Added some lines for SET command.

src/core/snmp/mib2.c

@@ -72,6 +72,8 @@
 
 static void system_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
 static void system_get_value(struct obj_def *od, u16_t len, void *value);
+static u8_t system_set_test(struct obj_def *od, u16_t len, void *value);
+static void system_set_value(struct obj_def *od, u16_t len, void *value);
 static void interfaces_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
 static void interfaces_get_value(struct obj_def *od, u16_t len, void *value);
 static void ifentry_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
@@ -80,6 +82,7 @@ static void atentry_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def
 static void atentry_get_value(struct obj_def *od, u16_t len, void *value);
 static void ip_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
 static void ip_get_value(struct obj_def *od, u16_t len, void *value);
+static u8_t ip_set_test(struct obj_def *od, u16_t len, void *value);
 static void ip_addrentry_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
 static void ip_addrentry_get_value(struct obj_def *od, u16_t len, void *value);
 static void ip_rteentry_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
@@ -100,12 +103,16 @@ static void udpentry_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def
 static void udpentry_get_value(struct obj_def *od, u16_t len, void *value);
 static void snmp_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
 static void snmp_get_value(struct obj_def *od, u16_t len, void *value);
+static u8_t snmp_set_test(struct obj_def *od, u16_t len, void *value);
+static void snmp_set_value(struct obj_def *od, u16_t len, void *value);
 
 
 /* snmp .1.3.6.1.2.1.11 */
 const mib_scalar_node snmp_scalar = {
   &snmp_get_object_def,
   &snmp_get_value,
+  &snmp_set_test,
+  &snmp_set_value,
   MIB_NODE_SC,
   0
 };
@@ -132,6 +139,8 @@ struct mib_node* const snmp_nodes[28] = {
 const struct mib_array_node snmp = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   28,
   snmp_ids,
@@ -147,6 +156,8 @@ const struct mib_array_node snmp = {
 struct mib_list_rootnode udp_root = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -160,6 +171,8 @@ struct mib_node* const udpentry_nodes[2] = {
 const struct mib_array_node udpentry = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   2,
   udpentry_ids,
@@ -171,6 +184,8 @@ struct mib_node* udptable_node = (struct mib_node* const)&udpentry;
 struct mib_ram_array_node udptable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
   0,
   &udptable_id,
@@ -180,6 +195,8 @@ struct mib_ram_array_node udptable = {
 const mib_scalar_node udp_scalar = {
   &udp_get_object_def,
   &udp_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_SC,
   0
 };
@@ -192,6 +209,8 @@ struct mib_node* const udp_nodes[5] = {
 const struct mib_array_node udp = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   5,
   udp_ids,
@@ -205,6 +224,8 @@ const struct mib_array_node udp = {
 struct mib_list_rootnode tcpconntree_root = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -220,6 +241,8 @@ struct mib_node* const tcpconnentry_nodes[5] = {
 const struct mib_array_node tcpconnentry = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   5,
   tcpconnentry_ids,
@@ -231,6 +254,8 @@ struct mib_node* tcpconntable_node = (struct mib_node* const)&tcpconnentry;
 struct mib_ram_array_node tcpconntable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
 /** @todo update maxlength when inserting / deleting from table
    0 when table is empty, 1 when more than one entry */
@@ -259,6 +284,8 @@ struct mib_node* const tcp_nodes[15] = {
 const struct mib_array_node tcp = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   15,
   tcp_ids,
@@ -270,6 +297,8 @@ const struct mib_array_node tcp = {
 const mib_scalar_node icmp_scalar = {
   &icmp_get_object_def,
   &icmp_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_SC,
   0
 };
@@ -292,6 +321,8 @@ struct mib_node* const icmp_nodes[26] = {
 const struct mib_array_node icmp = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   26,
   icmp_ids,
@@ -302,6 +333,8 @@ const struct mib_array_node icmp = {
 struct mib_list_rootnode ipntomtree_root = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -316,6 +349,8 @@ struct mib_node* const ipntomentry_nodes[4] = {
 const struct mib_array_node ipntomentry = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   4,
   ipntomentry_ids,
@@ -327,6 +362,8 @@ struct mib_node* ipntomtable_node = (struct mib_node* const)&ipntomentry;
 struct mib_ram_array_node ipntomtable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
   0,
   &ipntomtable_id,
@@ -337,6 +374,8 @@ struct mib_ram_array_node ipntomtable = {
 struct mib_list_rootnode iprtetree_root = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -356,6 +395,8 @@ struct mib_node* const iprteentry_nodes[13] = {
 const struct mib_array_node iprteentry = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   13,
   iprteentry_ids,
@@ -367,6 +408,8 @@ struct mib_node* iprtetable_node = (struct mib_node* const)&iprteentry;
 struct mib_ram_array_node iprtetable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
   0,
   &iprtetable_id,
@@ -377,6 +420,8 @@ struct mib_ram_array_node iprtetable = {
 struct mib_list_rootnode ipaddrtree_root = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -394,6 +439,8 @@ struct mib_node* const ipaddrentry_nodes[5] = {
 const struct mib_array_node ipaddrentry = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   5,
   ipaddrentry_ids,
@@ -405,6 +452,8 @@ struct mib_node* ipaddrtable_node = (struct mib_node* const)&ipaddrentry;
 struct mib_ram_array_node ipaddrtable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
   0,
   &ipaddrtable_id,
@@ -415,6 +464,8 @@ struct mib_ram_array_node ipaddrtable = {
 const mib_scalar_node ip_scalar = {
   &ip_get_object_def,
   &ip_get_value,
+  &ip_set_test,
+  &noleafs_set_value,
   MIB_NODE_SC,
   0
 };
@@ -436,6 +487,8 @@ struct mib_node* const ip_nodes[23] = {
 const struct mib_array_node ip = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   23,
   ip_ids,
@@ -446,6 +499,8 @@ const struct mib_array_node ip = {
 struct mib_list_rootnode arptree_root = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -461,6 +516,8 @@ struct mib_node* const atentry_nodes[3] = {
 const struct mib_array_node atentry = {
   &noleafs_get_object_def,
   &noleafs_get_value, 
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   3,
   atentry_ids,
@@ -472,6 +529,8 @@ struct mib_node* const attable_node = (struct mib_node* const)&atentry;
 const struct mib_array_node attable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   1,
   &attable_id,
@@ -484,6 +543,8 @@ struct mib_node* at_node = (struct mib_node* const)&attable;
 struct mib_ram_array_node at = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
   0,
   &at_id,
@@ -494,6 +555,8 @@ struct mib_ram_array_node at = {
 struct mib_list_rootnode iflist_root = {
   &ifentry_get_object_def,
   &ifentry_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_LR,
   0,
   NULL,
@@ -517,6 +580,8 @@ struct mib_node* const ifentry_nodes[22] = {
 const struct mib_array_node ifentry = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   22,
   ifentry_ids,
@@ -528,6 +593,8 @@ struct mib_node* iftable_node = (struct mib_node* const)&ifentry;
 struct mib_ram_array_node iftable = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_RA,
   0,
   &iftable_id,
@@ -538,6 +605,8 @@ struct mib_ram_array_node iftable = {
 const mib_scalar_node interfaces_scalar = {
   &interfaces_get_object_def,
   &interfaces_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_SC,
   0
 };
@@ -548,6 +617,8 @@ struct mib_node* const interfaces_nodes[2] = {
 const struct mib_array_node interfaces = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   2,
   interfaces_ids,
@@ -560,6 +631,8 @@ const struct mib_array_node interfaces = {
 const mib_scalar_node sys_tem_scalar = {
   &system_get_object_def,
   &system_get_value,
+  &system_set_test,
+  &system_set_value,
   MIB_NODE_SC,
   0
 };
@@ -574,6 +647,8 @@ struct mib_node* const sys_tem_nodes[7] = {
 const struct mib_array_node sys_tem = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   7,
   sys_tem_ids,
@@ -615,6 +690,8 @@ struct mib_node* const mib2_nodes[MIB2_GROUPS] = {
 const struct mib_array_node mib2 = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   MIB2_GROUPS,
   mib2_ids,
@@ -627,6 +704,8 @@ struct mib_node* const mgmt_nodes[1] = { (struct mib_node* const)&mib2 };
 const struct mib_array_node mgmt = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   1,
   mgmt_ids,
@@ -640,6 +719,8 @@ struct mib_node* const internet_nodes[2] = { (struct mib_node* const)&mgmt, (str
 const struct mib_array_node internet = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   2,
   internet_ids,
@@ -651,6 +732,8 @@ struct mib_node* const internet_nodes[1] = { (struct mib_node* const)&mgmt };
 const struct mib_array_node internet = {
   &noleafs_get_object_def,
   &noleafs_get_value,
+  &noleafs_set_test,
+  &noleafs_set_value,
   MIB_NODE_AR,
   1,
   internet_ids,
@@ -1021,6 +1104,8 @@ void snmp_insert_arpidx_tree(struct netif *ni, struct ip_addr *ip)
               at_rn->get_object_def = ip_ntomentry_get_object_def;
               at_rn->get_value = ip_ntomentry_get_value;
             }
+            at_rn->set_test = noleafs_set_test;
+            at_rn->set_value = noleafs_set_value;
           }
         }
         else
@@ -1226,6 +1311,8 @@ void snmp_insert_ipaddridx_tree(struct netif *ni)
         {
           ipa_rn->get_object_def = ip_addrentry_get_object_def;
           ipa_rn->get_value = ip_addrentry_get_value;
+          ipa_rn->set_test = noleafs_set_test;
+          ipa_rn->set_value = noleafs_set_value;
         }
       }
       else
@@ -1354,6 +1441,8 @@ void snmp_insert_iprteidx_tree(u8_t dflt, struct netif *ni)
           {
             iprte_rn->get_object_def = ip_rteentry_get_object_def;
             iprte_rn->get_value = ip_rteentry_get_value;
+            iprte_rn->set_test = noleafs_set_test;
+            iprte_rn->set_value = noleafs_set_value;
           }
         }
         else
@@ -1678,6 +1767,8 @@ void snmp_insert_udpidx_tree(struct udp_pcb *pcb)
         {
           udp_rn->get_object_def = udpentry_get_object_def;
           udp_rn->get_value = udpentry_get_value;
+          udp_rn->set_test = noleafs_set_test;
+          udp_rn->set_value = noleafs_set_value;
         }
       }
       else
@@ -1940,6 +2031,25 @@ noleafs_get_value(struct obj_def *od, u16_t len, void *value)
   if (value){}
 }
 
+u8_t
+noleafs_set_test(struct obj_def *od, u16_t len, void *value)
+{
+  if (od){}
+  if (len){}
+  if (value){}
+  /* can't set */
+  return 0;
+}
+
+void
+noleafs_set_value(struct obj_def *od, u16_t len, void *value)
+{
+  if (od){}
+  if (len){}
+  if (value){}
+}
+
+
 /**
  * Returns systems object definitions.
  *
@@ -2065,6 +2175,63 @@ system_get_value(struct obj_def *od, u16_t len, void *value)
   };
 }
 
+static u8_t
+system_set_test(struct obj_def *od, u16_t len, void *value)
+{
+  u8_t id, set_ok;
+
+  if (value) {}
+  set_ok = 0;
+  id = od->id_inst_ptr[0];
+  switch (id)
+  {
+    case 4: /* sysContact */
+      if ((syscontact_ptr != syscontact_default) &&
+          (len <= 255))
+      {
+        set_ok = 1;
+      }
+      break;
+    case 5: /* sysName */
+      if ((sysname_ptr != sysname_default) &&
+          (len <= 255))
+      {
+        set_ok = 1;
+      }
+      break;
+    case 6: /* sysLocation */
+      if ((syslocation_ptr != syslocation_default) &&
+          (len <= 255))
+      {
+        set_ok = 1;
+      }
+      break;
+  };
+  return set_ok;
+}
+
+static void
+system_set_value(struct obj_def *od, u16_t len, void *value)
+{
+  u8_t id;
+
+  id = od->id_inst_ptr[0];
+  switch (id)
+  {
+    case 4: /* sysContact */
+      ocstrncpy(syscontact_ptr,value,len);
+      *syscontact_len_ptr = len;
+      break;
+    case 5: /* sysName */
+      ocstrncpy(sysname_ptr,value,len);
+      *sysname_len_ptr = len;
+      break;
+    case 6: /* sysLocation */
+      ocstrncpy(syslocation_ptr,value,len);
+      *syslocation_len_ptr = len;
+      break;
+  };
+}
 
 /**
  * Returns interfaces.ifnumber object definition.
@@ -2530,10 +2697,6 @@ ip_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od)
   }
 }
 
-/** @todo ipForwarding is writeable, but we may return badValue,
-          in lwIP this is a compile-time switch
-          we will also return a badvalue for wring a default TTL
-          which differs from our compile time default */
 static void
 ip_get_value(struct obj_def *od, u16_t len, void *value)
 {
@@ -2677,6 +2840,49 @@ ip_get_value(struct obj_def *od, u16_t len, void *value)
   };
 }
 
+/**
+ * Test ip object value before setting.
+ *
+ * @param od is the object definition
+ * @param len return value space (in bytes)
+ * @param value points to (varbind) space to copy value from.
+ *
+ * @note we allow set if the value matches the hardwired value,
+ *   otherwise return badvalue.
+ */
+static u8_t
+ip_set_test(struct obj_def *od, u16_t len, void *value)
+{
+  u8_t id, set_ok;
+  s32_t *sint_ptr = value;
+
+  if (len) {}
+  set_ok = 0;
+  id = od->id_inst_ptr[0];
+  switch (id)
+  {
+    case 1: /* ipForwarding */
+#if IP_FORWARD
+      /* forwarding */
+      if (*sint_ptr == 1)
+#else
+      /* not-forwarding */
+      if (*sint_ptr == 2)
+#endif
+      {
+        set_ok = 1;
+      }
+      break;
+    case 2: /* ipDefaultTTL */
+      if (*sint_ptr == IP_DEFAULT_TTL)
+      {
+        set_ok = 1;
+      }
+      break;
+  };
+  return set_ok;
+}
+
 static void
 ip_addrentry_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od)
 {
@@ -3723,4 +3929,59 @@ snmp_get_value(struct obj_def *od, u16_t len, void *value)
   };
 }
 
+/**
+ * Test snmp object value before setting.
+ *
+ * @param od is the object definition
+ * @param len return value space (in bytes)
+ * @param value points to (varbind) space to copy value from.
+ */
+static u8_t
+snmp_set_test(struct obj_def *od, u16_t len, void *value)
+{
+  u8_t id, set_ok;
+
+  if (len) {}
+  set_ok = 0;
+  id = od->id_inst_ptr[0];
+  if (id == 30)
+  {
+    /* snmpEnableAuthenTraps */
+    s32_t *sint_ptr = value;
+
+    if (snmpenableauthentraps_ptr != &snmpenableauthentraps_default)
+    {
+      /* we should have writable non-volatile mem here */
+      if ((*sint_ptr == 1) || (*sint_ptr == 2))
+      {
+        set_ok = 1;
+      }
+    }
+    else
+    {
+      /* const or hardwired value */
+      if (*sint_ptr == snmpenableauthentraps_default)
+      {
+        set_ok = 1;
+      }
+    }
+  }
+  return set_ok;
+}
+
+static void
+snmp_set_value(struct obj_def *od, u16_t len, void *value)
+{
+  u8_t id;
+
+  if (len) {}
+  id = od->id_inst_ptr[0];
+  if (id == 30)
+  {
+    /* snmpEnableAuthenTraps */
+    s32_t *sint_ptr = value;
+    *snmpenableauthentraps_ptr = *sint_ptr;
+  }
+}
+
 #endif /* LWIP_SNMP */

src/core/snmp/mib_structs.c

@@ -190,6 +190,8 @@ snmp_mib_lrn_alloc(void)
   {
     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;

src/core/snmp/msg_in.c

@@ -89,7 +89,7 @@ snmp_init(void)
   {
     msg_ps->state = SNMP_MSG_EMPTY;
     msg_ps->error_index = 0;
-    msg_ps->error_status = 0;
+    msg_ps->error_status = SNMP_ES_NOERROR;
     msg_ps++;
   }
   trap_msg.pcb = snmp1_pcb;
@@ -164,10 +164,6 @@ snmp_msg_event(struct snmp_msg_pstat *msg_ps)
     else if (msg_ps->rt == SNMP_ASN1_PDU_SET_REQ)
     {
     }
-    else
-    {
-      /** @todo not a request, return generror?? */
-    }
   }
   else if (msg_ps->state == SNMP_MSG_INTERNAL)
   {
@@ -213,16 +209,12 @@ snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr,
 
       /* accepting request */
       snmp_inc_snmpinpkts();
-      /* register 'protocol control block' used */
+      /* record used 'protocol control block' */
       msg_ps->pcb = pcb;
       /* source address (network order) */
       msg_ps->sip = *addr;
       /* source port (host order (lwIP oddity)) */
       msg_ps->sp = port;
-      /* demultiplex variable bindings */
-      msg_ps->state = SNMP_MSG_DEMUX;
-      /* first variable binding from list to inspect */
-      msg_ps->vb_idx = 0;
       /* read UDP payload length from UDP header */
       payload_len = ntohs(udphdr->len) - UDP_HLEN;
 
@@ -231,12 +223,24 @@ snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr,
 
       /* check total length, version, community, pdu type */
       err_ret = snmp_pdu_header_check(p, payload_ofs, payload_len, &varbind_ofs, msg_ps);
+      if ((msg_ps->rt == SNMP_ASN1_PDU_GET_REQ) ||
+          (msg_ps->rt == SNMP_ASN1_PDU_GET_NEXT_REQ) ||
+          (msg_ps->rt == SNMP_ASN1_PDU_SET_REQ))
+      {
+        /* Only accept requests. (be robust) */
+        err_ret = err_ret;
+      }
+      else
+      {
+        /* Reject response and trap headers as input! */
+        err_ret = ERR_ARG;
+      }
       if (err_ret == ERR_OK)
       {
         LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_recv ok, community %s\n", msg_ps->community));
-
+        
-       /* Builds a list of variable bindings. Copy the varbinds from the pbuf
+        /* Builds a list of variable bindings. Copy the varbinds from the pbuf
-         chain to glue them when these are divided over two or more pbuf's. */
+          chain to glue them when these are divided over two or more pbuf's. */
         err_ret = snmp_pdu_dec_varbindlist(p, varbind_ofs, &varbind_ofs, msg_ps);
         if ((err_ret == ERR_OK) && (msg_ps->invb.count > 0))
         {          
@@ -245,6 +249,13 @@ snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr,
 
           /* we've decoded the incoming message, release input msg now */
           pbuf_free(p);
+          
+          msg_ps->error_status = SNMP_ES_NOERROR;
+          msg_ps->error_index = 0;
+          /* demultiplex variable bindings */
+          msg_ps->state = SNMP_MSG_DEMUX;
+          /* first variable binding from list to inspect */
+          msg_ps->vb_idx = 0;
 
           LWIP_DEBUGF(SNMP_MSG_DEBUG, ("snmp_recv varbind cnt=%"U16_F"\n",(u16_t)msg_ps->invb.count));
 
@@ -361,14 +372,61 @@ snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr,
               msg_ps->error_index = 1 + msg_ps->vb_idx;
             }
           }
-          else
+          else if (msg_ps->rt == SNMP_ASN1_PDU_SET_REQ)
           {
-            /* request != GET */
+            /** test object identifier for .iso.org.dod.internet prefix */
-            /** @todo EXPERIMENTAL dumb echo, this is not how the agent should respond.
+            if (snmp_iso_prefix_tst(msg_ps->invb.head->ident_len, msg_ps->invb.head->ident))
-                This is for test purposes only, do not use this in real world!! */
+            {
-            msg_ps->outvb = msg_ps->invb;
+              mn = snmp_search_tree((struct mib_node*)&internet, msg_ps->invb.head->ident_len - 4,
-            msg_ps->error_status = SNMP_ES_NOERROR;
+                                     msg_ps->invb.head->ident + 4, &object_def);
-            msg_ps->error_index = 0;
+            }
+            else
+            {
+              mn = NULL;
+            }
+            if (mn != NULL)
+            {
+              struct snmp_varbind *vb;
+
+              vb = msg_ps->invb.head;
+              if ((object_def.access == MIB_OBJECT_READ_WRITE) &&
+                  (object_def.asn_type == vb->value_type) &&
+                  (mn->set_test(&object_def,vb->value_len,vb->value) != 0))
+              {
+                 /** @todo change this if we support vb-lists,
+                     first test all vbs, then either set all or give badvalue */
+                 mn->set_value(&object_def,vb->value_len,vb->value);
+                 /** simply echo the input if we can set it */
+                 msg_ps->outvb = msg_ps->invb;
+                 msg_ps->invb.head = NULL;
+                 msg_ps->invb.tail = NULL;
+                 msg_ps->invb.count = 0;
+              }
+              else
+              {
+                /* bad value */
+                /* @todo move used names back from outvb to invb */
+                snmp_varbind_list_free(&msg_ps->outvb);
+                msg_ps->outvb = msg_ps->invb;
+                msg_ps->invb.head = NULL;
+                msg_ps->invb.tail = NULL;
+                msg_ps->invb.count = 0;
+                msg_ps->error_status = SNMP_ES_BADVALUE;
+                msg_ps->error_index = 1 + msg_ps->vb_idx;
+              }
+            }
+            else
+            {
+              /* mn == NULL, noSuchName */
+              /* @todo move used names back from outvb to invb */
+              snmp_varbind_list_free(&msg_ps->outvb);
+              msg_ps->outvb = msg_ps->invb;
+              msg_ps->invb.head = NULL;
+              msg_ps->invb.tail = NULL;
+              msg_ps->invb.count = 0;
+              msg_ps->error_status = SNMP_ES_NOSUCHNAME;
+              msg_ps->error_index = 1 + msg_ps->vb_idx;
+            }
           }
 
 /* when more variable bindings left msg_ps->state = SNMP_MSG_DEMUX */

src/include/lwip/snmp_structs.h

@@ -94,7 +94,10 @@ struct mib_node
   /** returns object value for the given object identifier,
      @note the caller must allocate at least len bytes for the value */
   void (*get_value)(struct obj_def *od, u16_t len, void *value);
-  /** @todo set_value() */
+  /** tests length and/or range BEFORE setting */
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  /** sets object value, only to be called when set_test()  */
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);  
   /** One out of MIB_NODE_AR, MIB_NODE_LR or MIB_NODE_EX */
   const u8_t node_type;
   /* array or max list length */
@@ -111,6 +114,8 @@ struct mib_array_node
   /* inherited "base class" members */
   void (* const get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
   void (* const get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
 
   const u8_t node_type;
   const u16_t maxlength;
@@ -127,6 +132,8 @@ struct mib_ram_array_node
   /* inherited "base class" members */
   void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
   void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
 
   u8_t node_type;
   u16_t maxlength;
@@ -151,6 +158,8 @@ struct mib_list_rootnode
   /* inherited "base class" members */
   void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
   void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
 
   u8_t node_type;
   u16_t maxlength;
@@ -169,6 +178,8 @@ struct mib_external_node
   /* inherited "base class" members */
   void (*get_object_def)(u8_t ident_len, s32_t *ident, struct obj_def *od);
   void (*get_value)(struct obj_def *od, u16_t len, void *value);
+  u8_t (*set_test)(struct obj_def *od, u16_t len, void *value);
+  void (*set_value)(struct obj_def *od, u16_t len, void *value);
 
   u8_t node_type;
   u16_t maxlength;
@@ -192,6 +203,8 @@ extern const struct mib_array_node internet;
 /** dummy function pointers for non-leaf MIB nodes from mib2.c */
 void noleafs_get_object_def(u8_t ident_len, s32_t *ident, struct obj_def *od);
 void noleafs_get_value(struct obj_def *od, u16_t len, void *value);
+u8_t noleafs_set_test(struct obj_def *od, u16_t len, void *value);
+void noleafs_set_value(struct obj_def *od, u16_t len, void *value);
 
 void snmp_oidtoip(s32_t *ident, struct ip_addr *ip);
 void snmp_iptooid(struct ip_addr *ip, s32_t *ident);