Merge pull request #2125 from RincewindsHat/refactor/check_icmp

Refactor check_icmp:

 - Far less global variables
 - Proper IPv6/legacy IP dual stack functionality (allowed mixed v4/v6 hosts)
 - Improved readability/understandability
 - General cleanup

1 files changed, 111 insertions, 0 deletions

diff --git a/plugins-root/check_icmp.d/config.h b/plugins-root/check_icmp.d/config.h
new file mode 100644
index 00000000..fc9dd5a6
--- /dev/null
+++ b/plugins-root/check_icmp.d/config.h
@@ -0,0 +1,111 @@
+#pragma once
+
+#include "../../config.h"
+#include "../../lib/states.h"
+#include <stddef.h>
+#include <netinet/in_systm.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/ip_icmp.h>
+#include <netinet/icmp6.h>
+#include <arpa/inet.h>
+#include <stdint.h>
+#include "./check_icmp_helpers.h"
+
+/* threshold structure. all values are maximum allowed, exclusive */
+typedef struct {
+        unsigned char pl; /* max allowed packet loss in percent */
+        time_t rta; /* roundtrip time average, microseconds */
+        double jitter;    /* jitter time average, microseconds */
+        double mos;       /* MOS */
+        double score;     /* Score */
+} check_icmp_threshold;
+
+/* the different modes of this program are as follows:
+ * MODE_RTA: send all packets no matter what (mimic check_icmp and check_ping)
+ * MODE_HOSTCHECK: Return immediately upon any sign of life
+ *                 In addition, sends packets to ALL addresses assigned
+ *                 to this host (as returned by gethostbyname() or
+ *                 gethostbyaddr() and expects one host only to be checked at
+ *                 a time.  Therefore, any packet response what so ever will
+ *                 count as a sign of life, even when received outside
+ *                 crit.rta limit. Do not misspell any additional IP's.
+ * MODE_ALL:  Requires packets from ALL requested IP to return OK (default).
+ * MODE_ICMP: Default Mode
+ */
+typedef enum {
+        MODE_RTA,
+        MODE_HOSTCHECK,
+        MODE_ALL,
+        MODE_ICMP,
+} check_icmp_execution_mode;
+
+typedef struct {
+        bool order_mode;
+        bool mos_mode;
+        bool rta_mode;
+        bool pl_mode;
+        bool jitter_mode;
+        bool score_mode;
+} check_icmp_mode_switches;
+
+typedef struct {
+        check_icmp_mode_switches modes;
+
+        int min_hosts_alive;
+        check_icmp_threshold crit;
+        check_icmp_threshold warn;
+
+        unsigned long ttl;
+        unsigned short icmp_data_size;
+        unsigned short icmp_pkt_size;
+        time_t pkt_interval;
+        time_t target_interval;
+        unsigned short number_of_packets;
+
+        char *source_ip;
+        bool need_v4;
+        bool need_v6;
+
+        uint16_t sender_id; // PID of the main process, which is used as an ID in packets
+
+        check_icmp_execution_mode mode;
+
+        unsigned short number_of_targets;
+        ping_target *targets;
+
+        unsigned short number_of_hosts;
+        check_icmp_target_container *hosts;
+} check_icmp_config;
+
+check_icmp_config check_icmp_config_init();
+
+/* the data structure */
+typedef struct icmp_ping_data {
+        struct timeval stime; /* timestamp (saved in protocol struct as well) */
+        unsigned short ping_id;
+} icmp_ping_data;
+
+#define MAX_IP_PKT_SIZE        65536 /* (theoretical) max IP packet size */
+#define IP_HDR_SIZE            20
+#define MAX_PING_DATA          (MAX_IP_PKT_SIZE - IP_HDR_SIZE - ICMP_MINLEN)
+#define MIN_PING_DATA_SIZE     sizeof(struct icmp_ping_data)
+#define DEFAULT_PING_DATA_SIZE (MIN_PING_DATA_SIZE + 44)
+
+/* 80 msec packet interval by default */
+#define DEFAULT_PKT_INTERVAL    80000
+#define DEFAULT_TARGET_INTERVAL 0
+
+#define DEFAULT_WARN_RTA 200000
+#define DEFAULT_CRIT_RTA 500000
+#define DEFAULT_WARN_PL  40
+#define DEFAULT_CRIT_PL  80
+
+#define DEFAULT_TIMEOUT 10
+#define DEFAULT_TTL     64
+
+#define DEFAULT_NUMBER_OF_PACKETS 5
+
+#define PACKET_BACKOFF_FACTOR 1.5
+#define TARGET_BACKOFF_FACTOR 1.5