def eval_rek():
# for t, n in GLOBAL_VAR_TP_PARAMS:
t, n = 3, 5
tp = tc.ThresholdParameters(t, n)
_, old_shares = tc.create_public_key_and_shares_centralized(GLOBAL_CP, tp)
_, new_shares = tc.create_public_key_and_shares_centralized(GLOBAL_CP, tp)
t_old_shares = old_shares[:t]
t_new_shares = new_shares[:t]
t_old_shares_x = [share.x for share in t_old_shares]
t_new_shares_x = [share.x for share in t_new_shares]
old_lc = [
tc.lagrange_coefficient_for_key_share_indices(t_old_shares_x, s,
GLOBAL_CP)
for s in t_old_shares_x
]
new_lc = [
tc.lagrange_coefficient_for_key_share_indices(t_new_shares_x, s,
GLOBAL_CP)
for s in t_new_shares_x
]
prek = []
for os, olc, ns, nlc in zip(t_old_shares, old_lc, t_new_shares, new_lc):
prek.append(tc.compute_partial_re_encryption_key(os, olc, ns, nlc))
eval_performance("ReEncryptionKeyCombination",
"({}, {})".format(t, n),
tc.combine_partial_re_encryption_keys,
partial_keys=prek,
old_threshold_params=tp,
new_threshold_params=tp)
def eval_reenc(timing_rounds):
tp = tc.ThresholdParameters(5, 10)
old_pub_key, old_shares = tc.create_public_key_and_shares_centralized(
GLOBAL_CP, tp)
new_pub_key, new_shares = tc.create_public_key_and_shares_centralized(
GLOBAL_CP, tp)
t_old_shares = old_shares[:tp.t]
t_new_shares = new_shares[:tp.t]
t_old_shares_x = [share.x for share in t_old_shares]
t_new_shares_x = [share.x for share in t_new_shares]
old_lc = [
tc.lagrange_coefficient_for_key_share_indices(t_old_shares_x, s,
GLOBAL_CP)
for s in t_old_shares_x
]
new_lc = [
tc.lagrange_coefficient_for_key_share_indices(t_new_shares_x, s,
GLOBAL_CP)
for s in t_new_shares_x
]
prek = []
for os, olc, ns, nlc in zip(t_old_shares, old_lc, t_new_shares, new_lc):
prek.append(tc.compute_partial_re_encryption_key(os, olc, ns, nlc))
re_encryption_key = tc.combine_partial_re_encryption_keys(
prek, old_pub_key, new_pub_key, tp, tp)
em = tc.encrypt_message("a", old_pub_key)
eval_performance("ReEncrypt",
"",
tc.re_encrypt_message,
em=em,
re_key=re_encryption_key,
timing_rounds=timing_rounds)
def eval_prek():
tp = tc.ThresholdParameters(5, 10)
_, old_shares = tc.create_public_key_and_shares_centralized(GLOBAL_CP, tp)
_, new_shares = tc.create_public_key_and_shares_centralized(GLOBAL_CP, tp)
t_old_shares_x = [share.x for share in old_shares[:tp.t]]
t_new_shares_x = [share.x for share in new_shares[:tp.t]]
old_lc = tc.lagrange_coefficient_for_key_share_indices(
t_old_shares_x, t_old_shares_x[0], GLOBAL_CP)
new_lc = tc.lagrange_coefficient_for_key_share_indices(
t_new_shares_x, t_new_shares_x[0], GLOBAL_CP)
eval_performance("PartialReEncryptionKey",
"",
tc.compute_partial_re_encryption_key,
old_share=old_shares[0],
old_lc=old_lc,
new_share=new_shares[0],
new_lc=new_lc)
def eval_pd(timing_rounds):
tp = tc.ThresholdParameters(3, 5)
pub_key, shares = tc.create_public_key_and_shares_centralized(
GLOBAL_CP, tp)
em = tc.encrypt_message("a", pub_key)
eval_performance("PartialDecryption",
"",
tc.compute_partial_decryption,
encrypted_message=em,
key_share=shares[0],
timing_rounds=timing_rounds)
def eval_enc(timing_rounds):
tp = tc.ThresholdParameters(3, 5)
pub_key, shares = tc.create_public_key_and_shares_centralized(
GLOBAL_CP, tp)
for msg_size in MESSAGE_BYTE_SIZES:
msg = "a" * msg_size # since encryption uses utf-8 encoding, this leads to messages of size msg_size
eval_performance("Encrypt",
"{}".format(msg_size),
tc.encrypt_message,
message=msg,
public_key=pub_key,
timing_rounds=timing_rounds)
def eval_dec_msg_size(timing_rounds, t=2, n=3):
tp = tc.ThresholdParameters(t, n)
pub_key, shares = tc.create_public_key_and_shares_centralized(
GLOBAL_CP, tp)
for msg_size in MESSAGE_BYTE_SIZES:
msg = "a" * msg_size
enc_msg = tc.encrypt_message(msg, pub_key)
pds = [
tc.compute_partial_decryption(enc_msg, share)
for share in shares[:t]
]
eval_performance("Decrypt" + str(t) + str(n),
"{}".format(msg_size),
tc.decrypt_message,
partial_decryptions=pds,
encrypted_message=enc_msg,
threshold_params=tp,
timing_rounds=timing_rounds)
def eval_dec(timing_rounds):
msg_size = 1024
msg = "a" * msg_size
for (t, n) in GLOBAL_VAR_TP_PARAMS:
tp = tc.ThresholdParameters(t, n)
pub_key, shares = tc.create_public_key_and_shares_centralized(
GLOBAL_CP, tp)
enc_msg = tc.encrypt_message(msg, pub_key)
pds = [
tc.compute_partial_decryption(enc_msg, share)
for share in shares[:t]
]
eval_performance("DecryptCombine",
"({}, {})".format(t, n),
tc.decrypt_message,
partial_decryptions=pds,
encrypted_message=enc_msg,
threshold_params=tp,
timing_rounds=timing_rounds)