int
crypto_sign_detached(unsigned char *sig, unsigned long long *siglen_p,
const unsigned char *m, unsigned long long mlen,
const unsigned char *sk)
{
return crypto_sign_ed25519_detached(sig, siglen_p, m, mlen, sk);
}
int
crypto_sign_ed25519(unsigned char *sm, unsigned long long *smlen_p,
const unsigned char *m, unsigned long long mlen,
const unsigned char *sk)
{
unsigned long long siglen;
memmove(sm + crypto_sign_ed25519_BYTES, m, mlen);
/* LCOV_EXCL_START */
if (crypto_sign_ed25519_detached(
sm, &siglen, sm + crypto_sign_ed25519_BYTES, mlen, sk) != 0 ||
siglen != crypto_sign_ed25519_BYTES) {
if (smlen_p != NULL) {
*smlen_p = 0;
}
memset(sm, 0, mlen + crypto_sign_ed25519_BYTES);
return -1;
}
/* LCOV_EXCL_STOP */
if (smlen_p != NULL) {
*smlen_p = mlen + siglen;
}
return 0;
}
int sign_file(char *secret_key_name, char *file_name, char *out_file_name) {
int error = 0;
unsigned char secret_key[crypto_sign_ed25519_SECRETKEYBYTES];
unsigned long long signature_final_size;
unsigned char signature[crypto_sign_ed25519_BYTES];
size_t file_size;
size_t read;
size_t written;
FILE *secret_key_file = NULL;
FILE *target_file = NULL;
FILE *out_file = NULL;
unsigned char *file_contents = NULL;
secret_key_file = fopen(secret_key_name, "r");
if (secret_key_file == NULL) {
perror("opening secret key file");
error = -1;
goto out;
}
target_file = fopen(file_name, "r");
if (target_file == NULL) {
perror("opening target file");
error = -1;
goto out;
}
out_file = fopen(out_file_name, "w");
if (out_file == NULL) {
perror("opening output file");
error = -1;
goto out;
}
error = get_file_size(target_file, &file_size);
if (error != 0) {
perror("Getting file size");
goto out;
}
file_contents = malloc(file_size);
if (file_contents == NULL) {
fprintf(stderr, "Could not allocate memory\n");
error = -1;
goto out;
}
read = fread(secret_key, sizeof(secret_key), 1, secret_key_file);
if (read != 1) {
fprintf(stderr, "Invalid secret key file\n");
error = -1;
goto out;
} else if (ferror(secret_key_file) != 0) {
perror("reading secret key file");
error = -1;
goto out;
}
read = fread(file_contents, file_size, 1, target_file);
if (read != 1 || ferror(target_file) != 0) {
perror("Reading target file");
error = -1;
goto out;
}
written = fwrite(file_contents, file_size, 1, out_file);
if (ferror(out_file) != 0) {
perror("Writing out file");
error = -1;
goto out;
}
error = crypto_sign_ed25519_detached(signature, &signature_final_size,
file_contents, file_size, secret_key);
if (error != 0) {
fprintf(stderr, "Signature\n");
error = -1;
goto out;
}
written = fwrite(SIGNATURE_MAGIC_STRING, sizeof(SIGNATURE_MAGIC_STRING), 1, out_file);
if (written != 1 || ferror(out_file) != 0) {
perror("writing magic string to out file");
error = -1;
goto out;
}
written = fwrite(&signature, sizeof(signature), 1, out_file);
if (written != 1 || ferror(out_file) != 0) {
perror("writing out file");
error = -1;
goto out;
}
#if DEBUG
printf("Secret key:\n");
print_bytes(secret_key, sizeof(secret_key));
printf("Signature:\n");
print_bytes(signature, sizeof(signature));
#endif
out:
fclose(target_file);
fclose(secret_key_file);
fclose(out_file);
free(file_contents);
return error;
}
