net-snmp-loadave-writable.patch

   1 This patch makes "load X Y Z" snmpsettable via snmpset,
   2
   3 it behaves the same as sysName.0, once written in snmpd.conf, it becames
   4 readonly.
   5
   6 Signed-off-by: Elan Ruusamäe <glen@delfi.ee>
   7 Upstream-Tracker: https://sourceforge.net/tracker/?func=detail&aid=2931446&group_id=12694&atid=312694
   8
   9 --- net-snmp-5.4.2.1/agent/mibgroup/ucd-snmp/loadave.c~ 2009-12-21 21:00:10.094254079 +0200
  10 +++ net-snmp-5.4.2.1/agent/mibgroup/ucd-snmp/loadave.c  2009-12-21 22:02:45.398903148 +0200
  11 @@ -135,7 +135,19 @@
  12  #include "util_funcs.h"
  13  #include "kernel.h"
  14
  15 -double          maxload[3];
  16 +static double maxload[3];
  17 +static int laConfigSet = 0;
  18 +
  19 +static int
  20 +loadave_store_config(int a, int b, void *c, void *d)
  21 +{
  22 +    char line[SNMP_MAXBUF_SMALL];
  23 +    if (laConfigSet > 0) {
  24 +        snprintf(line, SNMP_MAXBUF_SMALL, "pload %.02f %.02f %.02f", maxload[0], maxload[1], maxload[2]);
  25 +        snmpd_store_config(line);
  26 +    }
  27 +    return SNMPERR_SUCCESS;
  28 +}
  29
  30  void
  31  init_loadave(void)
  32 @@ -152,7 +164,7 @@
  33           {ERRORNAME}},
  34          {LOADAVE, ASN_OCTET_STR, RONLY, var_extensible_loadave, 1,
  35           {LOADAVE}},
  36 -        {LOADMAXVAL, ASN_OCTET_STR, RONLY, var_extensible_loadave, 1,
  37 +        {LOADMAXVAL, ASN_OCTET_STR, RWRITE, var_extensible_loadave, 1,
  38           {LOADMAXVAL}},
  39          {LOADAVEINT, ASN_INTEGER, RONLY, var_extensible_loadave, 1,
  40           {LOADAVEINT}},
  41 @@ -179,9 +191,22 @@
  42      REGISTER_MIB("ucd-snmp/loadave", extensible_loadave_variables,
  43                   variable2, loadave_variables_oid);
  44
  45 +    laConfigSet = 0;
  46 +
  47      snmpd_register_config_handler("load", loadave_parse_config,
  48                                    loadave_free_config,
  49                                    "max1 [max5] [max15]");
  50 +
  51 +    snmpd_register_config_handler("pload",
  52 +                                  loadave_parse_config, NULL, NULL);
  53 +
  54 +
  55 +    /*
  56 +     * we need to be called back later
  57 +     */
  58 +    snmp_register_callback(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_STORE_DATA,
  59 +                                       loadave_store_config, NULL);
  60 +
  61  }
  62
  63  void
  64 @@ -189,6 +214,25 @@
  65  {
  66      int             i;
  67
  68 +    if (strcmp(token, "pload") == 0) {
  69 +        if (laConfigSet < 0) {
  70 +            snmp_log(LOG_WARNING,
  71 +                     "ignoring attempted override of read-only load\n");
  72 +            return;
  73 +        } else {
  74 +            laConfigSet++;
  75 +        }
  76 +    } else {
  77 +        if (laConfigSet > 0) {
  78 +            snmp_log(LOG_WARNING,
  79 +                     "ignoring attempted override of read-only load\n");
  80 +            /*
  81 +             * Fall through and copy in this value.
  82 +             */
  83 +        }
  84 +        laConfigSet = -1;
  85 +    }
  86 +
  87      for (i = 0; i <= 2; i++) {
  88          if (cptr != NULL)
  89              maxload[i] = atof(cptr);
  90 @@ -309,6 +353,71 @@
  91      return 0;
  92  }
  93
  94 +static int
  95 +write_laConfig(int action,
  96 +                          u_char * var_val,
  97 +                          u_char var_val_type,
  98 +                          size_t var_val_len,
  99 +                          u_char * statP, oid * name, size_t name_len)
 100 +{
 101 +    static double laConfig = 0;
 102 +
 103 +    switch (action) {
 104 +    case RESERVE1: /* Check values for acceptability */
 105 +        if (var_val_type != ASN_OCTET_STR) {
 106 +            DEBUGMSGTL(("ucd-snmp/loadave",
 107 +                        "write to laConfig not ASN_OCTET_STR\n"));
 108 +            return SNMP_ERR_WRONGTYPE;
 109 +        }
 110 +        if (var_val_len > 8 || var_val_len <= 0) {
 111 +            DEBUGMSGTL(("ucd-snmp/loadave",
 112 +                        "write to laConfig: bad length\n"));
 113 +            return SNMP_ERR_WRONGLENGTH;
 114 +        }
 115 +
 116 +        if (laConfigSet < 0) {
 117 +            /*
 118 +             * The object is set in a read-only configuration file.
 119 +             */
 120 +            return SNMP_ERR_NOTWRITABLE;
 121 +        }
 122 +        break;
 123 +
 124 +    case RESERVE2: /* Allocate memory and similar resources */
 125 +        {
 126 +            u_char buf[8];
 127 +            int old_errno = errno;
 128 +            double val;
 129 +            char *endp;
 130 +
 131 +            strncpy(buf, var_val, var_val_len);
 132 +            buf[var_val_len] = '\0';
 133 +            val = strtod(buf, &endp);
 134 +
 135 +            if (errno == ERANGE || *endp != '\0' || val < 0 || val > 65536.00) {
 136 +                errno = old_errno;
 137 +                DEBUGMSGTL(("ucd-snmp/loadave",
 138 +                            "write to laConfig: invalid value\n"));
 139 +                return SNMP_ERR_WRONGVALUE;
 140 +            }
 141 +
 142 +            errno = old_errno;
 143 +
 144 +            laConfig = val;
 145 +        }
 146 +        break;
 147 +
 148 +    case COMMIT:
 149 +        {
 150 +            int idx = name[name_len - 1] - 1;
 151 +            maxload[idx] = laConfig;
 152 +            laConfigSet = 1;
 153 +        }
 154 +    }
 155 +
 156 +    return SNMP_ERR_NOERROR;
 157 +}
 158 +
 159  u_char         *
 160  var_extensible_loadave(struct variable * vp,
 161                         oid * name,
 162 @@ -328,6 +437,10 @@
 163      case MIBINDEX:
 164          long_ret = name[*length - 1];
 165          return ((u_char *) (&long_ret));
 166 +    case LOADMAXVAL:
 167 +        /* setup write method, but don't return yet */
 168 +        *write_method = write_laConfig;
 169 +        break;
 170      case ERRORNAME:
 171          sprintf(errmsg, "Load-%d", ((name[*length - 1] == 1) ? 1 :
 172                                      ((name[*length - 1] == 2) ? 5 : 15)));