Fix backwards include of x509.h in oid.h
As agreed during the workshop, temporarily move definitions to oid.h even if
they might not semantically belong here, as a short-term measure allowing to
build libmbecrypto on its own (without X.509 files present in the source tree)
but still provide all the things Mbed TLS currently expects, and more
specifically preserve the API and ABI exposed by libmbedtls.
diff --git a/include/mbedtls/oid.h b/include/mbedtls/oid.h
index 6fbd018..afe7a81 100644
--- a/include/mbedtls/oid.h
+++ b/include/mbedtls/oid.h
@@ -43,13 +43,31 @@
#include "md.h"
#endif
-#if defined(MBEDTLS_X509_USE_C) || defined(MBEDTLS_X509_CREATE_C)
-#include "x509.h"
-#endif
-
#define MBEDTLS_ERR_OID_NOT_FOUND -0x002E /**< OID is not found. */
#define MBEDTLS_ERR_OID_BUF_TOO_SMALL -0x000B /**< output buffer is too small */
+/* This is for the benefit of X.509, but defined here in order to avoid
+ * having a "backwards" include of x.509.h here */
+/*
+ * X.509 extension types (internal, arbitrary values for bitsets)
+ */
+#define MBEDTLS_OID_X509_EXT_AUTHORITY_KEY_IDENTIFIER (1 << 0)
+#define MBEDTLS_OID_X509_EXT_SUBJECT_KEY_IDENTIFIER (1 << 1)
+#define MBEDTLS_OID_X509_EXT_KEY_USAGE (1 << 2)
+#define MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES (1 << 3)
+#define MBEDTLS_OID_X509_EXT_POLICY_MAPPINGS (1 << 4)
+#define MBEDTLS_OID_X509_EXT_SUBJECT_ALT_NAME (1 << 5)
+#define MBEDTLS_OID_X509_EXT_ISSUER_ALT_NAME (1 << 6)
+#define MBEDTLS_OID_X509_EXT_SUBJECT_DIRECTORY_ATTRS (1 << 7)
+#define MBEDTLS_OID_X509_EXT_BASIC_CONSTRAINTS (1 << 8)
+#define MBEDTLS_OID_X509_EXT_NAME_CONSTRAINTS (1 << 9)
+#define MBEDTLS_OID_X509_EXT_POLICY_CONSTRAINTS (1 << 10)
+#define MBEDTLS_OID_X509_EXT_EXTENDED_KEY_USAGE (1 << 11)
+#define MBEDTLS_OID_X509_EXT_CRL_DISTRIBUTION_POINTS (1 << 12)
+#define MBEDTLS_OID_X509_EXT_INIHIBIT_ANYPOLICY (1 << 13)
+#define MBEDTLS_OID_X509_EXT_FRESHEST_CRL (1 << 14)
+#define MBEDTLS_OID_X509_EXT_NS_CERT_TYPE (1 << 16)
+
/*
* Top level OID tuples
*/