Extend MarshalingFunction and UnmarshalingFunction with encoding/pem

ql/src/semmle/go/frameworks/stdlib/EncodingPem.qll

@@ -6,6 +6,39 @@ import go
 
 /** Provides models of commonly used functions in the `encoding/pem` package. */
 module EncodingPem {
+  /** The `Encode` function in the `encoding/pem` package. */
+  private class EncodeFunction extends MarshalingFunction::Range {
+    EncodeFunction() { hasQualifiedName("encoding/pem", "Encode") }
+
+    override FunctionInput getAnInput() { result.isParameter(1) }
+
+    override FunctionOutput getOutput() { result.isParameter(0) }
+
+    override string getFormat() { result = "PEM" }
+  }
+
+  /** The `EncodeToMemory` function in the `encoding/pem` package. */
+  private class EncodeToMemoryFunction extends MarshalingFunction::Range {
+    EncodeToMemoryFunction() { hasQualifiedName("encoding/pem", "EncodeToMemory") }
+
+    override FunctionInput getAnInput() { result.isParameter(0) }
+
+    override FunctionOutput getOutput() { result.isResult() }
+
+    override string getFormat() { result = "PEM" }
+  }
+
+  /** The `Decode` function in the `encoding/pem` package. */
+  private class UnmarshalFunction extends UnmarshalingFunction::Range {
+    UnmarshalFunction() { hasQualifiedName("encoding/pem", "Decode") }
+
+    override FunctionInput getAnInput() { result.isParameter(0) }
+
+    override FunctionOutput getOutput() { result.isResult(0) }
+
+    override string getFormat() { result = "PEM" }
+  }
+
   private class FunctionModels extends TaintTracking::FunctionModel {
     FunctionInput inp;
     FunctionOutput outp;