Crate redos_detector 

Static ReDoS analysis for ECMA-262 regular expressions.

This crate scores how vulnerable a regular expression is to ReDoS (regular-expression denial of service). It does not run the pattern. It enumerates the ways an input prefix could match and counts how many distinct paths can match the same prefix. More ambiguity means more backtracking, so a higher score. A score of 1 means every input matches at most one way. An infinite score means backtracking is unbounded.

Start with is_safe for a check that reads flags from the pattern string, or is_safe_pattern for a raw pattern with explicit options. to_friendly renders a result as text. downgrade_pattern rewrites unsupported patterns into supported ones.

Recoverable input problems return Error: an unsupported flag, a conflicting config, or a pattern that fails to parse. A successful check returns a Report. When the analysis hits a cap the report carries an AnalysisLimit in its error field, which is a different axis from input validation.

use redos_detector::{is_safe, Config};

let result = is_safe("(a+)+$", "", &Config::default()).unwrap();
assert!(!result.is_safe());

Structs

BackReference

A backreference in a trail side.

Config

Options for is_safe and is_safe_pattern.

DowngradedRegexPattern

A downgraded pattern and the offsets of any atomic groups it introduced.

Node

A node in the checked pattern.

NodeLocation

A location in the checked pattern. The first character has offset 0.

QuantifierIteration

A quantifier iteration in a trail side.

Report

The result of a check.

ToFriendlyConfig

Options for to_friendly.

Trail

A trail: a pair of distinct ways to match the same input.

TrailEntry

A trail entry showing two ways through the pattern side by side.

TrailEntrySide

One side of a trail entry.

Enums

AnalysisLimit

The error reported for an unsafe result.

Error

An input error from a public entry point.

Score

A score. Finite carries the count; Infinite means unbounded backtracking.

Constants

DEFAULT_CASE_INSENSITIVE

Default case-insensitive mode.

DEFAULT_DOT_ALL

Default dot-all mode.

DEFAULT_MAX_SCORE

Default score cap.

DEFAULT_MAX_STEPS

Default step cap.

DEFAULT_MULTI_LINE

Default multi-line mode.

DEFAULT_UNICODE

Default unicode mode.

VERSION

The package version.

Functions

downgrade_pattern

Downgrades pattern if needed.

is_safe

Checks whether source and its inline flags are safe from ReDoS.

is_safe_pattern

Checks whether input_pattern is safe from ReDoS using explicit options.

to_friendly

Renders result as text.