crypto/x509-utils: Add helper functions for DIAG 320 subcode 2
Introduce new helper functions to extract certificate metadata: qcrypto_x509_check_cert_times() - validates the certificate's validity period against the current time qcrypto_x509_get_cert_key_id() - extracts the key ID from the certificate qcrypto_x509_check_ecc_curve_p521() - determines the ECC public key algorithm uses P-521 curve These functions provide support for metadata extraction and validity checking for X.509 certificates. Signed-off-by: Zhuoying Cai <zycai@linux.ibm.com> Acked-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Link: https://lore.kernel.org/qemu-devel/20260730214624.2328883-9-zycai@linux.ibm.com Signed-off-by: Eric Farman <farman@linux.ibm.com>
Zhuoying Cai committed
Jul 30, 2026 at 17:45 UTC
e8317c4c9f68c23b6e993efc71d26facafdfaa69
2 files changed
+287
crypto/x509-utils.c
+236
@@ -27,6 +27,16 @@ static const int qcrypto_to_gnutls_hash_alg_map[QCRYPTO_HASH_ALGO__MAX] = {
27
[QCRYPTO_HASH_ALGO_RIPEMD160] = GNUTLS_DIG_RMD160,
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};
29
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+static const int qcrypto_to_gnutls_keyid_flags_map[] = {
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+ [QCRYPTO_HASH_ALGO_MD5] = -1,
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+ [QCRYPTO_HASH_ALGO_SHA1] = GNUTLS_KEYID_USE_SHA1,
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+ [QCRYPTO_HASH_ALGO_SHA224] = -1,
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+ [QCRYPTO_HASH_ALGO_SHA256] = GNUTLS_KEYID_USE_SHA256,
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+ [QCRYPTO_HASH_ALGO_SHA384] = -1,
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+ [QCRYPTO_HASH_ALGO_SHA512] = GNUTLS_KEYID_USE_SHA512,
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+ [QCRYPTO_HASH_ALGO_RIPEMD160] = -1,
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+};
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+
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int qcrypto_get_x509_cert_fingerprint(uint8_t *cert, size_t size,
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QCryptoHashAlgo alg,
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uint8_t *result,
@@ -122,6 +132,210 @@ cleanup:
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return ret;
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}
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+int qcrypto_x509_check_cert_times(uint8_t *cert, size_t size, Error **errp)
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+{
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+ int rc;
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+ int ret = -1;
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+ gnutls_x509_crt_t crt;
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+ gnutls_datum_t datum = {.data = cert, .size = size};
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+ time_t now = time(NULL);
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+ time_t exp_time;
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+ time_t act_time;
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+
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+ if (now == ((time_t)-1)) {
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+ error_setg_errno(errp, errno, "Cannot get current time");
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+ return ret;
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+ }
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+
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+ rc = gnutls_x509_crt_init(&crt);
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+ if (rc < 0) {
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+ error_setg(errp, "Failed to initialize certificate: %s", gnutls_strerror(rc));
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+ return ret;
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+ }
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+
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+ rc = gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM);
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+ if (rc != 0) {
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+ error_setg(errp, "Failed to import certificate: %s", gnutls_strerror(rc));
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+ goto cleanup;
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+ }
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+
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+ exp_time = gnutls_x509_crt_get_expiration_time(crt);
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+ if (exp_time == ((time_t)-1)) {
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+ error_setg(errp, "Failed to get certificate expiration time");
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+ goto cleanup;
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+ }
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+ if (exp_time < now) {
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+ error_setg(errp, "The certificate has expired");
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+ goto cleanup;
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+ }
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+
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+ act_time = gnutls_x509_crt_get_activation_time(crt);
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+ if (act_time == ((time_t)-1)) {
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+ error_setg(errp, "Failed to get certificate activation time");
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+ goto cleanup;
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+ }
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+ if (act_time > now) {
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+ error_setg(errp, "The certificate is not yet active");
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+ goto cleanup;
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+ }
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+
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+ ret = 0;
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+
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+cleanup:
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+ gnutls_x509_crt_deinit(crt);
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+ return ret;
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+}
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+
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+static int qcrypto_x509_get_pk_algorithm(uint8_t *cert, size_t size, Error **errp)
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+{
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+ int rc;
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+ int ret = -1;
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+ unsigned int bits;
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+ gnutls_x509_crt_t crt;
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+ gnutls_datum_t datum = {.data = cert, .size = size};
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+
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+ rc = gnutls_x509_crt_init(&crt);
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+ if (rc < 0) {
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+ error_setg(errp, "Failed to initialize certificate: %s", gnutls_strerror(rc));
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+ return ret;
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+ }
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+
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+ rc = gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM);
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+ if (rc != 0) {
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+ error_setg(errp, "Failed to import certificate: %s", gnutls_strerror(rc));
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+ goto cleanup;
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+ }
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+
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+ rc = gnutls_x509_crt_get_pk_algorithm(crt, &bits);
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+ if (rc < 0) {
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+ error_setg(errp, "Unknown public key algorithm %d", rc);
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+ goto cleanup;
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+ }
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+
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+ ret = rc;
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+
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+cleanup:
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+ gnutls_x509_crt_deinit(crt);
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+ return ret;
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+}
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+
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+int qcrypto_x509_get_cert_key_id(uint8_t *cert, size_t size,
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+ QCryptoHashAlgo hash_alg,
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+ uint8_t **result,
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+ size_t *resultlen,
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+ Error **errp)
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+{
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+ int rc;
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+ int ret = -1;
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+ gnutls_x509_crt_t crt;
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+ gnutls_datum_t datum = {.data = cert, .size = size};
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+
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+ if (hash_alg >= G_N_ELEMENTS(qcrypto_to_gnutls_hash_alg_map)) {
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+ error_setg(errp, "Unknown hash algorithm %d", hash_alg);
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+ return ret;
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+ }
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+
238
+ if (hash_alg >= G_N_ELEMENTS(qcrypto_to_gnutls_keyid_flags_map) ||
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+ qcrypto_to_gnutls_keyid_flags_map[hash_alg] == -1) {
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+ error_setg(errp, "Unsupported key id flag %d", hash_alg);
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+ return ret;
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+ }
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+
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+ rc = gnutls_x509_crt_init(&crt);
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+ if (rc < 0) {
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+ error_setg(errp, "Failed to initialize certificate: %s", gnutls_strerror(rc));
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+ return ret;
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+ }
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+
250
+ rc = gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM);
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+ if (rc != 0) {
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+ error_setg(errp, "Failed to import certificate: %s", gnutls_strerror(rc));
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+ goto cleanup;
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+ }
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+
256
+ *resultlen = gnutls_hash_get_len(qcrypto_to_gnutls_hash_alg_map[hash_alg]);
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+ if (*resultlen == 0) {
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+ error_setg(errp, "Failed to get hash algorithm length: %s", gnutls_strerror(rc));
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+ goto cleanup;
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+ }
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+
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+ *result = g_malloc0(*resultlen);
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+ if (gnutls_x509_crt_get_key_id(crt,
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+ qcrypto_to_gnutls_keyid_flags_map[hash_alg],
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+ *result, resultlen) != 0) {
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+ error_setg(errp, "Failed to get key ID from certificate");
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+ g_clear_pointer(result, g_free);
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+ goto cleanup;
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+ }
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+
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+ ret = 0;
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+
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+cleanup:
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+ gnutls_x509_crt_deinit(crt);
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+ return ret;
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+}
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+
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+static int qcrypto_x509_get_ecc_curve(uint8_t *cert, size_t size, Error **errp)
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+{
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+ int rc;
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+ int ret = -1;
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+ gnutls_x509_crt_t crt;
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+ gnutls_datum_t datum = {.data = cert, .size = size};
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+ gnutls_ecc_curve_t curve_id;
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+ gnutls_datum_t x = {.data = NULL, .size = 0};
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+ gnutls_datum_t y = {.data = NULL, .size = 0};
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+
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+ rc = gnutls_x509_crt_init(&crt);
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+ if (rc < 0) {
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+ error_setg(errp, "Failed to initialize certificate: %s", gnutls_strerror(rc));
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+ return ret;
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+ }
293
+
294
+ rc = gnutls_x509_crt_import(crt, &datum, GNUTLS_X509_FMT_PEM);
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+ if (rc != 0) {
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+ error_setg(errp, "Failed to import certificate: %s", gnutls_strerror(rc));
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+ goto cleanup;
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+ }
299
+
300
+ rc = gnutls_x509_crt_get_pk_ecc_raw(crt, &curve_id, &x, &y);
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+ if (rc != 0) {
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+ error_setg(errp, "Failed to get ECC public key curve: %s", gnutls_strerror(rc));
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+ goto cleanup;
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+ }
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+
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+ ret = curve_id;
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+
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+cleanup:
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+ gnutls_x509_crt_deinit(crt);
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+ g_free(x.data);
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+ g_free(y.data);
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+ return ret;
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+}
314
+
315
+int qcrypto_x509_check_ecc_curve_p521(uint8_t *cert, size_t size, Error **errp)
316
+{
317
+ int algo;
318
+ int curve_id;
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+
320
+ algo = qcrypto_x509_get_pk_algorithm(cert, size, errp);
321
+ if (algo != GNUTLS_PK_ECDSA) {
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+ return 0;
323
+ }
324
+
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+ curve_id = qcrypto_x509_get_ecc_curve(cert, size, errp);
326
+ if (curve_id == -1) {
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+ error_setg(errp, "Failed to get ECC curve");
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+ return -1;
329
+ }
330
+
331
+ if (curve_id == GNUTLS_ECC_CURVE_INVALID) {
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+ error_setg(errp, "Invalid ECC curve");
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+ return -1;
334
+ }
335
+
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+ return curve_id == GNUTLS_ECC_CURVE_SECP521R1;
337
+}
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+
339
#else /* ! CONFIG_GNUTLS */
340
341
int qcrypto_get_x509_cert_fingerprint(uint8_t *cert, size_t size,
@@ -143,4 +357,26 @@ int qcrypto_x509_convert_cert_der(uint8_t *cert, size_t size,
357
return -1;
358
}
359
360
+int qcrypto_x509_check_cert_times(uint8_t *cert, size_t size, Error **errp)
361
+{
362
+ error_setg(errp, "GNUTLS is required to get certificate times");
363
+ return -1;
364
+}
365
+
366
+int qcrypto_x509_get_cert_key_id(uint8_t *cert, size_t size,
367
+ QCryptoHashAlgo hash_alg,
368
+ uint8_t **result,
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+ size_t *resultlen,
370
+ Error **errp)
371
+{
372
+ error_setg(errp, "GNUTLS is required to get key ID");
373
+ return -1;
374
+}
375
+
376
+int qcrypto_x509_check_ecc_curve_p521(uint8_t *cert, size_t size, Error **errp)
377
+{
378
+ error_setg(errp, "GNUTLS is required to determine ecc curve");
379
+ return -1;
380
+}
381
+
382
#endif /* ! CONFIG_GNUTLS */
include/crypto/x509-utils.h
+51
@@ -40,4 +40,55 @@ int qcrypto_x509_convert_cert_der(uint8_t *cert, size_t size,
40
size_t *resultlen,
41
Error **errp);
42
43
+/**
44
+ * qcrypto_x509_check_cert_times
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+ * @cert: pointer to the raw certificate data
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+ * @size: size of the certificate
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+ * @errp: error pointer
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+ *
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+ * Check whether the activation and expiration times of @cert
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+ * are valid at the current time.
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+ *
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+ * Returns: 0 if the certificate times are valid,
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+ * -1 on error.
54
+ */
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+int qcrypto_x509_check_cert_times(uint8_t *cert, size_t size, Error **errp);
56
+
57
+/**
58
+ * qcrypto_x509_get_cert_key_id
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+ * @cert: pointer to the raw certificate data
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+ * @size: size of the certificate
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+ * @hash_alg: the hash algorithm flag
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+ * @result: output location for the allocated buffer for key ID
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+ * (the function allocates memory which must be freed by the caller)
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+ * @resultlen: pointer to the size of the buffer
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+ * (will be updated with the actual size of key id)
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+ * @errp: error pointer
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+ *
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+ * Retrieve the key ID from the @cert based on the specified @hash_alg.
69
+ *
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+ * Returns: 0 if key ID was successfully stored in @result,
71
+ * -1 on error.
72
+ */
73
+int qcrypto_x509_get_cert_key_id(uint8_t *cert, size_t size,
74
+ QCryptoHashAlgo hash_alg,
75
+ uint8_t **result,
76
+ size_t *resultlen,
77
+ Error **errp);
78
+
79
+/**
80
+ * qcrypto_x509_check_ecc_curve_p521
81
+ * @cert: pointer to the raw certificate data
82
+ * @size: size of the certificate
83
+ * @errp: error pointer
84
+ *
85
+ * Determine whether the ECC public key in the given certificate uses the P-521
86
+ * curve.
87
+ *
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+ * Returns: 0 if ECC public key does not use P521 curve.
89
+ * 1 if ECC public key uses P521 curve.
90
+ * -1 on error.
91
+ */
92
+int qcrypto_x509_check_ecc_curve_p521(uint8_t *cert, size_t size, Error **errp);
93
+
94
#endif