userapps/opensource/net-snmp/agent/mibgroup/mibII/kernel_linux.c

   1 /*
   2  *  Linux kernel interface
   3  *
   4  */
   5
   6 #include <net-snmp/net-snmp-config.h>
   7 #include <net-snmp/net-snmp-includes.h>
   8 #include <net-snmp/agent/net-snmp-agent-includes.h>
   9
  10 #include "util_funcs.h"
  11
  12 #if HAVE_STRING_H
  13 #include <string.h>
  14 #endif
  15 #include <sys/types.h>
  16 #if HAVE_SYS_PARAM_H
  17 #include <sys/param.h>
  18 #endif
  19
  20 #include "kernel_linux.h"
  21
  22 struct ip_mib   cached_ip_mib;
  23 struct icmp_mib cached_icmp_mib;
  24 struct tcp_mib  cached_tcp_mib;
  25 struct udp_mib  cached_udp_mib;
  26
  27 #define IP_STATS_LINE   "Ip: %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu"
  28 #define ICMP_STATS_LINE "Icmp: %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu"
  29 #define TCP_STATS_LINE  "Tcp: %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu"
  30 #define UDP_STATS_LINE  "Udp: %lu %lu %lu %lu"
  31
  32 #define IP_STATS_PREFIX_LEN     4
  33 #define ICMP_STATS_PREFIX_LEN   6
  34 #define TCP_STATS_PREFIX_LEN    5
  35 #define UDP_STATS_PREFIX_LEN    5
  36
  37 #ifndef MIB_STATS_CACHE_TIMEOUT
  38 #define MIB_STATS_CACHE_TIMEOUT 5
  39 #endif
  40 #ifndef LINUX_STATS_CACHE_TIMEOUT
  41 #define LINUX_STATS_CACHE_TIMEOUT       MIB_STATS_CACHE_TIMEOUT
  42 #endif
  43 marker_t        linux_mibII_stats_cache_marker = NULL;
  44
  45 int
  46 linux_read_mibII_stats(void)
  47 {
  48     FILE           *in = fopen("/proc/net/snmp", "r");
  49     char            line[1024];
  50
  51     if (!in) {
  52         free(linux_mibII_stats_cache_marker);
  53         linux_mibII_stats_cache_marker = NULL;
  54         return -1;
  55     }
  56
  57     if (linux_mibII_stats_cache_marker &&
  58         (!atime_ready
  59          (linux_mibII_stats_cache_marker,
  60           LINUX_STATS_CACHE_TIMEOUT * 1000))) {
  61         fclose(in);
  62         return 0;
  63     }
  64
  65     if (linux_mibII_stats_cache_marker)
  66         atime_setMarker(linux_mibII_stats_cache_marker);
  67     else
  68         linux_mibII_stats_cache_marker = atime_newMarker();
  69
  70
  71     while (line == fgets(line, sizeof(line), in)) {
  72         if (!strncmp(line, IP_STATS_LINE, IP_STATS_PREFIX_LEN)) {
  73             sscanf(line, IP_STATS_LINE,
  74                    &cached_ip_mib.ipForwarding,
  75                    &cached_ip_mib.ipDefaultTTL,
  76                    &cached_ip_mib.ipInReceives,
  77                    &cached_ip_mib.ipInHdrErrors,
  78                    &cached_ip_mib.ipInAddrErrors,
  79                    &cached_ip_mib.ipForwDatagrams,
  80                    &cached_ip_mib.ipInUnknownProtos,
  81                    &cached_ip_mib.ipInDiscards,
  82                    &cached_ip_mib.ipInDelivers,
  83                    &cached_ip_mib.ipOutRequests,
  84                    &cached_ip_mib.ipOutDiscards,
  85                    &cached_ip_mib.ipOutNoRoutes,
  86                    &cached_ip_mib.ipReasmTimeout,
  87                    &cached_ip_mib.ipReasmReqds,
  88                    &cached_ip_mib.ipReasmOKs,
  89                    &cached_ip_mib.ipReasmFails,
  90                    &cached_ip_mib.ipFragOKs,
  91                    &cached_ip_mib.ipFragFails,
  92                    &cached_ip_mib.ipFragCreates);
  93             cached_ip_mib.ipRoutingDiscards = 0;        /* XXX */
  94         } else if (!strncmp(line, ICMP_STATS_LINE, ICMP_STATS_PREFIX_LEN)) {
  95             sscanf(line, ICMP_STATS_LINE,
  96                    &cached_icmp_mib.icmpInMsgs,
  97                    &cached_icmp_mib.icmpInErrors,
  98                    &cached_icmp_mib.icmpInDestUnreachs,
  99                    &cached_icmp_mib.icmpInTimeExcds,
 100                    &cached_icmp_mib.icmpInParmProbs,
 101                    &cached_icmp_mib.icmpInSrcQuenchs,
 102                    &cached_icmp_mib.icmpInRedirects,
 103                    &cached_icmp_mib.icmpInEchos,
 104                    &cached_icmp_mib.icmpInEchoReps,
 105                    &cached_icmp_mib.icmpInTimestamps,
 106                    &cached_icmp_mib.icmpInTimestampReps,
 107                    &cached_icmp_mib.icmpInAddrMasks,
 108                    &cached_icmp_mib.icmpInAddrMaskReps,
 109                    &cached_icmp_mib.icmpOutMsgs,
 110                    &cached_icmp_mib.icmpOutErrors,
 111                    &cached_icmp_mib.icmpOutDestUnreachs,
 112                    &cached_icmp_mib.icmpOutTimeExcds,
 113                    &cached_icmp_mib.icmpOutParmProbs,
 114                    &cached_icmp_mib.icmpOutSrcQuenchs,
 115                    &cached_icmp_mib.icmpOutRedirects,
 116                    &cached_icmp_mib.icmpOutEchos,
 117                    &cached_icmp_mib.icmpOutEchoReps,
 118                    &cached_icmp_mib.icmpOutTimestamps,
 119                    &cached_icmp_mib.icmpOutTimestampReps,
 120                    &cached_icmp_mib.icmpOutAddrMasks,
 121                    &cached_icmp_mib.icmpOutAddrMaskReps);
 122         } else if (!strncmp(line, TCP_STATS_LINE, TCP_STATS_PREFIX_LEN)) {
 123             int             ret = sscanf(line, TCP_STATS_LINE,
 124                                          &cached_tcp_mib.tcpRtoAlgorithm,
 125                                          &cached_tcp_mib.tcpRtoMin,
 126                                          &cached_tcp_mib.tcpRtoMax,
 127                                          &cached_tcp_mib.tcpMaxConn,
 128                                          &cached_tcp_mib.tcpActiveOpens,
 129                                          &cached_tcp_mib.tcpPassiveOpens,
 130                                          &cached_tcp_mib.tcpAttemptFails,
 131                                          &cached_tcp_mib.tcpEstabResets,
 132                                          &cached_tcp_mib.tcpCurrEstab,
 133                                          &cached_tcp_mib.tcpInSegs,
 134                                          &cached_tcp_mib.tcpOutSegs,
 135                                          &cached_tcp_mib.tcpRetransSegs,
 136                                          &cached_tcp_mib.tcpInErrs,
 137                                          &cached_tcp_mib.tcpOutRsts);
 138             cached_tcp_mib.tcpInErrsValid = (ret > 12) ? 1 : 0;
 139             cached_tcp_mib.tcpOutRstsValid = (ret > 13) ? 1 : 0;
 140         } else if (!strncmp(line, UDP_STATS_LINE, UDP_STATS_PREFIX_LEN)) {
 141             sscanf(line, UDP_STATS_LINE,
 142                    &cached_udp_mib.udpInDatagrams,
 143                    &cached_udp_mib.udpNoPorts,
 144                    &cached_udp_mib.udpInErrors,
 145                    &cached_udp_mib.udpOutDatagrams);
 146         }
 147     }
 148     fclose(in);
 149
 150     /*
 151      * Tweak illegal values:
 152      *
 153      * valid values for ipForwarding are 1 == yup, 2 == nope
 154      * a 0 is forbidden, so patch:
 155      */
 156     if (!cached_ip_mib.ipForwarding)
 157         cached_ip_mib.ipForwarding = 2;
 158
 159     /*
 160      * 0 is illegal for tcpRtoAlgorithm
 161      * so assume `other' algorithm:
 162      */
 163     if (!cached_tcp_mib.tcpRtoAlgorithm)
 164         cached_tcp_mib.tcpRtoAlgorithm = 1;
 165     return 0;
 166 }
 167
 168 int
 169 linux_read_ip_stat(struct ip_mib *ipstat)
 170 {
 171     memset((char *) ipstat, (0), sizeof(*ipstat));
 172     if (linux_read_mibII_stats() == -1)
 173         return -1;
 174     memcpy((char *) ipstat, (char *) &cached_ip_mib, sizeof(*ipstat));
 175     return 0;
 176 }
 177
 178 int
 179 linux_read_icmp_stat(struct icmp_mib *icmpstat)
 180 {
 181     memset((char *) icmpstat, (0), sizeof(*icmpstat));
 182     if (linux_read_mibII_stats() == -1)
 183         return -1;
 184     memcpy((char *) icmpstat, (char *) &cached_icmp_mib,
 185            sizeof(*icmpstat));
 186     return 0;
 187 }
 188
 189 int
 190 linux_read_tcp_stat(struct tcp_mib *tcpstat)
 191 {
 192     memset((char *) tcpstat, (0), sizeof(*tcpstat));
 193     if (linux_read_mibII_stats() == -1)
 194         return -1;
 195     memcpy((char *) tcpstat, (char *) &cached_tcp_mib, sizeof(*tcpstat));
 196     return 0;
 197 }
 198
 199 int
 200 linux_read_udp_stat(struct udp_mib *udpstat)
 201 {
 202     memset((char *) udpstat, (0), sizeof(*udpstat));
 203     if (linux_read_mibII_stats() == -1)
 204         return -1;
 205     memcpy((char *) udpstat, (char *) &cached_udp_mib, sizeof(*udpstat));
 206     return 0;
 207 }