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ec_utils.c
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/*
* Copyright (C) 2017 - This file is part of libecc project
*
* Authors:
* Ryad BENADJILA <[email protected]>
* Arnaud EBALARD <[email protected]>
* Jean-Pierre FLORI <[email protected]>
*
* Contributors:
* Nicolas VIVET <[email protected]>
* Karim KHALFALLAH <[email protected]>
*
* This software is licensed under a dual BSD and GPL v2 license.
* See LICENSE file at the root folder of the project.
*/
#ifdef WITH_STDLIB
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#endif
#include "../libsig.h"
#define HDR_MAGIC 0x34215609
typedef enum {
IMAGE_TYPE0 = 0,
IMAGE_TYPE1 = 1,
IMAGE_TYPE2 = 2,
IMAGE_TYPE3 = 3,
/* Info: You can add more image header types */
} image_type;
/* Generic header to prepend data */
typedef struct {
u32 magic; /* header header */
u32 type; /* Type of the signed image */
u32 version; /* Version */
u32 len; /* length of data after header */
u32 siglen; /* length of sig (on header + data) */
} ATTRIBUTE_PACKED metadata_hdr;
/* Max stack working buffer size */
#define MAX_BUF_LEN 8192
typedef enum {
RAWBIN,
DOTH,
} export_file_type;
static int export_private_key(FILE * file, const char *name,
const ec_priv_key *priv_key,
export_file_type file_type)
{
u8 export_buf_size = EC_STRUCTURED_PRIV_KEY_EXPORT_SIZE(priv_key);
u8 priv_key_buf[EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE];
int ret;
u32 i;
size_t written;
priv_key_check_initialized(priv_key);
MUST_HAVE(file != NULL);
/* Serialize the private key to a buffer */
ret = ec_structured_priv_key_export_to_buf(priv_key, priv_key_buf,
export_buf_size);
if (ret) {
printf("Error exporting private key to buffer\n");
ret = -1;
goto err;
}
/* Export the private key to the file */
switch (file_type) {
case DOTH:
MUST_HAVE(name != NULL);
fprintf(file, "const char %s[] = { ", name);
for (i = 0; i < export_buf_size; i++) {
fprintf(file, "0x%02x", priv_key_buf[i]);
if (i != export_buf_size) {
fprintf(file, ", ");
}
}
fprintf(file, "};\n");
ret = 0;
break;
case RAWBIN:
written = fwrite(priv_key_buf, 1, export_buf_size, file);
if(written != export_buf_size){
ret = -1;
goto err;
}
ret = 0;
break;
default:
ret = -1;
}
err:
return ret;
}
static int export_public_key(FILE * file, const char *name,
const ec_pub_key *pub_key,
export_file_type file_type)
{
u8 pub_key_buf[EC_STRUCTURED_PUB_KEY_MAX_EXPORT_SIZE];
u8 export_buf_size;
int ret;
u32 i;
size_t written;
pub_key_check_initialized(pub_key);
MUST_HAVE(file != NULL);
/* Serialize the public key to a buffer */
export_buf_size = EC_STRUCTURED_PUB_KEY_EXPORT_SIZE(pub_key);
ret = ec_structured_pub_key_export_to_buf(pub_key, pub_key_buf,
export_buf_size);
if (ret) {
printf("Error exporting public key to buffer\n");
ret = -1;
goto err;
}
/* Export the public key to the file */
switch (file_type) {
case DOTH:
MUST_HAVE(name != NULL);
fprintf(file, "const char %s[] = { ", name);
for (i = 0; i < export_buf_size; i++) {
fprintf(file, "0x%02x", pub_key_buf[i]);
if (i != export_buf_size) {
fprintf(file, ", ");
}
}
fprintf(file, "};\n");
ret = 0;
break;
case RAWBIN:
written = fwrite(pub_key_buf, 1, export_buf_size, file);
if(written != export_buf_size){
ret = -1;
goto err;
}
ret = 0;
break;
default:
ret = -1;
}
err:
return ret;
}
static int string_to_params(const char *ec_name, const char *ec_sig_name,
ec_sig_alg_type * sig_type,
const ec_str_params ** ec_str_p,
const char *hash_name, hash_alg_type * hash_type)
{
const ec_str_params *curve_params;
const ec_sig_mapping *sm;
const hash_mapping *hm;
u32 curve_name_len;
if (sig_type != NULL) {
/* Get sig type from signature alg name */
sm = get_sig_by_name(ec_sig_name);
if (!sm) {
printf("Error: signature type %s is unknown!\n",
ec_sig_name);
goto err;
}
*sig_type = sm->type;
}
if (ec_str_p != NULL) {
/* Get curve params from curve name */
curve_name_len = local_strlen((const char *)ec_name) + 1;
if(curve_name_len > 255){
/* Sanity check */
goto err;
}
curve_params = ec_get_curve_params_by_name((const u8 *)ec_name,
(u8)curve_name_len);
if (!curve_params) {
printf("Error: EC curve %s is unknown!\n", ec_name);
goto err;
}
*ec_str_p = curve_params;
}
if (hash_type != NULL) {
/* Get hash type from hash alg name */
hm = get_hash_by_name(hash_name);
if (!hm) {
printf("Error: hash function %s is unknown!\n",
hash_name);
goto err;
}
*hash_type = hm->type;
}
return 0;
err:
return -1;
}
static int generate_and_export_key_pair(const char *ec_name,
const char *ec_sig_name,
const char *fname_prefix)
{
const ec_str_params *ec_str_p;
char fname[MAX_BUF_LEN];
char kname[MAX_BUF_LEN];
const u16 fname_len = sizeof(fname);
const u16 kname_len = sizeof(kname);
u16 prefix_len;
ec_sig_alg_type sig_type;
ec_params params;
ec_key_pair kp;
FILE *file;
int ret;
aff_pt Q_aff;
MUST_HAVE(ec_name != NULL);
MUST_HAVE(fname_prefix != NULL);
MUST_HAVE(ec_sig_name != NULL);
/* Get parameters from pretty names */
ret = string_to_params(ec_name, ec_sig_name, &sig_type, &ec_str_p,
NULL, NULL);
if (ret) {
goto err;
}
/* Import the parameters */
import_params(¶ms, ec_str_p);
/* Generate the key pair */
ec_key_pair_gen(&kp, ¶ms, sig_type);
/* Get the affine representation and go back to projective for the public key.
* This avoids ambiguity when exporting the point, and is mostly here
* for compatibility with external libraries.
*/
prj_pt_to_aff(&Q_aff, &(kp.pub_key.y));
ec_shortw_aff_to_prj(&(kp.pub_key.y), &Q_aff);
/*************************/
/* Export the private key to the raw binary file */
prefix_len = (u16)local_strnlen(fname_prefix, fname_len);
local_memset(fname, 0, fname_len);
local_memcpy(fname, fname_prefix, prefix_len);
local_strncat(fname, "_private_key.bin", fname_len - prefix_len);
file = fopen(fname, "w");
if (file == NULL) {
printf("Error: file %s cannot be opened\n", fname);
goto err;
}
ret = export_private_key(file, NULL, &(kp.priv_key), RAWBIN);
fclose(file);
if (ret) {
printf("Error exporting the private key\n");
goto err;
}
/* Export the private key to the .h file */
local_memset(fname, 0, fname_len);
local_memcpy(fname, fname_prefix, prefix_len);
local_strncat(fname, "_private_key.h", fname_len - prefix_len);
file = fopen(fname, "w");
if (file == NULL) {
printf("Error: file %s cannot be opened\n", fname);
goto err;
}
snprintf(kname, kname_len, "%s_%s_private_key", ec_name, ec_sig_name);
ret = export_private_key(file, kname, &(kp.priv_key), DOTH);
fclose(file);
if (ret) {
printf("Error: error exporting the private key\n");
goto err;
}
/*************************/
/* Export the public key to the raw binary file */
local_memset(fname, 0, fname_len);
local_memcpy(fname, fname_prefix, prefix_len);
local_strncat(fname, "_public_key.bin", fname_len - prefix_len);
file = fopen(fname, "w");
if (file == NULL) {
printf("Error: file %s cannot be opened\n", fname);
goto err;
}
ret = export_public_key(file, NULL, &(kp.pub_key), RAWBIN);
fclose(file);
if (ret) {
printf("Error exporting the public key\n");
goto err;
}
/* Export the public key to the .h file */
local_memset(fname, 0, fname_len);
local_memcpy(fname, fname_prefix, prefix_len);
local_strncat(fname, "_public_key.h", fname_len - prefix_len);
file = fopen(fname, "w");
if (file == NULL) {
printf("Error: file %s cannot be opened\n", fname);
goto err;
}
snprintf(kname, kname_len, "%s_%s_public_key", ec_name, ec_sig_name);
ret = export_public_key(file, kname, &(kp.pub_key), DOTH);
fclose(file);
if (ret) {
printf("Error exporting the public key\n");
goto err;
}
return 0;
err:
return -1;
}
static int store_sig(const char *in_fname, const char *out_fname,
const u8 *sig, u32 siglen,
ec_sig_alg_type sig_type, hash_alg_type hash_type,
const u8 curve_name[MAX_CURVE_NAME_LEN],
metadata_hdr * hdr)
{
FILE *in_file = NULL, *out_file = NULL;
u8 buf[MAX_BUF_LEN];
size_t read, written;
int ret;
MUST_HAVE(EC_STRUCTURED_SIG_EXPORT_SIZE(siglen) <= sizeof(buf));
/* Import the data from the input file */
in_file = fopen(in_fname, "r");
if (in_file == NULL) {
printf("Error: file %s cannot be opened\n", in_fname);
goto err;
}
out_file = fopen(out_fname, "w");
if (out_file == NULL) {
printf("Error: file %s cannot be opened\n", out_fname);
goto err;
}
if (hdr != NULL) {
/* Write the metadata header as a prepending information */
written = fwrite(hdr, 1, sizeof(metadata_hdr), out_file);
if (written != sizeof(metadata_hdr)) {
fclose(in_file);
fclose(out_file);
in_file = out_file = NULL;
goto err;
}
}
while (1) {
read = fread(buf, 1, sizeof(buf), in_file);
written = fwrite(buf, 1, read, out_file);
if (written != read) {
printf("Error: error when writing to %s\n",
out_fname);
fclose(in_file);
fclose(out_file);
in_file = out_file = NULL;
goto err;
}
if (read != sizeof(buf)) {
if (feof(in_file)) {
/* EOF */
break;
} else {
printf("Error: error when reading from %s\n",
in_fname);
fclose(in_file);
fclose(out_file);
in_file = out_file = NULL;
goto err;
}
}
}
/* Compute the structured signature */
ret = ec_structured_sig_export_to_buf(sig, siglen, buf, sizeof(buf),
sig_type, hash_type, curve_name);
if (ret) {
printf("Error: error when exporting signature to structured buffer\n");
goto err;
}
/* Store the signature buffer */
written =
fwrite(buf, 1, EC_STRUCTURED_SIG_EXPORT_SIZE(siglen),
out_file);
if (written != EC_STRUCTURED_SIG_EXPORT_SIZE(siglen)) {
printf("Error: error when writing to %s\n", out_fname);
fclose(in_file);
fclose(out_file);
in_file = out_file = NULL;
goto err;
}
fclose(in_file);
fclose(out_file);
return 0;
err:
if(in_file != NULL){
fclose(in_file);
}
if(out_file != NULL){
fclose(out_file);
}
return -1;
}
/* Get the raw size of a file */
static int get_file_size(const char *in_fname, size_t *outsz)
{
FILE *in_file;
long size;
*outsz = 0;
in_file = fopen(in_fname, "r");
if (in_file == NULL) {
printf("Error: file %s cannot be opened\n", in_fname);
goto err;
}
/* Compute the size of the file */
if (fseek(in_file, 0L, SEEK_END)) {
printf("Error: file %s cannot be seeked\n", in_fname);
goto err_close;
}
size = ftell(in_file);
if (size < 0) {
printf("Error: cannot compute file %s size\n", in_fname);
goto err_close;
}
/* Check overflow */
if ((unsigned long)size > ((u32)~0)) {
printf("Error: file %s size %ld overflow (>= 2^32)\n",
in_fname, size);
goto err_close;
}
*outsz = (u32)size;
fclose(in_file);
return 0;
err_close:
fclose(in_file);
err:
return -1;
}
/* Generate a proper handler from a given type and other information */
static int generate_metadata_hdr(metadata_hdr * hdr, const char *hdr_type,
const char *version, size_t len, u8 siglen)
{
unsigned long ver;
char *endptr; /* for strtoul() */
/* The magic value */
hdr->magic = HDR_MAGIC;
/* The given version */
ver = strtoul(version, &endptr, 0);
if (*endptr != '\0') {
printf("Error: error getting provided version %s\n", version);
goto err;
}
if ((ver & 0xffffffff) != ver) {
printf("Error: provided version %s is too long!\n", version);
goto err;
}
hdr->version = (u32)ver;
/* The image type */
if (are_str_equal(hdr_type, "IMAGE_TYPE0")) {
hdr->type = IMAGE_TYPE0;
} else if (are_str_equal(hdr_type, "IMAGE_TYPE1")) {
hdr->type = IMAGE_TYPE0;
} else if (are_str_equal(hdr_type, "IMAGE_TYPE2")) {
hdr->type = IMAGE_TYPE0;
} else if (are_str_equal(hdr_type, "IMAGE_TYPE3")) {
hdr->type = IMAGE_TYPE3;
} else {
printf("Error: unknown header type %s\n", hdr_type);
goto err;
}
/* The length without the signature */
if ((len & 0xffffffff) != len) {
printf("Error: provided length value %lu is too long!\n", (unsigned long)len);
goto err;
}
hdr->len = (u32)len;
/* The signature length */
hdr->siglen = siglen;
return 0;
err:
return -1;
}
/*
* Sign data from file and append signature
*/
static int sign_bin_file(const char *ec_name, const char *ec_sig_name,
const char *hash_algorithm, const char *in_fname,
const char *in_key_fname,
const char *out_fname, const char *hdr_type,
const char *version)
{
u8 sig[EC_MAX_SIGLEN];
u8 buf[MAX_BUF_LEN];
u8 siglen;
FILE *in_file;
ec_key_pair key_pair;
FILE *in_key_file;
const ec_str_params *ec_str_p;
ec_params params;
int ret;
ec_sig_alg_type sig_type;
hash_alg_type hash_type;
u8 priv_key_buf[EC_STRUCTURED_PRIV_KEY_MAX_EXPORT_SIZE];
u8 priv_key_buf_len;
size_t raw_data_len;
metadata_hdr hdr;
size_t read, to_read;
int eof;
struct ec_sign_context sig_ctx;
MUST_HAVE(ec_name != NULL);
/************************************/
/* Get parameters from pretty names */
if (string_to_params
(ec_name, ec_sig_name, &sig_type, &ec_str_p, hash_algorithm,
&hash_type)) {
goto err;
}
/* Import the parameters */
import_params(¶ms, ec_str_p);
/************************************/
/* Import the private key from the file */
in_key_file = fopen(in_key_fname, "r");
if (in_key_file == NULL) {
printf("Error: file %s cannot be opened\n", in_key_fname);
goto err;
}
priv_key_buf_len = (u8)fread(priv_key_buf, 1, sizeof(priv_key_buf),
in_key_file);
fclose(in_key_file);
ret = ec_structured_key_pair_import_from_priv_key_buf(&key_pair,
¶ms,
priv_key_buf,
priv_key_buf_len,
sig_type);
if (ret) {
printf("Error: error when importing key pair from %s\n",
in_key_fname);
goto err;
}
ret = get_file_size(in_fname, &raw_data_len);
if (ret) {
printf("Error: cannot retrieve file %s size\n", in_fname);
goto err;
}
ret = ec_get_sig_len(¶ms, sig_type, hash_type, &siglen);
if (ret) {
printf("Error getting effective signature length from %s\n",
(const char *)(ec_str_p->name->buf));
goto err;
}
/* Structured export case, we forge a header */
if((hdr_type != NULL) && (version != NULL)){
/************************************/
/* Forge the header */
ret = generate_metadata_hdr(&hdr, hdr_type, version, raw_data_len,
EC_STRUCTURED_SIG_EXPORT_SIZE(siglen));
if (ret) {
printf("Error: error when generating metadata\n");
goto err;
}
}
/*
* Initialize signature context and start signature computation
* with generated metadata header.
*/
ret = ec_sign_init(&sig_ctx, &key_pair, sig_type, hash_type);
if (ret) {
printf("Error: error when signing\n");
goto err;
}
/* Structured export case, we prepend the header in the signature */
if((hdr_type != NULL) && (version != NULL)){
ret = ec_sign_update(&sig_ctx, (const u8 *)&hdr, sizeof(metadata_hdr));
if (ret) {
printf("Error: error when signing\n");
goto err;
}
}
/*
* Read file content chunk by chunk up to file length, passing each
* chunk to signature update function
*/
in_file = fopen(in_fname, "r");
if (in_file == NULL) {
printf("Error: file %s cannot be opened\n", in_fname);
goto err;
}
eof = 0;
clearerr(in_file);
while (raw_data_len && !eof) {
to_read =
(raw_data_len <
sizeof(buf)) ? raw_data_len : sizeof(buf);
read = fread(buf, 1, to_read, in_file);
if (read != to_read) {
/* Check if this was EOF */
ret = feof(in_file);
clearerr(in_file);
if (ret) {
eof = 1;
}
}
if (read > raw_data_len) {
/* we read more than expected: leave! */
break;
}
raw_data_len -= read;
ret = ec_sign_update(&sig_ctx, buf, (u32)read);
if (ret) {
break;
}
}
fclose(in_file);
if (raw_data_len) {
printf("Error: unable to read full file content\n");
goto err;
}
/* We can now complete signature generation */
ret = ec_sign_finalize(&sig_ctx, sig, siglen);
if (ret) {
printf("Error: error when signing\n");
goto err;
}
/* Structured export case, forge the full structured file
* with HEADER || raw_binary || signature
*/
if((hdr_type != NULL) && (version != NULL)){
/***********************************/
/* Store the header, the raw data of the file as well as the signature */
ret = store_sig(in_fname, out_fname, sig, siglen, sig_type,
hash_type, params.curve_name, &hdr);
if (ret) {
printf("Error: error when storing signature to %s\n",
out_fname);
goto err;
}
}
else{
/* Store the raw binary signature in the output file */
FILE *out_file;
size_t written;
out_file = fopen(out_fname, "w");
if (out_file == NULL) {
printf("Error: file %s cannot be opened\n", out_fname);
goto err;
}
written = fwrite(sig, 1, siglen, out_file);
fclose(out_file);
if (written != siglen) {
printf("Error: error when writing to %s\n",
out_fname);
goto err;
}
}
return 0;
err:
return -1;
}
/* Dump metadata header */
static int dump_hdr_info(const metadata_hdr * hdr)
{
/* Dump the header */
printf("Metadata header info:\n");
printf(" magic = 0x%08x\n", hdr->magic);
switch (hdr->type) {
case IMAGE_TYPE0:
printf(" type = IMAGE_TYPE0\n");
break;
case IMAGE_TYPE1:
printf(" type = IMAGE_TYPE1\n");
break;
case IMAGE_TYPE2:
printf(" type = IMAGE_TYPE2\n");
break;
case IMAGE_TYPE3:
printf(" type = IMAGE_TYPE3\n");
break;
default:
printf(" type %u unknown!\n", hdr->type);
break;
}
printf(" version = 0x%08x\n", hdr->version);
printf(" len = 0x%08x\n", hdr->len);
printf(" siglen = 0x%08x\n", hdr->siglen);
return 0;
}
/*
* Verify signature data from file with appended signature
*/
static int verify_bin_file(const char *ec_name, const char *ec_sig_name,
const char *hash_algorithm,
const char *in_fname,
const char *in_key_fname, const char *in_sig_fname)
{
u8 st_sig[EC_STRUCTURED_SIG_EXPORT_SIZE(EC_MAX_SIGLEN)];
u8 stored_curve_name[MAX_CURVE_NAME_LEN];
u8 pub_key_buf[EC_STRUCTURED_PUB_KEY_MAX_EXPORT_SIZE];
struct ec_verify_context verif_ctx;
ec_sig_alg_type stored_sig_type;
hash_alg_type stored_hash_type;
const ec_str_params *ec_str_p;
ec_sig_alg_type sig_type;
hash_alg_type hash_type;
u8 sig[EC_MAX_SIGLEN];
u8 siglen, st_siglen;
size_t read, to_read;
u8 buf[MAX_BUF_LEN];
u8 pub_key_buf_len;
size_t raw_data_len;
ec_pub_key pub_key;
FILE *in_key_file;
FILE *in_sig_file;
ec_params params;
metadata_hdr hdr;
size_t exp_len;
FILE *in_file;
int ret, eof;
MUST_HAVE(ec_name != NULL);
/************************************/
/* Get parameters from pretty names */
if (string_to_params(ec_name, ec_sig_name, &sig_type, &ec_str_p,
hash_algorithm, &hash_type)) {
goto err;
}
/* Import the parameters */
import_params(¶ms, ec_str_p);
ret = ec_get_sig_len(¶ms, sig_type, hash_type, &siglen);
if (ret) {
printf("Error getting effective signature length from %s\n",
(const char *)(ec_str_p->name->buf));
goto err;
}
/************************************/
/* Import the public key from the file */
in_key_file = fopen(in_key_fname, "r");
if (in_key_file == NULL) {
printf("Error: file %s cannot be opened\n", in_key_fname);
goto err;
}
pub_key_buf_len =(u8)fread(pub_key_buf, 1, sizeof(pub_key_buf),
in_key_file);
fclose(in_key_file);
ret = ec_structured_pub_key_import_from_buf(&pub_key, ¶ms,
pub_key_buf,
pub_key_buf_len, sig_type);
if (ret) {
printf("Error: error when importing public key from %s\n",
in_key_fname);
goto err;
}
/* Let's first get file size */
ret = get_file_size(in_fname, &raw_data_len);
if (ret) {
printf("Error: cannot retrieve file %s size\n", in_fname);
goto err;
}
/* Open main file to verify ... */
in_file = fopen(in_fname, "r");
if (in_file == NULL) {
printf("Error: file %s cannot be opened\n", in_fname);
goto err;
}
/*
* We are in 'structured' mode, read the header and get the information
* from it
*/
if (in_sig_fname == NULL) {
/* ... and first read metadata header */
read = fread(&hdr, 1, sizeof(hdr), in_file);
if (read != sizeof(hdr)) {
printf("Error: unable to read metadata header "
"from file\n");
fclose(in_file);
goto err;
}
/* Sanity checks on the header we get */
if (hdr.magic != HDR_MAGIC) {
printf("Error: got magic 0x%08x instead of 0x%08x "
"from metadata header\n", hdr.magic, HDR_MAGIC);
goto err;
}
st_siglen = EC_STRUCTURED_SIG_EXPORT_SIZE(siglen);
MUST_HAVE(raw_data_len > (sizeof(hdr) + st_siglen));
exp_len = raw_data_len - sizeof(hdr) - st_siglen;
if (hdr.len != exp_len) {
printf("Error: got raw size of %u instead of %lu from "
"metadata header\n", hdr.len,
(unsigned long)exp_len);
goto err;
}
if (hdr.siglen != st_siglen) {
printf("Error: got siglen %u instead of %d from "
"metadata header\n", hdr.siglen, siglen);
goto err;
}
/* Dump the header */
dump_hdr_info(&hdr);
/*
* We now need to seek in file to get structured signature.
* Before doing that, let's first check size is large enough.
*/
if (raw_data_len < (sizeof(hdr) + st_siglen)) {
goto err;
}
ret = fseek(in_file, (long)(raw_data_len - st_siglen),
SEEK_SET);
if (ret) {
printf("Error: file %s cannot be seeked\n", in_fname);
goto err;
}
read = fread(st_sig, 1, st_siglen, in_file);
if (read != st_siglen) {
printf("Error: unable to read structure sig from "
"file\n");
fclose(in_file);
goto err;
}
/* Import the signature from the structured signature buffer */
ret = ec_structured_sig_import_from_buf(sig, siglen,
st_sig, st_siglen,
&stored_sig_type,
&stored_hash_type,
stored_curve_name);
if (ret) {
printf("Error: error when importing signature "
"from %s\n", in_fname);
goto err;
}
if (stored_sig_type != sig_type) {
printf("Error: signature type imported from signature "
"mismatches with %s\n", ec_sig_name);
goto err;
}
if (stored_hash_type != hash_type) {
printf("Error: hash algorithm type imported from "
"signature mismatches with %s\n",
hash_algorithm);
goto err;
}
if (!are_str_equal((char *)stored_curve_name,
(char *)params.curve_name)) {
printf("Error: curve type '%s' imported from signature "
"mismatches with '%s'\n", stored_curve_name,
params.curve_name);
goto err;
}
/*
* Get back to the beginning of file, at the beginning of header
*/
if (fseek(in_file, 0, SEEK_SET)) {
printf("Error: file %s cannot be seeked\n", in_fname);
goto err;
}
exp_len += sizeof(hdr);
} else {
/* Get the signature size */
ret = get_file_size(in_sig_fname, &to_read);
if (ret) {
printf("Error: cannot retrieve file %s size\n",
in_sig_fname);
goto err;
}
if((to_read > EC_MAX_SIGLEN) || (to_read > 255)){
/* This is not an expected size, get out */
printf("Error: size %d of signature in %s is > max "
"signature size %d or > 255",
(int)to_read, in_sig_fname, EC_MAX_SIGLEN);
goto err;
}
siglen = (u8)to_read;
/* Read the raw signature from the signature file */
in_sig_file = fopen(in_sig_fname, "r");
if (in_sig_file == NULL) {
printf("Error: file %s cannot be opened\n",
in_sig_fname);
goto err;
}
read = fread(&sig, 1, siglen, in_sig_file);
fclose(in_sig_file);
if (read != siglen) {
printf("Error: unable to read signature from %s\n",
in_sig_fname);
goto err;
}
exp_len = raw_data_len;
}
/*
* ... and read file content chunk by chunk to compute signature
*/
ret = ec_verify_init(&verif_ctx, &pub_key, sig, siglen,
sig_type, hash_type);
if (ret) {
goto err;
}
eof = 0;
clearerr(in_file);
while (exp_len && !eof) {
to_read = (exp_len < sizeof(buf)) ? exp_len : sizeof(buf);
read = fread(buf, 1, to_read, in_file);
if (read != to_read) {
/* Check if this was EOF */
ret = feof(in_file);
clearerr(in_file);
if (ret) {
eof = 1;
}
}
if (read > exp_len) {
/* we read more than expected: leave! */
break;
}
exp_len -= read;
ret = ec_verify_update(&verif_ctx, buf, (u32)read);
if (ret) {
break;
}
}
fclose(in_file);
if (exp_len) {