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SEC 1 & GEC 1. Core ECC Specifications Simon Blake-Wilson Certicom Research. Overview. Introduction to SEC 1 and GEC 1 Review of ECC standards SEC 1 GEC 1 Summary. SEC 1 & GEC 1. Core ECC specifications SEC 1: cryptographic schemes GEC 1: recommended curves Encourage deployment
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SEC 1 & GEC 1 Core ECC Specifications Simon Blake-Wilson Certicom Research
Overview • Introduction to SEC 1 and GEC 1 • Review of ECC standards • SEC 1 • GEC 1 • Summary
SEC 1 & GEC 1 • Core ECC specifications • SEC 1: cryptographic schemes • GEC 1: recommended curves • Encourage deployment • Facilitate interoperability • Encourage analysis
Other ECC Standards • Many efforts to standardize ECC • Creating problems: • Diverse standards • Plethora of options • Difficult to keep up!
ANSI X9.62 • ECDSA signatures • 80 bits minimum security • Fp and F2^m • Polynomial and normal bases for F2m • Point representation options • Approved by ANSI
ANSI X9.63 • ECDH, ECMQV, and EC Unified Model key agreement • ECAES (Bellare-Rogaway) encryption • Many flavors: static-ephemeral, cofactor, key confirmation, 1-2-3 pass. • Core math built (mainly) on X9.62.
IEEE P1363 • ECDSA, ECNR signatures • ECDH, ECMQV, and EC Unified Model key agreement • Very general specification • Extra options for: hashing, point representation, security levels, etc.
IEEE P1363A • Legacy ECAES encryption • Proposals to include encryption, signcryption, identification, implicit certificates, etc. • Impetus?
NIST • ECDSA FIPS • Built on ANSI X9.62 • F2^m m composite removed • F2^m basis restricted? • “Recommended” curves?
ISO • ISO 15946 specifies ECC • Part 1: General • Part 2: Signatures • Part 3: Key establishment • Options, options, options! • Timeline?
ATM Forum • Generic ATM security standard • ECDSA-like signatures • ECDH key agreement • Point compression • Future uncertain?
IPSec • ECC included in Oakley document • ECDH key agreement • x-coordinate point representation • Default curves over F2^155 and F2^185 • Attempts to add ECDSA and align with ANSI and IEEE.
WAP • WTLS for wireless devices • ECDSA signatures for certificates • ECDH for key agreement • Following IEEE P1363 • Strong recommendations on point compression and curves. • Version 1.1? last week
Other Standards • Cellular: TIA CDPD and 3G • Content protection: 5C and USB • De facto: PKCS 13 • IETF: SSL/TLS, PKIX, etc. • Payments: SET, etc.
SEC 1 • Core ECC “Standard” • Profile other standards • Find path which restricts options but ensures conformance and efficiency • Signatures, encryption, and key agreement
SEC 1 Signatures • Only ECDSA • Generic hash function support • Octet oriented • IEEE truncation at export strength • Relationship to ANSI X9.62, IEEE P1363
SEC 1 Encryption • Only ECAES (Bellare-Rogaway) • Generic symmetric encryption, MACing, key derivation • Standard and cofactor ECDH options • Relationship to ANSI X9.63, IEEE P1363A
SEC 1 Key Agreement • ECDH and ECMQV • Generic key derivation • Standard and cofactor ECDH • Only cofactor ECMQV • Relationship to ANSI X9.63, IEEE P1363
SEC 1 “Mathematics” • Curves over Fp and F2^m • Major restrictions on p and m • Major restrictions on F2^m basis: one or two polynomial bases allowed, no normal bases. • Any curve allowed over supported fields • Compressed and uncompressed point representations allowed
SEC 1 “Components” • Parameter generation and validation • Key generation and validation • Standard and cofactor ECDH primitives with point at infinity check • ECMQV primitive with bit flip and point at infinity check • Hash functions: SHA-1
SEC 1 “Components” (cont.) • Key derivation functions: X9.63 • MACs: HMAC with SHA-1. 80 or 160 bit output • Symmetric encryption: “XOR” or TDES in CBC mode. Fixed IV and keying convention
GEC 1 • SEC 1 allows any “secure” curve over supported fields • GEC 1 supplies recommended curves at supported security levels • Crucial for interoperability • Recommended and supplementary curves • Evolve as NIST’s plans and other standards evolve
Summary • SEC 1 and GEC 1 are designed to provide core foundation for SEC series • Provide an interoperability path through murky waters • Going forward: comments, expert review, modification, ratification, ...