[PATCH 4/8] net: dhcp: factorise setting option code
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Mon Apr 2 10:19:06 EDT 2012
This will allow to add more easly new option with less impact in the binary.
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
net/dhcp.c | 121 +++++++++++++++++++++++++++++++++++++++++++-----------------
1 files changed, 87 insertions(+), 34 deletions(-)
diff --git a/net/dhcp.c b/net/dhcp.c
index 12df542..7d01d4b 100644
--- a/net/dhcp.c
+++ b/net/dhcp.c
@@ -227,6 +227,79 @@ struct dhcp_opt dhcp_options[] = {
},
};
+struct dhcp_param {
+ unsigned char option;
+ const char *barebox_var_name;
+ int (*handle)(struct dhcp_param *param, u8 *e);
+ void *data;
+};
+
+static int dhcp_set_string_options(struct dhcp_param *param, u8 *e)
+{
+ int str_len;
+ char* str = param->data;
+
+ if (!str && param->barebox_var_name)
+ str = (char*)getenv(param->barebox_var_name);
+
+ if (!str)
+ return 0;
+
+ str_len = strlen(str);
+ if (!str_len)
+ return 0;
+
+ *e++ = param->option;
+ *e++ = str_len;
+ memcpy(e, str, str_len);
+
+ return str_len + 2;
+}
+
+#define DHCP_VENDOR_ID 60
+
+struct dhcp_param dhcp_params[] = {
+ {
+ .option = DHCP_VENDOR_ID,
+ .handle = dhcp_set_string_options,
+ .barebox_var_name = "dhcp_vendor_id",
+ }
+};
+
+static void dhcp_set_param_data(int option, void* data)
+{
+ struct dhcp_param *param;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dhcp_params); i++) {
+ param = &dhcp_params[i];
+
+ if (param->option == option) {
+ param->data = data;
+ return;
+ }
+ }
+}
+
+static int dhcp_set_ip_options(int option, u8 *e, IPaddr_t ip)
+{
+ int tmp;
+
+ if (!ip)
+ return 0;
+
+ tmp = ntohl(ip);
+
+ *e++ = option;
+ *e++ = 4;
+ *e++ = tmp >> 24;
+ *e++ = tmp >> 16;
+ *e++ = tmp >> 8;
+ *e++ = tmp & 0xff;
+
+ return 6;
+}
+
static int bootp_check_packet(unsigned char *pkt, unsigned src, unsigned len)
{
struct bootp *bp = (struct bootp *) pkt;
@@ -280,12 +353,11 @@ static void bootp_copy_net_params(struct bootp *bp)
* Initialize BOOTP extension fields in the request.
*/
static int dhcp_extended (u8 *e, int message_type, IPaddr_t ServerID,
- IPaddr_t RequestedIP, char *vendor_id)
+ IPaddr_t RequestedIP)
{
int i;
u8 *start = e;
u8 *cnt;
- int vendor_id_len = vendor_id ? strlen(vendor_id) : 0;
*e++ = 99; /* RFC1048 Magic Cookie */
*e++ = 130;
@@ -301,34 +373,12 @@ static int dhcp_extended (u8 *e, int message_type, IPaddr_t ServerID,
*e++ = (576 - 312 + OPT_SIZE) >> 8;
*e++ = (576 - 312 + OPT_SIZE) & 0xff;
- if (ServerID) {
- int tmp = ntohl (ServerID);
-
- *e++ = 54; /* ServerID */
- *e++ = 4;
- *e++ = tmp >> 24;
- *e++ = tmp >> 16;
- *e++ = tmp >> 8;
- *e++ = tmp & 0xff;
- }
- if (RequestedIP) {
- int tmp = ntohl (RequestedIP);
+ e += dhcp_set_ip_options(50, e, RequestedIP);
+ e += dhcp_set_ip_options(54, e, ServerID);
- *e++ = 50; /* Requested IP */
- *e++ = 4;
- *e++ = tmp >> 24;
- *e++ = tmp >> 16;
- *e++ = tmp >> 8;
- *e++ = tmp & 0xff;
- }
-
- if (vendor_id_len > 0) {
- *e++ = 60;
- *e++ = vendor_id_len;
- memcpy(e, vendor_id, vendor_id_len);
- e += vendor_id_len;
- }
+ for (i = 0; i < ARRAY_SIZE(dhcp_params); i++)
+ e += dhcp_params[i].handle(&dhcp_params[i], e);
*e++ = 55; /* Parameter Request List */
cnt = e++; /* Pointer to count of requested items */
@@ -380,8 +430,7 @@ static int bootp_request(void)
safe_strncpy (bp->bp_file, bfile, sizeof(bp->bp_file));
/* Request additional information from the BOOTP/DHCP server */
- ext_len = dhcp_extended((u8 *)bp->bp_vend, DHCP_DISCOVER, 0, 0,
- dhcp_con->priv);
+ ext_len = dhcp_extended((u8 *)bp->bp_vend, DHCP_DISCOVER, 0, 0);
Bootp_id = (uint32_t)get_time_ns();
net_copy_uint32(&bp->bp_id, &Bootp_id);
@@ -486,7 +535,7 @@ static void dhcp_send_request_packet(struct bootp *bp_offer)
*/
net_copy_ip(&OfferedIP, &bp->bp_yiaddr);
extlen = dhcp_extended((u8 *)bp->bp_vend, DHCP_REQUEST, net_dhcp_server_ip,
- OfferedIP, dhcp_con->priv);
+ OfferedIP);
debug("Transmitting DHCPREQUEST packet\n");
net_udp_send(dhcp_con, sizeof(*bp) + extlen);
@@ -566,19 +615,18 @@ static void dhcp_reset_env(void)
static int do_dhcp(int argc, char *argv[])
{
int ret, opt;
- char *vendor_id = (char*)getenv("dhcp_vendor_id");
dhcp_reset_env();
while((opt = getopt(argc, argv, "v:")) > 0) {
switch(opt) {
case 'v':
- vendor_id = optarg;
+ dhcp_set_param_data(DHCP_VENDOR_ID, optarg);
break;
}
}
- dhcp_con = net_udp_new(0xffffffff, PORT_BOOTPS, dhcp_handler, vendor_id);
+ dhcp_con = net_udp_new(0xffffffff, PORT_BOOTPS, dhcp_handler, NULL);
if (IS_ERR(dhcp_con)) {
ret = PTR_ERR(dhcp_con);
goto out;
@@ -622,6 +670,10 @@ BAREBOX_CMD_HELP_SHORT("Invoke dhcp client to obtain ip/boot params.\n")
BAREBOX_CMD_HELP_OPT ("-v <vendor_id>",
"DHCP Vendor ID (code 60) submitted in DHCP requests. It can\n"
"be used in the DHCP server's configuration to select options\n"
+"(e.g. bootfile or server) which are valid for barebox clients only.\n")
+BAREBOX_CMD_HELP_OPT ("-c <client_id>",
+"DHCP Client ID (code 61) submitted in DHCP requests. It can\n"
+"be used in the DHCP server's configuration to select options\n"
"(e.g. bootfile or server) which are valid for barebox clients only.\n");
BAREBOX_CMD_HELP_END
@@ -637,4 +689,5 @@ BAREBOX_MAGICVAR(hostname, "hostname returned from DHCP request");
BAREBOX_MAGICVAR(domainname, "domainname returned from DHCP request");
BAREBOX_MAGICVAR(rootpath, "rootpath returned from DHCP request");
BAREBOX_MAGICVAR(dhcp_vendor_id, "vendor id to send to the DHCP server");
+BAREBOX_MAGICVAR(dhcp_client_id, "cliend id to send to the DHCP server");
BAREBOX_MAGICVAR(dhcp_tftp_server_name, "TFTP server Name returned from DHCP request");
--
1.7.9.1
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