fixed bug #43790: Sending octet string of Length >255 from SNMP agent (patch by Manoj Kumar)

CHANGELOG

@@ -249,6 +249,10 @@ HISTORY
 
   ++ Bugfixes:
 
+  2015-08-20: Manoj Kumar
+  * snmp_msg.h, msg_in.c: fixed bug #43790: Sending octet string of Length >255
+    from SNMP agent
+
   2015-08-19: Jens Nielsen
   * icmp.c, ip4.c, tcp_in.c, udp.c, raw.c: fixed bug #45120: Broadcast & multiple
     interfaces handling

src/core/snmp/msg_in.c

@@ -293,8 +293,7 @@ snmp_msg_get_event(u8_t request_id, struct snmp_msg_pstat *msg_ps)
       msg_ps->vb_ptr->ident_len = 0;
 
       vb->value_type = msg_ps->ext_object_def.asn_type;
-      LWIP_ASSERT("invalid length", msg_ps->ext_object_def.v_len <= 0xff);
-      vb->value_len = (u8_t)msg_ps->ext_object_def.v_len;
+      vb->value_len = msg_ps->ext_object_def.v_len;
       if (vb->value_len > 0)
       {
         LWIP_ASSERT("SNMP_MAX_OCTET_STRING_LEN is configured too low", vb->value_len <= SNMP_MAX_VALUE_SIZE);
@@ -405,8 +404,7 @@ snmp_msg_get_event(u8_t request_id, struct snmp_msg_pstat *msg_ps)
               msg_ps->vb_ptr->ident_len = 0;
 
               vb->value_type = object_def.asn_type;
-              LWIP_ASSERT("invalid length", object_def.v_len <= 0xff);
-              vb->value_len = (u8_t)object_def.v_len;
+              vb->value_len = object_def.v_len;
               if (vb->value_len > 0)
               {
                 LWIP_ASSERT("SNMP_MAX_OCTET_STRING_LEN is configured too low",
@@ -505,10 +503,9 @@ snmp_msg_getnext_event(u8_t request_id, struct snmp_msg_pstat *msg_ps)
     /* get_value() answer */
     en = msg_ps->ext_mib_node;
 
-    LWIP_ASSERT("invalid length", msg_ps->ext_object_def.v_len <= 0xff);
     vb = snmp_varbind_alloc(&msg_ps->ext_oid,
                             msg_ps->ext_object_def.asn_type,
-                            (u8_t)msg_ps->ext_object_def.v_len);
+                            msg_ps->ext_object_def.v_len);
     if (vb != NULL)
     {
       en->get_value_a(request_id, &msg_ps->ext_object_def, vb->value_len, vb->value);
@@ -580,8 +577,7 @@ snmp_msg_getnext_event(u8_t request_id, struct snmp_msg_pstat *msg_ps)
         msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF;
         mn->get_object_def(1, &oid.id[oid.len - 1], &object_def);
 
-        LWIP_ASSERT("invalid length", object_def.v_len <= 0xff);
-        vb = snmp_varbind_alloc(&oid, object_def.asn_type, (u8_t)object_def.v_len);
+        vb = snmp_varbind_alloc(&oid, object_def.asn_type, object_def.v_len);
         if (vb != NULL)
         {
           msg_ps->state = SNMP_MSG_INTERNAL_GET_VALUE;
@@ -1318,8 +1314,7 @@ snmp_pdu_dec_varbindlist(struct pbuf *p, u16_t ofs, u16_t *ofs_ret, struct snmp_
         break;
       case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OC_STR):
       case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_OPAQUE):
-        LWIP_ASSERT("invalid length", len <= 0xff);
-        vb = snmp_varbind_alloc(&oid, type, (u8_t)len);
+        vb = snmp_varbind_alloc(&oid, type, len);
         if (vb != NULL)
         {
           derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, vb->value_len, (u8_t*)vb->value);
@@ -1415,7 +1410,7 @@ snmp_pdu_dec_varbindlist(struct pbuf *p, u16_t ofs, u16_t *ofs_ret, struct snmp_
 }
 
 struct snmp_varbind*
-snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u8_t len)
+snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u16_t len)
 {
   struct snmp_varbind *vb;
 

src/include/lwip/snmp_msg.h

@@ -91,7 +91,7 @@ struct snmp_varbind
   /* object value ASN1 type */
   u8_t value_type;
   /* object value length (in u8_t) */
-  u8_t value_len;
+  u16_t value_len;
   /* object value */
   void *value;
 
@@ -301,7 +301,7 @@ void snmp_trap_dst_enable(u8_t dst_idx, u8_t enable);
 void snmp_trap_dst_ip_set(u8_t dst_idx, ip_addr_t *dst);
 
 /** Varbind-list functions. */
-struct snmp_varbind* snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u8_t len);
+struct snmp_varbind* snmp_varbind_alloc(struct snmp_obj_id *oid, u8_t type, u16_t len);
 void snmp_varbind_free(struct snmp_varbind *vb);
 void snmp_varbind_list_free(struct snmp_varbind_root *root);
 void snmp_varbind_tail_add(struct snmp_varbind_root *root, struct snmp_varbind *vb);