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authorDenis Vlasenko <vda.linux@googlemail.com>2007-04-07 01:05:47 +0000
committerDenis Vlasenko <vda.linux@googlemail.com>2007-04-07 01:05:47 +0000
commitfbd2918f5c91723063ed698026217a77a0fe565b (patch)
treecddfe351592f4a876232cf4c67c23df25bf0563c /networking/udhcp
parentbb5b01c7c711dd9ffc2abf23a05ccdfbf7fc0325 (diff)
downloadbusybox-fbd2918f5c91723063ed698026217a77a0fe565b.tar.gz
udhcp: MAC_BCAST_ADDR and blank_chaddr are in fact constant, move to rodata.
a few global variables reduced to smallints function old new delta add_lease 75 227 +152 static.blank_chaddr - 16 +16 MAC_BCAST_ADDR - 6 +6 sockfd 4 8 +4 udhcp_run_script 1153 1155 +2 state 8 5 -3 listen_mode 4 1 -3 perform_release 152 148 -4 fd 8 4 -4 blank_chaddr 16 - -16 udhcpc_main 2518 2497 -21 .rodata 131864 131832 -32 oldest_expired_lease 61 - -61 clear_lease 127 - -127 ------------------------------------------------------------------------------ (add/remove: 2/3 grow/shrink: 3/6 up/down: 180/-271) Total: -91 bytes
Diffstat (limited to 'networking/udhcp')
-rw-r--r--networking/udhcp/common.c2
-rw-r--r--networking/udhcp/common.h6
-rw-r--r--networking/udhcp/dhcpc.c36
-rw-r--r--networking/udhcp/dhcpd.h83
-rw-r--r--networking/udhcp/leases.c68
-rw-r--r--networking/udhcp/options.h74
-rw-r--r--networking/udhcp/packet.c2
-rw-r--r--networking/udhcp/script.c52
-rw-r--r--networking/udhcp/serverpacket.c2
9 files changed, 169 insertions, 156 deletions
diff --git a/networking/udhcp/common.c b/networking/udhcp/common.c
index 46cc0348f..721888f6d 100644
--- a/networking/udhcp/common.c
+++ b/networking/udhcp/common.c
@@ -15,6 +15,8 @@
#include "common.h"
+const uint8_t MAC_BCAST_ADDR[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
+
long uptime(void)
{
struct sysinfo info;
diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h
index 00890ac1c..6c0db5b4c 100644
--- a/networking/udhcp/common.h
+++ b/networking/udhcp/common.h
@@ -14,8 +14,7 @@
#define DEFAULT_SCRIPT "/usr/share/udhcpc/default.script"
-#define COMBINED_BINARY
-
+extern const uint8_t MAC_BCAST_ADDR[6]; /* six all-ones */
/*** packet.h ***/
@@ -52,7 +51,8 @@ int udhcp_get_packet(struct dhcpMessage *packet, int fd);
uint16_t udhcp_checksum(void *addr, int count);
int udhcp_raw_packet(struct dhcpMessage *payload,
uint32_t source_ip, int source_port,
- uint32_t dest_ip, int dest_port, uint8_t *dest_arp, int ifindex);
+ uint32_t dest_ip, int dest_port,
+ const uint8_t *dest_arp, int ifindex);
int udhcp_kernel_packet(struct dhcpMessage *payload,
uint32_t source_ip, int source_port,
uint32_t dest_ip, int dest_port);
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index e8cdd79df..362e70169 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -17,22 +17,23 @@
#include "options.h"
-static int state;
/* Something is definitely wrong here. IPv4 addresses
* in variables of type long?? BTW, we use inet_ntoa()
* in the code. Manpage says that struct in_addr has a member of type long (!)
* which holds IPv4 address, and the struct is passed by value (!!)
*/
+static unsigned long timeout;
static unsigned long requested_ip; /* = 0 */
static uint32_t server_addr;
-static unsigned long timeout;
static int packet_num; /* = 0 */
-static int fd = -1;
+static int sockfd = -1;
#define LISTEN_NONE 0
#define LISTEN_KERNEL 1
#define LISTEN_RAW 2
-static int listen_mode;
+static smallint listen_mode;
+
+static smallint state;
struct client_config_t client_config;
@@ -42,8 +43,10 @@ static void change_mode(int new_mode)
{
DEBUG("entering %s listen mode",
new_mode ? (new_mode == 1 ? "kernel" : "raw") : "none");
- if (fd >= 0) close(fd);
- fd = -1;
+ if (sockfd >= 0) {
+ close(sockfd);
+ sockfd = -1;
+ }
listen_mode = new_mode;
}
@@ -111,6 +114,7 @@ static void client_background(void)
* If that will be properly disabled for NOMMU, client_background()
* will work on NOMMU too */
#else
+// chdir(/) is problematic. Imagine that e.g. pidfile name is RELATIVE! what will unlink do then, eh?
bb_daemonize(DAEMON_CHDIR_ROOT);
logmode &= ~LOGMODE_STDIO;
#endif
@@ -289,13 +293,13 @@ int udhcpc_main(int argc, char **argv)
tv.tv_sec = timeout - uptime();
tv.tv_usec = 0;
- if (listen_mode != LISTEN_NONE && fd < 0) {
+ if (listen_mode != LISTEN_NONE && sockfd < 0) {
if (listen_mode == LISTEN_KERNEL)
- fd = listen_socket(INADDR_ANY, CLIENT_PORT, client_config.interface);
+ sockfd = listen_socket(INADDR_ANY, CLIENT_PORT, client_config.interface);
else
- fd = raw_socket(client_config.ifindex);
+ sockfd = raw_socket(client_config.ifindex);
}
- max_fd = udhcp_sp_fd_set(&rfds, fd);
+ max_fd = udhcp_sp_fd_set(&rfds, sockfd);
if (tv.tv_sec > 0) {
DEBUG("Waiting on select...");
@@ -342,7 +346,8 @@ int udhcpc_main(int argc, char **argv)
packet_num++;
} else {
/* timed out, go back to init state */
- if (state == RENEW_REQUESTED) udhcp_run_script(NULL, "deconfig");
+ if (state == RENEW_REQUESTED)
+ udhcp_run_script(NULL, "deconfig");
state = INIT_SELECTING;
timeout = now;
packet_num = 0;
@@ -393,12 +398,12 @@ int udhcpc_main(int argc, char **argv)
timeout = 0x7fffffff;
break;
}
- } else if (retval > 0 && listen_mode != LISTEN_NONE && FD_ISSET(fd, &rfds)) {
+ } else if (retval > 0 && listen_mode != LISTEN_NONE && FD_ISSET(sockfd, &rfds)) {
/* a packet is ready, read it */
if (listen_mode == LISTEN_KERNEL)
- len = udhcp_get_packet(&packet, fd);
- else len = get_raw_packet(&packet, fd);
+ len = udhcp_get_packet(&packet, sockfd);
+ else len = get_raw_packet(&packet, sockfd);
if (len == -1 && errno != EINTR) {
DEBUG("error on read, %s, reopening socket", strerror(errno));
@@ -418,7 +423,8 @@ int udhcpc_main(int argc, char **argv)
continue;
}
- if ((message = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) {
+ message = get_option(&packet, DHCP_MESSAGE_TYPE);
+ if (message == NULL) {
bb_error_msg("cannot get option from packet - ignoring");
continue;
}
diff --git a/networking/udhcp/dhcpd.h b/networking/udhcp/dhcpd.h
index 40959e4ae..7c4fe695a 100644
--- a/networking/udhcp/dhcpd.h
+++ b/networking/udhcp/dhcpd.h
@@ -14,81 +14,6 @@
/* where to find the DHCP server configuration file */
#define DHCPD_CONF_FILE "/etc/udhcpd.conf"
-/*****************************************************************/
-/* Do not modify below here unless you know what you are doing!! */
-/*****************************************************************/
-
-/* DHCP protocol -- see RFC 2131 */
-#define SERVER_PORT 67
-#define CLIENT_PORT 68
-
-#define DHCP_MAGIC 0x63825363
-
-/* DHCP option codes (partial list) */
-#define DHCP_PADDING 0x00
-#define DHCP_SUBNET 0x01
-#define DHCP_TIME_OFFSET 0x02
-#define DHCP_ROUTER 0x03
-#define DHCP_TIME_SERVER 0x04
-#define DHCP_NAME_SERVER 0x05
-#define DHCP_DNS_SERVER 0x06
-#define DHCP_LOG_SERVER 0x07
-#define DHCP_COOKIE_SERVER 0x08
-#define DHCP_LPR_SERVER 0x09
-#define DHCP_HOST_NAME 0x0c
-#define DHCP_BOOT_SIZE 0x0d
-#define DHCP_DOMAIN_NAME 0x0f
-#define DHCP_SWAP_SERVER 0x10
-#define DHCP_ROOT_PATH 0x11
-#define DHCP_IP_TTL 0x17
-#define DHCP_MTU 0x1a
-#define DHCP_BROADCAST 0x1c
-#define DHCP_NTP_SERVER 0x2a
-#define DHCP_WINS_SERVER 0x2c
-#define DHCP_REQUESTED_IP 0x32
-#define DHCP_LEASE_TIME 0x33
-#define DHCP_OPTION_OVER 0x34
-#define DHCP_MESSAGE_TYPE 0x35
-#define DHCP_SERVER_ID 0x36
-#define DHCP_PARAM_REQ 0x37
-#define DHCP_MESSAGE 0x38
-#define DHCP_MAX_SIZE 0x39
-#define DHCP_T1 0x3a
-#define DHCP_T2 0x3b
-#define DHCP_VENDOR 0x3c
-#define DHCP_CLIENT_ID 0x3d
-#define DHCP_FQDN 0x51
-
-#define DHCP_END 0xFF
-
-
-#define BOOTREQUEST 1
-#define BOOTREPLY 2
-
-#define ETH_10MB 1
-#define ETH_10MB_LEN 6
-
-#define DHCPDISCOVER 1
-#define DHCPOFFER 2
-#define DHCPREQUEST 3
-#define DHCPDECLINE 4
-#define DHCPACK 5
-#define DHCPNAK 6
-#define DHCPRELEASE 7
-#define DHCPINFORM 8
-
-#define BROADCAST_FLAG 0x8000
-
-#define OPTION_FIELD 0
-#define FILE_FIELD 1
-#define SNAME_FIELD 2
-
-/* miscellaneous defines */
-#define MAC_BCAST_ADDR (uint8_t *) "\xff\xff\xff\xff\xff\xff"
-#define OPT_CODE 0
-#define OPT_LEN 1
-#define OPT_DATA 2
-
struct option_set {
uint8_t *data;
struct option_set *next;
@@ -140,13 +65,9 @@ struct dhcpOfferedAddr {
uint32_t expires; /* host order */
};
-extern uint8_t blank_chaddr[];
-
-void clear_lease(uint8_t *chaddr, uint32_t yiaddr);
-struct dhcpOfferedAddr *add_lease(uint8_t *chaddr, uint32_t yiaddr, unsigned long lease);
+struct dhcpOfferedAddr *add_lease(const uint8_t *chaddr, uint32_t yiaddr, unsigned long lease);
int lease_expired(struct dhcpOfferedAddr *lease);
-struct dhcpOfferedAddr *oldest_expired_lease(void);
-struct dhcpOfferedAddr *find_lease_by_chaddr(uint8_t *chaddr);
+struct dhcpOfferedAddr *find_lease_by_chaddr(const uint8_t *chaddr);
struct dhcpOfferedAddr *find_lease_by_yiaddr(uint32_t yiaddr);
uint32_t find_address(int check_expired);
diff --git a/networking/udhcp/leases.c b/networking/udhcp/leases.c
index 2f7847d74..5d8775f63 100644
--- a/networking/udhcp/leases.c
+++ b/networking/udhcp/leases.c
@@ -8,25 +8,41 @@
#include "dhcpd.h"
-uint8_t blank_chaddr[] = {[0 ... 15] = 0};
+/* Find the oldest expired lease, NULL if there are no expired leases */
+static struct dhcpOfferedAddr *oldest_expired_lease(void)
+{
+ struct dhcpOfferedAddr *oldest = NULL;
+ unsigned long oldest_lease = time(0);
+ unsigned i;
+
+
+ for (i = 0; i < server_config.max_leases; i++)
+ if (oldest_lease > leases[i].expires) {
+ oldest_lease = leases[i].expires;
+ oldest = &(leases[i]);
+ }
+ return oldest;
+}
+
/* clear every lease out that chaddr OR yiaddr matches and is nonzero */
-void clear_lease(uint8_t *chaddr, uint32_t yiaddr)
+static void clear_lease(const uint8_t *chaddr, uint32_t yiaddr)
{
- unsigned int i, j;
+ unsigned i, j;
for (j = 0; j < 16 && !chaddr[j]; j++);
for (i = 0; i < server_config.max_leases; i++)
- if ((j != 16 && !memcmp(leases[i].chaddr, chaddr, 16)) ||
- (yiaddr && leases[i].yiaddr == yiaddr)) {
+ if ((j != 16 && memcmp(leases[i].chaddr, chaddr, 16) != 0)
+ || (yiaddr && leases[i].yiaddr == yiaddr)
+ ) {
memset(&(leases[i]), 0, sizeof(struct dhcpOfferedAddr));
}
}
/* add a lease into the table, clearing out any old ones */
-struct dhcpOfferedAddr *add_lease(uint8_t *chaddr, uint32_t yiaddr, unsigned long lease)
+struct dhcpOfferedAddr *add_lease(const uint8_t *chaddr, uint32_t yiaddr, unsigned long lease)
{
struct dhcpOfferedAddr *oldest;
@@ -52,31 +68,14 @@ int lease_expired(struct dhcpOfferedAddr *lease)
}
-/* Find the oldest expired lease, NULL if there are no expired leases */
-struct dhcpOfferedAddr *oldest_expired_lease(void)
-{
- struct dhcpOfferedAddr *oldest = NULL;
- unsigned long oldest_lease = time(0);
- unsigned int i;
-
-
- for (i = 0; i < server_config.max_leases; i++)
- if (oldest_lease > leases[i].expires) {
- oldest_lease = leases[i].expires;
- oldest = &(leases[i]);
- }
- return oldest;
-
-}
-
-
/* Find the first lease that matches chaddr, NULL if no match */
-struct dhcpOfferedAddr *find_lease_by_chaddr(uint8_t *chaddr)
+struct dhcpOfferedAddr *find_lease_by_chaddr(const uint8_t *chaddr)
{
- unsigned int i;
+ unsigned i;
for (i = 0; i < server_config.max_leases; i++)
- if (!memcmp(leases[i].chaddr, chaddr, 16)) return &(leases[i]);
+ if (!memcmp(leases[i].chaddr, chaddr, 16))
+ return &(leases[i]);
return NULL;
}
@@ -85,10 +84,11 @@ struct dhcpOfferedAddr *find_lease_by_chaddr(uint8_t *chaddr)
/* Find the first lease that matches yiaddr, NULL is no match */
struct dhcpOfferedAddr *find_lease_by_yiaddr(uint32_t yiaddr)
{
- unsigned int i;
+ unsigned i;
for (i = 0; i < server_config.max_leases; i++)
- if (leases[i].yiaddr == yiaddr) return &(leases[i]);
+ if (leases[i].yiaddr == yiaddr)
+ return &(leases[i]);
return NULL;
}
@@ -97,6 +97,8 @@ struct dhcpOfferedAddr *find_lease_by_yiaddr(uint32_t yiaddr)
/* check is an IP is taken, if it is, add it to the lease table */
static int check_ip(uint32_t addr)
{
+ static const uint8_t blank_chaddr[16]; /* 16 zero bytes */
+
struct in_addr temp;
if (arpping(addr, server_config.server, server_config.arp, server_config.interface) == 0) {
@@ -105,7 +107,8 @@ static int check_ip(uint32_t addr)
inet_ntoa(temp), server_config.conflict_time);
add_lease(blank_chaddr, addr, server_config.conflict_time);
return 1;
- } else return 0;
+ }
+ return 0;
}
@@ -125,7 +128,7 @@ uint32_t find_address(int check_expired)
/* ie, 192.168.55.255 */
if ((addr & 0xFF) == 0xFF) continue;
- /* Only do if it isn't an assigned as a static lease */
+ /* Only do if it isn't assigned as a static lease */
if (!reservedIp(server_config.static_leases, htonl(addr))) {
/* lease is not taken */
@@ -133,11 +136,10 @@ uint32_t find_address(int check_expired)
lease = find_lease_by_yiaddr(ret);
/* no lease or it expired and we are checking for expired leases */
- if ( (!lease || (check_expired && lease_expired(lease)))
+ if ((!lease || (check_expired && lease_expired(lease)))
&& /* and it isn't on the network */ !check_ip(ret)
) {
return ret;
- break;
}
}
}
diff --git a/networking/udhcp/options.h b/networking/udhcp/options.h
index 11f013fd4..5e9adf881 100644
--- a/networking/udhcp/options.h
+++ b/networking/udhcp/options.h
@@ -23,6 +23,80 @@ enum {
#define OPTION_REQ 0x10 /* have the client request this option */
#define OPTION_LIST 0x20 /* There can be a list of 1 or more of these */
+/*****************************************************************/
+/* Do not modify below here unless you know what you are doing!! */
+/*****************************************************************/
+
+/* DHCP protocol -- see RFC 2131 */
+#define SERVER_PORT 67
+#define CLIENT_PORT 68
+
+#define DHCP_MAGIC 0x63825363
+
+/* DHCP option codes (partial list) */
+#define DHCP_PADDING 0x00
+#define DHCP_SUBNET 0x01
+#define DHCP_TIME_OFFSET 0x02
+#define DHCP_ROUTER 0x03
+#define DHCP_TIME_SERVER 0x04
+#define DHCP_NAME_SERVER 0x05
+#define DHCP_DNS_SERVER 0x06
+#define DHCP_LOG_SERVER 0x07
+#define DHCP_COOKIE_SERVER 0x08
+#define DHCP_LPR_SERVER 0x09
+#define DHCP_HOST_NAME 0x0c
+#define DHCP_BOOT_SIZE 0x0d
+#define DHCP_DOMAIN_NAME 0x0f
+#define DHCP_SWAP_SERVER 0x10
+#define DHCP_ROOT_PATH 0x11
+#define DHCP_IP_TTL 0x17
+#define DHCP_MTU 0x1a
+#define DHCP_BROADCAST 0x1c
+#define DHCP_NTP_SERVER 0x2a
+#define DHCP_WINS_SERVER 0x2c
+#define DHCP_REQUESTED_IP 0x32
+#define DHCP_LEASE_TIME 0x33
+#define DHCP_OPTION_OVER 0x34
+#define DHCP_MESSAGE_TYPE 0x35
+#define DHCP_SERVER_ID 0x36
+#define DHCP_PARAM_REQ 0x37
+#define DHCP_MESSAGE 0x38
+#define DHCP_MAX_SIZE 0x39
+#define DHCP_T1 0x3a
+#define DHCP_T2 0x3b
+#define DHCP_VENDOR 0x3c
+#define DHCP_CLIENT_ID 0x3d
+#define DHCP_FQDN 0x51
+
+#define DHCP_END 0xFF
+
+
+#define BOOTREQUEST 1
+#define BOOTREPLY 2
+
+#define ETH_10MB 1
+#define ETH_10MB_LEN 6
+
+#define DHCPDISCOVER 1
+#define DHCPOFFER 2
+#define DHCPREQUEST 3
+#define DHCPDECLINE 4
+#define DHCPACK 5
+#define DHCPNAK 6
+#define DHCPRELEASE 7
+#define DHCPINFORM 8
+
+#define BROADCAST_FLAG 0x8000
+
+#define OPTION_FIELD 0
+#define FILE_FIELD 1
+#define SNAME_FIELD 2
+
+/* miscellaneous defines */
+#define OPT_CODE 0
+#define OPT_LEN 1
+#define OPT_DATA 2
+
struct dhcp_option {
char name[12];
char flags;
diff --git a/networking/udhcp/packet.c b/networking/udhcp/packet.c
index 25c55faab..da3807773 100644
--- a/networking/udhcp/packet.c
+++ b/networking/udhcp/packet.c
@@ -112,7 +112,7 @@ uint16_t udhcp_checksum(void *addr, int count)
void BUG_sizeof_struct_udp_dhcp_packet_must_be_576(void);
int udhcp_raw_packet(struct dhcpMessage *payload,
uint32_t source_ip, int source_port,
- uint32_t dest_ip, int dest_port, uint8_t *dest_arp, int ifindex)
+ uint32_t dest_ip, int dest_port, const uint8_t *dest_arp, int ifindex)
{
int fd;
int result;
diff --git a/networking/udhcp/script.c b/networking/udhcp/script.c
index dc8ff7a1c..98706a592 100644
--- a/networking/udhcp/script.c
+++ b/networking/udhcp/script.c
@@ -9,7 +9,6 @@
*/
#include "common.h"
-#include "dhcpd.h"
#include "dhcpc.h"
#include "options.h"
@@ -77,7 +76,7 @@ static char *alloc_fill_opts(uint8_t *option, const struct dhcp_option *type_p)
switch (type) {
case OPTION_IP_PAIR:
dest += sprintip(dest, "", option);
- *(dest++) = '/';
+ *dest++ = '/';
option += 4;
optlen = 4;
case OPTION_IP: /* Works regardless of host byte order. */
@@ -132,34 +131,42 @@ static char **fill_envp(struct dhcpMessage *packet)
int num_options = 0;
int i, j;
char **envp;
+ char *var;
uint8_t *temp;
struct in_addr subnet;
char over = 0;
- if (packet == NULL)
- num_options = 0;
- else {
- for (i = 0; dhcp_options[i].code; i++)
+ if (packet) {
+ for (i = 0; dhcp_options[i].code; i++) {
if (get_option(packet, dhcp_options[i].code)) {
num_options++;
if (dhcp_options[i].code == DHCP_SUBNET)
num_options++; /* for mton */
}
- if (packet->siaddr) num_options++;
- if ((temp = get_option(packet, DHCP_OPTION_OVER)))
+ }
+ if (packet->siaddr)
+ num_options++;
+ temp = get_option(packet, DHCP_OPTION_OVER);
+ if (temp)
over = *temp;
- if (!(over & FILE_FIELD) && packet->file[0]) num_options++;
- if (!(over & SNAME_FIELD) && packet->sname[0]) num_options++;
+ if (!(over & FILE_FIELD) && packet->file[0])
+ num_options++;
+ if (!(over & SNAME_FIELD) && packet->sname[0])
+ num_options++;
}
envp = xzalloc(sizeof(char *) * (num_options + 5));
j = 0;
envp[j++] = xasprintf("interface=%s", client_config.interface);
- envp[j++] = xasprintf("PATH=%s",
- getenv("PATH") ? : "/bin:/usr/bin:/sbin:/usr/sbin");
- envp[j++] = xasprintf("HOME=%s", getenv("HOME") ? : "/");
+ var = getenv("PATH");
+ if (var)
+ envp[j++] = xasprintf("PATH=%s", var);
+ var = getenv("HOME");
+ if (var)
+ envp[j++] = xasprintf("HOME=%s", var);
- if (packet == NULL) return envp;
+ if (packet == NULL)
+ return envp;
envp[j] = xmalloc(sizeof("ip=255.255.255.255"));
sprintip(envp[j++], "ip=", (uint8_t *) &packet->yiaddr);
@@ -206,19 +213,20 @@ void udhcp_run_script(struct dhcpMessage *packet, const char *name)
DEBUG("vfork'ing and execle'ing %s", client_config.script);
envp = fill_envp(packet);
+
/* call script */
+// can we use wait4pid(spawn(...)) here?
pid = vfork();
- if (pid) {
- waitpid(pid, NULL, 0);
- for (curr = envp; *curr; curr++) free(*curr);
- free(envp);
- return;
- } else if (pid == 0) {
+ if (pid < 0) return;
+ if (pid == 0) {
/* close fd's? */
/* exec script */
execle(client_config.script, client_config.script,
name, NULL, envp);
- bb_perror_msg("script %s failed", client_config.script);
- exit(1);
+ bb_perror_msg_and_die("script %s failed", client_config.script);
}
+ waitpid(pid, NULL, 0);
+ for (curr = envp; *curr; curr++)
+ free(*curr);
+ free(envp);
}
diff --git a/networking/udhcp/serverpacket.c b/networking/udhcp/serverpacket.c
index 8889fda86..e1a88addd 100644
--- a/networking/udhcp/serverpacket.c
+++ b/networking/udhcp/serverpacket.c
@@ -38,7 +38,7 @@ static int send_packet_to_relay(struct dhcpMessage *payload)
/* send a packet to a specific arp address and ip address by creating our own ip packet */
static int send_packet_to_client(struct dhcpMessage *payload, int force_broadcast)
{
- uint8_t *chaddr;
+ const uint8_t *chaddr;
uint32_t ciaddr;
if (force_broadcast) {