On 18/09/2025 01.21, Zhuoying Cai wrote:
Introduce new helper functions for x509 certificate, which will be used
by the certificate store:
qcrypto_x509_convert_cert_der() - converts a certificate from PEM to DER format
These functions provide support for certificate format conversion.
Signed-off-by: Zhuoying Cai <[email protected]>
---
crypto/x509-utils.c | 50 +++++++++++++++++++++++++++++++++++++
include/crypto/x509-utils.h | 20 +++++++++++++++
2 files changed, 70 insertions(+)
diff --git a/crypto/x509-utils.c b/crypto/x509-utils.c
index 6176a88653..5d43b0ec96 100644
--- a/crypto/x509-utils.c
+++ b/crypto/x509-utils.c
@@ -81,6 +81,47 @@ int qcrypto_get_x509_cert_fingerprint(uint8_t *cert, size_t
size,
return ret;
}
+int qcrypto_x509_convert_cert_der(uint8_t *cert, size_t size,
+ uint8_t **result, size_t *resultlen,
+ Error **errp)
+{
+ int ret = -1;
+ int rc;
+ gnutls_x509_crt_t crt;
+ gnutls_datum_t datum = {.data = cert, .size = size};
+ gnutls_datum_t datum_der = {.data = NULL, .size = 0};
+
+ rc = gnutls_x509_crt_init(&crt);
+ if (rc < 0) {
+ error_setg(errp, "Failed to initialize certificate: %s",
gnutls_strerror(rc));
+ return ret;
+ }
+
+ rc = gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM);
+ if (rc != 0) {
+ error_setg(errp, "Failed to import certificate: %s",
gnutls_strerror(rc));
+ goto cleanup;
+ }
+
+ rc = gnutls_x509_crt_export2(crt, GNUTLS_X509_FMT_DER, &datum_der);
+ if (rc != 0) {
+ error_setg(errp, "Failed to convert certificate to DER format: %s",
+ gnutls_strerror(rc));
+ goto cleanup;
+ }
+
+ *result = g_new0(uint8_t, datum_der.size);
+ *resultlen = datum_der.size;
+ memcpy(*result, datum_der.data, datum_der.size);
+
+ ret = 0;
+
+cleanup:
+ gnutls_x509_crt_deinit(crt);
+ gnutls_free(datum_der.data);
+ return ret;
+}
+
#else /* ! CONFIG_GNUTLS */
int qcrypto_get_x509_cert_fingerprint(uint8_t *cert, size_t size,
@@ -93,4 +134,13 @@ int qcrypto_get_x509_cert_fingerprint(uint8_t *cert, size_t
size,
return -1;
}
+int qcrypto_x509_convert_cert_der(uint8_t *cert, size_t size,
+ uint8_t **result,
+ size_t *resultlen,
+ Error **errp)
+{
+ error_setg(errp, "GNUTLS is required to export X.509 certificate");
+ return -1;
+}
+
#endif /* ! CONFIG_GNUTLS */
diff --git a/include/crypto/x509-utils.h b/include/crypto/x509-utils.h
index 1e99661a71..4239e3e55a 100644
--- a/include/crypto/x509-utils.h
+++ b/include/crypto/x509-utils.h
@@ -19,4 +19,24 @@ int qcrypto_get_x509_cert_fingerprint(uint8_t *cert, size_t
size,
size_t *resultlen,
Error **errp);
+/**
+ * qcrypto_x509_convert_cert_der
+ * @cert: pointer to the raw certificate data in PEM format
+ * @size: size of the certificate
+ * @result: output location for the allocated buffer for the certificate in
DER format
+ (the function allocates memory which must be freed by the caller)
Please try to fit the comments into the 80 columns boundary.
Thanks,
Thomas
+ * @resultlen: pointer to the size of the buffer
+ (will be updated with the actual size of the DER-encoded
certificate)
+ * @errp: error pointer
+ *
+ * Convert the given @cert from PEM to DER format.
+ *
+ * Returns: 0 on success,
+ * -1 on error.
+ */
+int qcrypto_x509_convert_cert_der(uint8_t *cert, size_t size,
+ uint8_t **result,
+ size_t *resultlen,
+ Error **errp);
+
#endif
