From 2ba5615887f1409cc1369cc9d7041d169ef75978 Mon Sep 17 00:00:00 2001 From: shlomibitton <60430976+shlomibitton@users.noreply.github.com> Date: Mon, 26 Jul 2021 18:41:20 +0300 Subject: [PATCH] [dhcp_relay] Enhance DHCP monitor application to support DHCPv6 (#8060) #### Why I did it Enhance DHCP monitor application following the implementation PR: https://github.com/Azure/sonic-buildimage/pull/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. --- src/dhcp_device.c | 564 +++++++++++++++++++++++++++++++++++----------- src/dhcp_device.h | 112 +++++++-- src/dhcp_devman.c | 34 ++- src/dhcp_devman.h | 17 +- src/dhcp_mon.c | 106 +++++++-- src/dhcp_mon.h | 4 +- src/main.c | 20 +- 7 files changed, 674 insertions(+), 183 deletions(-) diff --git a/src/dhcp_device.c b/src/dhcp_device.c index f45483f85..3078295e4 100644 --- a/src/dhcp_device.c +++ b/src/dhcp_device.c @@ -21,25 +21,51 @@ #include #include #include +#include +#include +#include #include "dhcp_device.h" +/** DHCP versions flags */ +static bool dhcpv4_enabled; +static bool dhcpv6_enabled; + /** Counter print width */ #define DHCP_COUNTER_WIDTH 9 /** Start of Ether header of a captured frame */ #define ETHER_START_OFFSET 0 +/** EtherType field offset from Ether header of a captured frame */ +#define ETHER_TYPE_OFFSET (ETHER_START_OFFSET + 12) /** Start of IP header of a captured frame */ #define IP_START_OFFSET (ETHER_START_OFFSET + ETHER_HDR_LEN) -/** Start of UDP header of a captured frame */ -#define UDP_START_OFFSET (IP_START_OFFSET + sizeof(struct ip)) -/** Start of DHCP header of a captured frame */ -#define DHCP_START_OFFSET (UDP_START_OFFSET + sizeof(struct udphdr)) -/** Start of DHCP Options segment of a captured frame */ -#define DHCP_OPTIONS_HEADER_SIZE 240 +/** Start of UDP header on IPv4 packet of a captured frame */ +#define UDPv4_START_OFFSET (IP_START_OFFSET + sizeof(struct ip)) +/** Start of DHCPv4 header of a captured frame */ +#define DHCPv4_START_OFFSET (UDPv4_START_OFFSET + sizeof(struct udphdr)) +/** Start of DHCPv4 Options segment of a captured frame */ +#define DHCPv4_OPTIONS_HEADER_SIZE 240 /** Offset of DHCP GIADDR */ #define DHCP_GIADDR_OFFSET 24 +/** IPv6 link-local prefix */ +#define IPV6_LINK_LOCAL_PREFIX 0x80fe +/** Start of UDP header on IPv6 packet of a captured frame */ +#define UDPv6_START_OFFSET (IP_START_OFFSET + sizeof(struct ip6_hdr)) +/** Start of DHCPv6 header of a captured frame */ +#define DHCPv6_START_OFFSET (UDPv6_START_OFFSET + sizeof(struct udphdr)) +/** Size of 'type' field on DHCPv6 header */ +#define DHCPv6_TYPE_LENGTH 1 +/** Size of DHCPv6 relay message header to first option */ +#define DHCPv6_RELAY_MSG_OPTIONS_OFFSET 34 +/** Size of 'option' field on DHCPv6 header */ +#define DHCPv6_OPTION_LENGTH 2 +/** Size of 'option length' field on DHCPv6 header */ +#define DHCPv6_OPTION_LEN_LENGTH 2 +/** DHCPv6 OPTION_RELAY_MSG */ +#define DHCPv6_OPTION_RELAY_MSG 9 + #define OP_LDHA (BPF_LD | BPF_H | BPF_ABS) /** bpf ldh Abs */ #define OP_LDHI (BPF_LD | BPF_H | BPF_IND) /** bpf ldh Ind */ #define OP_LDB (BPF_LD | BPF_B | BPF_ABS) /** bpf ldb Abs*/ @@ -49,34 +75,40 @@ #define OP_JSET (BPF_JMP | BPF_JSET | BPF_K) /** bpf jset */ #define OP_LDXB (BPF_LDX | BPF_B | BPF_MSH) /** bpf ldxb */ -/** Berkeley Packet Filter program for "udp and (port 67 or port 68)". +/** Berkeley Packet Filter program for "udp and (port 546 or port 547 or port 67 or port 68)". * This program is obtained using the following command tcpdump: - * `tcpdump -dd "udp and (port 67 or port 68)"` + * `tcpdump -dd "udp and (port 546 or port 547 or port 67 or port 68)"` */ static struct sock_filter dhcp_bpf_code[] = { - {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x0000000c}, // (000) ldh [12] - {.code = OP_JEQ, .jt = 0, .jf = 7, .k = 0x000086dd}, // (001) jeq #0x86dd jt 2 jf 9 - {.code = OP_LDB, .jt = 0, .jf = 0, .k = 0x00000014}, // (002) ldb [20] - {.code = OP_JEQ, .jt = 0, .jf = 18, .k = 0x00000011}, // (003) jeq #0x11 jt 4 jf 22 - {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x00000036}, // (004) ldh [54] - {.code = OP_JEQ, .jt = 15, .jf = 0, .k = 0x00000043}, // (005) jeq #0x43 jt 21 jf 6 - {.code = OP_JEQ, .jt = 14, .jf = 0, .k = 0x00000044}, // (006) jeq #0x44 jt 21 jf 7 - {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x00000038}, // (007) ldh [56] - {.code = OP_JEQ, .jt = 12, .jf = 11, .k = 0x00000043}, // (008) jeq #0x43 jt 21 jf 20 - {.code = OP_JEQ, .jt = 0, .jf = 12, .k = 0x00000800}, // (009) jeq #0x800 jt 10 jf 22 - {.code = OP_LDB, .jt = 0, .jf = 0, .k = 0x00000017}, // (010) ldb [23] - {.code = OP_JEQ, .jt = 0, .jf = 10, .k = 0x00000011}, // (011) jeq #0x11 jt 12 jf 22 - {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x00000014}, // (012) ldh [20] - {.code = OP_JSET, .jt = 8, .jf = 0, .k = 0x00001fff}, // (013) jset #0x1fff jt 22 jf 14 - {.code = OP_LDXB, .jt = 0, .jf = 0, .k = 0x0000000e}, // (014) ldxb 4*([14]&0xf) - {.code = OP_LDHI, .jt = 0, .jf = 0, .k = 0x0000000e}, // (015) ldh [x + 14] - {.code = OP_JEQ, .jt = 4, .jf = 0, .k = 0x00000043}, // (016) jeq #0x43 jt 21 jf 17 - {.code = OP_JEQ, .jt = 3, .jf = 0, .k = 0x00000044}, // (017) jeq #0x44 jt 21 jf 18 - {.code = OP_LDHI, .jt = 0, .jf = 0, .k = 0x00000010}, // (018) ldh [x + 16] - {.code = OP_JEQ, .jt = 1, .jf = 0, .k = 0x00000043}, // (019) jeq #0x43 jt 21 jf 20 - {.code = OP_JEQ, .jt = 0, .jf = 1, .k = 0x00000044}, // (020) jeq #0x44 jt 21 jf 22 - {.code = OP_RET, .jt = 0, .jf = 0, .k = 0x00040000}, // (021) ret #262144 - {.code = OP_RET, .jt = 0, .jf = 0, .k = 0x00000000}, // (022) ret #0 + {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x0000000c}, // (000) ldh [12] + {.code = OP_JEQ, .jt = 0, .jf = 9, .k = 0x000086dd}, // (001) jeq #0x86dd jt 2 jf 11 + {.code = OP_LDB, .jt = 0, .jf = 0, .k = 0x00000014}, // (002) ldb [20] + {.code = OP_JEQ, .jt = 0, .jf = 24, .k = 0x00000011}, // (003) jeq #0x11 jt 4 jf 28 + {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x00000036}, // (004) ldh [54] + {.code = OP_JEQ, .jt = 21, .jf = 0, .k = 0x00000222}, // (005) jeq #0x222 jt 27 jf 6 + {.code = OP_JEQ, .jt = 20, .jf = 0, .k = 0x00000223}, // (006) jeq #0x223 jt 27 jf 7 + {.code = OP_JEQ, .jt = 19, .jf = 0, .k = 0x00000043}, // (007) jeq #0x43 jt 27 jf 8 + {.code = OP_JEQ, .jt = 18, .jf = 0, .k = 0x00000044}, // (008) jeq #0x44 jt 27 jf 9 + {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x00000038}, // (009) ldh [56] + {.code = OP_JEQ, .jt = 16, .jf = 13, .k = 0x00000222}, // (010) jeq #0x222 jt 27 jf 24 + {.code = OP_JEQ, .jt = 0, .jf = 16, .k = 0x00000800}, // (011) jeq #0x800 jt 12 jf 28 + {.code = OP_LDB, .jt = 0, .jf = 0, .k = 0x00000017}, // (012) ldb [23] + {.code = OP_JEQ, .jt = 0, .jf = 14, .k = 0x00000011}, // (013) jeq #0x11 jt 14 jf 28 + {.code = OP_LDHA, .jt = 0, .jf = 0, .k = 0x00000014}, // (014) ldh [20] + {.code = OP_JSET, .jt = 12, .jf = 0, .k = 0x00001fff}, // (015) jset #0x1fff jt 28 jf 16 + {.code = OP_LDXB, .jt = 0, .jf = 0, .k = 0x0000000e}, // (016) ldxb 4*([14]&0xf) + {.code = OP_LDHI, .jt = 0, .jf = 0, .k = 0x0000000e}, // (017) ldh [x + 14] + {.code = OP_JEQ, .jt = 8, .jf = 0, .k = 0x00000222}, // (018) jeq #0x222 jt 27 jf 19 + {.code = OP_JEQ, .jt = 7, .jf = 0, .k = 0x00000223}, // (019) jeq #0x223 jt 27 jf 20 + {.code = OP_JEQ, .jt = 6, .jf = 0, .k = 0x00000043}, // (020) jeq #0x43 jt 27 jf 21 + {.code = OP_JEQ, .jt = 5, .jf = 0, .k = 0x00000044}, // (021) jeq #0x44 jt 27 jf 22 + {.code = OP_LDHI, .jt = 0, .jf = 0, .k = 0x00000010}, // (022) ldh [x + 16] + {.code = OP_JEQ, .jt = 3, .jf = 0, .k = 0x00000222}, // (023) jeq #0x222 jt 27 jf 24 + {.code = OP_JEQ, .jt = 2, .jf = 0, .k = 0x00000223}, // (024) jeq #0x223 jt 27 jf 25 + {.code = OP_JEQ, .jt = 1, .jf = 0, .k = 0x00000043}, // (025) jeq #0x43 jt 27 jf 26 + {.code = OP_JEQ, .jt = 0, .jf = 1, .k = 0x00000044}, // (026) jeq #0x44 jt 27 jf 28 + {.code = OP_RET, .jt = 0, .jf = 0, .k = 0x00040000}, // (027) ret #262144 + {.code = OP_RET, .jt = 0, .jf = 0, .k = 0x00000000}, // (028) ret }; /** Filter program socket struct */ @@ -89,16 +121,27 @@ static struct sock_fprog dhcp_sock_bfp = { */ static dhcp_device_context_t aggregate_dev = {0}; -/** Monitored DHCP message type */ -static dhcp_message_type_t monitored_msgs[] = { - DHCP_MESSAGE_TYPE_DISCOVER, - DHCP_MESSAGE_TYPE_OFFER, - DHCP_MESSAGE_TYPE_REQUEST, - DHCP_MESSAGE_TYPE_ACK +/** Monitored DHCPv4 message type */ +static dhcpv4_message_type_t v4_monitored_msgs[] = { + DHCPv4_MESSAGE_TYPE_DISCOVER, + DHCPv4_MESSAGE_TYPE_OFFER, + DHCPv4_MESSAGE_TYPE_REQUEST, + DHCPv4_MESSAGE_TYPE_ACK +}; + +/** Monitored DHCPv6 message type */ +static dhcpv6_message_type_t v6_monitored_msgs[] = { + DHCPv6_MESSAGE_TYPE_SOLICIT, + DHCPv6_MESSAGE_TYPE_ADVERTISE, + DHCPv6_MESSAGE_TYPE_REQUEST, + DHCPv6_MESSAGE_TYPE_REPLY }; -/** Number of monitored DHCP message type */ -static uint8_t monitored_msg_sz = sizeof(monitored_msgs) / sizeof(*monitored_msgs); +/** Number of monitored DHCPv4 message type */ +static uint8_t v4_monitored_msg_sz = sizeof(v4_monitored_msgs) / sizeof(*v4_monitored_msgs); + +/** Number of monitored DHCPv6 message type */ +static uint8_t v6_monitored_msg_sz = sizeof(v6_monitored_msgs) / sizeof(*v6_monitored_msgs); /** * @code handle_dhcp_option_53(context, dhcp_option, dir, iphdr, dhcphdr); @@ -123,27 +166,27 @@ static void handle_dhcp_option_53(dhcp_device_context_t *context, switch (dhcp_option[2]) { // DHCP messages send by client - case DHCP_MESSAGE_TYPE_DISCOVER: - case DHCP_MESSAGE_TYPE_REQUEST: - case DHCP_MESSAGE_TYPE_DECLINE: - case DHCP_MESSAGE_TYPE_RELEASE: - case DHCP_MESSAGE_TYPE_INFORM: + case DHCPv4_MESSAGE_TYPE_DISCOVER: + case DHCPv4_MESSAGE_TYPE_REQUEST: + case DHCPv4_MESSAGE_TYPE_DECLINE: + case DHCPv4_MESSAGE_TYPE_RELEASE: + case DHCPv4_MESSAGE_TYPE_INFORM: giaddr = ntohl(dhcphdr[DHCP_GIADDR_OFFSET] << 24 | dhcphdr[DHCP_GIADDR_OFFSET + 1] << 16 | dhcphdr[DHCP_GIADDR_OFFSET + 2] << 8 | dhcphdr[DHCP_GIADDR_OFFSET + 3]); if ((context->giaddr_ip == giaddr && context->is_uplink && dir == DHCP_TX) || (!context->is_uplink && dir == DHCP_RX && iphdr->ip_dst.s_addr == INADDR_BROADCAST)) { - context->counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; - aggregate_dev.counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; + context->counters.v4counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; + aggregate_dev.counters.v4counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; } break; // DHCP messages send by server - case DHCP_MESSAGE_TYPE_OFFER: - case DHCP_MESSAGE_TYPE_ACK: - case DHCP_MESSAGE_TYPE_NAK: + case DHCPv4_MESSAGE_TYPE_OFFER: + case DHCPv4_MESSAGE_TYPE_ACK: + case DHCPv4_MESSAGE_TYPE_NAK: if ((context->giaddr_ip == iphdr->ip_dst.s_addr && context->is_uplink && dir == DHCP_RX) || (!context->is_uplink && dir == DHCP_TX)) { - context->counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; - aggregate_dev.counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; + context->counters.v4counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; + aggregate_dev.counters.v4counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option[2]]++; } break; default: @@ -152,6 +195,43 @@ static void handle_dhcp_option_53(dhcp_device_context_t *context, } } +/** + * @code handle_dhcpv6_option(context, dhcp_option, dir); + * + * @brief handle the logic related to DHCPv6 option + * + * @param context Device (interface) context + * @param dhcp_option pointer to DHCP option buffer space + * @param dir packet direction + * + * @return none + */ +static void handle_dhcpv6_option(dhcp_device_context_t *context, + const u_char dhcp_option, + dhcp_packet_direction_t dir) +{ + switch (dhcp_option) + { + case DHCPv6_MESSAGE_TYPE_SOLICIT: + case DHCPv6_MESSAGE_TYPE_REQUEST: + case DHCPv6_MESSAGE_TYPE_CONFIRM: + case DHCPv6_MESSAGE_TYPE_RENEW: + case DHCPv6_MESSAGE_TYPE_REBIND: + case DHCPv6_MESSAGE_TYPE_RELEASE: + case DHCPv6_MESSAGE_TYPE_DECLINE: + case DHCPv6_MESSAGE_TYPE_ADVERTISE: + case DHCPv6_MESSAGE_TYPE_REPLY: + case DHCPv6_MESSAGE_TYPE_RECONFIGURE: + case DHCPv6_MESSAGE_TYPE_INFORMATION_REQUEST: + context->counters.v6counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option]++; + aggregate_dev.counters.v6counters[DHCP_COUNTERS_CURRENT][dir][dhcp_option]++; + break; + default: + syslog(LOG_WARNING, "handle_dhcpv6_option(%s): Unknown DHCPv6 option type %d", context->intf, dhcp_option); + break; + } +} + /** * @code read_callback(fd, event, arg); * @@ -171,16 +251,29 @@ static void read_callback(int fd, short event, void *arg) while ((event == EV_READ) && ((buffer_sz = recv(fd, context->buffer, context->snaplen, MSG_DONTWAIT)) > 0)) { struct ether_header *ethhdr = (struct ether_header*) context->buffer; - struct ip *iphdr = (struct ip*) (context->buffer + IP_START_OFFSET); - struct udphdr *udp = (struct udphdr*) (context->buffer + UDP_START_OFFSET); - uint8_t *dhcphdr = context->buffer + DHCP_START_OFFSET; - int dhcp_option_offset = DHCP_START_OFFSET + DHCP_OPTIONS_HEADER_SIZE; - - if ((buffer_sz > UDP_START_OFFSET + sizeof(struct udphdr) + DHCP_OPTIONS_HEADER_SIZE) && - (ntohs(udp->len) > DHCP_OPTIONS_HEADER_SIZE)) { - int dhcp_sz = ntohs(udp->len) < buffer_sz - UDP_START_OFFSET - sizeof(struct udphdr) ? - ntohs(udp->len) : buffer_sz - UDP_START_OFFSET - sizeof(struct udphdr); - int dhcp_option_sz = dhcp_sz - DHCP_OPTIONS_HEADER_SIZE; + struct ip *iphdr; + struct ip6_hdr *ipv6hdr; + struct udphdr *udp; + uint8_t *dhcphdr; + int dhcp_option_offset; + + bool is_ipv4 = (ntohs(ethhdr->ether_type) == ETHERTYPE_IP); + if (is_ipv4) { + iphdr = (struct ip*) (context->buffer + IP_START_OFFSET); + udp = (struct udphdr*) (context->buffer + UDPv4_START_OFFSET); + dhcphdr = context->buffer + DHCPv4_START_OFFSET; + dhcp_option_offset = DHCPv4_START_OFFSET + DHCPv4_OPTIONS_HEADER_SIZE; + } else { + ipv6hdr = (struct ip6_hdr*) (context->buffer + IP_START_OFFSET); + udp = (struct udphdr*) (context->buffer + UDPv6_START_OFFSET); + dhcphdr = context->buffer + DHCPv6_START_OFFSET; + dhcp_option_offset = DHCPv6_START_OFFSET; + } + if (is_ipv4 && dhcpv4_enabled && (buffer_sz > UDPv4_START_OFFSET + sizeof(struct udphdr) + DHCPv4_OPTIONS_HEADER_SIZE) && + (ntohs(udp->len) > DHCPv4_OPTIONS_HEADER_SIZE)) { + int dhcp_sz = ntohs(udp->len) < buffer_sz - UDPv4_START_OFFSET - sizeof(struct udphdr) ? + ntohs(udp->len) : buffer_sz - UDPv4_START_OFFSET - sizeof(struct udphdr); + int dhcp_option_sz = dhcp_sz - DHCPv4_OPTIONS_HEADER_SIZE; const u_char *dhcp_option = context->buffer + dhcp_option_offset; dhcp_packet_direction_t dir = (ethhdr->ether_shost[0] == context->mac[0] && ethhdr->ether_shost[1] == context->mac[1] && @@ -214,6 +307,35 @@ static void read_callback(int fd, short event, void *arg) offset += dhcp_option[offset + 1] + 2; } } + } + else if (!is_ipv4 && dhcpv6_enabled && (buffer_sz > UDPv6_START_OFFSET + sizeof(struct udphdr) + DHCPv6_TYPE_LENGTH)) { + const u_char* dhcp_option = context->buffer + dhcp_option_offset; + dhcp_packet_direction_t dir = (ethhdr->ether_shost[0] == context->mac[0] && + ethhdr->ether_shost[1] == context->mac[1] && + ethhdr->ether_shost[2] == context->mac[2] && + ethhdr->ether_shost[3] == context->mac[3] && + ethhdr->ether_shost[4] == context->mac[4] && + ethhdr->ether_shost[5] == context->mac[5]) ? + DHCP_TX : DHCP_RX; + int offset = 0; + uint16_t option = 0; + // Get to inner DHCP header from encapsulated RELAY_FORWARD or RELAY_REPLY header + while (dhcp_option[offset] == DHCPv6_MESSAGE_TYPE_RELAY_FORWARD || dhcp_option[offset] == DHCPv6_MESSAGE_TYPE_RELAY_REPLY) + { + // Get to DHCPv6_OPTION_RELAY_MSG from all options + offset += DHCPv6_RELAY_MSG_OPTIONS_OFFSET; + option = htons(*((uint16_t*)(&(dhcp_option[offset])))); + + while (option != DHCPv6_OPTION_RELAY_MSG) + { + offset += DHCPv6_OPTION_LENGTH; + // Add to offset the option length and get the next option ID + offset += htons(*((uint16_t*)(&(dhcp_option[offset])))); + option = htons(*((uint16_t*)(&(dhcp_option[offset])))); + } + offset += DHCPv6_OPTION_LENGTH + DHCPv6_OPTION_LEN_LENGTH; + } + handle_dhcpv6_option(context, dhcp_option[offset], dir); } else { syslog(LOG_WARNING, "read_callback(%s): read length (%ld) is too small to capture DHCP options", context->intf, buffer_sz); @@ -222,29 +344,54 @@ static void read_callback(int fd, short event, void *arg) } /** - * @code dhcp_device_is_dhcp_inactive(counters); + * @code dhcp_device_is_dhcp_inactive(v4counters, v6counters, type); * * @brief Check if there were no DHCP activity * - * @param counters current/snapshot counter + * @param v4counters current/snapshot v4counter + * + * @param v6counters current/snapshot v6counter + * + * @param type DHCP type * * @return true if there were no DHCP activity, false otherwise */ -static bool dhcp_device_is_dhcp_inactive(uint64_t counters[][DHCP_DIR_COUNT][DHCP_MESSAGE_TYPE_COUNT]) +static bool dhcp_device_is_dhcp_inactive(uint64_t v4counters[][DHCP_DIR_COUNT][DHCPv4_MESSAGE_TYPE_COUNT], + uint64_t v6counters[][DHCP_DIR_COUNT][DHCPv6_MESSAGE_TYPE_COUNT], + dhcp_type_t type) { - uint64_t *rx_counters = counters[DHCP_COUNTERS_CURRENT][DHCP_RX]; - uint64_t *rx_counter_snapshot = counters[DHCP_COUNTERS_SNAPSHOT][DHCP_RX]; - bool rv = true; - for (uint8_t i = 0; (i < monitored_msg_sz) && rv; i++) { - rv = rx_counters[monitored_msgs[i]] == rx_counter_snapshot[monitored_msgs[i]]; + uint64_t *rx_counters; + uint64_t *rx_counter_snapshot; + + switch (type) + { + case DHCPv4_TYPE: + rx_counters = v4counters[DHCP_COUNTERS_CURRENT][DHCP_RX]; + rx_counter_snapshot = v4counters[DHCP_COUNTERS_SNAPSHOT][DHCP_RX]; + for (uint8_t i = 0; (i < v4_monitored_msg_sz) && rv; i++) { + rv = rx_counters[v4_monitored_msgs[i]] == rx_counter_snapshot[v4_monitored_msgs[i]]; + } + break; + + case DHCPv6_TYPE: + rx_counters = v6counters[DHCP_COUNTERS_CURRENT][DHCP_RX]; + rx_counter_snapshot = v6counters[DHCP_COUNTERS_SNAPSHOT][DHCP_RX]; + for (uint8_t i = 0; (i < v6_monitored_msg_sz) && rv; i++) { + rv = rx_counters[v6_monitored_msgs[i]] == rx_counter_snapshot[v6_monitored_msgs[i]]; + } + break; + + default: + syslog(LOG_ERR, "Unknown DHCP type %d\n", type); + break; } return rv; } /** - * @code dhcp_device_is_dhcp_msg_unhealthy(type, counters); + * @code dhcp_device_is_dhcpv4_msg_unhealthy(type, counters); * * @brief Check if DHCP relay is functioning properly for message of type 'type'. * For every rx of message 'type', there should be increment of the same message type. @@ -254,34 +401,76 @@ static bool dhcp_device_is_dhcp_inactive(uint64_t counters[][DHCP_DIR_COUNT][DHC * * @return true if DHCP message 'type' is transmitted,false otherwise */ -static bool dhcp_device_is_dhcp_msg_unhealthy(dhcp_message_type_t type, - uint64_t counters[][DHCP_DIR_COUNT][DHCP_MESSAGE_TYPE_COUNT]) +static bool dhcp_device_is_dhcpv4_msg_unhealthy(dhcpv4_message_type_t type, + uint64_t v4counters[][DHCP_DIR_COUNT][DHCPv4_MESSAGE_TYPE_COUNT]) { // check if DHCP message 'type' is being relayed - return ((counters[DHCP_COUNTERS_CURRENT][DHCP_RX][type] > counters[DHCP_COUNTERS_SNAPSHOT][DHCP_RX][type]) && - (counters[DHCP_COUNTERS_CURRENT][DHCP_TX][type] <= counters[DHCP_COUNTERS_SNAPSHOT][DHCP_TX][type]) ); + return ((v4counters[DHCP_COUNTERS_CURRENT][DHCP_RX][type] > v4counters[DHCP_COUNTERS_SNAPSHOT][DHCP_RX][type]) && + (v4counters[DHCP_COUNTERS_CURRENT][DHCP_TX][type] <= v4counters[DHCP_COUNTERS_SNAPSHOT][DHCP_TX][type]) ); } /** - * @code dhcp_device_check_positive_health(counters, counters_snapshot); + * @code dhcp_device_is_dhcpv6_msg_unhealthy(type, counters); * - * @brief Check if DHCP relay is functioning properly for monitored messages (Discover, Offer, Request, ACK.) - * For every rx of monitored messages, there should be increment of the same message type. + * @brief Check if DHCP relay is functioning properly for message of type 'type'. + * For every rx of message 'type', there should be increment of the same message type. * + * @param type DHCP message type * @param counters current/snapshot counter * + * @return true if DHCP message 'type' is transmitted,false otherwise + */ +static bool dhcp_device_is_dhcpv6_msg_unhealthy(dhcpv6_message_type_t type, + uint64_t v6counters[][DHCP_DIR_COUNT][DHCPv6_MESSAGE_TYPE_COUNT]) +{ + // check if DHCP message 'type' is being relayed + return ((v6counters[DHCP_COUNTERS_CURRENT][DHCP_RX][type] > v6counters[DHCP_COUNTERS_SNAPSHOT][DHCP_RX][type]) && + (v6counters[DHCP_COUNTERS_CURRENT][DHCP_TX][type] <= v6counters[DHCP_COUNTERS_SNAPSHOT][DHCP_TX][type]) ); +} + +/** + * @code dhcp_device_check_positive_health(v4counters, v6counters, type); + * + * @brief Check if DHCPv4/6 relay is functioning properly for monitored messages. + * DHCPv4 (Discover, Offer, Request, ACK.) and DHCPv6 (Solicit, Advertise, Request, Reply). + * For every rx of monitored messages, there should be increment of the same message type. + * + * @param v4counters current/snapshot counter + * + * @param v6counters current/snapshot counter + * + * @param type DHCP type + * * @return DHCP_MON_STATUS_HEALTHY, DHCP_MON_STATUS_UNHEALTHY, or DHCP_MON_STATUS_INDETERMINATE */ -static dhcp_mon_status_t dhcp_device_check_positive_health(uint64_t counters[][DHCP_DIR_COUNT][DHCP_MESSAGE_TYPE_COUNT]) +static dhcp_mon_status_t dhcp_device_check_positive_health(uint64_t v4counters[][DHCP_DIR_COUNT][DHCPv4_MESSAGE_TYPE_COUNT], + uint64_t v6counters[][DHCP_DIR_COUNT][DHCPv6_MESSAGE_TYPE_COUNT], + dhcp_type_t type) { dhcp_mon_status_t rv = DHCP_MON_STATUS_HEALTHY; bool is_dhcp_unhealthy = false; - for (uint8_t i = 0; (i < monitored_msg_sz) && !is_dhcp_unhealthy; i++) { - is_dhcp_unhealthy = dhcp_device_is_dhcp_msg_unhealthy(monitored_msgs[i], counters); + + switch (type) + { + case DHCPv4_TYPE: + for (uint8_t i = 0; (i < v4_monitored_msg_sz) && !is_dhcp_unhealthy; i++) { + is_dhcp_unhealthy = dhcp_device_is_dhcpv4_msg_unhealthy(v4_monitored_msgs[i], v4counters); + } + break; + + case DHCPv6_TYPE: + for (uint8_t i = 0; (i < v6_monitored_msg_sz) && !is_dhcp_unhealthy; i++) { + is_dhcp_unhealthy = dhcp_device_is_dhcpv6_msg_unhealthy(v6_monitored_msgs[i], v6counters); + } + break; + + default: + syslog(LOG_ERR, "Unknown DHCP type %d\n", type); + break; } - // if we have rx DORA then we should have corresponding tx DORA (DORA being relayed) + // if we have rx DORA/SARR then we should have corresponding tx DORA/SARR (DORA/SARR being relayed) if (is_dhcp_unhealthy) { rv = DHCP_MON_STATUS_UNHEALTHY; } @@ -290,27 +479,47 @@ static dhcp_mon_status_t dhcp_device_check_positive_health(uint64_t counters[][D } /** - * @code dhcp_device_check_negative_health(counters); + * @code dhcp_device_check_negative_health(v4counters, v6counters, type); * * @brief Check that DHCP relayed messages are not being transmitted out of this interface/dev * using its counters. The interface is negatively healthy if there are not DHCP message * travelling through it. * - * @param counters recent interface counter - * @param counters_snapshot snapshot counters + * @param v4counters current/snapshot counter + * @param v6counters current/snapshot counter + * @param type DHCP type * * @return DHCP_MON_STATUS_HEALTHY, DHCP_MON_STATUS_UNHEALTHY, or DHCP_MON_STATUS_INDETERMINATE */ -static dhcp_mon_status_t dhcp_device_check_negative_health(uint64_t counters[][DHCP_DIR_COUNT][DHCP_MESSAGE_TYPE_COUNT]) +static dhcp_mon_status_t dhcp_device_check_negative_health(uint64_t v4counters[][DHCP_DIR_COUNT][DHCPv4_MESSAGE_TYPE_COUNT], + uint64_t v6counters[][DHCP_DIR_COUNT][DHCPv6_MESSAGE_TYPE_COUNT], + dhcp_type_t type) { dhcp_mon_status_t rv = DHCP_MON_STATUS_HEALTHY; + bool is_dhcp_unhealthy = false; - uint64_t *tx_counters = counters[DHCP_COUNTERS_CURRENT][DHCP_TX]; - uint64_t *tx_counter_snapshot = counters[DHCP_COUNTERS_SNAPSHOT][DHCP_TX]; + uint64_t *tx_counters; + uint64_t *tx_counter_snapshot; - bool is_dhcp_unhealthy = false; - for (uint8_t i = 0; (i < monitored_msg_sz) && !is_dhcp_unhealthy; i++) { - is_dhcp_unhealthy = tx_counters[monitored_msgs[i]] > tx_counter_snapshot[monitored_msgs[i]]; + switch (type) + { + case DHCPv4_TYPE: + tx_counters = v4counters[DHCP_COUNTERS_CURRENT][DHCP_TX]; + tx_counter_snapshot = v4counters[DHCP_COUNTERS_SNAPSHOT][DHCP_TX]; + for (uint8_t i = 0; (i < v4_monitored_msg_sz) && !is_dhcp_unhealthy; i++) { + is_dhcp_unhealthy = tx_counters[v4_monitored_msgs[i]] > tx_counter_snapshot[v4_monitored_msgs[i]]; + } + break; + case DHCPv6_TYPE: + tx_counters = v6counters[DHCP_COUNTERS_CURRENT][DHCP_TX]; + tx_counter_snapshot = v6counters[DHCP_COUNTERS_SNAPSHOT][DHCP_TX]; + for (uint8_t i = 0; (i < v6_monitored_msg_sz) && !is_dhcp_unhealthy; i++) { + is_dhcp_unhealthy = tx_counters[v6_monitored_msgs[i]] > tx_counter_snapshot[v6_monitored_msgs[i]]; + } + break; + default: + syslog(LOG_ERR, "Unknown DHCP type %d\n", type); + break; } // for negative validation, return unhealthy if DHCP packet are being @@ -323,7 +532,7 @@ static dhcp_mon_status_t dhcp_device_check_negative_health(uint64_t counters[][D } /** - * @code dhcp_device_check_health(check_type, counters, counters_snapshot); + * @code dhcp_device_check_health(check_type, v4counters, v6counters, type); * * @brief Check that DHCP relay is functioning properly given a check type. Positive check * indicates for every rx of DHCP message of type 'type', there would increment of @@ -332,59 +541,80 @@ static dhcp_mon_status_t dhcp_device_check_negative_health(uint64_t counters[][D * considered unhealthy. * * @param check_type type of health check - * @param counters current/snapshot counter + * @param v4counters current/snapshot counters + * @param v6counters current/snapshot counters + * @param type DHCP type * * @return DHCP_MON_STATUS_HEALTHY, DHCP_MON_STATUS_UNHEALTHY, or DHCP_MON_STATUS_INDETERMINATE */ static dhcp_mon_status_t dhcp_device_check_health(dhcp_mon_check_t check_type, - uint64_t counters[][DHCP_DIR_COUNT][DHCP_MESSAGE_TYPE_COUNT]) + uint64_t v4counters[][DHCP_DIR_COUNT][DHCPv4_MESSAGE_TYPE_COUNT], + uint64_t v6counters[][DHCP_DIR_COUNT][DHCPv6_MESSAGE_TYPE_COUNT], + dhcp_type_t type) { dhcp_mon_status_t rv = DHCP_MON_STATUS_HEALTHY; - if (dhcp_device_is_dhcp_inactive(aggregate_dev.counters)) { + if (dhcp_device_is_dhcp_inactive(aggregate_dev.counters.v4counters, aggregate_dev.counters.v6counters, type)) { rv = DHCP_MON_STATUS_INDETERMINATE; } else if (check_type == DHCP_MON_CHECK_POSITIVE) { - rv = dhcp_device_check_positive_health(counters); + rv = dhcp_device_check_positive_health(v4counters, v6counters, type); } else if (check_type == DHCP_MON_CHECK_NEGATIVE) { - rv = dhcp_device_check_negative_health(counters); + rv = dhcp_device_check_negative_health(v4counters, v6counters, type); } return rv; } /** - * @code dhcp_print_counters(vlan_intf, type, counters); + * @code dhcp_print_counters(vlan_intf, type, v4counters, v6counters); * * @brief prints DHCP counters to sylsog. * - * @param vlan_intf vlan interface name - * @param type counter type - * @param counters interface counter + * @param vlan_intf vlan interface name + * @param type counter type + * @param v4counters interface counter + * @param v6counters interface counter * * @return none */ static void dhcp_print_counters(const char *vlan_intf, dhcp_counters_type_t type, - uint64_t counters[][DHCP_MESSAGE_TYPE_COUNT]) + uint64_t v4counters[][DHCPv4_MESSAGE_TYPE_COUNT], + uint64_t v6counters[][DHCPv6_MESSAGE_TYPE_COUNT]) { - static const char *counter_desc[DHCP_COUNTERS_COUNT] = { + static const char *v4_counter_desc[DHCP_COUNTERS_COUNT] = { + [DHCP_COUNTERS_CURRENT] = " Current", + [DHCP_COUNTERS_SNAPSHOT] = "Snapshot" + }; + static const char *v6_counter_desc[DHCP_COUNTERS_COUNT] = { [DHCP_COUNTERS_CURRENT] = " Current", [DHCP_COUNTERS_SNAPSHOT] = "Snapshot" }; syslog( LOG_NOTICE, - "[%*s-%*s rx/tx] Discover: %*lu/%*lu, Offer: %*lu/%*lu, Request: %*lu/%*lu, ACK: %*lu/%*lu\n", + "DHCPv4 [%*s-%*s rx/tx] Discover: %*lu/%*lu, Offer: %*lu/%*lu, Request: %*lu/%*lu, ACK: %*lu/%*lu\n\ + DHCPv6 [%*s-%*s rx/tx] Solicit: %*lu/%*lu, Advertise: %*lu/%*lu, Request: %*lu/%*lu, Reply: %*lu/%*lu\n", + IF_NAMESIZE, vlan_intf, + (int) strlen(v4_counter_desc[type]), v4_counter_desc[type], + DHCP_COUNTER_WIDTH, v4counters[DHCP_RX][DHCPv4_MESSAGE_TYPE_DISCOVER], + DHCP_COUNTER_WIDTH, v4counters[DHCP_TX][DHCPv4_MESSAGE_TYPE_DISCOVER], + DHCP_COUNTER_WIDTH, v4counters[DHCP_RX][DHCPv4_MESSAGE_TYPE_OFFER], + DHCP_COUNTER_WIDTH, v4counters[DHCP_TX][DHCPv4_MESSAGE_TYPE_OFFER], + DHCP_COUNTER_WIDTH, v4counters[DHCP_RX][DHCPv4_MESSAGE_TYPE_REQUEST], + DHCP_COUNTER_WIDTH, v4counters[DHCP_TX][DHCPv4_MESSAGE_TYPE_REQUEST], + DHCP_COUNTER_WIDTH, v4counters[DHCP_RX][DHCPv4_MESSAGE_TYPE_ACK], + DHCP_COUNTER_WIDTH, v4counters[DHCP_TX][DHCPv4_MESSAGE_TYPE_ACK], IF_NAMESIZE, vlan_intf, - (int) strlen(counter_desc[type]), counter_desc[type], - DHCP_COUNTER_WIDTH, counters[DHCP_RX][DHCP_MESSAGE_TYPE_DISCOVER], - DHCP_COUNTER_WIDTH, counters[DHCP_TX][DHCP_MESSAGE_TYPE_DISCOVER], - DHCP_COUNTER_WIDTH, counters[DHCP_RX][DHCP_MESSAGE_TYPE_OFFER], - DHCP_COUNTER_WIDTH, counters[DHCP_TX][DHCP_MESSAGE_TYPE_OFFER], - DHCP_COUNTER_WIDTH, counters[DHCP_RX][DHCP_MESSAGE_TYPE_REQUEST], - DHCP_COUNTER_WIDTH, counters[DHCP_TX][DHCP_MESSAGE_TYPE_REQUEST], - DHCP_COUNTER_WIDTH, counters[DHCP_RX][DHCP_MESSAGE_TYPE_ACK], - DHCP_COUNTER_WIDTH, counters[DHCP_TX][DHCP_MESSAGE_TYPE_ACK] + (int) strlen(v6_counter_desc[type]), v6_counter_desc[type], + DHCP_COUNTER_WIDTH, v6counters[DHCP_RX][DHCPv6_MESSAGE_TYPE_SOLICIT], + DHCP_COUNTER_WIDTH, v6counters[DHCP_TX][DHCPv6_MESSAGE_TYPE_SOLICIT], + DHCP_COUNTER_WIDTH, v6counters[DHCP_RX][DHCPv6_MESSAGE_TYPE_ADVERTISE], + DHCP_COUNTER_WIDTH, v6counters[DHCP_TX][DHCPv6_MESSAGE_TYPE_ADVERTISE], + DHCP_COUNTER_WIDTH, v6counters[DHCP_RX][DHCPv6_MESSAGE_TYPE_REQUEST], + DHCP_COUNTER_WIDTH, v6counters[DHCP_TX][DHCPv6_MESSAGE_TYPE_REQUEST], + DHCP_COUNTER_WIDTH, v6counters[DHCP_RX][DHCPv6_MESSAGE_TYPE_REPLY], + DHCP_COUNTER_WIDTH, v6counters[DHCP_TX][DHCPv6_MESSAGE_TYPE_REPLY] ); } @@ -454,12 +684,12 @@ int initialize_intf_mac_and_ip_addr(dhcp_device_context_t *context) strncpy(ifr.ifr_name, context->intf, sizeof(ifr.ifr_name) - 1); ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0'; - // Get network address + // Get v4 network address if (ioctl(fd, SIOCGIFADDR, &ifr) == -1) { syslog(LOG_ALERT, "ioctl: %s", explain_ioctl(fd, SIOCGIFADDR, &ifr)); break; } - context->ip = ((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr.s_addr; + context->ipv4 = ((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr.s_addr; // Get mac address if (ioctl(fd, SIOCGIFHWADDR, &ifr) == -1) { @@ -470,6 +700,30 @@ int initialize_intf_mac_and_ip_addr(dhcp_device_context_t *context) close(fd); + // Get v6 network address + memset(&context->ipv6, 0, sizeof(context->ipv6)); + struct ifaddrs *ifa, *ifa_tmp; + + if (getifaddrs(&ifa) == -1) { + syslog(LOG_ALERT, "getifaddrs failed"); + break; + } + + ifa_tmp = ifa; + while (ifa_tmp) { + // Check if current interface has a valid IPv6 address (not link local address) + if ((strncmp(ifa_tmp->ifa_name, context->intf, sizeof(context->intf)) == 0) && + (ifa_tmp->ifa_addr) && + (ifa_tmp->ifa_addr->sa_family == AF_INET6) && + (((struct sockaddr_in6*)(ifa_tmp->ifa_addr))->sin6_addr.__in6_u.__u6_addr16[0] != IPV6_LINK_LOCAL_PREFIX)) { + + struct sockaddr_in6 *in6 = (struct sockaddr_in6*) ifa_tmp->ifa_addr; + memcpy(&context->ipv6, &in6->sin6_addr, sizeof(context->ipv6)); + } + ifa_tmp = ifa_tmp->ifa_next; + } + freeifaddrs(ifa); + rv = 0; } while (0); @@ -477,20 +731,41 @@ int initialize_intf_mac_and_ip_addr(dhcp_device_context_t *context) } /** - * @code dhcp_device_get_ip(context); + * @code dhcp_device_get_ipv4(context); * * @brief Accessor method * * @param context pointer to device (interface) context * - * @return interface IP + * @return interface IPv4 */ -int dhcp_device_get_ip(dhcp_device_context_t *context, in_addr_t *ip) +int dhcp_device_get_ipv4(dhcp_device_context_t *context, in_addr_t *ip) { int rv = -1; if (context != NULL && ip != NULL) { - *ip = context->ip; + *ip = context->ipv4; + rv = 0; + } + + return rv; +} + +/** + * @code dhcp_device_get_ipv6(context); + * + * @brief Accessor method + * + * @param context pointer to device (interface) context + * + * @return interface IPv6 + */ +int dhcp_device_get_ipv6(dhcp_device_context_t *context, struct in6_addr *ip) +{ + int rv = -1; + + if (context != NULL && ip != NULL) { + *ip = context->ipv6; rv = 0; } @@ -528,7 +803,8 @@ int dhcp_device_init(dhcp_device_context_t **context, const char *intf, uint8_t dev_context->is_uplink = is_uplink; - memset(dev_context->counters, 0, sizeof(dev_context->counters)); + memset(dev_context->counters.v4counters, 0, sizeof(dev_context->counters.v4counters)); + memset(dev_context->counters.v6counters, 0, sizeof(dev_context->counters.v6counters)); *context = dev_context; rv = 0; @@ -543,14 +819,15 @@ int dhcp_device_init(dhcp_device_context_t **context, const char *intf, uint8_t } /** - * @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 */ 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) { int rv = -1; @@ -560,12 +837,20 @@ int dhcp_device_start_capture(dhcp_device_context_t *context, break; } - if (snaplen < UDP_START_OFFSET + sizeof(struct udphdr) + DHCP_OPTIONS_HEADER_SIZE) { - syslog(LOG_ALERT, "dhcp_device_start_capture(%s): snap length is too low to capture DHCP options", context->intf); + // snaplen check for DHCPv4 size + if (dhcpv4_enabled && snaplen < UDPv4_START_OFFSET + sizeof(struct udphdr) + DHCPv4_OPTIONS_HEADER_SIZE) { + syslog(LOG_ALERT, "dhcp_device_start_capture(%s): snap length is too low to capture DHCPv4 options", context->intf); + break; + } + + // snaplen check for DHCPv6 size - DHCPv6 message type is the first byte of the udp payload + if (dhcpv6_enabled && snaplen < DHCPv6_START_OFFSET + 1) { + syslog(LOG_ALERT, "dhcp_device_start_capture(%s): snap length is too low to capture DHCPv6 option", context->intf); break; } context->giaddr_ip = giaddr_ip; + context->v6_vlan_ip = v6_vlan_ip; context->buffer = (uint8_t *) malloc(snaplen); if (context->buffer == NULL) { @@ -603,17 +888,17 @@ 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 */ -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) { dhcp_mon_status_t rv = DHCP_MON_STATUS_HEALTHY; if (context != NULL) { - rv = dhcp_device_check_health(check_type, context->counters); + rv = dhcp_device_check_health(check_type, context->counters.v4counters, context->counters.v6counters, type); } return rv; @@ -627,9 +912,17 @@ dhcp_mon_status_t dhcp_device_get_status(dhcp_mon_check_t check_type, dhcp_devic void dhcp_device_update_snapshot(dhcp_device_context_t *context) { if (context != NULL) { - memcpy(context->counters[DHCP_COUNTERS_SNAPSHOT], - context->counters[DHCP_COUNTERS_CURRENT], - sizeof(context->counters[DHCP_COUNTERS_SNAPSHOT])); + if (dhcpv4_enabled) { + memcpy(context->counters.v4counters[DHCP_COUNTERS_SNAPSHOT], + context->counters.v4counters[DHCP_COUNTERS_CURRENT], + sizeof(context->counters.v4counters[DHCP_COUNTERS_SNAPSHOT])); + } + + if (dhcpv6_enabled) { + memcpy(context->counters.v6counters[DHCP_COUNTERS_SNAPSHOT], + context->counters.v6counters[DHCP_COUNTERS_CURRENT], + sizeof(context->counters.v6counters[DHCP_COUNTERS_SNAPSHOT])); + } } } @@ -641,6 +934,17 @@ void dhcp_device_update_snapshot(dhcp_device_context_t *context) void dhcp_device_print_status(dhcp_device_context_t *context, dhcp_counters_type_t type) { if (context != NULL) { - dhcp_print_counters(context->intf, type, context->counters[type]); + dhcp_print_counters(context->intf, type, context->counters.v4counters[type], context->counters.v6counters[type]); } } + +/** + * @code dhcp_device_active_types(dhcpv4, dhcpv6); + * + * @brief update local variables with active protocols + */ +void dhcp_device_active_types(bool dhcpv4, bool dhcpv6) +{ + dhcpv4_enabled = dhcpv4; + dhcpv6_enabled = dhcpv6; +} diff --git a/src/dhcp_device.h b/src/dhcp_device.h index aa686f4e2..f8aa874bf 100644 --- a/src/dhcp_device.h +++ b/src/dhcp_device.h @@ -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 @@ -60,6 +82,13 @@ 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 { @@ -67,19 +96,28 @@ typedef enum 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(); @@ -130,7 +180,7 @@ 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 * @@ -138,13 +188,15 @@ int dhcp_device_init(dhcp_device_context_t **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_ */ diff --git a/src/dhcp_devman.c b/src/dhcp_devman.c index 65484798d..e7a253222 100644 --- a/src/dhcp_devman.c +++ b/src/dhcp_devman.c @@ -9,6 +9,8 @@ #include #include #include +#include +#include #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); +} diff --git a/src/dhcp_devman.h b/src/dhcp_devman.h index 948e79cde..6e30c654f 100644 --- a/src/dhcp_devman.h +++ b/src/dhcp_devman.h @@ -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_ */ diff --git a/src/dhcp_mon.c b/src/dhcp_mon.c index 74d986974..2777b6484 100644 --- a/src/dhcp_mon.c +++ b/src/dhcp_mon.c @@ -12,16 +12,24 @@ #include #include #include +#include #include "dhcp_mon.h" #include "dhcp_devman.h" +/** DHCP device/interface state counters */ +typedef struct +{ + int v4_count; /** count in the number of DHCPv4 unhealthy checks */ + int v6_count; /** count in the number of DHCPv6 unhealthy checks */ +} dhcp_mon_count_t; + /** DHCP device/interface state */ typedef struct { dhcp_mon_check_t check_type; /** check type */ dhcp_device_context_t* (*get_context)(); /** functor to a device context accessor function */ - int count; /** count in the number of unhealthy checks */ + dhcp_mon_count_t counters; /** count in the number of unhealthy checks */ const char *msg; /** message to be printed if unhealthy state is determined */ } dhcp_mon_state_t; @@ -29,6 +37,10 @@ typedef struct static int window_interval_sec = 18; /** dhcp_unhealthy_max_count max count of consecutive unhealthy statuses before reporting to syslog */ static int dhcp_unhealthy_max_count = 10; +/** DHCP versions flags */ +static bool dhcpv4_enabled; +static bool dhcpv6_enabled; + /** libevent base struct */ static struct event_base *base; /** libevent timeout event struct */ @@ -45,13 +57,15 @@ static dhcp_mon_state_t state_data[] = { [0] = { .check_type = DHCP_MON_CHECK_POSITIVE, .get_context = dhcp_devman_get_agg_dev, - .count = 0, + .counters.v4_count = 0, + .counters.v6_count = 0, .msg = "dhcpmon detected disparity in DHCP Relay behavior. Duration: %d (sec) for vlan: '%s'\n" }, [1] = { .check_type = DHCP_MON_CHECK_NEGATIVE, .get_context = dhcp_devman_get_mgmt_dev, - .count = 0, + .counters.v4_count = 0, + .counters.v6_count = 0, .msg = "dhcpmon detected DHCP packets traveling through mgmt interface (please check BGP routes.)" " Duration: %d (sec) for intf: '%s'\n" } @@ -78,36 +92,89 @@ static void signal_callback(evutil_socket_t fd, short event, void *arg) } /** - * @code check_dhcp_relay_health(state_data); + * @code check_dhcp_relay_health(state_data, dhcp_type); * * @brief check DHCP relay overall health * * @param state_data pointer to dhcpmon state data * + * @param type DHCP type + * * @return none */ -static void check_dhcp_relay_health(dhcp_mon_state_t *state_data) +static void check_dhcp_relay_health(dhcp_mon_state_t *state_data, dhcp_type_t type) { dhcp_device_context_t *context = state_data->get_context(); - dhcp_mon_status_t dhcp_mon_status = dhcp_devman_get_status(state_data->check_type, context); + dhcp_mon_status_t dhcp_mon_status = dhcp_devman_get_status(state_data->check_type, context, type); switch (dhcp_mon_status) { case DHCP_MON_STATUS_UNHEALTHY: - if (++state_data->count > dhcp_unhealthy_max_count) { - syslog(LOG_ALERT, state_data->msg, state_data->count * window_interval_sec, context->intf); - dhcp_devman_print_status(context, DHCP_COUNTERS_SNAPSHOT); - dhcp_devman_print_status(context, DHCP_COUNTERS_CURRENT); + switch (type) + { + case DHCPv4_TYPE: + if (++state_data->counters.v4_count > dhcp_unhealthy_max_count) { + syslog(LOG_ALERT, state_data->msg, state_data->counters.v4_count * window_interval_sec, context->intf); + dhcp_devman_print_status(context, DHCP_COUNTERS_SNAPSHOT); + dhcp_devman_print_status(context, DHCP_COUNTERS_CURRENT); + } + break; + case DHCPv6_TYPE: + if (++state_data->counters.v6_count > dhcp_unhealthy_max_count) { + syslog(LOG_ALERT, state_data->msg, state_data->counters.v6_count * window_interval_sec, context->intf); + dhcp_devman_print_status(context, DHCP_COUNTERS_SNAPSHOT); + dhcp_devman_print_status(context, DHCP_COUNTERS_CURRENT); + } + break; + + default: + syslog(LOG_ERR, "Unknown DHCP type %d\n", type); + break; } break; + case DHCP_MON_STATUS_HEALTHY: - state_data->count = 0; + switch (type) + { + case DHCPv4_TYPE: + state_data->counters.v4_count = 0; + break; + case DHCPv6_TYPE: + state_data->counters.v6_count = 0; + break; + default: + syslog(LOG_ERR, "Unknown DHCP type %d\n", type); + break; + } break; + case DHCP_MON_STATUS_INDETERMINATE: - if (state_data->count) { - state_data->count++; + switch (type) + { + case DHCPv4_TYPE: + if (state_data->counters.v4_count) { + if (++state_data->counters.v4_count > dhcp_unhealthy_max_count) { + syslog(LOG_ALERT, state_data->msg, state_data->counters.v4_count * window_interval_sec, context->intf); + dhcp_devman_print_status(context, DHCP_COUNTERS_SNAPSHOT); + dhcp_devman_print_status(context, DHCP_COUNTERS_CURRENT); + } + } + break; + case DHCPv6_TYPE: + if (state_data->counters.v6_count) { + if (++state_data->counters.v6_count > dhcp_unhealthy_max_count) { + syslog(LOG_ALERT, state_data->msg, state_data->counters.v6_count * window_interval_sec, context->intf); + dhcp_devman_print_status(context, DHCP_COUNTERS_SNAPSHOT); + dhcp_devman_print_status(context, DHCP_COUNTERS_CURRENT); + } + } + break; + default: + syslog(LOG_ERR, "Unknown DHCP type %d\n", type); + break; } break; + default: syslog(LOG_ERR, "DHCP Relay returned unknown status %d\n", dhcp_mon_status); break; @@ -128,7 +195,12 @@ static void check_dhcp_relay_health(dhcp_mon_state_t *state_data) static void timeout_callback(evutil_socket_t fd, short event, void *arg) { for (uint8_t i = 0; i < sizeof(state_data) / sizeof(*state_data); i++) { - check_dhcp_relay_health(&state_data[i]); + if (dhcpv4_enabled) { + check_dhcp_relay_health(&state_data[i], DHCPv4_TYPE); + } + if (dhcpv6_enabled) { + check_dhcp_relay_health(&state_data[i], DHCPv6_TYPE); + } } dhcp_devman_update_snapshot(NULL); @@ -141,13 +213,17 @@ static void timeout_callback(evutil_socket_t fd, short event, void *arg) * seconds. It also writes to syslog when dhcp relay has been unhealthy for consecutive max_count checks. * */ -int dhcp_mon_init(int window_sec, int max_count) +int dhcp_mon_init(int window_sec, int max_count, bool dhcpv4, bool dhcpv6) { int rv = -1; do { window_interval_sec = window_sec; dhcp_unhealthy_max_count = max_count; + dhcpv4_enabled = dhcpv4; + dhcpv6_enabled = dhcpv6; + + dhcp_devman_active_types(dhcpv4, dhcpv6); base = event_base_new(); if (base == NULL) { diff --git a/src/dhcp_mon.h b/src/dhcp_mon.h index ae8911ab5..facd46da6 100644 --- a/src/dhcp_mon.h +++ b/src/dhcp_mon.h @@ -17,10 +17,12 @@ * * @param window_sec time interval between health checks * @param max_count max count of consecutive unhealthy statuses before reporting to syslog + * @param dhcpv4 flag indicating dhcpv4 is enabled + * @param dhcpv6 flag indicating dhcpv6 is enabled * * @return 0 upon success, otherwise upon failure */ -int dhcp_mon_init(int window_sec, int max_count); +int dhcp_mon_init(int window_sec, int max_count, bool dhcpv4, bool dhcpv6); /** * @code dhcp_mon_shutdown(); diff --git a/src/main.c b/src/main.c index 29bc534ac..1cf931821 100644 --- a/src/main.c +++ b/src/main.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "dhcp_mon.h" #include "dhcp_devman.h" @@ -41,7 +42,8 @@ static const uint32_t dhcpmon_default_unhealthy_max_count = 10; static void usage(const char *prog) { printf("Usage: %s -id {-iu }+ -im [-u ]" - "[-w ] [-c ] [-s ] [-d]\n", prog); + "[-w ] [-c ] [-s ]" + "[-4 ] [-6 ] [-d]\n", prog); printf("where\n"); printf("\tsouth interface: is a vlan interface,\n"); printf("\tnorth interface: is a TOR-T1 interface,\n"); @@ -112,6 +114,8 @@ int main(int argc, char **argv) int max_unhealthy_count = dhcpmon_default_unhealthy_max_count; size_t snaplen = dhcpmon_default_snaplen; int make_daemon = 0; + bool dhcpv4_enabled = false; + bool dhcpv6_enabled = false; setlogmask(LOG_UPTO(LOG_INFO)); openlog(basename(argv[0]), LOG_CONS | LOG_PID | LOG_NDELAY, LOG_DAEMON); @@ -155,6 +159,14 @@ int main(int argc, char **argv) max_unhealthy_count = atoi(argv[i + 1]); i += 2; break; + case '4': + dhcpv4_enabled = true; + i++; + break; + case '6': + dhcpv6_enabled = true; + i++; + break; default: fprintf(stderr, "%s: %c: Unknown option\n", basename(argv[0]), argv[i][1]); usage(basename(argv[0])); @@ -165,7 +177,11 @@ int main(int argc, char **argv) dhcpmon_daemonize(); } - if ((dhcp_mon_init(window_interval, max_unhealthy_count) == 0) && + if (!dhcpv4_enabled && !dhcpv6_enabled) { + dhcpv4_enabled = true; + } + + if ((dhcp_mon_init(window_interval, max_unhealthy_count, dhcpv4_enabled, dhcpv6_enabled) == 0) && (dhcp_mon_start(snaplen) == 0)) { rv = EXIT_SUCCESS;