import six
import timeit#查找任何特定代碼執(zhí)行的確切時間
from ecdsa.curves import curves

#定義do函數(shù)，計算時間
def do(setup_statements, statement):
    # extracted from timeit.py
    t = timeit.Timer(stmt=statement, setup="\n".join(setup_statements))
    # determine number so that 0.2 <= total time < 2.0
    for i in range(1, 10):
        number = 10 ** i #**為次方
        x = t.timeit(number)
        if x >= 0.2:
            break
    return x / number

#不是很懂 sep=":",unit="s",form=".5f",form_inv=".2f",
prnt_form = (
    "{name:>16}{sep:1} {siglen:>6} {keygen:>9{form}}{unit:1} "
    "{keygen_inv:>9{form_inv}} {sign:>9{form}}{unit:1} "
    "{sign_inv:>9{form_inv}} {verify:>9{form}}{unit:1} "
    "{verify_inv:>9{form_inv}} {verify_single:>13{form}}{unit:1} "
    "{verify_single_inv:>14{form_inv}}"
)
print(
    prnt_form.format(
        siglen="siglen",
        keygen="keygen",
        keygen_inv="keygen/s",
        sign="sign",
        sign_inv="sign/s",
        verify="verify",
        verify_inv="verify/s",
        verify_single="no PC verify",
        verify_single_inv="no PC verify/s",
        name="",
        sep="",
        unit="",
        form="",
        form_inv="",
    )
)
for curve in [i.name for i in curves]:
    S1 = "import six; from ecdsa import SigningKey, %s" % curve
    S2 = "sk = SigningKey.generate(%s)" % curve #產(chǎn)生私鑰
    S3 = "msg = six.b('msg')" #消息
    S4 = "sig = sk.sign(msg)" #簽名
    S5 = "vk = sk.get_verifying_key()"#公鑰由私鑰得出  get_verifying_key()函數(shù)
    S6 = "vk.precompute()"#不懂
    S7 = "vk.verify(sig, msg)"#用公鑰驗證簽名
    # 我們碰巧知道.generate()也在計算驗證密鑰，這是最耗時的部分。如果將代碼改為懶惰地計算vk，我們就需要將這個基準改為在S5上循環(huán)，而不是在S2上。
    keygen = do([S1], S2)
    sign = do([S1, S2, S3], S4)
    verf = do([S1, S2, S3, S4, S5, S6], S7)
    verf_single = do([S1, S2, S3, S4, S5], S7)
    import ecdsa
    c = getattr(ecdsa, curve)#從名字上看獲取屬性值
    sig = ecdsa.SigningKey.generate(c).sign(six.b("msg"))
    #密鑰對（keygen）、簽署數(shù)據(jù)（sign）、驗證這些簽名（verify）、共享秘密（ecdh）以及在沒有特定密鑰預計算的情況下驗證簽名（no PC verify）、原始簽名的大?。ㄍǔＪ呛灻梢员痪幋a的最小方式）也在siglen欄中提供
    print(
        prnt_form.format(
            name=curve,#所有的曲線
            sep=":",
            siglen=len(sig),
            unit="s",
            keygen=keygen,
            keygen_inv=1.0 / keygen,
            sign=sign,
            sign_inv=1.0 / sign,
            verify=verf,
            verify_inv=1.0 / verf,
            verify_single=verf_single,
            verify_single_inv=1.0 / verf_single,
            form=".5f",#小數(shù)點后面為5位
            form_inv=".2f",#小數(shù)點后面為2位
        )
    )

print("")

ecdh_form = "{name:>16}{sep:1} {ecdh:>9{form}}{unit:1} {ecdh_inv:>9{form_inv}}"
print(
    ecdh_form.format(
        ecdh="ecdh",
        ecdh_inv="ecdh/s",
        name="",
        sep="",
        unit="",
        form="",
        form_inv="",
    )
)
for curve in [i.name for i in curves]:
    if curve == "Ed25519" or curve == "Ed448":
        continue
    S1 = "from ecdsa import SigningKey, ECDH, {0}".format(curve)
    S2 = "our = SigningKey.generate({0})".format(curve)#私鑰
    S3 = "remote = SigningKey.generate({0}).verifying_key".format(curve)#公鑰
    S4 = "ecdh = ECDH(private_key=our, public_key=remote)"
    S5 = "ecdh.generate_sharedsecret_bytes()"#產(chǎn)生共享密鑰
    ecdh = do([S1, S2, S3, S4], S5)
    print(
        ecdh_form.format(
            name=curve,
            sep=":",
            unit="s",
            form=".5f",
            form_inv=".2f",
            ecdh=ecdh,
            ecdh_inv=1.0 / ecdh,
        )
    )

from ecdsa import SigningKey
sk = SigningKey.generate() # uses NIST192p生成私鑰
vk = sk.verifying_key#在私鑰的基礎上生成公鑰
signature = sk.sign(b"message")#用私鑰對消息進行簽名
assert vk.verify(signature, b"message")#用公鑰去驗證。assert為一斷言函數(shù)：不滿足條件直接觸發(fā)異常忙不執(zhí)行接下來的代碼，括號中為condition

from ecdsa import SigningKey, NIST384p#384位NIST素域橢圓曲線，其中私鑰/公鑰都與特定的曲線相關聯(lián)，更長的曲線更安全，但時間長，密鑰和簽名也長
sk = SigningKey.generate(curve=NIST384p)
vk = sk.verifying_key
signature = sk.sign(b"message")
assert vk.verify(signature, b"message")

#將簽名密鑰（私鑰）序列化成不同的格式。
from ecdsa import SigningKey, NIST384p
sk = SigningKey.generate(curve=NIST384p)
sk_string = sk.to_string()#最短的調(diào)用，然后再重新創(chuàng)建私鑰。to_string()：將括號內(nèi)的數(shù)字轉(zhuǎn)化為字符串，實際返回的類型bytes
sk2 = SigningKey.from_string(sk_string, curve=NIST384p)#重新創(chuàng)建私鑰，第一個參數(shù)是我們要處理的字符，如果點編碼無效或不在指定曲線上，from_string（）將引發(fā)MalformedPointError
print(sk_string.hex())
print(sk2.to_string().hex())

from ecdsa import SigningKey, NIST384p
sk = SigningKey.generate(curve=NIST384p)
sk_pem = sk.to_pem()#sk.to_pem()和sk.to_der()將把簽名密鑰序列化為OpenSSL使用的相同格式
sk2 = SigningKey.from_pem(sk_pem)#SigningKey.from_pem()/.from_der()將撤銷這種序列化。這些格式包括了曲線名稱，所以你不需要向反序列化器傳遞曲線標識符。如果文件是畸形的，from_der()和from_pem()將引發(fā)UnexpectedDER或MalformedPointError。
# sk and sk2 are the same key

from ecdsa import SigningKey, VerifyingKey, NIST384p
sk = SigningKey.generate(curve=NIST384p)
vk = sk.verifying_key
vk_string = vk.to_string()#公鑰可以用同樣的方式進行序列化
vk2 = VerifyingKey.from_string(vk_string, curve=NIST384p)
# vk and vk2 are the same key

from ecdsa import SigningKey, VerifyingKey, NIST384p
sk = SigningKey.generate(curve=NIST384p)
vk = sk.verifying_key
vk_pem = vk.to_pem()
vk2 = VerifyingKey.from_pem(vk_pem)
# vk and vk2 are the same key

import os
from ecdsa import NIST384p, SigningKey
from ecdsa.util import randrange_from_seed__trytryagain#產(chǎn)生隨機數(shù)
def make_key(seed):
  secexp = randrange_from_seed__trytryagain(seed, NIST384p.order)
  return SigningKey.from_secret_exponent(secexp, curve=NIST384p)
seed = os.urandom(NIST384p.baselen) # or other starting point，返回一個適合加密的比特串
sk1a = make_key(seed)
sk1b = make_key(seed)
# note: sk1a and sk1b are the same key
assert sk1a.to_string() == sk1b.to_string()
sk2 = make_key(b"2-"+seed)  # different key  b為比特
assert sk1a.to_string() != sk2.to_string()
from ecdsa import SigningKey, NIST384p
sk = SigningKey.generate(curve=NIST384p)
vk = sk.verifying_key
vk.precompute()
signature = sk.sign(b"message")
assert vk.verify(signature, b"message")

# openssl ecparam -name prime256v1 -genkey -out sk.pem
# openssl ec -in sk.pem -pubout -out vk.pem
# echo "data for signing" > data
# openssl dgst -sha256 -sign sk.pem -out data.sig data
# openssl dgst -sha256 -verify vk.pem -signature data.sig data
# openssl dgst -sha256 -prverify sk.pem -signature data.sig data
#OpenSSL 使用 PEM 文件格式存儲證書和密鑰。PEM 實質(zhì)上是 Base64 編碼的二進制內(nèi)容
import hashlib#
from ecdsa import SigningKey, VerifyingKey
from ecdsa.util import sigencode_der, sigdecode_der#從ecdsa.util寫入和讀取簽名
with open("vk.pem") as f:#公鑰文件
   vk = VerifyingKey.from_pem(f.read())
with open("data", "rb") as f:#open()為讀取模式，with語句直接調(diào)用close方法，r為讀模式，w/wb為寫模式，rb模式打開二進制文件，消息data
   data = f.read()
with open("data.sig", "rb") as f:#消息簽名可讀模式
   signature = f.read()
assert vk.verify(signature, data, hashlib.sha256, sigdecode=sigdecode_der)#公鑰驗證簽名，
with open("sk.pem") as f:#私鑰文件
   sk = SigningKey.from_pem(f.read(), hashlib.sha256)
new_signature = sk.sign_deterministic(data, sigencode=sigencode_der)#用私鑰簽名生成一個新的簽名
with open("data.sig2", "wb") as f:#寫模式
   f.write(new_signature)

# openssl dgst -sha256 -verify vk.pem -signature data.sig2 data
#如果需要與OpenSSL 1.0.0或更早的版本兼容，可以使用ecdsa.util中的sigencode_string和sigdecode_string來分別寫入和讀取簽名。
from ecdsa import SigningKey, VerifyingKey
with open("sk.pem") as f:
    sk = SigningKey.from_pem(f.read())
with open("sk.pem", "wb") as f:
    f.write(sk.to_pem())
with open("vk.pem") as f:
    vk = VerifyingKey.from_pem(f.read())
with open("vk.pem", "wb") as f:
    f.write(vk.to_pem())

#ecdsa.util.PRNG 工具在這里很方便：它需要一個種子并從中產(chǎn)生一個強的偽隨機流。
#os.urandom的函數(shù)作為entropy=參數(shù)來做不同的事情
#ECDSA的簽名生成也需要一個隨機數(shù)，而且每個簽名都必須使用不同的隨機數(shù)（兩次使用相同的數(shù)字會立即暴露出私人簽名密鑰）。
# sk.sign()方法需要一個entropy=參數(shù)，其行為與SigningKey.generate(entropy=)相同。
from ecdsa.util import PRNG
from ecdsa import SigningKey
rng1 = PRNG(b"seed")
sk1 = SigningKey.generate(entropy=rng1)
rng2 = PRNG(b"seed")
sk2 = SigningKey.generate(entropy=rng2)
# sk1 and sk2 are the same key

#如果你調(diào)用SigningKey.sign_deterministic(data)而不是.sign(data)，代碼將生成一個確定性的簽名，而不是隨機的。
# 這使用RFC6979中的算法來安全地生成一個唯一的K值，該值來自于私鑰和被簽名的信息。每次你用相同的密鑰簽署相同的信息時，你將得到相同的簽名（使用相同的k）。
#創(chuàng)建一個NIST521p密鑰對
from ecdsa import SigningKey, NIST521p
sk = SigningKey.generate(curve=NIST521p)
vk = sk.verifying_key
#從一個主種子創(chuàng)建三個獨立的簽名密鑰
from ecdsa import NIST192p, SigningKey
from ecdsa.util import randrange_from_seed__trytryagain
def make_key_from_seed(seed, curve=NIST192p):
    secexp = randrange_from_seed__trytryagain(seed, curve.order)
    return SigningKey.from_secret_exponent(secexp, curve)
sk1 = make_key_from_seed("1:%s" % seed)
sk2 = make_key_from_seed("2:%s" % seed)
sk3 = make_key_from_seed("3:%s" % seed)
#從磁盤上加載一個驗證密鑰，并使用十六進制編碼以未壓縮和壓縮的格式打印出來（在X9.62和SEC1標準中定義）。
from ecdsa import VerifyingKey
with open("public.pem") as f:#加載驗證密鑰
    vk = VerifyingKey.from_pem(f.read())
print("uncompressed: {0}".format(vk.to_string("uncompressed").hex()))
print("compressed: {0}".format(vk.to_string("compressed").hex()))
#從壓縮格式的十六進制字符串中加載驗證密鑰，以未壓縮的格式輸出。
from ecdsa import VerifyingKey, NIST256p
comp_str = '022799c0d0ee09772fdd337d4f28dc155581951d07082fb19a38aa396b67e77759'
vk = VerifyingKey.from_string(bytearray.fromhex(comp_str), curve=NIST256p)
print(vk.to_string("uncompressed").hex())
#與遠程方進行ECDH密鑰交換。
from ecdsa import ECDH, NIST256p
ecdh = ECDH(curve=NIST256p)
ecdh.generate_private_key()
local_public_key = ecdh.get_public_key()
#send `local_public_key` to remote party and receive `remote_public_key` from remote party
with open("remote_public_key.pem") as e:
    remote_public_key = e.read()
ecdh.load_received_public_key_pem(remote_public_key)
secret = ecdh.generate_sharedsecret_bytes()