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codeql/javascript/ql/lib/semmle/javascript/frameworks/CryptoLibraries.qll
Max Schaefer 08cc8b8e80 Autoformat.
2023-10-26 15:36:06 +01:00

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/**
* Provides classes for modeling cryptographic libraries.
*/
import javascript
import semmle.javascript.Concepts::Cryptography
private import semmle.javascript.security.internal.CryptoAlgorithmNames
/**
* A key used in a cryptographic algorithm.
*/
abstract class CryptographicKey extends DataFlow::ValueNode { }
/**
* The creation of a cryptographic key.
*/
abstract class CryptographicKeyCreation extends DataFlow::Node {
/**
* Gets the algorithm used to create the key.
*/
abstract CryptographicAlgorithm getAlgorithm();
/**
* Gets the size of the key.
*/
abstract int getSize();
/**
* Gets whether the key is symmetric.
*/
abstract predicate isSymmetricKey();
}
/**
* A key used in a cryptographic algorithm, viewed as a `CredentialsNode`.
*/
class CryptographicKeyCredentialsExpr extends CredentialsNode instanceof CryptographicKey {
override string getCredentialsKind() { result = "key" }
}
// Holds if `algorithm` is an `EncryptionAlgorithm` that uses a block cipher
private predicate isBlockEncryptionAlgorithm(CryptographicAlgorithm algorithm) {
algorithm instanceof EncryptionAlgorithm and
not algorithm.(EncryptionAlgorithm).isStreamCipher()
}
/**
* A model of the asmCrypto library.
*/
private module AsmCrypto {
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm; // non-functional
DataFlow::PropRead algorithmSelection;
private string algorithmName;
private string methodName;
Apply() {
/*
* ```
* asmCrypto.SHA256.hex(input)
* ```
* matched as:
* ```
* asmCrypto.<algorithmName>._(<input>)
* ```
*/
exists(DataFlow::SourceNode asmCrypto |
asmCrypto = DataFlow::globalVarRef("asmCrypto") and
algorithm.matchesName(algorithmName) and
algorithmSelection = asmCrypto.getAPropertyRead(algorithmName) and
this = algorithmSelection.getAMemberCall(methodName) and
input = this.getArgument(0)
)
}
override DataFlow::Node getInitialization() { result = algorithmSelection }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
override BlockMode getBlockMode() {
isBlockEncryptionAlgorithm(this.getAlgorithm()) and
result.matchesString(algorithmName)
}
DataFlow::Node getKey() {
methodName = ["encrypt", "decrypt"] and
result = super.getArgument(1)
}
}
private class Key extends CryptographicKey {
Key() { this = any(Apply apply).getKey() }
}
}
/**
* A model of the browserid-crypto library.
*/
private module BrowserIdCrypto {
private class Key extends CryptographicKey {
Key() { this = any(Apply apply).getKey() }
}
private class Apply extends CryptographicOperation::Range instanceof DataFlow::MethodCallNode {
CryptographicAlgorithm algorithm; // non-functional
DataFlow::CallNode keygen;
Apply() {
/*
* ```
* var jwcrypto = require("browserid-crypto");
* jwcrypto.generateKeypair({algorithm: 'DSA'}, function() {
* jwcrypto.sign(input, key);
* });
* ```
* matched as:
* ```
* var jwcrypto = require("browserid-crypto");
* jwcrypto.generateKeypair({algorithm: <algorithmName>}, function() {
* jwcrypto.sign(<input>, <key>);
* });
* ```
*/
exists(
DataFlow::SourceNode mod, DataFlow::Node algorithmNameNode, DataFlow::FunctionNode callback
|
mod = DataFlow::moduleImport("browserid-crypto") and
keygen = mod.getAMemberCall("generateKeypair") and
algorithmNameNode = keygen.getOptionArgument(0, "algorithm") and
algorithm.matchesName(algorithmNameNode.getStringValue()) and
callback = keygen.getCallback(1) and
this = mod.getAMemberCall("sign")
)
}
override DataFlow::Node getInitialization() { result = keygen }
override DataFlow::Node getAnInput() { result = super.getArgument(0) }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// not relevant for browserid-crypto
override BlockMode getBlockMode() { none() }
DataFlow::Node getKey() { result = super.getArgument(1) }
}
}
/**
* A model of the Node.js builtin crypto library.
*/
private module NodeJSCrypto {
private class InstantiatedAlgorithm extends API::CallNode {
private string algorithmName;
InstantiatedAlgorithm() {
/*
* ```
* const crypto = require('crypto');
* const cipher = crypto.createCipher('aes192', 'a password');
* ```
* matched as:
* ```
* const crypto = require('crypto');
* const cipher = crypto.createCipher(<algorithmName>, 'a password');
* ```
* Also matches `createHash`, `createHmac`, `createSign` instead of `createCipher`.
*/
this =
API::moduleImport("crypto")
.getMember("create" + ["Hash", "Hmac", "Sign", "Cipher"])
.getACall() and
algorithmName = this.getArgument(0).getStringValue()
}
CryptographicAlgorithm getAlgorithm() { result.matchesName(algorithmName) }
private BlockMode getExplicitBlockMode() { result.matchesString(algorithmName) }
BlockMode getBlockMode() {
isBlockEncryptionAlgorithm(this.getAlgorithm()) and
(
if exists(this.getExplicitBlockMode())
then result = this.getExplicitBlockMode()
else
// CBC is the default if not explicitly specified
result = "CBC"
)
}
}
private class CreateKey extends CryptographicKeyCreation, DataFlow::CallNode {
boolean symmetric;
CreateKey() {
// crypto.generateKey(type, options, callback)
// crypto.generateKeyPair(type, options, callback)
// crypto.generateKeyPairSync(type, options)
// crypto.generateKeySync(type, options)
exists(string keyType |
keyType = "Key" and symmetric = true
or
keyType = "KeyPair" and symmetric = false
|
this = API::moduleImport("crypto").getMember("generate" + keyType + ["", "Sync"]).getACall()
)
}
override CryptographicAlgorithm getAlgorithm() {
result.matchesName(this.getArgument(0).getStringValue())
}
override int getSize() {
symmetric = true and
result = this.getOptionArgument(1, "length").getIntValue()
or
symmetric = false and
result = this.getOptionArgument(1, "modulusLength").getIntValue()
}
override predicate isSymmetricKey() { symmetric = true }
}
private class CreateDiffieHellmanKey extends CryptographicKeyCreation, DataFlow::CallNode {
// require("crypto").createDiffieHellman(prime_length);
CreateDiffieHellmanKey() {
this = DataFlow::moduleMember("crypto", "createDiffieHellman").getACall()
}
override CryptographicAlgorithm getAlgorithm() { none() }
override int getSize() { result = this.getArgument(0).getIntValue() }
override predicate isSymmetricKey() { none() }
}
private class Apply extends CryptographicOperation::Range instanceof DataFlow::MethodCallNode {
InstantiatedAlgorithm instantiation;
Apply() { this = instantiation.getAMethodCall(any(string m | m = "update" or m = "write")) }
override DataFlow::Node getInitialization() { result = instantiation }
override DataFlow::Node getAnInput() { result = super.getArgument(0) }
override CryptographicAlgorithm getAlgorithm() { result = instantiation.getAlgorithm() }
override BlockMode getBlockMode() { result = instantiation.getBlockMode() }
}
private class Key extends CryptographicKey {
Key() {
this =
any(InstantiatedAlgorithm i)
.getReturn()
.getMember(["setPrivateKey", "sign"])
.getParameter(0)
.asSink()
or
exists(string name, int index |
this = API::moduleImport("crypto").getMember(name).getACall().getArgument(index)
|
index = 0 and
(name = "privateDecrypt" or name = "privateEncrypt")
or
index = 1 and
(name = "createCipheriv" or name = "Decipheriv" or name = "createHmac")
)
}
}
}
/**
* A model of the crypto-js library.
*/
private module CryptoJS {
private class InstantiatedAlgorithm extends DataFlow::CallNode {
private string algorithmName;
InstantiatedAlgorithm() {
/*
* ```
* const crypto = require("crypto-js");
* const cipher = crypto.algo.SHA256.create();
* ```
* matched as:
* ```
* const crypto = require("crypto-js");
* const cipher = crypto.algo.<algorithmName>.create();
* ```
*/
this =
API::moduleImport("crypto-js")
.getMember("algo")
.getMember(algorithmName)
.getMember("create")
.getACall() and
not isStrongPasswordHashingAlgorithm(algorithmName)
}
CryptographicAlgorithm getAlgorithm() { result.matchesName(algorithmName) }
private BlockMode getExplicitBlockMode() { result.matchesString(algorithmName) }
BlockMode getBlockMode() {
isBlockEncryptionAlgorithm(this.getAlgorithm()) and
(
if exists(this.getExplicitBlockMode())
then result = this.getExplicitBlockMode()
else
// CBC is the default if not explicitly specified
result = "CBC"
)
}
}
/**
* Matches `CryptoJS.<algorithmName>` and `require("crypto-js/<algorithmName>")`
*/
private API::Node getAlgorithmNode(CryptographicAlgorithm algorithm) {
exists(string algorithmName | algorithm.matchesName(algorithmName) |
result = API::moduleImport("crypto-js").getMember([algorithmName, "Hmac" + algorithmName])
or
result = API::moduleImport("crypto-js/" + algorithmName)
)
}
private API::CallNode getEncryptionApplication(
API::Node input, API::Node algorithmNode, CryptographicAlgorithm algorithm
) {
/*
* ```
* var CryptoJS = require("crypto-js");
* CryptoJS.AES.encrypt('my message', 'secret key 123');
* ```
* Matched as:
* ```
* var CryptoJS = require("crypto-js");
* CryptoJS.<algorithmName>.encrypt(<input>, 'secret key 123');
* ```
* Also matches where `CryptoJS.<algorithmName>` has been replaced by `require("crypto-js/<algorithmName>")`
*/
algorithmNode = getAlgorithmNode(algorithm) and
result = algorithmNode.getMember("encrypt").getACall() and
input = result.getParameter(0)
}
private API::CallNode getDirectApplication(
API::Node input, API::Node algorithmNode, CryptographicAlgorithm algorithm
) {
/*
* ```
* var CryptoJS = require("crypto-js");
* CryptoJS.SHA1("Message", "Key");
* ```
* Matched as:
* ```
* var CryptoJS = require("crypto-js");
* CryptoJS.<algorithmName>(<input>, "Key");
* ```
* An `Hmac`-prefix of <algorithmName> is ignored.
* Also matches where `CryptoJS.<algorithmName>` has been replaced by `require("crypto-js/<algorithmName>")`
*/
algorithmNode = getAlgorithmNode(algorithm) and
result = algorithmNode.getACall() and
input = result.getParameter(0)
}
private API::CallNode getUpdatedApplication(API::Node input, InstantiatedAlgorithm instantiation) {
/*
* ```
* var CryptoJS = require("crypto-js");
* var hash = CryptoJS.algo.SHA256.create();
* hash.update('message');
* hash.update('password');
* var hashInHex = hash.finalize();
* ```
* Matched as:
* ```
* var CryptoJS = require("crypto-js");
* var hash = CryptoJS.algo.<algorithmName>.create();
* hash.update(<input>);
* hash.update(<input>);
* var hashInHex = hash.finalize();
* ```
* Also matches where `CryptoJS.algo.<algorithmName>` has been
* replaced by `require("crypto-js/<algorithmName>")`
*/
result = instantiation.getAMemberCall("update") and
input = result.getParameter(0)
}
private class Apply extends CryptographicOperation::Range instanceof API::CallNode {
API::Node input;
CryptographicAlgorithm algorithm; // non-functional
DataFlow::Node instantiation;
Apply() {
exists(API::Node algorithmNode |
this = getEncryptionApplication(input, algorithmNode, algorithm)
or
this = getDirectApplication(input, algorithmNode, algorithm)
|
instantiation = algorithmNode.asSource()
)
or
this = getUpdatedApplication(input, instantiation) and
algorithm = instantiation.(InstantiatedAlgorithm).getAlgorithm()
}
override DataFlow::Node getInitialization() { result = instantiation }
override DataFlow::Node getAnInput() { result = input.asSink() }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// e.g. CryptoJS.AES.encrypt("msg", "key", { mode: CryptoJS.mode.<modeString> })
private BlockMode getExplicitBlockMode() {
exists(string modeString |
API::moduleImport("crypto-js").getMember("mode").getMember(modeString).asSource() =
super.getParameter(2).getMember("mode").asSink()
|
result.matchesString(modeString)
)
}
override BlockMode getBlockMode() {
isBlockEncryptionAlgorithm(this.getAlgorithm()) and
(
if exists(this.getExplicitBlockMode())
then result = this.getExplicitBlockMode()
else
// CBC is the default if not explicitly specified
result = "CBC"
)
}
}
private class Key extends CryptographicKey {
Key() {
exists(API::Node e, CryptographicAlgorithm algorithm | e = getAlgorithmNode(algorithm) |
exists(string name |
name = "encrypt" or
name = "decrypt"
|
algorithm instanceof EncryptionAlgorithm and
this = e.getMember(name).getACall().getArgument(1)
)
or
algorithm instanceof HashingAlgorithm and
this = e.getACall().getArgument(1)
)
}
}
private class CreateKey extends CryptographicKeyCreation, DataFlow::CallNode {
string algorithm;
int optionArg;
CreateKey() {
// var key = CryptoJS.PBKDF2(password, salt, { keySize: 8 });
this =
getAlgorithmNode(any(CryptographicAlgorithm algo | algo.getName() = algorithm)).getACall() and
optionArg = 2
or
// var key = CryptoJS.algo.PBKDF2.create({ keySize: 8 });
this =
DataFlow::moduleMember("crypto-js", "algo")
.getAPropertyRead(algorithm)
.getAMethodCall("create") and
optionArg = 0
}
override CryptographicAlgorithm getAlgorithm() { result.matchesName(algorithm) }
override int getSize() {
result = this.getOptionArgument(optionArg, "keySize").getIntValue() * 32 // size is in words
or
result = this.getArgument(optionArg).getIntValue() * 32 // size is in words
}
override predicate isSymmetricKey() { any() }
}
}
/**
* A model of the TweetNaCl library.
*/
private module TweetNaCl {
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm;
Apply() {
/*
* ```
* require("nacl").sign('my message');
* ```
* Matched as:
* ```
* require("nacl").sign(<input>);
* ```
* Also matches the "hash" method name, and the "nacl-fast" module.
*/
exists(string name |
name = "hash" and algorithm.matchesName("SHA512")
or
name = "sign" and algorithm.matchesName("ed25519")
|
this = API::moduleImport(["nacl", "nacl-fast"]).getMember(name).getACall() and
super.getArgument(0) = input
)
}
override DataFlow::Node getInitialization() { result = this }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// No block ciphers implemented
override BlockMode getBlockMode() { none() }
}
}
/**
* A model of the hash.js library.
*/
private module HashJs {
/**
* Matches:
* - `require("hash.js").<algorithmName>`()
* - `require("hash.js/lib/hash/<algorithmName>")`()
* - `require("hash.js/lib/hash/sha/<sha-algorithm-suffix>")`()
*/
private DataFlow::CallNode getAlgorithmNode(CryptographicAlgorithm algorithm) {
exists(string algorithmName | algorithm.matchesName(algorithmName) |
result = API::moduleImport("hash.js").getMember(algorithmName).getACall()
or
result = API::moduleImport("hash.js/lib/hash/" + algorithmName).getACall()
or
exists(string size |
result = API::moduleImport("hash.js/lib/hash/sha/" + size).getACall() and
algorithmName = "SHA" + size
)
)
}
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm; // non-functional
DataFlow::CallNode init;
Apply() {
/*
* ```
* var hash = require("hash.js");
* hash.sha512().update('my message', 'secret key 123');
* ```
* Matched as:
* ```
* var hash = require("hash.js");
* hash.<algorithmName>().update('my message', 'secret key 123');
* ```
* Also matches where `hash.<algorithmName>()` has been replaced by a more specific require a la `require("hash.js/lib/hash/sha/512")`
*/
init = getAlgorithmNode(algorithm) and
this = init.getAMemberCall("update") and
input = super.getArgument(0)
}
override DataFlow::Node getInitialization() { result = init }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// not relevant for hash.js
override BlockMode getBlockMode() { none() }
}
}
/**
* A model of the forge library.
*/
private module Forge {
private API::Node getAnImportNode() { result = API::moduleImport(["forge", "node-forge"]) }
abstract private class Cipher extends DataFlow::CallNode {
abstract CryptographicAlgorithm getAlgorithm();
}
private class KeyCipher extends Cipher {
DataFlow::Node key;
CryptographicAlgorithm algorithm; // non-functional
private string blockModeString;
KeyCipher() {
exists(string algorithmName | algorithm.matchesName(algorithmName) |
exists(string cipherName, string cipherPrefix |
// `require('forge').cipher.createCipher("3DES-CBC").update("secret", "key");`
this =
getAnImportNode()
.getMember("cipher")
.getMember(["createCipher", "createDecipher"])
.getACall() and
this.getArgument(0).mayHaveStringValue(cipherName) and
cipherName = cipherPrefix + "-" + blockModeString and
blockModeString = ["CBC", "CFB", "CTR", "ECB", "GCM", "OFB"] and
algorithmName = cipherPrefix and
key = this.getArgument(1)
)
or
// `require("forge").rc2.createEncryptionCipher("key").update("secret");`
this =
getAnImportNode()
.getMember(algorithmName)
.getMember(["createEncryptionCipher", "createDecryptionCipher"])
.getACall() and
key = this.getArgument(0) and
blockModeString = algorithmName
)
}
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
DataFlow::Node getKey() { result = key }
BlockMode getBlockMode() {
isBlockEncryptionAlgorithm(this.getAlgorithm()) and
result.matchesString(blockModeString)
}
}
private class NonKeyCipher extends Cipher {
CryptographicAlgorithm algorithm; // non-functional
NonKeyCipher() {
exists(string algorithmName | algorithm.matchesName(algorithmName) |
// require("forge").md.md5.create().update('The quick brown fox jumps over the lazy dog');
this =
getAnImportNode().getMember("md").getMember(algorithmName).getMember("create").getACall()
or
// require("forge").sha512.sha256.create().update('The quick brown fox jumps over the lazy dog');
this =
getAnImportNode()
.getMember("md")
.getMember(algorithmName)
.getAMember()
.getMember("create")
.getACall()
)
}
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
}
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm; // non-functional
private Cipher cipher;
Apply() {
this = cipher.getAMemberCall("update") and
super.getArgument(0) = input and
algorithm = cipher.getAlgorithm()
}
override DataFlow::Node getInitialization() { result = cipher }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
override BlockMode getBlockMode() { result = cipher.(KeyCipher).getBlockMode() }
}
private class Key extends CryptographicKey {
Key() { this = any(KeyCipher cipher).getKey() }
}
private class CreateKey extends CryptographicKeyCreation, DataFlow::CallNode {
CryptographicAlgorithm algorithm;
CreateKey() {
// var cipher = forge.rc2.createEncryptionCipher(key, 128);
this =
getAnImportNode()
.getMember(any(string s | algorithm.matchesName(s)))
.getMember("createEncryptionCipher")
.getACall()
or
// var key = forge.random.getBytesSync(16);
// var cipher = forge.cipher.createCipher('AES-CBC', key);
this =
getAnImportNode()
.getMember("cipher")
.getMember(["createCipher", "createDecipher"])
.getACall() and
algorithm.matchesName(this.getArgument(0).getStringValue())
}
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
override int getSize() {
result = this.getArgument(1).getIntValue()
or
exists(DataFlow::CallNode call | call.getCalleeName() = ["getBytes", "getBytesSync"] |
this.getArgument(1).getALocalSource() = call and
result = call.getArgument(0).getIntValue() * 8 // bytes to bits
)
}
override predicate isSymmetricKey() { any() }
}
}
/**
* A model of the md5 library.
*/
private module Md5 {
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm;
Apply() {
// `require("md5")("message");`
algorithm.matchesName("MD5") and
this = API::moduleImport("md5").getACall() and
super.getArgument(0) = input
}
override DataFlow::Node getInitialization() { result = this }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// not relevant for md5
override BlockMode getBlockMode() { none() }
}
}
/**
* A model of the bcrypt, bcryptjs, bcrypt-nodejs libraries.
*/
private module Bcrypt {
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm;
API::Node init;
Apply() {
// `require("bcrypt").hash(password);` with minor naming variations
algorithm.matchesName("BCRYPT") and
init = API::moduleImport(["bcrypt", "bcryptjs", "bcrypt-nodejs"]) and
this = init.getMember(["hash", "hashSync"]).getACall() and
super.getArgument(0) = input
}
override DataFlow::Node getInitialization() { result = init.asSource() }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// not relevant for bcrypt
override BlockMode getBlockMode() { none() }
}
}
/**
* A model of the hasha library.
*/
private module Hasha {
private class Apply extends CryptographicOperation::Range instanceof DataFlow::CallNode {
DataFlow::Node input;
CryptographicAlgorithm algorithm;
Apply() {
// `require('hasha')('unicorn', { algorithm: "md5" });`
exists(string algorithmName |
this = API::moduleImport("hasha").getACall() and
super.getArgument(0) = input and
algorithm.matchesName(algorithmName) and
super.getOptionArgument(1, "algorithm").mayHaveStringValue(algorithmName)
)
}
override DataFlow::Node getInitialization() { result = this }
override DataFlow::Node getAnInput() { result = input }
override CryptographicAlgorithm getAlgorithm() { result = algorithm }
// not relevant for hasha
override BlockMode getBlockMode() { none() }
}
}
/**
* Provides classes for working with the `express-jwt` package (https://github.com/auth0/express-jwt);
*/
private module ExpressJwt {
private class Key extends CryptographicKey {
Key() { this = API::moduleImport("express-jwt").getMember("sign").getACall().getArgument(1) }
}
}
/**
* Provides classes for working with the `node-rsa` package (https://www.npmjs.com/package/node-rsa)
*/
private module NodeRsa {
private class CreateKey extends CryptographicKeyCreation, API::InvokeNode {
CreateKey() {
this = API::moduleImport("node-rsa").getAnInstantiation()
or
this = API::moduleImport("node-rsa").getInstance().getMember("generateKeyPair").getACall()
}
override CryptographicAlgorithm getAlgorithm() { result.matchesName("rsa") }
override int getSize() {
result = this.getArgument(0).getIntValue()
or
result = this.getOptionArgument(0, "b").getIntValue()
}
override predicate isSymmetricKey() { none() }
}
}