/* Create the fwknop custom chains (at least those that are configured).
*/
static int
create_fw_chains(const fko_srv_options_t * const opts)
{
int i, got_err = 0;
for(i=0; i<(NUM_FWKNOP_ACCESS_TYPES); i++)
{
if(fwc.chain[i].target[0] == '\0')
continue;
if(chain_exists(opts, i) == 0)
{
/* Create the chain
*/
if(! EXTCMD_IS_SUCCESS(create_chain(opts, i)))
got_err++;
/* Then create the jump rule to that chain if it
* doesn't already exist (which is possible)
*/
if(jump_rule_exists(opts, i) == 0)
if(! EXTCMD_IS_SUCCESS(add_jump_rule(opts, i)))
got_err++;
}
}
return(got_err);
}
int
fw_cleanup(void)
{
int res, got_err = 0;
zero_cmd_buffers();
if(fwc.active_set_num > 0
&& ipfw_set_exists(fwc.fw_command, fwc.active_set_num))
{
/* Create the set delete command for active rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_DEL_RULE_SET_ARGS,
fwc.fw_command,
fwc.active_set_num
);
//printf("CMD: '%s'\n", cmd_buf);
res = system(cmd_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
/* --DSS Keep expired rule list so any existing established
are not lost */
#if 0
if(fwc.expire_set_num > 0)
{
/* Create the set delete command for expired rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_DEL_RULE_SET_ARGS,
fwc.fw_command,
fwc.expire_set_num
);
//printf("CMD: '%s'\n", cmd_buf);
res = system(cmd_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
#endif
/* Free the rule map.
*/
if(fwc.rule_map != NULL)
free(fwc.rule_map);
return(got_err);
}
/* Check to see if the fwknop anchor is linked into the main policy. If not,
* any rules added/deleted by fwknopd will have no effect on real traffic.
*/
static int
anchor_active(const fko_srv_options_t *opts)
{
int res = 0;
char anchor_search_str[MAX_PF_ANCHOR_SEARCH_LEN] = {0};
/* Build our anchor search string
*/
snprintf(anchor_search_str, MAX_PF_ANCHOR_SEARCH_LEN-1, "%s\n",
opts->fw_config->anchor);
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " PF_ANCHOR_CHECK_ARGS,
opts->fw_config->fw_command
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
return 0;
}
/* Check to see if the anchor exists and is linked into the main policy
*/
if(strstr(cmd_out, anchor_search_str) == NULL)
return 0;
return 1;
}
static int
add_jump_rule(const fko_srv_options_t *opts, const int chain_num)
{
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_JUMP_RULE_ARGS,
fwc.fw_command,
fwc.chain[chain_num].table,
fwc.chain[chain_num].from_chain,
fwc.chain[chain_num].jump_rule_pos,
fwc.chain[chain_num].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "add_jump_rule() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
log_msg(LOG_INFO, "Added jump rule from chain: %s to chain: %s",
fwc.chain[chain_num].from_chain,
fwc.chain[chain_num].to_chain);
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
return res;
}
static int
chain_exists(const fko_srv_options_t * const opts, const int chain_num)
{
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_CHAIN_EXISTS_ARGS,
fwc.fw_command,
fwc.chain[chain_num].table,
fwc.chain[chain_num].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "chain_exists() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
log_msg(LOG_DEBUG, "'%s' table '%s' chain exists",
fwc.chain[chain_num].table,
fwc.chain[chain_num].to_chain);
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
return res;
}
static int
ipfw_set_exists(const fko_srv_options_t *opts,
const char *fw_command, const unsigned short set_num)
{
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_SET_RULES_ARGS,
fw_command,
set_num
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "ipfw_set_exists() CMD: '%s' (res: %d)",
cmd_buf, res);
if(!EXTCMD_IS_SUCCESS(res))
return(0);
if(cmd_out[0] == '\0')
return(0);
return(1);
}
/* Print all firewall rules currently instantiated by the running fwknopd
* daemon to stdout.
*/
int
fw_dump_rules(const fko_srv_options_t *opts)
{
int res, got_err = 0;
printf("Listing fwknopd pf rules...\n");
zero_cmd_buffers();
/* Create the list command for active rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " PF_LIST_ANCHOR_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->anchor
);
printf("\nActive Rules in PF anchor '%s':\n", opts->fw_config->anchor);
res = system(cmd_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
return(got_err);
}
static int
add_jump_rule(const fko_srv_options_t * const opts, const int chain_num)
{
int res = 0, rv = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_JUMP_RULE_ARGS,
fwc.fw_command,
fwc.chain[chain_num].table,
fwc.chain[chain_num].from_chain,
fwc.chain[chain_num].jump_rule_pos,
fwc.chain[chain_num].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
log_msg(LOG_DEBUG, "add_jump_rule() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added jump rule from chain: %s to chain: %s",
fwc.chain[chain_num].from_chain,
fwc.chain[chain_num].to_chain);
rv = 1;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
return rv;
}
static int
rule_exists_chk_support(const fko_srv_options_t * const opts,
const char * const chain, const char * const rule)
{
int rule_exists = 0;
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_CHK_RULE_ARGS,
opts->fw_config->fw_command, chain, rule);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "rule_exists_chk_support() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res) && strlen(err_buf))
{
log_msg(LOG_DEBUG, "rule_exists_chk_support() Rule : '%s' in %s does not exist",
rule, chain);
}
else
{
rule_exists = 1;
log_msg(LOG_DEBUG, "rule_exists_chk_support() Rule : '%s' in %s already exists",
rule, chain);
}
return(rule_exists);
}
static int
create_rule(const fko_srv_options_t * const opts,
const char * const fw_chain, const char * const fw_rule)
{
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s -A %s %s",
opts->fw_config->fw_command, fw_chain, fw_rule);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, WANT_STDERR,
NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "create_rule() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_DEBUG, "create_rule() Rule: '%s' added to %s",
fw_rule, fw_chain);
res = 1;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
return res;
}
static int
create_chain(const fko_srv_options_t * const opts, const int chain_num)
{
int res = 0, rv = 0;
zero_cmd_buffers();
/* Create the custom chain.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_NEW_CHAIN_ARGS,
fwc.fw_command,
fwc.chain[chain_num].table,
fwc.chain[chain_num].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, WANT_STDERR,
NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "create_chain() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(EXTCMD_IS_SUCCESS(res))
rv = 1;
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
return rv;
}
/* Create the fwknop custom chains (at least those that are configured).
*/
static int
create_fw_chains(const fko_srv_options_t *opts)
{
int i;
int res, got_err = 0;
for(i=0; i<(NUM_FWKNOP_ACCESS_TYPES); i++)
{
if(fwc.chain[i].target[0] == '\0')
continue;
zero_cmd_buffers();
/* Create the custom chain.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_NEW_CHAIN_ARGS,
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "create_fw_chains() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
/* Then create the jump rule to that chain.
*/
res = add_jump_rule(opts, i);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
got_err++;
}
return(got_err);
}
/* Print all firewall rules currently instantiated by the running fwknopd
* daemon to stdout.
*/
int
fw_dump_rules(fko_srv_options_t *opts)
{
int res, got_err = 0;
zero_cmd_buffers();
/* Create the list command for active rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->active_set_num
);
//printf("(%i) CMD: '%s'\n", i, cmd_buf);
printf("\nActive Rules:\n");
res = system(cmd_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
/* Create the list command for expired rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->expire_set_num
);
//printf("(%i) CMD: '%s'\n", i, cmd_buf);
printf("\nExpired Rules:\n");
res = system(cmd_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
return(got_err);
}
static void
delete_all_anchor_rules(const fko_srv_options_t *opts)
{
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " PF_DEL_ALL_ANCHOR_RULES,
fwc.fw_command,
fwc.anchor
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
return;
}
static int
ipfw_set_exists(const char *fw_command, const unsigned short set_num)
{
int res = 0;
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_SET_RULES_ARGS,
fw_command,
set_num
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if(!EXTCMD_IS_SUCCESS(res))
return(0);
if(cmd_out[0] == '\0')
return(0);
return(1);
}
/* Iterate over the current rule set and purge expired
* firewall rules.
*/
void
check_firewall_rules(const fko_srv_options_t *opts)
{
char exp_str[12];
char rule_num_str[6];
char *ndx, *rn_start, *rn_end, *tmp_mark;
int i=0, res=0;
time_t now, rule_exp, min_exp = 0;
unsigned short curr_rule;
/* Just in case we somehow lose track and fall out-of-whack.
*/
if(fwc.active_rules > fwc.max_rules)
fwc.active_rules = 0;
/* If there are no active rules or we have not yet
* reached our expected next expire time, continue.
*/
if(fwc.active_rules == 0)
return;
time(&now);
if (fwc.next_expire > now)
return;
zero_cmd_buffers();
/* There should be a rule to delete. Get the current list of
* rules for this chain and delete the ones that are expired.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_SET_RULES_ARGS,
opts->fw_config->fw_command,
fwc.active_set_num
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "check_firewall_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
return;
}
if(opts->verbose > 1)
log_msg(LOG_INFO, "RULES LIST: %s", cmd_out);
/* Find the first _exp_ string (if any).
*/
ndx = strstr(cmd_out, EXPIRE_COMMENT_PREFIX);
if(ndx == NULL)
{
/* we did not find an expected rule.
*/
log_msg(LOG_ERR,
"Did not find expire comment in rules list %i.\n", i);
if (fwc.active_rules > 0)
fwc.active_rules--;
return;
}
/* Walk the list and process rules as needed.
*/
while (ndx != NULL) {
/* Jump forward and extract the timestamp
*/
ndx += strlen(EXPIRE_COMMENT_PREFIX);
/* remember this spot for when we look for the next
* rule.
*/
tmp_mark = ndx;
strlcpy(exp_str, ndx, 11);
rule_exp = (time_t)atoll(exp_str);
if(rule_exp <= now)
{
/* Backtrack and get the rule number and delete it.
*/
rn_start = ndx;
while(--rn_start > cmd_out)
{
if(*rn_start == '\n')
break;
}
if(*rn_start == '\n')
{
rn_start++;
}
else if(rn_start > cmd_out)
{
/* This should not happen. But if it does, complain,
* decrement the active rule value, and go on.
*/
log_msg(LOG_ERR,
"Rule parse error while finding rule line start.");
if (fwc.active_rules > 0)
fwc.active_rules--;
break;
}
rn_end = strchr(rn_start, ' ');
if(rn_end == NULL)
{
/* This should not happen. But if it does, complain,
* decrement the active rule value, and go on.
*/
log_msg(LOG_ERR,
"Rule parse error while finding rule number.");
if (fwc.active_rules > 0)
fwc.active_rules--;
break;
}
strlcpy(rule_num_str, rn_start, (rn_end - rn_start)+1);
curr_rule = atoi(rule_num_str);
zero_cmd_buffers();
/* Move the rule to the expired rules set.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_MOVE_RULE_ARGS,
opts->fw_config->fw_command,
curr_rule,
fwc.expire_set_num
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "check_firewall_rules() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Moved rule %s with expire time of %u to set %u.",
rule_num_str, rule_exp, fwc.expire_set_num
);
if (fwc.active_rules > 0)
fwc.active_rules--;
fwc.rule_map[curr_rule - fwc.start_rule_num] = RULE_EXPIRED;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
else
{
/* Track the minimum future rule expire time.
*/
if(rule_exp > now)
min_exp = (min_exp < rule_exp) ? min_exp : rule_exp;
}
/* Push our tracking index forward beyond (just processed) _exp_
* string so we can continue to the next rule in the list.
*/
ndx = strstr(tmp_mark, EXPIRE_COMMENT_PREFIX);
}
/* Set the next pending expire time accordingly. 0 if there are no
* more rules, or whatever the next expected (min_exp) time will be.
*/
if(fwc.active_rules < 1)
fwc.next_expire = 0;
else if(min_exp)
fwc.next_expire = min_exp;
}
int
fw_cleanup(const fko_srv_options_t *opts)
{
int res, got_err = 0;
if(strncasecmp(opts->config[CONF_FLUSH_IPFW_AT_EXIT], "N", 1) == 0)
{
if(fwc.rule_map != NULL)
free(fwc.rule_map);
return(0);
}
zero_cmd_buffers();
if(fwc.active_set_num > 0
&& ipfw_set_exists(opts, fwc.fw_command, fwc.active_set_num))
{
/* Create the set delete command for active rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_DEL_RULE_SET_ARGS,
fwc.fw_command,
fwc.active_set_num
);
res = system(cmd_buf);
if (opts->verbose)
log_msg(LOG_INFO, "fw_cleanup() CMD: '%s' (res: %d)",
cmd_buf, res);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
/* --DSS Keep expired rule list so any existing established
are not lost */
#if 0
if(fwc.expire_set_num > 0)
{
/* Create the set delete command for expired rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_DEL_RULE_SET_ARGS,
fwc.fw_command,
fwc.expire_set_num
);
//printf("CMD: '%s'\n", cmd_buf);
res = system(cmd_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
#endif
/* Free the rule map.
*/
if(fwc.rule_map != NULL)
free(fwc.rule_map);
return(got_err);
}
/* Rule Processing - Create an access request...
*/
int
process_spa_request(const fko_srv_options_t *opts, const acc_stanza_t *acc, spa_data_t *spadat)
{
unsigned short rule_num;
acc_port_list_t *port_list = NULL;
acc_port_list_t *ple;
unsigned int fst_proto;
unsigned int fst_port;
int res = 0;
time_t now;
unsigned int exp_ts;
/* Parse and expand our access message.
*/
expand_acc_port_list(&port_list, spadat->spa_message_remain);
/* Start at the top of the proto-port list...
*/
ple = port_list;
/* Remember the first proto/port combo in case we need them
* for NAT access requests.
*/
fst_proto = ple->proto;
fst_port = ple->port;
/* Set our expire time value.
*/
time(&now);
exp_ts = now + spadat->fw_access_timeout;
/* For straight access requests, we currently support multiple proto/port
* request.
*/
if(spadat->message_type == FKO_ACCESS_MSG
|| spadat->message_type == FKO_CLIENT_TIMEOUT_ACCESS_MSG)
{
/* Pull the next available rule number.
*/
rule_num = get_next_rule_num();
/* If rule_num comes back as 0, we aready have the maximum number
* of active rules allowed so we reject and bail here.
*/
if(rule_num == 0)
{
log_msg(LOG_WARNING, "Access request rejected: Maximum allowed number of rules has been reached.");
return(-1);
}
/* Create an access command for each proto/port for the source ip.
*/
while(ple != NULL)
{
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_ADD_RULE_ARGS,
fwc.fw_command,
rule_num,
fwc.active_set_num,
ple->proto,
spadat->use_src_ip,
ple->port,
exp_ts
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added Rule %u for %s, %s expires at %u",
rule_num,
spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
fwc.rule_map[rule_num - fwc.start_rule_num] = RULE_ACTIVE;
fwc.active_rules++;
fwc.total_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(fwc.next_expire < now || exp_ts < fwc.next_expire)
fwc.next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
ple = ple->next;
}
}
else
{
/* No other SPA request modes are supported yet.
*/
if(spadat->message_type == FKO_LOCAL_NAT_ACCESS_MSG
|| spadat->message_type == FKO_CLIENT_TIMEOUT_LOCAL_NAT_ACCESS_MSG)
{
log_msg(LOG_WARNING, "Local NAT requests are not currently supported.");
}
else if(spadat->message_type == FKO_NAT_ACCESS_MSG
|| spadat->message_type == FKO_CLIENT_TIMEOUT_NAT_ACCESS_MSG)
{
log_msg(LOG_WARNING, "Forwarding/NAT requests are not currently supported.");
}
return(-1);
}
return(res);
}
void
fw_initialize(const fko_srv_options_t *opts)
{
int res = 0;
unsigned short curr_rule;
char *ndx;
/* For now, we just call fw_cleanup to start with clean slate.
*/
if(strncasecmp(opts->config[CONF_FLUSH_IPFW_AT_INIT], "Y", 1) == 0)
res = fw_cleanup(opts);
if(res != 0)
{
fprintf(stderr, "Fatal: Errors detected during ipfw rules initialization.\n");
exit(EXIT_FAILURE);
}
/* Allocate our rule_map array for tracking active (and expired) rules.
*/
fwc.rule_map = calloc(fwc.max_rules, sizeof(char));
if(fwc.rule_map == NULL)
{
fprintf(stderr, "Fatal: Memory allocation error in fw_initialize.\n");
exit(EXIT_FAILURE);
}
/* Create a check-state rule if necessary.
*/
if(strncasecmp(opts->config[CONF_IPFW_ADD_CHECK_STATE], "Y", 1) == 0)
{
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_ADD_CHECK_STATE_ARGS,
fwc.fw_command,
fwc.start_rule_num,
fwc.active_set_num
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "fw_initialize() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added check-state rule %u to set %u",
fwc.start_rule_num,
fwc.active_set_num
);
fwc.rule_map[0] = RULE_ACTIVE;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
if(fwc.expire_set_num > 0
&& (strncasecmp(opts->config[CONF_FLUSH_IPFW_AT_INIT], "Y", 1) == 0))
{
/* Make sure our expire set is disabled.
*/
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_DISABLE_SET_ARGS,
fwc.fw_command,
fwc.expire_set_num
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "fw_initialize() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
log_msg(LOG_INFO, "Set ipfw expire set %u to disabled.",
fwc.expire_set_num);
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
/* Now read the expire set in case there are existing
* rules to track.
*/
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_EXP_SET_RULES_ARGS,
opts->fw_config->fw_command,
fwc.expire_set_num
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "fw_initialize() CMD: '%s' (res: %d)",
cmd_buf, res);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
return;
}
if(opts->verbose > 1)
log_msg(LOG_INFO, "RULES LIST: %s", cmd_out);
/* Find the first "# DISABLED" string (if any).
*/
ndx = strstr(cmd_out, "# DISABLED ");
/* Assume no disabled rules if we did not see the string.
*/
if(ndx == NULL)
return;
/* Otherwise we walk each line to pull the rule number and
* set the appropriate rule map entries.
*/
while(ndx != NULL)
{
/* Skip over the DISABLED string to the rule num.
*/
ndx += 11;
if(isdigit(*ndx))
{
curr_rule = atoi(ndx);
if(curr_rule >= fwc.start_rule_num
&& curr_rule < fwc.start_rule_num + fwc.max_rules)
{
fwc.rule_map[curr_rule - fwc.start_rule_num] = RULE_EXPIRED;
fwc.total_rules++;
}
}
else
log_msg(LOG_WARNING, "fw_initialize: No rule number found where expected.");
/* Find the next "# DISABLED" string (if any).
*/
ndx = strstr(ndx, "# DISABLED ");
}
}
/* Iterate over the configure firewall access chains and purge expired
* firewall rules.
*/
void
check_firewall_rules(const fko_srv_options_t * const opts)
{
char exp_str[12] = {0};
char rule_num_str[6] = {0};
char *ndx, *rn_start, *rn_end, *tmp_mark;
int i, res, rn_offset, rule_num, is_err;
time_t now, rule_exp, min_exp = 0;
struct fw_chain *ch = opts->fw_config->chain;
time(&now);
/* Iterate over each chain and look for active rules to delete.
*/
for(i=0; i < NUM_FWKNOP_ACCESS_TYPES; i++)
{
/* If there are no active rules or we have not yet
* reached our expected next expire time, continue.
*/
if(ch[i].active_rules == 0 || ch[i].next_expire > now)
continue;
zero_cmd_buffers();
rn_offset = 0;
/* There should be a rule to delete. Get the current list of
* rules for this chain and delete the ones that are expired.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_LIST_RULES_ARGS,
opts->fw_config->fw_command,
ch[i].table,
ch[i].to_chain
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(cmd_out);
log_msg(LOG_DEBUG, "check_firewall_rules() CMD: '%s' (res: %d, cmd_out: %s)",
cmd_buf, res, cmd_out);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
continue;
}
log_msg(LOG_DEBUG, "RES=%i, CMD_BUF: %s\nRULES LIST: %s", res, cmd_buf, cmd_out);
ndx = strstr(cmd_out, EXPIRE_COMMENT_PREFIX);
if(ndx == NULL)
{
/* we did not find an expected rule.
*/
log_msg(LOG_ERR,
"Did not find expire comment in rules list %i", i);
if (ch[i].active_rules > 0)
ch[i].active_rules--;
continue;
}
/* walk the list and process rules as needed.
*/
while (ndx != NULL) {
/* Jump forward and extract the timestamp
*/
ndx += strlen(EXPIRE_COMMENT_PREFIX);
/* remember this spot for when we look for the next
* rule.
*/
tmp_mark = ndx;
strlcpy(exp_str, ndx, sizeof(exp_str));
rule_exp = (time_t)atoll(exp_str);
if(rule_exp <= now)
{
/* Backtrack and get the rule number and delete it.
*/
rn_start = ndx;
while(--rn_start > cmd_out)
{
if(*rn_start == '\n')
break;
}
if(*rn_start != '\n')
{
/* This should not happen. But if it does, complain,
* decrement the active rule value, and go on.
*/
log_msg(LOG_ERR,
"Rule parse error while finding rule line start in chain %i", i);
if (ch[i].active_rules > 0)
ch[i].active_rules--;
break;
}
rn_start++;
rn_end = strchr(rn_start, ' ');
if(rn_end == NULL)
{
/* This should not happen. But if it does, complain,
* decrement the active rule value, and go on.
*/
log_msg(LOG_ERR,
"Rule parse error while finding rule number in chain %i", i);
if (ch[i].active_rules > 0)
ch[i].active_rules--;
break;
}
strlcpy(rule_num_str, rn_start, (rn_end - rn_start)+1);
rule_num = strtol_wrapper(rule_num_str, rn_offset, RCHK_MAX_IPT_RULE_NUM,
NO_EXIT_UPON_ERR, &is_err);
if(is_err != FKO_SUCCESS)
{
log_msg(LOG_ERR,
"Rule parse error while finding rule number in chain %i", i);
if (ch[i].active_rules > 0)
ch[i].active_rules--;
break;
}
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_DEL_RULE_ARGS,
opts->fw_config->fw_command,
ch[i].table,
ch[i].to_chain,
rule_num - rn_offset
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "check_firewall_rules() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Removed rule %s from %s with expire time of %u",
rule_num_str, ch[i].to_chain, rule_exp
);
rn_offset++;
if (ch[i].active_rules > 0)
ch[i].active_rules--;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
else
{
/* Track the minimum future rule expire time.
*/
if(rule_exp > now)
min_exp = (min_exp < rule_exp) ? min_exp : rule_exp;
}
/* Push our tracking index forward beyond (just processed) _exp_
* string so we can continue to the next rule in the list.
*/
ndx = strstr(tmp_mark, EXPIRE_COMMENT_PREFIX);
}
/* Set the next pending expire time accordingly. 0 if there are no
* more rules, or whatever the next expected (min_exp) time will be.
*/
if(ch[i].active_rules < 1)
ch[i].next_expire = 0;
else if(min_exp)
ch[i].next_expire = min_exp;
}
}
static void
ipt_chk_support(const fko_srv_options_t * const opts)
{
int res = 1;
struct fw_chain *in_chain = &(opts->fw_config->chain[IPT_INPUT_ACCESS]);
zero_cmd_buffers();
/* Add a harmless rule to the iptables INPUT chain and see if iptables
* supports '-C' to check for it. Set "have_ipt_chk_support" accordingly,
* delete the rule, and return.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_TMP_CHK_RULE_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->from_chain,
1, /* first rule */
in_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "ipt_chk_support() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
zero_cmd_buffers();
/* Now see if '-C' works - any output indicates failure
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_TMP_VERIFY_CHK_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->from_chain,
in_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "ipt_chk_support() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res) && strlen(err_buf))
{
log_msg(LOG_DEBUG, "ipt_chk_support() -C not supported");
have_ipt_chk_support = 0;
}
else
{
log_msg(LOG_DEBUG, "ipt_chk_support() -C supported");
have_ipt_chk_support = 1;
}
/* Delete the tmp rule
*/
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_DEL_RULE_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->from_chain,
1
);
run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
return;
}
static int
comment_match_exists(const fko_srv_options_t * const opts)
{
int res = 1;
char *ndx = NULL;
struct fw_chain *in_chain = &(opts->fw_config->chain[IPT_INPUT_ACCESS]);
zero_cmd_buffers();
/* Add a harmless rule to the iptables INPUT chain that uses the comment
* match and make sure it exists. If not, return zero. Otherwise, delete
* the rule and return true.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_TMP_COMMENT_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->from_chain,
1, /* first rule */
in_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "comment_match_exists() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_LIST_RULES_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->from_chain
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(cmd_out);
if(!EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
ndx = strstr(cmd_out, TMP_COMMENT);
if(ndx == NULL)
res = 0; /* did not find the tmp comment */
else
res = 1;
if(res == 1)
{
/* Delete the tmp comment rule
*/
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_DEL_RULE_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->from_chain,
1
);
run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
}
return res;
}
/* Iterate over the expired rule set and purge those that no longer have
* corresponding dynamic rules.
*/
void
ipfw_purge_expired_rules(const fko_srv_options_t *opts)
{
char *ndx, *co_end;
int i, res;
unsigned short curr_rule;
/* First, we get the current active dynamic rules for the expired rule
* set. Then we compare it to the expired rules in the rule_map. Any
* rules in the map that do not have a dynamic rule, can be deleted.
*/
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_SET_DYN_RULES_ARGS,
opts->fw_config->fw_command,
fwc.expire_set_num
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "ipfw_purge_expired_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
return;
}
/* We may not have any dynamic rules at all - someone might not have
* initiated a connection (for example)
*/
if (cmd_out[0] != '\0')
{
co_end = cmd_out + strlen(cmd_out);
if(opts->verbose > 1)
log_msg(LOG_INFO, "EXP RULES LIST: %s", cmd_out);
/* Find the "## Dynamic rules" string.
*/
ndx = strcasestr(cmd_out, "## Dynamic rules");
if(ndx == NULL)
{
log_msg(LOG_ERR,
"Unexpected error: did not find 'Dynamic rules' string in list output."
);
return;
}
/* Jump to the next newline char.
*/
ndx = strchr(ndx, '\n');
if(ndx == NULL)
{
log_msg(LOG_ERR,
"Unexpected error: did not find 'Dynamic rules' line terminating newline."
);
return;
}
/* Walk the list of dynamic rules (if any).
*/
while(ndx != NULL)
{
ndx++;
while(!isdigit(*ndx) && ndx < co_end)
ndx++;
if(ndx >= co_end)
break;
/* If we are at a digit, assume it is a rule number, extract it,
* and if it falls in the correct range, mark it (so it is not
* removed in the next step.
*/
if(isdigit(*ndx))
{
curr_rule = atoi(ndx);
if(curr_rule >= fwc.start_rule_num
&& curr_rule < fwc.start_rule_num + fwc.max_rules)
fwc.rule_map[curr_rule - fwc.start_rule_num] = RULE_TMP_MARKED;
}
ndx = strchr(ndx, '\n');
}
}
/* Now, walk the rule map and remove any still marked as expired.
*/
for(i=0; i<fwc.max_rules; i++)
{
/* If it is TMP_MARKED, set it back to EXPIRED and move on.
*/
if(fwc.rule_map[i] == RULE_TMP_MARKED)
{
fwc.rule_map[i] = RULE_EXPIRED;
continue;
}
/* If it is not expired, move on.
*/
if(fwc.rule_map[i] != RULE_EXPIRED)
continue;
/* This rule is ready to go away.
*/
zero_cmd_buffers();
curr_rule = fwc.start_rule_num + i;
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_DEL_RULE_ARGS,
opts->fw_config->fw_command,
#ifndef __APPLE__
fwc.expire_set_num,
#endif
curr_rule
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "ipfw_purge_expired_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
continue;
}
log_msg(LOG_INFO, "Purged rule %u from set %u", curr_rule, fwc.expire_set_num);
fwc.rule_map[curr_rule - fwc.start_rule_num] = RULE_FREE;
fwc.total_rules--;
}
}
/* Print all firewall rules currently instantiated by the running fwknopd
* daemon to stdout.
*/
int
fw_dump_rules(const fko_srv_options_t *opts)
{
int res, got_err = 0;
if (opts->fw_list_all)
{
fprintf(stdout, "Listing all ipfw rules...\n");
fflush(stdout);
zero_cmd_buffers();
/* Create the list command for all rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_ALL_RULES_ARGS,
opts->fw_config->fw_command
);
res = system(cmd_buf);
if (opts->verbose)
log_msg(LOG_INFO, "fw_dump_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
else
{
fprintf(stdout, "Listing fwknopd ipfw rules...\n");
fflush(stdout);
zero_cmd_buffers();
/* Create the list command for active rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->active_set_num
);
printf("\nActive Rules:\n");
res = system(cmd_buf);
if (opts->verbose)
log_msg(LOG_INFO, "fw_dump_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
/* Create the list command for expired rules
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPFW_LIST_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->expire_set_num
);
printf("\nExpired Rules:\n");
res = system(cmd_buf);
if (opts->verbose)
log_msg(LOG_INFO, "fw_dump_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
return(got_err);
}
/* Quietly flush and delete all fwknop custom chains.
*/
static void
delete_all_chains(const fko_srv_options_t *opts)
{
int i, res;
int jump_rule_num;
for(i=0; i<(NUM_FWKNOP_ACCESS_TYPES); i++)
{
if(fwc.chain[i].target[0] == '\0')
continue;
/* First look for a jump rule to this chain and remove it if it
* is there.
*/
if((jump_rule_num = jump_rule_exists(i)) > 0)
{
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_DEL_RULE_ARGS,
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].from_chain,
jump_rule_num
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "delete_all_chains() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
zero_cmd_buffers();
/* Now flush and remove the chain.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1,
"(%s " IPT_FLUSH_CHAIN_ARGS "; %s " IPT_DEL_CHAIN_ARGS ")", // > /dev/null 2>&1",
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].to_chain,
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "delete_all_chains() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
}
/* Iterate over the configure firewall access chains and purge expired
* firewall rules.
*/
void
check_firewall_rules(const fko_srv_options_t *opts)
{
char exp_str[12];
char anchor_rules_copy[STANDARD_CMD_OUT_BUFSIZE];
char write_cmd[CMD_BUFSIZE];
char *ndx, *tmp_mark, *tmp_ndx, *newline_tmp_ndx;
time_t now, rule_exp, min_exp=0;
int i=0, res=0, anchor_ndx=0, is_delete=0;
FILE *pfctl_fd = NULL;
/* If we have not yet reached our expected next expire
time, continue.
*/
if(fwc.next_expire == 0)
return;
time(&now);
if (fwc.next_expire > now)
return;
zero_cmd_buffers();
/* There should be a rule to delete. Get the current list of
* rules and delete the ones that are expired.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " PF_LIST_ANCHOR_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->anchor
);
res = run_extcmd(cmd_buf, cmd_out, STANDARD_CMD_OUT_BUFSIZE, 0);
if(!EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, cmd_out);
return;
}
/* Find the first _exp_ string (if any).
*/
ndx = strstr(cmd_out, EXPIRE_COMMENT_PREFIX);
if(ndx == NULL)
{
/* we did not find an expected rule.
*/
log_msg(LOG_ERR,
"Did not find expire comment in rules list %i.\n", i);
return;
}
memset(anchor_rules_copy, 0x0, STANDARD_CMD_OUT_BUFSIZE);
/* Walk the list and process rules as needed.
*/
while (ndx != NULL)
{
/* Jump forward and extract the timestamp
*/
ndx += strlen(EXPIRE_COMMENT_PREFIX);
/* remember this spot for when we look for the next
* rule.
*/
tmp_mark = ndx;
strlcpy(exp_str, ndx, 11);
rule_exp = (time_t)atoll(exp_str);
if(rule_exp <= now)
{
/* We are going to delete this rule, and because we rebuild the
* PF anchor to include all rules that haven't expired, to delete
* this rule we just skip to the next one.
*/
log_msg(LOG_INFO, "Deleting rule with expire time of %u.", rule_exp);
if (fwc.active_rules > 0)
fwc.active_rules--;
is_delete = 1;
}
else
{
/* The rule has not expired, so copy it into the anchor string that
* lists current rules and will be used to feed
* 'pfctl -a <anchor> -f -'.
*/
/* back up to the previous newline or the beginning of the rules
* output string.
*/
tmp_ndx = ndx;
while(--tmp_ndx > cmd_out)
{
if(*tmp_ndx == '\n')
break;
}
if(*tmp_ndx == '\n')
{
tmp_ndx++;
}
/* may sure the rule begins with the string "pass", and make sure
* it ends with a newline. Bail if either test fails.
*/
if (strlen(tmp_ndx) <= strlen("pass")
|| strncmp(tmp_ndx, "pass", strlen("pass")) != 0)
{
break;
}
newline_tmp_ndx = tmp_ndx;
while (*newline_tmp_ndx != '\n' && *newline_tmp_ndx != '\0')
{
newline_tmp_ndx++;
}
if (*newline_tmp_ndx != '\n')
break;
/* copy the whole rule to the next newline (includes the expiration
time).
*/
while (*tmp_ndx != '\n' && *tmp_ndx != '\0'
&& anchor_ndx < STANDARD_CMD_OUT_BUFSIZE)
{
anchor_rules_copy[anchor_ndx] = *tmp_ndx;
tmp_ndx++;
anchor_ndx++;
}
anchor_rules_copy[anchor_ndx] = '\n';
anchor_ndx++;
/* Track the minimum future rule expire time.
*/
if(rule_exp > now)
min_exp = (min_exp < rule_exp) ? min_exp : rule_exp;
}
/* Push our tracking index forward beyond (just processed) _exp_
* string so we can continue to the next rule in the list.
*/
ndx = strstr(tmp_mark, EXPIRE_COMMENT_PREFIX);
}
if (is_delete)
{
/* We re-instantiate the anchor rules with the new rules string that
* has the rule(s) deleted. If there isn't at least one "pass" rule,
* then we just flush the anchor.
*/
if (strlen(anchor_rules_copy) > strlen("pass")
&& strncmp(anchor_rules_copy, "pass", strlen("pass")) == 0)
{
memset(write_cmd, 0x0, CMD_BUFSIZE);
snprintf(write_cmd, CMD_BUFSIZE-1, "%s " PF_WRITE_ANCHOR_RULES_ARGS,
opts->fw_config->fw_command,
opts->fw_config->anchor
);
if ((pfctl_fd = popen(write_cmd, "w")) == NULL)
{
log_msg(LOG_WARNING, "Could not execute command: %s",
write_cmd);
return;
}
if (fwrite(anchor_rules_copy, strlen(anchor_rules_copy), 1, pfctl_fd) != 1)
{
log_msg(LOG_WARNING, "Could not write rules to pf anchor");
}
pclose(pfctl_fd);
}
else
{
delete_all_anchor_rules(opts);
}
}
/* Set the next pending expire time accordingly. 0 if there are no
* more rules, or whatever the next expected (min_exp) time will be.
*/
if(fwc.active_rules < 1)
fwc.next_expire = 0;
else if(min_exp)
fwc.next_expire = min_exp;
return;
}
/* Quietly flush and delete all fwknop custom chains.
*/
static void
delete_all_chains(const fko_srv_options_t * const opts)
{
int i, res, cmd_ctr = 0;
for(i=0; i < NUM_FWKNOP_ACCESS_TYPES; i++)
{
if(fwc.chain[i].target[0] == '\0')
continue;
/* First look for a jump rule to this chain and remove it if it
* is there.
*/
cmd_ctr = 0;
while(cmd_ctr < CMD_LOOP_TRIES && (jump_rule_exists(opts, i) == 1))
{
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_DEL_JUMP_RULE_ARGS,
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].from_chain,
fwc.chain[i].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE,
WANT_STDERR, NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "delete_all_chains() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
cmd_ctr++;
}
zero_cmd_buffers();
/* Now flush and remove the chain.
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_FLUSH_CHAIN_ARGS,
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, WANT_STDERR,
NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "delete_all_chains() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_DEL_CHAIN_ARGS,
fwc.fw_command,
fwc.chain[i].table,
fwc.chain[i].to_chain
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, WANT_STDERR,
NO_TIMEOUT, &pid_status, opts);
chop_newline(err_buf);
log_msg(LOG_DEBUG, "delete_all_chains() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
return;
}
/* Print all firewall rules currently instantiated by the running fwknopd
* daemon to stdout.
*/
int
fw_dump_rules(const fko_srv_options_t * const opts)
{
int i, res, got_err = 0;
struct fw_chain *ch = opts->fw_config->chain;
if (opts->fw_list_all == 1)
{
fprintf(stdout, "Listing all iptables rules in applicable tables...\n");
fflush(stdout);
for(i=0; i < NUM_FWKNOP_ACCESS_TYPES; i++)
{
if(fwc.chain[i].target[0] == '\0')
continue;
zero_cmd_buffers();
/* Create the list command
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_LIST_ALL_RULES_ARGS,
opts->fw_config->fw_command,
ch[i].table
);
res = run_extcmd(cmd_buf, NULL, 0, NO_STDERR,
NO_TIMEOUT, &pid_status, opts);
log_msg(LOG_DEBUG, "fw_dump_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
}
else
{
fprintf(stdout, "Listing rules in fwknopd iptables chains...\n");
fflush(stdout);
for(i=0; i < NUM_FWKNOP_ACCESS_TYPES; i++)
{
if(fwc.chain[i].target[0] == '\0')
continue;
zero_cmd_buffers();
/* Create the list command
*/
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_LIST_RULES_ARGS,
opts->fw_config->fw_command,
ch[i].table,
ch[i].to_chain
);
fprintf(stdout, "\n");
fflush(stdout);
res = run_extcmd(cmd_buf, NULL, 0, NO_STDERR,
NO_TIMEOUT, &pid_status, opts);
log_msg(LOG_DEBUG, "fw_dump_rules() CMD: '%s' (res: %d)",
cmd_buf, res);
/* Expect full success on this */
if(! EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
got_err++;
}
}
}
return(got_err);
}
/* Rule Processing - Create an access request...
*/
int
process_spa_request(const fko_srv_options_t *opts, const acc_stanza_t *acc, spa_data_t *spadat)
{
char nat_ip[MAX_IPV4_STR_LEN] = {0};
char snat_target[SNAT_TARGET_BUFSIZE] = {0};
char *ndx;
unsigned int nat_port = 0;
acc_port_list_t *port_list = NULL;
acc_port_list_t *ple;
unsigned int fst_proto;
unsigned int fst_port;
struct fw_chain *in_chain = &(opts->fw_config->chain[IPT_INPUT_ACCESS]);
struct fw_chain *out_chain = &(opts->fw_config->chain[IPT_OUTPUT_ACCESS]);
struct fw_chain *fwd_chain = &(opts->fw_config->chain[IPT_FORWARD_ACCESS]);
struct fw_chain *dnat_chain = &(opts->fw_config->chain[IPT_DNAT_ACCESS]);
struct fw_chain *snat_chain; /* We assign this later (if we need to). */
int res = 0;
time_t now;
unsigned int exp_ts;
/* Parse and expand our access message.
*/
if(expand_acc_port_list(&port_list, spadat->spa_message_remain) != 1)
return res;
/* Start at the top of the proto-port list...
*/
ple = port_list;
/* Remember the first proto/port combo in case we need them
* for NAT access requests.
*/
fst_proto = ple->proto;
fst_port = ple->port;
/* Set our expire time value.
*/
time(&now);
exp_ts = now + spadat->fw_access_timeout;
/* For straight access requests, we currently support multiple proto/port
* request.
*/
if((spadat->message_type == FKO_ACCESS_MSG
|| spadat->message_type == FKO_CLIENT_TIMEOUT_ACCESS_MSG) && !acc->force_nat)
{
/* Check to make sure that the jump rules exist for each
* required chain
*/
if(jump_rule_exists(IPT_INPUT_ACCESS) == 0)
add_jump_rule(opts, IPT_INPUT_ACCESS);
if(out_chain->to_chain != NULL && strlen(out_chain->to_chain))
if(jump_rule_exists(IPT_OUTPUT_ACCESS) == 0)
add_jump_rule(opts, IPT_OUTPUT_ACCESS);
/* Create an access command for each proto/port for the source ip.
*/
while(ple != NULL)
{
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_RULE_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->to_chain,
ple->proto,
spadat->use_src_ip,
ple->port,
exp_ts,
in_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added Rule to %s for %s, %s expires at %u",
in_chain->to_chain, spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
in_chain->active_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(in_chain->next_expire < now || exp_ts < in_chain->next_expire)
in_chain->next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
/* If we have to make an corresponding OUTPUT rule if out_chain target
* is not NULL.
*/
if(out_chain->to_chain != NULL && strlen(out_chain->to_chain))
{
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_OUT_RULE_ARGS,
opts->fw_config->fw_command,
out_chain->table,
out_chain->to_chain,
ple->proto,
spadat->use_src_ip,
ple->port,
exp_ts,
out_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added OUTPUT Rule to %s for %s, %s expires at %u",
out_chain->to_chain, spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
out_chain->active_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(out_chain->next_expire < now || exp_ts < out_chain->next_expire)
out_chain->next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
ple = ple->next;
}
}
/* NAT requests... */
else if(spadat->message_type == FKO_LOCAL_NAT_ACCESS_MSG
|| spadat->message_type == FKO_CLIENT_TIMEOUT_LOCAL_NAT_ACCESS_MSG
|| spadat->message_type == FKO_NAT_ACCESS_MSG
|| spadat->message_type == FKO_CLIENT_TIMEOUT_NAT_ACCESS_MSG
|| acc->force_nat)
{
/* Parse out the NAT IP and Port components.
*/
if(acc->force_nat)
{
strlcpy(nat_ip, acc->force_nat_ip, MAX_IPV4_STR_LEN);
nat_port = acc->force_nat_port;
}
else
{
ndx = strchr(spadat->nat_access, ',');
if(ndx != NULL)
{
strlcpy(nat_ip, spadat->nat_access, (ndx-spadat->nat_access)+1);
nat_port = atoi(ndx+1);
}
}
if(spadat->message_type == FKO_LOCAL_NAT_ACCESS_MSG)
{
/* Need to add an ACCEPT rule into the INPUT chain
*/
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_RULE_ARGS,
opts->fw_config->fw_command,
in_chain->table,
in_chain->to_chain,
fst_proto,
spadat->use_src_ip,
nat_port,
exp_ts,
in_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added Rule to %s for %s, %s expires at %u",
in_chain->to_chain, spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
in_chain->active_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(in_chain->next_expire < now || exp_ts < in_chain->next_expire)
in_chain->next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
else if(fwd_chain->to_chain != NULL && strlen(fwd_chain->to_chain))
{
/* Make our FORWARD and NAT rules, and make sure the
* required jump rule exists
*/
if (jump_rule_exists(IPT_FORWARD_ACCESS) == 0)
add_jump_rule(opts, IPT_FORWARD_ACCESS);
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_FWD_RULE_ARGS,
opts->fw_config->fw_command,
fwd_chain->table,
fwd_chain->to_chain,
fst_proto,
spadat->use_src_ip,
nat_ip,
nat_port,
exp_ts,
fwd_chain->target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added FORWARD Rule to %s for %s, %s expires at %u",
fwd_chain->to_chain, spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
fwd_chain->active_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(fwd_chain->next_expire < now || exp_ts < fwd_chain->next_expire)
fwd_chain->next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
if(dnat_chain->to_chain != NULL && strlen(dnat_chain->to_chain))
{
/* Make sure the required jump rule exists
*/
if (jump_rule_exists(IPT_DNAT_ACCESS) == 0)
add_jump_rule(opts, IPT_DNAT_ACCESS);
zero_cmd_buffers();
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_DNAT_RULE_ARGS,
opts->fw_config->fw_command,
dnat_chain->table,
dnat_chain->to_chain,
fst_proto,
spadat->use_src_ip,
fst_port,
exp_ts,
dnat_chain->target,
nat_ip,
nat_port
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added DNAT Rule to %s for %s, %s expires at %u",
dnat_chain->to_chain, spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
dnat_chain->active_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(dnat_chain->next_expire < now || exp_ts < dnat_chain->next_expire)
dnat_chain->next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
/* If SNAT (or MASQUERADE) is wanted, then we add those rules here as well.
*/
if(strncasecmp(opts->config[CONF_ENABLE_IPT_SNAT], "Y", 1) == 0)
{
zero_cmd_buffers();
/* Setup some parameter depending on whether we are using SNAT
* or MASQUERADE.
*/
if(strncasecmp(opts->config[CONF_SNAT_TRANSLATE_IP], "__CHANGEME__", 10)!=0)
{
/* Using static SNAT */
snat_chain = &(opts->fw_config->chain[IPT_SNAT_ACCESS]);
snprintf(snat_target, SNAT_TARGET_BUFSIZE-1,
"--to-source %s:%i", opts->config[CONF_SNAT_TRANSLATE_IP],
fst_port);
}
else
{
/* Using MASQUERADE */
snat_chain = &(opts->fw_config->chain[IPT_MASQUERADE_ACCESS]);
snprintf(snat_target, SNAT_TARGET_BUFSIZE-1,
"--to-ports %i", fst_port);
}
snprintf(cmd_buf, CMD_BUFSIZE-1, "%s " IPT_ADD_SNAT_RULE_ARGS,
opts->fw_config->fw_command,
snat_chain->table,
snat_chain->to_chain,
fst_proto,
nat_ip,
nat_port,
exp_ts,
snat_chain->target,
snat_target
);
res = run_extcmd(cmd_buf, err_buf, CMD_BUFSIZE, 0);
if (opts->verbose)
log_msg(LOG_INFO, "process_spa_request() CMD: '%s' (res: %d, err: %s)",
cmd_buf, res, err_buf);
if(EXTCMD_IS_SUCCESS(res))
{
log_msg(LOG_INFO, "Added Source NAT Rule to %s for %s, %s expires at %u",
snat_chain->to_chain, spadat->use_src_ip,
spadat->spa_message_remain, exp_ts
);
snat_chain->active_rules++;
/* Reset the next expected expire time for this chain if it
* is warranted.
*/
if(snat_chain->next_expire < now || exp_ts < snat_chain->next_expire)
snat_chain->next_expire = exp_ts;
}
else
log_msg(LOG_ERR, "Error %i from cmd:'%s': %s", res, cmd_buf, err_buf);
}
}
/* Done with the port list for access rules.
*/
free_acc_port_list(port_list);
return(res);
}
