test: fix self-talk pkey offload test for openssl-3.0-fips (#5175)

Author: lrstewart

codebuild/spec/buildspec_openssl3fips.yml

@@ -35,4 +35,4 @@ phases:
     commands:
       - export CTEST_PARALLEL_LEVEL=$(nproc)
       # openssl3fips is still a work-in-progress. Not all tests pass.
-      - make -C build test -- ARGS="-E 's2n_self_talk_offload_signing_test'"
+      - make -C build test

tests/unit/s2n_self_talk_offload_signing_test.c

@@ -19,11 +19,8 @@
 
 #define S2N_TEST_CERT_MEM 5000
 
-int s2n_ecdsa_sign_digest(const struct s2n_pkey *priv, struct s2n_blob *digest, struct s2n_blob *signature);
-int s2n_rsa_pkcs1v15_sign_digest(const struct s2n_pkey *priv, s2n_hash_algorithm hash_alg,
-        struct s2n_blob *digest, struct s2n_blob *signature);
-int s2n_rsa_pss_sign_digest(const struct s2n_pkey *priv, s2n_hash_algorithm hash_alg,
-        struct s2n_blob *digest_in, struct s2n_blob *signature_out);
+S2N_RESULT s2n_async_pkey_op_copy_hash_state_for_testing(struct s2n_async_pkey_op *op,
+        struct s2n_hash_state *copy);
 
 struct s2n_async_pkey_op *pkey_op = NULL;
 struct s2n_connection *pkey_op_conn = NULL;
@@ -34,6 +31,36 @@ static int s2n_test_async_pkey_cb(struct s2n_connection *conn, struct s2n_async_
     return S2N_SUCCESS;
 }
 
+static S2N_RESULT s2n_test_pkey_sign(const struct s2n_pkey *pkey,
+        struct s2n_blob *input, struct s2n_blob *output,
+        s2n_signature_algorithm sig_alg)
+{
+    /* We're going to cheat a little here.
+     * Our pkey signing methods operate on hash states, not raw digests.
+     * So we need to use the hash state from the operation directly.
+     */
+
+    /* First, make sure that the actual input matches the digest
+     * produced by digesting the hash state.
+     * This proves the two are equivalent and we can use the hash state.
+     */
+    DEFER_CLEANUP(struct s2n_blob digest = { 0 }, s2n_free);
+    RESULT_GUARD_POSIX(s2n_alloc(&digest, input->size));
+    DEFER_CLEANUP(struct s2n_hash_state digest_copy = { 0 }, s2n_hash_free);
+    RESULT_GUARD_POSIX(s2n_hash_new(&digest_copy));
+    RESULT_GUARD(s2n_async_pkey_op_copy_hash_state_for_testing(pkey_op, &digest_copy));
+    RESULT_GUARD_POSIX(s2n_hash_digest(&digest_copy, digest.data, digest.size));
+    EXPECT_BYTEARRAY_EQUAL(digest.data, input->data, input->size);
+
+    /* Use the hash state instead of the input to calculate the signature */
+    DEFER_CLEANUP(struct s2n_hash_state sign_copy = { 0 }, s2n_hash_free);
+    RESULT_GUARD_POSIX(s2n_hash_new(&sign_copy));
+    RESULT_GUARD(s2n_async_pkey_op_copy_hash_state_for_testing(pkey_op, &sign_copy));
+    RESULT_GUARD_POSIX(s2n_pkey_sign(pkey, sig_alg, &sign_copy, output));
+
+    return S2N_RESULT_OK;
+}
+
 static S2N_RESULT s2n_async_pkey_sign(struct s2n_cert_chain_and_key *complete_chain)
 {
     RESULT_ENSURE_REF(pkey_op);
@@ -73,14 +100,9 @@ static S2N_RESULT s2n_async_pkey_sign(struct s2n_cert_chain_and_key *complete_ch
     if (op_type == S2N_ASYNC_DECRYPT) {
         output.size = S2N_TLS_SECRET_LEN;
         RESULT_GUARD_POSIX(s2n_pkey_decrypt(complete_chain->private_key, &input, &output));
-    } else if (sig_alg == S2N_TLS_SIGNATURE_ECDSA) {
-        RESULT_GUARD_POSIX(s2n_ecdsa_sign_digest(complete_chain->private_key, &input, &output));
-    } else if (sig_alg == S2N_TLS_SIGNATURE_RSA) {
-        RESULT_GUARD_POSIX(s2n_rsa_pkcs1v15_sign_digest(
-                complete_chain->private_key, sig_scheme->hash_alg, &input, &output));
-    } else if (sig_alg == S2N_TLS_SIGNATURE_RSA_PSS_RSAE) {
-        RESULT_GUARD_POSIX(s2n_rsa_pss_sign_digest(
-                complete_chain->private_key, sig_scheme->hash_alg, &input, &output));
+    } else if (op_type == S2N_ASYNC_SIGN) {
+        RESULT_GUARD(s2n_test_pkey_sign(complete_chain->private_key, &input, &output,
+                sig_scheme->sig_alg));
     } else {
         RESULT_BAIL(S2N_ERR_UNIMPLEMENTED);
     }

tls/s2n_async_pkey.c

@@ -632,3 +632,12 @@ static S2N_RESULT s2n_async_pkey_op_set_output_sign(struct s2n_async_pkey_op *op
 
     return S2N_RESULT_OK;
 }
+
+S2N_RESULT s2n_async_pkey_op_copy_hash_state_for_testing(struct s2n_async_pkey_op *op,
+        struct s2n_hash_state *copy)
+{
+    RESULT_ENSURE_REF(op);
+    RESULT_ENSURE_EQ(op->type, S2N_ASYNC_SIGN);
+    RESULT_GUARD_POSIX(s2n_hash_copy(copy, &op->op.sign.digest));
+    return S2N_RESULT_OK;
+}