Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

use fixed authentication tag length of 16 octets in AES GCM decryption #126

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

use fixed authentication tag length of 16 octets in AES GCM decryption #126

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions src/jwe.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1225,6 +1225,12 @@ static bool _cjose_jwe_decrypt_dat_a256gcm(cjose_jwe_t *jwe, cjose_err *err)
goto _cjose_jwe_decrypt_dat_a256gcm_fail;
}

if (jwe->enc_auth_tag.raw_len != 16)
{
CJOSE_ERROR(err, CJOSE_ERR_CRYPTO);
goto _cjose_jwe_decrypt_dat_aes_gcm_fail;
}

// set the expected GCM-mode authentication tag
if (EVP_CIPHER_CTX_ctrl(ctx, CJOSE_EVP_CTRL_GCM_SET_TAG, jwe->enc_auth_tag.raw_len, jwe->enc_auth_tag.raw) != 1)
{
Expand Down
58 changes: 58 additions & 0 deletions test/check_jwe.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -809,6 +809,63 @@ START_TEST(test_cjose_jwe_decrypt_aes)
}
END_TEST

START_TEST(test_cjose_jwe_decrypt_aes_gcm)
{
cjose_err err;

const char *key = JWK_OCT_32;
const char *plain1 = "Live long and prosper.";
char *compact1 = "eyJhbGciOiAiZGlyIiwgImVuYyI6ICJBMjU2R0NNIn0..Du_9fxxV-zrReaWC.aS_rpokeuxkaPc2sykcQDCQuJCYoww.GpeKGEqd8KQ0v6JNea5aSA";
char *compact2 = "eyJhbGciOiAiZGlyIiwgImVuYyI6ICJBMjU2R0NNIn0..Du_9fxxV-zrReaWC.aS_rpokeuxkaPc2sykcQDCQuJCYoww.Gp";

cjose_jwk_t *jwk = cjose_jwk_import(key, strlen(key), &err);
ck_assert_msg(NULL != jwk,
"cjose_jwk_import failed: "
"%s, file: %s, function: %s, line: %ld",
err.message, err.file, err.function, err.line);

cjose_jwe_t *jwe1 = cjose_jwe_import(compact1, strlen(compact1), &err);
ck_assert_msg(NULL != jwe1,
"cjose_jwe_import failed: "
"%s, file: %s, function: %s, line: %ld",
err.message, err.file, err.function, err.line);

uint8_t *plain2 = NULL;
size_t plain2_len = 0;
plain2 = cjose_jwe_decrypt(jwe1, jwk, &plain2_len, &err);
ck_assert_msg(NULL != plain2,
"cjose_jwe_decrypt failed: "
"%s, file: %s, function: %s, line: %ld",
err.message, err.file, err.function, err.line);

ck_assert_msg(plain2_len == strlen(plain1),
"length of decrypted plaintext does not match length of original, "
"expected: %lu, found: %lu",
strlen(plain1), plain2_len);
ck_assert_msg(strncmp(plain1, plain2, plain2_len) == 0, "decrypted plaintext does not match encrypted plaintext");

cjose_get_dealloc()(plain2);
cjose_jwe_release(jwe1);

cjose_jwe_t *jwe2 = cjose_jwe_import(compact2, strlen(compact2), &err);
ck_assert_msg(NULL != jwe2,
"cjose_jwe_import failed: "
"%s, file: %s, function: %s, line: %ld",
err.message, err.file, err.function, err.line);

uint8_t *plain3 = NULL;
size_t plain3_len = 0;
plain3 = cjose_jwe_decrypt(jwe2, jwk, &plain3_len, &err);
ck_assert_msg(NULL == plain3,
"cjose_jwe_decrypt succeeded where it should have failed: "
"%s, file: %s, function: %s, line: %ld",
err.message, err.file, err.function, err.line);

cjose_jwe_release(jwe2);
cjose_jwk_release(jwk);
}
END_TEST

START_TEST(test_cjose_jwe_decrypt_rsa)
{
struct cjose_jwe_decrypt_rsa
Expand Down Expand Up @@ -1210,6 +1267,7 @@ Suite *cjose_jwe_suite()
tcase_add_test(tc_jwe, test_cjose_jwe_self_encrypt_self_decrypt_large);
tcase_add_test(tc_jwe, test_cjose_jwe_self_encrypt_self_decrypt_many);
tcase_add_test(tc_jwe, test_cjose_jwe_decrypt_aes);
tcase_add_test(tc_jwe, test_cjose_jwe_decrypt_aes_gcm);
tcase_add_test(tc_jwe, test_cjose_jwe_decrypt_rsa);
tcase_add_test(tc_jwe, test_cjose_jwe_encrypt_with_bad_header);
tcase_add_test(tc_jwe, test_cjose_jwe_encrypt_with_bad_key);
Expand Down