freebsd-dev/sbin/dhclient/clparse.c
Brooks Davis 8794fdbb48 Add __FBSDID to all .c files in dhclient to aid in determining file
versions when dealing with user problems.
2005-08-23 23:59:55 +00:00

942 lines
23 KiB
C

/* $OpenBSD: clparse.c,v 1.18 2004/09/15 18:15:18 henning Exp $ */
/* Parser for dhclient config and lease files... */
/*
* Copyright (c) 1997 The Internet Software Consortium.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of The Internet Software Consortium 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 BY THE INTERNET SOFTWARE CONSORTIUM AND
* CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "dhcpd.h"
#include "dhctoken.h"
struct client_config top_level_config;
struct interface_info *dummy_interfaces;
extern struct interface_info *ifi;
char client_script_name[] = "/sbin/dhclient-script";
/*
* client-conf-file :== client-declarations EOF
* client-declarations :== <nil>
* | client-declaration
* | client-declarations client-declaration
*/
int
read_client_conf(void)
{
FILE *cfile;
char *val;
int token;
struct client_config *config;
new_parse(path_dhclient_conf);
/* Set up the initial dhcp option universe. */
initialize_universes();
/* Initialize the top level client configuration. */
memset(&top_level_config, 0, sizeof(top_level_config));
/* Set some defaults... */
top_level_config.timeout = 60;
top_level_config.select_interval = 0;
top_level_config.reboot_timeout = 10;
top_level_config.retry_interval = 300;
top_level_config.backoff_cutoff = 15;
top_level_config.initial_interval = 3;
top_level_config.bootp_policy = ACCEPT;
top_level_config.script_name = client_script_name;
top_level_config.requested_options
[top_level_config.requested_option_count++] = DHO_SUBNET_MASK;
top_level_config.requested_options
[top_level_config.requested_option_count++] = DHO_BROADCAST_ADDRESS;
top_level_config.requested_options
[top_level_config.requested_option_count++] = DHO_TIME_OFFSET;
top_level_config.requested_options
[top_level_config.requested_option_count++] = DHO_ROUTERS;
top_level_config.requested_options
[top_level_config.requested_option_count++] = DHO_DOMAIN_NAME;
top_level_config.requested_options
[top_level_config.requested_option_count++] =
DHO_DOMAIN_NAME_SERVERS;
top_level_config.requested_options
[top_level_config.requested_option_count++] = DHO_HOST_NAME;
if ((cfile = fopen(path_dhclient_conf, "r")) != NULL) {
do {
token = peek_token(&val, cfile);
if (token == EOF)
break;
parse_client_statement(cfile, NULL, &top_level_config);
} while (1);
token = next_token(&val, cfile); /* Clear the peek buffer */
fclose(cfile);
}
/*
* Set up state and config structures for clients that don't
* have per-interface configuration declarations.
*/
config = NULL;
if (!ifi->client) {
ifi->client = malloc(sizeof(struct client_state));
if (!ifi->client)
error("no memory for client state.");
memset(ifi->client, 0, sizeof(*(ifi->client)));
}
if (!ifi->client->config) {
if (!config) {
config = malloc(sizeof(struct client_config));
if (!config)
error("no memory for client config.");
memcpy(config, &top_level_config,
sizeof(top_level_config));
}
ifi->client->config = config;
}
return (!warnings_occurred);
}
/*
* lease-file :== client-lease-statements EOF
* client-lease-statements :== <nil>
* | client-lease-statements LEASE client-lease-statement
*/
void
read_client_leases(void)
{
FILE *cfile;
char *val;
int token;
new_parse(path_dhclient_db);
/* Open the lease file. If we can't open it, just return -
we can safely trust the server to remember our state. */
if ((cfile = fopen(path_dhclient_db, "r")) == NULL)
return;
do {
token = next_token(&val, cfile);
if (token == EOF)
break;
if (token != LEASE) {
warning("Corrupt lease file - possible data loss!");
skip_to_semi(cfile);
break;
} else
parse_client_lease_statement(cfile, 0);
} while (1);
fclose(cfile);
}
/*
* client-declaration :==
* SEND option-decl |
* DEFAULT option-decl |
* SUPERSEDE option-decl |
* PREPEND option-decl |
* APPEND option-decl |
* hardware-declaration |
* REQUEST option-list |
* REQUIRE option-list |
* TIMEOUT number |
* RETRY number |
* REBOOT number |
* SELECT_TIMEOUT number |
* SCRIPT string |
* interface-declaration |
* LEASE client-lease-statement |
* ALIAS client-lease-statement
*/
void
parse_client_statement(FILE *cfile, struct interface_info *ip,
struct client_config *config)
{
int token;
char *val;
struct option *option;
switch (next_token(&val, cfile)) {
case SEND:
parse_option_decl(cfile, &config->send_options[0]);
return;
case DEFAULT:
option = parse_option_decl(cfile, &config->defaults[0]);
if (option)
config->default_actions[option->code] = ACTION_DEFAULT;
return;
case SUPERSEDE:
option = parse_option_decl(cfile, &config->defaults[0]);
if (option)
config->default_actions[option->code] =
ACTION_SUPERSEDE;
return;
case APPEND:
option = parse_option_decl(cfile, &config->defaults[0]);
if (option)
config->default_actions[option->code] = ACTION_APPEND;
return;
case PREPEND:
option = parse_option_decl(cfile, &config->defaults[0]);
if (option)
config->default_actions[option->code] = ACTION_PREPEND;
return;
case MEDIA:
parse_string_list(cfile, &config->media, 1);
return;
case HARDWARE:
if (ip)
parse_hardware_param(cfile, &ip->hw_address);
else {
parse_warn("hardware address parameter %s",
"not allowed here.");
skip_to_semi(cfile);
}
return;
case REQUEST:
config->requested_option_count =
parse_option_list(cfile, config->requested_options);
return;
case REQUIRE:
memset(config->required_options, 0,
sizeof(config->required_options));
parse_option_list(cfile, config->required_options);
return;
case TIMEOUT:
parse_lease_time(cfile, &config->timeout);
return;
case RETRY:
parse_lease_time(cfile, &config->retry_interval);
return;
case SELECT_TIMEOUT:
parse_lease_time(cfile, &config->select_interval);
return;
case REBOOT:
parse_lease_time(cfile, &config->reboot_timeout);
return;
case BACKOFF_CUTOFF:
parse_lease_time(cfile, &config->backoff_cutoff);
return;
case INITIAL_INTERVAL:
parse_lease_time(cfile, &config->initial_interval);
return;
case SCRIPT:
config->script_name = parse_string(cfile);
return;
case INTERFACE:
if (ip)
parse_warn("nested interface declaration.");
parse_interface_declaration(cfile, config);
return;
case LEASE:
parse_client_lease_statement(cfile, 1);
return;
case ALIAS:
parse_client_lease_statement(cfile, 2);
return;
case REJECT:
parse_reject_statement(cfile, config);
return;
default:
parse_warn("expecting a statement.");
skip_to_semi(cfile);
break;
}
token = next_token(&val, cfile);
if (token != SEMI) {
parse_warn("semicolon expected.");
skip_to_semi(cfile);
}
}
int
parse_X(FILE *cfile, u_int8_t *buf, int max)
{
int token;
char *val;
int len;
token = peek_token(&val, cfile);
if (token == NUMBER_OR_NAME || token == NUMBER) {
len = 0;
do {
token = next_token(&val, cfile);
if (token != NUMBER && token != NUMBER_OR_NAME) {
parse_warn("expecting hexadecimal constant.");
skip_to_semi(cfile);
return (0);
}
convert_num(&buf[len], val, 16, 8);
if (len++ > max) {
parse_warn("hexadecimal constant too long.");
skip_to_semi(cfile);
return (0);
}
token = peek_token(&val, cfile);
if (token == COLON)
token = next_token(&val, cfile);
} while (token == COLON);
val = (char *)buf;
} else if (token == STRING) {
token = next_token(&val, cfile);
len = strlen(val);
if (len + 1 > max) {
parse_warn("string constant too long.");
skip_to_semi(cfile);
return (0);
}
memcpy(buf, val, len + 1);
} else {
parse_warn("expecting string or hexadecimal data");
skip_to_semi(cfile);
return (0);
}
return (len);
}
/*
* option-list :== option_name |
* option_list COMMA option_name
*/
int
parse_option_list(FILE *cfile, u_int8_t *list)
{
int ix, i;
int token;
char *val;
ix = 0;
do {
token = next_token(&val, cfile);
if (!is_identifier(token)) {
parse_warn("expected option name.");
skip_to_semi(cfile);
return (0);
}
for (i = 0; i < 256; i++)
if (!strcasecmp(dhcp_options[i].name, val))
break;
if (i == 256) {
parse_warn("%s: unexpected option name.", val);
skip_to_semi(cfile);
return (0);
}
list[ix++] = i;
if (ix == 256) {
parse_warn("%s: too many options.", val);
skip_to_semi(cfile);
return (0);
}
token = next_token(&val, cfile);
} while (token == COMMA);
if (token != SEMI) {
parse_warn("expecting semicolon.");
skip_to_semi(cfile);
return (0);
}
return (ix);
}
/*
* interface-declaration :==
* INTERFACE string LBRACE client-declarations RBRACE
*/
void
parse_interface_declaration(FILE *cfile, struct client_config *outer_config)
{
int token;
char *val;
struct interface_info *ip;
token = next_token(&val, cfile);
if (token != STRING) {
parse_warn("expecting interface name (in quotes).");
skip_to_semi(cfile);
return;
}
ip = interface_or_dummy(val);
if (!ip->client)
make_client_state(ip);
if (!ip->client->config)
make_client_config(ip, outer_config);
token = next_token(&val, cfile);
if (token != LBRACE) {
parse_warn("expecting left brace.");
skip_to_semi(cfile);
return;
}
do {
token = peek_token(&val, cfile);
if (token == EOF) {
parse_warn("unterminated interface declaration.");
return;
}
if (token == RBRACE)
break;
parse_client_statement(cfile, ip, ip->client->config);
} while (1);
token = next_token(&val, cfile);
}
struct interface_info *
interface_or_dummy(char *name)
{
struct interface_info *ip;
/* Find the interface (if any) that matches the name. */
if (!strcmp(ifi->name, name))
return (ifi);
/* If it's not a real interface, see if it's on the dummy list. */
for (ip = dummy_interfaces; ip; ip = ip->next)
if (!strcmp(ip->name, name))
return (ip);
/*
* If we didn't find an interface, make a dummy interface as a
* placeholder.
*/
ip = malloc(sizeof(*ip));
if (!ip)
error("Insufficient memory to record interface %s", name);
memset(ip, 0, sizeof(*ip));
strlcpy(ip->name, name, IFNAMSIZ);
ip->next = dummy_interfaces;
dummy_interfaces = ip;
return (ip);
}
void
make_client_state(struct interface_info *ip)
{
ip->client = malloc(sizeof(*(ip->client)));
if (!ip->client)
error("no memory for state on %s", ip->name);
memset(ip->client, 0, sizeof(*(ip->client)));
}
void
make_client_config(struct interface_info *ip, struct client_config *config)
{
ip->client->config = malloc(sizeof(struct client_config));
if (!ip->client->config)
error("no memory for config for %s", ip->name);
memset(ip->client->config, 0, sizeof(*(ip->client->config)));
memcpy(ip->client->config, config, sizeof(*config));
}
/*
* client-lease-statement :==
* RBRACE client-lease-declarations LBRACE
*
* client-lease-declarations :==
* <nil> |
* client-lease-declaration |
* client-lease-declarations client-lease-declaration
*/
void
parse_client_lease_statement(FILE *cfile, int is_static)
{
struct client_lease *lease, *lp, *pl;
struct interface_info *ip;
int token;
char *val;
token = next_token(&val, cfile);
if (token != LBRACE) {
parse_warn("expecting left brace.");
skip_to_semi(cfile);
return;
}
lease = malloc(sizeof(struct client_lease));
if (!lease)
error("no memory for lease.");
memset(lease, 0, sizeof(*lease));
lease->is_static = is_static;
ip = NULL;
do {
token = peek_token(&val, cfile);
if (token == EOF) {
parse_warn("unterminated lease declaration.");
return;
}
if (token == RBRACE)
break;
parse_client_lease_declaration(cfile, lease, &ip);
} while (1);
token = next_token(&val, cfile);
/* If the lease declaration didn't include an interface
* declaration that we recognized, it's of no use to us.
*/
if (!ip) {
free_client_lease(lease);
return;
}
/* Make sure there's a client state structure... */
if (!ip->client)
make_client_state(ip);
/* If this is an alias lease, it doesn't need to be sorted in. */
if (is_static == 2) {
ip->client->alias = lease;
return;
}
/*
* The new lease may supersede a lease that's not the active
* lease but is still on the lease list, so scan the lease list
* looking for a lease with the same address, and if we find it,
* toss it.
*/
pl = NULL;
for (lp = ip->client->leases; lp; lp = lp->next) {
if (lp->address.len == lease->address.len &&
!memcmp(lp->address.iabuf, lease->address.iabuf,
lease->address.len)) {
if (pl)
pl->next = lp->next;
else
ip->client->leases = lp->next;
free_client_lease(lp);
break;
}
}
/*
* If this is a preloaded lease, just put it on the list of
* recorded leases - don't make it the active lease.
*/
if (is_static) {
lease->next = ip->client->leases;
ip->client->leases = lease;
return;
}
/*
* The last lease in the lease file on a particular interface is
* the active lease for that interface. Of course, we don't
* know what the last lease in the file is until we've parsed
* the whole file, so at this point, we assume that the lease we
* just parsed is the active lease for its interface. If
* there's already an active lease for the interface, and this
* lease is for the same ip address, then we just toss the old
* active lease and replace it with this one. If this lease is
* for a different address, then if the old active lease has
* expired, we dump it; if not, we put it on the list of leases
* for this interface which are still valid but no longer
* active.
*/
if (ip->client->active) {
if (ip->client->active->expiry < cur_time)
free_client_lease(ip->client->active);
else if (ip->client->active->address.len ==
lease->address.len &&
!memcmp(ip->client->active->address.iabuf,
lease->address.iabuf, lease->address.len))
free_client_lease(ip->client->active);
else {
ip->client->active->next = ip->client->leases;
ip->client->leases = ip->client->active;
}
}
ip->client->active = lease;
/* Phew. */
}
/*
* client-lease-declaration :==
* BOOTP |
* INTERFACE string |
* FIXED_ADDR ip_address |
* FILENAME string |
* SERVER_NAME string |
* OPTION option-decl |
* RENEW time-decl |
* REBIND time-decl |
* EXPIRE time-decl
*/
void
parse_client_lease_declaration(FILE *cfile, struct client_lease *lease,
struct interface_info **ipp)
{
int token;
char *val;
struct interface_info *ip;
switch (next_token(&val, cfile)) {
case BOOTP:
lease->is_bootp = 1;
break;
case INTERFACE:
token = next_token(&val, cfile);
if (token != STRING) {
parse_warn("expecting interface name (in quotes).");
skip_to_semi(cfile);
break;
}
ip = interface_or_dummy(val);
*ipp = ip;
break;
case FIXED_ADDR:
if (!parse_ip_addr(cfile, &lease->address))
return;
break;
case MEDIUM:
parse_string_list(cfile, &lease->medium, 0);
return;
case FILENAME:
lease->filename = parse_string(cfile);
return;
case SERVER_NAME:
lease->server_name = parse_string(cfile);
return;
case RENEW:
lease->renewal = parse_date(cfile);
return;
case REBIND:
lease->rebind = parse_date(cfile);
return;
case EXPIRE:
lease->expiry = parse_date(cfile);
return;
case OPTION:
parse_option_decl(cfile, lease->options);
return;
default:
parse_warn("expecting lease declaration.");
skip_to_semi(cfile);
break;
}
token = next_token(&val, cfile);
if (token != SEMI) {
parse_warn("expecting semicolon.");
skip_to_semi(cfile);
}
}
struct option *
parse_option_decl(FILE *cfile, struct option_data *options)
{
char *val;
int token;
u_int8_t buf[4];
u_int8_t hunkbuf[1024];
int hunkix = 0;
char *vendor;
char *fmt;
struct universe *universe;
struct option *option;
struct iaddr ip_addr;
u_int8_t *dp;
int len;
int nul_term = 0;
token = next_token(&val, cfile);
if (!is_identifier(token)) {
parse_warn("expecting identifier after option keyword.");
if (token != SEMI)
skip_to_semi(cfile);
return (NULL);
}
if ((vendor = strdup(val)) == NULL)
error("no memory for vendor information.");
token = peek_token(&val, cfile);
if (token == DOT) {
/* Go ahead and take the DOT token... */
token = next_token(&val, cfile);
/* The next token should be an identifier... */
token = next_token(&val, cfile);
if (!is_identifier(token)) {
parse_warn("expecting identifier after '.'");
if (token != SEMI)
skip_to_semi(cfile);
return (NULL);
}
/* Look up the option name hash table for the specified
vendor. */
universe = ((struct universe *)hash_lookup(&universe_hash,
(unsigned char *)vendor, 0));
/* If it's not there, we can't parse the rest of the
declaration. */
if (!universe) {
parse_warn("no vendor named %s.", vendor);
skip_to_semi(cfile);
return (NULL);
}
} else {
/* Use the default hash table, which contains all the
standard dhcp option names. */
val = vendor;
universe = &dhcp_universe;
}
/* Look up the actual option info... */
option = (struct option *)hash_lookup(universe->hash,
(unsigned char *)val, 0);
/* If we didn't get an option structure, it's an undefined option. */
if (!option) {
if (val == vendor)
parse_warn("no option named %s", val);
else
parse_warn("no option named %s for vendor %s",
val, vendor);
skip_to_semi(cfile);
return (NULL);
}
/* Free the initial identifier token. */
free(vendor);
/* Parse the option data... */
do {
for (fmt = option->format; *fmt; fmt++) {
if (*fmt == 'A')
break;
switch (*fmt) {
case 'X':
len = parse_X(cfile, &hunkbuf[hunkix],
sizeof(hunkbuf) - hunkix);
hunkix += len;
break;
case 't': /* Text string... */
token = next_token(&val, cfile);
if (token != STRING) {
parse_warn("expecting string.");
skip_to_semi(cfile);
return (NULL);
}
len = strlen(val);
if (hunkix + len + 1 > sizeof(hunkbuf)) {
parse_warn("option data buffer %s",
"overflow");
skip_to_semi(cfile);
return (NULL);
}
memcpy(&hunkbuf[hunkix], val, len + 1);
nul_term = 1;
hunkix += len;
break;
case 'I': /* IP address. */
if (!parse_ip_addr(cfile, &ip_addr))
return (NULL);
len = ip_addr.len;
dp = ip_addr.iabuf;
alloc:
if (hunkix + len > sizeof(hunkbuf)) {
parse_warn("option data buffer "
"overflow");
skip_to_semi(cfile);
return (NULL);
}
memcpy(&hunkbuf[hunkix], dp, len);
hunkix += len;
break;
case 'L': /* Unsigned 32-bit integer... */
case 'l': /* Signed 32-bit integer... */
token = next_token(&val, cfile);
if (token != NUMBER) {
need_number:
parse_warn("expecting number.");
if (token != SEMI)
skip_to_semi(cfile);
return (NULL);
}
convert_num(buf, val, 0, 32);
len = 4;
dp = buf;
goto alloc;
case 's': /* Signed 16-bit integer. */
case 'S': /* Unsigned 16-bit integer. */
token = next_token(&val, cfile);
if (token != NUMBER)
goto need_number;
convert_num(buf, val, 0, 16);
len = 2;
dp = buf;
goto alloc;
case 'b': /* Signed 8-bit integer. */
case 'B': /* Unsigned 8-bit integer. */
token = next_token(&val, cfile);
if (token != NUMBER)
goto need_number;
convert_num(buf, val, 0, 8);
len = 1;
dp = buf;
goto alloc;
case 'f': /* Boolean flag. */
token = next_token(&val, cfile);
if (!is_identifier(token)) {
parse_warn("expecting identifier.");
bad_flag:
if (token != SEMI)
skip_to_semi(cfile);
return (NULL);
}
if (!strcasecmp(val, "true") ||
!strcasecmp(val, "on"))
buf[0] = 1;
else if (!strcasecmp(val, "false") ||
!strcasecmp(val, "off"))
buf[0] = 0;
else {
parse_warn("expecting boolean.");
goto bad_flag;
}
len = 1;
dp = buf;
goto alloc;
default:
warning("Bad format %c in parse_option_param.",
*fmt);
skip_to_semi(cfile);
return (NULL);
}
}
token = next_token(&val, cfile);
} while (*fmt == 'A' && token == COMMA);
if (token != SEMI) {
parse_warn("semicolon expected.");
skip_to_semi(cfile);
return (NULL);
}
options[option->code].data = malloc(hunkix + nul_term);
if (!options[option->code].data)
error("out of memory allocating option data.");
memcpy(options[option->code].data, hunkbuf, hunkix + nul_term);
options[option->code].len = hunkix;
return (option);
}
void
parse_string_list(FILE *cfile, struct string_list **lp, int multiple)
{
int token;
char *val;
struct string_list *cur, *tmp;
/* Find the last medium in the media list. */
if (*lp)
for (cur = *lp; cur->next; cur = cur->next)
; /* nothing */
else
cur = NULL;
do {
token = next_token(&val, cfile);
if (token != STRING) {
parse_warn("Expecting media options.");
skip_to_semi(cfile);
return;
}
tmp = new_string_list(strlen(val) + 1);
if (tmp == NULL)
error("no memory for string list entry.");
strlcpy(tmp->string, val, strlen(val) + 1);
tmp->next = NULL;
/* Store this medium at the end of the media list. */
if (cur)
cur->next = tmp;
else
*lp = tmp;
cur = tmp;
token = next_token(&val, cfile);
} while (multiple && token == COMMA);
if (token != SEMI) {
parse_warn("expecting semicolon.");
skip_to_semi(cfile);
}
}
void
parse_reject_statement(FILE *cfile, struct client_config *config)
{
int token;
char *val;
struct iaddr addr;
struct iaddrlist *list;
do {
if (!parse_ip_addr(cfile, &addr)) {
parse_warn("expecting IP address.");
skip_to_semi(cfile);
return;
}
list = malloc(sizeof(struct iaddrlist));
if (!list)
error("no memory for reject list!");
list->addr = addr;
list->next = config->reject_list;
config->reject_list = list;
token = next_token(&val, cfile);
} while (token == COMMA);
if (token != SEMI) {
parse_warn("expecting semicolon.");
skip_to_semi(cfile);
}
}