DHCPD: Add support for the dhcp options for netmask, router and dns. From Brennan Ashton

2 files changed, 82 insertions, 1 deletions

diff --git a/apps/netutils/dhcpd/Kconfig b/apps/netutils/dhcpd/Kconfig
index 3f586a74b..2a38b7a00 100644
--- a/apps/netutils/dhcpd/Kconfig
+++ b/apps/netutils/dhcpd/Kconfig
@@ -61,6 +61,18 @@ config NETUTILS_DHCPD_STARTIP
 	hex "First IP address"
 	default 0x0a000002
 
+config NETUTILS_DHCPD_ROUTERIP
+	hex "Router IP (0 to disable)"
+	default 0x0a000001
+
+config NETUTILS_DHCPD_NETMASK
+	hex "Netmask (0 to disable)"
+	default 0xffffff00
+
+config NETUTILS_DHCPD_DNSIP
+	hex "DNS (0 to disable)"
+	default 0x08080808
+
 config NETUTILS_DHCPD_OFFERTIME
 	int "Offer time (seconds)"
 	default 3600
diff --git a/apps/netutils/dhcpd/dhcpd.c b/apps/netutils/dhcpd/dhcpd.c
index b0f171384..817c5d1c0 100644
--- a/apps/netutils/dhcpd/dhcpd.c
+++ b/apps/netutils/dhcpd/dhcpd.c
@@ -86,6 +86,10 @@
 /*                              Code    Data   Description                  */
 /*                                      Length                              */
 #define DHCP_OPTION_PAD           0  /*  1     Pad                          */
+#define DHCP_OPTION_SUBNET_MASK   1  /*  1     Subnet Mask                  */
+#define DHCP_OPTION_ROUTER        3  /*  4     Router                       */
+#define DHCP_OPTION_DNS_SERVER    6  /*  4N    DNS                          */
+#define DHCP_OPTION_DNS_SERVER_L  4  /*        DNS Length                   */
 #define DHCP_OPTION_REQ_IPADDR   50  /*  4     Requested IP Address         */
 #define DHCP_OPTION_LEASE_TIME   51  /*  4     IP address lease time        */
 #define DHCP_OPTION_OVERLOAD     52  /*  1     Option overload              */
@@ -181,6 +185,21 @@
 #  define CONFIG_NETUTILS_DHCPD_DECLINETIME (60*60) /* 1 hour */
 #endif
 
+#undef HAVE_ROUTERIP
+#if defined(CONFIG_NETUTILS_DHCPD_ROUTERIP) && CONFIG_NETUTILS_DHCPD_ROUTERIP
+#  define HAVE_ROUTERIP 1
+#endif
+
+#undef HAVE_NETMASK
+#if defined(CONFIG_NETUTILS_DHCPD_NETMASK) && CONFIG_NETUTILS_DHCPD_NETMASK
+#  define HAVE_NETMASK 1
+#endif
+
+#undef HAVE_DNSIP
+#if defined(CONFIG_NETUTILS_DHCPD_DNSIP) && CONFIG_NETUTILS_DHCPD_DNSIP
+#  define HAVE_DNSIP 1
+#endif
+
 #undef HAVE_LEASE_TIME
 #if defined(CONFIG_NETUTILS_DHCPD_HOST) || !defined(CONFIG_DISABLE_POSIX_TIMERS)
 #  define HAVE_LEASE_TIME 1
@@ -737,6 +756,31 @@ static int dhcpd_addoption32(uint8_t code, uint32_t value)
 }
 
 /****************************************************************************
+ * Name: dhcpd_addoption_n
+ ****************************************************************************/
+
+#if HAVE_DNSIP
+static int dhcpd_addoption_n(uint8_t code, uint8_t *value, uint8_t len)
+{
+  /* REVISIT: This form may not be supported by older compilers.  It may
+   * need to be replaced with malloc() and free() for portability.
+   */
+
+  uint8_t option[len+2];
+
+  /* Construct the option sequence */
+
+  option[DHCPD_OPTION_CODE]   = code;
+  option[DHCPD_OPTION_LENGTH] = len;
+  memcpy(&option[DHCPD_OPTION_DATA], value, len);
+
+  /* Add the option sequence to the response */
+
+  return dhcpd_addoption(option);
+}
+#endif
+
+/****************************************************************************
  * Name: dhcpd_soclet
  ****************************************************************************/
 
@@ -953,7 +997,10 @@ static int dhcpd_sendpacket(int bbroadcast)
 static inline int dhcpd_sendoffer(in_addr_t ipaddr, uint32_t leasetime)
 {
   in_addr_t netaddr;
-
+#if HAVE_DNSIP
+  uint32_t dnsaddr;
+  dnsaddr = htonl(CONFIG_NETUTILS_DHCPD_DNSIP);
+#endif
   /* IP address is in host order */
 
   nvdbg("Sending offer: %08lx\n", (long)ipaddr);
@@ -970,6 +1017,15 @@ static inline int dhcpd_sendoffer(in_addr_t ipaddr, uint32_t leasetime)
   /* Add the leasetime to the response options */
 
   dhcpd_addoption32(DHCP_OPTION_LEASE_TIME, htonl(leasetime));
+#if HAVE_NETMASK
+  dhcpd_addoption32(DHCP_OPTION_SUBNET_MASK, htonl(CONFIG_NETUTILS_DHCPD_NETMASK));
+#endif
+#if HAVE_ROUTERIP
+  dhcpd_addoption32(DHCP_OPTION_ROUTER, htonl(CONFIG_NETUTILS_DHCPD_ROUTERIP));
+#endif
+#if HAVE_DNSIP
+  dhcpd_addoption_n(DHCP_OPTION_DNS_SERVER, (uint8_t*)&dnsaddr, DHCP_OPTION_DNS_SERVER_L);
+#endif
 
   /* Send the offer response */
 
@@ -1001,6 +1057,10 @@ int dhcpd_sendack(in_addr_t ipaddr)
 {
   uint32_t leasetime = CONFIG_NETUTILS_DHCPD_LEASETIME;
   in_addr_t netaddr;
+#if HAVE_DNSIP
+  uint32_t dnsaddr;
+  dnsaddr = htonl(CONFIG_NETUTILS_DHCPD_DNSIP);
+#endif
 
   /* Initialize the ACK response */
 
@@ -1019,6 +1079,15 @@ int dhcpd_sendack(in_addr_t ipaddr)
   /* Add the lease time to the response */
 
   dhcpd_addoption32(DHCP_OPTION_LEASE_TIME, htonl(leasetime));
+#if HAVE_NETMASK
+  dhcpd_addoption32(DHCP_OPTION_SUBNET_MASK, htonl(CONFIG_NETUTILS_DHCPD_NETMASK));
+#endif
+#if HAVE_ROUTERIP
+  dhcpd_addoption32(DHCP_OPTION_ROUTER, htonl(CONFIG_NETUTILS_DHCPD_ROUTERIP));
+#endif
+#if HAVE_DNSIP
+  dhcpd_addoption_n(DHCP_OPTION_DNS_SERVER, (uint8_t*)&dnsaddr, DHCP_OPTION_DNS_SERVER_L);
+#endif
 
 #ifdef CONFIG_NETUTILS_DHCPD_IGNOREBROADCAST
   if (dhcpd_sendpacket(true) < 0)