extract notrandombytes into a separate file

Signed-off-by: Thing-han, Lim <[email protected]>

hal/notrandombytes.c

@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "randombytes.h"
+#include <string.h>
+
+static uint32_t seed[32] = {3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9, 3,
+                            2, 3, 8, 4, 6, 2, 6, 4, 3, 3, 8, 3, 2, 7, 9, 5
+                           };
+static uint32_t in[12];
+static uint8_t out_buf[sizeof(uint32_t) * 16];
+static int32_t outleft = 0;
+
+#define ROTATE(x, b) (((x) << (b)) | ((x) >> (32 - (b))))
+#define MUSH(i, b) x = t[i] += (((x ^ seed[i]) + sum) ^ ROTATE(x, b));
+
+static void surf(uint32_t out[8]) {
+    uint32_t t[12];
+    uint32_t x;
+    uint32_t sum = 0;
+    int32_t r;
+    int32_t i;
+    int32_t loop;
+
+    for (i = 0; i < 12; ++i) {
+        t[i] = in[i] ^ seed[12 + i];
+    }
+    for (i = 0; i < 8; ++i) {
+        out[i] = seed[24 + i];
+    }
+    x = t[11];
+    for (loop = 0; loop < 2; ++loop) {
+        for (r = 0; r < 16; ++r) {
+            sum += 0x9e3779b9;
+            MUSH(0, 5)
+            MUSH(1, 7)
+            MUSH(2, 9)
+            MUSH(3, 13)
+            MUSH(4, 5)
+            MUSH(5, 7)
+            MUSH(6, 9)
+            MUSH(7, 13)
+            MUSH(8, 5)
+            MUSH(9, 7)
+            MUSH(10, 9)
+            MUSH(11, 13)
+        }
+        for (i = 0; i < 8; ++i) {
+            out[i] ^= t[i + 4];
+        }
+    }
+}
+
+void randombytes_regen(void);
+void randombytes_regen(void) {
+    uint32_t out[8];
+    if (!++in[0]) {
+        if (!++in[1]) {
+            if (!++in[2]) {
+                ++in[3];
+            }
+        }
+    }
+    surf(out);
+    memcpy(out_buf, out, sizeof(out));
+    if (!++in[0]) {
+        if (!++in[1]) {
+            if (!++in[2]) {
+                ++in[3];
+            }
+        }
+    }
+    surf(out);
+    memcpy(out_buf + sizeof(out), out, sizeof(out));
+    outleft = sizeof(out_buf);
+}
+
+int randombytes(uint8_t *buf, size_t xlen) {
+    while (xlen > 0) {
+        if (!outleft) {
+            randombytes_regen();
+        }
+        *buf = out_buf[--outleft];
+        ++buf;
+        --xlen;
+    }
+    return 0;
+}

hal/randombytes.c

@@ -1,9 +1,6 @@
 // SPDX-License-Identifier: Apache-2.0
 #include "randombytes.h"
 
-#if defined(STM32F2) || defined(STM32F4) ||                                    \
-defined(STM32L4R5ZI) && !defined(MPS2_AN386)
-
 #include <libopencm3/stm32/rng.h>
 
 int randombytes(uint8_t *obuf, size_t len) {
@@ -28,94 +25,3 @@ int randombytes(uint8_t *obuf, size_t len) {
 
     return 0;
 }
-
-#else
-
-#warning Using a non-random randombytes
-
-#include <string.h>
-
-static uint32_t seed[32] = {3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9, 3,
-                            2, 3, 8, 4, 6, 2, 6, 4, 3, 3, 8, 3, 2, 7, 9, 5
-                           };
-static uint32_t in[12];
-static uint8_t out_buf[sizeof(uint32_t) * 16];
-static int32_t outleft = 0;
-
-#define ROTATE(x, b) (((x) << (b)) | ((x) >> (32 - (b))))
-#define MUSH(i, b) x = t[i] += (((x ^ seed[i]) + sum) ^ ROTATE(x, b));
-
-static void surf(uint32_t out[8]) {
-    uint32_t t[12];
-    uint32_t x;
-    uint32_t sum = 0;
-    int32_t r;
-    int32_t i;
-    int32_t loop;
-
-    for (i = 0; i < 12; ++i) {
-        t[i] = in[i] ^ seed[12 + i];
-    }
-    for (i = 0; i < 8; ++i) {
-        out[i] = seed[24 + i];
-    }
-    x = t[11];
-    for (loop = 0; loop < 2; ++loop) {
-        for (r = 0; r < 16; ++r) {
-            sum += 0x9e3779b9;
-            MUSH(0, 5)
-            MUSH(1, 7)
-            MUSH(2, 9)
-            MUSH(3, 13)
-            MUSH(4, 5)
-            MUSH(5, 7)
-            MUSH(6, 9)
-            MUSH(7, 13)
-            MUSH(8, 5)
-            MUSH(9, 7)
-            MUSH(10, 9)
-            MUSH(11, 13)
-        }
-        for (i = 0; i < 8; ++i) {
-            out[i] ^= t[i + 4];
-        }
-    }
-}
-
-void randombytes_regen(void);
-void randombytes_regen(void) {
-    uint32_t out[8];
-    if (!++in[0]) {
-        if (!++in[1]) {
-            if (!++in[2]) {
-                ++in[3];
-            }
-        }
-    }
-    surf(out);
-    memcpy(out_buf, out, sizeof(out));
-    if (!++in[0]) {
-        if (!++in[1]) {
-            if (!++in[2]) {
-                ++in[3];
-            }
-        }
-    }
-    surf(out);
-    memcpy(out_buf + sizeof(out), out, sizeof(out));
-    outleft = sizeof(out_buf);
-}
-
-int randombytes(uint8_t *buf, size_t xlen) {
-    while (xlen > 0) {
-        if (!outleft) {
-            randombytes_regen();
-        }
-        *buf = out_buf[--outleft];
-        ++buf;
-        --xlen;
-    }
-    return 0;
-}
-
-#endif

mk/mps2-an386.mk

@@ -39,7 +39,7 @@ LDFLAGS += \
 LIBHAL_SRC := \
 	hal/mps2/startup_MPS2.S \
 	hal/hal-mps2.c \
-	hal/randombytes.c
+	hal/notrandombytes.c
 
 obj/libpqm4hal.a: $(call objs,$(LIBHAL_SRC))
 obj/libpqm4hal.a: CPPFLAGS += -Ihal/mps2