Merge pull request #1000 from NetSys/remove_entry

BPF: commands for removing a BPF rule

Author: melvinw

core/modules/bpf.cc

@@ -51,6 +51,8 @@
 const Commands BPF::cmds = {
     {"add", "BPFArg", MODULE_CMD_FUNC(&BPF::CommandAdd),
      Command::THREAD_UNSAFE},
+    {"delete", "BPFArg", MODULE_CMD_FUNC(&BPF::CommandDelete),
+     Command::THREAD_UNSAFE},
     {"clear", "EmptyArg", MODULE_CMD_FUNC(&BPF::CommandClear),
      Command::THREAD_UNSAFE},
     {"get_initial_arg", "EmptyArg", MODULE_CMD_FUNC(&BPF::GetInitialArg),
@@ -125,6 +127,24 @@ CommandResponse BPF::CommandAdd(const bess::pb::BPFArg &arg) {
   return CommandSuccess();
 }
 
+CommandResponse BPF::CommandDelete(const bess::pb::BPFArg &arg) {
+  for (const auto &f : arg.filters()) {
+    if (f.gate() < 0 || f.gate() >= MAX_GATES) {
+      return CommandFailure(EINVAL, "Invalid gate");
+    }
+
+    for (auto i = filters_.begin(); i != filters_.end(); ++i) {
+      if (f.priority() == i->priority && f.gate() == i->gate &&
+          f.filter() == i->exp) {
+        filters_.erase(i);
+        break;
+      }
+    }
+  }
+
+  return CommandSuccess();
+}
+
 CommandResponse BPF::CommandClear(const bess::pb::EmptyArg &) {
   DeInit();
   return CommandSuccess();

core/modules/bpf.h

@@ -54,6 +54,7 @@ class BPF final : public Module {
 
   CommandResponse GetInitialArg(const bess::pb::EmptyArg &);
   CommandResponse CommandAdd(const bess::pb::BPFArg &arg);
+  CommandResponse CommandDelete(const bess::pb::BPFArg &arg);
   CommandResponse CommandClear(const bess::pb::EmptyArg &arg);
 
  private: