Lorcan Smith
SNMP agent attached to SPI slave
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msg_in.c
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00001 /***************************************************************************** 00002 * Copyright SEEC Ltd 00003 * File: msg_in.c 00004 * Reference: A3600-SRC-msg_in 00005 * Content: Parse incoming SNMP messages 00006 * Version: 0.3 00007 * System: mbed gnu compiler 00008 * Target Hardware: mbed LPC1768 00009 * Amendment Record: 00010 * Author: L. Smith for all versions unless otherwise specified 00011 * Initial release 00012 * 0.1 21/11/11: L. Smith 00013 Derived from msg_in.c by Christiaan Simons <christiaan.simons@axon.tv> 00014 * 0.2 26/04/12: L. Smith 00015 Increase snmp_publiccommunity[7] to [21] and allow this to be set from file 00016 * 0.3 10/05/12: L. Smith 00017 Don't snmp_coldstart_trap() as outgoing interface not yet configured 00018 *******************************************************************************/ 00019 /** 00020 * @file 00021 * SNMP input message processing (RFC1157). 00022 */ 00023 00024 /* 00025 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands. 00026 * All rights reserved. 00027 * 00028 * Redistribution and use in source and binary forms, with or without modification, 00029 * are permitted provided that the following conditions are met: 00030 * 00031 * 1. Redistributions of source code must retain the above copyright notice, 00032 * this list of conditions and the following disclaimer. 00033 * 2. Redistributions in binary form must reproduce the above copyright notice, 00034 * this list of conditions and the following disclaimer in the documentation 00035 * and/or other materials provided with the distribution. 00036 * 3. The name of the author may not be used to endorse or promote products 00037 * derived from this software without specific prior written permission. 00038 * 00039 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 00040 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 00041 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 00042 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 00043 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 00044 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 00045 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 00046 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 00047 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 00048 * OF SUCH DAMAGE. 00049 * 00050 * Author: Christiaan Simons <christiaan.simons@axon.tv> 00051 0.1 22/12/11 LS Add blink_led to show comms activity 00052 */ 00053 00054 #include "lwip/opt.h" 00055 00056 #include "ipaddr.h" 00057 #include "IO_file.h" 00058 00059 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */ 00060 00061 #include "lwip/snmp.h" 00062 #include "lwip/snmp_asn1.h" 00063 #include "lwip/snmp_msg.h" 00064 #include "lwip/snmp_structs.h" 00065 #include "lwip/ip_addr.h" 00066 #include "lwip/memp.h" 00067 #include "lwip/udp.h" 00068 #include "lwip/stats.h" 00069 00070 #include <string.h> 00071 #include <stdio.h> 00072 00073 /* public (non-static) constants */ 00074 /** SNMP v1 == 0 */ 00075 const s32_t snmp_version = 0; 00076 /** default SNMP community string 00077 const char snmp_publiccommunity[7] = "public"; v0.2: */ 00078 char snmp_publiccommunity[MAX_COMMUNITY] = "public"; // v0.2: Allow changes up to 20 characters 00079 00080 /* statically allocated buffers for SNMP_CONCURRENT_REQUESTS */ 00081 struct snmp_msg_pstat msg_input_list[SNMP_CONCURRENT_REQUESTS]; 00082 /* UDP Protocol Control Block */ 00083 struct udp_pcb *snmp1_pcb; 00084 00085 static void snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port); 00086 static err_t snmp_pdu_header_check(struct pbuf *p, u16_t ofs, u16_t pdu_len, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat); 00087 static err_t snmp_pdu_dec_varbindlist(struct pbuf *p, u16_t ofs, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat); 00088 00089 00090 /** 00091 * Starts SNMP Agent. 00092 * Allocates UDP pcb and binds it to IP_ADDR_ANY port 161. 00093 */ 00094 void 00095 snmp_init(void) 00096 { 00097 struct snmp_msg_pstat *msg_ps; 00098 u8_t i; 00099 00100 snmp1_pcb = udp_new(); 00101 if (snmp1_pcb != NULL) 00102 { 00103 // printf("\r\nIn snmp_init: snmp1_pcb created\r\n"); 00104 udp_recv(snmp1_pcb, snmp_recv, (void *)SNMP_IN_PORT); 00105 // udp_bind(snmp1_pcb, (ip_addr_t *)&mip, SNMP_IN_PORT); 00106 udp_bind(snmp1_pcb, IP_ADDR_ANY, SNMP_IN_PORT); 00107 } 00108 msg_ps = &msg_input_list[0]; 00109 for (i=0; i<SNMP_CONCURRENT_REQUESTS; i++) 00110 { 00111 msg_ps->state = SNMP_MSG_EMPTY; 00112 msg_ps->error_index = 0; 00113 msg_ps->error_status = SNMP_ES_NOERROR; 00114 msg_ps++; 00115 } 00116 trap_msg.pcb = snmp1_pcb; 00117 00118 #ifdef SNMP_PRIVATE_MIB_INIT 00119 /* If defined, rhis must be a function-like define to initialize the 00120 * private MIB after the stack has been initialized. 00121 * The private MIB can also be initialized in tcpip_callback (or after 00122 * the stack is initialized), this define is only for convenience. */ 00123 SNMP_PRIVATE_MIB_INIT(); 00124 #endif /* SNMP_PRIVATE_MIB_INIT */ 00125 00126 /* The coldstart trap will only be output 00127 if our outgoing interface is up & configured 00128 snmp_coldstart_trap(); v0.3: outgoing interface not yet configured */ 00129 } 00130 00131 static void 00132 snmp_error_response(struct snmp_msg_pstat *msg_ps, u8_t error) 00133 { 00134 snmp_varbind_list_free(&msg_ps->outvb); 00135 printf("\r\nsnmp_error_response: %d\r\n", error); 00136 msg_ps->outvb = msg_ps->invb; 00137 msg_ps->invb.head = NULL; 00138 msg_ps->invb.tail = NULL; 00139 msg_ps->invb.count = 0; 00140 msg_ps->error_status = error; 00141 msg_ps->error_index = 1 + msg_ps->vb_idx; 00142 snmp_send_response(msg_ps); 00143 snmp_varbind_list_free(&msg_ps->outvb); 00144 msg_ps->state = SNMP_MSG_EMPTY; 00145 } 00146 00147 static void 00148 snmp_ok_response(struct snmp_msg_pstat *msg_ps) 00149 { 00150 err_t err_ret; 00151 00152 err_ret = snmp_send_response(msg_ps); 00153 if (err_ret == ERR_MEM) 00154 { 00155 /* serious memory problem, can't return tooBig */ 00156 printf("snmp_ok_response: serious memory problem, can't return tooBig"); 00157 } 00158 else 00159 { 00160 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("\r\nsnmp_msg_event = %"S32_F"\n",msg_ps->error_status)); 00161 } 00162 /* free varbinds (if available) */ 00163 snmp_varbind_list_free(&msg_ps->invb); 00164 snmp_varbind_list_free(&msg_ps->outvb); 00165 msg_ps->state = SNMP_MSG_EMPTY; 00166 } 00167 00168 /** 00169 * Service an internal or external event for SNMP GET. 00170 * 00171 * @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) 00172 * @param msg_ps points to the assosicated message process state 00173 */ 00174 static void 00175 snmp_msg_get_event(u8_t request_id, struct snmp_msg_pstat *msg_ps) 00176 { 00177 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_get_event: msg_ps->state = %"U16_F"\n",(u16_t)msg_ps->state)); 00178 00179 if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF) 00180 { 00181 struct mib_external_node *en; 00182 struct snmp_name_ptr np; 00183 00184 /* get_object_def() answer*/ 00185 en = msg_ps->ext_mib_node; 00186 np = msg_ps->ext_name_ptr; 00187 00188 /* translate answer into a known lifeform */ 00189 en->get_object_def_a(request_id, np.ident_len, np.ident, &msg_ps->ext_object_def); 00190 if ((msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) && 00191 (msg_ps->ext_object_def.access & MIB_ACCESS_READ)) 00192 { 00193 printf("snmp_msg_get_event found"); 00194 msg_ps->state = SNMP_MSG_EXTERNAL_GET_VALUE; 00195 en->get_value_q(request_id, &msg_ps->ext_object_def); 00196 } 00197 else 00198 { 00199 en->get_object_def_pc(request_id, np.ident_len, np.ident); 00200 /* search failed, object id points to unknown object (nosuchname) */ 00201 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00202 } 00203 } 00204 else if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_VALUE) 00205 { 00206 struct mib_external_node *en; 00207 struct snmp_varbind *vb; 00208 00209 /* get_value() answer */ 00210 en = msg_ps->ext_mib_node; 00211 00212 /* allocate output varbind */ 00213 vb = (struct snmp_varbind *)memp_malloc(MEMP_SNMP_VARBIND); 00214 LWIP_ASSERT("vb != NULL",vb != NULL); 00215 if (vb != NULL) 00216 { 00217 vb->next = NULL; 00218 vb->prev = NULL; 00219 00220 /* move name from invb to outvb */ 00221 vb->ident = msg_ps->vb_ptr->ident; 00222 vb->ident_len = msg_ps->vb_ptr->ident_len; 00223 /* ensure this memory is refereced once only */ 00224 msg_ps->vb_ptr->ident = NULL; 00225 msg_ps->vb_ptr->ident_len = 0; 00226 00227 vb->value_type = msg_ps->ext_object_def.asn_type; 00228 LWIP_ASSERT("invalid length", msg_ps->ext_object_def.v_len <= 0xff); 00229 vb->value_len = (u8_t)msg_ps->ext_object_def.v_len; 00230 if (vb->value_len > 0) 00231 { 00232 LWIP_ASSERT("SNMP_MAX_OCTET_STRING_LEN is configured too low", vb->value_len <= SNMP_MAX_VALUE_SIZE); 00233 vb->value = memp_malloc(MEMP_SNMP_VALUE); 00234 LWIP_ASSERT("vb->value != NULL",vb->value != NULL); 00235 if (vb->value != NULL) 00236 { 00237 en->get_value_a(request_id, &msg_ps->ext_object_def, vb->value_len, vb->value); 00238 snmp_varbind_tail_add(&msg_ps->outvb, vb); 00239 /* search again (if vb_idx < msg_ps->invb.count) */ 00240 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00241 msg_ps->vb_idx += 1; 00242 } 00243 else 00244 { 00245 en->get_value_pc(request_id, &msg_ps->ext_object_def); 00246 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_event: no variable space\n")); 00247 msg_ps->vb_ptr->ident = vb->ident; 00248 msg_ps->vb_ptr->ident_len = vb->ident_len; 00249 memp_free(MEMP_SNMP_VARBIND, vb); 00250 snmp_error_response(msg_ps,SNMP_ES_TOOBIG); 00251 } 00252 } 00253 else 00254 { 00255 /* vb->value_len == 0, empty value (e.g. empty string) */ 00256 en->get_value_a(request_id, &msg_ps->ext_object_def, 0, NULL); 00257 vb->value = NULL; 00258 snmp_varbind_tail_add(&msg_ps->outvb, vb); 00259 /* search again (if vb_idx < msg_ps->invb.count) */ 00260 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00261 msg_ps->vb_idx += 1; 00262 } 00263 } 00264 else 00265 { 00266 en->get_value_pc(request_id, &msg_ps->ext_object_def); 00267 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_event: no outvb space\n")); 00268 snmp_error_response(msg_ps,SNMP_ES_TOOBIG); 00269 } 00270 } 00271 00272 //printf("\r\nsnmp_msg_get_event: msg_ps->invb.count = %d, msg_ps->vb_idx = %d\r\n", msg_ps->invb.count, msg_ps->vb_idx); 00273 while ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && 00274 (msg_ps->vb_idx < msg_ps->invb.count)) 00275 { 00276 struct mib_node *mn; 00277 struct snmp_name_ptr np; 00278 00279 if (msg_ps->vb_idx == 0) 00280 { 00281 msg_ps->vb_ptr = msg_ps->invb.head; 00282 } 00283 else 00284 { 00285 msg_ps->vb_ptr = msg_ps->vb_ptr->next; 00286 } 00287 /** test object identifier for .iso.org.dod.internet prefix */ 00288 if (snmp_iso_prefix_tst(msg_ps->vb_ptr->ident_len, msg_ps->vb_ptr->ident)) 00289 { 00290 mn = snmp_search_tree((struct mib_node*)&internet, msg_ps->vb_ptr->ident_len - 4, 00291 msg_ps->vb_ptr->ident + 4, &np); 00292 if (mn != NULL) 00293 { 00294 //printf("snmp_msg_get_event: mn->node_type = %d\r\n", mn->node_type); 00295 if (mn->node_type == MIB_NODE_EX) 00296 { 00297 /* external object */ 00298 struct mib_external_node *en = (struct mib_external_node*)mn; 00299 00300 msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF; 00301 /* save en && args in msg_ps!! */ 00302 msg_ps->ext_mib_node = en; 00303 msg_ps->ext_name_ptr = np; 00304 00305 en->get_object_def_q(en->addr_inf, request_id, np.ident_len, np.ident); 00306 } 00307 else 00308 { 00309 /* internal object */ 00310 struct obj_def object_def; 00311 00312 msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF; 00313 printf("\r\nsnmp_msg_get_event: mn->node_type = %d, msg_ps->state %d\r\n", mn->node_type, msg_ps->state); 00314 mn->get_object_def(np.ident_len, np.ident, &object_def); 00315 if ((object_def.instance != MIB_OBJECT_NONE) && 00316 (object_def.access & MIB_ACCESS_READ)) 00317 { 00318 mn = mn; 00319 } 00320 else 00321 { 00322 /* search failed, object id points to unknown object (nosuchname) */ 00323 mn = NULL; 00324 } 00325 if (mn != NULL) 00326 { 00327 struct snmp_varbind *vb; 00328 00329 msg_ps->state = SNMP_MSG_INTERNAL_GET_VALUE; 00330 /* allocate output varbind */ 00331 vb = (struct snmp_varbind *)memp_malloc(MEMP_SNMP_VARBIND); 00332 LWIP_ASSERT("vb != NULL",vb != NULL); 00333 if (vb != NULL) 00334 { 00335 vb->next = NULL; 00336 vb->prev = NULL; 00337 00338 /* move name from invb to outvb */ 00339 vb->ident = msg_ps->vb_ptr->ident; 00340 vb->ident_len = msg_ps->vb_ptr->ident_len; 00341 /* ensure this memory is referenced once only */ 00342 msg_ps->vb_ptr->ident = NULL; 00343 msg_ps->vb_ptr->ident_len = 0; 00344 00345 vb->value_type = object_def.asn_type; 00346 LWIP_ASSERT("invalid length", object_def.v_len <= 0xff); 00347 vb->value_len = (u8_t)object_def.v_len; 00348 printf("\r\nsnmp_msg_get_event: vb->value_type = %d,vb->value_len = %d\r\n", vb->value_type, vb->value_len); 00349 if (vb->value_len > 0) 00350 { 00351 LWIP_ASSERT("SNMP_MAX_OCTET_STRING_LEN is configured too low", 00352 vb->value_len <= SNMP_MAX_VALUE_SIZE); 00353 vb->value = memp_malloc(MEMP_SNMP_VALUE); 00354 LWIP_ASSERT("vb->value != NULL",vb->value != NULL); 00355 if (vb->value != NULL) 00356 { 00357 mn->get_value(&object_def, vb->value_len, vb->value); 00358 snmp_varbind_tail_add(&msg_ps->outvb, vb); 00359 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00360 msg_ps->vb_idx += 1; 00361 } 00362 else 00363 { 00364 printf("\r\nsnmp_msg_get_event: memp_malloc failed\r\n"); 00365 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_event: couldn't allocate variable space\n")); 00366 msg_ps->vb_ptr->ident = vb->ident; 00367 msg_ps->vb_ptr->ident_len = vb->ident_len; 00368 memp_free(MEMP_SNMP_VARBIND, vb); 00369 snmp_error_response(msg_ps,SNMP_ES_TOOBIG); 00370 } 00371 } 00372 else 00373 { 00374 /* vb->value_len == 0, empty value (e.g. empty string) */ 00375 vb->value = NULL; 00376 snmp_varbind_tail_add(&msg_ps->outvb, vb); 00377 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00378 msg_ps->vb_idx += 1; 00379 } 00380 } 00381 else 00382 { 00383 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_event: couldn't allocate outvb space\n")); 00384 snmp_error_response(msg_ps,SNMP_ES_TOOBIG); 00385 } 00386 } 00387 } 00388 } 00389 } 00390 else 00391 { 00392 mn = NULL; 00393 } 00394 if (mn == NULL) 00395 { 00396 /* mn == NULL, noSuchName */ 00397 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00398 } 00399 } 00400 if ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && 00401 (msg_ps->vb_idx == msg_ps->invb.count)) 00402 { 00403 snmp_ok_response(msg_ps); 00404 } 00405 } 00406 00407 /** 00408 * Service an internal or external event for SNMP GETNEXT. 00409 * 00410 * @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) 00411 * @param msg_ps points to the assosicated message process state 00412 */ 00413 static void 00414 snmp_msg_getnext_event(u8_t request_id, struct snmp_msg_pstat *msg_ps) 00415 { 00416 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_getnext_event: msg_ps->state==%"U16_F"\n",(u16_t)msg_ps->state)); 00417 if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF) 00418 { 00419 struct mib_external_node *en; 00420 00421 /* get_object_def() answer*/ 00422 en = msg_ps->ext_mib_node; 00423 00424 //printf("snmp_msg_getnext_event DEF id %d\r\n", msg_ps->ext_oid.id[msg_ps->ext_oid.len - 1]); 00425 /* translate answer into a known lifeform */ 00426 en->get_object_def_a(request_id, 1, &msg_ps->ext_oid.id[msg_ps->ext_oid.len - 1], &msg_ps->ext_object_def); 00427 if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) 00428 { 00429 msg_ps->state = SNMP_MSG_EXTERNAL_GET_VALUE; 00430 en->get_value_q(request_id, &msg_ps->ext_object_def); 00431 } 00432 else 00433 { 00434 en->get_object_def_pc(request_id, 1, &msg_ps->ext_oid.id[msg_ps->ext_oid.len - 1]); 00435 /* search failed, object id points to unknown object (nosuchname) */ 00436 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00437 } 00438 } 00439 else if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_VALUE) 00440 { 00441 struct mib_external_node *en; 00442 struct snmp_varbind *vb; 00443 00444 //printf("snmp_msg_getnext_event VAL type %d\r\n", msg_ps->ext_object_def.asn_type); 00445 /* get_value() answer */ 00446 en = msg_ps->ext_mib_node; 00447 00448 LWIP_ASSERT("invalid length", msg_ps->ext_object_def.v_len <= 0xff); 00449 vb = snmp_varbind_alloc(&msg_ps->ext_oid, 00450 msg_ps->ext_object_def.asn_type, 00451 (u8_t)msg_ps->ext_object_def.v_len); 00452 if (vb != NULL) 00453 { 00454 en->get_value_a(request_id, &msg_ps->ext_object_def, vb->value_len, vb->value); 00455 snmp_varbind_tail_add(&msg_ps->outvb, vb); 00456 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00457 msg_ps->vb_idx += 1; 00458 } 00459 else 00460 { 00461 en->get_value_pc(request_id, &msg_ps->ext_object_def); 00462 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_getnext_event: couldn't allocate outvb space\n")); 00463 snmp_error_response(msg_ps,SNMP_ES_TOOBIG); 00464 } 00465 } 00466 00467 while ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && 00468 (msg_ps->vb_idx < msg_ps->invb.count)) 00469 { 00470 struct mib_node *mn; 00471 struct snmp_obj_id oid; 00472 00473 if (msg_ps->vb_idx == 0) 00474 { 00475 msg_ps->vb_ptr = msg_ps->invb.head; 00476 } 00477 else 00478 { 00479 msg_ps->vb_ptr = msg_ps->vb_ptr->next; 00480 } 00481 if (snmp_iso_prefix_expand(msg_ps->vb_ptr->ident_len, msg_ps->vb_ptr->ident, &oid)) 00482 { 00483 //printf("snmp_msg_getnext_event ident_len %d\r\n", msg_ps->vb_ptr->ident_len ); 00484 printf("snmp_msg_getnext_event oid.len %d\r\n", oid.len ); 00485 /* 00486 int ti; 00487 for (ti = 0; (ti < oid.len) && (ti < msg_ps->vb_ptr->ident_len); ti++) 00488 { 00489 printf(".%d", oid.id[ti]); 00490 } 00491 printf("\r\n"); 00492 */ 00493 if (msg_ps->vb_ptr->ident_len > 3) 00494 { 00495 /* can offset ident_len and ident */ 00496 mn = snmp_expand_tree((struct mib_node*)&internet, 00497 msg_ps->vb_ptr->ident_len - 4, 00498 msg_ps->vb_ptr->ident + 4, &oid); 00499 } 00500 else 00501 { 00502 /* can't offset ident_len -4, ident + 4 */ 00503 mn = snmp_expand_tree((struct mib_node*)&internet, 0, NULL, &oid); 00504 } 00505 } 00506 else 00507 { 00508 mn = NULL; 00509 } 00510 if (mn != NULL) 00511 { 00512 if (mn->node_type == MIB_NODE_EX) 00513 { 00514 /* external object */ 00515 struct mib_external_node *en = (struct mib_external_node*)mn; 00516 00517 msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF; 00518 /* save en && args in msg_ps!! */ 00519 msg_ps->ext_mib_node = en; 00520 msg_ps->ext_oid = oid; 00521 00522 en->get_object_def_q(en->addr_inf, request_id, 1, &oid.id[oid.len - 1]); 00523 } 00524 else 00525 { 00526 /* internal object */ 00527 struct obj_def object_def; 00528 struct snmp_varbind *vb; 00529 00530 msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF; 00531 mn->get_object_def(1, &oid.id[oid.len - 1], &object_def); 00532 00533 LWIP_ASSERT("invalid length", object_def.v_len <= 0xff); 00534 vb = snmp_varbind_alloc(&oid, object_def.asn_type, (u8_t)object_def.v_len); 00535 if (vb != NULL) 00536 { 00537 msg_ps->state = SNMP_MSG_INTERNAL_GET_VALUE; 00538 mn->get_value(&object_def, object_def.v_len, vb->value); 00539 snmp_varbind_tail_add(&msg_ps->outvb, vb); 00540 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00541 msg_ps->vb_idx += 1; 00542 } 00543 else 00544 { 00545 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_recv couldn't allocate outvb space\n")); 00546 snmp_error_response(msg_ps,SNMP_ES_TOOBIG); 00547 } 00548 } 00549 } 00550 if (mn == NULL) 00551 { 00552 /* mn == NULL, noSuchName */ 00553 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00554 } 00555 } 00556 if ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && 00557 (msg_ps->vb_idx == msg_ps->invb.count)) 00558 { 00559 snmp_ok_response(msg_ps); 00560 } 00561 } 00562 00563 /** 00564 * Service an internal or external event for SNMP SET. 00565 * 00566 * @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) 00567 * @param msg_ps points to the assosicated message process state 00568 */ 00569 static void 00570 snmp_msg_set_event(u8_t request_id, struct snmp_msg_pstat *msg_ps) 00571 { 00572 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_msg_set_event: msg_ps->state==%"U16_F"\n",(u16_t)msg_ps->state)); 00573 00574 printf("snmp_msg_set_event: msg_ps->state==%d\r\n",(u16_t)msg_ps->state); 00575 if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF) 00576 { 00577 struct mib_external_node *en; 00578 struct snmp_name_ptr np; 00579 00580 /* get_object_def() answer*/ 00581 en = msg_ps->ext_mib_node; 00582 np = msg_ps->ext_name_ptr; 00583 00584 /* translate answer into a known lifeform */ 00585 en->get_object_def_a(request_id, np.ident_len, np.ident, &msg_ps->ext_object_def); 00586 if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) 00587 { 00588 msg_ps->state = SNMP_MSG_EXTERNAL_SET_TEST; 00589 en->set_test_q(request_id, &msg_ps->ext_object_def); 00590 } 00591 else 00592 { 00593 en->get_object_def_pc(request_id, np.ident_len, np.ident); 00594 /* search failed, object id points to unknown object (nosuchname) */ 00595 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00596 } 00597 } 00598 else if (msg_ps->state == SNMP_MSG_EXTERNAL_SET_TEST) 00599 { 00600 struct mib_external_node *en; 00601 00602 /* set_test() answer*/ 00603 en = msg_ps->ext_mib_node; 00604 00605 if (msg_ps->ext_object_def.access & MIB_ACCESS_WRITE) 00606 { 00607 printf("SNMP_MSG_EXTERNAL_SET_TEST: msg_ps->vb_ptr->value %d", msg_ps->vb_ptr->value); 00608 if ((msg_ps->ext_object_def.asn_type == msg_ps->vb_ptr->value_type) && 00609 (en->set_test_a(request_id,&msg_ps->ext_object_def, 00610 msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value) != 0)) 00611 { 00612 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00613 msg_ps->vb_idx += 1; 00614 } 00615 else 00616 { 00617 en->set_test_pc(request_id,&msg_ps->ext_object_def); 00618 /* bad value */ 00619 snmp_error_response(msg_ps,SNMP_ES_BADVALUE); 00620 } 00621 } 00622 else 00623 { 00624 en->set_test_pc(request_id,&msg_ps->ext_object_def); 00625 /* object not available for set */ 00626 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00627 } 00628 } 00629 else if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF_S) 00630 { 00631 struct mib_external_node *en; 00632 struct snmp_name_ptr np; 00633 00634 /* get_object_def() answer*/ 00635 en = msg_ps->ext_mib_node; 00636 np = msg_ps->ext_name_ptr; 00637 00638 /* translate answer into a known lifeform */ 00639 en->get_object_def_a(request_id, np.ident_len, np.ident, &msg_ps->ext_object_def); 00640 if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) 00641 { 00642 msg_ps->state = SNMP_MSG_EXTERNAL_SET_VALUE; 00643 en->set_value_q(request_id, &msg_ps->ext_object_def, 00644 msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value); 00645 } 00646 else 00647 { 00648 en->get_object_def_pc(request_id, np.ident_len, np.ident); 00649 /* set_value failed, object has disappeared for some odd reason?? */ 00650 snmp_error_response(msg_ps,SNMP_ES_GENERROR); 00651 } 00652 } 00653 else if (msg_ps->state == SNMP_MSG_EXTERNAL_SET_VALUE) 00654 { 00655 struct mib_external_node *en; 00656 00657 printf("SNMP_MSG_EXTERNAL_SET_VALUE: msg_ps->vb_ptr->value %d", msg_ps->vb_ptr->value); 00658 /** set_value_a() */ 00659 en = msg_ps->ext_mib_node; 00660 en->set_value_a(request_id, &msg_ps->ext_object_def, 00661 msg_ps->vb_ptr->value_len, msg_ps->vb_ptr->value); 00662 00663 /** @todo use set_value_pc() if toobig */ 00664 msg_ps->state = SNMP_MSG_INTERNAL_SET_VALUE; 00665 msg_ps->vb_idx += 1; 00666 } 00667 00668 /* test all values before setting */ 00669 while ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && 00670 (msg_ps->vb_idx < msg_ps->invb.count)) 00671 { 00672 struct mib_node *mn; 00673 struct snmp_name_ptr np; 00674 00675 if (msg_ps->vb_idx == 0) 00676 { 00677 msg_ps->vb_ptr = msg_ps->invb.head; 00678 } 00679 else 00680 { 00681 msg_ps->vb_ptr = msg_ps->vb_ptr->next; 00682 } 00683 /** test object identifier for .iso.org.dod.internet prefix */ 00684 if (snmp_iso_prefix_tst(msg_ps->vb_ptr->ident_len, msg_ps->vb_ptr->ident)) 00685 { 00686 mn = snmp_search_tree((struct mib_node*)&internet, msg_ps->vb_ptr->ident_len - 4, 00687 msg_ps->vb_ptr->ident + 4, &np); 00688 if (mn != NULL) 00689 { 00690 //printf("\r\nsnmp_msg_set_event: mn->node_type %d\r\n", mn->node_type); 00691 if (mn->node_type == MIB_NODE_EX) 00692 { 00693 /* external object */ 00694 struct mib_external_node *en = (struct mib_external_node*)mn; 00695 00696 msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF; 00697 /* save en && args in msg_ps!! */ 00698 msg_ps->ext_mib_node = en; 00699 msg_ps->ext_name_ptr = np; 00700 00701 en->get_object_def_q(en->addr_inf, request_id, np.ident_len, np.ident); 00702 } 00703 else 00704 { 00705 /* internal object */ 00706 struct obj_def object_def; 00707 00708 msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF; 00709 mn->get_object_def(np.ident_len, np.ident, &object_def); 00710 if (object_def.instance != MIB_OBJECT_NONE) 00711 { 00712 mn = mn; 00713 } 00714 else 00715 { 00716 /* search failed, object id points to unknown object (nosuchname) */ 00717 mn = NULL; 00718 } 00719 if (mn != NULL) 00720 { 00721 msg_ps->state = SNMP_MSG_INTERNAL_SET_TEST; 00722 //printf("\r\nsnmp_msg_set_event: msg_ps->state %d\r\n", msg_ps->state); 00723 00724 if (object_def.access & MIB_ACCESS_WRITE) 00725 { 00726 printf("\r\nsnmp_msg_set_event: object_def.asn_type %d,msg_ps->vb_ptr->value_type %d\r\n",object_def.asn_type, msg_ps->vb_ptr->value_type); 00727 //printf("snmp_msg_set_event: *msg_ps->vb_ptr->value %d,msg_ps->vb_ptr->value_len %d\r\n",*(u16_t*)msg_ps->vb_ptr->value, msg_ps->vb_ptr->value_len); 00728 if ((object_def.asn_type == msg_ps->vb_ptr->value_type) && 00729 (mn->set_test(&object_def,msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value) != 0)) 00730 { 00731 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00732 msg_ps->vb_idx += 1; 00733 } 00734 else 00735 { 00736 /* bad value */ 00737 snmp_error_response(msg_ps,SNMP_ES_BADVALUE); 00738 } 00739 } 00740 else 00741 { 00742 /* object not available for set */ 00743 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00744 } 00745 } 00746 } 00747 } 00748 } 00749 else 00750 { 00751 mn = NULL; 00752 } 00753 if (mn == NULL) 00754 { 00755 /* mn == NULL, noSuchName */ 00756 snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); 00757 } 00758 } 00759 00760 if ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && 00761 (msg_ps->vb_idx == msg_ps->invb.count)) 00762 { 00763 msg_ps->vb_idx = 0; 00764 msg_ps->state = SNMP_MSG_INTERNAL_SET_VALUE; 00765 } 00766 00767 /* set all values "atomically" (be as "atomic" as possible) */ 00768 while ((msg_ps->state == SNMP_MSG_INTERNAL_SET_VALUE) && 00769 (msg_ps->vb_idx < msg_ps->invb.count)) 00770 { 00771 struct mib_node *mn; 00772 struct snmp_name_ptr np; 00773 00774 if (msg_ps->vb_idx == 0) 00775 { 00776 msg_ps->vb_ptr = msg_ps->invb.head; 00777 } 00778 else 00779 { 00780 msg_ps->vb_ptr = msg_ps->vb_ptr->next; 00781 } 00782 /* skip iso prefix test, was done previously while settesting() */ 00783 mn = snmp_search_tree((struct mib_node*)&internet, msg_ps->vb_ptr->ident_len - 4, 00784 msg_ps->vb_ptr->ident + 4, &np); 00785 /* check if object is still available 00786 (e.g. external hot-plug thingy present?) */ 00787 if (mn != NULL) 00788 { 00789 if (mn->node_type == MIB_NODE_EX) 00790 { 00791 /* external object */ 00792 struct mib_external_node *en = (struct mib_external_node*)mn; 00793 00794 msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF_S; 00795 /* save en && args in msg_ps!! */ 00796 msg_ps->ext_mib_node = en; 00797 msg_ps->ext_name_ptr = np; 00798 00799 en->get_object_def_q(en->addr_inf, request_id, np.ident_len, np.ident); 00800 } 00801 else 00802 { 00803 /* internal object */ 00804 struct obj_def object_def; 00805 00806 msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF_S; 00807 mn->get_object_def(np.ident_len, np.ident, &object_def); 00808 msg_ps->state = SNMP_MSG_INTERNAL_SET_VALUE; 00809 mn->set_value(&object_def,msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value); 00810 msg_ps->vb_idx += 1; 00811 } 00812 } 00813 } 00814 if ((msg_ps->state == SNMP_MSG_INTERNAL_SET_VALUE) && 00815 (msg_ps->vb_idx == msg_ps->invb.count)) 00816 { 00817 /* simply echo the input if we can set it 00818 @todo do we need to return the actual value? 00819 e.g. if value is silently modified or behaves sticky? */ 00820 msg_ps->outvb = msg_ps->invb; 00821 msg_ps->invb.head = NULL; 00822 msg_ps->invb.tail = NULL; 00823 msg_ps->invb.count = 0; 00824 snmp_ok_response(msg_ps); 00825 } 00826 } 00827 00828 00829 /** 00830 * Handle one internal or external event. 00831 * Called for one async event. (recv external/private answer) 00832 * 00833 * @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) 00834 */ 00835 void 00836 snmp_msg_event(u8_t request_id) 00837 { 00838 struct snmp_msg_pstat *msg_ps; 00839 00840 if (request_id < SNMP_CONCURRENT_REQUESTS) 00841 { 00842 msg_ps = &msg_input_list[request_id]; 00843 printf("\r\nsnmp_msg_event: msg_ps->rt %d\r\n", msg_ps->rt); 00844 if (msg_ps->rt == SNMP_ASN1_PDU_GET_NEXT_REQ) 00845 { 00846 snmp_msg_getnext_event(request_id, msg_ps); 00847 } 00848 else if (msg_ps->rt == SNMP_ASN1_PDU_GET_REQ) 00849 { 00850 snmp_msg_get_event(request_id, msg_ps); 00851 } 00852 else if(msg_ps->rt == SNMP_ASN1_PDU_SET_REQ) 00853 { 00854 snmp_msg_set_event(request_id, msg_ps); 00855 } 00856 } 00857 } 00858 00859 00860 /* lwIP UDP receive callback function */ 00861 static void 00862 snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, ip_addr_t *addr, u16_t port) 00863 { 00864 struct snmp_msg_pstat *msg_ps; 00865 u8_t req_idx; 00866 err_t err_ret; 00867 u16_t payload_len = p->tot_len; 00868 u16_t payload_ofs = 0; 00869 u16_t varbind_ofs = 0; 00870 blink_led = true; // v0.1 00871 00872 /* suppress unused argument warning */ 00873 LWIP_UNUSED_ARG(arg); 00874 00875 /* traverse input message process list, look for SNMP_MSG_EMPTY */ 00876 msg_ps = &msg_input_list[0]; 00877 req_idx = 0; 00878 while ((req_idx < SNMP_CONCURRENT_REQUESTS) && (msg_ps->state != SNMP_MSG_EMPTY)) 00879 { 00880 req_idx++; 00881 msg_ps++; 00882 } 00883 printf("\r\nsnmp_recv: datagram length %"U16_F" and req_idx = %d\r\n", p->tot_len, req_idx); 00884 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_recv port %d\r\n", port)); 00885 if (req_idx == SNMP_CONCURRENT_REQUESTS) 00886 { 00887 /* exceeding number of concurrent requests */ 00888 printf("\r\nsnmp_recv: exceeded SNMP_CONCURRENT_REQUESTS\r\n"); 00889 pbuf_free(p); 00890 return; 00891 } 00892 00893 /* accepting request */ 00894 snmp_inc_snmpinpkts(); 00895 /* record used 'protocol control block' */ 00896 msg_ps->pcb = pcb; 00897 /* source address (network order) */ 00898 msg_ps->sip = *addr; 00899 /* source port (host order (lwIP oddity)) */ 00900 msg_ps->sp = port; 00901 00902 /* check total length, version, community, pdu type */ 00903 err_ret = snmp_pdu_header_check(p, payload_ofs, payload_len, &varbind_ofs, msg_ps); 00904 /* Only accept requests and requests without error (be robust) */ 00905 /* Reject response and trap headers or error requests as input! */ 00906 if ((err_ret != ERR_OK) || 00907 ((msg_ps->rt != SNMP_ASN1_PDU_GET_REQ) && 00908 (msg_ps->rt != SNMP_ASN1_PDU_GET_NEXT_REQ) && 00909 (msg_ps->rt != SNMP_ASN1_PDU_SET_REQ)) || 00910 ((msg_ps->error_status != SNMP_ES_NOERROR) || 00911 (msg_ps->error_index != 0)) ) 00912 { 00913 /* header check failed drop request silently, do not return error! */ 00914 pbuf_free(p); 00915 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_pdu_header_check() failed\n")); 00916 return; 00917 } 00918 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_recv ok, community %s and req type %d\r\n", msg_ps->community, msg_ps->rt)); 00919 00920 /* Builds a list of variable bindings. Copy the varbinds from the pbuf 00921 chain to glue them when these are divided over two or more pbuf's. */ 00922 err_ret = snmp_pdu_dec_varbindlist(p, varbind_ofs, &varbind_ofs, msg_ps); 00923 /* we've decoded the incoming message, release input msg now */ 00924 pbuf_free(p); 00925 if ((err_ret != ERR_OK) || (msg_ps->invb.count == 0)) 00926 { 00927 /* varbind-list decode failed, or varbind list empty. 00928 drop request silently, do not return error! 00929 (errors are only returned for a specific varbind failure) */ 00930 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_pdu_dec_varbindlist() failed\n")); 00931 return; 00932 } 00933 00934 msg_ps->error_status = SNMP_ES_NOERROR; 00935 msg_ps->error_index = 0; 00936 /* find object for each variable binding */ 00937 msg_ps->state = SNMP_MSG_SEARCH_OBJ; 00938 /* first variable binding from list to inspect */ 00939 msg_ps->vb_idx = 0; 00940 00941 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_recv varbind cnt=%"U16_F"\n",(u16_t)msg_ps->invb.count)); 00942 00943 /* handle input event and as much objects as possible in one go */ 00944 snmp_msg_event(req_idx); 00945 } 00946 00947 /** 00948 * Checks and decodes incoming SNMP message header, logs header errors. 00949 * 00950 * @param p points to pbuf chain of SNMP message (UDP payload) 00951 * @param ofs points to first octet of SNMP message 00952 * @param pdu_len the length of the UDP payload 00953 * @param ofs_ret returns the ofset of the variable bindings 00954 * @param m_stat points to the current message request state return 00955 * @return 00956 * - ERR_OK SNMP header is sane and accepted 00957 * - ERR_ARG SNMP header is either malformed or rejected 00958 */ 00959 static err_t 00960 snmp_pdu_header_check(struct pbuf *p, u16_t ofs, u16_t pdu_len, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat) 00961 { 00962 err_t derr; 00963 u16_t len, ofs_base; 00964 u8_t len_octets; 00965 u8_t type; 00966 s32_t version; 00967 00968 /* diagnostics 00969 u8_t *msg_ptr; 00970 00971 msg_ptr = (u8_t*)p->payload; 00972 printf("\r\nOffset %d, Header : ", ofs); 00973 for(len = 0; len < 24; len++) 00974 { 00975 printf("%d, ", msg_ptr[len]); 00976 } 00977 printf("\r\n"); 00978 for(len = 24; len < 48; len++) 00979 { 00980 printf("%d, ", msg_ptr[len]); 00981 } 00982 printf("\r\n"); 00983 for(len = 48; len < 72; len++) 00984 { 00985 printf("%d, ", msg_ptr[len]); 00986 } 00987 printf("\r\n"); 00988 for(len = 72; len < 96; len++) 00989 { 00990 printf("%d, ", msg_ptr[len]); 00991 } 00992 printf("\r\n"); 00993 for(len = 96; len < 112; len++) 00994 { 00995 printf("%d, ", msg_ptr[len]); 00996 } 00997 printf("\r\n"); 00998 */ 00999 ofs_base = ofs; 01000 snmp_asn1_dec_type(p, ofs, &type); 01001 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01002 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01003 if ((derr != ERR_OK) || 01004 (pdu_len != (1 + len_octets + len)) || 01005 (type != (SNMP_ASN1_UNIV | SNMP_ASN1_CONSTR | SNMP_ASN1_SEQ))) 01006 { 01007 snmp_inc_snmpinasnparseerrs(); 01008 return ERR_ARG; 01009 } 01010 ofs += (1 + len_octets); 01011 snmp_asn1_dec_type(p, ofs, &type); 01012 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01013 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01014 if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) 01015 { 01016 /* can't decode or no integer (version) */ 01017 snmp_inc_snmpinasnparseerrs(); 01018 return ERR_ARG; 01019 } 01020 derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &version); 01021 //printf("\r\nofs %d, version %d, len %d, len_octets %d \r\n", ofs, version, len, len_octets); 01022 if (derr != ERR_OK) 01023 { 01024 /* can't decode */ 01025 snmp_inc_snmpinasnparseerrs(); 01026 return ERR_ARG; 01027 } 01028 if (version != 0) 01029 { 01030 /* not version 1 */ 01031 snmp_inc_snmpinbadversions(); 01032 return ERR_ARG; 01033 } 01034 ofs += (1 + len_octets + len); 01035 snmp_asn1_dec_type(p, ofs, &type); 01036 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01037 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01038 if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OC_STR))) 01039 { 01040 /* can't decode or no octet string (community) */ 01041 snmp_inc_snmpinasnparseerrs(); 01042 return ERR_ARG; 01043 } 01044 derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, SNMP_COMMUNITY_STR_LEN, m_stat->community); 01045 if (derr != ERR_OK) 01046 { 01047 snmp_inc_snmpinasnparseerrs(); 01048 return ERR_ARG; 01049 } 01050 /* add zero terminator */ 01051 len = ((len < (SNMP_COMMUNITY_STR_LEN))?(len):(SNMP_COMMUNITY_STR_LEN)); 01052 m_stat->community[len] = 0; 01053 m_stat->com_strlen = (u8_t)len; 01054 //printf("\r\n community %s, len %d\r\n", m_stat->community, len); 01055 if (strncmp(snmp_publiccommunity, (const char*)m_stat->community, SNMP_COMMUNITY_STR_LEN) != 0) 01056 { 01057 /** @todo: move this if we need to check more names */ 01058 snmp_inc_snmpinbadcommunitynames(); 01059 snmp_authfail_trap(); 01060 return ERR_ARG; 01061 } 01062 //printf("\r\nofs %d, community %s, len %d, len_octets %d \r\n", ofs, m_stat->community, len, len_octets); 01063 ofs += (1 + len_octets + len); 01064 snmp_asn1_dec_type(p, ofs, &type); 01065 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01066 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01067 if (derr != ERR_OK) 01068 { 01069 snmp_inc_snmpinasnparseerrs(); 01070 return ERR_ARG; 01071 } 01072 switch(type) 01073 { 01074 case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_GET_REQ): 01075 /* GetRequest PDU */ 01076 snmp_inc_snmpingetrequests(); 01077 printf("\r\nGET_REQ\r\n"); 01078 derr = ERR_OK; 01079 break; 01080 case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_GET_NEXT_REQ): 01081 /* GetNextRequest PDU */ 01082 snmp_inc_snmpingetnexts(); 01083 printf("\r\nGET_NXT\r\n"); 01084 derr = ERR_OK; 01085 break; 01086 case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_GET_RESP): 01087 /* GetResponse PDU */ 01088 snmp_inc_snmpingetresponses(); 01089 derr = ERR_ARG; 01090 break; 01091 case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_SET_REQ): 01092 /* SetRequest PDU */ 01093 printf("\r\nSET_REQ\r\n"); 01094 snmp_inc_snmpinsetrequests(); 01095 derr = ERR_OK; 01096 break; 01097 case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_TRAP): 01098 /* Trap PDU */ 01099 snmp_inc_snmpintraps(); 01100 derr = ERR_ARG; 01101 break; 01102 default: 01103 snmp_inc_snmpinasnparseerrs(); 01104 derr = ERR_ARG; 01105 break; 01106 } 01107 if (derr != ERR_OK) 01108 { 01109 /* unsupported input PDU for this agent (no parse error) */ 01110 return ERR_ARG; 01111 } 01112 m_stat->rt = type & 0x1F; 01113 ofs += (1 + len_octets); 01114 if (len != (pdu_len - (ofs - ofs_base))) 01115 { 01116 /* decoded PDU length does not equal actual payload length */ 01117 snmp_inc_snmpinasnparseerrs(); 01118 return ERR_ARG; 01119 } 01120 snmp_asn1_dec_type(p, ofs, &type); 01121 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01122 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01123 if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) 01124 { 01125 /* can't decode or no integer (request ID) */ 01126 snmp_inc_snmpinasnparseerrs(); 01127 return ERR_ARG; 01128 } 01129 derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &m_stat->rid); 01130 //printf("\r\nofs %d, m_stat->rid %d, len %d, len_octets %d \r\n", ofs, m_stat->rid, len, len_octets); 01131 if (derr != ERR_OK) 01132 { 01133 /* can't decode */ 01134 snmp_inc_snmpinasnparseerrs(); 01135 return ERR_ARG; 01136 } 01137 ofs += (1 + len_octets + len); 01138 snmp_asn1_dec_type(p, ofs, &type); 01139 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01140 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01141 if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) 01142 { 01143 /* can't decode or no integer (error-status) */ 01144 snmp_inc_snmpinasnparseerrs(); 01145 return ERR_ARG; 01146 } 01147 /* must be noError (0) for incoming requests. 01148 log errors for mib-2 completeness and for debug purposes */ 01149 derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &m_stat->error_status); 01150 if (derr != ERR_OK) 01151 { 01152 /* can't decode */ 01153 snmp_inc_snmpinasnparseerrs(); 01154 return ERR_ARG; 01155 } 01156 switch (m_stat->error_status) 01157 { 01158 case SNMP_ES_TOOBIG: 01159 snmp_inc_snmpintoobigs(); 01160 break; 01161 case SNMP_ES_NOSUCHNAME: 01162 snmp_inc_snmpinnosuchnames(); 01163 break; 01164 case SNMP_ES_BADVALUE: 01165 snmp_inc_snmpinbadvalues(); 01166 break; 01167 case SNMP_ES_READONLY: 01168 snmp_inc_snmpinreadonlys(); 01169 break; 01170 case SNMP_ES_GENERROR: 01171 snmp_inc_snmpingenerrs(); 01172 break; 01173 } 01174 ofs += (1 + len_octets + len); 01175 snmp_asn1_dec_type(p, ofs, &type); 01176 //printf("\r\nofs %d, type %d, len %d, len_octets %d \r\n", ofs, type, len, len_octets); 01177 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01178 if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) 01179 { 01180 /* can't decode or no integer (error-index) */ 01181 snmp_inc_snmpinasnparseerrs(); 01182 return ERR_ARG; 01183 } 01184 /* must be 0 for incoming requests. 01185 decode anyway to catch bad integers (and dirty tricks) */ 01186 derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &m_stat->error_index); 01187 if (derr != ERR_OK) 01188 { 01189 /* can't decode */ 01190 snmp_inc_snmpinasnparseerrs(); 01191 return ERR_ARG; 01192 } 01193 ofs += (1 + len_octets + len); 01194 printf("\r\noffset %d exit \r\n", ofs); 01195 *ofs_ret = ofs; 01196 return ERR_OK; 01197 } 01198 01199 static err_t 01200 snmp_pdu_dec_varbindlist(struct pbuf *p, u16_t ofs, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat) 01201 { 01202 err_t derr; 01203 u16_t len, vb_len; 01204 u8_t len_octets; 01205 u8_t type; 01206 01207 /* variable binding list */ 01208 snmp_asn1_dec_type(p, ofs, &type); 01209 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &vb_len); 01210 // LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 1 err: %d , offset %d, type %d and length %d\r\n", derr, ofs, type, vb_len)); 01211 if ((derr != ERR_OK) || 01212 (type != (SNMP_ASN1_UNIV | SNMP_ASN1_CONSTR | SNMP_ASN1_SEQ))) 01213 { 01214 snmp_inc_snmpinasnparseerrs(); 01215 return ERR_ARG; 01216 } 01217 ofs += (1 + len_octets); 01218 01219 /* start with empty list */ 01220 m_stat->invb.count = 0; 01221 m_stat->invb.head = NULL; 01222 m_stat->invb.tail = NULL; 01223 01224 while (vb_len > 0) 01225 { 01226 struct snmp_obj_id oid, oid_value; 01227 struct snmp_varbind *vb; 01228 01229 snmp_asn1_dec_type(p, ofs, &type); 01230 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01231 //LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 2 err: %d, offset %d and length %d\r\n", derr, ofs, len)); 01232 if ((derr != ERR_OK) || 01233 (type != (SNMP_ASN1_UNIV | SNMP_ASN1_CONSTR | SNMP_ASN1_SEQ)) || 01234 (len == 0) || (len > vb_len)) 01235 { 01236 snmp_inc_snmpinasnparseerrs(); 01237 /* free varbinds (if available) */ 01238 snmp_varbind_list_free(&m_stat->invb); 01239 return ERR_ARG; 01240 } 01241 ofs += (1 + len_octets); 01242 vb_len -= (1 + len_octets); 01243 01244 snmp_asn1_dec_type(p, ofs, &type); 01245 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01246 //LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 3 err: %d, offset %d and type %d\r\n", derr, ofs, type)); 01247 if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OBJ_ID))) 01248 { 01249 /* can't decode object name length */ 01250 snmp_inc_snmpinasnparseerrs(); 01251 /* free varbinds (if available) */ 01252 snmp_varbind_list_free(&m_stat->invb); 01253 return ERR_ARG; 01254 } 01255 derr = snmp_asn1_dec_oid(p, ofs + 1 + len_octets, len, &oid); 01256 //LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 4 err: %d, offset %d\r\n", derr, ofs)); 01257 if (derr != ERR_OK) 01258 { 01259 /* can't decode object name */ 01260 snmp_inc_snmpinasnparseerrs(); 01261 /* free varbinds (if available) */ 01262 snmp_varbind_list_free(&m_stat->invb); 01263 return ERR_ARG; 01264 } 01265 ofs += (1 + len_octets + len); 01266 vb_len -= (1 + len_octets + len); 01267 01268 snmp_asn1_dec_type(p, ofs, &type); 01269 derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); 01270 //LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 5 err: %d, offset %d, type %d, and length %d\r\n", derr, ofs, type, len)); 01271 if (derr != ERR_OK) 01272 { 01273 /* can't decode object value length */ 01274 snmp_inc_snmpinasnparseerrs(); 01275 /* free varbinds (if available) */ 01276 snmp_varbind_list_free(&m_stat->invb); 01277 return ERR_ARG; 01278 } 01279 01280 //LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 5 type: %d\r\n", type)); 01281 switch (type) 01282 { 01283 case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG): 01284 vb = snmp_varbind_alloc(&oid, type, sizeof(s32_t)); 01285 if (vb != NULL) 01286 { 01287 s32_t *vptr = (s32_t*)vb->value; 01288 01289 derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, vptr); 01290 snmp_varbind_tail_add(&m_stat->invb, vb); 01291 } 01292 else 01293 { 01294 derr = ERR_ARG; 01295 } 01296 break; 01297 case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_COUNTER): 01298 case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_GAUGE): 01299 case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_TIMETICKS): 01300 vb = snmp_varbind_alloc(&oid, type, sizeof(u32_t)); 01301 if (vb != NULL) 01302 { 01303 u32_t *vptr = (u32_t*)vb->value; 01304 01305 derr = snmp_asn1_dec_u32t(p, ofs + 1 + len_octets, len, vptr); 01306 snmp_varbind_tail_add(&m_stat->invb, vb); 01307 } 01308 else 01309 { 01310 derr = ERR_ARG; 01311 } 01312 break; 01313 case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OC_STR): 01314 case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_OPAQUE): 01315 LWIP_ASSERT("invalid length", len <= 0xff); 01316 vb = snmp_varbind_alloc(&oid, type, (u8_t)len); 01317 if (vb != NULL) 01318 { 01319 derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, vb->value_len, (u8_t*)vb->value); 01320 snmp_varbind_tail_add(&m_stat->invb, vb); 01321 } 01322 else 01323 { 01324 derr = ERR_ARG; 01325 } 01326 break; 01327 case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_NUL): 01328 vb = snmp_varbind_alloc(&oid, type, 0); 01329 if (vb != NULL) 01330 { 01331 snmp_varbind_tail_add(&m_stat->invb, vb); 01332 derr = ERR_OK; 01333 } 01334 else 01335 { 01336 derr = ERR_ARG; 01337 } 01338 break; 01339 case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OBJ_ID): 01340 derr = snmp_asn1_dec_oid(p, ofs + 1 + len_octets, len, &oid_value); 01341 if (derr == ERR_OK) 01342 { 01343 vb = snmp_varbind_alloc(&oid, type, oid_value.len * sizeof(s32_t)); 01344 if (vb != NULL) 01345 { 01346 u8_t i = oid_value.len; 01347 s32_t *vptr = (s32_t*)vb->value; 01348 01349 while(i > 0) 01350 { 01351 i--; 01352 vptr[i] = oid_value.id[i]; 01353 } 01354 snmp_varbind_tail_add(&m_stat->invb, vb); 01355 derr = ERR_OK; 01356 } 01357 else 01358 { 01359 derr = ERR_ARG; 01360 } 01361 } 01362 break; 01363 case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_IPADDR): 01364 if (len == 4) 01365 { 01366 /* must be exactly 4 octets! */ 01367 vb = snmp_varbind_alloc(&oid, type, 4); 01368 if (vb != NULL) 01369 { 01370 derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, vb->value_len, (u8_t*)vb->value); 01371 snmp_varbind_tail_add(&m_stat->invb, vb); 01372 } 01373 else 01374 { 01375 derr = ERR_ARG; 01376 } 01377 } 01378 else 01379 { 01380 derr = ERR_ARG; 01381 } 01382 break; 01383 default: 01384 derr = ERR_ARG; 01385 break; 01386 } 01387 // LWIP_DEBUGF(SNMP_MSG_DEBUG, ("varbindlist 6 err: %d\r\n", derr)); 01388 if (derr != ERR_OK) 01389 { 01390 snmp_inc_snmpinasnparseerrs(); 01391 /* free varbinds (if available) */ 01392 snmp_varbind_list_free(&m_stat->invb); 01393 return ERR_ARG; 01394 } 01395 ofs += (1 + len_octets + len); 01396 vb_len -= (1 + len_octets + len); 01397 } 01398 01399 if (m_stat->rt == SNMP_ASN1_PDU_SET_REQ) 01400 { 01401 snmp_add_snmpintotalsetvars(m_stat->invb.count); 01402 } 01403 else 01404 { 01405 snmp_add_snmpintotalreqvars(m_stat->invb.count); 01406 } 01407 01408 *ofs_ret = ofs; 01409 return ERR_OK; 01410 } 01411 01412 struct snmp_varbind* 01413 snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u8_t len) 01414 { 01415 struct snmp_varbind *vb; 01416 01417 vb = (struct snmp_varbind *)memp_malloc(MEMP_SNMP_VARBIND); 01418 LWIP_ASSERT("vb != NULL",vb != NULL); 01419 if (vb != NULL) 01420 { 01421 u8_t i; 01422 01423 vb->next = NULL; 01424 vb->prev = NULL; 01425 i = oid->len; 01426 vb->ident_len = i; 01427 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_varbind_alloc: oid length: %d\r\n", i)); 01428 if (i > 0) 01429 { 01430 LWIP_ASSERT("SNMP_MAX_TREE_DEPTH is configured too low", i <= SNMP_MAX_TREE_DEPTH); 01431 /* allocate array of s32_t for our object identifier */ 01432 vb->ident = (s32_t*)memp_malloc(MEMP_SNMP_VALUE); 01433 LWIP_ASSERT("vb->ident != NULL",vb->ident != NULL); 01434 if (vb->ident == NULL) 01435 { 01436 memp_free(MEMP_SNMP_VARBIND, vb); 01437 return NULL; 01438 } 01439 while(i > 0) 01440 { 01441 i--; 01442 vb->ident[i] = oid->id[i]; 01443 printf(".%d", vb->ident[i]); 01444 } 01445 printf(" Reversed oid\r\n"); 01446 } 01447 else 01448 { 01449 /* i == 0, pass zero length object identifier */ 01450 vb->ident = NULL; 01451 } 01452 vb->value_type = type; 01453 vb->value_len = len; 01454 LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_varbind_alloc: value type %d and len: %d\r\n", type, len)); 01455 if (len > 0) 01456 { 01457 LWIP_ASSERT("SNMP_MAX_OCTET_STRING_LEN is configured too low", vb->value_len <= SNMP_MAX_VALUE_SIZE); 01458 /* allocate raw bytes for our object value */ 01459 vb->value = memp_malloc(MEMP_SNMP_VALUE); 01460 LWIP_ASSERT("vb->value != NULL",vb->value != NULL); 01461 if (vb->value == NULL) 01462 { 01463 if (vb->ident != NULL) 01464 { 01465 memp_free(MEMP_SNMP_VALUE, vb->ident); 01466 } 01467 memp_free(MEMP_SNMP_VARBIND, vb); 01468 return NULL; 01469 } 01470 } 01471 else 01472 { 01473 /* ASN1_NUL type, or zero length ASN1_OC_STR */ 01474 vb->value = NULL; 01475 } 01476 } 01477 return vb; 01478 } // end snmp_varbind_alloc 01479 01480 void 01481 snmp_varbind_free(struct snmp_varbind *vb) 01482 { 01483 if (vb->value != NULL ) 01484 { 01485 memp_free(MEMP_SNMP_VALUE, vb->value); 01486 } 01487 if (vb->ident != NULL ) 01488 { 01489 memp_free(MEMP_SNMP_VALUE, vb->ident); 01490 } 01491 memp_free(MEMP_SNMP_VARBIND, vb); 01492 } 01493 01494 void 01495 snmp_varbind_list_free(struct snmp_varbind_root *root) 01496 { 01497 struct snmp_varbind *vb, *prev; 01498 01499 vb = root->tail; 01500 while ( vb != NULL ) 01501 { 01502 prev = vb->prev; 01503 snmp_varbind_free(vb); 01504 vb = prev; 01505 } 01506 root->count = 0; 01507 root->head = NULL; 01508 root->tail = NULL; 01509 } 01510 01511 void 01512 snmp_varbind_tail_add(struct snmp_varbind_root *root, struct snmp_varbind *vb) 01513 { 01514 if (root->count == 0) 01515 { 01516 /* add first varbind to list */ 01517 root->head = vb; 01518 root->tail = vb; 01519 } 01520 else 01521 { 01522 /* add nth varbind to list tail */ 01523 root->tail->next = vb; 01524 vb->prev = root->tail; 01525 root->tail = vb; 01526 } 01527 root->count += 1; 01528 } 01529 01530 struct snmp_varbind* 01531 snmp_varbind_tail_remove(struct snmp_varbind_root *root) 01532 { 01533 struct snmp_varbind* vb; 01534 01535 if (root->count > 0) 01536 { 01537 /* remove tail varbind */ 01538 vb = root->tail; 01539 root->tail = vb->prev; 01540 vb->prev->next = NULL; 01541 root->count -= 1; 01542 } 01543 else 01544 { 01545 /* nothing to remove */ 01546 vb = NULL; 01547 } 01548 return vb; 01549 } 01550 01551 #endif /* LWIP_SNMP */
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