proxmark3/client/crypto/libpcrypto.c

422 lines
12 KiB
C

//-----------------------------------------------------------------------------
// Copyright (C) 2018 Merlok
// Copyright (C) 2018 drHatson
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// crypto commands
//-----------------------------------------------------------------------------
#include "crypto/libpcrypto.h"
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <mbedtls/asn1.h>
#include <mbedtls/aes.h>
#include <mbedtls/cmac.h>
#include <mbedtls/pk.h>
#include <mbedtls/ecdsa.h>
#include <mbedtls/sha256.h>
#include <mbedtls/sha512.h>
#include <mbedtls/ctr_drbg.h>
#include <mbedtls/entropy.h>
#include <mbedtls/error.h>
#include <crypto/asn1utils.h>
#include <util.h>
// NIST Special Publication 800-38A — Recommendation for block cipher modes of operation: methods and techniques, 2001.
int aes_encode(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *output, int length) {
uint8_t iiv[16] = {0};
if (iv)
memcpy(iiv, iv, 16);
mbedtls_aes_context aes;
mbedtls_aes_init(&aes);
if (mbedtls_aes_setkey_enc(&aes, key, 128))
return 1;
if (mbedtls_aes_crypt_cbc(&aes, MBEDTLS_AES_ENCRYPT, length, iiv, input, output))
return 2;
mbedtls_aes_free(&aes);
return 0;
}
int aes_decode(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *output, int length) {
uint8_t iiv[16] = {0};
if (iv)
memcpy(iiv, iv, 16);
mbedtls_aes_context aes;
mbedtls_aes_init(&aes);
if (mbedtls_aes_setkey_dec(&aes, key, 128))
return 1;
if (mbedtls_aes_crypt_cbc(&aes, MBEDTLS_AES_DECRYPT, length, iiv, input, output))
return 2;
mbedtls_aes_free(&aes);
return 0;
}
// NIST Special Publication 800-38B — Recommendation for block cipher modes of operation: The CMAC mode for authentication.
// https://csrc.nist.gov/CSRC/media/Projects/Cryptographic-Standards-and-Guidelines/documents/examples/AES_CMAC.pdf
int aes_cmac(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *mac, int length) {
memset(mac, 0x00, 16);
// NIST 800-38B
return mbedtls_aes_cmac_prf_128(key, MBEDTLS_AES_BLOCK_SIZE, input, length, mac);
}
int aes_cmac8(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *mac, int length) {
uint8_t cmac_tmp[16] = {0};
memset(mac, 0x00, 8);
int res = aes_cmac(iv, key, input, cmac_tmp, length);
if (res)
return res;
for (int i = 0; i < 8; i++)
mac[i] = cmac_tmp[i * 2 + 1];
return 0;
}
static uint8_t fixed_rand_value[250] = {0};
static int fixed_rand(void *rng_state, unsigned char *output, size_t len) {
if (len <= 250) {
memcpy(output, fixed_rand_value, len);
} else {
memset(output, 0x00, len);
}
return 0;
}
int sha256hash(uint8_t *input, int length, uint8_t *hash) {
if (!hash || !input)
return 1;
mbedtls_sha256_context sctx;
mbedtls_sha256_init(&sctx);
mbedtls_sha256_starts(&sctx, 0); // SHA-256, not 224
mbedtls_sha256_update(&sctx, input, length);
mbedtls_sha256_finish(&sctx, hash);
mbedtls_sha256_free(&sctx);
return 0;
}
int sha512hash(uint8_t *input, int length, uint8_t *hash) {
if (!hash || !input)
return 1;
mbedtls_sha512_context sctx;
mbedtls_sha512_init(&sctx);
mbedtls_sha512_starts(&sctx, 0); //SHA-512, not 384
mbedtls_sha512_update(&sctx, input, length);
mbedtls_sha512_finish(&sctx, hash);
mbedtls_sha512_free(&sctx);
return 0;
}
static int ecdsa_init_str(mbedtls_ecdsa_context *ctx, const char *key_d, const char *key_x, const char *key_y) {
if (!ctx)
return 1;
int res;
mbedtls_ecdsa_init(ctx);
res = mbedtls_ecp_group_load(&ctx->grp, MBEDTLS_ECP_DP_SECP256R1); // secp256r1
if (res)
return res;
if (key_d) {
res = mbedtls_mpi_read_string(&ctx->d, 16, key_d);
if (res)
return res;
}
if (key_x && key_y) {
res = mbedtls_ecp_point_read_string(&ctx->Q, 16, key_x, key_y);
if (res)
return res;
}
return 0;
}
static int ecdsa_init(mbedtls_ecdsa_context *ctx, uint8_t *key_d, uint8_t *key_xy) {
if (!ctx)
return 1;
int res;
mbedtls_ecdsa_init(ctx);
res = mbedtls_ecp_group_load(&ctx->grp, MBEDTLS_ECP_DP_SECP256R1); // secp256r1
if (res)
return res;
if (key_d) {
res = mbedtls_mpi_read_binary(&ctx->d, key_d, 32);
if (res)
return res;
}
if (key_xy) {
res = mbedtls_ecp_point_read_binary(&ctx->grp, &ctx->Q, key_xy, 32 * 2 + 1);
if (res)
return res;
}
return 0;
}
int ecdsa_key_create(uint8_t *key_d, uint8_t *key_xy) {
int res;
mbedtls_ecdsa_context ctx;
ecdsa_init(&ctx, NULL, NULL);
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
const char *pers = "ecdsaproxmark";
mbedtls_entropy_init(&entropy);
mbedtls_ctr_drbg_init(&ctr_drbg);
res = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char *)pers, strlen(pers));
if (res)
goto exit;
res = mbedtls_ecdsa_genkey(&ctx, MBEDTLS_ECP_DP_SECP256R1, mbedtls_ctr_drbg_random, &ctr_drbg);
if (res)
goto exit;
res = mbedtls_mpi_write_binary(&ctx.d, key_d, 32);
if (res)
goto exit;
size_t keylen = 0;
uint8_t public_key[200] = {0};
res = mbedtls_ecp_point_write_binary(&ctx.grp, &ctx.Q, MBEDTLS_ECP_PF_UNCOMPRESSED, &keylen, public_key, sizeof(public_key));
if (res)
goto exit;
if (keylen != 65) { // 0x04 <key x 32b><key y 32b>
res = 1;
goto exit;
}
memcpy(key_xy, public_key, 65);
exit:
mbedtls_entropy_free(&entropy);
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_ecdsa_free(&ctx);
return res;
}
char *ecdsa_get_error(int ret) {
static char retstr[300];
memset(retstr, 0x00, sizeof(retstr));
mbedtls_strerror(ret, retstr, sizeof(retstr));
return retstr;
}
int ecdsa_public_key_from_pk(mbedtls_pk_context *pk, uint8_t *key, size_t keylen) {
int res = 0;
size_t realkeylen = 0;
if (keylen < 65)
return 1;
mbedtls_ecdsa_context ctx;
mbedtls_ecdsa_init(&ctx);
res = mbedtls_ecp_group_load(&ctx.grp, MBEDTLS_ECP_DP_SECP256R1); // secp256r1
if (res)
goto exit;
res = mbedtls_ecdsa_from_keypair(&ctx, mbedtls_pk_ec(*pk));
if (res)
goto exit;
res = mbedtls_ecp_point_write_binary(&ctx.grp, &ctx.Q, MBEDTLS_ECP_PF_UNCOMPRESSED, &realkeylen, key, keylen);
if (realkeylen != 65)
res = 2;
exit:
mbedtls_ecdsa_free(&ctx);
return res;
}
int ecdsa_signature_create(uint8_t *key_d, uint8_t *key_xy, uint8_t *input, int length, uint8_t *signature, size_t *signaturelen) {
int res;
*signaturelen = 0;
uint8_t shahash[32] = {0};
res = sha256hash(input, length, shahash);
if (res)
return res;
mbedtls_entropy_context entropy;
mbedtls_ctr_drbg_context ctr_drbg;
const char *pers = "ecdsaproxmark";
mbedtls_entropy_init(&entropy);
mbedtls_ctr_drbg_init(&ctr_drbg);
res = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char *)pers, strlen(pers));
if (res)
goto exit;
mbedtls_ecdsa_context ctx;
ecdsa_init(&ctx, key_d, key_xy);
res = mbedtls_ecdsa_write_signature(&ctx, MBEDTLS_MD_SHA256, shahash, sizeof(shahash), signature, signaturelen, mbedtls_ctr_drbg_random, &ctr_drbg);
exit:
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_ecdsa_free(&ctx);
return res;
}
static int ecdsa_signature_create_test(const char *key_d, const char *key_x, const char *key_y, const char *random, uint8_t *input, int length, uint8_t *signature, size_t *signaturelen) {
int res;
*signaturelen = 0;
uint8_t shahash[32] = {0};
res = sha256hash(input, length, shahash);
if (res)
return res;
int rndlen = 0;
param_gethex_to_eol(random, 0, fixed_rand_value, sizeof(fixed_rand_value), &rndlen);
mbedtls_ecdsa_context ctx;
ecdsa_init_str(&ctx, key_d, key_x, key_y);
res = mbedtls_ecdsa_write_signature(&ctx, MBEDTLS_MD_SHA256, shahash, sizeof(shahash), signature, signaturelen, fixed_rand, NULL);
mbedtls_ecdsa_free(&ctx);
return res;
}
static int ecdsa_signature_verify_keystr(const char *key_x, const char *key_y, uint8_t *input, int length, uint8_t *signature, size_t signaturelen) {
int res;
uint8_t shahash[32] = {0};
res = sha256hash(input, length, shahash);
if (res)
return res;
mbedtls_ecdsa_context ctx;
ecdsa_init_str(&ctx, NULL, key_x, key_y);
res = mbedtls_ecdsa_read_signature(&ctx, shahash, sizeof(shahash), signature, signaturelen);
mbedtls_ecdsa_free(&ctx);
return res;
}
int ecdsa_signature_verify(uint8_t *key_xy, uint8_t *input, int length, uint8_t *signature, size_t signaturelen) {
int res;
uint8_t shahash[32] = {0};
res = sha256hash(input, length, shahash);
if (res)
return res;
mbedtls_ecdsa_context ctx;
ecdsa_init(&ctx, NULL, key_xy);
res = mbedtls_ecdsa_read_signature(&ctx, shahash, sizeof(shahash), signature, signaturelen);
mbedtls_ecdsa_free(&ctx);
return res;
}
#define T_PRIVATE_KEY "C477F9F65C22CCE20657FAA5B2D1D8122336F851A508A1ED04E479C34985BF96"
#define T_Q_X "B7E08AFDFE94BAD3F1DC8C734798BA1C62B3A0AD1E9EA2A38201CD0889BC7A19"
#define T_Q_Y "3603F747959DBF7A4BB226E41928729063ADC7AE43529E61B563BBC606CC5E09"
#define T_K "7A1A7E52797FC8CAAA435D2A4DACE39158504BF204FBE19F14DBB427FAEE50AE"
#define T_R "2B42F576D07F4165FF65D1F3B1500F81E44C316F1F0B3EF57325B69ACA46104F"
#define T_S "DC42C2122D6392CD3E3A993A89502A8198C1886FE69D262C4B329BDB6B63FAF1"
int ecdsa_nist_test(bool verbose) {
int res;
uint8_t input[] = "Example of ECDSA with P-256";
int length = strlen((char *)input);
uint8_t signature[300] = {0};
size_t siglen = 0;
// NIST ecdsa test
if (verbose)
printf(" ECDSA NIST test: ");
// make signature
res = ecdsa_signature_create_test(T_PRIVATE_KEY, T_Q_X, T_Q_Y, T_K, input, length, signature, &siglen);
// printf("res: %x signature[%x]: %s\n", (res<0)?-res:res, siglen, sprint_hex(signature, siglen));
if (res)
goto exit;
// check vectors
uint8_t rval[300] = {0};
uint8_t sval[300] = {0};
res = ecdsa_asn1_get_signature(signature, siglen, rval, sval);
if (res)
goto exit;
int slen = 0;
uint8_t rval_s[33] = {0};
param_gethex_to_eol(T_R, 0, rval_s, sizeof(rval_s), &slen);
uint8_t sval_s[33] = {0};
param_gethex_to_eol(T_S, 0, sval_s, sizeof(sval_s), &slen);
if (strncmp((char *)rval, (char *)rval_s, 32) || strncmp((char *)sval, (char *)sval_s, 32)) {
printf("R or S check error\n");
res = 100;
goto exit;
}
// verify signature
res = ecdsa_signature_verify_keystr(T_Q_X, T_Q_Y, input, length, signature, siglen);
if (res)
goto exit;
// verify wrong signature
input[0] ^= 0xFF;
res = ecdsa_signature_verify_keystr(T_Q_X, T_Q_Y, input, length, signature, siglen);
if (!res) {
res = 1;
goto exit;
}
if (verbose) {
printf("passed\n");
printf(" ECDSA binary signature create/check test: ");
}
// random ecdsa test
uint8_t key_d[32] = {0};
uint8_t key_xy[32 * 2 + 2] = {0};
memset(signature, 0x00, sizeof(signature));
siglen = 0;
res = ecdsa_key_create(key_d, key_xy);
if (res)
goto exit;
res = ecdsa_signature_create(key_d, key_xy, input, length, signature, &siglen);
if (res)
goto exit;
res = ecdsa_signature_verify(key_xy, input, length, signature, siglen);
if (res)
goto exit;
input[0] ^= 0xFF;
res = ecdsa_signature_verify(key_xy, input, length, signature, siglen);
if (!res)
goto exit;
if (verbose)
printf("passed\n\n");
return 0;
exit:
if (verbose)
printf("failed\n\n");
return res;
}