add salt header

This commit is contained in:
Gregory 2019-04-06 21:25:04 +03:00
parent 41dcf6b7dd
commit b807f0a3bb
2 changed files with 82 additions and 10 deletions

View file

@ -1,29 +1,33 @@
// ENCRYPTING
1. "openssl des-ecb -S a"
1. "openssl des-ecb -S a"
prompts to enter password, generate key with given pass and salt,
prepend salt header.
2. "openssl des-ecb -pass pass:asd"
2. "openssl des-ecb -pass pass:asd"
generate salt and key, prepend salt header.
3. "openssl des-ecb -S a -pass:asd"
3. "openssl des-ecb -S a -pass:asd"
generate key from givent salt and pass, prepend header.
4. "openssl des-ecb -S a -pass:asd -K 1"
encrypt with GIVEN key, prepend GIVEN salt hedaer.
4. "openssl des-ecb -S a -pass:asd -K 1"
encrypt with GIVEN key, prepend GIVEN salt headaer.
5. "openssl des-ecb -K 1"
5. "openssl des-ecb -K 1"
encrypt with given key, doesn't generate and prepend salt.
6. "openssl des-ecb -S 0 -pass pass:asd -P -pbkdf2"
6. "openssl des-ecb -S 0 -pass pass:asd -P -pbkdf2"
generate key using PKCS5_PBKDF2_HMAC with 10000 iteration,
8 byte salt, 3 byte key, sha256 hash function
8 byte salt, 3 byte key, sha256 hash function, prepend salt header.
// DECRYPTING
7. "echo -n Salted__ | openssl des-ecb -d"
7. "echo -n Salted__ | openssl des-ecb -d"
prompts to enter password, generate key but fails to decode.
8. "echo -n Salted__aaaaaaaa | openssl des-ecb -d"
8. "echo -n Salted__aaaaaaaa | openssl des-ecb -d"
prompts to enter password, generate key but fails to validate padding.
9. openssl doesn't expect "Salted__" header only when -K or -S flag supplied
(or both simultaneously, in this case salt is discarded),
in any other case salt should be readed from message.

View file

@ -1,8 +1,70 @@
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include "ft_des.h"
#include "ft_pbkdf2.h"
#include "libft.h"
static void get_pass
(
char pass[128]
)
{
char *first_try[128];
char *second_try[128];
ft_bzero(first_try, 128);
ft_bzero(second_try, 128);
ft_strcpy((char *)first_try, getpass("enter password:"));
ft_strcpy((char *)second_try, getpass("retype password:"));
if (ft_strcmp((const char *)first_try, (const char *)second_try) != 0)
ft_des_print_error("passwords doesn't match");
ft_strcpy(pass, (const char *)first_try);
}
static void generate_salt
(
char salt[FT_DES_BYTE_BLOCK_SIZE]
)
{
int fd;
fd = open("/dev/random", O_RDONLY);
if (fd == -1)
{
perror("des");
exit(1);
}
read(fd, salt, FT_DES_BYTE_BLOCK_SIZE);
}
static void no_arguments
(
t_des_ctx *ctx,
t_pbkdf2_sha256_ctx *pbkdf_ctx
)
{
char pass[128];
char salt[FT_DES_BYTE_BLOCK_SIZE];
t_byte1 key[FT_DES_BYTE_BLOCK_SIZE];
get_pass(pass);
generate_salt(salt);
pbkdf_ctx->iterations = 10000;
pbkdf_ctx->key = key;
pbkdf_ctx->salt_len = FT_DES_BYTE_BLOCK_SIZE;
pbkdf_ctx->pass = (t_byte1 *)pass;
pbkdf_ctx->salt = (t_byte1 *)salt;
pbkdf_ctx->pass_len = ft_strlen((char *)pass);
pbkdf_ctx->key_len = FT_DES_BYTE_BLOCK_SIZE;
ft_pbkdf2_sha256(pbkdf_ctx);
ft_des_byte_to_bits(key, FT_DES_BYTE_BLOCK_SIZE, ctx->key,
FT_DES_INITIAL_KEY_SIZE);
write(ctx->output_fd, "Salted__", 8);
write(ctx->output_fd, salt, FT_DES_BYTE_BLOCK_SIZE);
}
void ft_des_derive_key
(
t_des_ctx *ctx
@ -11,6 +73,12 @@ void ft_des_derive_key
t_pbkdf2_sha256_ctx pbkdf_ctx;
t_byte1 key[FT_DES_BYTE_BLOCK_SIZE];
if (!ctx->raw_key && !ctx->raw_salt && !ctx->raw_password)
{
no_arguments(ctx, &pbkdf_ctx);
return ;
}
if (ctx->raw_key)
{
if (ft_des_hex_to_bit(ctx->raw_key, ctx->key, FT_DES_BIT_BLOCK_SIZE))