[dhcp_relay] Enhance DHCP monitor application to support DHCPv6 (sonic-net#8060)

#### Why I did it

Enhance DHCP monitor application following the implementation PR: sonic-net#7772

#### How I did it

Add the support for monitoring DHCPv6 packets.

#### How to verify it

Install an image with this PR and the implementation PR.

Author: shlomibitton

src/dhcpmon/src/dhcp_device.c

@@ -18,21 +18,43 @@
 
 
 /**
- * DHCP message types
+ * DHCPv4 message types
  **/
 typedef enum
 {
-    DHCP_MESSAGE_TYPE_DISCOVER = 1,
-    DHCP_MESSAGE_TYPE_OFFER    = 2,
-    DHCP_MESSAGE_TYPE_REQUEST  = 3,
-    DHCP_MESSAGE_TYPE_DECLINE  = 4,
-    DHCP_MESSAGE_TYPE_ACK      = 5,
-    DHCP_MESSAGE_TYPE_NAK      = 6,
-    DHCP_MESSAGE_TYPE_RELEASE  = 7,
-    DHCP_MESSAGE_TYPE_INFORM   = 8,
-
-    DHCP_MESSAGE_TYPE_COUNT
-} dhcp_message_type_t;
+    DHCPv4_MESSAGE_TYPE_DISCOVER = 1,
+    DHCPv4_MESSAGE_TYPE_OFFER    = 2,
+    DHCPv4_MESSAGE_TYPE_REQUEST  = 3,
+    DHCPv4_MESSAGE_TYPE_DECLINE  = 4,
+    DHCPv4_MESSAGE_TYPE_ACK      = 5,
+    DHCPv4_MESSAGE_TYPE_NAK      = 6,
+    DHCPv4_MESSAGE_TYPE_RELEASE  = 7,
+    DHCPv4_MESSAGE_TYPE_INFORM   = 8,
+
+    DHCPv4_MESSAGE_TYPE_COUNT
+} dhcpv4_message_type_t;
+
+/**
+ * DHCPv6 message types
+ **/
+typedef enum
+{
+    DHCPv6_MESSAGE_TYPE_SOLICIT             = 1,
+    DHCPv6_MESSAGE_TYPE_ADVERTISE           = 2,
+    DHCPv6_MESSAGE_TYPE_REQUEST             = 3,
+    DHCPv6_MESSAGE_TYPE_CONFIRM             = 4,
+    DHCPv6_MESSAGE_TYPE_RENEW               = 5,
+    DHCPv6_MESSAGE_TYPE_REBIND              = 6,
+    DHCPv6_MESSAGE_TYPE_REPLY               = 7,
+    DHCPv6_MESSAGE_TYPE_RELEASE             = 8,
+    DHCPv6_MESSAGE_TYPE_DECLINE             = 9,
+    DHCPv6_MESSAGE_TYPE_RECONFIGURE         = 10,
+    DHCPv6_MESSAGE_TYPE_INFORMATION_REQUEST = 11,
+    DHCPv6_MESSAGE_TYPE_RELAY_FORWARD       = 12,
+    DHCPv6_MESSAGE_TYPE_RELAY_REPLY         = 13,
+
+    DHCPv6_MESSAGE_TYPE_COUNT
+} dhcpv6_message_type_t;
 
 /** packet direction */
 typedef enum
@@ -60,26 +82,42 @@ typedef enum
     DHCP_MON_STATUS_INDETERMINATE,  /** DHCP relay health could not be determined */
 } dhcp_mon_status_t;
 
+/** dhcp type */
+typedef enum
+{
+    DHCPv4_TYPE,
+    DHCPv6_TYPE,
+} dhcp_type_t;
+
 /** dhcp check type */
 typedef enum
 {
     DHCP_MON_CHECK_NEGATIVE,    /** Presence of relayed DHCP packets activity is flagged as unhealthy state */
     DHCP_MON_CHECK_POSITIVE,    /** Validate that received DORA packets are relayed */
 } dhcp_mon_check_t;
 
+typedef struct
+{
+    uint64_t v4counters[DHCP_COUNTERS_COUNT][DHCP_DIR_COUNT][DHCPv4_MESSAGE_TYPE_COUNT];
+                                    /** current/snapshot counters of DHCPv4 packets */
+    uint64_t v6counters[DHCP_COUNTERS_COUNT][DHCP_DIR_COUNT][DHCPv6_MESSAGE_TYPE_COUNT];
+                                    /** current/snapshot counters of DHCPv6 packets */
+} counters_t;
+
 /** DHCP device (interface) context */
 typedef struct
 {
     int sock;                       /** Raw socket associated with this device/interface */
-    in_addr_t ip;                   /** network address of this device (interface) */
+    in_addr_t ipv4;                 /** ipv4 network address of this device (interface) */
+    struct in6_addr ipv6;           /** ipv6 network address of this device (interface) */
     uint8_t mac[ETHER_ADDR_LEN];    /** hardware address of this device (interface) */
-    in_addr_t giaddr_ip;            /** Gateway IP address */
+    in_addr_t giaddr_ip;            /** Gateway IPv4 address */
+    struct in6_addr v6_vlan_ip;     /** Vlan IPv6 address */
     uint8_t is_uplink;              /** north interface? */
     char intf[IF_NAMESIZE];         /** device (interface) name */
     uint8_t *buffer;                /** buffer used to read socket data */
     size_t snaplen;                 /** snap length or buffer size */
-    uint64_t counters[DHCP_COUNTERS_COUNT][DHCP_DIR_COUNT][DHCP_MESSAGE_TYPE_COUNT];
-                                    /** current/snapshot counters of DHCP packets */
+    counters_t counters;            /** counters for DHCPv4/6 packets */
 } dhcp_device_context_t;
 
 /**
@@ -94,16 +132,28 @@ typedef struct
 int initialize_intf_mac_and_ip_addr(dhcp_device_context_t *context);
 
 /**
- * @code dhcp_device_get_ip(context, ip);
+ * @code dhcp_device_get_ipv4(context, ip);
+ *
+ * @brief Accessor method
+ *
+ * @param context       pointer to device (interface) context
+ * @param ip(out)       pointer to device IPv4
+ *
+ * @return 0 on success, otherwise for failure
+ */
+int dhcp_device_get_ipv4(dhcp_device_context_t *context, in_addr_t *ip);
+
+/**
+ * @code dhcp_device_get_ipv6(context, ip);
  *
  * @brief Accessor method
  *
  * @param context       pointer to device (interface) context
- * @param ip(out)       pointer to device IP
+ * @param ip(out)       pointer to device IPv6
  *
  * @return 0 on success, otherwise for failure
  */
-int dhcp_device_get_ip(dhcp_device_context_t *context, in_addr_t *ip);
+int dhcp_device_get_ipv6(dhcp_device_context_t *context, struct in6_addr *ip);
 
 /**
  * @code dhcp_device_get_aggregate_context();
@@ -130,21 +180,23 @@ int dhcp_device_init(dhcp_device_context_t **context,
                      uint8_t is_uplink);
 
 /**
- * @code dhcp_device_start_capture(context, snaplen, base, giaddr_ip);
+ * @code dhcp_device_start_capture(context, snaplen, base, giaddr_ip, v6_vlan_ip);
  *
  * @brief starts packet capture on this interface
  *
  * @param context           pointer to device (interface) context
  * @param snaplen           length of packet capture
  * @param base              pointer to libevent base
  * @param giaddr_ip         gateway IP address
+ * @param v6_vlan_ip        vlan IPv6 address
  *
  * @return 0 on success, otherwise for failure
  */
 int dhcp_device_start_capture(dhcp_device_context_t *context,
                               size_t snaplen,
                               struct event_base *base,
-                              in_addr_t giaddr_ip);
+                              in_addr_t giaddr_ip,
+                              struct in6_addr v6_vlan_ip);
 
 /**
  * @code dhcp_device_shutdown(context);
@@ -158,17 +210,18 @@ int dhcp_device_start_capture(dhcp_device_context_t *context,
 void dhcp_device_shutdown(dhcp_device_context_t *context);
 
 /**
- * @code dhcp_device_get_status(check_type, context);
+ * @code dhcp_device_get_status(check_type, context, type);
  *
  * @brief collects DHCP relay status info for a given interface. If context is null, it will report aggregate
  *        status
  *
  * @param check_type        Type of validation
  * @param context           Device (interface) context
+ * @param type              DHCP type
  *
  * @return DHCP_MON_STATUS_HEALTHY, DHCP_MON_STATUS_UNHEALTHY, or DHCP_MON_STATUS_INDETERMINATE
  */
-dhcp_mon_status_t dhcp_device_get_status(dhcp_mon_check_t check_type, dhcp_device_context_t *context);
+dhcp_mon_status_t dhcp_device_get_status(dhcp_mon_check_t check_type, dhcp_device_context_t *context, dhcp_type_t type);
 
 /**
  * @code dhcp_device_update_snapshot(context);
@@ -185,10 +238,21 @@ void dhcp_device_update_snapshot(dhcp_device_context_t *context);
  * @brief prints status counters to syslog. If context is null, it will print aggregate status
  *
  * @param context       Device (interface) context
- * @param counters_type Counter type to be printed
+ * @param type          Counter type to be printed
  *
  * @return none
  */
 void dhcp_device_print_status(dhcp_device_context_t *context, dhcp_counters_type_t type);
 
+/**
+ * @code dhcp_device_active_types(dhcpv4, dhcpv6);
+ *
+ * @brief update local variables with active protocols
+ *
+ * @param dhcpv4       DHCPv4 enable flag
+ * @param dhcpv6       DHCPv6 enable flag
+ *
+ * @return none
+ */
+void dhcp_device_active_types(bool dhcpv4, bool dhcpv6);
 #endif /* DHCP_DEVICE_H_ */

src/dhcpmon/src/dhcp_device.h

@@ -9,6 +9,8 @@
 #include <syslog.h>
 #include <sys/queue.h>
 #include <stdlib.h>
+#include <arpa/inet.h>
+#include <stdbool.h>
 
 #include "dhcp_devman.h"
 
@@ -35,7 +37,8 @@ static uint32_t dhcp_num_mgmt_intf = 0;
 
 /** On Device  vlan interface IP address corresponding vlan downlink IP
  *  This IP is used to filter Offer/Ack packet coming from DHCP server */
-static in_addr_t vlan_ip = 0;
+static in_addr_t v4_vlan_ip = 0;
+static struct in6_addr v6_vlan_ip = {0};
 
 /* Device loopback interface ip, which will be used as the giaddr in dual tor setup. */
 static in_addr_t loopback_ip = 0;
@@ -136,7 +139,8 @@ int dhcp_devman_add_intf(const char *name, char intf_type)
 
         rv = dhcp_device_init(&dev->dev_context, dev->name, dev->is_uplink);
         if (rv == 0 && intf_type == 'd') {
-            rv = dhcp_device_get_ip(dev->dev_context, &vlan_ip);
+            rv = dhcp_device_get_ipv4(dev->dev_context, &v4_vlan_ip);
+            rv = dhcp_device_get_ipv6(dev->dev_context, &v6_vlan_ip);
 
             dhcp_device_context_t *agg_dev = dhcp_device_get_aggregate_context();
 
@@ -174,7 +178,7 @@ int dhcp_devman_setup_dual_tor_mode(const char *name)
     }
 
     if (initialize_intf_mac_and_ip_addr(&loopback_intf_context) == 0 &&
-        dhcp_device_get_ip(&loopback_intf_context, &loopback_ip) == 0) {
+        dhcp_device_get_ipv4(&loopback_intf_context, &loopback_ip) == 0) {
             dual_tor_mode = 1;
     } else {
         syslog(LOG_ALERT, "failed to retrieve ip addr for loopback interface (%s)", name);
@@ -197,11 +201,13 @@ int dhcp_devman_start_capture(size_t snaplen, struct event_base *base)
 
     if ((dhcp_num_south_intf == 1) && (dhcp_num_north_intf >= 1)) {
         LIST_FOREACH(int_ptr, &intfs, entry) {
-            rv = dhcp_device_start_capture(int_ptr->dev_context, snaplen, base, dual_tor_mode ? loopback_ip : vlan_ip);
+            rv = dhcp_device_start_capture(int_ptr->dev_context, snaplen, base, dual_tor_mode ? loopback_ip : v4_vlan_ip, v6_vlan_ip);
             if (rv == 0) {
+                char ipv6_addr[INET6_ADDRSTRLEN];
+                inet_ntop(AF_INET6, &int_ptr->dev_context->ipv6, ipv6_addr, sizeof(ipv6_addr));
                 syslog(LOG_INFO,
-                       "Capturing DHCP packets on interface %s, ip: 0x%08x, mac [%02x:%02x:%02x:%02x:%02x:%02x] \n",
-                       int_ptr->name, int_ptr->dev_context->ip, int_ptr->dev_context->mac[0],
+                       "Capturing DHCP packets on interface %s, ipv4: 0x%08x, ipv6: %s, mac [%02x:%02x:%02x:%02x:%02x:%02x] \n",
+                       int_ptr->name, int_ptr->dev_context->ipv4, ipv6_addr, int_ptr->dev_context->mac[0],
                        int_ptr->dev_context->mac[1], int_ptr->dev_context->mac[2], int_ptr->dev_context->mac[3],
                        int_ptr->dev_context->mac[4], int_ptr->dev_context->mac[5]);
             }
@@ -219,13 +225,13 @@ int dhcp_devman_start_capture(size_t snaplen, struct event_base *base)
 }
 
 /**
- * @code dhcp_devman_get_status(check_type, context);
+ * @code dhcp_devman_get_status(check_type, context, type);
  *
  * @brief collects DHCP relay status info.
  */
-dhcp_mon_status_t dhcp_devman_get_status(dhcp_mon_check_t check_type, dhcp_device_context_t *context)
+dhcp_mon_status_t dhcp_devman_get_status(dhcp_mon_check_t check_type, dhcp_device_context_t *context, dhcp_type_t type)
 {
-    return dhcp_device_get_status(check_type, context);
+    return dhcp_device_get_status(check_type, context, type);
 }
 
 /**
@@ -267,3 +273,13 @@ void dhcp_devman_print_status(dhcp_device_context_t *context, dhcp_counters_type
         dhcp_device_print_status(context, type);
     }
 }
+
+/**
+ * @code dhcp_devman_active_types(dhcpv4, dhcpv6);
+ *
+ * @brief update local variables with active protocols
+ */
+void dhcp_devman_active_types(bool dhcpv4, bool dhcpv6)
+{
+    dhcp_device_active_types(dhcpv4, dhcpv6);
+}

src/dhcpmon/src/dhcp_devman.c

@@ -87,16 +87,17 @@ int dhcp_devman_setup_dual_tor_mode(const char *name);
 int dhcp_devman_start_capture(size_t snaplen, struct event_base *base);
 
 /**
- * @code dhcp_devman_get_status(check_type, context);
+ * @code dhcp_devman_get_status(check_type, context, type);
  *
  * @brief collects DHCP relay status info.
  *
  * @param check_type        Type of validation
  * @param context           pointer to device (interface) context
+ * @param type              DHCP type
  *
  * @return DHCP_MON_STATUS_HEALTHY, DHCP_MON_STATUS_UNHEALTHY, or DHCP_MON_STATUS_INDETERMINATE
  */
-dhcp_mon_status_t dhcp_devman_get_status(dhcp_mon_check_t check_type, dhcp_device_context_t *context);
+dhcp_mon_status_t dhcp_devman_get_status(dhcp_mon_check_t check_type, dhcp_device_context_t *context, dhcp_type_t type);
 
 /**
  * @code dhcp_devman_update_snapshot(context);
@@ -119,4 +120,16 @@ void dhcp_devman_update_snapshot(dhcp_device_context_t *context);
  */
 void dhcp_devman_print_status(dhcp_device_context_t *context, dhcp_counters_type_t type);
 
+/**
+ * @code dhcp_devman_active_types(dhcpv4, dhcpv6);
+ *
+ * @brief update local variables with active protocols
+ *
+ * @param dhcpv4       flag indicating dhcpv4 is enabled
+ * @param dhcpv6       flag indicating dhcpv6 is enabled
+ *
+ * @return none
+ */
+void dhcp_devman_active_types(bool dhcpv4, bool dhcpv6);
+
 #endif /* DHCP_DEVMAN_H_ */