1 files changed, 90 insertions, 0 deletions
diff --git a/programs/fuzz/fuzz_pubkey.c b/programs/fuzz/fuzz_pubkey.c
new file mode 100644
index 00000000000..0b153b14d7d
--- /dev/null
+++ b/programs/fuzz/fuzz_pubkey.c
@@ -0,0 +1,90 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include "mbedtls/pk.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
+{
+#ifdef MBEDTLS_PK_PARSE_C
+    int ret;
+    mbedtls_pk_context pk;
+
+    mbedtls_pk_init(&pk);
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+    psa_status_t status = psa_crypto_init();
+    if (status != PSA_SUCCESS) {
+        goto exit;
+    }
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+    ret = mbedtls_pk_parse_public_key(&pk, Data, Size);
+    if (ret == 0) {
+#if defined(MBEDTLS_RSA_C)
+        if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_RSA) {
+            mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
+            mbedtls_rsa_context *rsa;
+
+            mbedtls_mpi_init(&N); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
+            mbedtls_mpi_init(&D); mbedtls_mpi_init(&E); mbedtls_mpi_init(&DP);
+            mbedtls_mpi_init(&DQ); mbedtls_mpi_init(&QP);
+
+            rsa = mbedtls_pk_rsa(pk);
+            if (mbedtls_rsa_export(rsa, &N, NULL, NULL, NULL, &E) != 0) {
+                abort();
+            }
+            if (mbedtls_rsa_export(rsa, &N, &P, &Q, &D, &E) != MBEDTLS_ERR_RSA_BAD_INPUT_DATA) {
+                abort();
+            }
+            if (mbedtls_rsa_export_crt(rsa, &DP, &DQ, &QP) != MBEDTLS_ERR_RSA_BAD_INPUT_DATA) {
+                abort();
+            }
+
+            mbedtls_mpi_free(&N); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
+            mbedtls_mpi_free(&D); mbedtls_mpi_free(&E); mbedtls_mpi_free(&DP);
+            mbedtls_mpi_free(&DQ); mbedtls_mpi_free(&QP);
+
+        } else
+#endif
+#if defined(MBEDTLS_ECP_C)
+        if (mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY ||
+            mbedtls_pk_get_type(&pk) == MBEDTLS_PK_ECKEY_DH) {
+            mbedtls_ecp_keypair *ecp = mbedtls_pk_ec(pk);
+            mbedtls_ecp_group_id grp_id = mbedtls_ecp_keypair_get_group_id(ecp);
+            const mbedtls_ecp_curve_info *curve_info =
+                mbedtls_ecp_curve_info_from_grp_id(grp_id);
+
+            /* If the curve is not supported, the key should not have been
+             * accepted. */
+            if (curve_info == NULL) {
+                abort();
+            }
+
+            /* It's a public key, so the private value should not have
+             * been changed from its initialization to 0. */
+            mbedtls_mpi d;
+            mbedtls_mpi_init(&d);
+            if (mbedtls_ecp_export(ecp, NULL, &d, NULL) != 0) {
+                abort();
+            }
+            if (mbedtls_mpi_cmp_int(&d, 0) != 0) {
+                abort();
+            }
+            mbedtls_mpi_free(&d);
+        } else
+#endif
+        {
+            /* The key is valid but is not of a supported type.
+             * This should not happen. */
+            abort();
+        }
+    }
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+exit:
+    mbedtls_psa_crypto_free();
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+    mbedtls_pk_free(&pk);
+#else
+    (void) Data;
+    (void) Size;
+#endif //MBEDTLS_PK_PARSE_C
+
+    return 0;
+}