如何验证openssl创建的pycrypto签名？

Question

我已经在 openssl 中创建了私钥/公钥，并签署了一些数据：

openssl genrsa -out private.pem 1024
openssl rsa -in private.pem -out public.pem -outform PEM -pubout
echo 'data to sign' > data.txt
openssl dgst -md5 < data.txt > hash
openssl rsautl -sign -inkey private.pem -keyform PEM -in hash  > signature

现在在 python 中，我正在尝试验证此数据：

pubKey = open('public.pem').read()
data = open('data.txt').read()
signature = open('signature').read()

from Crypto import PublicKey
key = PublicKey.RSA.importKey(pubKey)
pub = key.publickey()
hash = MD5.new(data).hexdigest()
# here, hash is same, as contents of 'hash' file
print pub.verify(hash, signature) # <-- here

问题是， pub.verify 期望第二个参数为 1 - 数量较大的元素列表。而且我不知道如何将文件 signature 中的二进制数据转换为这个整数。关于 pycrypto 的每个示例都显示从 pycrypto 生成的签名，并且 key.sign() 生成格式为 (1832273432...2340234L, ) 的正确签名。但我不知道如何使用外部签名。

如果有必要，下面是我不知道如何解释的附加信息：

简要技术信息：

• 数字签名格式： PKCS#7“签名数据”
• 公钥程序： DSS
• 密钥长度： 512 – 1024 位
• 公开指数：2+1
• 公开密钥格式：X.509 v3 证书
• MD（消息摘要）算法：MD5 或 RIPEMD-160 16

Answer 1

Crypto.Signature 模块就是您想要的。来自 Crypto.Signature.PKCS1_v1_5 文档：

key = RSA.importKey(open('pubkey.der').read())
h = SHA.new(message)
verifier = PKCS1_v1_5.new(key)
if verifier.verify(h, signature):
   print "The signature is authentic."
else:
   print "The signature is not authentic."

Answer 2

我遇到了同样的问题，这里有两个示例，使用 openssl 和 python 生成和验证。希望这对某人有帮助...

Bash：

#!/bin/bash
# Generate keys
openssl genrsa -out priv.pem
# Export public key
openssl rsa -pubout -in priv.pem -out pub.pem
# Create test file
echo test123 > test.txt
# Create SHA1 signature
openssl dgst -sha1 -sign priv.pem -out test.txt.sig test.txt
# Verify SHA1 signature
openssl dgst -sha1 -verify pub.pem -signature test.txt.sig test.txt

Python：

#!/usr/bin/python
from Crypto.Signature import PKCS1_v1_5
from Crypto.PublicKey import RSA
from Crypto.Hash import SHA
from Crypto import Random
# Read public key from file
fd = open('pub.pem', 'r')
key_data = fd.read()
fd.close()
# Load public key
key = RSA.importKey(key_data)
# Read test file
fd = open('test.txt', 'r')
message = fd.read()
fd.close()
# Create SHA1 hash object
h = SHA.new(message)
# Create PKCS1 handler
cipher = PKCS1_v1_5.new(key)
# Read signature file
fd = open('test.txt.sig', 'r')
signature = fd.read()
fd.close()
# Verify signature
print cipher.verify(h, signature)
# Read private key from file
fd = open('priv.pem', 'r')
priv_key_data = fd.read()
fd.close()
# Load private key
priv_key = RSA.importKey(priv_key_data)
# Create PKCS1 handler
priv_cipher = PKCS1_v1_5.new(priv_key)
# Sign hash of test file content and compare
signature2 = priv_cipher.sign(h)
if signature == signature2:
    print "Match!! :)"

经过更多阅读后我学到了（https://en .wikipedia.org/wiki/PKCS_1）认为 PKCS1_PSS 是应该用于创建签名的新方案。

两个脚本都需要一些更改：

Bash：

#!/bin/bash
# Generate keys
openssl genrsa -out priv.pem
# Export public key
openssl rsa -pubout -in priv.pem -out pub.pem
# Create test file
echo test123 > test.txt
# Create SHA1 signature
openssl dgst -sha1 -sigopt rsa_padding_mode:pss -sigopt rsa_pss_saltlen:-1 -sign priv.pem -out test.txt.sig test.txt
# Verify SHA1 signature
openssl dgst -sha1 -sigopt rsa_padding_mode:pss -sigopt rsa_pss_saltlen:-1 -verify pub.pem -signature test.txt.sig test.txt

Python：

#!/usr/bin/python
from Crypto.Signature import PKCS1_PSS
from Crypto.PublicKey import RSA
from Crypto.Hash import SHA
from Crypto import Random
# Read public key from file
fd = open('pub.pem', 'r')
key_data = fd.read()
fd.close()
# Load public key
key = RSA.importKey(key_data)
# Read test file
fd = open('test.txt', 'r')
message = fd.read()
fd.close()
# Create SHA1 hash object
h = SHA.new(message)
# Create PKCS1 handler
cipher = PKCS1_PSS.new(key)
# Read signature file
fd = open('test.txt.sig', 'r')
signature = fd.read()
fd.close()
# Verify signature
print cipher.verify(h, signature)
# Read private key from file
fd = open('priv.pem', 'r')
priv_key_data = fd.read()
fd.close()
# Load private key
priv_key = RSA.importKey(priv_key_data)
# Create PKCS1 handler
priv_cipher = PKCS1_PSS.new(priv_key)
# Sign hash of test file content and compare
signature2 = priv_cipher.sign(h)
# PKCS1_PSS signatures always differ!
#if signature == signature2:
#    print "Match!! :)"

Answer 3

这是解决方案。

from Crypto.Util import number
signature  = number.bytes_to_long(signature) #Convert the signature to long
print pub.verify(hash, (signature,) ) #Pass tuple to verify

Answer 4

这篇文章给你最好的答案。
如何在 Python 中验证 RSA SHA1 签名？< /a>

pycrypto 无法验证 OpenSSL 创建的签名。您可以尝试 M2Crypto。