From 4f732c9b6bb85a35ce895328bfce901ebf82a00f Mon Sep 17 00:00:00 2001 From: David Garske Date: Thu, 16 Apr 2020 14:17:22 -0700 Subject: [PATCH 1/3] Improved ECC sign/verify examples using raw key/signature elements. Add ECC public key export example. Cleanup ecc_keys.c example. --- .gitignore | 3 + ecc/ecc-sign.c | 8 +- pk/ecc/Makefile | 9 +- pk/ecc/README | 8 - pk/ecc/README.md | 27 ++++ pk/ecc/ecc_keys.c | 69 +++++---- pk/ecc/ecc_pub.c | 107 ++++++++++++++ pk/ecc/ecc_sign.c | 350 ++++++++++++++++++++++++++++++++++++++++++++ pk/ecc/ecc_verify.c | 245 +++++++++++++++++++++++++++++++ 9 files changed, 786 insertions(+), 40 deletions(-) delete mode 100644 pk/ecc/README create mode 100644 pk/ecc/README.md create mode 100644 pk/ecc/ecc_pub.c create mode 100644 pk/ecc/ecc_sign.c create mode 100644 pk/ecc/ecc_verify.c diff --git a/.gitignore b/.gitignore index 91a39b1e..1002011c 100644 --- a/.gitignore +++ b/.gitignore @@ -170,6 +170,9 @@ pk/rsa-pss/rsa-pss pk/rsa-pss/rsa-public.der pk/rsa-pss/sign.txt pk/rsa/rsa-nb +pk/ecc/ecc_verify +pk/ecc/ecc_sign +pk/ecc/ecc_pub pk/ecc/ecc_keys #Example der and x963 files pk/ecc/*.der diff --git a/ecc/ecc-sign.c b/ecc/ecc-sign.c index 997af4de..f217cd0a 100644 --- a/ecc/ecc-sign.c +++ b/ecc/ecc-sign.c @@ -78,7 +78,7 @@ static void PrintBuffer(const byte* buffer, word32 length) static int HashFirmware(byte* hashBuf) { int ret; - Sha256 sha; + wc_Sha256 sha; int idx = 0, len = gFwLen, sz; ret = wc_InitSha256(&sha); @@ -151,8 +151,8 @@ static int SignFirmware(byte* hashBuf, word32 hashLen, byte* sigBuf, word32* sig int main(void) { int ret; - byte hashBuf[SHA256_DIGEST_SIZE]; - word32 hashLen = SHA256_DIGEST_SIZE; + byte hashBuf[WC_SHA256_DIGEST_SIZE]; + word32 hashLen = WC_SHA256_DIGEST_SIZE; byte sigBuf[ECC_MAX_SIG_SIZE]; word32 sigLen = ECC_MAX_SIG_SIZE; int i; @@ -162,7 +162,7 @@ int main(void) gFwBuf[i] = (byte)i; } - /* try perofrming signature a few times */ + /* try performing signature a few times */ for (i=0; i < gSignTimes; i++) { memset(hashBuf, 0, hashLen); ret = HashFirmware(hashBuf); diff --git a/pk/ecc/Makefile b/pk/ecc/Makefile index 6bf63fd4..c72703d5 100644 --- a/pk/ecc/Makefile +++ b/pk/ecc/Makefile @@ -2,10 +2,15 @@ CC=gcc CFLAGS=-Wall LIBS= -lwolfssl -ecc_keys: ecc_keys.o +SRC=$(wildcard *.c) +TARGETS=$(patsubst %.c, %, $(SRC)) + +all: $(TARGETS) + +%: %.c $(CC) -o $@ $^ $(CFLAGS) $(LIBS) .PHONY: clean clean: - rm -f *.der *.x963 *.o ecc_keys + rm -f $(TARGETS) *.der *.x963 diff --git a/pk/ecc/README b/pk/ecc/README deleted file mode 100644 index 70a864e7..00000000 --- a/pk/ecc/README +++ /dev/null @@ -1,8 +0,0 @@ -Shows examples of how to work with storing and loading keys after they have been generated. ecc_keys.c creates a key structure than stores the private key in DER formate. After storing the private key it then loads it back into a ecc_key struct. ecc_keys.c also shows how to export and import public keys. - -The build option used for wolfSSL is - -``` -./configure --enable-keygen --enable-ecc -``` - diff --git a/pk/ecc/README.md b/pk/ecc/README.md new file mode 100644 index 00000000..d400a978 --- /dev/null +++ b/pk/ecc/README.md @@ -0,0 +1,27 @@ +# Asymmetric ECC Examples + +The build option used for wolfSSL are: + +``` +./configure --enable-ecc CFLAGS="-DWOLFSSL_PUBLIC_MP" +make +sudo make install +sudo ldconfig +``` + + +## ecc_keys + +The `ecc_keys.c` example shows how to work with storing and loading keys after they have been generated. + +1. Creates a key structure +2. Stores the private key in DER format. +3. Loads DER private key back into a ecc_key struct. + +## ecc_sign + +The `ecc_verify.c` example uses NIST test vectors to demonstrate hashing a message and verifying an ECC signature. + +## ecc_verify + +The `ecc_sign.c:` example takes a random message and private key, creates a signature then verifies it. diff --git a/pk/ecc/ecc_keys.c b/pk/ecc/ecc_keys.c index 468076e7..849d8b04 100644 --- a/pk/ecc/ecc_keys.c +++ b/pk/ecc/ecc_keys.c @@ -19,47 +19,63 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */ +/* +./configure && make && sudo make install +gcc -lwolfssl -o ecc_pub ecc_pub.c +*/ -#include +#ifndef WOLFSSL_USER_SETTINGS + #include +#endif +#include +#include #include #include -#include #include #include +#define ECC_CURVE_SZ 32 /* SECP256R1 curve size in bytes */ +#define ECC_CURVE_ID ECC_SECP256R1 + +#define MAX_DER_SZ 256 + int main() { + int ret; ecc_key key; - byte der[4096]; - byte buf[4096]; - word32 idx = 0; + WC_RNG rng; + byte der[MAX_DER_SZ]; + byte buf[MAX_DER_SZ]; + word32 idx; FILE* derFile; size_t sz; - RNG rng; - wc_InitRng(&rng); wc_ecc_init(&key); - if (wc_ecc_make_key(&rng, 32, &key) != 0) { - printf("error making ecc key\n"); - return -1; + ret = wc_ecc_make_key_ex(&rng, ECC_CURVE_SZ, &key, ECC_CURVE_ID); + if (ret != 0) { + printf("error %d making ecc key\n", ret); + return ret; } /* write private key */ - if (wc_EccKeyToDer(&key, der, sizeof(der)) < 0) { - printf("error in ecc to der\n"); - return -1; + ret = wc_EccKeyToDer(&key, der, sizeof(der)); + if (ret < 0) { + printf("error %d in ecc to der\n", ret); + return ret; } - printf("writing private key to ecc-key.der\n"); + sz = ret; + + printf("writing private key to ecc-key.der (%d bytes)\n", (int)sz); derFile = fopen("ecc-key.der", "w"); if (!derFile) { printf("error loading file\n"); return -1; } - sz = fwrite(der, 1, 4096, derFile); + fwrite(der, 1, sz, derFile); fclose(derFile); wc_ecc_free(&key); @@ -70,13 +86,13 @@ int main() printf("error reading from file\n"); return -1; } - - sz = fread(buf, 1, 4096, derFile); + sz = fread(buf, 1, sizeof(buf), derFile); fclose(derFile); /* load private ecc key */ - printf("storing private key in ecc struct\n"); + printf("loading private key in ecc struct\n"); wc_ecc_init(&key); + idx = 0; if (wc_EccPrivateKeyDecode(buf, &idx, &key, (word32)sz) != 0) { printf("error decoding private key\n"); return -1; @@ -94,25 +110,27 @@ int main() /* to store a public key */ wc_ecc_init(&key); - if (wc_ecc_make_key(&rng, 32, &key) != 0) { - printf("error making ecc key\n"); - return -1; + ret = wc_ecc_make_key_ex(&rng, ECC_CURVE_SZ, &key, ECC_CURVE_ID); + if (ret != 0) { + printf("error %d making ecc key\n", ret); + return ret; } - printf("storing public key into ecc-public.x963\n"); + printf("exporting public key\n"); memset(buf, 0, sizeof(buf)); - idx = sizeof(buf); - if (wc_ecc_export_x963(&key, buf, &idx) != 0) { + sz = sizeof(buf); + if (wc_ecc_export_x963(&key, buf, (word32*)&sz) != 0) { printf("error exporting public ecc key\n"); return -1; } + printf("storing public key into ecc-public.x963 (%d bytes)\n", (int)sz); derFile = fopen("ecc-public.x963", "w"); /* reused the derFile pointer */ if (!derFile) { printf("error loading file\n"); return -1; } - sz = fwrite(buf, 1, idx, derFile); + fwrite(buf, 1, sz, derFile); /* close stuff up */ fclose(derFile); @@ -120,4 +138,3 @@ int main() wc_FreeRng(&rng); return 0; } - diff --git a/pk/ecc/ecc_pub.c b/pk/ecc/ecc_pub.c new file mode 100644 index 00000000..29518fdf --- /dev/null +++ b/pk/ecc/ecc_pub.c @@ -0,0 +1,107 @@ +/* ecc_pub.c + * + * Copyright (C) 2006-2020 wolfSSL Inc. + * + * This file is part of wolfSSL. (formerly known as CyaSSL) + * + * wolfSSL is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * wolfSSL is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA + */ + +/* example code for extracting public from private */ +/* +./configure && make && sudo make install +gcc -lwolfssl -o ecc_pub ecc_pub.c +*/ + +#ifndef WOLFSSL_USER_SETTINGS + #include +#endif +#include +#include +#include + +#include +#include + +#define ECC_CURVE_SZ 32 /* SECP256R1 curve size in bytes */ +#define ECC_CURVE_ID ECC_SECP256R1 + +/* Private key "d" only */ +static const uint8_t kPrivKey[] = { + /* d */ + 0x1e, 0xe7, 0x70, 0x07, 0xd3, 0x30, 0x94, 0x39, + 0x28, 0x90, 0xdf, 0x23, 0x88, 0x2c, 0x4a, 0x34, + 0x15, 0xdb, 0x4c, 0x43, 0xcd, 0xfa, 0xe5, 0x1f, + 0x3d, 0x4c, 0x37, 0xfe, 0x59, 0x3b, 0x96, 0xd8 +}; + +static void print_hex(uint8_t* data, int sz) +{ + int i; + for (i = 0; i < sz; i++) { + printf("%02X ", data[i]); + if (i > 0 && ((i+1) % 16) == 0) + printf("\n"); + } + printf("\n"); +} + +int main() +{ +#if defined(HAVE_ECC) && defined(HAVE_ECC_KEY_EXPORT) + int ret; + ecc_key ecc; + uint8_t pubKey[ECC_CURVE_SZ*2]; + uint32_t pubQxSz = ECC_CURVE_SZ, pubQySz = ECC_CURVE_SZ; + + /* Setup the ECC key */ + ret = wc_ecc_init(&ecc); + if (ret < 0) { + return ret; + } + + memset(pubKey, 0, sizeof(pubKey)); + + /* Import private key "k" */ + ret = wc_ecc_import_private_key_ex( + kPrivKey, sizeof(kPrivKey), /* private key "d" */ + NULL, 0, /* public (optional) */ + &ecc, + ECC_CURVE_ID + ); + + /* Export public key */ + if (ret == 0) { + ret = wc_ecc_make_pub(&ecc, NULL); + } + if (ret == 0) { + ret = wc_ecc_export_public_raw(&ecc, + pubKey, &pubQxSz, /* public Qx */ + pubKey+ECC_CURVE_SZ, &pubQySz /* public Qy */ + ); + } + + printf("Public Key Qx: %d\n", pubQxSz); + print_hex(pubKey, ECC_CURVE_SZ); + printf("Public Key Qy: %d\n", pubQySz); + print_hex(pubKey+ECC_CURVE_SZ, ECC_CURVE_SZ); + + wc_ecc_free(&ecc); + return ret; +#else + printf("wolfSSL needs to be built with ECC and key export enabled\n"); + return -1; +#endif /* HAVE_ECC && HAVE_ECC_KEY_EXPORT */ +} \ No newline at end of file diff --git a/pk/ecc/ecc_sign.c b/pk/ecc/ecc_sign.c new file mode 100644 index 00000000..cd131e0c --- /dev/null +++ b/pk/ecc/ecc_sign.c @@ -0,0 +1,350 @@ +/* ecc_sign.c + * + * Copyright (C) 2006-2020 wolfSSL Inc. + * + * This file is part of wolfSSL. (formerly known as CyaSSL) + * + * wolfSSL is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * wolfSSL is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA + */ + +/* Example to demonstrate SHA-256 hashing and ECC Sign */ +/* +./configure CFLAGS="-DWOLFSSL_PUBLIC_MP" && make && sudo make install +gcc -lwolfssl -o ecc_sign ecc_sign.c +*/ + +#ifndef WOLFSSL_USER_SETTINGS + #include +#endif +#include +#include +#include +#include +#include +#include + +#include +#include + +#define ECC_CURVE_SZ 32 /* SECP256R1 curve size in bytes */ +#define ECC_CURVE_ID ECC_SECP256R1 + + +/* Test Vector */ +/* NIST P-256, SHA256 ECC Test Vector */ +static const uint8_t kMsg[] = { + 0x69, 0xbc, 0x9f, 0xce, 0x68, 0x17, 0xc2, 0x10, 0xea, 0xfc, 0x10, 0x65, 0x67, 0x52, 0xed, 0x78, + 0x6e, 0xb8, 0x83, 0x9c, 0x9a, 0xb4, 0x56, 0x0d, 0xc1, 0x0d, 0x1f, 0x78, 0x6e, 0x75, 0xd7, 0xbe, + 0x92, 0x6b, 0x12, 0xf6, 0x76, 0x60, 0x8e, 0xb1, 0xf4, 0x19, 0x0c, 0x81, 0xe7, 0x54, 0x5e, 0xbc, + 0xe0, 0xae, 0xc2, 0x7d, 0x1b, 0xc4, 0x6e, 0xec, 0xb1, 0x99, 0x6c, 0xbf, 0x0e, 0x38, 0xa8, 0x01, + 0xa6, 0x9a, 0x48, 0x12, 0xe4, 0xc9, 0x3b, 0xf0, 0x63, 0x46, 0x15, 0xb4, 0x61, 0xa8, 0x1a, 0x60, + 0x71, 0x87, 0x98, 0xd7, 0x6f, 0x98, 0x7b, 0x2d, 0xb9, 0x19, 0x1b, 0x21, 0x9c, 0x70, 0x58, 0xe8, + 0x0d, 0x0f, 0xe9, 0x2d, 0x9a, 0x9a, 0xf1, 0x55, 0xa0, 0x4c, 0xd3, 0x07, 0xbd, 0x97, 0x48, 0xec, + 0x88, 0x0a, 0xaf, 0xb3, 0x80, 0x78, 0xa4, 0x59, 0x43, 0x57, 0xd3, 0xa7, 0x01, 0x66, 0x0e, 0xfc +}; +static const uint8_t kPrivKey[] = { + /* d */ + 0x1e, 0xe7, 0x70, 0x07, 0xd3, 0x30, 0x94, 0x39, + 0x28, 0x90, 0xdf, 0x23, 0x88, 0x2c, 0x4a, 0x34, + 0x15, 0xdb, 0x4c, 0x43, 0xcd, 0xfa, 0xe5, 0x1f, + 0x3d, 0x4c, 0x37, 0xfe, 0x59, 0x3b, 0x96, 0xd8 +}; +static const uint8_t kPubKey[] = { + /* Qx */ + 0x96, 0x93, 0x1c, 0x53, 0x0b, 0x43, 0x6c, 0x42, + 0x0c, 0x52, 0x90, 0xe4, 0xa7, 0xec, 0x98, 0xb1, + 0xaf, 0xd4, 0x14, 0x49, 0xd8, 0xc1, 0x42, 0x82, + 0x04, 0x78, 0xd1, 0x90, 0xae, 0xa0, 0x6c, 0x07, + /* Qy */ + 0xf2, 0x3a, 0xb5, 0x10, 0x32, 0x8d, 0xce, 0x9e, + 0x76, 0xa0, 0xd2, 0x8c, 0xf3, 0xfc, 0xa9, 0x94, + 0x43, 0x24, 0xe6, 0x82, 0x00, 0x40, 0xc6, 0xdb, + 0x1c, 0x2f, 0xcd, 0x38, 0x4b, 0x60, 0xdd, 0x61 +}; + + +#ifndef NO_SHA256 +/* perform hashing block by block */ +int crypto_sha256(const uint8_t *buf, uint32_t len, uint8_t *hash, + uint32_t hashSz, uint32_t blkSz) +{ + int ret; + uint32_t i = 0, chunk; + wc_Sha256 sha256; + + /* validate arguments */ + if ((buf == NULL && len > 0) || hash == NULL || + hashSz < WC_SHA256_DIGEST_SIZE || blkSz == 0) + { + return BAD_FUNC_ARG; + } + + /* Init Sha256 structure */ + ret = wc_InitSha256(&sha256); + if (ret != 0) { + return ret; + } + while (i < len) { + chunk = blkSz; + if ((chunk + i) > len) + chunk = len - i; + /* Perform chunked update */ + ret = wc_Sha256Update(&sha256, (buf + i), chunk); + if (ret != 0) { + break; + } + i += chunk; + } + if (ret == 0) { + /* Get final digest result */ + ret = wc_Sha256Final(&sha256, hash); + } + return ret; +} +#endif + +#ifdef HAVE_ECC +#ifdef HAVE_ECC_VERIFY +/* perform verify of signature and hash using public key */ +/* key is public Qx + public Qy */ +/* sig is r + s */ +int crypto_ecc_verify(const uint8_t *key, uint32_t keySz, + const uint8_t *hash, uint32_t hashSz, const uint8_t *sig, uint32_t sigSz, + int curveSz, int curveId) +{ + int ret, verify_res = 0; + mp_int r, s; + ecc_key ecc; + + /* validate arguments */ + if (key == NULL || hash == NULL || sig == NULL || curveSz == 0 || + hashSz == 0 || keySz < (curveSz*2) || sigSz < (curveSz*2)) + { + return BAD_FUNC_ARG; + } + + /* Setup the ECC key */ + ret = wc_ecc_init(&ecc); + if (ret < 0) { + return ret; + } + + /* Setup the signature r/s variables */ + ret = mp_init(&r); + if (ret != MP_OKAY) { + wc_ecc_free(&ecc); + return ret; + } + ret = mp_init(&s); + if (ret != MP_OKAY) { + mp_clear(&r); + wc_ecc_free(&ecc); + return ret; + } + + /* Import public key x/y */ + ret = wc_ecc_import_unsigned( + &ecc, + (byte*)key, /* Public "x" Coordinate */ + (byte*)(key + curveSz), /* Public "y" Coordinate */ + NULL, /* Private "d" (optional) */ + curveId /* ECC Curve Id */ + ); + /* Make sure it was a public key imported */ + if (ret == 0 && ecc.type != ECC_PUBLICKEY) { + ret = ECC_BAD_ARG_E; + } + + /* Import signature r/s */ + if (ret == 0) { + ret = mp_read_unsigned_bin(&r, sig, curveSz); + } + if (ret == 0) { + ret = mp_read_unsigned_bin(&s, sig + curveSz, curveSz); + } + + /* Verify ECC Signature */ + if (ret == 0) { + ret = wc_ecc_verify_hash_ex( + &r, &s, /* r/s as mp_int */ + hash, hashSz, /* computed hash digest */ + &verify_res, /* verification result 1=success */ + &ecc + ); + } + + /* check verify result */ + if (ret == 0 && verify_res == 0) { + ret = SIG_VERIFY_E; + } + + mp_clear(&r); + mp_clear(&s); + wc_ecc_free(&ecc); + + return ret; +} +#endif /* HAVE_ECC_VERIFY */ + +#ifdef HAVE_ECC_SIGN +/* perform signature operation against hash using private key */ +int crypto_ecc_sign(const uint8_t *key, uint32_t keySz, + const uint8_t *hash, uint32_t hashSz, uint8_t *sig, uint32_t* sigSz, + int curveSz, int curveId) +{ + int ret; + mp_int r, s; + ecc_key ecc; + WC_RNG rng; + + /* validate arguments */ + if (key == NULL || hash == NULL || sig == NULL || sigSz == NULL || + curveSz == 0 || hashSz == 0 || keySz < curveSz || *sigSz < (curveSz*2)) + { + return BAD_FUNC_ARG; + } + + /* Initialize signature result */ + memset(sig, 0, curveSz*2); + + /* Setup the RNG */ + ret = wc_InitRng(&rng); + if (ret < 0) { + return ret; + } + + /* Setup the ECC key */ + ret = wc_ecc_init(&ecc); + if (ret < 0) { + wc_FreeRng(&rng); + return ret; + } + + /* Setup the signature r/s variables */ + ret = mp_init(&r); + if (ret != MP_OKAY) { + wc_ecc_free(&ecc); + wc_FreeRng(&rng); + return ret; + } + ret = mp_init(&s); + if (ret != MP_OKAY) { + mp_clear(&r); + wc_ecc_free(&ecc); + wc_FreeRng(&rng); + return ret; + } + + /* Import private key "k" */ + ret = wc_ecc_import_private_key_ex( + key, keySz, /* private key "d" */ + NULL, 0, /* public (optional) */ + &ecc, + curveId /* ECC Curve Id */ + ); + if (ret == 0) { + /* Verify ECC Signature */ + ret = wc_ecc_sign_hash_ex( + hash, hashSz, /* computed hash digest */ + &rng, &ecc, /* random and key context */ + &r, &s /* r/s as mp_int */ + ); + + /* export r/s */ + mp_to_unsigned_bin(&r, sig); + mp_to_unsigned_bin(&s, sig + curveSz); + } + + mp_clear(&r); + mp_clear(&s); + wc_ecc_free(&ecc); + wc_FreeRng(&rng); + + return ret; +} +#endif /* HAVE_ECC_SIGN */ +#endif /* HAVE_ECC */ + +static void print_hex(uint8_t* data, int sz) +{ + int i; + for (i = 0; i < sz; i++) { + printf("%02X ", data[i]); + if (i > 0 && ((i+1) % 16) == 0) + printf("\n"); + } + printf("\n"); +} + +int main() +{ +#if defined(HAVE_ECC) && defined(HAVE_ECC_SIGN) && defined(HAVE_ECC_VERIFY) && \ + !defined(NO_SHA256) + int ret; + uint8_t hash[WC_SHA256_DIGEST_SIZE]; + uint8_t sig[ECC_CURVE_SZ*2]; + uint32_t sigSz = sizeof(sig); + +#ifdef DEBUG_WOLFSSL + wolfSSL_Debugging_ON(); +#endif + + printf("Running NIST P-256,SHA-256 Sign Test\n"); + + ret = crypto_sha256( + kMsg, sizeof(kMsg), /* input message */ + hash, sizeof(hash), /* hash digest result */ + 32 /* configurable block / chunk size */ + ); + if (ret == 0) { + /* Sign hash using private key */ + /* Note: result of an ECC sign varies for each call even with same + private key and hash. This is because a new random public key is + used for each operation. */ + ret = crypto_ecc_sign( + kPrivKey, sizeof(kPrivKey), /* private key */ + hash, sizeof(hash), /* computed hash digest */ + sig, &sigSz, /* signature r/s */ + ECC_CURVE_SZ, /* SECP256R1 curve size in bytes */ + ECC_CURVE_ID /* curve id */ + ); + } + + if (ret == 0) { + /* Verify generated signature is valid */ + ret = crypto_ecc_verify( + kPubKey, sizeof(kPubKey), /* public key point x/y */ + hash, sizeof(hash), /* computed hash digest */ + sig, sigSz, /* signature r/s */ + ECC_CURVE_SZ, /* curve size in bytes */ + ECC_CURVE_ID /* curve id */ + ); + } + + printf("Signature %d\n", sigSz); + print_hex(sig, sigSz); + + if (ret != 0) { + printf("Failure %d: %s\n", ret, wc_GetErrorString(ret)); + return -1; + } + printf("Success\n"); + + return 0; +#else + printf("wolfSSL requires ECC and SHA256\n"); + return -1; +#endif +} diff --git a/pk/ecc/ecc_verify.c b/pk/ecc/ecc_verify.c new file mode 100644 index 00000000..236b2076 --- /dev/null +++ b/pk/ecc/ecc_verify.c @@ -0,0 +1,245 @@ +/* ecc_verify.c + * + * Copyright (C) 2006-2020 wolfSSL Inc. + * + * This file is part of wolfSSL. (formerly known as CyaSSL) + * + * wolfSSL is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * wolfSSL is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA + */ + +/* Example to demonstrate SHA-256 hashing and ECC Verify */ +/* +./configure CFLAGS="-DWOLFSSL_PUBLIC_MP" && make && sudo make install +gcc -lwolfssl -o ecc_verify ecc_verify.c +*/ + +#ifndef WOLFSSL_USER_SETTINGS + #include +#endif +#include +#include +#include +#include +#include +#include + +#include +#include + +#define ECC_CURVE_SZ 32 /* SECP256R1 curve size in bytes */ +#define ECC_CURVE_ID ECC_SECP256R1 + +/* Test Vectors */ +/* NIST P-256, SHA256 ECC Test Vector */ +static const uint8_t kMsg[] = { + 0xba, 0xc1, 0x87, 0x53, 0x80, 0x9b, 0x27, 0xad, 0xa2, 0xb9, 0x4f, 0xd6, 0xac, 0x75, 0x39, 0xee, + 0x12, 0x95, 0xe2, 0xec, 0xf3, 0x80, 0x25, 0x8e, 0x89, 0x42, 0xb6, 0xf0, 0xeb, 0xbc, 0xe1, 0xaa, + 0xc9, 0x80, 0xfb, 0x0f, 0xe9, 0x36, 0xf9, 0x5d, 0xd1, 0x75, 0xc0, 0x27, 0x2d, 0x56, 0x07, 0x6a, + 0x50, 0xab, 0xd8, 0x26, 0x24, 0x8a, 0x6e, 0xab, 0xc9, 0xf1, 0x06, 0x6f, 0x65, 0x42, 0xe1, 0xdb, + 0xc7, 0x52, 0x1e, 0x3b, 0x0a, 0xfa, 0xc9, 0x74, 0x82, 0x39, 0x16, 0xfa, 0x2d, 0x8a, 0x23, 0x06, + 0x42, 0x97, 0x84, 0x8c, 0x3d, 0x93, 0x96, 0x84, 0x1d, 0xea, 0x53, 0x34, 0x3a, 0xf2, 0x5f, 0xbc, + 0xb1, 0x4d, 0x84, 0x85, 0xd5, 0x6c, 0xe3, 0x61, 0xce, 0x2a, 0x34, 0x47, 0x1c, 0x74, 0xeb, 0x7c, + 0x11, 0x20, 0x1d, 0x7f, 0x22, 0xc0, 0x9b, 0x8c, 0x90, 0xff, 0x32, 0x1a, 0xf0, 0xbd, 0xa0, 0xdc +}; +static const uint8_t kPubKey[] = { + /* Qx */ + 0x65, 0x6f, 0xfd, 0x63, 0x85, 0x88, 0x89, 0x35, + 0x68, 0xe4, 0xa2, 0xdc, 0x72, 0x10, 0xdb, 0xdd, + 0x4a, 0x9e, 0xef, 0x51, 0xfe, 0x04, 0xfb, 0xf8, + 0x7c, 0xbb, 0x1a, 0x0d, 0x6f, 0xdc, 0x89, 0xec, + /* Qy */ + 0x37, 0x1e, 0x4e, 0x7f, 0x82, 0x75, 0x14, 0xb9, + 0x17, 0x38, 0x40, 0xe3, 0x18, 0x34, 0xd4, 0x55, + 0xc1, 0x44, 0x10, 0x30, 0xad, 0x77, 0x8a, 0x46, + 0x2d, 0xc2, 0xff, 0x94, 0x98, 0xad, 0x1e, 0xd8 +}; +static const uint8_t kSigRS[] = { + /* R */ + 0x60, 0x7e, 0x20, 0xf0, 0x62, 0xa2, 0x9b, 0xa7, + 0xf0, 0x93, 0x34, 0xc1, 0x14, 0xd4, 0x9f, 0x79, + 0x4d, 0xb3, 0xf4, 0xf4, 0x6a, 0x79, 0xb0, 0x1a, + 0x0b, 0x39, 0x20, 0x4d, 0x2d, 0x1f, 0x04, 0x30, + /* S */ + 0x9e, 0xb5, 0x1b, 0xfe, 0xa4, 0x7c, 0x14, 0x0d, + 0xfd, 0x71, 0x5f, 0xfd, 0x52, 0x3b, 0xdb, 0xe7, + 0x70, 0xa2, 0xd6, 0x29, 0x40, 0x74, 0xa9, 0xaa, + 0x4f, 0x36, 0x46, 0xea, 0x06, 0x01, 0xe9, 0xcf +}; + + +#ifndef NO_SHA256 +/* perform hashing block by block */ +int crypto_sha256(const uint8_t *buf, uint32_t len, uint8_t *hash, + uint32_t hashSz, uint32_t blkSz) +{ + int ret; + uint32_t i = 0, chunk; + wc_Sha256 sha256; + + /* validate arguments */ + if ((buf == NULL && len > 0) || hash == NULL || + hashSz < WC_SHA256_DIGEST_SIZE || blkSz == 0) + { + return BAD_FUNC_ARG; + } + + /* Init Sha256 structure */ + ret = wc_InitSha256(&sha256); + if (ret != 0) { + return ret; + } + while (i < len) { + chunk = blkSz; + if ((chunk + i) > len) + chunk = len - i; + /* Perform chunked update */ + ret = wc_Sha256Update(&sha256, (buf + i), chunk); + if (ret != 0) { + break; + } + i += chunk; + } + if (ret == 0) { + /* Get final digest result */ + ret = wc_Sha256Final(&sha256, hash); + } + return ret; +} +#endif + + +#ifdef HAVE_ECC +#ifdef HAVE_ECC_VERIFY +/* perform verify of signature and hash using public key */ +/* key is public Qx + public Qy */ +/* sig is r + s */ +int crypto_ecc_verify(const uint8_t *key, uint32_t keySz, + const uint8_t *hash, uint32_t hashSz, const uint8_t *sig, uint32_t sigSz, + int curveSz, int curveId) +{ + int ret, verify_res = 0; + mp_int r, s; + ecc_key ecc; + + /* validate arguments */ + if (key == NULL || hash == NULL || sig == NULL || curveSz == 0 || + hashSz == 0 || keySz < (curveSz*2) || sigSz < (curveSz*2)) + { + return BAD_FUNC_ARG; + } + + /* Setup the ECC key */ + ret = wc_ecc_init(&ecc); + if (ret < 0) { + return ret; + } + + /* Setup the signature r/s variables */ + ret = mp_init(&r); + if (ret != MP_OKAY) { + wc_ecc_free(&ecc); + return ret; + } + ret = mp_init(&s); + if (ret != MP_OKAY) { + mp_clear(&r); + wc_ecc_free(&ecc); + return ret; + } + + /* Import public key x/y */ + ret = wc_ecc_import_unsigned( + &ecc, + (byte*)key, /* Public "x" Coordinate */ + (byte*)(key + curveSz), /* Public "y" Coordinate */ + NULL, /* Private "d" (optional) */ + curveId /* ECC Curve Id */ + ); + /* Make sure it was a public key imported */ + if (ret == 0 && ecc.type != ECC_PUBLICKEY) { + ret = ECC_BAD_ARG_E; + } + + /* Import signature r/s */ + if (ret == 0) { + ret = mp_read_unsigned_bin(&r, sig, curveSz); + } + if (ret == 0) { + ret = mp_read_unsigned_bin(&s, sig + curveSz, curveSz); + } + + /* Verify ECC Signature */ + if (ret == 0) { + ret = wc_ecc_verify_hash_ex( + &r, &s, /* r/s as mp_int */ + hash, hashSz, /* computed hash digest */ + &verify_res, /* verification result 1=success */ + &ecc + ); + } + + /* check verify result */ + if (ret == 0 && verify_res == 0) { + ret = SIG_VERIFY_E; + } + + mp_clear(&r); + mp_clear(&s); + wc_ecc_free(&ecc); + + return ret; +} +#endif /* HAVE_ECC_VERIFY */ +#endif /* HAVE_ECC */ + +int main() +{ +#if defined(HAVE_ECC) && defined(HAVE_ECC_VERIFY) && !defined(NO_SHA256) + int ret; + uint8_t hash[WC_SHA256_DIGEST_SIZE]; + +#ifdef DEBUG_WOLFSSL + wolfSSL_Debugging_ON(); +#endif + + printf("Running NIST P-256,SHA-256 Verify Test Vector\n"); + + ret = crypto_sha256( + kMsg, sizeof(kMsg), /* input message */ + hash, sizeof(hash), /* hash digest result */ + 32 /* configurable block / chunk size */ + ); + if (ret == 0) { + ret = crypto_ecc_verify( + kPubKey, sizeof(kPubKey), /* public key point x/y */ + hash, sizeof(hash), /* computed hash digest */ + kSigRS, sizeof(kSigRS), /* signature r/s */ + ECC_CURVE_SZ, /* curve size in bytes */ + ECC_CURVE_ID /* curve id */ + ); + } + + if (ret != 0) { + printf("Failure %d: %s\n", ret, wc_GetErrorString(ret)); + return -1; + } + printf("Success\n"); + + return ret; +#else + printf("wolfSSL requires ECC and SHA256\n"); + return -1; +#endif +} From 8b8915d17eedd42ec1c367cc106fd7cf42a5574e Mon Sep 17 00:00:00 2001 From: David Garske Date: Mon, 4 May 2020 07:58:43 -0700 Subject: [PATCH 2/3] Peer review feedback. Adjust README.md and fix possible use of un-init variable. --- pk/ecc/README.md | 8 ++++++-- pk/ecc/ecc_sign.c | 21 +++++++++++++-------- pk/ecc/ecc_verify.c | 10 ++++++---- 3 files changed, 25 insertions(+), 14 deletions(-) diff --git a/pk/ecc/README.md b/pk/ecc/README.md index d400a978..2f8b3771 100644 --- a/pk/ecc/README.md +++ b/pk/ecc/README.md @@ -20,8 +20,12 @@ The `ecc_keys.c` example shows how to work with storing and loading keys after t ## ecc_sign -The `ecc_verify.c` example uses NIST test vectors to demonstrate hashing a message and verifying an ECC signature. +The `ecc_sign.c:` example takes a random message and private key, creates a signature then verifies it. ## ecc_verify -The `ecc_sign.c:` example takes a random message and private key, creates a signature then verifies it. +The `ecc_verify.c` example uses NIST test vectors to demonstrate hashing a message and verifying an ECC signature. + +## ecc_pub + +The `ecc_pub` example code shows how to extracting an ECC public key from private key. diff --git a/pk/ecc/ecc_sign.c b/pk/ecc/ecc_sign.c index cd131e0c..fc602fe3 100644 --- a/pk/ecc/ecc_sign.c +++ b/pk/ecc/ecc_sign.c @@ -295,7 +295,7 @@ int main() int ret; uint8_t hash[WC_SHA256_DIGEST_SIZE]; uint8_t sig[ECC_CURVE_SZ*2]; - uint32_t sigSz = sizeof(sig); + uint32_t sigSz = 0; #ifdef DEBUG_WOLFSSL wolfSSL_Debugging_ON(); @@ -303,6 +303,8 @@ int main() printf("Running NIST P-256,SHA-256 Sign Test\n"); + memset(sig, 0, sizeof(sig)); + ret = crypto_sha256( kMsg, sizeof(kMsg), /* input message */ hash, sizeof(hash), /* hash digest result */ @@ -313,6 +315,7 @@ int main() /* Note: result of an ECC sign varies for each call even with same private key and hash. This is because a new random public key is used for each operation. */ + sigSz = sizeof(sig); ret = crypto_ecc_sign( kPrivKey, sizeof(kPrivKey), /* private key */ hash, sizeof(hash), /* computed hash digest */ @@ -333,16 +336,18 @@ int main() ); } - printf("Signature %d\n", sigSz); - print_hex(sig, sigSz); + if (ret == 0) { + printf("Signature %d\n", sigSz); + print_hex(sig, sigSz); - if (ret != 0) { - printf("Failure %d: %s\n", ret, wc_GetErrorString(ret)); - return -1; + printf("Success\n"); + } + else { + printf("Failure %d: %s\n", ret, wc_GetErrorString(ret)); + ret = -1; } - printf("Success\n"); - return 0; + return ret; #else printf("wolfSSL requires ECC and SHA256\n"); return -1; diff --git a/pk/ecc/ecc_verify.c b/pk/ecc/ecc_verify.c index 236b2076..3658b283 100644 --- a/pk/ecc/ecc_verify.c +++ b/pk/ecc/ecc_verify.c @@ -231,11 +231,13 @@ int main() ); } - if (ret != 0) { - printf("Failure %d: %s\n", ret, wc_GetErrorString(ret)); - return -1; + if (ret == 0) { + printf("Success\n"); + } + else { + printf("Failure %d: %s\n", ret, wc_GetErrorString(ret)); + ret = -1; } - printf("Success\n"); return ret; #else From 751d3ee4add467888c6728ebad190398aa24cc92 Mon Sep 17 00:00:00 2001 From: David Garske Date: Mon, 4 May 2020 08:00:11 -0700 Subject: [PATCH 3/3] Updated Makefile to allow for wolf path. --- pk/ecc/Makefile | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/pk/ecc/Makefile b/pk/ecc/Makefile index c72703d5..46501e57 100644 --- a/pk/ecc/Makefile +++ b/pk/ecc/Makefile @@ -1,6 +1,7 @@ CC=gcc -CFLAGS=-Wall -LIBS= -lwolfssl +WOLF_PATH=/usr/local +CFLAGS=-I$(WOLF_PATH)/include -Wall +LIBS=-L$(WOLF_PATH)/lib -lwolfssl SRC=$(wildcard *.c) TARGETS=$(patsubst %.c, %, $(SRC))