def decrypt(file, save_as, schema, base_path):
if schema == 'AES':
pickle_in = open(base_path + 'en-de/aes.p', 'rb')
passwd = pickle.load(pickle_in)
pickle_in.close()
AES.decrypt_AES(file, passwd, save_as)
elif schema == 'RSA':
pickle_in = open(base_path + 'en-de/rsa.p', 'rb')
code = pickle.load(pickle_in)
pickle_in.close()
RSA.decrypt_RSA(file, code, save_as, base_path)
elif schema == 'DES':
pickle_in = open(base_path + 'en-de/des.p', 'rb')
passwd = pickle.load(pickle_in)
pickle_in.close()
DES.decrypt_DES(file, passwd, save_as)
elif schema == 'BF':
pickle_in = open(base_path + 'en-de/bf.p', 'rb')
passwd = pickle.load(pickle_in)
pickle_in.close()
bf.decrypt_bf(file, passwd, save_as)
else:
print('pending')
sys.exit(2)
def incremental_update_genrate_hash(key_tag, tag,
indices_to_update_list_sorted,
original_message_list,
updated_messages_list_ac_indices):
### TAG IS OF STR TYPE
### 2nd argument should be str type
h = DES.decrypt_DES(key_tag, tag)
print("From em module line 56 h we have decrypted", h)
h = int(h, 16)
R = randomize_blocks(original_message_list)
R_new = randomize_blocks(updated_messages_list_ac_indices)
### str type
N = len(R)
#visited =[0]*N
nb = len(indices_to_update_list_sorted)
for i in range(nb):
j = indices_to_update_list_sorted[i]
if (j != 0 & j != N - 1):
h = h ^ f1(hex(int(R[j], 2))[2:], R[j + 1]) ^ f1(
hex(int(R[j - 1], 2))[2:], R[j])
R[j] = R_new[i]
h = h ^ f1(hex(int(R[j], 2))[2:], R[j + 1]) ^ f1(
hex(int(R[j - 1], 2))[2:], R[j])
if (j == 0):
h = h ^ f1(hex(int(R[0], 2))[2:], R[1]) ^ f1(
hex(int(R[N - 1], 2))[2:], R[0])
R[j] = R_new[i]
h = h ^ f1(hex(int(R[0], 2))[2:], R[1]) ^ f1(
hex(int(R[N - 1], 2))[2:], R[0])
if (j == N - 1):
h = h ^ f1(hex(int(R[N - 2], 2))[2:], R[N - 1]) ^ f1(
hex(int(R[N - 1], 2))[2:], R[0])
R[j] = R_new[i]
h = h ^ f1(hex(int(R[N - 2], 2))[2:], R[N - 1]) ^ f1(
hex(int(R[N - 1], 2))[2:], R[0])
tag_updated = DES.encrypt_DES(key_tag, hex(h))
return tag_updated, hex(h)
