pkg/micro-ecc: support boards without hwrng feature

pkg/micro-ecc/Makefile.dep

@@ -1 +0,0 @@
-FEATURES_REQUIRED += periph_hwrng

pkg/micro-ecc/README.md

@@ -0,0 +1,37 @@
+# Micro-ECC for RIOT
+
+This port of Micro-ECC to RIOT is based on the Micro-ECC
+[upstream](https://github.com/kmackay/micro-ecc) and adds `hwrng_read`
+(provided by RIOT) as the default RNG function if it is available on the target
+platform. This port also fixes a minor issue with unused variables in the
+upstream code.
+
+# Usage
+
+## Build
+
+Add
+```Makefile
+USEPKG += micro-ecc
+```
+to your Makefile.
+
+## Choosing the right API
+
+Before using the Micro-ECC library, you need to check the `Makefile.features`
+of your target board to see if `periph_hwrng` is provided.
+
+If it is provided, you may safely use `uECC_make_key` to generate ECDSA key
+pairs and call `uECC_sign`/`uECC_verify` to sign/verify the ECDSA signatures.
+
+If not, you cannot use `uECC_make_key` or `uECC_sign` APIs anymore. The ECDSA
+keys have to be generated on a platform with HWRNG support (e.g., `native`) and
+transferred to your target device. You need to use `uECC_sign_deterministic` to
+perform ECDSA deterministic signing (standardized by RFC 6979). You can still
+use `uECC_verify` to verify the signatures from both signing APIs.
+
+**WARNING** Calling `uECC_make_key` and `uECC_sign` APIs on platforms without
+HWRNG support will lead to compile failure.
+
+Examples of using these uECC APIs can be found in the `test` folder of the
+Micro-ECC upstream.

tests/pkg_micro-ecc-with-hwrng/Makefile

@@ -0,0 +1,10 @@
+APPLICATION = pkg_micro-ecc-with-hwrng
+include ../Makefile.tests_common
+
+FEATURES_REQUIRED = periph_hwrng
+
+USEPKG += micro-ecc
+
+CFLAGS += -DFEATURE_PERIPH_HWRNG
+
+include $(RIOTBASE)/Makefile.include

tests/pkg_micro-ecc-with-hwrng/main.c

@@ -0,0 +1,122 @@
+/*-
+ * Copyright 2014 Kenneth MacKay
+ * Copyright 2014 Frank Holtz
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+/**
+ * @file
+ * @brief       Check if the micro-ecc builds and working
+ *
+ * @author      Frank Holtz <frank-riot2015@holtznet.de>
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include "uECC.h"
+#include "periph/hwrng.h"
+
+#define TESTROUNDS  16
+
+int main(void)
+{
+    printf("micro-ecc compiled!\n");
+
+    const struct uECC_Curve_t *curve = uECC_secp256r1();
+    int i, errorc = 0;
+
+    int curve_size = uECC_curve_private_key_size(curve);
+    int public_key_size = uECC_curve_public_key_size(curve);
+
+    uint8_t l_secret1[curve_size];
+    uint8_t l_secret2[curve_size];
+
+    /* reserve space for a SHA-256 hash */
+    uint8_t l_hash[32] = { 0 };
+
+    uint8_t l_sig[public_key_size];
+
+    printf("Testing %d random private key pairs and signature using HWRNG\n", TESTROUNDS);
+
+    /* initialize hardware random number generator */
+    hwrng_init();
+
+    uint8_t l_private1[curve_size];
+    uint8_t l_private2[curve_size];
+
+    uint8_t l_public1[public_key_size];
+    uint8_t l_public2[public_key_size];
+
+    for (i = 0; i < TESTROUNDS; ++i) {
+        printf(".");
+
+        if (!uECC_make_key(l_public1, l_private1, curve) || !uECC_make_key(l_public2, l_private2, curve)) {
+            printf("\nRound %d: uECC_make_key() failed", i);
+            errorc++;
+        }
+        else {
+            if (!uECC_shared_secret(l_public2, l_private1, l_secret1, curve)) {
+                printf("\nRound %d: shared_secret() failed (1)", i);
+                errorc++;
+            }
+            else {
+                if (!uECC_shared_secret(l_public1, l_private2, l_secret2, curve)) {
+                    printf("\nRound: %d: shared_secret() failed (2)", i);
+                    errorc++;
+                }
+                else {
+                    if (memcmp(l_secret1, l_secret2, sizeof(l_secret1)) != 0) {
+                        printf("\nShared secrets are not identical!\n");
+                        errorc++;
+                    }
+
+                    /* copy some bogus data into the hash */
+                    memcpy(l_hash, l_public1, 32);
+
+                    if ((uECC_sign(l_private1, l_hash, sizeof(l_hash), l_sig, curve)) != 1) {
+                        printf("\nRound %d: uECC_sign() failed", i);
+                        errorc++;
+                    }
+                    else {
+                        if ((uECC_verify(l_public1, l_hash, sizeof(l_hash), l_sig, curve)) != 1) {
+                            printf("\nRound %d: uECC_verify() failed", i);
+                            errorc++;
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    printf(" done with %d error(s)\n", errorc);
+
+    if (errorc == 0) {
+        return 0;
+    }
+    else {
+        return 1;
+    }
+}

tests/pkg_micro-ecc/Makefile

@@ -1,6 +1,7 @@
 APPLICATION = pkg_micro-ecc
 include ../Makefile.tests_common
 
+USEMODULE += hashes
 USEPKG += micro-ecc
 
 include $(RIOTBASE)/Makefile.include

tests/pkg_micro-ecc/main.c

@@ -36,11 +36,36 @@
 
 #include <stdio.h>
 #include <string.h>
+#include "hashes/sha256.h"
 #include "uECC.h"
-#include "periph/hwrng.h"
 
 #define TESTROUNDS  16
 
+typedef struct uECC_SHA256_HashContext {
+    uECC_HashContext uECC;
+    sha256_context_t ctx;
+} uECC_SHA256_HashContext;
+
+static void _init_sha256(const uECC_HashContext *base)
+{
+    uECC_SHA256_HashContext *context = (uECC_SHA256_HashContext*)base;
+    sha256_init(&context->ctx);
+}
+
+static void _update_sha256(const uECC_HashContext *base,
+                          const uint8_t *message,
+                          unsigned message_size)
+{
+    uECC_SHA256_HashContext *context = (uECC_SHA256_HashContext*)base;
+    sha256_update(&context->ctx, message, message_size);
+}
+
+static void _finish_sha256(const uECC_HashContext *base, uint8_t *hash_result)
+{
+    uECC_SHA256_HashContext *context = (uECC_SHA256_HashContext*)base;
+    sha256_final(&context->ctx, hash_result);
+}
+
 int main(void)
 {
     printf("micro-ecc compiled!\n");
@@ -50,11 +75,6 @@ int main(void)
 
     int curve_size = uECC_curve_private_key_size(curve);
     int public_key_size = uECC_curve_public_key_size(curve);
-    uint8_t l_private1[curve_size];
-    uint8_t l_private2[curve_size];
-
-    uint8_t l_public1[public_key_size];
-    uint8_t l_public2[public_key_size];
 
     uint8_t l_secret1[curve_size];
     uint8_t l_secret2[curve_size];
@@ -64,47 +84,79 @@ int main(void)
 
     uint8_t l_sig[public_key_size];
 
-    /* initialize hardware random number generator */
-    hwrng_init();
+    printf("Testing %d random private key pairs and signature without using HWRNG\n", TESTROUNDS);
 
-    printf("Testing %d random private key pairs and signature\n", TESTROUNDS);
+    /* use pre-generated keys for no-HWRNG platforms */
+    uint8_t l_private1[] = {
+        0x9b, 0x4c, 0x4b, 0xa0, 0xb7, 0xb1, 0x25, 0x23,
+        0x9c, 0x09, 0x85, 0x4f, 0x9a, 0x21, 0xb4, 0x14,
+        0x70, 0xe0, 0xce, 0x21, 0x25, 0x00, 0xa5, 0x62,
+        0x34, 0xa4, 0x25, 0xf0, 0x0f, 0x00, 0xeb, 0xe7,
+    };
+    uint8_t l_public1[] = {
+        0x54, 0x3e, 0x98, 0xf8, 0x14, 0x55, 0x08, 0x13,
+        0xb5, 0x1a, 0x1d, 0x02, 0x02, 0xd7, 0x0e, 0xab,
+        0xa0, 0x98, 0x74, 0x61, 0x91, 0x12, 0x3d, 0x96,
+        0x50, 0xfa, 0xd5, 0x94, 0xa2, 0x86, 0xa8, 0xb0,
+        0xd0, 0x7b, 0xda, 0x36, 0xba, 0x8e, 0xd3, 0x9a,
+        0xa0, 0x16, 0x11, 0x0e, 0x1b, 0x6e, 0x81, 0x13,
+        0xd7, 0xf4, 0x23, 0xa1, 0xb2, 0x9b, 0xaf, 0xf6,
+        0x6b, 0xc4, 0x2a, 0xdf, 0xbd, 0xe4, 0x61, 0x5c,
+    };
+    uint8_t l_private2[] = {
+        0xb5, 0x45, 0xaf, 0xa0, 0x2e, 0x5c, 0xa6, 0x17,
+        0x3b, 0x5a, 0x55, 0x76, 0x67, 0x5d, 0xd4, 0x5e,
+        0x41, 0x7c, 0x4f, 0x19, 0x9f, 0xb9, 0x75, 0xdc,
+        0xba, 0x57, 0xc4, 0xa2, 0x26, 0xc6, 0x86, 0x2a,
+    };
+    uint8_t l_public2[] = {
+        0x2e, 0x81, 0x24, 0x3c, 0x44, 0xac, 0x63, 0x13,
+        0x9b, 0xc1, 0x27, 0xe9, 0x53, 0x3b, 0x0a, 0xe2,
+        0xf9, 0x22, 0xcd, 0x06, 0xfd, 0x12, 0x17, 0x2e,
+        0xe5, 0x0e, 0xb5, 0xce, 0x6b, 0x50, 0xe2, 0x44,
+        0xbf, 0x6b, 0x3f, 0xe8, 0x4e, 0x70, 0xd1, 0x06,
+        0x85, 0x84, 0xb8, 0xef, 0xe2, 0x25, 0x91, 0x21,
+        0xf3, 0x46, 0x70, 0xa9, 0x1c, 0x79, 0x19, 0xe3,
+        0xfb, 0x11, 0x36, 0x64, 0x37, 0x64, 0x58, 0xc9,
+    };
+    uint8_t tmp[2 * SHA256_DIGEST_LENGTH + SHA256_INTERNAL_BLOCK_SIZE];
 
     for (i = 0; i < TESTROUNDS; ++i) {
         printf(".");
 
-        if (!uECC_make_key(l_public1, l_private1, curve) || !uECC_make_key(l_public2, l_private2, curve)) {
-            printf("\nRound %d: uECC_make_key() failed", i);
+        if (!uECC_shared_secret(l_public2, l_private1, l_secret1, curve)) {
+            printf("\nRound %d: shared_secret() failed (1)", i);
             errorc++;
-        }
-        else {
-            if (!uECC_shared_secret(l_public2, l_private1, l_secret1, curve)) {
-                printf("\nRound %d: shared_secret() failed (1)", i);
+        } else {
+            if (!uECC_shared_secret(l_public1, l_private2, l_secret2, curve)) {
+                printf("\nRound: %d: shared_secret() failed (2)", i);
                 errorc++;
-            }
-            else {
-                if (!uECC_shared_secret(l_public1, l_private2, l_secret2, curve)) {
-                    printf("\nRound: %d: shared_secret() failed (2)", i);
+            } else {
+                if (memcmp(l_secret1, l_secret2, sizeof(l_secret1)) != 0) {
+                    printf("\nShared secrets are not identical!\n");
                     errorc++;
                 }
-                else {
-                    if (memcmp(l_secret1, l_secret2, sizeof(l_secret1)) != 0) {
-                        printf("\nShared secrets are not identical!\n");
-                        errorc++;
-                    }
 
-                    /* copy some bogus data into the hash */
-                    memcpy(l_hash, l_public1, 32);
+                /* copy some bogus data into the hash */
+                memcpy(l_hash, l_public1, 32);
 
-                    if ((uECC_sign(l_private1, l_hash, sizeof(l_hash), l_sig, curve)) != 1) {
-                        printf("\nRound %d: uECC_sign() failed", i);
+                uECC_SHA256_HashContext ctx;
+                ctx.uECC.init_hash = &_init_sha256;
+                ctx.uECC.update_hash = &_update_sha256;
+                ctx.uECC.finish_hash = &_finish_sha256;
+                ctx.uECC.block_size = 64;
+                ctx.uECC.result_size = 32;
+                ctx.uECC.tmp = tmp;
+                if (uECC_sign_deterministic(l_private1, l_hash, sizeof(l_hash),
+                                            &ctx.uECC, l_sig, curve) != 1) {
+                    printf("\nRound %d: uECC_sign_deterministic() failed", i);
+                    errorc++;
+                } else {
+                    if (uECC_verify(l_public1, l_hash, sizeof(l_hash), l_sig,
+                                    curve) != 1) {
+                        printf("\nRound %d: uECC_verify() failed", i);
                         errorc++;
                     }
-                    else {
-                        if ((uECC_verify(l_public1, l_hash, sizeof(l_hash), l_sig, curve)) != 1) {
-                            printf("\nRound %d: uECC_verify() failed", i);
-                            errorc++;
-                        }
-                    }
                 }
             }
         }