P4TC - Add permission annotations to tables (#4610)

* Implementation to add permisson annotation 'tc_acl' to P4Tables.

* Update testcases and Fix cpplint issue

* Addressed comments

* Addressed comments

* Change Default Permission

backends/tc/backend.cpp

@@ -514,6 +514,110 @@ void ConvertToBackendIR::updateDefaultHitAction(const IR::P4Table *t, IR::TCTabl
     }
 }
 
+void ConvertToBackendIR::updateAddOnMissTable(const IR::P4Table *t) {
+    auto tblname = t->name.originalName;
+    for (auto table : tcPipeline->tableDefs) {
+        if (table->tableName == tblname) {
+            add_on_miss_tables.push_back(t);
+            auto tableDefinition = ((IR::TCTable *)table);
+            tableDefinition->setTableAddOnMiss();
+            tableDefinition->setTablePermission(HandleTableAccessPermission(t));
+        }
+    }
+}
+
+unsigned ConvertToBackendIR::GetAccessNumericValue(cstring access) {
+    unsigned value = 0;
+    for (auto s : access) {
+        unsigned mask = 0;
+        switch (s) {
+            case 'C':
+                mask = 1 << 6;
+                break;
+            case 'R':
+                mask = 1 << 5;
+                break;
+            case 'U':
+                mask = 1 << 4;
+                break;
+            case 'D':
+                mask = 1 << 3;
+                break;
+            case 'X':
+                mask = 1 << 2;
+                break;
+            case 'P':
+                mask = 1 << 1;
+                break;
+            case 'S':
+                mask = 1;
+                break;
+            default:
+                ::error(ErrorType::ERR_INVALID,
+                        "tc_acl annotation cannot have '%1%' in access permisson", s);
+        }
+        value |= mask;
+    }
+    return value;
+}
+
+cstring ConvertToBackendIR::HandleTableAccessPermission(const IR::P4Table *t) {
+    bool IsTableAddOnMiss = false;
+    cstring control_path, data_path;
+    for (auto table : add_on_miss_tables) {
+        if (table->name.originalName == t->name.originalName) {
+            IsTableAddOnMiss = true;
+        }
+    }
+    auto find = tablePermissions.find(t->name.originalName);
+    if (find != tablePermissions.end()) {
+        auto paths = tablePermissions[t->name.originalName];
+        control_path = paths->first;
+        data_path = paths->second;
+    }
+    // Default access value of Control_path and Data_Path
+    if (control_path.isNullOrEmpty()) {
+        control_path = IsTableAddOnMiss ? DEFAULT_ADD_ON_MISS_TABLE_CONTROL_PATH_ACCESS
+                                        : DEFAULT_TABLE_CONTROL_PATH_ACCESS;
+    }
+    if (data_path.isNullOrEmpty()) {
+        data_path = IsTableAddOnMiss ? DEFAULT_ADD_ON_MISS_TABLE_DATA_PATH_ACCESS
+                                     : DEFAULT_TABLE_DATA_PATH_ACCESS;
+    }
+
+    if (IsTableAddOnMiss) {
+        auto access = data_path.find('C');
+        if (!access) {
+            ::warning(
+                ErrorType::WARN_INVALID,
+                "Add on miss table '%1%' should have 'create' access permissons for data path.",
+                t->name.originalName);
+        }
+    }
+    auto access_cp = GetAccessNumericValue(control_path);
+    auto access_dp = GetAccessNumericValue(data_path);
+    auto access_permisson = (access_cp << 7) | access_dp;
+    std::stringstream value;
+    value << "0x" << std::hex << access_permisson;
+    return value.str().c_str();
+}
+
+std::pair<cstring, cstring> *ConvertToBackendIR::GetAnnotatedAccessPath(
+    const IR::Annotation *anno) {
+    cstring control_path, data_path;
+    if (anno) {
+        auto expr = anno->expr[0];
+        if (auto typeLiteral = expr->to<IR::StringLiteral>()) {
+            auto permisson_str = typeLiteral->value;
+            auto char_pos = permisson_str.find(":");
+            control_path = permisson_str.before(char_pos);
+            data_path = permisson_str.substr(char_pos - permisson_str.begin() + 1);
+        }
+    }
+    auto paths = new std::pair<cstring, cstring>(control_path, data_path);
+    return paths;
+}
+
 void ConvertToBackendIR::postorder(const IR::P4Table *t) {
     if (t != nullptr) {
         tableCount++;
@@ -551,17 +655,21 @@ void ConvertToBackendIR::postorder(const IR::P4Table *t) {
         tableKeysizeList.emplace(tId, keySize);
         auto annoList = t->getAnnotations()->annotations;
         for (auto anno : annoList) {
-            if (anno->name != ParseTCAnnotations::numMask) continue;
-            auto expr = anno->expr[0];
-            if (auto val = expr->to<IR::Constant>()) {
-                tableDefinition->setNumMask(val->asUint64());
-            } else {
-                ::error(ErrorType::ERR_INVALID,
-                        "nummask annotation cannot have '%1%' as value. Only integer "
-                        "constants are allowed",
-                        expr);
+            if (anno->name == ParseTCAnnotations::tc_acl) {
+                tablePermissions.emplace(t->name.originalName, GetAnnotatedAccessPath(anno));
+            } else if (anno->name == ParseTCAnnotations::numMask) {
+                auto expr = anno->expr[0];
+                if (auto val = expr->to<IR::Constant>()) {
+                    tableDefinition->setNumMask(val->asUint64());
+                } else {
+                    ::error(ErrorType::ERR_INVALID,
+                            "nummask annotation cannot have '%1%' as value. Only integer "
+                            "constants are allowed",
+                            expr);
+                }
             }
         }
+        tableDefinition->setTablePermission(HandleTableAccessPermission(t));
         auto actionlist = t->getActionList();
         for (auto action : actionlist->actionList) {
             for (auto actionDef : tcPipeline->actionDefs) {

backends/tc/backend.h

@@ -62,6 +62,8 @@ class ConvertToBackendIR : public Inspector {
     ordered_map<unsigned, cstring> tableIDList;
     ordered_map<unsigned, cstring> actionIDList;
     ordered_map<unsigned, unsigned> tableKeysizeList;
+    safe_vector<const IR::P4Table *> add_on_miss_tables;
+    ordered_map<cstring, std::pair<cstring, cstring> *> tablePermissions;
 
  public:
     ConvertToBackendIR(const IR::ToplevelBlock *tlb, IR::TCPipeline *pipe, P4::ReferenceMap *refMap,
@@ -89,13 +91,10 @@ class ConvertToBackendIR : public Inspector {
     unsigned getActionId(cstring actionName) const;
     unsigned getTableKeysize(unsigned tableId) const;
     cstring externalName(const IR::IDeclaration *declaration) const;
-    void updateAddOnMissTable(cstring tblname) const {
-        for (auto table : tcPipeline->tableDefs) {
-            if (table->tableName == tblname) {
-                ((IR::TCTable *)table)->setTableAddOnMiss();
-            }
-        }
-    }
+    cstring HandleTableAccessPermission(const IR::P4Table *t);
+    std::pair<cstring, cstring> *GetAnnotatedAccessPath(const IR::Annotation *anno);
+    unsigned GetAccessNumericValue(cstring access);
+    void updateAddOnMissTable(const IR::P4Table *t);
 };
 
 class Extern {

backends/tc/ebpfCodeGen.cpp

@@ -1534,7 +1534,6 @@ void ControlBodyTranslatorPNA::ValidateAddOnMissMissAction(const IR::P4Action *a
                 act);
     }
     const IR::P4Table *t = table->table->container;
-    cstring tblname = t->name.originalName;
     const IR::Expression *defaultAction = t->getDefaultAction();
     CHECK_NULL(defaultAction);
     auto defaultActionName = table->getActionNameExpression(defaultAction);
@@ -1548,7 +1547,7 @@ void ControlBodyTranslatorPNA::ValidateAddOnMissMissAction(const IR::P4Action *a
                   "add_entry extern can only be used in an action"
                   " of a table with property add_on_miss equals to true.");
     }
-    tcIR->updateAddOnMissTable(tblname);
+    ((ConvertToBackendIR *)tcIR)->updateAddOnMissTable(t);
 }
 
 void ControlBodyTranslatorPNA::processFunction(const P4::ExternFunction *function) {

backends/tc/introspection.cpp

@@ -37,6 +37,7 @@ void IntrospectionGenerator::collectTableInfo() {
         tableInfo->id = table->tableID;
         tableInfo->name = table->controlName + "/" + table->tableName;
         tableInfo->tentries = table->tableEntriesCount;
+        tableInfo->permissions = table->permissions;
         tableInfo->numMask = table->numMask;
         if (table->keySize != 0) {
             tableInfo->keysize = table->keySize;
@@ -240,6 +241,7 @@ Util::JsonObject *IntrospectionGenerator::genTableInfo(struct TableAttributes *t
     tableJson->emplace("name", tbl->name);
     tableJson->emplace("id", tbl->id);
     tableJson->emplace("tentries", tbl->tentries);
+    tableJson->emplace("permissions", tbl->permissions);
     tableJson->emplace("nummask", tbl->numMask);
     if (tbl->keysize != 0) {
         tableJson->emplace("keysize", tbl->keysize);

backends/tc/introspection.h

@@ -97,6 +97,7 @@ struct ActionAttributes {
 
 struct TableAttributes {
     cstring name;
+    cstring permissions;
     unsigned int id;
     unsigned int tentries;
     unsigned int numMask;
@@ -106,6 +107,7 @@ struct TableAttributes {
     safe_vector<struct ActionAttributes *> actions;
     TableAttributes() {
         name = nullptr;
+        permissions = nullptr;
         id = 0;
         tentries = 0;
         numMask = 0;

backends/tc/tc.def

@@ -228,6 +228,7 @@ class TCTable {
     cstring tableName;
     cstring controlName;
     cstring pipelineName;
+    cstring permissions;
     unsigned keySize;
     unsigned tableEntriesCount;
     unsigned numMask;
@@ -244,6 +245,9 @@ class TCTable {
     ordered_map<TCAction, unsigned> actionList;
     safe_vector<TCEntry> const_entries;
 
+    void setTablePermission(cstring p) {
+        permissions = p;
+    }
     void setKeySize(unsigned k) {
         keySize = k;
     }
@@ -326,12 +330,10 @@ class TCTable {
         tcTable += "\n\ttype " + printMatchType(matchType) + " \\";
         tcTable += "\n\tkeysz " + Util::toString(keySize);
         tcTable += " nummasks " + Util::toString(numMask);
+        tcTable += " permissions " + Util::toString(permissions);
         tcTable += " tentries " + Util::toString(tableEntriesCount);
-        if (isTableAddOnMiss) {
-            tcTable += " permissions 0x3DE6";
-            if(timerProfiles > defaultTimerProfiles) {
-                tcTable += " num_timer_profiles " + Util::toString(timerProfiles);
-            }
+        if (isTableAddOnMiss && timerProfiles > defaultTimerProfiles) {
+            tcTable += " num_timer_profiles " + Util::toString(timerProfiles);
         }
 
         if (!actionList.empty()) {

backends/tc/tcAnnotations.cpp

@@ -23,5 +23,6 @@ const cstring ParseTCAnnotations::defaultHitConst = "default_hit_const";
 const cstring ParseTCAnnotations::tcType = "tc_type";
 const cstring ParseTCAnnotations::numMask = "nummask";
 const cstring ParseTCAnnotations::tcMayOverride = "tc_may_override";
+const cstring ParseTCAnnotations::tc_acl = "tc_acl";
 
 }  // namespace TC

backends/tc/tcAnnotations.h

@@ -30,12 +30,13 @@ class ParseTCAnnotations : public P4::ParseAnnotations {
     static const cstring tcType;
     static const cstring numMask;
     static const cstring tcMayOverride;
+    static const cstring tc_acl;
     ParseTCAnnotations()
         : P4::ParseAnnotations(
               "TC", true,
               {PARSE_EMPTY(defaultHit), PARSE_EMPTY(defaultHitConst),
                PARSE_CONSTANT_OR_STRING_LITERAL(tcType), PARSE_CONSTANT_OR_STRING_LITERAL(numMask),
-               PARSE_EMPTY(tcMayOverride)}) {}
+               PARSE_EMPTY(tcMayOverride), PARSE_CONSTANT_OR_STRING_LITERAL(tc_acl)}) {}
 };
 
 }  // namespace TC

backends/tc/tc_defines.h

@@ -27,6 +27,12 @@ inline constexpr auto DEFAULT_METADATA_ID = 1;
 inline constexpr auto BITWIDTH = 32;
 inline constexpr auto DEFAULT_TIMER_PROFILES = 4;
 
+// Default Access Permissons
+inline constexpr auto DEFAULT_TABLE_CONTROL_PATH_ACCESS = "CRUDPS";
+inline constexpr auto DEFAULT_TABLE_DATA_PATH_ACCESS = "RX";
+inline constexpr auto DEFAULT_ADD_ON_MISS_TABLE_CONTROL_PATH_ACCESS = "CRUDPS";
+inline constexpr auto DEFAULT_ADD_ON_MISS_TABLE_DATA_PATH_ACCESS = "CRXP";
+
 // Supported data types.
 inline constexpr auto BIT_TYPE = 0;
 inline constexpr auto DEV_TYPE = 1;

testdata/p4tc_samples/add_entry_1_example.p4

@@ -90,7 +90,7 @@ control MainControlImpl(
         drop_packet();
     }
 
-    table ipv4_tbl_1 {
+    @tc_acl("CRUS:CRXP") table ipv4_tbl_1 {
         key = {
             hdr.ipv4.dstAddr : exact @tc_type ("ipv4");
             istd.input_port : exact;