libseckey: Fix error checking when building ECDSA signatures

OpenSSL function i2d_ECDSA_SIG() returns a negative value in case of
an error, so check the returned length for <= zero to detect an error.

Reported-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
This commit is contained in:
Ingo Franzki
2023-03-08 16:24:44 +01:00
committed by Jan Höppner
parent e621d2dfa2
commit fcfd4a6158

View File

@@ -776,6 +776,10 @@ int SK_UTIL_build_ecdsa_signature(const unsigned char *raw_sig,
bn_s = NULL;
der_len = i2d_ECDSA_SIG(ec_sig, NULL);
if (der_len <= 0) {
rc = -EIO;
goto out;
}
if (sig == NULL) {
*sig_len = der_len;
@@ -788,13 +792,14 @@ int SK_UTIL_build_ecdsa_signature(const unsigned char *raw_sig,
memset(sig, 0, *sig_len);
der = sig;
*sig_len = i2d_ECDSA_SIG(ec_sig, &der);
if (*sig_len == 0) {
der_len = i2d_ECDSA_SIG(ec_sig, &der);
if (der_len <= 0) {
rc = -EIO;
goto out;
}
*sig_len = der_len;
out:
if (ec_sig != NULL)
ECDSA_SIG_free(ec_sig);