Security Considerations¶

OntoLogos v0.4 handles untrusted input through JSON deserialization, OWL/RDF file parsing, and path validation. This document describes defaults and recommended practices.

JSON snapshots¶

Use Ontology::from_json for trusted snapshots. For untrusted input (user uploads, network payloads), prefer:

use ontologos_core::{Limits, Ontology};

let limits = Limits {
    max_json_bytes: 1_048_576, // 1 MiB
    ..Limits::default()
};
let ontology = Ontology::from_json_with_limits(json, limits)?;

Default limits¶

Limit	Default	Purpose
`max_json_bytes`	16 MiB	Prevent memory exhaustion
`max_entities`	1,000,000	Cap entity array size
`max_axioms`	10,000,000	Cap axiom array size
`max_iri_len`	8,192	Cap per-IRI string length
`max_class_operands`	10,000	Cap equivalent/disjoint operands

IRI validation¶

Only these schemes are accepted: http, https, urn.

Rejected:

javascript:, data:, and other schemes
Control characters (C0, DEL)
ASCII whitespace in IRIs
Relative IRIs (no scheme)

Format integrity¶

Format v1 is rejected — positional iris[] / entity index binding is unsafe for untrusted input
Format v2 keys axioms by IRI string
Unknown JSON fields on snapshot structs are rejected
Duplicate entity IRIs are rejected
Duplicate axioms are deduplicated on load (idempotent)

File loading (v0.2+)¶

ontologos_parser::validate_load_path canonicalizes paths and rejects traversal outside an optional base directory using path-component containment (not string-prefix matching).

load_ontology — no sandbox base (trusted local paths)
load_ontology_in(base, path) — constrain loads to stay under base (untrusted uploads)

Both validate the path, enforce ParseLimits, then parse via horned-owl. Sandboxed loads open the file once with O_NOFOLLOW (Unix) and sniff plus parse from the same file descriptor so a symlink swap between validation and read cannot escape the base directory.

Default parse limits¶

Limit	Default	Purpose
`max_file_bytes`	64 MiB	Cap ontology file size on disk
`max_axioms`	10,000,000	Cap stored axioms during mapping
`max_entities`	1,000,000	Cap registered entities during mapping

Use load_ontology_with_limits for untrusted uploads.

Skipped axioms and parser warnings are recorded in ParseMeta but do not fail the load. Review parse_meta.warnings when accepting user-supplied ontologies.

Reporting issues¶

Report security vulnerabilities privately — see Security policy (not public GitHub issues).