkt->saddr;
strcpy(saddr,inet_ntoa(addr));
addr.s_addr = pkt->daddr;
strcpy(daddr,inet_ntoa(addr));
if (pkt->protocol == IPPROTO_TCP || pkt->protocol == IPPROTO_UDP)
sport = ntohs(udp->source), dport = ntohs(udp->dest);
if (pkt->protocol == IPPROTO_TCP) {
syslog(LOG_INFO,
"filter %s rule %d proto %d len %d seq %lx ack %lx flags %s%s%s%s%s%s packet %s,%d => %s,%d",
(accept)?"accepted":"ignored",rule,
pkt->protocol,
ntohs(pkt->tot_len),
ntohl(tcp->seq), ntohl(tcp->ack_seq),
(tcp->fin) ? " FIN" : "",
(tcp->syn) ? " SYN" : "",
(tcp->rst) ? " RST" : "",
(tcp->psh) ? " PUSH" : "",
(tcp->ack) ? " ACK" : "",
(tcp->urg) ? " URG" : "",
saddr, sport, daddr, dport);
} else {
syslog(LOG_INFO,
"filter %s rule %d proto %d len %d packet %s,%d => %s,%d",
(accept)?"accepted":"ignored",rule,
pkt->protocol,
htons(pkt->tot_len),
saddr, sport, daddr, dport);
}
}
/* Check if we need to reorder IP addresses for cannonical ordering */
static int ip_direction(struct iphdr *pkt)
{
struct udphdr *udp = (struct udphdr *)((char *)pkt + 4*pkt->ihl);
if (ntohl(pkt->saddr) > ntohl(pkt->daddr)
|| (ntohl(pkt->saddr) == ntohl(pkt->daddr) &&
(pkt->protocol == IPPROTO_TCP || pkt->protocol == IPPROTO_UDP)
&& ntohs(udp->source) > ntohs(udp->dest)))
return 2;
else
return 1;
}
static void ip_swap_addrs(struct iphdr *pkt)
{
struct udphdr *udp = (struct udphdr *)((char *)pkt + 4*pkt->ihl);
unsigned long taddr;
unsigned short tport;
if (pkt->protocol == IPPROTO_TCP || pkt->protocol == IPPROTO_UDP) {
tport = udp->source;
udp->source = udp->dest;
udp->dest = tport;
}
taddr = pkt->saddr;
pkt->saddr = pkt->daddr;
pkt->daddr = taddr;
}
void print_filter(FW_Filter *filter)
{
int i;
syslog(LOG_INFO,"filter: prl %d log %d type %d cnt %d tm %d",
filter->prule,filter->log,filter->type,
filter->count,filter->timeout);
for (i = 0; i < filter->count; i++) {
syslog(LOG_INFO," term: shift %d op %d off %d%c msk %x tst %x",
filter->terms[i].shift, filter->terms[i].op,
filter->terms[i].offset&0x7f,
(filter->terms[i].offset&0x80)?'d':'h',
filter->terms[i].mask, filter->terms[i].test);
}
}
__u16 checksum(__u16 *buf, int nwords)
{
unsigned long sum;
/* WARNING: possible endianess assumptions here! */
for (sum = 0; nwords > 0; nwords--)
sum += *buf++;
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16);
return ~sum ;
}
void forge_tcp_reset(struct iphdr *iph, int len)
{
struct tcphdr *tcph,*ntcph;
struct iphdr *niph;
struct pseudo {
__u32 saddr;
__u32 daddr;
__u8 zero;
__u8 ptcl;
__u16 len;
} *pseudo;
tcph = (struct tcphdr *)((char *)iph + 4*iph->ihl);
if (iph == 0 || iph->frag_off&htons(0x1fff) || tcph->rst)
return;
niph = malloc(sizeof(struct tcphdr)+sizeof(struct iphdr)
+sizeof(struct pseudo));
if (niph == 0) return;
niph->ihl = 5; /* Header length in octets. */
niph->tot_len = htons(sizeof(struct tcphdr)+sizeof(struct iphdr));
niph->version = 4;
niph->tos = (iph->tos & 0x1E) | 0xC0;
niph->id = iph->id;
niph->frag_off = 0;
niph->ttl = 16;
niph->protocol = IPPROTO_TCP;
niph->saddr = iph->daddr; /* We may be lying. Shrugh. */
niph->daddr = iph->saddr; /* Were we sent the reject message */
niph->check = 0;
niph->check = checksum((__u16 *)niph, sizeof(struct iphdr)>>1);
/* We should also be copying the ip options at this point.
* (More major barf bag material.)
*/
ntcph = (struct tcphdr *)((char *)niph + sizeof(struct iphdr));
ntcph->source = tcph->dest;
ntcph->dest = tcph->source;
ntcph->res1 = 0;
ntcph->res2 = 0;
ntcph->doff = sizeof(struct tcphdr)/4;
ntcph->fin = 0;
ntcph->syn = 0;
ntcph->rst = 1;
ntcph->psh = 0;
ntcph->urg = 0;
ntcph->window = 0;
ntcph->urg_ptr = 0;
if (tcph->ack) {
ntcph->ack = 0;
ntcph->seq = tcph->ack_seq;
ntcph->ack_seq = 0;
} else {
ntcph->ack = 1;
ntcph->seq = 0;
if (!tcph->syn)
ntcph->ack_seq = tcph->seq;
else
ntcph->ack_seq = htonl(ntohl(tcph->seq)+1);
}
pseudo = (struct pseudo*)(ntcph + 1);
pseudo->saddr = niph->saddr;
pseudo->daddr = niph->daddr;
pseudo->zero = 0;
pseudo->ptcl = niph->protocol;
pseudo->len = ntohs(sizeof(struct tcphdr));
ntcph->check = 0;
ntcph->check = checksum((__u16 *)ntcph,(sizeof(struct tcphdr)+sizeof(struct pseudo))>>1);
/*
* OK, send the packet now.
*/
send_packet((unsigned char *)niph,sizeof(struct tcphdr)+sizeof(struct iphdr));
free((void *)niph);
}
/* Check if a packet passes the filters */
int check_firewall(int unitnum, unsigned char *pkt, int len)
{
FW_unit *unit;
FW_Filters *fw;
unsigned char *data;
FW_ProtocolRule *prule, *pprule = 0;
FW_Term *term;
int i,v,rule;
int direction,opdir;
TCP_STATE lflags;
clock_t clock = time(0);
FW_ID id;
FW_Connection *conn;
struct iphdr * ip_pkt = (struct iphdr *)pkt;
memset(&lflags,0,sizeof(lflags));
if (!initialized) init_units();
if (unitnum < 0 || unitnum >= FW_NRUNIT) {
/* FIXME: set an errorno? */
return -1;
}
unit = &units[unitnum];
fw = unit->filters;
data = pkt + 4*((struct iphdr *)pkt)->ihl;
/* Find the correct protocol rule */
for (i = 0; i < unit->nrules; i++) {
pprule = &unit->prules[i];
if (FW_PROTO_ALL(pprule->protocol)
|| pprule->protocol == ip_pkt->protocol)
break;
}
if (pprule == 0) {
return -1; /* No protocol rules? */
}
/* If we have the "strict-forwarding" option set then unless one of
* the two addresses matches the local address we should ignore it.
*/
if (strict_forwarding && ip_pkt->saddr != local_addr && ip_pkt->daddr != local_addr) {
/* We forge resets for TCP protocol stuff that has been
* shut down do to a link failure.
*/
if (ip_pkt->protocol == IPPROTO_TCP)
forge_tcp_reset(ip_pkt,len);
goto skip;
}
/* Build the connection ID, and set the direction flag */
direction = ip_direction(ip_pkt);
if (direction == 2) ip_swap_addrs(ip_pkt);
memset(&id,0,sizeof(id));
for (i = 0; i < FW_ID_LEN; i++)
id.id[i] = (FW_IN_DATA(pprule->codes[i])?data:pkt)
[FW_OFFSET(pprule->codes[i])];
if (direction == 2) ip_swap_addrs(ip_pkt);
conn = find_connection(unit,&id);
opdir = (direction==1)?2:1;
/* Do the TCP liveness changes */
if (ip_pkt->protocol == IPPROTO_TCP) {
struct tcphdr *tcp = (struct tcphdr *)((char *)ip_pkt + 4*ip_pkt->ihl);
int tcp_data_len = len - (4*ip_pkt->ihl + sizeof(struct tcphdr));
if (conn) {
lflags = conn->tcp_state;
} else {
lflags.fin_seq[0] = lflags.fin_seq[1] = 0;
lflags.tcp_flags = 0;
lflags.saw_fin = 0;
}
if (tcp->rst) {
lflags.saw_fin = 0;
lflags.tcp_flags = 0;
} else if (tcp->fin) {
lflags.saw_fin |= direction;
lflags.fin_seq[direction-1] = ntohl(tcp->seq)+tcp_data_len+1;
} else if (tcp->syn || tcp_data_len > 0) {
/* Either we have a SYN packet, or we have a data carrying
* packet. In either case we want to declare this direction live.
* FIXME. It is possible that this should set saw_fin to 0 in the
* case that we have a SYN packet.
*/
lflags.saw_fin &= ~direction;
lflags.tcp_flags |= direction;
}
if ((lflags.saw_fin & opdir) && (tcp->ack)) {
if (lflags.fin_seq[opdir-1] == ntohl(tcp->ack_seq)) {
lflags.tcp_flags &= ~direction;
}
}
if (conn) {
conn->tcp_state = lflags;
}
}
rule = 1;
while (fw) {
#ifdef 0
print_filter(&fw->filt);
#endif
/* is this rule currently applicable? */
if ((unit->up && fw->filt.type == FW_TYPE_BRINGUP)
|| (!unit->up && fw->filt.type == FW_TYPE_KEEPUP)
|| !in_slot(fw->filt.times,&clock)
|| fw->filt.type == FW_TYPE_IMPULSE
|| fw->filt.type == FW_TYPE_UP
|| fw->filt.type == FW_TYPE_DOWN)
goto next_rule;
/* Check the protocol rule */
prule = &unit->prules[fw->filt.prule];
if (!(FW_PROTO_ALL(prule->protocol)
|| prule->protocol == ip_pkt->protocol))
goto next_rule;
/* Check the terms */
for (i = 0;
(fw->filt.count > FW_MAX_TERMS) || (i < fw->filt.count); i++) {
if (i > FW_MAX_TERMS && fw->filt.count == 0) {
fw = fw->next, i = 0;
if (fw == NULL) break;
}
term = &fw->filt.terms[i];
if (FW_TCP_STATE(term->offset))
v = (lflags.tcp_flags >> term->shift) && term->mask;
else
v = (ntohl(*(int *)(&(FW_IN_DATA(term->offset)?data:pkt)
[FW_OFFSET(term->offset)]))
>> term->shift) & term->mask;
#ifdef 0
syslog(LOG_INFO,"testing ip %x:%x data %x:%x mask %x shift %x test %x v %x",
ntohl(*(int *)(&pkt[FW_OFFSET(term->offset)])),
*(int *)(&pkt[FW_OFFSET(term->offset)]),
ntohl(*(int *)(&data[FW_OFFSET(term->offset)])),
*(int *)(&data[FW_OFFSET(term->offset)]),
term->mask,
term->shift,
term->test,
v);
#endif
switch (term->op) {
case FW_EQ: if (v != term->test) goto next_rule; break;
case FW_NE: if (v == term->test) goto next_rule; break;
case FW_GE: if (v < term->test) goto next_rule; break;
case FW_LE: if (v > term->test) goto next_rule; break;
}
}
/* Ok, we matched a rule. What are we suppose to do? */
#ifdef 0
if (fw->filt.log)
#endif
if (debug&DEBUG_FILTER_MATCH)
log_packet(fw->filt.type!=FW_TYPE_IGNORE,ip_pkt,len,rule);
/* Check if this entry goes into the queue or not */
if (fw->filt.type != FW_TYPE_IGNORE && fw->filt.type != FW_TYPE_WAIT) {
add_connection(
unit,
conn,
&id,
fw->filt.timeout,
lflags);
}
/* check if we are no longer waiting */
if (fw->filt.type == FW_TYPE_WAIT) {
unit->waiting = 0;
/* WAITING rules don't do the final match, but
* must occur before other rules
*/
goto next_rule;
}
/* Return 1 if accepting rule with non zero timeout, 0 otherwise */
return ((fw->filt.type != FW_TYPE_IGNORE || fw->filt.type != FW_TYPE_WAIT) && fw->filt.timeout > 0);
next_rule: /* try the next filter */
fw = fw->next;
rule++;
}
skip:
/* Failed to match any rule. This means we ignore the packet */
if (debug&DEBUG_FILTER_MATCH)
log_packet(0,ip_pkt,len,0);
return 1;
}
static void pcountdown(int level, long secs)
{
char buf[10];
/* Make sure that we don't try to print values that overflow our buffer */
if (secs < 0) secs = 0;
if (secs > 359999) secs = 359999;
sprintf(buf,"%02ld:%02ld:%02ld\n",secs/3600,(secs/60)%60,secs%60);
if (monitors) mon_write(level,buf,9);
}
int ctl_firewall(int op, struct firewall_req *req)
{
FW_unit *unit;
if (!initialized) init_units();
/* Need to check that req is OK */
if (req && req->unit >= FW_NRUNIT) return -1; /* ERRNO */
if (req) unit = &units[req->unit];
else unit = units;
switch (op) {
case IP_FW_QFLUSH:
if (!req) return -1; /* ERRNO */
{
FW_Connection *c,*cn;
for (c = unit->connections->next;
c != unit->connections; c = cn) {
cn = c->next;
del_timer(&c->timer);
c->next->prev = c->prev;
c->prev->next = c->next;
free((void *)c);
}
return 0;
}
case IP_FW_QCHECK:
if (!req) return -1; /* ERRNO */
fw_force_update(unit);
fw_impulse_update(unit,0);
return (unit->force == 2
|| (unit->force == 0
&& !(unit->up && unit->impulse_mode == 0
&& (impulse_init_time > 0 || impulse_time > 0))
&& unit->connections == unit->connections->next));
case IP_FW_PFLUSH:
if (!req) return -1; /* ERRNO */
unit->nrules = 0;
return 0;
/* PFLUSH implies FFLUSH */
case IP_FW_FFLUSH:
if (!req) return -1; /* ERRNO */
{
FW_Filters *next, *filt = unit->filters;
while (filt)
{ next = filt->next; free(filt); filt = next; }
unit->filters = NULL;
unit->last = NULL;
}
return 0;
case IP_FW_AFILT:
if (!req) return -1; /* ERRNO */
{
FW_Filters *filters = malloc(sizeof(FW_Filters));
if (filters == 0) {
syslog(LOG_ERR,"Out of memory! AIIEEE!");
return -1; /* ERRNO */
}
filters->next = 0;
filters->filt = req->fw_arg.filter;
if (unit->last) unit->last->next = filters;
if (!unit->filters) unit->filters = filters;
unit->last = filters;
unit->nfilters++;
}
return 0;
case IP_FW_APRULE:
if (!req) return -1; /* ERRNO */
if (unit->nrules >= FW_MAX_PRULES) return -1; /* ERRNO */
unit->prules[(int)unit->nrules] = req->fw_arg.rule;
return unit->nrules++;
/* Printing does nothing right now */
case IP_FW_PCONN:
if (!req) return -1; /* ERRNO */
{
unsigned long atime = time(0);
unsigned long tstamp = timestamp();
FW_Connection *c;
char saddr[20], daddr[20];
struct in_addr addr;
syslog(LOG_INFO,"up = %d, forcing = %d, impulse = %d, iitime = %d, itime = %d, ifuzz = %d, itimeout = %ld, timeout = %ld, next alarm = %d",
unit->up,unit->force, unit->impulse_mode, impulse_init_time, impulse_time,
impulse_fuzz,
unit->impulse.expected-tstamp,unit->force_etime-atime,
next_alarm());
for (c=unit->connections->next; c!=unit->connections; c=c->next) {
if (c->timer.next == 0) c->timer.expected = tstamp;
addr.s_addr = c->id.id[1] + (c->id.id[2]<<8)
+ (c->id.id[3]<<16) + (c->id.id[4]<<24);
strcpy(saddr,inet_ntoa(addr));
addr.s_addr = c->id.id[5] + (c->id.id[6]<<8)
+ (c->id.id[7]<<16) + (c->id.id[8]<<24);
strcpy(daddr,inet_ntoa(addr));
syslog(LOG_INFO,
"ttl %ld, %d - %s/%d => %s/%d (tcp state ([%lx,%lx] %d,%d))",
c->timer.expected-tstamp, c->id.id[0],
saddr, c->id.id[10]+(c->id.id[9]<<8),
daddr, c->id.id[12]+(c->id.id[11]<<8),
c->tcp_state.fin_seq[0],
c->tcp_state.fin_seq[1],
c->tcp_state.saw_fin,
c->tcp_state.tcp_flags);
}
return 0;
}
return 0;
case IP_FW_MCONN:
if (!req || !monitors) return -1; /* ERRNO */
{
unsigned long atime = time(0);
unsigned long tstamp = timestamp();
FW_Connection *c;
char saddr[20], daddr[20];
int sport, dport;
char proto[20];
char *pent;
struct in_addr addr;
char buf[1024];
sprintf(buf,"STATUS\n%d\n%d\n%d\n%d\n%d\n%d\n%d\n%d\n",
unit->up, unit->force, unit->impulse_mode,
impulse_init_time, impulse_time,
impulse_fuzz, blocked, forced);
if (monitors) mon_write(MONITOR_STATUS,buf,strlen(buf));
/* If this is non-zero we just have an expired timer so
* we of course display nothing.
*/
if (unit->impulse.expected-tstamp > 0)
pcountdown(MONITOR_STATUS,unit->impulse.expected-tstamp);
else
pcountdown(MONITOR_STATUS,0);
pcountdown(MONITOR_STATUS,unit->force_etime-atime);
pcountdown(MONITOR_STATUS,next_alarm());
if (monitors) mon_write(MONITOR_QUEUE,"QUEUE\n",6);
for (c=unit->connections->next; c!=unit->connections; c=c->next) {
if (c->timer.next == 0) continue;
addr.s_addr = c->id.id[1] + (c->id.id[2]<<8)
+ (c->id.id[3]<<16) + (c->id.id[4]<<24);
strcpy(saddr,inet_ntoa(addr));
addr.s_addr = c->id.id[5] + (c->id.id[6]<<8)
+ (c->id.id[7]<<16) + (c->id.id[8]<<24);
strcpy(daddr,inet_ntoa(addr));
pent = getprotonumber(c->id.id[0]);
if (pent) strcpy(proto,pent);
else sprintf(proto,"%d",c->id.id[0]);
sport = c->id.id[10]+(c->id.id[9]<<8);
dport = c->id.id[12]+(c->id.id[11]<<8);
sprintf(buf,
"%-4s %15s/%-5d %15s/%-5d ",
proto, saddr, sport,
daddr, dport);
if (monitors) mon_write(MONITOR_QUEUE,buf,strlen(buf));
pcountdown(MONITOR_QUEUE,c->timer.expected-tstamp);
}
if (monitors) mon_write(MONITOR_QUEUE,"END QUEUE\n",10);
return 0;
}
return 0;
case IP_FW_PPRULE:
if (!req) return -1; /* ERRNO */
return 0;
case IP_FW_PFILT:
if (!req) return -1; /* ERRNO */
return 0;
/* Opening and closing firewalls is cooperative right now.
* Also, it does nothing to change the behavior of a device
* associated with the firewall.
*/
case IP_FW_OPEN:
{
int i;
for (i = 0; i < FW_NRUNIT; i++)
if (units[i].used == 0) {
struct firewall_req mreq;
mreq.unit = i;
ctl_firewall(IP_FW_PFLUSH,&mreq);
units[i].used = 1;
units[i].force_etime = 0;
units[i].impulse_etime = 0;
units[i].waiting = 1;
return i;
}
return -1; /* ERRNO */
}
case IP_FW_CLOSE:
{
struct firewall_req mreq;
if (!req) return -1; /* ERRNO */
mreq.unit = req->unit;
ctl_firewall(IP_FW_PFLUSH,&mreq);
unit->used = 0;
return 0;
}
case IP_FW_UP:
unit->up = 1;
run_ip_up();
fw_force_update(unit);
fw_impulse_update(unit,1);
return 0;
case IP_FW_DOWN:
if (unit->up) run_ip_down();
unit->up = 0;
/* turn off the impulse generator */
del_timer(&unit->impulse);
unit->impulse_mode = 1;
impulse_init_time = 0;
return 0;
case IP_FW_WAIT:
return unit->waiting;
case IP_FW_RESET_WAITING:
unit->waiting = 1;
return 0;
}
return -1; /* ERRNO */
}
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