Overhaul ML-KEM regress once more

Implement a file parser that drives a state machine to extract the test data
from the .txt files and manages the parsed data. Comments and empty lines are
ignored. The code currently assumes that instruction lines are at the start
of the file (which isn't generally true) and only supports two line types for
now. This is good enough for all the ML-KEM tests but should be easy enough
to extend.

Once all data for a test case is parsed in the expected order, a test handler
is called which can retrieve the test data via a simple API and throw warnings
and errors with information on the test case line number, etc.

Merge the tests into three programs: one parsing the .txt files and running
the corresponding test cases, a unit test and the iteration tests. Deduplicate
the actual test code and let the caller pass in an object containing the
API functions, private keys and arrays that need to be different between the
768 version and the 1024 version. This way we don't have two sets of half a
dozen .c files differing only in 3 or 4 occurrences of 768 and 1024.

All this will also make it a lot easier to hook these tests into portable.

1 files changed, 101 insertions, 182 deletions

diff --git a/src/regress/lib/libcrypto/mlkem/mlkem_unittest.c b/src/regress/lib/libcrypto/mlkem/mlkem_unittest.c
index 18bf128bea..3f7e2886b9 100644
--- a/src/regress/lib/libcrypto/mlkem/mlkem_unittest.c
+++ b/src/regress/lib/libcrypto/mlkem/mlkem_unittest.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: mlkem_unittest.c,v 1.4 2024/12/20 00:07:12 tb Exp $ */
+/*      $OpenBSD: mlkem_unittest.c,v 1.5 2024/12/26 00:04:24 tb Exp $ */
 /*
  * Copyright (c) 2024 Google Inc.
  * Copyright (c) 2024 Bob Beck <beck@obtuse.com>
@@ -27,13 +27,28 @@
 
 #include "mlkem_tests_util.h"
 
+struct unittest_ctx {
+        void *priv;
+        void *pub;
+        void *priv2;
+        void *pub2;
+        uint8_t *encoded_public_key;
+        size_t encoded_public_key_len;
+        uint8_t *ciphertext;
+        size_t ciphertext_len;
+        mlkem_decap_fn decap;
+        mlkem_encap_fn encap;
+        mlkem_generate_key_fn generate_key;
+        mlkem_parse_private_key_fn parse_private_key;
+        mlkem_parse_public_key_fn parse_public_key;
+        mlkem_encode_private_key_fn encode_private_key;
+        mlkem_encode_public_key_fn encode_public_key;
+        mlkem_public_from_private_fn public_from_private;
+};
+
 static int
-MlKem768UnitTest(void)
+MlKemUnitTest(struct unittest_ctx *ctx)
 {
-        struct MLKEM768_private_key priv = { 0 }, priv2 = { 0 };
-        struct MLKEM768_public_key pub = { 0 }, pub2 = { 0 };
-        uint8_t encoded_public_key[MLKEM768_PUBLIC_KEY_BYTES];
-        uint8_t ciphertext[MLKEM768_CIPHERTEXT_BYTES];
         uint8_t shared_secret1[MLKEM_SHARED_SECRET_BYTES];
         uint8_t shared_secret2[MLKEM_SHARED_SECRET_BYTES];
         uint8_t first_two_bytes[2];
@@ -42,22 +57,22 @@ MlKem768UnitTest(void)
         CBS cbs;
         int failed = 0;
 
-        MLKEM768_generate_key(encoded_public_key, NULL, &priv);
+        ctx->generate_key(ctx->encoded_public_key, NULL, ctx->priv);
 
-        memcpy(first_two_bytes, encoded_public_key, sizeof(first_two_bytes));
-        memset(encoded_public_key, 0xff, sizeof(first_two_bytes));
+        memcpy(first_two_bytes, ctx->encoded_public_key, sizeof(first_two_bytes));
+        memset(ctx->encoded_public_key, 0xff, sizeof(first_two_bytes));
 
-        CBS_init(&cbs, encoded_public_key, sizeof(encoded_public_key));
+        CBS_init(&cbs, ctx->encoded_public_key, ctx->encoded_public_key_len);
 
         /* Parsing should fail because the first coefficient is >= kPrime. */
-        if (MLKEM768_parse_public_key(&pub, &cbs)) {
-                warnx("MLKEM768_parse_public_key should have failed");
+        if (ctx->parse_public_key(ctx->pub, &cbs)) {
+                warnx("parse_public_key should have failed");
                 failed |= 1;
         }
 
-        memcpy(encoded_public_key, first_two_bytes, sizeof(first_two_bytes));
-        CBS_init(&cbs, encoded_public_key, sizeof(encoded_public_key));
-        if (!MLKEM768_parse_public_key(&pub, &cbs)) {
+        memcpy(ctx->encoded_public_key, first_two_bytes, sizeof(first_two_bytes));
+        CBS_init(&cbs, ctx->encoded_public_key, ctx->encoded_public_key_len);
+        if (!ctx->parse_public_key(ctx->pub, &cbs)) {
                 warnx("MLKEM768_parse_public_key");
                 failed |= 1;
         }
@@ -67,16 +82,16 @@ MlKem768UnitTest(void)
                 failed |= 1;
         }
 
-        if (!mlkem768_encode_public_key(&pub, &tmp_buf, &tmp_buf_len)) {
+        if (!ctx->encode_public_key(ctx->pub, &tmp_buf, &tmp_buf_len)) {
                 warnx("encode_public_key");
                 failed |= 1;
         }
-        if (sizeof(encoded_public_key) != tmp_buf_len) {
-                warnx("mlkem768 encoded public key lengths differ");
+        if (ctx->encoded_public_key_len != tmp_buf_len) {
+                warnx("encoded public key lengths differ");
                 failed |= 1;
         }
 
-        if (compare_data(encoded_public_key, tmp_buf, tmp_buf_len, 768,
+        if (compare_data(ctx->encoded_public_key, tmp_buf, tmp_buf_len,
             "encoded public keys") != 0) {
                 warnx("compare_data");
                 failed |= 1;
@@ -84,17 +99,17 @@ MlKem768UnitTest(void)
         free(tmp_buf);
         tmp_buf = NULL;
 
-        MLKEM768_public_from_private(&pub2, &priv);
-        if (!mlkem768_encode_public_key(&pub2, &tmp_buf, &tmp_buf_len)) {
-                warnx("mlkem768_encode_public_key");
+        ctx->public_from_private(ctx->pub2, ctx->priv);
+        if (!ctx->encode_public_key(ctx->pub2, &tmp_buf, &tmp_buf_len)) {
+                warnx("encode_public_key");
                 failed |= 1;
         }
-        if (sizeof(encoded_public_key) != tmp_buf_len) {
-                warnx("mlkem768 encoded public key lengths differ");
+        if (ctx->encoded_public_key_len != tmp_buf_len) {
+                warnx("encoded public key lengths differ");
                 failed |= 1;
         }
 
-        if (compare_data(encoded_public_key, tmp_buf, tmp_buf_len, 768,
+        if (compare_data(ctx->encoded_public_key, tmp_buf, tmp_buf_len,
             "encoded public keys") != 0) {
                 warnx("compare_data");
                 failed |= 1;
@@ -102,7 +117,7 @@ MlKem768UnitTest(void)
         free(tmp_buf);
         tmp_buf = NULL;
 
-        if (!mlkem768_encode_private_key(&priv, &encoded_private_key,
+        if (!ctx->encode_private_key(ctx->priv, &encoded_private_key,
             &encoded_private_key_len)) {
                 warnx("mlkem768_encode_private_key");
                 failed |= 1;
@@ -113,7 +128,7 @@ MlKem768UnitTest(void)
         CBS_init(&cbs, encoded_private_key, encoded_private_key_len);
 
         /*  Parsing should fail because the first coefficient is >= kPrime. */
-        if (MLKEM768_parse_private_key(&priv2, &cbs)) {
+        if (ctx->parse_private_key(ctx->priv2, &cbs)) {
                 warnx("MLKEM768_parse_private_key should have failed");
                 failed |= 1;
         }
@@ -121,162 +136,22 @@ MlKem768UnitTest(void)
         memcpy(encoded_private_key, first_two_bytes, sizeof(first_two_bytes));
         CBS_init(&cbs, encoded_private_key, encoded_private_key_len);
 
-        if (!MLKEM768_parse_private_key(&priv2, &cbs)) {
+        if (!ctx->parse_private_key(ctx->priv2, &cbs)) {
                 warnx("MLKEM768_parse_private_key");
                 failed |= 1;
         }
 
-        if (!mlkem768_encode_private_key(&priv2, &tmp_buf, &tmp_buf_len)) {
-                warnx("mlkem768_encode_private_key");
-                failed |= 1;
-        }
-
-        if (encoded_private_key_len != tmp_buf_len) {
-                warnx("mlkem768 encode private key lengths differ");
-                failed |= 1;
-        }
-
-        if (compare_data(encoded_private_key, tmp_buf, tmp_buf_len, 768,
-            "encoded private key") != 0) {
-                warnx("compare_data");
-                failed |= 1;
-        }
-
-        free(tmp_buf);
-        tmp_buf = NULL;
-
-        MLKEM768_encap(ciphertext, shared_secret1, &pub);
-        MLKEM768_decap(shared_secret2, ciphertext, MLKEM768_CIPHERTEXT_BYTES,
-            &priv);
-        if (compare_data(shared_secret1, shared_secret2, MLKEM_SHARED_SECRET_BYTES,
-            768, "shared secrets with priv") != 0) {
-                warnx("compare_data");
-                failed |= 1;
-        }
-
-        MLKEM768_decap(shared_secret2, ciphertext, MLKEM768_CIPHERTEXT_BYTES,
-            &priv2);
-        if (compare_data(shared_secret1, shared_secret2, MLKEM_SHARED_SECRET_BYTES,
-            768, "shared secrets with priv2") != 0) {
-                warnx("compare_data");
-                failed |= 1;
-        }
-
-        free(encoded_private_key);
-
-        return failed;
-}
-
-static int
-MlKem1024UnitTest(void)
-{
-        struct MLKEM1024_private_key priv = { 0 }, priv2 = { 0 };
-        struct MLKEM1024_public_key pub = { 0 }, pub2 = { 0 };
-        uint8_t encoded_public_key[MLKEM1024_PUBLIC_KEY_BYTES];
-        uint8_t ciphertext[MLKEM1024_CIPHERTEXT_BYTES];
-        uint8_t shared_secret1[MLKEM_SHARED_SECRET_BYTES];
-        uint8_t shared_secret2[MLKEM_SHARED_SECRET_BYTES];
-        uint8_t first_two_bytes[2];
-        uint8_t *encoded_private_key = NULL, *tmp_buf = NULL;
-        size_t encoded_private_key_len, tmp_buf_len;
-        CBS cbs;
-        int failed = 0;
-
-        MLKEM1024_generate_key(encoded_public_key, NULL, &priv);
-
-        memcpy(first_two_bytes, encoded_public_key, sizeof(first_two_bytes));
-        memset(encoded_public_key, 0xff, sizeof(first_two_bytes));
-
-        CBS_init(&cbs, encoded_public_key, sizeof(encoded_public_key));
-
-        /* Parsing should fail because the first coefficient is >= kPrime. */
-        if (MLKEM1024_parse_public_key(&pub, &cbs)) {
-                warnx("MLKEM1024_parse_public_key should have failed");
-                failed |= 1;
-        }
-
-        memcpy(encoded_public_key, first_two_bytes, sizeof(first_two_bytes));
-        CBS_init(&cbs, encoded_public_key, sizeof(encoded_public_key));
-        if (!MLKEM1024_parse_public_key(&pub, &cbs)) {
-                warnx("MLKEM1024_parse_public_key");
-                failed |= 1;
-        }
-
-        if (CBS_len(&cbs) != 0u) {
-                warnx("CBS_len must be 0");
-                failed |= 1;
-        }
-
-        if (!mlkem1024_encode_public_key(&pub, &tmp_buf, &tmp_buf_len)) {
-                warnx("encode_public_key");
-                failed |= 1;
-        }
-        if (sizeof(encoded_public_key) != tmp_buf_len) {
-                warnx("mlkem1024 encoded public key lengths differ");
-                failed |= 1;
-        }
-
-        if (compare_data(encoded_public_key, tmp_buf, tmp_buf_len, 1024,
-            "encoded public keys") != 0) {
-                warnx("compare_data");
-                failed |= 1;
-        }
-        free(tmp_buf);
-        tmp_buf = NULL;
-
-        MLKEM1024_public_from_private(&pub2, &priv);
-        if (!mlkem1024_encode_public_key(&pub2, &tmp_buf, &tmp_buf_len)) {
-                warnx("mlkem1024_encode_public_key");
-                failed |= 1;
-        }
-        if (sizeof(encoded_public_key) != tmp_buf_len) {
-                warnx("mlkem1024 encoded public key lengths differ");
-                failed |= 1;
-        }
-
-        if (compare_data(encoded_public_key, tmp_buf, tmp_buf_len, 1024,
-            "encoded public keys") != 0) {
-                warnx("compare_data");
-                failed |= 1;
-        }
-        free(tmp_buf);
-        tmp_buf = NULL;
-
-        if (!mlkem1024_encode_private_key(&priv, &encoded_private_key,
-            &encoded_private_key_len)) {
-                warnx("mlkem1024_encode_private_key");
-                failed |= 1;
-        }
-
-        memcpy(first_two_bytes, encoded_private_key, sizeof(first_two_bytes));
-        memset(encoded_private_key, 0xff, sizeof(first_two_bytes));
-        CBS_init(&cbs, encoded_private_key, encoded_private_key_len);
-
-        /*  Parsing should fail because the first coefficient is >= kPrime. */
-        if (MLKEM1024_parse_private_key(&priv2, &cbs)) {
-                warnx("MLKEM1024_parse_private_key should have failed");
-                failed |= 1;
-        }
-
-        memcpy(encoded_private_key, first_two_bytes, sizeof(first_two_bytes));
-        CBS_init(&cbs, encoded_private_key, encoded_private_key_len);
-
-        if (!MLKEM1024_parse_private_key(&priv2, &cbs)) {
-                warnx("MLKEM1024_parse_private_key");
-                failed |= 1;
-        }
-
-        if (!mlkem1024_encode_private_key(&priv2, &tmp_buf, &tmp_buf_len)) {
-                warnx("mlkem1024_encode_private_key");
+        if (!ctx->encode_private_key(ctx->priv2, &tmp_buf, &tmp_buf_len)) {
+                warnx("encode_private_key");
                 failed |= 1;
         }
 
         if (encoded_private_key_len != tmp_buf_len) {
-                warnx("mlkem1024 encode private key lengths differ");
+                warnx("encode private key lengths differ");
                 failed |= 1;
         }
 
-        if (compare_data(encoded_private_key, tmp_buf, tmp_buf_len, 1024,
+        if (compare_data(encoded_private_key, tmp_buf, tmp_buf_len,
             "encoded private key") != 0) {
                 warnx("compare_data");
                 failed |= 1;
@@ -285,19 +160,19 @@ MlKem1024UnitTest(void)
         free(tmp_buf);
         tmp_buf = NULL;
 
-        MLKEM1024_encap(ciphertext, shared_secret1, &pub);
-        MLKEM1024_decap(shared_secret2, ciphertext, MLKEM1024_CIPHERTEXT_BYTES,
-            &priv);
+        ctx->encap(ctx->ciphertext, shared_secret1, ctx->pub);
+        ctx->decap(shared_secret2, ctx->ciphertext, ctx->ciphertext_len,
+            ctx->priv);
         if (compare_data(shared_secret1, shared_secret2, MLKEM_SHARED_SECRET_BYTES,
-            1024, "shared secrets with priv") != 0) {
+            "shared secrets with priv") != 0) {
                 warnx("compare_data");
                 failed |= 1;
         }
 
-        MLKEM1024_decap(shared_secret2, ciphertext, MLKEM1024_CIPHERTEXT_BYTES,
-            &priv2);
+        ctx->decap(shared_secret2, ctx->ciphertext, ctx->ciphertext_len,
+            ctx->priv2);
         if (compare_data(shared_secret1, shared_secret2, MLKEM_SHARED_SECRET_BYTES,
-            1024, "shared secrets with priv2") != 0) {
+            "shared secrets with priv2") != 0) {
                 warnx("compare_data");
                 failed |= 1;
         }
@@ -308,12 +183,56 @@ MlKem1024UnitTest(void)
 }
 
 int
-main(int argc, char **argv)
+main(void)
 {
+        struct MLKEM768_private_key mlkem768_priv, mlkem768_priv2;
+        struct MLKEM768_public_key mlkem768_pub, mlkem768_pub2;
+        uint8_t mlkem768_encoded_public_key[MLKEM768_PUBLIC_KEY_BYTES];
+        uint8_t mlkem768_ciphertext[MLKEM768_CIPHERTEXT_BYTES];
+        struct unittest_ctx mlkem768_test = {
+                .priv = &mlkem768_priv,
+                .pub = &mlkem768_pub,
+                .priv2 = &mlkem768_priv2,
+                .pub2 = &mlkem768_pub2,
+                .encoded_public_key = mlkem768_encoded_public_key,
+                .encoded_public_key_len = sizeof(mlkem768_encoded_public_key),
+                .ciphertext = mlkem768_ciphertext,
+                .ciphertext_len = sizeof(mlkem768_ciphertext),
+                .decap = mlkem768_decap,
+                .encap = mlkem768_encap,
+                .generate_key = mlkem768_generate_key,
+                .parse_private_key = mlkem768_parse_private_key,
+                .parse_public_key = mlkem768_parse_public_key,
+                .encode_private_key = mlkem768_encode_private_key,
+                .encode_public_key = mlkem768_encode_public_key,
+                .public_from_private = mlkem768_public_from_private,
+        };
+        struct MLKEM1024_private_key mlkem1024_priv, mlkem1024_priv2;
+        struct MLKEM1024_public_key mlkem1024_pub, mlkem1024_pub2;
+        uint8_t mlkem1024_encoded_public_key[MLKEM1024_PUBLIC_KEY_BYTES];
+        uint8_t mlkem1024_ciphertext[MLKEM1024_CIPHERTEXT_BYTES];
+        struct unittest_ctx mlkem1024_test = {
+                .priv = &mlkem1024_priv,
+                .pub = &mlkem1024_pub,
+                .priv2 = &mlkem1024_priv2,
+                .pub2 = &mlkem1024_pub2,
+                .encoded_public_key = mlkem1024_encoded_public_key,
+                .encoded_public_key_len = sizeof(mlkem1024_encoded_public_key),
+                .ciphertext = mlkem1024_ciphertext,
+                .ciphertext_len = sizeof(mlkem1024_ciphertext),
+                .decap = mlkem1024_decap,
+                .encap = mlkem1024_encap,
+                .generate_key = mlkem1024_generate_key,
+                .parse_private_key = mlkem1024_parse_private_key,
+                .parse_public_key = mlkem1024_parse_public_key,
+                .encode_private_key = mlkem1024_encode_private_key,
+                .encode_public_key = mlkem1024_encode_public_key,
+                .public_from_private = mlkem1024_public_from_private,
+        };
         int failed = 0;
 
-        failed |= MlKem768UnitTest();
-        failed |= MlKem1024UnitTest();
+        failed |= MlKemUnitTest(&mlkem768_test);
+        failed |= MlKemUnitTest(&mlkem1024_test);
 
         return failed;
 }