Used in Live Traffic Update Nokia LCD Display Project
Fork of NetServices by
Diff: lwip/core/snmp/mib_structs.c
- Revision:
- 0:ac1725ba162c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/lwip/core/snmp/mib_structs.c Tue Nov 09 20:54:15 2010 +0000 @@ -0,0 +1,1174 @@ +/** + * @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/memp.h" +#include "lwip/netif.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; + s32_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 != NULL) && (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, ip_addr_t *ip) +{ + IP4_ADDR(ip, ident[0], ident[1], ident[2], ident[3]); +} + +/** + * 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(ip_addr_t *ip, s32_t *ident) +{ + ident[0] = ip4_addr1(ip); + ident[1] = ip4_addr2(ip); + ident[2] = ip4_addr3(ip); + ident[3] = ip4_addr4(ip); +} + +struct mib_list_node * +snmp_mib_ln_alloc(s32_t id) +{ + struct mib_list_node *ln; + + ln = (struct mib_list_node *)memp_malloc(MEMP_SNMP_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) +{ + memp_free(MEMP_SNMP_NODE, ln); +} + +struct mib_list_rootnode * +snmp_mib_lrn_alloc(void) +{ + struct mib_list_rootnode *lrn; + + lrn = (struct mib_list_rootnode*)memp_malloc(MEMP_SNMP_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) +{ + memp_free(MEMP_SNMP_ROOTNODE, 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 (return) + * @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 */ + LWIP_ASSERT("i < 0xff", i < 0xff); + j = (u8_t)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 */ + LWIP_ASSERT("i < 0xff", i < 0xff); + j = (u8_t)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 */