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codeql/python/ql/lib/semmle/python/Concepts.qll
2024-09-26 11:44:24 +02:00

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/**
* Provides abstract classes representing generic concepts such as file system
* access or system command execution, for which individual framework libraries
* provide concrete subclasses.
*/
private import python
private import semmle.python.dataflow.new.DataFlow
private import semmle.python.dataflow.new.RemoteFlowSources
private import semmle.python.dataflow.new.TaintTracking
private import semmle.python.Frameworks
private import semmle.python.security.internal.EncryptionKeySizes
private import codeql.threatmodels.ThreatModels
/**
* A data flow source, for a specific threat-model.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `ThreatModelSource::Range` instead.
*/
class ThreatModelSource extends DataFlow::Node instanceof ThreatModelSource::Range {
/**
* Gets a string that represents the source kind with respect to threat modeling.
*
* See
* - https://github.com/github/codeql/blob/main/docs/codeql/reusables/threat-model-description.rst
* - https://github.com/github/codeql/blob/main/shared/threat-models/ext/threat-model-grouping.model.yml
*/
string getThreatModel() { result = super.getThreatModel() }
/** Gets a string that describes the type of this threat-model source. */
string getSourceType() { result = super.getSourceType() }
}
/** Provides a class for modeling new sources for specific threat-models. */
module ThreatModelSource {
/**
* A data flow source, for a specific threat-model.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `ThreatModelSource` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets a string that represents the source kind with respect to threat modeling.
*
* See
* - https://github.com/github/codeql/blob/main/docs/codeql/reusables/threat-model-description.rst
* - https://github.com/github/codeql/blob/main/shared/threat-models/ext/threat-model-grouping.model.yml
*/
abstract string getThreatModel();
/** Gets a string that describes the type of this threat-model source. */
abstract string getSourceType();
}
}
/**
* A data flow source that is enabled in the current threat model configuration.
*/
class ActiveThreatModelSource extends ThreatModelSource {
ActiveThreatModelSource() {
exists(string kind |
currentThreatModel(kind) and
this.getThreatModel() = kind
)
}
}
/**
* A data-flow node that executes an operating system command,
* for instance by spawning a new process.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `SystemCommandExecution::Range` instead.
*/
class SystemCommandExecution extends DataFlow::Node instanceof SystemCommandExecution::Range {
/** Holds if a shell interprets `arg`. */
predicate isShellInterpreted(DataFlow::Node arg) { super.isShellInterpreted(arg) }
/** Gets the argument that specifies the command to be executed. */
DataFlow::Node getCommand() { result = super.getCommand() }
}
/** Provides a class for modeling new system-command execution APIs. */
module SystemCommandExecution {
/**
* A data-flow node that executes an operating system command,
* for instance by spawning a new process.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `SystemCommandExecution` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the command to be executed. */
abstract DataFlow::Node getCommand();
/** Holds if a shell interprets `arg`. */
predicate isShellInterpreted(DataFlow::Node arg) { none() }
}
}
/**
* A data flow node that performs a file system access, including reading and writing data,
* creating and deleting files and folders, checking and updating permissions, and so on.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `FileSystemAccess::Range` instead.
*/
class FileSystemAccess extends DataFlow::Node instanceof FileSystemAccess::Range {
/** Gets an argument to this file system access that is interpreted as a path. */
DataFlow::Node getAPathArgument() { result = super.getAPathArgument() }
}
/** Provides a class for modeling new file system access APIs. */
module FileSystemAccess {
/**
* A data-flow node that performs a file system access, including reading and writing data,
* creating and deleting files and folders, checking and updating permissions, and so on.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `FileSystemAccess` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets an argument to this file system access that is interpreted as a path. */
abstract DataFlow::Node getAPathArgument();
}
}
/**
* A data flow node that writes data to the file system access.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `FileSystemWriteAccess::Range` instead.
*/
class FileSystemWriteAccess extends FileSystemAccess instanceof FileSystemWriteAccess::Range {
/**
* Gets a node that represents data to be written to the file system (possibly with
* some transformation happening before it is written, like JSON encoding).
*/
DataFlow::Node getADataNode() { result = super.getADataNode() }
}
/** Provides a class for modeling new file system writes. */
module FileSystemWriteAccess {
/**
* A data flow node that writes data to the file system access.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `FileSystemWriteAccess` instead.
*/
abstract class Range extends FileSystemAccess::Range {
/**
* Gets a node that represents data to be written to the file system (possibly with
* some transformation happening before it is written, like JSON encoding).
*/
abstract DataFlow::Node getADataNode();
}
}
/** Provides classes for modeling path-related APIs. */
module Path {
/**
* A data-flow node that performs path normalization. This is often needed in order
* to safely access paths.
*/
class PathNormalization extends DataFlow::Node instanceof PathNormalization::Range {
/** Gets an argument to this path normalization that is interpreted as a path. */
DataFlow::Node getPathArg() { result = super.getPathArg() }
}
/** Provides a class for modeling new path normalization APIs. */
module PathNormalization {
/**
* A data-flow node that performs path normalization. This is often needed in order
* to safely access paths.
*/
abstract class Range extends DataFlow::Node {
/** Gets an argument to this path normalization that is interpreted as a path. */
abstract DataFlow::Node getPathArg();
}
}
/** A data-flow node that checks that a path is safe to access. */
class SafeAccessCheck extends DataFlow::ExprNode {
SafeAccessCheck() { this = DataFlow::BarrierGuard<safeAccessCheck/3>::getABarrierNode() }
}
private predicate safeAccessCheck(DataFlow::GuardNode g, ControlFlowNode node, boolean branch) {
g.(SafeAccessCheck::Range).checks(node, branch)
}
/** Provides a class for modeling new path safety checks. */
module SafeAccessCheck {
/** A data-flow node that checks that a path is safe to access. */
abstract class Range extends DataFlow::GuardNode {
/** Holds if this guard validates `node` upon evaluating to `branch`. */
abstract predicate checks(ControlFlowNode node, boolean branch);
}
}
}
/**
* A data-flow node that decodes data from a binary or textual format. This
* is intended to include deserialization, unmarshalling, decoding, unpickling,
* decompressing, decrypting, parsing etc.
*
* A decoding (automatically) preserves taint from input to output. However, it can
* also be a problem in itself, for example if it allows code execution or could result
* in denial-of-service.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `Decoding::Range` instead.
*/
class Decoding extends DataFlow::Node instanceof Decoding::Range {
/** Holds if this call may execute code embedded in its input. */
predicate mayExecuteInput() { super.mayExecuteInput() }
/** Gets an input that is decoded by this function. */
DataFlow::Node getAnInput() { result = super.getAnInput() }
/** Gets the output that contains the decoded data produced by this function. */
DataFlow::Node getOutput() { result = super.getOutput() }
/** Gets an identifier for the format this function decodes from, such as "JSON". */
string getFormat() { result = super.getFormat() }
}
/** Provides a class for modeling new decoding mechanisms. */
module Decoding {
/**
* A data-flow node that decodes data from a binary or textual format. This
* is intended to include deserialization, unmarshalling, decoding, unpickling,
* decompressing, decrypting, parsing etc.
*
* A decoding (automatically) preserves taint from input to output. However, it can
* also be a problem in itself, for example if it allows code execution or could result
* in denial-of-service.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `Decoding` instead.
*/
abstract class Range extends DataFlow::Node {
/** Holds if this call may execute code embedded in its input. */
abstract predicate mayExecuteInput();
/** Gets an input that is decoded by this function. */
abstract DataFlow::Node getAnInput();
/** Gets the output that contains the decoded data produced by this function. */
abstract DataFlow::Node getOutput();
/** Gets an identifier for the format this function decodes from, such as "JSON". */
abstract string getFormat();
}
}
private class DecodingAdditionalTaintStep extends TaintTracking::AdditionalTaintStep {
override predicate step(DataFlow::Node nodeFrom, DataFlow::Node nodeTo, string model) {
exists(Decoding decoding |
nodeFrom = decoding.getAnInput() and
nodeTo = decoding.getOutput() and
model = "Decoding-" + decoding.getFormat()
)
}
}
/**
* A data-flow node that encodes data to a binary or textual format. This
* is intended to include serialization, marshalling, encoding, pickling,
* compressing, encrypting, etc.
*
* An encoding (automatically) preserves taint from input to output.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `Encoding::Range` instead.
*/
class Encoding extends DataFlow::Node instanceof Encoding::Range {
/** Gets an input that is encoded by this function. */
DataFlow::Node getAnInput() { result = super.getAnInput() }
/** Gets the output that contains the encoded data produced by this function. */
DataFlow::Node getOutput() { result = super.getOutput() }
/** Gets an identifier for the format this function decodes from, such as "JSON". */
string getFormat() { result = super.getFormat() }
}
/** Provides a class for modeling new encoding mechanisms. */
module Encoding {
/**
* A data-flow node that encodes data to a binary or textual format. This
* is intended to include serialization, marshalling, encoding, pickling,
* compressing, encrypting, etc.
*
* An encoding (automatically) preserves taint from input to output.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `Encoding` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets an input that is encoded by this function. */
abstract DataFlow::Node getAnInput();
/** Gets the output that contains the encoded data produced by this function. */
abstract DataFlow::Node getOutput();
/** Gets an identifier for the format this function decodes from, such as "JSON". */
abstract string getFormat();
}
}
private class EncodingAdditionalTaintStep extends TaintTracking::AdditionalTaintStep {
override predicate step(DataFlow::Node nodeFrom, DataFlow::Node nodeTo) {
exists(Encoding encoding |
nodeFrom = encoding.getAnInput() and
nodeTo = encoding.getOutput()
)
}
}
/**
* A data-flow node that logs data.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `Logging::Range` instead.
*/
class Logging extends DataFlow::Node instanceof Logging::Range {
/** Gets an input that is logged. */
DataFlow::Node getAnInput() { result = super.getAnInput() }
}
/** Provides a class for modeling new logging mechanisms. */
module Logging {
/**
* A data-flow node that logs data.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `Logging` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets an input that is logged. */
abstract DataFlow::Node getAnInput();
}
}
/**
* A data-flow node that dynamically executes Python code.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `CodeExecution::Range` instead.
*/
class CodeExecution extends DataFlow::Node instanceof CodeExecution::Range {
/** Gets the argument that specifies the code to be executed. */
DataFlow::Node getCode() { result = super.getCode() }
}
/** Provides a class for modeling new dynamic code execution APIs. */
module CodeExecution {
/**
* A data-flow node that dynamically executes Python code.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `CodeExecution` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the code to be executed. */
abstract DataFlow::Node getCode();
}
}
/**
* A data-flow node that constructs an SQL statement.
*
* Often, it is worthy of an alert if an SQL statement is constructed such that
* executing it would be a security risk.
*
* If it is important that the SQL statement is indeed executed, then use `SqlExecution`.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `SqlConstruction::Range` instead.
*/
class SqlConstruction extends DataFlow::Node instanceof SqlConstruction::Range {
/** Gets the argument that specifies the SQL statements to be constructed. */
DataFlow::Node getSql() { result = super.getSql() }
}
/** Provides a class for modeling new SQL execution APIs. */
module SqlConstruction {
/**
* A data-flow node that constructs an SQL statement.
*
* Often, it is worthy of an alert if an SQL statement is constructed such that
* executing it would be a security risk.
*
* If it is important that the SQL statement is indeed executed, then use `SqlExecution`.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `SqlConstruction` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the SQL statements to be constructed. */
abstract DataFlow::Node getSql();
}
}
/**
* A data-flow node that executes SQL statements.
*
* If the context of interest is such that merely constructing an SQL statement
* would be valuable to report, then consider using `SqlConstruction`.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `SqlExecution::Range` instead.
*/
class SqlExecution extends DataFlow::Node instanceof SqlExecution::Range {
/** Gets the argument that specifies the SQL statements to be executed. */
DataFlow::Node getSql() { result = super.getSql() }
}
/** Provides a class for modeling new SQL execution APIs. */
module SqlExecution {
/**
* A data-flow node that executes SQL statements.
*
* If the context of interest is such that merely constructing an SQL statement
* would be valuable to report, then consider using `SqlConstruction`.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `SqlExecution` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the SQL statements to be executed. */
abstract DataFlow::Node getSql();
}
}
/** Provides a class for modeling NoSQL execution APIs. */
module NoSqlExecution {
/**
* A data-flow node that executes NoSQL queries.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `NoSqlExecution` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the NoSQL query to be executed. */
abstract DataFlow::Node getQuery();
/** Holds if this query will unpack/interpret a dictionary */
abstract predicate interpretsDict();
/** Holds if this query can be dangerous when run on a user-controlled string */
abstract predicate vulnerableToStrings();
}
}
/**
* A data-flow node that executes NoSQL queries.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `NoSqlExecution::Range` instead.
*/
class NoSqlExecution extends DataFlow::Node instanceof NoSqlExecution::Range {
/** Gets the argument that specifies the NoSQL query to be executed. */
DataFlow::Node getQuery() { result = super.getQuery() }
/** Holds if this query will unpack/interpret a dictionary */
predicate interpretsDict() { super.interpretsDict() }
/** Holds if this query can be dangerous when run on a user-controlled string */
predicate vulnerableToStrings() { super.vulnerableToStrings() }
}
/** Provides classes for modeling NoSql sanitization-related APIs. */
module NoSqlSanitizer {
/**
* A data-flow node that collects functions sanitizing NoSQL queries.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `NoSQLSanitizer` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the NoSql query to be sanitized. */
abstract DataFlow::Node getAnInput();
}
}
/**
* A data-flow node that collects functions sanitizing NoSQL queries.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `NoSQLSanitizer::Range` instead.
*/
class NoSqlSanitizer extends DataFlow::Node instanceof NoSqlSanitizer::Range {
/** Gets the argument that specifies the NoSql query to be sanitized. */
DataFlow::Node getAnInput() { result = super.getAnInput() }
}
/**
* A data-flow node that executes a regular expression.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `RegexExecution::Range` instead.
*/
class RegexExecution extends DataFlow::Node instanceof RegexExecution::Range {
/** Gets the data flow node for the regex being executed by this node. */
DataFlow::Node getRegex() { result = super.getRegex() }
/** Gets a dataflow node for the string to be searched or matched against. */
DataFlow::Node getString() { result = super.getString() }
/**
* Gets the name of this regex execution, typically the name of an executing method.
* This is used for nice alert messages and should include the module if possible.
*/
string getName() { result = super.getName() }
}
/** Provides classes for modeling new regular-expression execution APIs. */
module RegexExecution {
/**
* A data-flow node that executes a regular expression.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `RegexExecution` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the data flow node for the regex being executed by this node. */
abstract DataFlow::Node getRegex();
/** Gets a dataflow node for the string to be searched or matched against. */
abstract DataFlow::Node getString();
/**
* Gets the name of this regex execution, typically the name of an executing method.
* This is used for nice alert messages and should include the module if possible.
*/
abstract string getName();
}
}
/**
* A node where a string is interpreted as a regular expression,
* for instance an argument to `re.compile`.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `RegExpInterpretation::Range` instead.
*/
class RegExpInterpretation extends DataFlow::Node instanceof RegExpInterpretation::Range { }
/** Provides a class for modeling regular expression interpretations. */
module RegExpInterpretation {
/**
* A node where a string is interpreted as a regular expression,
* for instance an argument to `re.compile`.
*/
abstract class Range extends DataFlow::Node { }
}
/** Provides classes for modeling XML-related APIs. */
module XML {
/**
* A data-flow node that constructs an XPath expression.
*
* Often, it is worthy of an alert if an XPath expression is constructed such that
* executing it would be a security risk.
*
* If it is important that the XPath expression is indeed executed, then use `XPathExecution`.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `XPathConstruction::Range` instead.
*/
class XPathConstruction extends DataFlow::Node instanceof XPathConstruction::Range {
/** Gets the argument that specifies the XPath expressions to be constructed. */
DataFlow::Node getXPath() { result = super.getXPath() }
/**
* Gets the name of this XPath expression construction, typically the name of an executing method.
* This is used for nice alert messages and should include the module if possible.
*/
string getName() { result = super.getName() }
}
/** Provides a class for modeling new XPath construction APIs. */
module XPathConstruction {
/**
* A data-flow node that constructs an XPath expression.
*
* Often, it is worthy of an alert if an XPath expression is constructed such that
* executing it would be a security risk.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `XPathConstruction` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument that specifies the XPath expressions to be constructed. */
abstract DataFlow::Node getXPath();
/**
* Gets the name of this XPath expression construction, typically the name of an executing method.
* This is used for nice alert messages and should include the module if possible.
*/
abstract string getName();
}
}
/**
* A data-flow node that executes a xpath expression.
*
* If the context of interest is such that merely constructing an XPath expression
* would be valuable to report, then consider using `XPathConstruction`.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `XPathExecution::Range` instead.
*/
class XPathExecution extends DataFlow::Node instanceof XPathExecution::Range {
/** Gets the data flow node for the XPath expression being executed by this node. */
DataFlow::Node getXPath() { result = super.getXPath() }
/**
* Gets the name of this XPath expression execution, typically the name of an executing method.
* This is used for nice alert messages and should include the module if possible.
*/
string getName() { result = super.getName() }
}
/** Provides classes for modeling new regular-expression execution APIs. */
module XPathExecution {
/**
* A data-flow node that executes a XPath expression.
*
* If the context of interest is such that merely constructing an XPath expression
* would be valuable to report, then consider using `XPathConstruction`.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `XPathExecution` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the data flow node for the XPath expression being executed by this node. */
abstract DataFlow::Node getXPath();
/**
* Gets the name of this xpath expression execution, typically the name of an executing method.
* This is used for nice alert messages and should include the module if possible.
*/
abstract string getName();
}
}
/**
* A kind of XML vulnerability.
*
* See overview of kinds at https://pypi.org/project/defusedxml/#python-xml-libraries
*
* See PoC at `python/PoCs/XmlParsing/PoC.py` for some tests of vulnerable XML parsing.
*/
class XmlParsingVulnerabilityKind extends string {
XmlParsingVulnerabilityKind() { this in ["XML bomb", "XXE", "DTD retrieval"] }
/**
* Holds for XML bomb vulnerability kind, such as 'Billion Laughs' and 'Quadratic
* Blowup'.
*
* While a parser could technically be vulnerable to one and not the other, from our
* point of view the interesting part is that it IS vulnerable to these types of
* attacks, and not so much which one specifically works. In practice I haven't seen
* a parser that is vulnerable to one and not the other.
*/
predicate isXmlBomb() { this = "XML bomb" }
/** Holds for XXE vulnerability kind. */
predicate isXxe() { this = "XXE" }
/** Holds for DTD retrieval vulnerability kind. */
predicate isDtdRetrieval() { this = "DTD retrieval" }
}
/**
* A data-flow node that parses XML.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `XmlParsing` instead.
*/
class XmlParsing extends Decoding instanceof XmlParsing::Range {
/**
* Holds if this XML parsing is vulnerable to `kind`.
*/
predicate vulnerableTo(XmlParsingVulnerabilityKind kind) { super.vulnerableTo(kind) }
}
/** Provides classes for modeling XML parsing APIs. */
module XmlParsing {
/**
* A data-flow node that parses XML.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `XmlParsing` instead.
*/
abstract class Range extends Decoding::Range {
/**
* Holds if this XML parsing is vulnerable to `kind`.
*/
abstract predicate vulnerableTo(XmlParsingVulnerabilityKind kind);
override string getFormat() { result = "XML" }
}
}
}
/** Provides classes for modeling LDAP-related APIs. */
module Ldap {
/**
* A data-flow node that executes an LDAP query.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `LDAPQuery::Range` instead.
*/
class LdapExecution extends DataFlow::Node instanceof LdapExecution::Range {
/** Gets the argument containing the filter string. */
DataFlow::Node getFilter() { result = super.getFilter() }
/** Gets the argument containing the base DN. */
DataFlow::Node getBaseDn() { result = super.getBaseDn() }
}
/** Provides classes for modeling new LDAP query execution-related APIs. */
module LdapExecution {
/**
* A data-flow node that executes an LDAP query.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `LDAPQuery` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument containing the filter string. */
abstract DataFlow::Node getFilter();
/** Gets the argument containing the base DN. */
abstract DataFlow::Node getBaseDn();
}
}
}
/**
* A data-flow node that escapes meta-characters, which could be used to prevent
* injection attacks.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `Escaping::Range` instead.
*/
class Escaping extends DataFlow::Node instanceof Escaping::Range {
Escaping() {
// escapes that don't have _both_ input/output defined are not valid
exists(super.getAnInput()) and
exists(super.getOutput())
}
/** Gets an input that will be escaped. */
DataFlow::Node getAnInput() { result = super.getAnInput() }
/** Gets the output that contains the escaped data. */
DataFlow::Node getOutput() { result = super.getOutput() }
/**
* Gets the context that this function escapes for, such as `html`, or `url`.
*/
string getKind() { result = super.getKind() }
}
/** Provides a class for modeling new escaping APIs. */
module Escaping {
/**
* A data-flow node that escapes meta-characters, which could be used to prevent
* injection attacks.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `Escaping` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets an input that will be escaped. */
abstract DataFlow::Node getAnInput();
/** Gets the output that contains the escaped data. */
abstract DataFlow::Node getOutput();
/**
* Gets the context that this function escapes for.
*
* While kinds are represented as strings, this should not be relied upon. Use the
* predicates in the `Escaping` module, such as `getHtmlKind`.
*/
abstract string getKind();
}
/** Gets the escape-kind for escaping a string so it can safely be included in HTML. */
string getHtmlKind() { result = "html" }
/** Gets the escape-kind for escaping a string so it can safely be included in XML. */
string getXmlKind() { result = "xml" }
/** Gets the escape-kind for escaping a string so it can safely be included in a regular expression. */
string getRegexKind() { result = "regex" }
/**
* Gets the escape-kind for escaping a string so it can safely be used as a
* distinguished name (DN) in an LDAP search.
*/
string getLdapDnKind() { result = "ldap_dn" }
/**
* Gets the escape-kind for escaping a string so it can safely be used as a
* filter in an LDAP search.
*/
string getLdapFilterKind() { result = "ldap_filter" }
// TODO: If adding an XML kind, update the modeling of the `MarkupSafe` PyPI package.
//
// Technically it claims to escape for both HTML and XML, but for now we don't have
// anything that relies on XML escaping, so I'm going to defer deciding whether they
// should be the same kind, or whether they deserve to be treated differently.
}
/**
* An escape of a string so it can be safely included in
* the body of an HTML element, for example, replacing `{}` in
* `<p>{}</p>`.
*/
class HtmlEscaping extends Escaping {
HtmlEscaping() { super.getKind() = Escaping::getHtmlKind() }
}
/**
* An escape of a string so it can be safely included in
* the body of an XML element, for example, replacing `&` and `<>` in
* `<foo>&xxe;<foo>`.
*/
class XmlEscaping extends Escaping {
XmlEscaping() { super.getKind() = Escaping::getXmlKind() }
}
/**
* An escape of a string so it can be safely included in
* the body of a regex.
*/
class RegexEscaping extends Escaping {
RegexEscaping() { super.getKind() = Escaping::getRegexKind() }
}
/**
* An escape of a string so it can be safely used as a distinguished name (DN)
* in an LDAP search.
*/
class LdapDnEscaping extends Escaping {
LdapDnEscaping() { super.getKind() = Escaping::getLdapDnKind() }
}
/**
* An escape of a string so it can be safely used as a filter in an LDAP search.
*/
class LdapFilterEscaping extends Escaping {
LdapFilterEscaping() { super.getKind() = Escaping::getLdapFilterKind() }
}
/** Provides classes for modeling HTTP-related APIs. */
module Http {
/** Gets an HTTP verb, in upper case */
string httpVerb() { result in ["GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS", "HEAD"] }
/** Gets an HTTP verb, in lower case */
string httpVerbLower() { result = httpVerb().toLowerCase() }
/** Provides classes for modeling HTTP servers. */
module Server {
/**
* A data-flow node that sets up a route on a server.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `RouteSetup::Range` instead.
*/
class RouteSetup extends DataFlow::Node instanceof RouteSetup::Range {
/** Gets the URL pattern for this route, if it can be statically determined. */
string getUrlPattern() { result = super.getUrlPattern() }
/**
* Gets a function that will handle incoming requests for this route, if any.
*
* NOTE: This will be modified in the near future to have a `RequestHandler` result, instead of a `Function`.
*/
Function getARequestHandler() { result = super.getARequestHandler() }
/**
* Gets a parameter that will receive parts of the url when handling incoming
* requests for this route, if any. These automatically become a `RemoteFlowSource`.
*/
Parameter getARoutedParameter() { result = super.getARoutedParameter() }
/** Gets a string that identifies the framework used for this route setup. */
string getFramework() { result = super.getFramework() }
}
/** Provides a class for modeling new HTTP routing APIs. */
module RouteSetup {
/**
* A data-flow node that sets up a route on a server.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `RouteSetup` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the argument used to set the URL pattern. */
abstract DataFlow::Node getUrlPatternArg();
/** Gets the URL pattern for this route, if it can be statically determined. */
string getUrlPattern() {
exists(StringLiteral str |
this.getUrlPatternArg().getALocalSource() = DataFlow::exprNode(str) and
result = str.getText()
)
}
/**
* Gets a function that will handle incoming requests for this route, if any.
*
* NOTE: This will be modified in the near future to have a `RequestHandler` result, instead of a `Function`.
*/
abstract Function getARequestHandler();
/**
* Gets a parameter that will receive parts of the url when handling incoming
* requests for this route, if any. These automatically become a `RemoteFlowSource`.
*/
abstract Parameter getARoutedParameter();
/** Gets a string that identifies the framework used for this route setup. */
abstract string getFramework();
}
}
/**
* A function that will handle incoming HTTP requests.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `RequestHandler::Range` instead.
*/
class RequestHandler extends Function instanceof RequestHandler::Range {
/**
* Gets a parameter that could receive parts of the url when handling incoming
* requests, if any. These automatically become a `RemoteFlowSource`.
*/
Parameter getARoutedParameter() { result = super.getARoutedParameter() }
/** Gets a string that identifies the framework used for this route setup. */
string getFramework() { result = super.getFramework() }
}
/** Provides a class for modeling new HTTP request handlers. */
module RequestHandler {
/**
* A function that will handle incoming HTTP requests.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `RequestHandler` instead.
*
* Only extend this class if you can't provide a `RouteSetup`, since we handle that case automatically.
*/
abstract class Range extends Function {
/**
* Gets a parameter that could receive parts of the url when handling incoming
* requests, if any. These automatically become a `RemoteFlowSource`.
*/
abstract Parameter getARoutedParameter();
/** Gets a string that identifies the framework used for this request handler. */
abstract string getFramework();
}
}
private class RequestHandlerFromRouteSetup extends RequestHandler::Range {
RouteSetup rs;
RequestHandlerFromRouteSetup() { this = rs.getARequestHandler() }
override Parameter getARoutedParameter() {
result = rs.getARoutedParameter() and
result in [
this.getArg(_), this.getArgByName(_), this.getVararg().(Parameter),
this.getKwarg().(Parameter)
]
}
override string getFramework() { result = rs.getFramework() }
}
/** A parameter that will receive parts of the url when handling an incoming request. */
private class RoutedParameter extends RemoteFlowSource::Range, DataFlow::ParameterNode {
RequestHandler handler;
RoutedParameter() { this.getParameter() = handler.getARoutedParameter() }
override string getSourceType() { result = handler.getFramework() + " RoutedParameter" }
}
/**
* A data-flow node that creates a HTTP response on a server.
*
* Note: we don't require that this response must be sent to a client (a kind of
* "if a tree falls in a forest and nobody hears it" situation).
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `HttpResponse::Range` instead.
*/
class HttpResponse extends DataFlow::Node instanceof HttpResponse::Range {
/** Gets the data-flow node that specifies the body of this HTTP response. */
DataFlow::Node getBody() { result = super.getBody() }
/** Gets the mimetype of this HTTP response, if it can be statically determined. */
string getMimetype() { result = super.getMimetype() }
}
/** Provides a class for modeling new HTTP response APIs. */
module HttpResponse {
/**
* A data-flow node that creates a HTTP response on a server.
*
* Note: we don't require that this response must be sent to a client (a kind of
* "if a tree falls in a forest and nobody hears it" situation).
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `HttpResponse` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the data-flow node that specifies the body of this HTTP response. */
abstract DataFlow::Node getBody();
/** Gets the data-flow node that specifies the content-type/mimetype of this HTTP response, if any. */
abstract DataFlow::Node getMimetypeOrContentTypeArg();
/** Gets the default mimetype that should be used if `getMimetypeOrContentTypeArg` has no results. */
abstract string getMimetypeDefault();
/** Gets the mimetype of this HTTP response, if it can be statically determined. */
string getMimetype() {
exists(StringLiteral str |
this.getMimetypeOrContentTypeArg().getALocalSource() = DataFlow::exprNode(str) and
result = str.getText().splitAt(";", 0)
)
or
not exists(this.getMimetypeOrContentTypeArg()) and
result = this.getMimetypeDefault()
}
}
}
/**
* A data-flow node that creates a HTTP redirect response on a server.
*
* Note: we don't require that this redirect must be sent to a client (a kind of
* "if a tree falls in a forest and nobody hears it" situation).
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `HttpRedirectResponse::Range` instead.
*/
class HttpRedirectResponse extends HttpResponse instanceof HttpRedirectResponse::Range {
/** Gets the data-flow node that specifies the location of this HTTP redirect response. */
DataFlow::Node getRedirectLocation() { result = super.getRedirectLocation() }
}
/** Provides a class for modeling new HTTP redirect response APIs. */
module HttpRedirectResponse {
/**
* A data-flow node that creates a HTTP redirect response on a server.
*
* Note: we don't require that this redirect must be sent to a client (a kind of
* "if a tree falls in a forest and nobody hears it" situation).
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `HttpResponse` instead.
*/
abstract class Range extends Http::Server::HttpResponse::Range {
/** Gets the data-flow node that specifies the location of this HTTP redirect response. */
abstract DataFlow::Node getRedirectLocation();
}
}
/**
* A data-flow node that sets a header in an HTTP response.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `ResponseHeaderWrite::Range` instead.
*/
class ResponseHeaderWrite extends DataFlow::Node instanceof ResponseHeaderWrite::Range {
/**
* Gets the argument containing the header name.
*/
DataFlow::Node getNameArg() { result = super.getNameArg() }
/**
* Gets the argument containing the header value.
*/
DataFlow::Node getValueArg() { result = super.getValueArg() }
/**
* Holds if newlines are accepted in the header name argument.
*/
predicate nameAllowsNewline() { super.nameAllowsNewline() }
/**
* Holds if newlines are accepted in the header value argument.
*/
predicate valueAllowsNewline() { super.valueAllowsNewline() }
}
/** Provides a class for modeling header writes on HTTP responses. */
module ResponseHeaderWrite {
/**
*A data-flow node that sets a header in an HTTP response.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `ResponseHeaderWrite` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets the argument containing the header name.
*/
abstract DataFlow::Node getNameArg();
/**
* Gets the argument containing the header value.
*/
abstract DataFlow::Node getValueArg();
/**
* Holds if newlines are accepted in the header name argument.
*/
abstract predicate nameAllowsNewline();
/**
* Holds if newlines are accepted in the header value argument.
*/
abstract predicate valueAllowsNewline();
}
}
/**
* A data-flow node that sets multiple headers in an HTTP response using a dict or a list of tuples.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `ResponseHeaderBulkWrite::Range` instead.
*/
class ResponseHeaderBulkWrite extends DataFlow::Node instanceof ResponseHeaderBulkWrite::Range {
/**
* Gets the argument containing the headers dictionary.
*/
DataFlow::Node getBulkArg() { result = super.getBulkArg() }
/**
* Holds if newlines are accepted in the header name argument.
*/
predicate nameAllowsNewline() { super.nameAllowsNewline() }
/**
* Holds if newlines are accepted in the header value argument.
*/
predicate valueAllowsNewline() { super.valueAllowsNewline() }
}
/** Provides a class for modeling bulk header writes on HTTP responses. */
module ResponseHeaderBulkWrite {
/**
* A data-flow node that sets multiple headers in an HTTP response using a dict.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `ResponseHeaderBulkWrite` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets the argument containing the headers dictionary.
*/
abstract DataFlow::Node getBulkArg();
/**
* Holds if newlines are accepted in the header name argument.
*/
abstract predicate nameAllowsNewline();
/**
* Holds if newlines are accepted in the header value argument.
*/
abstract predicate valueAllowsNewline();
}
}
/** A key-value pair in a literal for a bulk header update, considered as a single header update. */
private class HeaderBulkWriteDictLiteral extends Http::Server::ResponseHeaderWrite::Range instanceof Http::Server::ResponseHeaderBulkWrite
{
KeyValuePair item;
HeaderBulkWriteDictLiteral() {
exists(Dict dict | DataFlow::localFlow(DataFlow::exprNode(dict), super.getBulkArg()) |
item = dict.getAnItem()
)
}
override DataFlow::Node getNameArg() { result.asExpr() = item.getKey() }
override DataFlow::Node getValueArg() { result.asExpr() = item.getValue() }
override predicate nameAllowsNewline() {
Http::Server::ResponseHeaderBulkWrite.super.nameAllowsNewline()
}
override predicate valueAllowsNewline() {
Http::Server::ResponseHeaderBulkWrite.super.valueAllowsNewline()
}
}
/** A tuple in a list for a bulk header update, considered as a single header update. */
private class HeaderBulkWriteListLiteral extends Http::Server::ResponseHeaderWrite::Range instanceof Http::Server::ResponseHeaderBulkWrite
{
Tuple item;
HeaderBulkWriteListLiteral() {
exists(List list | DataFlow::localFlow(DataFlow::exprNode(list), super.getBulkArg()) |
item = list.getAnElt()
)
}
override DataFlow::Node getNameArg() { result.asExpr() = item.getElt(0) }
override DataFlow::Node getValueArg() { result.asExpr() = item.getElt(1) }
override predicate nameAllowsNewline() {
Http::Server::ResponseHeaderBulkWrite.super.nameAllowsNewline()
}
override predicate valueAllowsNewline() {
Http::Server::ResponseHeaderBulkWrite.super.valueAllowsNewline()
}
}
/**
* A data-flow node that sets a cookie in an HTTP response.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `HTTP::CookieWrite::Range` instead.
*/
class CookieWrite extends DataFlow::Node instanceof CookieWrite::Range {
/**
* Gets the argument, if any, specifying the raw cookie header.
*/
DataFlow::Node getHeaderArg() { result = super.getHeaderArg() }
/**
* Gets the argument, if any, specifying the cookie name.
*/
DataFlow::Node getNameArg() { result = super.getNameArg() }
/**
* Gets the argument, if any, specifying the cookie value.
*/
DataFlow::Node getValueArg() { result = super.getValueArg() }
/**
* Holds if the `Secure` flag of the cookie is known to have a value of `b`.
*/
predicate hasSecureFlag(boolean b) { super.hasSecureFlag(b) }
/**
* Holds if the `HttpOnly` flag of the cookie is known to have a value of `b`.
*/
predicate hasHttpOnlyFlag(boolean b) { super.hasHttpOnlyFlag(b) }
/**
* Holds if the `SameSite` attribute of the cookie is known to have a value of `v`.
*/
predicate hasSameSiteAttribute(CookieWrite::SameSiteValue v) { super.hasSameSiteAttribute(v) }
}
/**
* A dataflow call node to a method that sets a cookie in an http response,
* and has common keyword arguments `secure`, `httponly`, and `samesite` to set the attributes of the cookie.
*
* See https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie
*/
abstract class SetCookieCall extends CookieWrite::Range, DataFlow::CallCfgNode {
override predicate hasSecureFlag(boolean b) {
super.hasSecureFlag(b)
or
exists(DataFlow::Node arg, BooleanLiteral bool | arg = this.getArgByName("secure") |
DataFlow::localFlow(DataFlow::exprNode(bool), arg) and
b = bool.booleanValue()
)
or
not exists(this.getArgByName("secure")) and
not exists(this.getKwargs()) and
b = false
}
override predicate hasHttpOnlyFlag(boolean b) {
super.hasHttpOnlyFlag(b)
or
exists(DataFlow::Node arg, BooleanLiteral bool | arg = this.getArgByName("httponly") |
DataFlow::localFlow(DataFlow::exprNode(bool), arg) and
b = bool.booleanValue()
)
or
not exists(this.getArgByName("httponly")) and
not exists(this.getKwargs()) and
b = false
}
override predicate hasSameSiteAttribute(CookieWrite::SameSiteValue v) {
super.hasSameSiteAttribute(v)
or
exists(DataFlow::Node arg, StringLiteral str | arg = this.getArgByName("samesite") |
DataFlow::localFlow(DataFlow::exprNode(str), arg) and
(
str.getText().toLowerCase() = "strict" and
v instanceof CookieWrite::SameSiteStrict
or
str.getText().toLowerCase() = "lax" and
v instanceof CookieWrite::SameSiteLax
or
str.getText().toLowerCase() = "none" and
v instanceof CookieWrite::SameSiteNone
)
)
or
not exists(this.getArgByName("samesite")) and
not exists(this.getKwargs()) and
v instanceof CookieWrite::SameSiteLax // Lax is the default
}
}
/** Provides a class for modeling new cookie writes on HTTP responses. */
module CookieWrite {
/**
* A data-flow node that sets a cookie in an HTTP response.
*
* Note: we don't require that this redirect must be sent to a client (a kind of
* "if a tree falls in a forest and nobody hears it" situation).
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `HttpResponse` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets the argument, if any, specifying the raw cookie header.
*/
abstract DataFlow::Node getHeaderArg();
/**
* Gets the argument, if any, specifying the cookie name.
*/
abstract DataFlow::Node getNameArg();
/**
* Gets the argument, if any, specifying the cookie value.
*/
abstract DataFlow::Node getValueArg();
/**
* Holds if the `Secure` flag of the cookie is known to have a value of `b`.
*/
predicate hasSecureFlag(boolean b) {
exists(StringLiteral sl |
// `sl` is likely a substring of the header
TaintTracking::localTaint(DataFlow::exprNode(sl), this.getHeaderArg()) and
sl.getText().regexpMatch("(?i).*;\\s*secure(;.*|\\s*)") and
b = true
or
// `sl` is the entire header
DataFlow::localFlow(DataFlow::exprNode(sl), this.getHeaderArg()) and
not sl.getText().regexpMatch("(?i).*;\\s*secure(;.*|\\s*)") and
b = false
)
}
/**
* Holds if the `HttpOnly` flag of the cookie is known to have a value of `b`.
*/
predicate hasHttpOnlyFlag(boolean b) {
exists(StringLiteral sl |
// `sl` is likely a substring of the header
TaintTracking::localTaint(DataFlow::exprNode(sl), this.getHeaderArg()) and
sl.getText().regexpMatch("(?i).*;\\s*httponly(;.*|\\s*)") and
b = true
or
// `sl` is the entire header
DataFlow::localFlow(DataFlow::exprNode(sl), this.getHeaderArg()) and
not sl.getText().regexpMatch("(?i).*;\\s*httponly(;.*|\\s*)") and
b = false
)
}
/**
* Holds if the `SameSite` flag of the cookie is known to have a value of `v`.
*/
predicate hasSameSiteAttribute(SameSiteValue v) {
exists(StringLiteral sl |
// `sl` is likely a substring of the header
TaintTracking::localTaint(DataFlow::exprNode(sl), this.getHeaderArg()) and
(
sl.getText().regexpMatch("(?i).*;\\s*samesite=strict(;.*|\\s*)") and
v instanceof SameSiteStrict
or
sl.getText().regexpMatch("(?i).*;\\s*samesite=lax(;.*|\\s*)") and
v instanceof SameSiteLax
or
sl.getText().regexpMatch("(?i).*;\\s*samesite=none(;.*|\\s*)") and
v instanceof SameSiteNone
)
or
// `sl` is the entire header
DataFlow::localFlow(DataFlow::exprNode(sl), this.getHeaderArg()) and
not sl.getText().regexpMatch("(?i).*;\\s*samesite=(strict|lax|none)(;.*|\\s*)") and
v instanceof SameSiteLax // Lax is the default
)
}
}
private newtype TSameSiteValue =
TSameSiteStrict() or
TSameSiteLax() or
TSameSiteNone()
/** A possible value for the SameSite attribute of a cookie. */
class SameSiteValue extends TSameSiteValue {
/** Gets a string representation of this value. */
string toString() { none() }
}
/** A `Strict` value of the `SameSite` attribute. */
class SameSiteStrict extends SameSiteValue, TSameSiteStrict {
override string toString() { result = "Strict" }
}
/** A `Lax` value of the `SameSite` attribute. */
class SameSiteLax extends SameSiteValue, TSameSiteLax {
override string toString() { result = "Lax" }
}
/** A `None` value of the `SameSite` attribute. */
class SameSiteNone extends SameSiteValue, TSameSiteNone {
override string toString() { result = "None" }
}
}
/** A write to a `Set-Cookie` header that sets a cookie directly. */
private class CookieHeaderWrite extends CookieWrite::Range instanceof Http::Server::ResponseHeaderWrite
{
CookieHeaderWrite() {
exists(StringLiteral str |
str.getText().toLowerCase() = "set-cookie" and
DataFlow::exprNode(str)
.(DataFlow::LocalSourceNode)
.flowsTo(this.(Http::Server::ResponseHeaderWrite).getNameArg())
)
}
override DataFlow::Node getNameArg() { none() }
override DataFlow::Node getHeaderArg() {
result = this.(Http::Server::ResponseHeaderWrite).getValueArg()
}
override DataFlow::Node getValueArg() { none() }
}
/**
* A data-flow node that enables or disables CORS
* in a global manner.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `CorsMiddleware::Range` instead.
*/
class CorsMiddleware extends DataFlow::Node instanceof CorsMiddleware::Range {
/**
* Gets the string corresponding to the middleware
*/
string getMiddlewareName() { result = super.getMiddlewareName() }
/**
* Gets the dataflow node corresponding to the allowed CORS origins
*/
DataFlow::Node getOrigins() { result = super.getOrigins() }
/**
* Gets the boolean value corresponding to if CORS credentials is enabled
* (`true`) or disabled (`false`) by this node.
*/
DataFlow::Node getCredentialsAllowed() { result = super.getCredentialsAllowed() }
}
/** Provides a class for modeling new CORS middleware APIs. */
module CorsMiddleware {
/**
* A data-flow node that enables or disables Cross-site request forgery protection
* in a global manner.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `CorsMiddleware` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets the name corresponding to the middleware
*/
abstract string getMiddlewareName();
/**
* Gets the strings corresponding to the origins allowed by the cors policy
*/
abstract DataFlow::Node getOrigins();
/**
* Gets the boolean value corresponding to if CORS credentials is enabled
* (`true`) or disabled (`false`) by this node.
*/
abstract DataFlow::Node getCredentialsAllowed();
}
}
/**
* A data-flow node that enables or disables Cross-site request forgery protection
* in a global manner.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `CsrfProtectionSetting::Range` instead.
*/
class CsrfProtectionSetting extends DataFlow::Node instanceof CsrfProtectionSetting::Range {
/**
* Gets the boolean value corresponding to if CSRF protection is enabled
* (`true`) or disabled (`false`) by this node.
*/
boolean getVerificationSetting() { result = super.getVerificationSetting() }
}
/** Provides a class for modeling new CSRF protection setting APIs. */
module CsrfProtectionSetting {
/**
* A data-flow node that enables or disables Cross-site request forgery protection
* in a global manner.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `CsrfProtectionSetting` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets the boolean value corresponding to if CSRF protection is enabled
* (`true`) or disabled (`false`) by this node.
*/
abstract boolean getVerificationSetting();
}
}
/**
* A data-flow node that enables or disables Cross-site request forgery protection
* for a specific part of an application.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `CsrfLocalProtectionSetting::Range` instead.
*/
class CsrfLocalProtectionSetting extends DataFlow::Node instanceof CsrfLocalProtectionSetting::Range
{
/**
* Gets a request handler whose CSRF protection is changed.
*/
Function getRequestHandler() { result = super.getRequestHandler() }
/** Holds if CSRF protection is enabled by this setting */
predicate csrfEnabled() { super.csrfEnabled() }
}
/** Provides a class for modeling new CSRF protection setting APIs. */
module CsrfLocalProtectionSetting {
/**
* A data-flow node that enables or disables Cross-site request forgery protection
* for a specific part of an application.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `CsrfLocalProtectionSetting` instead.
*/
abstract class Range extends DataFlow::Node {
/**
* Gets a request handler whose CSRF protection is changed.
*/
abstract Function getRequestHandler();
/** Holds if CSRF protection is enabled by this setting */
abstract predicate csrfEnabled();
}
}
}
import semmle.python.internal.ConceptsShared::Http::Client as Client
// TODO: investigate whether we should treat responses to client requests as
// remote-flow-sources in general.
}
/**
* Provides models for cryptographic things.
*
* Note: The `CryptographicAlgorithm` class currently doesn't take weak keys into
* consideration for the `isWeak` member predicate. So RSA is always considered
* secure, although using a low number of bits will actually make it insecure. We plan
* to improve our libraries in the future to more precisely capture this aspect.
*/
module Cryptography {
/** Provides models for public-key cryptography, also called asymmetric cryptography. */
module PublicKey {
/**
* A data-flow node that generates a new key-pair for use with public-key cryptography.
*
* Extend this class to refine existing API models. If you want to model new APIs,
* extend `KeyGeneration::Range` instead.
*/
class KeyGeneration extends DataFlow::Node instanceof KeyGeneration::Range {
/** Gets the name of the cryptographic algorithm (for example `"RSA"` or `"AES"`). */
string getName() { result = super.getName() }
/** Gets the argument that specifies the size of the key in bits, if available. */
DataFlow::Node getKeySizeArg() { result = super.getKeySizeArg() }
/**
* Gets the size of the key generated (in bits), as well as the `origin` that
* explains how we obtained this specific key size.
*/
int getKeySizeWithOrigin(DataFlow::Node origin) {
result = super.getKeySizeWithOrigin(origin)
}
/** Gets the minimum key size (in bits) for this algorithm to be considered secure. */
int minimumSecureKeySize() { result = super.minimumSecureKeySize() }
}
/** Provides classes for modeling new key-pair generation APIs. */
module KeyGeneration {
/** Gets a back-reference to the keysize argument `arg` that was used to generate a new key-pair. */
private DataFlow::TypeTrackingNode keysizeBacktracker(
DataFlow::TypeBackTracker t, DataFlow::Node arg
) {
t.start() and
arg = any(KeyGeneration::Range r).getKeySizeArg() and
result = arg.getALocalSource()
or
exists(DataFlow::TypeBackTracker t2 | result = keysizeBacktracker(t2, arg).backtrack(t2, t))
}
/** Gets a back-reference to the keysize argument `arg` that was used to generate a new key-pair. */
DataFlow::LocalSourceNode keysizeBacktracker(DataFlow::Node arg) {
result = keysizeBacktracker(DataFlow::TypeBackTracker::end(), arg)
}
/**
* A data-flow node that generates a new key-pair for use with public-key cryptography.
*
* Extend this class to model new APIs. If you want to refine existing API models,
* extend `KeyGeneration` instead.
*/
abstract class Range extends DataFlow::Node {
/** Gets the name of the cryptographic algorithm (for example `"RSA"`). */
abstract string getName();
/** Gets the argument that specifies the size of the key in bits, if available. */
abstract DataFlow::Node getKeySizeArg();
/**
* Gets the size of the key generated (in bits), as well as the `origin` that
* explains how we obtained this specific key size.
*/
int getKeySizeWithOrigin(DataFlow::Node origin) {
origin = keysizeBacktracker(this.getKeySizeArg()) and
result = origin.asExpr().(IntegerLiteral).getValue()
}
/** Gets the minimum key size (in bits) for this algorithm to be considered secure. */
abstract int minimumSecureKeySize();
}
/** A data-flow node that generates a new RSA key-pair. */
abstract class RsaRange extends Range {
final override string getName() { result = "RSA" }
final override int minimumSecureKeySize() { result = minSecureKeySizeRsa() }
}
/** A data-flow node that generates a new DSA key-pair. */
abstract class DsaRange extends Range {
final override string getName() { result = "DSA" }
final override int minimumSecureKeySize() { result = minSecureKeySizeDsa() }
}
/** A data-flow node that generates a new ECC key-pair. */
abstract class EccRange extends Range {
final override string getName() { result = "ECC" }
final override int minimumSecureKeySize() { result = minSecureKeySizeEcc() }
}
}
}
import semmle.python.internal.ConceptsShared::Cryptography
}