1 files changed, 158 insertions, 0 deletions
diff --git a/platform/linux-generic/arch/x86/odp_random.h b/platform/linux-generic/arch/x86/odp_random.h
new file mode 100644
index 000000000..14551f47e
--- /dev/null
+++ b/platform/linux-generic/arch/x86/odp_random.h
@@ -0,0 +1,158 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright (c) 2021 Nokia
+ */
+
+/*
+ * These functions implement ODP_RANDOM_CRYPTO random data using rdrand [1],
+ * and ODP_RANDOM_TRUE random data using rdseed [1], via compiler builtin
+ * functions.
+ *
+ * Note that there may be issues with the quality or security of rdrand and
+ * rdseed. [2]
+ *
+ * [1] Intel Digital Random Number Generator (DRNG) Software Implementation
+ *     Guide. John P Mechalas, 17 October 2018.
+ *     https://www.intel.com/content/www/us/en/developer/articles/guide/intel-digital-random-number-generator-drng-software-implementation-guide.html
+ *
+ * [2] RDRAND. Wikipedia, 29 September 2021.
+ *     https://en.wikipedia.org/wiki/RDRAND#Reception
+ */
+
+#ifndef ODP_X86_RANDOM_H_
+#define ODP_X86_RANDOM_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <odp/api/spec/random.h>
+
+#include <stdint.h>
+
+odp_random_kind_t _odp_random_max_kind_generic(void);
+int32_t _odp_random_true_data_generic(uint8_t *buf, uint32_t len);
+int32_t _odp_random_crypto_data_generic(uint8_t *buf, uint32_t len);
+
+#ifdef __RDRND__
+
+static inline int _odp_random_max_kind(void)
+{
+#ifdef __RDSEED__
+	return ODP_RANDOM_TRUE;
+#else
+	return ODP_RANDOM_CRYPTO;
+#endif
+}
+
+#else
+
+static inline int _odp_random_max_kind(void)
+{
+	return _odp_random_max_kind_generic();
+}
+
+#endif
+
+#ifdef __RDSEED__
+
+static inline int32_t _odp_random_true_data(uint8_t *buf, uint32_t len)
+{
+#ifdef __x86_64__
+	for (uint32_t i = 0; i < len / 8; i++) {
+		while (!__builtin_ia32_rdseed_di_step((unsigned long long *)buf))
+			;
+		buf += 8;
+	}
+
+	if (len & 4) {
+		while (!__builtin_ia32_rdseed_si_step((unsigned int *)buf))
+			;
+		buf += 4;
+	}
+#else
+	for (uint32_t i = 0; i < len / 4; i++) {
+		while (!__builtin_ia32_rdseed_si_step((unsigned int *)buf))
+			;
+		buf += 4;
+	}
+#endif
+	if (len & 2) {
+		while (!__builtin_ia32_rdseed_hi_step((unsigned short int *)buf))
+			;
+		buf += 2;
+	}
+
+	if (len & 1) {
+		uint16_t w;
+
+		while (!__builtin_ia32_rdseed_hi_step(&w))
+			;
+		*((uint8_t *)buf) = w & 0xff;
+	}
+
+	return len;
+}
+
+#else
+
+static inline int32_t _odp_random_true_data(uint8_t *buf, uint32_t len)
+{
+	return _odp_random_true_data_generic(buf, len);
+}
+
+#endif
+
+#ifdef __RDRND__
+
+static inline int32_t _odp_random_crypto_data(uint8_t *buf, uint32_t len)
+{
+#ifdef __x86_64__
+	for (uint32_t i = 0; i < len / 8; i++) {
+		while (!__builtin_ia32_rdrand64_step((unsigned long long *)buf))
+			;
+		buf += 8;
+	}
+
+	if (len & 4) {
+		while (!__builtin_ia32_rdrand32_step((unsigned int *)buf))
+			;
+		buf += 4;
+	}
+#else
+	for (uint32_t i = 0; i < len / 4; i++) {
+		while (!__builtin_ia32_rdrand32_step((unsigned int *)buf))
+			;
+		buf += 4;
+	}
+#endif
+	if (len & 2) {
+		while (!__builtin_ia32_rdrand16_step((unsigned short int *)buf))
+			;
+		buf += 2;
+	}
+
+	if (len & 1) {
+		uint16_t w;
+
+		while (!__builtin_ia32_rdrand16_step(&w))
+			;
+		*((uint8_t *)buf) = w & 0xff;
+	}
+
+	return len;
+}
+
+#else
+
+static inline int32_t _odp_random_crypto_data(uint8_t *buf, uint32_t len)
+{
+	return _odp_random_crypto_data_generic(buf, len);
+}
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif