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openssl-rsa和一些有关pem格式秘钥的一些情报

这种东西不记下来马上就会忘记 openssl下载速度就十分玄学。。。最后要自己配环境变量

openssl-rsa 基本使用

生成rsa密钥对(私钥)

  • 生成2048bit长度
  • 包含 e,d,n,q,p,dp,dq

openssl genrsa -out privkey.pem 2048

提取公钥

  • 包含 n,e openssl rsa -in privkey.pem -pubout -out pubkey.pem

提取csr证书

openssl req -new -key privkey.pem -out ca.csr

提取密钥信息

公私钥模数

openssl rsa -in .\pubkey.pem -pubout -modulus

openssl rsa -in .\pubkey.pem -pubin -modulus

提取所有信息

openssl asn1parse -i -in privkey.pem

公钥要指定偏移查看,bit string的偏移是19

https://i.loli.net/2020/10/12/eCbmTJQY4NkuAv3.png

openssl asn1parse -i -in .\pubkey.pem -strparse 19

pem、der格式转化

openssl rsa -in .\private.pem -outform der -out .\private.der

除了生孩子什么都能干的python

crypto yyds

from Crypto.PublicKey import RSA

读取公钥信息

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rsakey = RSA.importKey(open("public.key", "r").read())
n = rsakey.n
e = rsakey.e
print("n=%\ne=%d",n,e)

生成秘钥对文件

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rsa = RSA.generate(2048)
public_key = rsa.publickey().exportKey()
f = open("public_key.key", "w")
f.write(public_key.decode())
f.close()
private_key = rsa.exportKey()

f = open("private_key.key", "w")
f.write(private_key.decode())
f.close()

对文件加解密

载入编码方式

from Crypto.Cipher import PKCS1_OAEP

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rsakey=RSA.importKey(open("public_key.key","r").read())
rsa = PKCS1_OAEP.new(rsakey)
encrypt = rsa.encrypt(flag.encode())

rsakey=RSA.importKey(open("private_key.key","r").read())
rsa = PKCS1_OAEP.new(rsakey)
decrypt = rsa.decrypt(f.read())

算得 n e d q p 生成 private_key.key

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rsa_components = (n, e, int(d), p, q)
rsa = RSA.construct(rsa_components)
public_key = rsa.exportKey()
# 此rsa与上文随机生成的rsa相同
f = open("public_key.key", "w")
f.write(public_key.decode())
f.close()