Add taint-tracking for crypto/tls package

Author: gagliardetto

ql/src/semmle/go/frameworks/Stdlib.qll

@@ -16,6 +16,7 @@ import semmle.go.frameworks.stdlib.Fmt
 import semmle.go.frameworks.stdlib.Crypto
 import semmle.go.frameworks.stdlib.CryptoCipher
 import semmle.go.frameworks.stdlib.CryptoRsa
+import semmle.go.frameworks.stdlib.CryptoTls
 import semmle.go.frameworks.stdlib.Mime
 import semmle.go.frameworks.stdlib.MimeMultipart
 import semmle.go.frameworks.stdlib.MimeQuotedprintable

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

@@ -0,0 +1,58 @@
+/**
+ * Provides classes modeling security-relevant aspects of the `crypto/tls` package.
+ */
+
+import go
+
+/** Provides models of commonly used functions in the `crypto/tls` package. */
+module CryptoTls {
+  private class FunctionModels extends TaintTracking::FunctionModel {
+    FunctionInput inp;
+    FunctionOutput outp;
+
+    FunctionModels() {
+      // signature: func Client(conn net.Conn, config *Config) *Conn
+      hasQualifiedName("crypto/tls", "Client") and
+      (
+        inp.isParameter(0) and outp.isResult()
+        or
+        inp.isResult() and outp.isParameter(0)
+      )
+      or
+      // signature: func NewListener(inner net.Listener, config *Config) net.Listener
+      hasQualifiedName("crypto/tls", "NewListener") and
+      (inp.isParameter(0) and outp.isResult())
+      or
+      // signature: func Server(conn net.Conn, config *Config) *Conn
+      hasQualifiedName("crypto/tls", "Server") and
+      (
+        inp.isParameter(0) and outp.isResult()
+        or
+        inp.isResult() and outp.isParameter(0)
+      )
+    }
+
+    override predicate hasTaintFlow(FunctionInput input, FunctionOutput output) {
+      input = inp and output = outp
+    }
+  }
+
+  private class MethodModels extends TaintTracking::FunctionModel, Method {
+    FunctionInput inp;
+    FunctionOutput outp;
+
+    MethodModels() {
+      // signature: func (*Conn).Read(b []byte) (int, error)
+      this.hasQualifiedName("crypto/tls", "Conn", "Read") and
+      (inp.isReceiver() and outp.isParameter(0))
+      or
+      // signature: func (*Conn).Write(b []byte) (int, error)
+      this.hasQualifiedName("crypto/tls", "Conn", "Write") and
+      (inp.isParameter(0) and outp.isReceiver())
+    }
+
+    override predicate hasTaintFlow(FunctionInput input, FunctionOutput output) {
+      input = inp and output = outp
+    }
+  }
+}