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#include "lib6.h"
#include "lib5.h"
#include "lib4.h"
#include "lib3.h"
#include "lib2.h"
#include "lib.h"
int rsa_sign_bignum(BIGNUM *message, BIGNUM *signed_message, struct rsa_key_bignum *private)
{
rsa_encrypt_bignum(message, signed_message, private);
}
int rsa_verify_bignum(BIGNUM *signed_message, BIGNUM *org_message, struct rsa_key_bignum *public)
{
BIGNUM *res = BN_new();
int ret = -1;
rsa_decrypt_bignum(signed_message, res, public);
ret = BN_cmp(res, org_message);
printf("\nverfied mess ret: %i, message:\n", ret);
BN_print(out, res);
printf("\n");
BN_free(res);
return ret == 0;
}
/**
* construct a VALID pkcs_padding
**/
void pkcs1_5_padding(char *message, char *result, unsigned int target_length_byte)
{
SHA1Context sha1;
char sha1_hash[20];
int i;
memset(result, 0xff, target_length_byte);
result[0] = 0x00;
result[1] = 0x01;
result[target_length_byte-21] = 0x00;
// TODO ASN.1 things
SHA1Reset(&sha1);
SHA1Input(&sha1, message, strlen(message));
SHA1Result(&sha1);
memcpy(sha1_hash, &(sha1.Message_Digest), 20);
for(i = 20;i>0;i--)
result[target_length_byte-i] = sha1_hash[20-i];
}
int pkcs1_5_padding_verify(char *to_verify, int len, char *message)
{
char result[1024/8];
int i;
// construct the padding how the expect it and than compare
pkcs1_5_padding(message, result, 1024/8);
// printf both paddings
char buf[(1024/8)*2];
hex_binary_to_string(result, buf, 1024/8);
printf("expected padding:\n%s\n", buf);
hex_binary_to_string(to_verify, buf, len);
printf("got:\n%s\n", buf);
return memcmp(to_verify, result, 128) == 0;
}
int shitty_pkcs1_5_padding_verify(char *to_verify, int len, char *message)
{
int i = 2;
SHA1Context sha1;
char sha1_hash[20];
if (len < 2 && to_verify[0] != 0x00 && to_verify[1] != 0x01)
return 0;
// search for the next 0x00 no matter what's in between
while(to_verify[i] != 0x00)
i++;
i++;
// TODO check asn.1 things
// verfiy the hash
SHA1Reset(&sha1);
SHA1Input(&sha1, message, strlen(message));
SHA1Result(&sha1);
memcpy(sha1_hash, &(sha1.Message_Digest), 20);
int j;
for(j=0;j<20;j++, i++) {
if (to_verify[i] != sha1_hash[j])
return 0;
}
return 1;
}
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