def encrypt(M, policy_str):
global Y
global attrs
global sh
global share
global Cr
global Cpr
input = [pk, M, policy_str]
g, g2, h, f, egg = pk
policy = createPolicy(policy_str)
attrs = getAttributeList(policy)
R = groupObj.random(GT)
s = groupObj.hash([R, M], ZR)
s_sesskey = SHA1(R)
Ctl = (R * (egg**s))
sh = calculateSharesDict(s, policy)
Y = len(sh)
C = (h**s)
for y in range(0, Y):
y1 = attrs[y]
share[y1] = sh[y1]
Cr[y1] = (g**share[y1])
Cpr[y1] = (groupObj.hash(y1, G2)**share[y1])
T1 = SymEnc(s_sesskey, M)
ct = [policy_str, Ctl, C, Cr, Cpr, T1]
output = ct
return output
def encrypt(M, id):
global C
global ct
input = [mpk, M, id]
g, gb, ga1, ga2, gba1, gba2, tau1, tau2, tau1b, tau2b, w, u, h, egga = mpk
s1 = groupObj.random(ZR)
R = groupObj.random(GT)
s2 = groupObj.hash([R, M], ZR)
s2_sesskey = SHA1(R)
C[0] = (R * (egga**s2))
t = groupObj.random(ZR)
tag_c = groupObj.random(ZR)
s = (s1 + s2)
id_hash2 = groupObj.hash(id, ZR)
C[1] = (gb**s)
C[2] = (gba1**s1)
C[3] = (ga1**s1)
C[4] = (gba2**s2)
C[5] = (ga2**s2)
C[6] = ((tau1**s1) * (tau2**s2))
C[7] = (((tau1b**s1) * (tau2b**s2)) * (w**-t))
E1 = ((((u**id_hash2) * (w**tag_c)) * h)**t)
E2 = (g**t)
T1 = SymEnc(s2_sesskey, M)
ct = [C, E1, E2, tag_c, T1]
output = ct
def decout(partCT, zz, egg):
input = [partCT, zz, egg]
T0, T1, T2 = partCT
R = (T0 / (T2**zz))
s_sesskey = SHA1(R)
M = SymDec(s_sesskey, T1)
s = groupObj.hash([R, M], ZR)
output = M
return output
def decout(partCT, zz):
T0, T1, T2 = partCT['T0'], partCT['T1'], partCT['T2']
R = (T0 / (T2**zz))
print("Recov R :=", R)
s_sesskey = SHA1(R)
M = SymDec(s_sesskey, T1)
s = groupObj.hash([R, M], ZR)
output = M
return output
def decout(partCT, zz, egga):
input = [partCT, zz, egga]
T0, T1, T2 = partCT
R = (T0 / (T2 ** zz))
s2_sesskey = SHA1(R)
M = SymDec(s2_sesskey, T1)
s2 = groupObj.hash([R, M], ZR)
if ( ( (( (T0) == ((R * (egga ** s2))) )) and (( (T2) == ((R * (egga ** (s2 / zz)))) )) ) ):
output = M
else:
userErrorFunction('invalid ciphertext')
return
return output
def decout(partCT, zz):
input = [partCT, zz, egga]
T0, T1, T2 = partCT
R = (T0 / (T2**zz))
s2_sesskey = SHA1(R)
M = SymDec(s2_sesskey, T1)
print("The message decrypts in decout to: ", M)
s2 = groupObj.hash([R, M], ZR)
if (((((T0) == ((R * (egga**s2)))))
and (((T2) == ((R * (egga**(s2 / zz)))))))):
output = M
print("RCCA check is successful")
else:
output = M
print("RCCA check has failed.")
return output