Move functionality for parsing MIBs, SNMP into common files.

1 files changed, 381 insertions, 0 deletions

diff --git a/mib/mib-parser.c b/mib/mib-parser.c
new file mode 100644
index 0000000..f4b8c9d
--- /dev/null
+++ b/mib/mib-parser.c
@@ -0,0 +1,381 @@
+/*
+ * Copyright (c) 2005, Nate Nielsen
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *     * Redistributions of source code must retain the above
+ *       copyright notice, this list of conditions and the
+ *       following disclaimer.
+ *     * Redistributions in binary form must reproduce the
+ *       above copyright notice, this list of conditions and
+ *       the following disclaimer in the documentation and/or
+ *       other materials provided with the distribution.
+ *     * The names of contributors to this software may not be
+ *       used to endorse or promote products derived from this
+ *       software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ *
+ * CONTRIBUTORS
+ *  Nate Nielsen <nielsen@memberwebs.com>
+ *
+ */
+
+/*
+ * This file is not compiled on it's own. It's included into parse.c
+ * and provides compatibility definitions for making it work without
+ * the rest of net-snmp
+ */
+
+#include "usuals.h"
+#include <sys/types.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <syslog.h>
+#include <stdarg.h>
+#include <err.h>
+
+#include <bsnmp/asn1.h>
+#include <bsnmp/snmp.h>
+
+#include "parse.h"
+#include "mib-parser.h"
+
+/* Whether we print warnings when loading MIBs or not */
+const char* mib_directory = DEFAULT_MIB;
+int mib_warnings = 0;
+static int initialized = 0;
+
+/* -----------------------------------------------------------------------------
+ * DEFINITIONS
+ */
+
+#define FALSE 0
+#define TRUE 1
+
+/* No need to implement these */
+#define DEBUGMSGTL(x)
+#define set_function(tp)
+
+/* Just return the tree head */
+#define get_tree_head()     \
+    (tree_head)
+
+#define snmp_get_do_debugging()     (0)
+
+typedef u_long oid;
+
+#define NETSNMP_DS_LIBRARY_ID           0
+#define NETSNMP_DS_LIB_MIB_WARNINGS     1
+#define NETSNMP_DS_LIB_MIB_REPLACE      2
+#define NETSNMP_DS_LIB_SAVE_MIB_DESCRS  3
+#define NETSNMP_DS_LIB_MIB_ERRORS       4
+#define NETSNMP_DS_LIB_MIB_PARSE_LABEL  5
+#define NETSNMP_DS_LIB_MIB_COMMENT_TERM 6
+
+#define netsnmp_ds_get_boolean(d, v) \
+    netsnmp_ds_get_int(d, v)
+
+static int
+netsnmp_ds_get_int(int dummy, int var)
+{
+    switch(var)
+    {
+    case NETSNMP_DS_LIB_MIB_WARNINGS:
+        return mib_warnings;
+    case NETSNMP_DS_LIB_MIB_REPLACE:
+        return 0;
+    case NETSNMP_DS_LIB_SAVE_MIB_DESCRS:
+        return 0;
+    case NETSNMP_DS_LIB_MIB_PARSE_LABEL:
+        return 1;
+    case NETSNMP_DS_LIB_MIB_COMMENT_TERM:
+        return 0;
+    default:
+        return 0;
+    }
+}
+
+#define netsnmp_ds_set_int(a, b, c)
+#define netsnmp_ds_set_boolean(a, b, c)
+#define netsnmp_ds_toggle_boolean(a, b)
+
+static void
+snmp_log(int level, const char* msg, ...)
+{
+    va_list ap;
+
+    if(level >= LOG_WARNING && !mib_warnings)
+        return;
+
+    va_start(ap, msg);
+    vwarnx(msg, ap);
+    va_end(ap);
+}
+
+/* Only used to open files */
+static void
+snmp_log_perror(const char* file)
+{
+    warn("couldn't open file: %s", file);
+}
+
+#define SNMP_FREE(s)           do { if (s) { free((void *)s); s=NULL; } } while(0)
+
+/* -----------------------------------------------------------------------------
+ * RRDBOT GLUE CODE
+ */
+
+static void
+clear_tree_flags(struct tree *tp)
+{
+    for( ; tp; tp = tp->next_peer)
+    {
+        tp->reported = 0;
+        if(tp->child_list)
+            clear_tree_flags(tp->child_list);
+    }
+}
+
+void
+mib_init()
+{
+    if(initialized)
+        return;
+
+    init_mib_internals();
+    add_mibdir(mib_directory);
+    read_all_mibs();
+
+    warnx("loaded all MIB files");
+    initialized = 1;
+}
+
+mib_node
+mib_lookup(const char* match)
+{
+    extern struct tree *tree_head;
+    struct tree* mib;
+
+    ASSERT(initialized);
+
+    clear_tree_flags(tree_head);
+    mib = find_best_tree_node(match, NULL, NULL);
+    return (mib_node)mib;
+}
+
+int
+mib_subid(mib_node n, const char* name)
+{
+    struct tree *parent = (struct tree*)n;
+    struct tree *tp = NULL;
+
+    ASSERT(initialized);
+
+    for(tp = parent->child_list; tp; tp = tp->next_peer)
+    {
+        if(strcasecmp(name, tp->label) == 0)
+            return tp->subid;
+    }
+
+    return -1;
+}
+
+void
+mib_oid(mib_node n, struct asn_oid* oid)
+{
+    struct tree* mib = (struct tree*)n;
+    struct tree *tp = NULL;
+    int len;
+
+    ASSERT(mib);
+
+    /* Figure out where to start */
+    len = 0;
+    for(tp = mib; tp; tp = tp->parent)
+        len++;
+
+    oid->len = len;
+    for(tp = mib; tp; tp = tp->parent)
+        oid->subs[--len] = tp->subid;
+}
+
+mib_node
+mib_get_node(struct asn_oid* oid)
+{
+    extern struct tree *tree_head;
+    struct tree *tp = NULL;
+    asn_subid_t subid;
+    int i;
+
+    ASSERT(initialized);
+
+    for(i = 0, tp = tree_head; tp && i < oid->len;
+        i++, tp = tp ? tp->child_list : NULL)
+    {
+        subid = oid->subs[i];
+
+        while(tp && tp->subid != subid)
+            tp = tp->next_peer;
+
+        /* Did we find a match? */
+        if(tp && i == oid->len - 1)
+            break;
+    }
+
+    return tp;
+}
+
+void
+mib_uninit()
+{
+    if(initialized) {
+        unload_all_mibs();
+        warnx("unloaded all MIB files");
+    }
+    initialized = 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * INCLUDE parse.c
+ */
+
+#include "parse.c"
+
+/* -------------------------------------------------------------------------- */
+
+static int
+parse_mixed_mib(const char* mib, struct asn_oid* oid)
+{
+    mib_node n;
+    int ret = 0;
+    unsigned int sub;
+    char* next;
+    char* t;
+    char* copy;
+    char* src;
+
+    memset(oid, 0, sizeof(*oid));
+
+    copy = strdup(mib);
+    if(!copy)
+    {
+        errno = ENOMEM;
+        return -1;
+    }
+
+    for(src = copy; src && *src; src = next)
+    {
+        next = strchr(src, '.');
+        if(next)
+        {
+            *next = 0;
+            next++;
+        }
+
+        sub = strtoul(src, &t, 10);
+
+        /* An invalid number, try getting a named MIB */
+        if(*t || sub < 0)
+        {
+            /* Only initializes first time around */
+            mib_init();
+
+            /*
+             * If we haven't parsed anything yet, try a symbolic
+             * search for root
+             */
+
+            if(oid->len == 0)
+            {
+                n = mib_lookup(src);
+                if(n)
+                {
+                    /* That took care of it */
+                    mib_oid(n, oid);
+                    continue;
+                }
+            }
+
+            /* Try a by name search for sub item */
+            n = mib_get_node(oid);
+            if(n == NULL)
+                sub = -1;
+            else
+                sub = mib_subid(n, src);
+        }
+
+        /* Make sure this is a valid part */
+        if(sub < 0 || (oid->len == 0 && sub < 1) || sub >= ASN_MAXID)
+            ret = -1;
+
+        /* Too many parts */
+        if(oid->len > ASN_MAXOIDLEN)
+            ret = -1;
+
+        if(ret < 0)
+            break;
+
+        oid->subs[oid->len] = sub;
+        oid->len++;
+    }
+
+    free(copy);
+    return ret;
+}
+
+int
+mib_parse(const char* mib, struct snmp_value* value)
+{
+    int ret;
+    mib_node n;
+
+    value->syntax = SNMP_SYNTAX_NULL;
+    memset(&(value->v), 0, sizeof(value->v));
+
+    /* An initial dot */
+    if(*mib == '.')
+        mib++;
+
+    /*
+     * First try parsing a numeric OID. This will fall
+     * back to mixed mode MIB's if necassary. Allows us
+     * to avoid loading all the MIB files when not
+     * necessary
+     */
+
+    ret = parse_mixed_mib(mib, &(value->var));
+
+    /* Next try a symolic search */
+    if(ret == -1)
+    {
+        mib_init();
+
+        n = mib_lookup(mib);
+        if(n == NULL)
+            return -1;
+
+        mib_oid(n, &(value->var));
+        return 0;
+    }
+
+    return ret;
+}