UDAInstitute/odutag

Cryptographic integrity labeler for heritage objects. HMAC-SHA-256 output encoded through Yoruba base-20 numerals and Ifá Odu structure — tamper-evident tags rooted in West African epistemology. Browser-only, no server, no data transmission. # OduTag · Cryptographic Integrity Labeler **Developed by the UDA Institute** *Forensic Heritage Tools · West African Cosmological Framework* --- ## What is OduTag? OduTag is a cryptographic integrity labeling system for heritage objects, evidence, and archival records. It generates tamper-evident tags by combining: - **HMAC-SHA-256** — a cryptographically sound message authentication code - **Yoruba base-20 encoding** — numerical expression rooted in the Yoruba counting system, where values 15–19 are expressed as subtractive forms (e.g., 20-5 for 15) - **AES S-box diffusion** — non-linear bit substitution for additional avalanche effect - **Odu index derivation** — a 0–255 reference value derived through S-box substitution of the HMAC output A generated tag takes the form: ``` YOR-3,20-4,3,8,11 | ODU-154 ``` This tag is uniquely derived from the object's identifier and any metadata bound at the time of generation. Any subsequent alteration to the identifier or bound metadata will produce a different tag, making tampering or corruption detectable on verification. --- ## Intellectual Framework OduTag encodes its integrity verification through a mathematical system indigenous to West Africa. The Yoruba numerical system — base-20, with subtractive construction for values 15–19 — is one of the most sophisticated indigenous counting systems on the African continent. The Odu reference system draws on the structural logic of Ifá divination, in which 256 Odu govern the full range of human and cosmological possibility. The choice to route cryptographic output through these frameworks is not ornamental. It is a philosophical position: that West African epistemic systems are fully capable of bearing the weight of contemporary forensic and archival practice. OduTag is developed under the West African Cosmological Framework (W.A.C.F.) of the UDA Institute. --- ## Technical Specification | Component | Detail | |-----------|--------| | Core primitive | HMAC-SHA-256 …