Initial Contribution

1 files changed, 100 insertions, 0 deletions

diff --git a/libnetutils/dhcpmsg.c b/libnetutils/dhcpmsg.c
new file mode 100644
index 0000000..1e0a233
--- /dev/null
+++ b/libnetutils/dhcpmsg.c
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2008, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <netinet/in.h>
+
+#include "dhcpmsg.h"
+
+static void *init_dhcp_msg(dhcp_msg *msg, int type, void *hwaddr, uint32_t xid)
+{
+    uint8_t *x;
+
+    memset(msg, 0, sizeof(dhcp_msg));
+
+    msg->op = OP_BOOTREQUEST;
+    msg->htype = HTYPE_ETHER;
+    msg->hlen = 6;
+    msg->hops = 0;
+
+    msg->flags = htons(FLAGS_BROADCAST);
+
+    msg->xid = xid;
+
+    memcpy(msg->chaddr, hwaddr, 6);
+
+    x = msg->options;
+
+    *x++ = OPT_COOKIE1;
+    *x++ = OPT_COOKIE2;
+    *x++ = OPT_COOKIE3;
+    *x++ = OPT_COOKIE4;
+
+    *x++ = OPT_MESSAGE_TYPE;
+    *x++ = 1;
+    *x++ = type;
+
+    return x;
+}
+
+int init_dhcp_discover_msg(dhcp_msg *msg, void *hwaddr, uint32_t xid)
+{
+    uint8_t *x;
+
+    x = init_dhcp_msg(msg, DHCPDISCOVER, hwaddr, xid);
+
+    *x++ = OPT_PARAMETER_LIST;
+    *x++ = 4;
+    *x++ = OPT_SUBNET_MASK;
+    *x++ = OPT_GATEWAY;
+    *x++ = OPT_DNS;
+    *x++ = OPT_BROADCAST_ADDR;
+
+    *x++ = OPT_END;
+
+    return DHCP_MSG_FIXED_SIZE + (x - msg->options);
+}
+
+int init_dhcp_request_msg(dhcp_msg *msg, void *hwaddr, uint32_t xid,
+                          uint32_t ipaddr, uint32_t serveraddr)
+{
+    uint8_t *x;
+
+    x = init_dhcp_msg(msg, DHCPREQUEST, hwaddr, xid);
+
+    *x++ = OPT_PARAMETER_LIST;
+    *x++ = 4;
+    *x++ = OPT_SUBNET_MASK;
+    *x++ = OPT_GATEWAY;
+    *x++ = OPT_DNS;
+    *x++ = OPT_BROADCAST_ADDR;
+
+    *x++ = OPT_REQUESTED_IP;
+    *x++ = 4;
+    memcpy(x, &ipaddr, 4);
+    x +=  4;
+
+    *x++ = OPT_SERVER_ID;
+    *x++ = 4;
+    memcpy(x, &serveraddr, 4);
+    x += 4;
+
+    *x++ = OPT_END;
+
+    return DHCP_MSG_FIXED_SIZE + (x - msg->options);
+}