774 lines
19 KiB
C
774 lines
19 KiB
C
/*
|
|
* dhcpcd - DHCP client daemon
|
|
* Copyright (c) 2006-2010 Roy Marples <roy@marples.name>
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
*/
|
|
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include "common.h"
|
|
#include "dhcp.h"
|
|
|
|
#define REQUEST (1 << 0)
|
|
#define UINT8 (1 << 1)
|
|
#define UINT16 (1 << 2)
|
|
#define SINT16 (1 << 3)
|
|
#define UINT32 (1 << 4)
|
|
#define SINT32 (1 << 5)
|
|
#define IPV4 (1 << 6)
|
|
#define STRING (1 << 7)
|
|
#define PAIR (1 << 8)
|
|
#define ARRAY (1 << 9)
|
|
#define RFC3361 (1 << 10)
|
|
#define RFC3397 (1 << 11)
|
|
#define RFC3442 (1 << 12)
|
|
|
|
#define IPV4R IPV4 | REQUEST
|
|
|
|
#define DAD "Duplicate address detected"
|
|
|
|
/* Our aggregate option buffer.
|
|
* We ONLY use this when options are split, which for most purposes is
|
|
* practically never. See RFC3396 for details. */
|
|
static uint8_t *opt_buffer;
|
|
|
|
struct dhcp_opt {
|
|
uint8_t option;
|
|
int type;
|
|
const char *var;
|
|
};
|
|
|
|
static const struct dhcp_opt dhcp_opts[] = {
|
|
{ 1, IPV4 | REQUEST, "subnet_mask" },
|
|
/* RFC 3442 states that the CSR has to come before all other
|
|
* routes. For completeness, we also specify static routes,
|
|
* then routers. */
|
|
{ 121, RFC3442, "classless_static_routes" },
|
|
{ 249, RFC3442, "ms_classless_static_routes" },
|
|
{ 33, IPV4 | ARRAY | REQUEST, "static_routes" },
|
|
{ 3, IPV4 | ARRAY | REQUEST, "routers" },
|
|
{ 2, UINT32, "time_offset" },
|
|
{ 4, IPV4 | ARRAY, "time_servers" },
|
|
{ 5, IPV4 | ARRAY, "ien116_name_servers" },
|
|
{ 6, IPV4 | ARRAY, "domain_name_servers" },
|
|
{ 7, IPV4 | ARRAY, "log_servers" },
|
|
{ 8, IPV4 | ARRAY, "cookie_servers" },
|
|
{ 9, IPV4 | ARRAY, "lpr_servers" },
|
|
{ 10, IPV4 | ARRAY, "impress_servers" },
|
|
{ 11, IPV4 | ARRAY, "resource_location_servers" },
|
|
{ 12, STRING, "host_name" },
|
|
{ 13, UINT16, "boot_size" },
|
|
{ 14, STRING, "merit_dump" },
|
|
{ 15, STRING, "domain_name" },
|
|
{ 16, IPV4, "swap_server" },
|
|
{ 17, STRING, "root_path" },
|
|
{ 18, STRING, "extensions_path" },
|
|
{ 19, UINT8, "ip_forwarding" },
|
|
{ 20, UINT8, "non_local_source_routing" },
|
|
{ 21, IPV4 | ARRAY, "policy_filter" },
|
|
{ 22, SINT16, "max_dgram_reassembly" },
|
|
{ 23, UINT16, "default_ip_ttl" },
|
|
{ 24, UINT32, "path_mtu_aging_timeout" },
|
|
{ 25, UINT16 | ARRAY, "path_mtu_plateau_table" },
|
|
{ 26, UINT16, "interface_mtu" },
|
|
{ 27, UINT8, "all_subnets_local" },
|
|
{ 28, IPV4 | REQUEST, "broadcast_address" },
|
|
{ 29, UINT8, "perform_mask_discovery" },
|
|
{ 30, UINT8, "mask_supplier" },
|
|
{ 31, UINT8, "router_discovery" },
|
|
{ 32, IPV4, "router_solicitation_address" },
|
|
{ 34, UINT8, "trailer_encapsulation" },
|
|
{ 35, UINT32, "arp_cache_timeout" },
|
|
{ 36, UINT16, "ieee802_3_encapsulation" },
|
|
{ 37, UINT8, "default_tcp_ttl" },
|
|
{ 38, UINT32, "tcp_keepalive_interval" },
|
|
{ 39, UINT8, "tcp_keepalive_garbage" },
|
|
{ 40, STRING, "nis_domain" },
|
|
{ 41, IPV4 | ARRAY, "nis_servers" },
|
|
{ 42, IPV4 | ARRAY, "ntp_servers" },
|
|
{ 43, STRING, "vendor_encapsulated_options" },
|
|
{ 44, IPV4 | ARRAY, "netbios_name_servers" },
|
|
{ 45, IPV4, "netbios_dd_server" },
|
|
{ 46, UINT8, "netbios_node_type" },
|
|
{ 47, STRING, "netbios_scope" },
|
|
{ 48, IPV4 | ARRAY, "font_servers" },
|
|
{ 49, IPV4 | ARRAY, "x_display_manager" },
|
|
{ 50, IPV4, "dhcp_requested_address" },
|
|
{ 51, UINT32 | REQUEST, "dhcp_lease_time" },
|
|
{ 52, UINT8, "dhcp_option_overload" },
|
|
{ 53, UINT8, "dhcp_message_type" },
|
|
{ 54, IPV4, "dhcp_server_identifier" },
|
|
{ 55, UINT8 | ARRAY, "dhcp_parameter_request_list" },
|
|
{ 56, STRING, "dhcp_message" },
|
|
{ 57, UINT16, "dhcp_max_message_size" },
|
|
{ 58, UINT32 | REQUEST, "dhcp_renewal_time" },
|
|
{ 59, UINT32 | REQUEST, "dhcp_rebinding_time" },
|
|
{ 64, STRING, "nisplus_domain" },
|
|
{ 65, IPV4 | ARRAY, "nisplus_servers" },
|
|
{ 66, STRING, "tftp_server_name" },
|
|
{ 67, STRING, "bootfile_name" },
|
|
{ 68, IPV4 | ARRAY, "mobile_ip_home_agent" },
|
|
{ 69, IPV4 | ARRAY, "smtp_server" },
|
|
{ 70, IPV4 | ARRAY, "pop_server" },
|
|
{ 71, IPV4 | ARRAY, "nntp_server" },
|
|
{ 72, IPV4 | ARRAY, "www_server" },
|
|
{ 73, IPV4 | ARRAY, "finger_server" },
|
|
{ 74, IPV4 | ARRAY, "irc_server" },
|
|
{ 75, IPV4 | ARRAY, "streettalk_server" },
|
|
{ 76, IPV4 | ARRAY, "streettalk_directory_assistance_server" },
|
|
{ 77, STRING, "user_class" },
|
|
{ 81, STRING | RFC3397, "fqdn_name" },
|
|
{ 85, IPV4 | ARRAY, "nds_servers" },
|
|
{ 86, STRING, "nds_tree_name" },
|
|
{ 87, STRING, "nds_context" },
|
|
{ 88, STRING | RFC3397, "bcms_controller_names" },
|
|
{ 89, IPV4 | ARRAY, "bcms_controller_address" },
|
|
{ 91, UINT32, "client_last_transaction_time" },
|
|
{ 92, IPV4 | ARRAY, "associated_ip" },
|
|
{ 98, STRING, "uap_servers" },
|
|
{ 112, IPV4 | ARRAY, "netinfo_server_address" },
|
|
{ 113, STRING, "netinfo_server_tag" },
|
|
{ 114, STRING, "default_url" },
|
|
{ 118, IPV4, "subnet_selection" },
|
|
{ 119, STRING | RFC3397, "domain_search" },
|
|
{ 0, 0, NULL }
|
|
};
|
|
|
|
static int
|
|
valid_length(uint8_t option, int dl, int *type)
|
|
{
|
|
const struct dhcp_opt *opt;
|
|
ssize_t sz;
|
|
|
|
if (dl == 0)
|
|
return -1;
|
|
|
|
for (opt = dhcp_opts; opt->option; opt++) {
|
|
if (opt->option != option)
|
|
continue;
|
|
|
|
if (type)
|
|
*type = opt->type;
|
|
|
|
if (opt->type == 0 ||
|
|
opt->type & STRING ||
|
|
opt->type & RFC3442)
|
|
return 0;
|
|
|
|
sz = 0;
|
|
if (opt->type & UINT32 || opt->type & IPV4)
|
|
sz = sizeof(uint32_t);
|
|
if (opt->type & UINT16)
|
|
sz = sizeof(uint16_t);
|
|
if (opt->type & UINT8)
|
|
sz = sizeof(uint8_t);
|
|
if (opt->type & IPV4 || opt->type & ARRAY)
|
|
return dl % sz;
|
|
return (dl == sz ? 0 : -1);
|
|
}
|
|
|
|
/* unknown option, so let it pass */
|
|
return 0;
|
|
}
|
|
|
|
#ifdef DEBUG_MEMORY
|
|
static void
|
|
free_option_buffer(void)
|
|
{
|
|
free(opt_buffer);
|
|
}
|
|
#endif
|
|
|
|
#define get_option_raw(dhcp, opt) get_option(dhcp, opt, NULL, NULL)
|
|
static const uint8_t *
|
|
get_option(const struct dhcp_message *dhcp, uint8_t opt, int *len, int *type)
|
|
{
|
|
const uint8_t *p = dhcp->options;
|
|
const uint8_t *e = p + sizeof(dhcp->options);
|
|
uint8_t l, ol = 0;
|
|
uint8_t o = 0;
|
|
uint8_t overl = 0;
|
|
uint8_t *bp = NULL;
|
|
const uint8_t *op = NULL;
|
|
int bl = 0;
|
|
|
|
while (p < e) {
|
|
o = *p++;
|
|
if (o == opt) {
|
|
if (op) {
|
|
if (!opt_buffer) {
|
|
opt_buffer = xmalloc(sizeof(*dhcp));
|
|
#ifdef DEBUG_MEMORY
|
|
atexit(free_option_buffer);
|
|
#endif
|
|
}
|
|
if (!bp)
|
|
bp = opt_buffer;
|
|
memcpy(bp, op, ol);
|
|
bp += ol;
|
|
}
|
|
ol = *p;
|
|
op = p + 1;
|
|
bl += ol;
|
|
}
|
|
switch (o) {
|
|
case DHO_PAD:
|
|
continue;
|
|
case DHO_END:
|
|
if (overl & 1) {
|
|
/* bit 1 set means parse boot file */
|
|
overl &= ~1;
|
|
p = dhcp->bootfile;
|
|
e = p + sizeof(dhcp->bootfile);
|
|
} else if (overl & 2) {
|
|
/* bit 2 set means parse server name */
|
|
overl &= ~2;
|
|
p = dhcp->servername;
|
|
e = p + sizeof(dhcp->servername);
|
|
} else
|
|
goto exit;
|
|
break;
|
|
case DHO_OPTIONSOVERLOADED:
|
|
/* Ensure we only get this option once */
|
|
if (!overl)
|
|
overl = p[1];
|
|
break;
|
|
}
|
|
l = *p++;
|
|
p += l;
|
|
}
|
|
|
|
exit:
|
|
if (valid_length(opt, bl, type) == -1) {
|
|
errno = EINVAL;
|
|
return NULL;
|
|
}
|
|
if (len)
|
|
*len = bl;
|
|
if (bp) {
|
|
memcpy(bp, op, ol);
|
|
return (const uint8_t *)opt_buffer;
|
|
}
|
|
if (op)
|
|
return op;
|
|
errno = ENOENT;
|
|
return NULL;
|
|
}
|
|
|
|
int
|
|
get_option_addr(struct in_addr *a, const struct dhcp_message *dhcp,
|
|
uint8_t option)
|
|
{
|
|
const uint8_t *p = get_option_raw(dhcp, option);
|
|
|
|
if (!p)
|
|
return -1;
|
|
memcpy(&a->s_addr, p, sizeof(a->s_addr));
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
get_option_uint32(uint32_t *i, const struct dhcp_message *dhcp, uint8_t option)
|
|
{
|
|
const uint8_t *p = get_option_raw(dhcp, option);
|
|
uint32_t d;
|
|
|
|
if (!p)
|
|
return -1;
|
|
memcpy(&d, p, sizeof(d));
|
|
*i = ntohl(d);
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
get_option_uint16(uint16_t *i, const struct dhcp_message *dhcp, uint8_t option)
|
|
{
|
|
const uint8_t *p = get_option_raw(dhcp, option);
|
|
uint16_t d;
|
|
|
|
if (!p)
|
|
return -1;
|
|
memcpy(&d, p, sizeof(d));
|
|
*i = ntohs(d);
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
get_option_uint8(uint8_t *i, const struct dhcp_message *dhcp, uint8_t option)
|
|
{
|
|
const uint8_t *p = get_option_raw(dhcp, option);
|
|
|
|
if (!p)
|
|
return -1;
|
|
if (i)
|
|
*i = *(p);
|
|
return 0;
|
|
}
|
|
|
|
static struct rt *
|
|
decode_rfc3442_rt(int dl, const uint8_t *data)
|
|
{
|
|
const uint8_t *p = data;
|
|
const uint8_t *e;
|
|
uint8_t cidr;
|
|
size_t ocets;
|
|
struct rt *routes = NULL;
|
|
struct rt *rt = NULL;
|
|
|
|
/* Minimum is 5 -first is CIDR and a router length of 4 */
|
|
if (dl < 5)
|
|
return NULL;
|
|
|
|
e = p + dl;
|
|
while (p < e) {
|
|
cidr = *p++;
|
|
if (cidr > 32) {
|
|
free_routes(routes);
|
|
errno = EINVAL;
|
|
return NULL;
|
|
}
|
|
|
|
if (rt) {
|
|
rt->next = xzalloc(sizeof(*rt));
|
|
rt = rt->next;
|
|
} else {
|
|
routes = rt = xzalloc(sizeof(*routes));
|
|
}
|
|
rt->next = NULL;
|
|
|
|
ocets = (cidr + 7) / 8;
|
|
/* If we have ocets then we have a destination and netmask */
|
|
if (ocets > 0) {
|
|
memcpy(&rt->dest.s_addr, p, ocets);
|
|
p += ocets;
|
|
rt->net.s_addr = htonl(~0U << (32 - cidr));
|
|
}
|
|
|
|
/* Finally, snag the router */
|
|
memcpy(&rt->gate.s_addr, p, 4);
|
|
p += 4;
|
|
}
|
|
return routes;
|
|
}
|
|
|
|
|
|
/* This calculates the netmask that we should use for static routes.
|
|
* This IS different from the calculation used to calculate the netmask
|
|
* for an interface address. */
|
|
static uint32_t
|
|
route_netmask(uint32_t ip_in)
|
|
{
|
|
/* used to be unsigned long - check if error */
|
|
uint32_t p = ntohl(ip_in);
|
|
uint32_t t;
|
|
|
|
if (IN_CLASSA(p))
|
|
t = ~IN_CLASSA_NET;
|
|
else {
|
|
if (IN_CLASSB(p))
|
|
t = ~IN_CLASSB_NET;
|
|
else {
|
|
if (IN_CLASSC(p))
|
|
t = ~IN_CLASSC_NET;
|
|
else
|
|
t = 0;
|
|
}
|
|
}
|
|
|
|
while (t & p)
|
|
t >>= 1;
|
|
|
|
return (htonl(~t));
|
|
}
|
|
|
|
/* We need to obey routing options.
|
|
* If we have a CSR then we only use that.
|
|
* Otherwise we add static routes and then routers. */
|
|
struct rt *
|
|
get_option_routes(const struct dhcp_message *dhcp,
|
|
const char *ifname, int *opts)
|
|
{
|
|
const uint8_t *p;
|
|
const uint8_t *e;
|
|
struct rt *routes = NULL;
|
|
struct rt *route = NULL;
|
|
int len;
|
|
|
|
/* If we have CSR's then we MUST use these only */
|
|
p = get_option(dhcp, DHO_CSR, &len, NULL);
|
|
/* Check for crappy MS option */
|
|
if (!p)
|
|
p = get_option(dhcp, DHO_MSCSR, &len, NULL);
|
|
if (p) {
|
|
routes = decode_rfc3442_rt(len, p);
|
|
if (routes && !(*opts & DHCPCD_CSR_WARNED)) {
|
|
*opts |= DHCPCD_CSR_WARNED;
|
|
return routes;
|
|
}
|
|
}
|
|
|
|
/* OK, get our static routes first. */
|
|
p = get_option(dhcp, DHO_STATICROUTE, &len, NULL);
|
|
if (p) {
|
|
e = p + len;
|
|
while (p < e) {
|
|
if (route) {
|
|
route->next = xmalloc(sizeof(*route));
|
|
route = route->next;
|
|
} else
|
|
routes = route = xmalloc(sizeof(*routes));
|
|
route->next = NULL;
|
|
memcpy(&route->dest.s_addr, p, 4);
|
|
p += 4;
|
|
memcpy(&route->gate.s_addr, p, 4);
|
|
p += 4;
|
|
route->net.s_addr = route_netmask(route->dest.s_addr);
|
|
}
|
|
}
|
|
|
|
/* Now grab our routers */
|
|
p = get_option(dhcp, DHO_ROUTER, &len, NULL);
|
|
if (p) {
|
|
e = p + len;
|
|
while (p < e) {
|
|
if (route) {
|
|
route->next = xzalloc(sizeof(*route));
|
|
route = route->next;
|
|
} else
|
|
routes = route = xzalloc(sizeof(*route));
|
|
memcpy(&route->gate.s_addr, p, 4);
|
|
p += 4;
|
|
}
|
|
}
|
|
|
|
return routes;
|
|
}
|
|
|
|
static size_t
|
|
encode_rfc1035(const char *src, uint8_t *dst)
|
|
{
|
|
uint8_t *p = dst;
|
|
uint8_t *lp = p++;
|
|
|
|
if (*src == '\0')
|
|
return 0;
|
|
for (; *src; src++) {
|
|
if (*src == '\0')
|
|
break;
|
|
if (*src == '.') {
|
|
/* Skip the trailing . */
|
|
if (src[1] == '\0')
|
|
break;
|
|
*lp = p - lp - 1;
|
|
if (*lp == '\0')
|
|
return p - dst;
|
|
lp = p++;
|
|
} else
|
|
*p++ = (uint8_t)*src;
|
|
}
|
|
*lp = p - lp - 1;
|
|
*p++ = '\0';
|
|
return p - dst;
|
|
}
|
|
|
|
#define PUTADDR(_type, _val) \
|
|
{ \
|
|
*p++ = _type; \
|
|
*p++ = 4; \
|
|
memcpy(p, &_val.s_addr, 4); \
|
|
p += 4; \
|
|
}
|
|
|
|
int
|
|
dhcp_message_add_addr(struct dhcp_message *dhcp,
|
|
uint8_t type, struct in_addr addr)
|
|
{
|
|
uint8_t *p;
|
|
size_t len;
|
|
|
|
p = dhcp->options;
|
|
while (*p != DHO_END) {
|
|
p++;
|
|
p += *p + 1;
|
|
}
|
|
|
|
len = p - (uint8_t *)dhcp;
|
|
if (len + 6 > sizeof(*dhcp)) {
|
|
errno = ENOMEM;
|
|
return -1;
|
|
}
|
|
|
|
PUTADDR(type, addr);
|
|
*p = DHO_END;
|
|
return 0;
|
|
}
|
|
|
|
ssize_t
|
|
make_message(struct dhcp_message **message,
|
|
const struct interface *iface,
|
|
uint8_t type)
|
|
{
|
|
struct dhcp_message *dhcp;
|
|
uint8_t *m, *lp, *p;
|
|
uint8_t *n_params = NULL;
|
|
time_t up = uptime() - iface->start_uptime;
|
|
uint32_t ul;
|
|
uint16_t sz;
|
|
size_t len;
|
|
const char *hp;
|
|
const struct dhcp_opt *opt;
|
|
const struct if_options *ifo = iface->state->options;
|
|
const struct dhcp_lease *lease = &iface->state->lease;
|
|
|
|
dhcp = xzalloc(sizeof (*dhcp));
|
|
m = (uint8_t *)dhcp;
|
|
p = dhcp->options;
|
|
|
|
if ((type == DHCP_INFORM || type == DHCP_RELEASE ||
|
|
(type == DHCP_REQUEST &&
|
|
iface->net.s_addr == lease->net.s_addr &&
|
|
(iface->state->new == NULL ||
|
|
iface->state->new->cookie == htonl(MAGIC_COOKIE)))))
|
|
{
|
|
dhcp->ciaddr = iface->addr.s_addr;
|
|
/* In-case we haven't actually configured the address yet */
|
|
if (type == DHCP_INFORM && iface->addr.s_addr == 0)
|
|
dhcp->ciaddr = lease->addr.s_addr;
|
|
}
|
|
|
|
dhcp->op = DHCP_BOOTREQUEST;
|
|
dhcp->hwtype = iface->family;
|
|
switch (iface->family) {
|
|
case ARPHRD_ETHER:
|
|
case ARPHRD_IEEE802:
|
|
dhcp->hwlen = iface->hwlen;
|
|
memcpy(&dhcp->chaddr, &iface->hwaddr, iface->hwlen);
|
|
break;
|
|
}
|
|
|
|
if (ifo->options & DHCPCD_BROADCAST &&
|
|
dhcp->ciaddr == 0 &&
|
|
type != DHCP_DECLINE &&
|
|
type != DHCP_RELEASE)
|
|
dhcp->flags = htons(BROADCAST_FLAG);
|
|
|
|
if (type != DHCP_DECLINE && type != DHCP_RELEASE) {
|
|
if (up < 0 || up > (time_t)UINT16_MAX)
|
|
dhcp->secs = htons((uint16_t)UINT16_MAX);
|
|
else
|
|
dhcp->secs = htons(up);
|
|
}
|
|
dhcp->xid = iface->state->xid;
|
|
dhcp->cookie = htonl(MAGIC_COOKIE);
|
|
|
|
*p++ = DHO_MESSAGETYPE;
|
|
*p++ = 1;
|
|
*p++ = type;
|
|
|
|
if (iface->clientid) {
|
|
*p++ = DHO_CLIENTID;
|
|
memcpy(p, iface->clientid, iface->clientid[0] + 1);
|
|
p += iface->clientid[0] + 1;
|
|
}
|
|
|
|
if (lease->addr.s_addr && lease->cookie == htonl(MAGIC_COOKIE)) {
|
|
if (type == DHCP_DECLINE ||
|
|
(type == DHCP_REQUEST &&
|
|
lease->addr.s_addr != iface->addr.s_addr))
|
|
{
|
|
PUTADDR(DHO_IPADDRESS, lease->addr);
|
|
if (lease->server.s_addr)
|
|
PUTADDR(DHO_SERVERID, lease->server);
|
|
}
|
|
|
|
if (type == DHCP_RELEASE) {
|
|
if (lease->server.s_addr)
|
|
PUTADDR(DHO_SERVERID, lease->server);
|
|
}
|
|
}
|
|
|
|
if (type == DHCP_DECLINE) {
|
|
*p++ = DHO_MESSAGE;
|
|
len = strlen(DAD);
|
|
*p++ = len;
|
|
memcpy(p, DAD, len);
|
|
p += len;
|
|
}
|
|
|
|
if (type == DHCP_DISCOVER && ifo->options & DHCPCD_REQUEST)
|
|
PUTADDR(DHO_IPADDRESS, ifo->req_addr);
|
|
|
|
if (type == DHCP_DISCOVER ||
|
|
type == DHCP_INFORM ||
|
|
type == DHCP_REQUEST)
|
|
{
|
|
*p++ = DHO_MAXMESSAGESIZE;
|
|
*p++ = 2;
|
|
sz = get_mtu(iface->name);
|
|
if (sz < MTU_MIN) {
|
|
if (set_mtu(iface->name, MTU_MIN) == 0)
|
|
sz = MTU_MIN;
|
|
} else if (sz > MTU_MAX) {
|
|
/* Even though our MTU could be greater than
|
|
* MTU_MAX (1500) dhcpcd does not presently
|
|
* handle DHCP packets any bigger. */
|
|
sz = MTU_MAX;
|
|
}
|
|
sz = htons(sz);
|
|
memcpy(p, &sz, 2);
|
|
p += 2;
|
|
|
|
if (ifo->userclass[0]) {
|
|
*p++ = DHO_USERCLASS;
|
|
memcpy(p, ifo->userclass, ifo->userclass[0] + 1);
|
|
p += ifo->userclass[0] + 1;
|
|
}
|
|
|
|
if (ifo->vendorclassid[0]) {
|
|
*p++ = DHO_VENDORCLASSID;
|
|
memcpy(p, ifo->vendorclassid,
|
|
ifo->vendorclassid[0] + 1);
|
|
p += ifo->vendorclassid[0] + 1;
|
|
}
|
|
|
|
|
|
if (type != DHCP_INFORM) {
|
|
if (ifo->leasetime != 0) {
|
|
*p++ = DHO_LEASETIME;
|
|
*p++ = 4;
|
|
ul = htonl(ifo->leasetime);
|
|
memcpy(p, &ul, 4);
|
|
p += 4;
|
|
}
|
|
}
|
|
|
|
/* Regardless of RFC2132, we should always send a hostname
|
|
* upto the first dot (the short hostname) as otherwise
|
|
* confuses some DHCP servers when updating DNS.
|
|
* The FQDN option should be used if a FQDN is required. */
|
|
if (ifo->options & DHCPCD_HOSTNAME && ifo->hostname[0]) {
|
|
*p++ = DHO_HOSTNAME;
|
|
hp = strchr(ifo->hostname, '.');
|
|
if (hp)
|
|
len = hp - ifo->hostname;
|
|
else
|
|
len = strlen(ifo->hostname);
|
|
*p++ = len;
|
|
memcpy(p, ifo->hostname, len);
|
|
p += len;
|
|
}
|
|
if (ifo->fqdn != FQDN_DISABLE && ifo->hostname[0]) {
|
|
/* IETF DHC-FQDN option (81), RFC4702 */
|
|
*p++ = DHO_FQDN;
|
|
lp = p;
|
|
*p++ = 3;
|
|
/*
|
|
* Flags: 0000NEOS
|
|
* S: 1 => Client requests Server to update
|
|
* a RR in DNS as well as PTR
|
|
* O: 1 => Server indicates to client that
|
|
* DNS has been updated
|
|
* E: 1 => Name data is DNS format
|
|
* N: 1 => Client requests Server to not
|
|
* update DNS
|
|
*/
|
|
*p++ = (ifo->fqdn & 0x09) | 0x04;
|
|
*p++ = 0; /* from server for PTR RR */
|
|
*p++ = 0; /* from server for A RR if S=1 */
|
|
ul = encode_rfc1035(ifo->hostname, p);
|
|
*lp += ul;
|
|
p += ul;
|
|
}
|
|
|
|
/* vendor is already encoded correctly, so just add it */
|
|
if (ifo->vendor[0]) {
|
|
*p++ = DHO_VENDOR;
|
|
memcpy(p, ifo->vendor, ifo->vendor[0] + 1);
|
|
p += ifo->vendor[0] + 1;
|
|
}
|
|
|
|
*p++ = DHO_PARAMETERREQUESTLIST;
|
|
n_params = p;
|
|
*p++ = 0;
|
|
for (opt = dhcp_opts; opt->option; opt++) {
|
|
if (!(opt->type & REQUEST ||
|
|
has_option_mask(ifo->requestmask, opt->option)))
|
|
continue;
|
|
if (type == DHCP_INFORM &&
|
|
(opt->option == DHO_RENEWALTIME ||
|
|
opt->option == DHO_REBINDTIME))
|
|
continue;
|
|
*p++ = opt->option;
|
|
}
|
|
*n_params = p - n_params - 1;
|
|
}
|
|
*p++ = DHO_END;
|
|
|
|
#ifdef BOOTP_MESSAGE_LENTH_MIN
|
|
/* Some crappy DHCP servers think they have to obey the BOOTP minimum
|
|
* message length.
|
|
* They are wrong, but we should still cater for them. */
|
|
while (p - m < BOOTP_MESSAGE_LENTH_MIN)
|
|
*p++ = DHO_PAD;
|
|
#endif
|
|
|
|
*message = dhcp;
|
|
return p - m;
|
|
}
|
|
|
|
void
|
|
get_lease(struct dhcp_lease *lease, const struct dhcp_message *dhcp)
|
|
{
|
|
struct timeval now;
|
|
|
|
lease->cookie = dhcp->cookie;
|
|
/* BOOTP does not set yiaddr for replies when ciaddr is set. */
|
|
if (dhcp->yiaddr)
|
|
lease->addr.s_addr = dhcp->yiaddr;
|
|
else
|
|
lease->addr.s_addr = dhcp->ciaddr;
|
|
if (get_option_addr(&lease->net, dhcp, DHO_SUBNETMASK) == -1)
|
|
lease->net.s_addr = get_netmask(lease->addr.s_addr);
|
|
if (get_option_addr(&lease->brd, dhcp, DHO_BROADCAST) == -1)
|
|
lease->brd.s_addr = lease->addr.s_addr | ~lease->net.s_addr;
|
|
if (get_option_uint32(&lease->leasetime, dhcp, DHO_LEASETIME) == 0) {
|
|
/* Ensure that we can use the lease */
|
|
get_monotonic(&now);
|
|
if (now.tv_sec + (time_t)lease->leasetime < now.tv_sec)
|
|
lease->leasetime = ~0U; /* Infinite lease */
|
|
} else
|
|
lease->leasetime = ~0U; /* Default to infinite lease */
|
|
if (get_option_uint32(&lease->renewaltime, dhcp, DHO_RENEWALTIME) != 0)
|
|
lease->renewaltime = 0;
|
|
if (get_option_uint32(&lease->rebindtime, dhcp, DHO_REBINDTIME) != 0)
|
|
lease->rebindtime = 0;
|
|
if (get_option_addr(&lease->server, dhcp, DHO_SERVERID) != 0)
|
|
lease->server.s_addr = INADDR_ANY;
|
|
}
|