commit 0196f4886a9aa44ecb3d3a19465cca422ff2c0f9
author Gilles Peskine <Gilles.Peskine@arm.com> Thu Feb 01 22:33:06 2024 +0100
committer Gilles Peskine <Gilles.Peskine@arm.com> Mon Feb 12 17:00:48 2024 +0100
tree 084c8fe981ee35353d854939f575de9da60729b0
parent ede909f99ab6e6a958a41e365251c2a1d2c4ed4d

Fix mbedtls_pk_get_bitlen() for RSA with non-byte-aligned sizes

Add non-regression tests. Update some test functions to not assume that
byte_length == bit_length / 8.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>

tests/suites/test_suite_pk.function

diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index c17037f..2111926 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -155,7 +155,7 @@
     TEST_ASSERT(strcmp(mbedtls_pk_get_name(&pk), name) == 0);
 
     TEST_ASSERT(mbedtls_pk_get_bitlen(&pk) == bitlen);
-    TEST_ASSERT(mbedtls_pk_get_len(&pk) == bitlen / 8);
+    TEST_ASSERT(mbedtls_pk_get_len(&pk) == (bitlen + 7) / 8);
 
     TEST_ASSERT(mbedtls_pk_can_do(&pk, MBEDTLS_PK_ECKEY) == 1);
     TEST_ASSERT(mbedtls_pk_can_do(&pk, MBEDTLS_PK_ECDSA) == 1);
@@ -683,7 +683,7 @@
     TEST_ASSERT(mbedtls_pk_setup(&pk, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == 0);
     rsa = mbedtls_pk_rsa(pk);
 
-    rsa->len = mod / 8;
+    rsa->len = (mod + 7) / 8;
     TEST_ASSERT(mbedtls_test_read_mpi(&rsa->N, input_N) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&rsa->E, input_E) == 0);
 
@@ -731,7 +731,7 @@
     TEST_ASSERT(mbedtls_pk_setup(&pk, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == 0);
     rsa = mbedtls_pk_rsa(pk);
 
-    rsa->len = mod / 8;
+    rsa->len = (mod + 7) / 8;
     TEST_ASSERT(mbedtls_test_read_mpi(&rsa->N, input_N) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&rsa->E, input_E) == 0);
 
@@ -1004,7 +1004,7 @@
     TEST_ASSERT(mbedtls_pk_setup(&pk, mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == 0);
     rsa = mbedtls_pk_rsa(pk);
 
-    rsa->len = mod / 8;
+    rsa->len = (mod + 7) / 8;
     TEST_ASSERT(mbedtls_test_read_mpi(&rsa->N, input_N) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&rsa->E, input_E) == 0);
 
@@ -1053,9 +1053,12 @@
     TEST_ASSERT(mbedtls_test_read_mpi(&P, input_P) == 0);
     TEST_ASSERT(mbedtls_test_read_mpi(&Q, input_Q) == 0);
     TEST_ASSERT(mbedtls_rsa_import(rsa, &N, &P, &Q, NULL, &E) == 0);
-    TEST_ASSERT(mbedtls_rsa_get_len(rsa) == (size_t) (mod / 8));
+    TEST_EQUAL(mbedtls_rsa_get_len(rsa), (mod + 7) / 8);
     TEST_ASSERT(mbedtls_rsa_complete(rsa) == 0);
 
+    TEST_EQUAL(mbedtls_pk_get_bitlen(&pk), mod);
+    TEST_EQUAL(mbedtls_pk_get_len(&pk), (mod + 7) / 8);
+
     /* decryption test */
     memset(output, 0, sizeof(output));
     olen = 0;