HQC

Algorithm type: Key encapsulation mechanism.
Main cryptographic assumption: Syndrome decoding of structure codes (Hamming Quasi-Cyclic).
Principal submitters: Carlos Aguilar Melchor, Nicolas Aragon, Slim Bettaieb, Olivier Blazy, Jurjen Bos, Jean-Christophe Deneuville, Philippe Gaborit, Edoardo Persichetti, Jean-Marc Robert, Pascal Véron, Gilles Zémor, Loïc Bidoux.
Authors' website: https://pqc-hqc.org/
Specification version: NIST Round 3 submission.
Implementation source: 89d3461336, which takes it from:
- https://github.com/jschanck/package-pqclean/tree/29f79e72/hqc, which takes it from:
- submission 2020-10-01 at https://pqc-hqc.org/implementation.html
Implementation license (SPDX-Identifier): Public domain.

Parameter set summary

Parameter set	Security model	Claimed NIST Level	Public key size (bytes)	Secret key size (bytes)	Ciphertext size (bytes)	Shared secret size (bytes)
HQC-128	IND-CCA2	1	2249	2289	4481	64
HQC-192	IND-CCA2	3	4522	4562	9026	64
HQC-256	IND-CCA2	5	7245	7285	14469	64

Identifier in upstream	Supported architecture(s)	Supported operating system(s)	CPU extension(s) used	No branching-on-secrets claimed?	No branching-on-secrets checked by valgrind?	Large stack usage?
clean	All	All	None	True	True	False
avx2	x86_64	Linux,Darwin	AVX2,BMI1,PCLMULQDQ	False	True	False

Are implementations chosen based on runtime CPU feature detection? Yes.

Identifier in upstream	Supported architecture(s)	Supported operating system(s)	CPU extension(s) used	No branching-on-secrets claimed?	No branching-on-secrets checked by valgrind?	Large stack usage?
clean	All	All	None	True	True	False
avx2	x86_64	Linux,Darwin	AVX2,BMI1,PCLMULQDQ	False	True	False

Are implementations chosen based on runtime CPU feature detection? Yes.

Identifier in upstream	Supported architecture(s)	Supported operating system(s)	CPU extension(s) used	No branching-on-secrets claimed?	No branching-on-secrets checked by valgrind?	Large stack usage?
clean	All	All	None	True	True	False
avx2	x86_64	Linux,Darwin	AVX2,BMI1,PCLMULQDQ	False	True	False

Are implementations chosen based on runtime CPU feature detection? Yes.