--- /dev/null
+/**
+ * @file
+ * MIB tree access/construction functions.
+ */
+
+/*
+ * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ *
+ * Author: Christiaan Simons <christiaan.simons@axon.tv>
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/snmp_structs.h"
+#include "lwip/mem.h"
+
+/** .iso.org.dod.internet address prefix, @see snmp_iso_*() */
+const s32_t prefix[4] = {1, 3, 6, 1};
+
+#define NODE_STACK_SIZE (LWIP_SNMP_OBJ_ID_LEN)
+/** node stack entry (old news?) */
+struct nse
+{
+ /** right child */
+ struct mib_node* r_ptr;
+ /** right child identifier */
+ s32_t r_id;
+ /** right child next level */
+ u8_t r_nl;
+};
+static u8_t node_stack_cnt;
+static struct nse node_stack[NODE_STACK_SIZE];
+
+/**
+ * Pushes nse struct onto stack.
+ */
+static void
+push_node(struct nse* node)
+{
+ LWIP_ASSERT("node_stack_cnt < NODE_STACK_SIZE",node_stack_cnt < NODE_STACK_SIZE);
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("push_node() node=%p id=%"S32_F"\n",(void*)(node->r_ptr),node->r_id));
+ if (node_stack_cnt < NODE_STACK_SIZE)
+ {
+ node_stack[node_stack_cnt] = *node;
+ node_stack_cnt++;
+ }
+}
+
+/**
+ * Pops nse struct from stack.
+ */
+static void
+pop_node(struct nse* node)
+{
+ if (node_stack_cnt > 0)
+ {
+ node_stack_cnt--;
+ *node = node_stack[node_stack_cnt];
+ }
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("pop_node() node=%p id=%"S32_F"\n",(void *)(node->r_ptr),node->r_id));
+}
+
+/**
+ * Conversion from ifIndex to lwIP netif
+ * @param ifindex is a s32_t object sub-identifier
+ * @param netif points to returned netif struct pointer
+ */
+void
+snmp_ifindextonetif(s32_t ifindex, struct netif **netif)
+{
+ struct netif *nif = netif_list;
+ u16_t i, ifidx;
+
+ ifidx = ifindex - 1;
+ i = 0;
+ while ((nif != NULL) && (i < ifidx))
+ {
+ nif = nif->next;
+ i++;
+ }
+ *netif = nif;
+}
+
+/**
+ * Conversion from lwIP netif to ifIndex
+ * @param netif points to a netif struct
+ * @param ifidx points to s32_t object sub-identifier
+ */
+void
+snmp_netiftoifindex(struct netif *netif, s32_t *ifidx)
+{
+ struct netif *nif = netif_list;
+ u16_t i;
+
+ i = 0;
+ while (nif != netif)
+ {
+ nif = nif->next;
+ i++;
+ }
+ *ifidx = i+1;
+}
+
+/**
+ * Conversion from oid to lwIP ip_addr
+ * @param ident points to s32_t ident[4] input
+ * @param ip points to output struct
+ */
+void
+snmp_oidtoip(s32_t *ident, struct ip_addr *ip)
+{
+ u32_t ipa;
+
+ ipa = ident[0];
+ ipa <<= 8;
+ ipa |= ident[1];
+ ipa <<= 8;
+ ipa |= ident[2];
+ ipa <<= 8;
+ ipa |= ident[3];
+ ip->addr = ipa;
+}
+
+/**
+ * Conversion from lwIP ip_addr to oid
+ * @param ip points to input struct
+ * @param ident points to s32_t ident[4] output
+ */
+void
+snmp_iptooid(struct ip_addr *ip, s32_t *ident)
+{
+ u32_t ipa;
+
+ ipa = ip->addr;
+ ident[0] = (ipa >> 24) & 0xff;
+ ident[1] = (ipa >> 16) & 0xff;
+ ident[2] = (ipa >> 8) & 0xff;
+ ident[3] = ipa & 0xff;
+}
+
+struct mib_list_node *
+snmp_mib_ln_alloc(s32_t id)
+{
+ struct mib_list_node *ln;
+
+ ln = (struct mib_list_node *)mem_malloc(sizeof(struct mib_list_node));
+ if (ln != NULL)
+ {
+ ln->prev = NULL;
+ ln->next = NULL;
+ ln->objid = id;
+ ln->nptr = NULL;
+ }
+ return ln;
+}
+
+void
+snmp_mib_ln_free(struct mib_list_node *ln)
+{
+ mem_free(ln);
+}
+
+struct mib_list_rootnode *
+snmp_mib_lrn_alloc(void)
+{
+ struct mib_list_rootnode *lrn;
+
+ lrn = (struct mib_list_rootnode*)mem_malloc(sizeof(struct mib_list_rootnode));
+ if (lrn != NULL)
+ {
+ lrn->get_object_def = noleafs_get_object_def;
+ lrn->get_value = noleafs_get_value;
+ lrn->set_test = noleafs_set_test;
+ lrn->set_value = noleafs_set_value;
+ lrn->node_type = MIB_NODE_LR;
+ lrn->maxlength = 0;
+ lrn->head = NULL;
+ lrn->tail = NULL;
+ lrn->count = 0;
+ }
+ return lrn;
+}
+
+void
+snmp_mib_lrn_free(struct mib_list_rootnode *lrn)
+{
+ mem_free(lrn);
+}
+
+/**
+ * Inserts node in idx list in a sorted
+ * (ascending order) fashion and
+ * allocates the node if needed.
+ *
+ * @param rn points to the root node
+ * @param objid is the object sub identifier
+ * @param insn points to a pointer to the inserted node
+ * used for constructing the tree.
+ * @return -1 if failed, 1 if inserted, 2 if present.
+ */
+s8_t
+snmp_mib_node_insert(struct mib_list_rootnode *rn, s32_t objid, struct mib_list_node **insn)
+{
+ struct mib_list_node *nn;
+ s8_t insert;
+
+ LWIP_ASSERT("rn != NULL",rn != NULL);
+
+ /* -1 = malloc failure, 0 = not inserted, 1 = inserted, 2 = was present */
+ insert = 0;
+ if (rn->head == NULL)
+ {
+ /* empty list, add first node */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("alloc empty list objid==%"S32_F"\n",objid));
+ nn = snmp_mib_ln_alloc(objid);
+ if (nn != NULL)
+ {
+ rn->head = nn;
+ rn->tail = nn;
+ *insn = nn;
+ insert = 1;
+ }
+ else
+ {
+ insert = -1;
+ }
+ }
+ else
+ {
+ struct mib_list_node *n;
+ /* at least one node is present */
+ n = rn->head;
+ while ((n != NULL) && (insert == 0))
+ {
+ if (n->objid == objid)
+ {
+ /* node is already there */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("node already there objid==%"S32_F"\n",objid));
+ *insn = n;
+ insert = 2;
+ }
+ else if (n->objid < objid)
+ {
+ if (n->next == NULL)
+ {
+ /* alloc and insert at the tail */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("alloc ins tail objid==%"S32_F"\n",objid));
+ nn = snmp_mib_ln_alloc(objid);
+ if (nn != NULL)
+ {
+ nn->next = NULL;
+ nn->prev = n;
+ n->next = nn;
+ rn->tail = nn;
+ *insn = nn;
+ insert = 1;
+ }
+ else
+ {
+ /* insertion failure */
+ insert = -1;
+ }
+ }
+ else
+ {
+ /* there's more to explore: traverse list */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("traverse list\n"));
+ n = n->next;
+ }
+ }
+ else
+ {
+ /* n->objid > objid */
+ /* alloc and insert between n->prev and n */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("alloc ins n->prev, objid==%"S32_F", n\n",objid));
+ nn = snmp_mib_ln_alloc(objid);
+ if (nn != NULL)
+ {
+ if (n->prev == NULL)
+ {
+ /* insert at the head */
+ nn->next = n;
+ nn->prev = NULL;
+ rn->head = nn;
+ n->prev = nn;
+ }
+ else
+ {
+ /* insert in the middle */
+ nn->next = n;
+ nn->prev = n->prev;
+ n->prev->next = nn;
+ n->prev = nn;
+ }
+ *insn = nn;
+ insert = 1;
+ }
+ else
+ {
+ /* insertion failure */
+ insert = -1;
+ }
+ }
+ }
+ }
+ if (insert == 1)
+ {
+ rn->count += 1;
+ }
+ LWIP_ASSERT("insert != 0",insert != 0);
+ return insert;
+}
+
+/**
+ * Finds node in idx list and returns deletion mark.
+ *
+ * @param rn points to the root node
+ * @param objid is the object sub identifier
+ * @param fn returns pointer to found node
+ * @return 0 if not found, 1 if deletable,
+ * 2 can't delete (2 or more children), 3 not a list_node
+ */
+s8_t
+snmp_mib_node_find(struct mib_list_rootnode *rn, s32_t objid, struct mib_list_node **fn)
+{
+ s8_t fc;
+ struct mib_list_node *n;
+
+ LWIP_ASSERT("rn != NULL",rn != NULL);
+ n = rn->head;
+ while ((n != NULL) && (n->objid != objid))
+ {
+ n = n->next;
+ }
+ if (n == NULL)
+ {
+ fc = 0;
+ }
+ else if (n->nptr == NULL)
+ {
+ /* leaf, can delete node */
+ fc = 1;
+ }
+ else
+ {
+ struct mib_list_rootnode *r;
+
+ if (n->nptr->node_type == MIB_NODE_LR)
+ {
+ r = (struct mib_list_rootnode *)n->nptr;
+ if (r->count > 1)
+ {
+ /* can't delete node */
+ fc = 2;
+ }
+ else
+ {
+ /* count <= 1, can delete node */
+ fc = 1;
+ }
+ }
+ else
+ {
+ /* other node type */
+ fc = 3;
+ }
+ }
+ *fn = n;
+ return fc;
+}
+
+/**
+ * Removes node from idx list
+ * if it has a single child left.
+ *
+ * @param rn points to the root node
+ * @param n points to the node to delete
+ * @return the nptr to be freed by caller
+ */
+struct mib_list_rootnode *
+snmp_mib_node_delete(struct mib_list_rootnode *rn, struct mib_list_node *n)
+{
+ struct mib_list_rootnode *next;
+
+ LWIP_ASSERT("rn != NULL",rn != NULL);
+ LWIP_ASSERT("n != NULL",n != NULL);
+
+ /* caller must remove this sub-tree */
+ next = (struct mib_list_rootnode*)(n->nptr);
+ rn->count -= 1;
+
+ if (n == rn->head)
+ {
+ rn->head = n->next;
+ if (n->next != NULL)
+ {
+ /* not last node, new list begin */
+ n->next->prev = NULL;
+ }
+ }
+ else if (n == rn->tail)
+ {
+ rn->tail = n->prev;
+ if (n->prev != NULL)
+ {
+ /* not last node, new list end */
+ n->prev->next = NULL;
+ }
+ }
+ else
+ {
+ /* node must be in the middle */
+ n->prev->next = n->next;
+ n->next->prev = n->prev;
+ }
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("free list objid==%"S32_F"\n",n->objid));
+ snmp_mib_ln_free(n);
+ if (rn->count == 0)
+ {
+ rn->head = NULL;
+ rn->tail = NULL;
+ }
+ return next;
+}
+
+
+
+/**
+ * Searches tree for the supplied (scalar?) object identifier.
+ *
+ * @param node points to the root of the tree ('.internet')
+ * @param ident_len the length of the supplied object identifier
+ * @param ident points to the array of sub identifiers
+ * @param np points to the found object instance (rerurn)
+ * @return pointer to the requested parent (!) node if success, NULL otherwise
+ */
+struct mib_node *
+snmp_search_tree(struct mib_node *node, u8_t ident_len, s32_t *ident, struct snmp_name_ptr *np)
+{
+ u8_t node_type, ext_level;
+
+ ext_level = 0;
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("node==%p *ident==%"S32_F"\n",(void*)node,*ident));
+ while (node != NULL)
+ {
+ node_type = node->node_type;
+ if ((node_type == MIB_NODE_AR) || (node_type == MIB_NODE_RA))
+ {
+ struct mib_array_node *an;
+ u16_t i;
+
+ if (ident_len > 0)
+ {
+ /* array node (internal ROM or RAM, fixed length) */
+ an = (struct mib_array_node *)node;
+ i = 0;
+ while ((i < an->maxlength) && (an->objid[i] != *ident))
+ {
+ i++;
+ }
+ if (i < an->maxlength)
+ {
+ /* found it, if available proceed to child, otherwise inspect leaf */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("an->objid[%"U16_F"]==%"S32_F" *ident==%"S32_F"\n",i,an->objid[i],*ident));
+ if (an->nptr[i] == NULL)
+ {
+ /* a scalar leaf OR table,
+ inspect remaining instance number / table index */
+ np->ident_len = ident_len;
+ np->ident = ident;
+ return (struct mib_node*)an;
+ }
+ else
+ {
+ /* follow next child pointer */
+ ident++;
+ ident_len--;
+ node = an->nptr[i];
+ }
+ }
+ else
+ {
+ /* search failed, identifier mismatch (nosuchname) */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("an search failed *ident==%"S32_F"\n",*ident));
+ return NULL;
+ }
+ }
+ else
+ {
+ /* search failed, short object identifier (nosuchname) */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("an search failed, short object identifier\n"));
+ return NULL;
+ }
+ }
+ else if(node_type == MIB_NODE_LR)
+ {
+ struct mib_list_rootnode *lrn;
+ struct mib_list_node *ln;
+
+ if (ident_len > 0)
+ {
+ /* list root node (internal 'RAM', variable length) */
+ lrn = (struct mib_list_rootnode *)node;
+ ln = lrn->head;
+ /* iterate over list, head to tail */
+ while ((ln != NULL) && (ln->objid != *ident))
+ {
+ ln = ln->next;
+ }
+ if (ln != NULL)
+ {
+ /* found it, proceed to child */;
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("ln->objid==%"S32_F" *ident==%"S32_F"\n",ln->objid,*ident));
+ if (ln->nptr == NULL)
+ {
+ np->ident_len = ident_len;
+ np->ident = ident;
+ return (struct mib_node*)lrn;
+ }
+ else
+ {
+ /* follow next child pointer */
+ ident_len--;
+ ident++;
+ node = ln->nptr;
+ }
+ }
+ else
+ {
+ /* search failed */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("ln search failed *ident==%"S32_F"\n",*ident));
+ return NULL;
+ }
+ }
+ else
+ {
+ /* search failed, short object identifier (nosuchname) */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("ln search failed, short object identifier\n"));
+ return NULL;
+ }
+ }
+ else if(node_type == MIB_NODE_EX)
+ {
+ struct mib_external_node *en;
+ u16_t i, len;
+
+ if (ident_len > 0)
+ {
+ /* external node (addressing and access via functions) */
+ en = (struct mib_external_node *)node;
+
+ i = 0;
+ len = en->level_length(en->addr_inf,ext_level);
+ while ((i < len) && (en->ident_cmp(en->addr_inf,ext_level,i,*ident) != 0))
+ {
+ i++;
+ }
+ if (i < len)
+ {
+ s32_t debug_id;
+
+ en->get_objid(en->addr_inf,ext_level,i,&debug_id);
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("en->objid==%"S32_F" *ident==%"S32_F"\n",debug_id,*ident));
+ if ((ext_level + 1) == en->tree_levels)
+ {
+ np->ident_len = ident_len;
+ np->ident = ident;
+ return (struct mib_node*)en;
+ }
+ else
+ {
+ /* found it, proceed to child */
+ ident_len--;
+ ident++;
+ ext_level++;
+ }
+ }
+ else
+ {
+ /* search failed */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("en search failed *ident==%"S32_F"\n",*ident));
+ return NULL;
+ }
+ }
+ else
+ {
+ /* search failed, short object identifier (nosuchname) */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("en search failed, short object identifier\n"));
+ return NULL;
+ }
+ }
+ else if (node_type == MIB_NODE_SC)
+ {
+ mib_scalar_node *sn;
+
+ sn = (mib_scalar_node *)node;
+ if ((ident_len == 1) && (*ident == 0))
+ {
+ np->ident_len = ident_len;
+ np->ident = ident;
+ return (struct mib_node*)sn;
+ }
+ else
+ {
+ /* search failed, short object identifier (nosuchname) */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("search failed, invalid object identifier length\n"));
+ return NULL;
+ }
+ }
+ else
+ {
+ /* unknown node_type */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("search failed node_type %"U16_F" unkown\n",(u16_t)node_type));
+ return NULL;
+ }
+ }
+ /* done, found nothing */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("search failed node==%p\n",(void*)node));
+ return NULL;
+}
+
+/**
+ * Test table for presence of at least one table entry.
+ */
+static u8_t
+empty_table(struct mib_node *node)
+{
+ u8_t node_type;
+ u8_t empty = 0;
+
+ if (node != NULL)
+ {
+ node_type = node->node_type;
+ if (node_type == MIB_NODE_LR)
+ {
+ struct mib_list_rootnode *lrn;
+ lrn = (struct mib_list_rootnode *)node;
+ if ((lrn->count == 0) || (lrn->head == NULL))
+ {
+ empty = 1;
+ }
+ }
+ else if ((node_type == MIB_NODE_AR) || (node_type == MIB_NODE_RA))
+ {
+ struct mib_array_node *an;
+ an = (struct mib_array_node *)node;
+ if ((an->maxlength == 0) || (an->nptr == NULL))
+ {
+ empty = 1;
+ }
+ }
+ else if (node_type == MIB_NODE_EX)
+ {
+ struct mib_external_node *en;
+ en = (struct mib_external_node *)node;
+ if (en->tree_levels == 0)
+ {
+ empty = 1;
+ }
+ }
+ }
+ return empty;
+}
+
+/**
+ * Tree expansion.
+ */
+struct mib_node *
+snmp_expand_tree(struct mib_node *node, u8_t ident_len, s32_t *ident, struct snmp_obj_id *oidret)
+{
+ u8_t node_type, ext_level, climb_tree;
+
+ ext_level = 0;
+ /* reset node stack */
+ node_stack_cnt = 0;
+ while (node != NULL)
+ {
+ climb_tree = 0;
+ node_type = node->node_type;
+ if ((node_type == MIB_NODE_AR) || (node_type == MIB_NODE_RA))
+ {
+ struct mib_array_node *an;
+ u16_t i;
+
+ /* array node (internal ROM or RAM, fixed length) */
+ an = (struct mib_array_node *)node;
+ if (ident_len > 0)
+ {
+ i = 0;
+ while ((i < an->maxlength) && (an->objid[i] < *ident))
+ {
+ i++;
+ }
+ if (i < an->maxlength)
+ {
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("an->objid[%"U16_F"]==%"S32_F" *ident==%"S32_F"\n",i,an->objid[i],*ident));
+ /* add identifier to oidret */
+ oidret->id[oidret->len] = an->objid[i];
+ (oidret->len)++;
+
+ if (an->nptr[i] == NULL)
+ {
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("leaf node\n"));
+ /* leaf node (e.g. in a fixed size table) */
+ if (an->objid[i] > *ident)
+ {
+ return (struct mib_node*)an;
+ }
+ else if ((i + 1) < an->maxlength)
+ {
+ /* an->objid[i] == *ident */
+ (oidret->len)--;
+ oidret->id[oidret->len] = an->objid[i + 1];
+ (oidret->len)++;
+ return (struct mib_node*)an;
+ }
+ else
+ {
+ /* (i + 1) == an->maxlength */
+ (oidret->len)--;
+ climb_tree = 1;
+ }
+ }
+ else
+ {
+ u8_t j;
+ struct nse cur_node;
+
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("non-leaf node\n"));
+ /* non-leaf, store right child ptr and id */
+ j = i + 1;
+ while ((j < an->maxlength) && (empty_table(an->nptr[j])))
+ {
+ j++;
+ }
+ if (j < an->maxlength)
+ {
+ cur_node.r_ptr = an->nptr[j];
+ cur_node.r_id = an->objid[j];
+ cur_node.r_nl = 0;
+ }
+ else
+ {
+ cur_node.r_ptr = NULL;
+ }
+ push_node(&cur_node);
+ if (an->objid[i] == *ident)
+ {
+ ident_len--;
+ ident++;
+ }
+ else
+ {
+ /* an->objid[i] < *ident */
+ ident_len = 0;
+ }
+ /* follow next child pointer */
+ node = an->nptr[i];
+ }
+ }
+ else
+ {
+ /* i == an->maxlength */
+ climb_tree = 1;
+ }
+ }
+ else
+ {
+ u8_t j;
+ /* ident_len == 0, complete with leftmost '.thing' */
+ j = 0;
+ while ((j < an->maxlength) && empty_table(an->nptr[j]))
+ {
+ j++;
+ }
+ if (j < an->maxlength)
+ {
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("left an->objid[j]==%"S32_F"\n",an->objid[j]));
+ oidret->id[oidret->len] = an->objid[j];
+ (oidret->len)++;
+ if (an->nptr[j] == NULL)
+ {
+ /* leaf node */
+ return (struct mib_node*)an;
+ }
+ else
+ {
+ /* no leaf, continue */
+ node = an->nptr[j];
+ }
+ }
+ else
+ {
+ /* j == an->maxlength */
+ climb_tree = 1;
+ }
+ }
+ }
+ else if(node_type == MIB_NODE_LR)
+ {
+ struct mib_list_rootnode *lrn;
+ struct mib_list_node *ln;
+
+ /* list root node (internal 'RAM', variable length) */
+ lrn = (struct mib_list_rootnode *)node;
+ if (ident_len > 0)
+ {
+ ln = lrn->head;
+ /* iterate over list, head to tail */
+ while ((ln != NULL) && (ln->objid < *ident))
+ {
+ ln = ln->next;
+ }
+ if (ln != NULL)
+ {
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("ln->objid==%"S32_F" *ident==%"S32_F"\n",ln->objid,*ident));
+ oidret->id[oidret->len] = ln->objid;
+ (oidret->len)++;
+ if (ln->nptr == NULL)
+ {
+ /* leaf node */
+ if (ln->objid > *ident)
+ {
+ return (struct mib_node*)lrn;
+ }
+ else if (ln->next != NULL)
+ {
+ /* ln->objid == *ident */
+ (oidret->len)--;
+ oidret->id[oidret->len] = ln->next->objid;
+ (oidret->len)++;
+ return (struct mib_node*)lrn;
+ }
+ else
+ {
+ /* ln->next == NULL */
+ (oidret->len)--;
+ climb_tree = 1;
+ }
+ }
+ else
+ {
+ struct mib_list_node *jn;
+ struct nse cur_node;
+
+ /* non-leaf, store right child ptr and id */
+ jn = ln->next;
+ while ((jn != NULL) && empty_table(jn->nptr))
+ {
+ jn = jn->next;
+ }
+ if (jn != NULL)
+ {
+ cur_node.r_ptr = jn->nptr;
+ cur_node.r_id = jn->objid;
+ cur_node.r_nl = 0;
+ }
+ else
+ {
+ cur_node.r_ptr = NULL;
+ }
+ push_node(&cur_node);
+ if (ln->objid == *ident)
+ {
+ ident_len--;
+ ident++;
+ }
+ else
+ {
+ /* ln->objid < *ident */
+ ident_len = 0;
+ }
+ /* follow next child pointer */
+ node = ln->nptr;
+ }
+
+ }
+ else
+ {
+ /* ln == NULL */
+ climb_tree = 1;
+ }
+ }
+ else
+ {
+ struct mib_list_node *jn;
+ /* ident_len == 0, complete with leftmost '.thing' */
+ jn = lrn->head;
+ while ((jn != NULL) && empty_table(jn->nptr))
+ {
+ jn = jn->next;
+ }
+ if (jn != NULL)
+ {
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("left jn->objid==%"S32_F"\n",jn->objid));
+ oidret->id[oidret->len] = jn->objid;
+ (oidret->len)++;
+ if (jn->nptr == NULL)
+ {
+ /* leaf node */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("jn->nptr == NULL\n"));
+ return (struct mib_node*)lrn;
+ }
+ else
+ {
+ /* no leaf, continue */
+ node = jn->nptr;
+ }
+ }
+ else
+ {
+ /* jn == NULL */
+ climb_tree = 1;
+ }
+ }
+ }
+ else if(node_type == MIB_NODE_EX)
+ {
+ struct mib_external_node *en;
+ s32_t ex_id;
+
+ /* external node (addressing and access via functions) */
+ en = (struct mib_external_node *)node;
+ if (ident_len > 0)
+ {
+ u16_t i, len;
+
+ i = 0;
+ len = en->level_length(en->addr_inf,ext_level);
+ while ((i < len) && (en->ident_cmp(en->addr_inf,ext_level,i,*ident) < 0))
+ {
+ i++;
+ }
+ if (i < len)
+ {
+ /* add identifier to oidret */
+ en->get_objid(en->addr_inf,ext_level,i,&ex_id);
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("en->objid[%"U16_F"]==%"S32_F" *ident==%"S32_F"\n",i,ex_id,*ident));
+ oidret->id[oidret->len] = ex_id;
+ (oidret->len)++;
+
+ if ((ext_level + 1) == en->tree_levels)
+ {
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("leaf node\n"));
+ /* leaf node */
+ if (ex_id > *ident)
+ {
+ return (struct mib_node*)en;
+ }
+ else if ((i + 1) < len)
+ {
+ /* ex_id == *ident */
+ en->get_objid(en->addr_inf,ext_level,i + 1,&ex_id);
+ (oidret->len)--;
+ oidret->id[oidret->len] = ex_id;
+ (oidret->len)++;
+ return (struct mib_node*)en;
+ }
+ else
+ {
+ /* (i + 1) == len */
+ (oidret->len)--;
+ climb_tree = 1;
+ }
+ }
+ else
+ {
+ u8_t j;
+ struct nse cur_node;
+
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("non-leaf node\n"));
+ /* non-leaf, store right child ptr and id */
+ j = i + 1;
+ if (j < len)
+ {
+ /* right node is the current external node */
+ cur_node.r_ptr = node;
+ en->get_objid(en->addr_inf,ext_level,j,&cur_node.r_id);
+ cur_node.r_nl = ext_level + 1;
+ }
+ else
+ {
+ cur_node.r_ptr = NULL;
+ }
+ push_node(&cur_node);
+ if (en->ident_cmp(en->addr_inf,ext_level,i,*ident) == 0)
+ {
+ ident_len--;
+ ident++;
+ }
+ else
+ {
+ /* external id < *ident */
+ ident_len = 0;
+ }
+ /* proceed to child */
+ ext_level++;
+ }
+ }
+ else
+ {
+ /* i == len (en->level_len()) */
+ climb_tree = 1;
+ }
+ }
+ else
+ {
+ /* ident_len == 0, complete with leftmost '.thing' */
+ en->get_objid(en->addr_inf,ext_level,0,&ex_id);
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("left en->objid==%"S32_F"\n",ex_id));
+ oidret->id[oidret->len] = ex_id;
+ (oidret->len)++;
+ if ((ext_level + 1) == en->tree_levels)
+ {
+ /* leaf node */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("(ext_level + 1) == en->tree_levels\n"));
+ return (struct mib_node*)en;
+ }
+ else
+ {
+ /* no leaf, proceed to child */
+ ext_level++;
+ }
+ }
+ }
+ else if(node_type == MIB_NODE_SC)
+ {
+ mib_scalar_node *sn;
+
+ /* scalar node */
+ sn = (mib_scalar_node *)node;
+ if (ident_len > 0)
+ {
+ /* at .0 */
+ climb_tree = 1;
+ }
+ else
+ {
+ /* ident_len == 0, complete object identifier */
+ oidret->id[oidret->len] = 0;
+ (oidret->len)++;
+ /* leaf node */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("completed scalar leaf\n"));
+ return (struct mib_node*)sn;
+ }
+ }
+ else
+ {
+ /* unknown/unhandled node_type */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("expand failed node_type %"U16_F" unkown\n",(u16_t)node_type));
+ return NULL;
+ }
+
+ if (climb_tree)
+ {
+ struct nse child;
+
+ /* find right child ptr */
+ child.r_ptr = NULL;
+ child.r_id = 0;
+ child.r_nl = 0;
+ while ((node_stack_cnt > 0) && (child.r_ptr == NULL))
+ {
+ pop_node(&child);
+ /* trim returned oid */
+ (oidret->len)--;
+ }
+ if (child.r_ptr != NULL)
+ {
+ /* incoming ident is useless beyond this point */
+ ident_len = 0;
+ oidret->id[oidret->len] = child.r_id;
+ oidret->len++;
+ node = child.r_ptr;
+ ext_level = child.r_nl;
+ }
+ else
+ {
+ /* tree ends here ... */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("expand failed, tree ends here\n"));
+ return NULL;
+ }
+ }
+ }
+ /* done, found nothing */
+ LWIP_DEBUGF(SNMP_MIB_DEBUG,("expand failed node==%p\n",(void*)node));
+ return NULL;
+}
+
+/**
+ * Test object identifier for the iso.org.dod.internet prefix.
+ *
+ * @param ident_len the length of the supplied object identifier
+ * @param ident points to the array of sub identifiers
+ * @return 1 if it matches, 0 otherwise
+ */
+u8_t
+snmp_iso_prefix_tst(u8_t ident_len, s32_t *ident)
+{
+ if ((ident_len > 3) &&
+ (ident[0] == 1) && (ident[1] == 3) &&
+ (ident[2] == 6) && (ident[3] == 1))
+ {
+ return 1;
+ }
+ else
+ {
+ return 0;
+ }
+}
+
+/**
+ * Expands object identifier to the iso.org.dod.internet
+ * prefix for use in getnext operation.
+ *
+ * @param ident_len the length of the supplied object identifier
+ * @param ident points to the array of sub identifiers
+ * @param oidret points to returned expanded object identifier
+ * @return 1 if it matches, 0 otherwise
+ *
+ * @note ident_len 0 is allowed, expanding to the first known object id!!
+ */
+u8_t
+snmp_iso_prefix_expand(u8_t ident_len, s32_t *ident, struct snmp_obj_id *oidret)
+{
+ const s32_t *prefix_ptr;
+ s32_t *ret_ptr;
+ u8_t i;
+
+ i = 0;
+ prefix_ptr = &prefix[0];
+ ret_ptr = &oidret->id[0];
+ ident_len = ((ident_len < 4)?ident_len:4);
+ while ((i < ident_len) && ((*ident) <= (*prefix_ptr)))
+ {
+ *ret_ptr++ = *prefix_ptr++;
+ ident++;
+ i++;
+ }
+ if (i == ident_len)
+ {
+ /* match, complete missing bits */
+ while (i < 4)
+ {
+ *ret_ptr++ = *prefix_ptr++;
+ i++;
+ }
+ oidret->len = i;
+ return 1;
+ }
+ else
+ {
+ /* i != ident_len */
+ return 0;
+ }
+}
+
+#endif /* LWIP_SNMP */
