Merge pull request github#5864 from RasmusWL/some-framework-modeling

Approved by tausbn

Author: codeql-ci

docs/codeql/support/reusables/frameworks.rst

@@ -157,8 +157,11 @@ Python built-in support
    Tornado, Web framework
    PyYAML, Serialization
    dill, Serialization
+   simplejson, Serialization
+   ujson, Serialization
    fabric, Utility library
    invoke, Utility library
+   idna, Utility library
    mysql-connector-python, Database
    MySQLdb, Database
    psycopg2, Database

python/change-notes/2021-05-10-idna-add-modeling.md

@@ -0,0 +1,2 @@
+lgtm,codescanning
+* Added modeling of the PyPI package `idna`, for encoding/decoding Internationalised Domain Names in Applications.

python/change-notes/2021-05-10-simplejson-add-modeling.md

@@ -0,0 +1,2 @@
+lgtm,codescanning
+* Added modeling of the PyPI package `simplejson`.

python/change-notes/2021-05-10-ujson-add-modeling.md

@@ -0,0 +1,2 @@
+lgtm,codescanning
+* Added modeling of the PyPI package `ujson`.

python/ql/src/semmle/python/Frameworks.qll

@@ -2,17 +2,22 @@
  * Helper file that imports all framework modeling.
  */
 
+// If you add modeling of a new framework/library, remember to add it it to the docs in
+// `docs/codeql/support/reusables/frameworks.rst`
 private import semmle.python.frameworks.Cryptodome
 private import semmle.python.frameworks.Cryptography
 private import semmle.python.frameworks.Dill
 private import semmle.python.frameworks.Django
 private import semmle.python.frameworks.Fabric
 private import semmle.python.frameworks.Flask
+private import semmle.python.frameworks.Idna
 private import semmle.python.frameworks.Invoke
 private import semmle.python.frameworks.MysqlConnectorPython
 private import semmle.python.frameworks.MySQLdb
 private import semmle.python.frameworks.Psycopg2
 private import semmle.python.frameworks.PyMySQL
+private import semmle.python.frameworks.Simplejson
 private import semmle.python.frameworks.Stdlib
 private import semmle.python.frameworks.Tornado
+private import semmle.python.frameworks.Ujson
 private import semmle.python.frameworks.Yaml

python/ql/src/semmle/python/frameworks/Idna.qll

@@ -0,0 +1,40 @@
+/**
+ * Provides classes modeling security-relevant aspects of the `idna` PyPI package.
+ * See https://pypi.org/project/idna/.
+ */
+
+private import python
+private import semmle.python.dataflow.new.DataFlow
+private import semmle.python.dataflow.new.TaintTracking
+private import semmle.python.Concepts
+private import semmle.python.ApiGraphs
+
+/**
+ * Provides models for the `idna` PyPI package.
+ * See https://pypi.org/project/idna/.
+ */
+private module IdnaModel {
+  /** A call to `idna.encode`. */
+  private class IdnaEncodeCall extends Encoding::Range, DataFlow::CallCfgNode {
+    IdnaEncodeCall() { this = API::moduleImport("idna").getMember("encode").getACall() }
+
+    override DataFlow::Node getAnInput() { result = [this.getArg(0), this.getArgByName("s")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "IDNA" }
+  }
+
+  /** A call to `idna.decode`. */
+  private class IdnaDecodeCall extends Decoding::Range, DataFlow::CallCfgNode {
+    IdnaDecodeCall() { this = API::moduleImport("idna").getMember("decode").getACall() }
+
+    override DataFlow::Node getAnInput() { result = [this.getArg(0), this.getArgByName("s")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "IDNA" }
+
+    override predicate mayExecuteInput() { none() }
+  }
+}

python/ql/src/semmle/python/frameworks/Simplejson.qll

@@ -0,0 +1,84 @@
+/**
+ * Provides classes modeling security-relevant aspects of the `simplejson` PyPI package.
+ * See https://simplejson.readthedocs.io/en/latest/.
+ */
+
+private import python
+private import semmle.python.dataflow.new.DataFlow
+private import semmle.python.dataflow.new.TaintTracking
+private import semmle.python.Concepts
+private import semmle.python.ApiGraphs
+
+/**
+ * Provides models for the `simplejson` PyPI package.
+ * See https://simplejson.readthedocs.io/en/latest/.
+ */
+private module SimplejsonModel {
+  /**
+   * A call to `simplejson.dumps`.
+   *
+   * See https://simplejson.readthedocs.io/en/latest/#simplejson.dumps
+   */
+  private class SimplejsonDumpsCall extends Encoding::Range, DataFlow::CallCfgNode {
+    SimplejsonDumpsCall() { this = API::moduleImport("simplejson").getMember("dumps").getACall() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("obj")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+  }
+
+  /**
+   * A call to `simplejson.dump`.
+   *
+   * See https://simplejson.readthedocs.io/en/latest/#simplejson.dump
+   */
+  private class SimplejsonDumpCall extends Encoding::Range, DataFlow::CallCfgNode {
+    SimplejsonDumpCall() { this = API::moduleImport("simplejson").getMember("dump").getACall() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("obj")] }
+
+    override DataFlow::Node getOutput() {
+      result.(DataFlow::PostUpdateNode).getPreUpdateNode() in [
+          this.getArg(1), this.getArgByName("fp")
+        ]
+    }
+
+    override string getFormat() { result = "JSON" }
+  }
+
+  /**
+   * A call to `simplejson.loads`.
+   *
+   * See https://simplejson.readthedocs.io/en/latest/#simplejson.loads
+   */
+  private class SimplejsonLoadsCall extends Decoding::Range, DataFlow::CallCfgNode {
+    SimplejsonLoadsCall() { this = API::moduleImport("simplejson").getMember("loads").getACall() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("s")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+
+    override predicate mayExecuteInput() { none() }
+  }
+
+  /**
+   * A call to `simplejson.load`.
+   *
+   * See https://simplejson.readthedocs.io/en/latest/#simplejson.load
+   */
+  private class SimplejsonLoadCall extends Decoding::Range, DataFlow::CallCfgNode {
+    SimplejsonLoadCall() { this = API::moduleImport("simplejson").getMember("load").getACall() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("fp")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+
+    override predicate mayExecuteInput() { none() }
+  }
+}

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

@@ -511,7 +511,23 @@ private module Stdlib {
 
     override predicate mayExecuteInput() { none() }
 
-    override DataFlow::Node getAnInput() { result.asCfgNode() = node.getArg(0) }
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("s")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+  }
+
+  /**
+   * A call to `json.load`
+   * See https://docs.python.org/3/library/json.html#json.load
+   */
+  private class JsonLoadCall extends Decoding::Range, DataFlow::CallCfgNode {
+    JsonLoadCall() { this = json().getMember("load").getACall() }
+
+    override predicate mayExecuteInput() { none() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("fp")] }
 
     override DataFlow::Node getOutput() { result = this }
 
@@ -525,13 +541,31 @@ private module Stdlib {
   private class JsonDumpsCall extends Encoding::Range, DataFlow::CallCfgNode {
     JsonDumpsCall() { this = json().getMember("dumps").getACall() }
 
-    override DataFlow::Node getAnInput() { result.asCfgNode() = node.getArg(0) }
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("obj")] }
 
     override DataFlow::Node getOutput() { result = this }
 
     override string getFormat() { result = "JSON" }
   }
 
+  /**
+   * A call to `json.dump`
+   * See https://docs.python.org/3/library/json.html#json.dump
+   */
+  private class JsonDumpCall extends Encoding::Range, DataFlow::CallCfgNode {
+    JsonDumpCall() { this = json().getMember("dump").getACall() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("obj")] }
+
+    override DataFlow::Node getOutput() {
+      result.(DataFlow::PostUpdateNode).getPreUpdateNode() in [
+          this.getArg(1), this.getArgByName("fp")
+        ]
+    }
+
+    override string getFormat() { result = "JSON" }
+  }
+
   // ---------------------------------------------------------------------------
   // cgi
   // ---------------------------------------------------------------------------

python/ql/src/semmle/python/frameworks/Ujson.qll

@@ -0,0 +1,76 @@
+/**
+ * Provides classes modeling security-relevant aspects of the `ujson` PyPI package.
+ * See https://pypi.org/project/ujson/.
+ */
+
+private import python
+private import semmle.python.dataflow.new.DataFlow
+private import semmle.python.dataflow.new.TaintTracking
+private import semmle.python.Concepts
+private import semmle.python.ApiGraphs
+
+/**
+ * Provides models for the `ujson` PyPI package.
+ * See https://pypi.org/project/ujson/.
+ */
+private module UjsonModel {
+  /**
+   * A call to `usjon.dumps` or `ujson.encode`.
+   */
+  private class UjsonDumpsCall extends Encoding::Range, DataFlow::CallCfgNode {
+    UjsonDumpsCall() { this = API::moduleImport("ujson").getMember(["dumps", "encode"]).getACall() }
+
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("obj")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+  }
+
+  /**
+   * A call to `ujson.dump`.
+   */
+  private class UjsonDumpCall extends Encoding::Range, DataFlow::CallCfgNode {
+    UjsonDumpCall() { this = API::moduleImport("ujson").getMember("dump").getACall() }
+
+    override DataFlow::Node getAnInput() { result = this.getArg(0) }
+
+    override DataFlow::Node getOutput() {
+      result.(DataFlow::PostUpdateNode).getPreUpdateNode() = this.getArg(1)
+    }
+
+    override string getFormat() { result = "JSON" }
+  }
+
+  /**
+   * A call to `ujson.loads` or `ujson.decode`.
+   */
+  private class UjsonLoadsCall extends Decoding::Range, DataFlow::CallCfgNode {
+    UjsonLoadsCall() { this = API::moduleImport("ujson").getMember(["loads", "decode"]).getACall() }
+
+    // Note: Most other JSON libraries allow the keyword argument `s`, but as of version
+    // 4.0.2 `ujson` uses `obj` instead.
+    override DataFlow::Node getAnInput() { result in [this.getArg(0), this.getArgByName("obj")] }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+
+    override predicate mayExecuteInput() { none() }
+  }
+
+  /**
+   * A call to `ujson.load`.
+   */
+  private class UjsonLoadCall extends Decoding::Range, DataFlow::CallCfgNode {
+    UjsonLoadCall() { this = API::moduleImport("ujson").getMember("load").getACall() }
+
+    override DataFlow::Node getAnInput() { result = this.getArg(0) }
+
+    override DataFlow::Node getOutput() { result = this }
+
+    override string getFormat() { result = "JSON" }
+
+    override predicate mayExecuteInput() { none() }
+  }
+}

python/ql/test/experimental/dataflow/tainttracking/defaultAdditionalTaintStep/test_json.py

@@ -11,54 +11,43 @@
 # Actual tests
 
 from io import StringIO
-
-# Workaround for Python3 not having unicode
-import sys
-if sys.version_info[0] == 3:
-    unicode = str
+import json
 
 def test():
     print("\n# test")
     ts = TAINTED_STRING
-    import json
+
+    encoded = json.dumps(ts)
 
     ensure_tainted(
+        encoded, # $ tainted
         json.dumps(ts), # $ tainted
-        json.loads(json.dumps(ts)), # $ tainted
+        json.dumps(obj=ts), # $ tainted
+        json.loads(encoded), # $ tainted
+        json.loads(s=encoded), # $ tainted
     )
 
-    # For Python2, need to convert to unicode for StringIO to work
-    tainted_filelike = StringIO(unicode(json.dumps(ts)))
+    # load/dump with file-like
+    tainted_filelike = StringIO()
+    json.dump(ts, tainted_filelike)
 
+    tainted_filelike.seek(0)
     ensure_tainted(
-        tainted_filelike, # $ MISSING: tainted
-        json.load(tainted_filelike), # $ MISSING: tainted
+        tainted_filelike, # $ tainted
+        json.load(tainted_filelike), # $ tainted
     )
 
-def non_syntacical():
-    print("\n# non_syntacical")
-    ts = TAINTED_STRING
-
-    # a less syntactical approach
-    from json import load, loads, dumps
-
-    dumps_alias = dumps
+    # load/dump with file-like using keyword-args
+    tainted_filelike = StringIO()
+    json.dump(obj=ts, fp=tainted_filelike)
 
+    tainted_filelike.seek(0)
     ensure_tainted(
-        dumps(ts), # $ tainted
-        dumps_alias(ts), # $ tainted
-        loads(dumps(ts)), # $ tainted
+        tainted_filelike, # $ tainted
+        json.load(fp=tainted_filelike), # $ tainted
     )
 
-    # For Python2, need to convert to unicode for StringIO to work
-    tainted_filelike = StringIO(unicode(dumps(ts)))
-
-    ensure_tainted(
-        tainted_filelike, # $ MISSING: tainted
-        load(tainted_filelike), # $ MISSING: tainted
-    )
 
 # Make tests runable
 
 test()
-non_syntacical()