Fix exception thrown by boost in MaskToPrefix

Boost Ip4Address() takes unsigned long as argument. If the address
passed is greater than 0xFFFFFFFF, it throws exception. Method
MaskToPrefix has potential to pass values greater than 0xFFFFFFFF.

Renamed MaskToPrefix to PrefixToIpAddress and moved to base/util.h.
The new method uses uint32_t for mask. This ensures the value is
never greater than 0xFFFFFFFF

Change-Id: I64a69c59e7902142e68e09ecef8964a3d79933f7
Closes-Bug: #1390594

src/base/task.cc

@@ -234,10 +234,12 @@ tbb::task *TaskImpl::execute() {
         // information from the core.
         static std::string what = e.what();
 
-        LOG(DEBUG, "!!!! ERROR !!!! Task caught fatal exception: " << what);
+        LOG(DEBUG, "!!!! ERROR !!!! Task caught fatal exception: " << what
+            << " TaskImpl: " << this);
         assert(0);
     } catch (...) {
-        LOG(DEBUG, "!!!! ERROR !!!! Task caught fatal unknown exception");
+        LOG(DEBUG, "!!!! ERROR !!!! Task caught fatal unknown exception"
+            << " TaskImpl: " << this);
         assert(0);
     }
 

src/base/util.h

@@ -240,6 +240,17 @@ static inline bool ValidateIPAddressString(std::string ip_address_str,
     return true;
 }
 
+static inline IpAddress PrefixToIpNetmask(uint32_t prefix_len) {
+    uint32_t mask;
+
+    if (prefix_len == 0) {
+        mask = 0;
+    } else {
+        mask = (~((1 << (32 - prefix_len)) - 1));
+    }
+    return IpAddress(Ip4Address(mask));
+}
+
 static inline uint32_t NetmaskToPrefix(uint32_t netmask) {
     uint32_t count = 0;
 

src/vnsw/agent/filter/acl.cc

@@ -199,13 +199,6 @@ DBTableBase *AclTable::CreateTable(DB *db, const std::string &name) {
     return acl_table_;
 }
 
-static inline IpAddress MaskToPrefix(int prefix_len) {
-    if (prefix_len == 0 )
-        return (IpAddress(Ip4Address(~((unsigned int) -1))));
-    else
-        return (IpAddress(Ip4Address(~((1 << (32 - prefix_len)) - 1))));
-}
-
 static void AclEntryObjectTrace(AclEntrySandeshData &ace_sandesh, AclEntrySpec &ace_spec)
 {
     ace_sandesh.set_ace_id(integerToString(ace_spec.id));
@@ -738,7 +731,7 @@ bool AclEntrySpec::Populate(const MatchConditionType *match_condition) {
             return false;
         }
         src_ip_plen = st.ip_prefix_len;
-        src_ip_mask = MaskToPrefix(st.ip_prefix_len);
+        src_ip_mask = PrefixToIpNetmask(st.ip_prefix_len);
         src_addr_type = AddressMatch::IP_ADDR;
     } else if (match_condition->src_address.virtual_network.size()) {
         std::string nt;
@@ -766,7 +759,7 @@ bool AclEntrySpec::Populate(const MatchConditionType *match_condition) {
             return false;
         }
         dst_ip_plen = st.ip_prefix_len;
-        dst_ip_mask = MaskToPrefix(st.ip_prefix_len);
+        dst_ip_mask = PrefixToIpNetmask(st.ip_prefix_len);
         dst_addr_type = AddressMatch::IP_ADDR;
     } else if (match_condition->dst_address.virtual_network.size()) {
         std::string nt;