lib/crypto: tests: Add KUnit tests for BLAKE2s

Add a KUnit test suite for BLAKE2s.  Most of the core test logic is in
the previously-added hash-test-template.h.  This commit just adds the
actual KUnit suite, commits the generated test vectors to the tree so
that gen-hash-testvecs.py won't have to be run at build time, and adds a
few BLAKE2s-specific test cases.

This is the replacement for blake2s-selftest, which an earlier commit
removed.  Improvements over blake2s-selftest include integration with
KUnit, more comprehensive test cases, and support for benchmarking.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250827151131.27733-13-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

1 files changed, 24 insertions, 3 deletions

diff --git a/scripts/crypto/gen-hash-testvecs.py b/scripts/crypto/gen-hash-testvecs.py
index 4ac927d40cf5..fc063f2ee95f 100755
--- a/scripts/crypto/gen-hash-testvecs.py
+++ b/scripts/crypto/gen-hash-testvecs.py
@@ -84,11 +84,16 @@ def print_c_struct_u8_array_field(name, value):
     print_bytes('\t\t\t', value, 8)
     print('\t\t},')
 
+def alg_digest_size_const(alg):
+    if alg == 'blake2s':
+        return 'BLAKE2S_HASH_SIZE'
+    return f'{alg.upper()}_DIGEST_SIZE'
+
 def gen_unkeyed_testvecs(alg):
     print('')
     print('static const struct {')
     print('\tsize_t data_len;')
-    print(f'\tu8 digest[{alg.upper()}_DIGEST_SIZE];')
+    print(f'\tu8 digest[{alg_digest_size_const(alg)}];')
     print('} hash_testvecs[] = {')
     for data_len in DATA_LENS:
         data = rand_bytes(data_len)
@@ -103,7 +108,7 @@ def gen_unkeyed_testvecs(alg):
     for data_len in range(len(data) + 1):
         hash_update(ctx, compute_hash(alg, data[:data_len]))
     print_static_u8_array_definition(
-            f'hash_testvec_consolidated[{alg.upper()}_DIGEST_SIZE]',
+            f'hash_testvec_consolidated[{alg_digest_size_const(alg)}]',
             hash_final(ctx))
 
 def gen_hmac_testvecs(alg):
@@ -119,6 +124,20 @@ def gen_hmac_testvecs(alg):
             f'hmac_testvec_consolidated[{alg.upper()}_DIGEST_SIZE]',
             ctx.digest())
 
+BLAKE2S_KEY_SIZE = 32
+BLAKE2S_HASH_SIZE = 32
+
+def gen_additional_blake2s_testvecs():
+    hashes = b''
+    for key_len in range(BLAKE2S_KEY_SIZE + 1):
+        for out_len in range(1, BLAKE2S_HASH_SIZE + 1):
+            h = hashlib.blake2s(digest_size=out_len, key=rand_bytes(key_len))
+            h.update(rand_bytes(100))
+            hashes += h.digest()
+    print_static_u8_array_definition(
+            'blake2s_keyed_testvec_consolidated[BLAKE2S_HASH_SIZE]',
+            compute_hash('blake2s', hashes))
+
 def gen_additional_poly1305_testvecs():
     key = b'\xff' * POLY1305_KEY_SIZE
     data = b''
@@ -141,7 +160,9 @@ alg = sys.argv[1]
 print('/* SPDX-License-Identifier: GPL-2.0-or-later */')
 print(f'/* This file was generated by: {sys.argv[0]} {" ".join(sys.argv[1:])} */')
 gen_unkeyed_testvecs(alg)
-if alg == 'poly1305':
+if alg == 'blake2s':
+    gen_additional_blake2s_testvecs()
+elif alg == 'poly1305':
     gen_additional_poly1305_testvecs()
 else:
     gen_hmac_testvecs(alg)