SSL證書自簽名使用及監控
阿新 • • 發佈：2019-10-18
前言
證書簡介
資訊保安越來越受重視，HTTPS已經相當普及，要讓我們的HTTP介面支援HTPPS，只需要一個SSL證書就可以啦
- 全稱公鑰證書（Public-Key Certificate, PKC）,裡面儲存著歸屬者的基本資訊，以及證書過期時間、歸屬者的公鑰，並由認證機構（Certification Authority, CA）施加數字簽名，表明，某個認證機構認定該公鑰的確屬於此人
- 自簽名的證書，就是我們來充當 認證機構，這種證書推薦在測試開發過程中，生產環境直接上CA證書省心！
實踐
證書生成
準備
確保有openssl庫
建立目錄
# 根證書目錄 [root@centos7 ~]# mkdir -p /var/ssl/crt/root # 伺服器端證書目錄 [root@centos7 ~]# mkdir -p /var/ssl/crt/server
生成根證書
私鑰，RSA對稱加密，aes比des更安全，金鑰長度2048
openssl genrsa -aes256 -out /var/ssl/crt/root/ca.key -passout pass:"123456" 2048請求流程，包含證書資訊,其中比較關鍵的是CN，是填你的域名，根證書不起服務可以隨便寫，
openssl req -new -key /var/ssl/crt/root/ca.key -out /var/ssl/crt/root/ca.csr -subj "/C=CN/ST=myprovince/L=mycity/O=myorganization/OU=mygroup/CN=www.ca.crt.com/[email protected]" -passin pass:"123456"頒發證書，這個生成的就是可以用的證書了，注意不加v3_ca這個外掛，瀏覽器匯入不了
openssl x509 -req -sha256 -extensions v3_ca -days 3650 -in /var/ssl/crt/root/ca.csr -out /var/ssl/crt/root/ca.crt -signkey /var/ssl/crt/root/ca.key -CAcreateserial -passin pass:"123456"
生成服務端證書
私鑰，RSA對稱加密，aes比des更安全，金鑰長度2048
openssl genrsa -aes256 -out /var/ssl/crt/server/svc1-server.key -passout pass:"123456" 2048請求流程，包含證書資訊,其中比較關鍵的是CN，是填你的域名
openssl req -new -key /var/ssl/crt/server/svc1-server.key -out /var/ssl/crt/server/svc1-server.csr -subj "/C=CN/ST=myprovince/L=mycity/O=myorganization/OU=mygroup/CN=www.svc1.com/[email protected]" -passin pass:"123456"頒發證書，這個生成的就是可以用的證書了，注意不加v3_ca這個外掛，瀏覽器匯入不了
openssl x509 -req -sha256 -extensions v3_req -days 3650 -in /var/ssl/crt/server/svc1-server.csr -out /var/ssl/crt/server/svc1-server.crt -signkey /var/ssl/crt/server/svc1-server.key -CAkey /var/ssl/crt/root/ca.key -CA /var/ssl/crt/root/ca.crt -CAcreateserial -passin pass:"123456"驗證證書
openssl verify -CAfile /var/ssl/crt/root/ca.crt /var/ssl/crt/server/svc1-server.crt
證書使用
Unubtu為例
apt install nginx -y配置
vi /etc/nginx/sites-available/default
# 到最後加上如下內容
server {
listen 443 ssl http2 default_server;
listen [::]:443 ssl http2 default_server;
server_name www.svc1.com;
root /usr/share/nginx/html;
ssl_certificate "/var/ssl/crt/server/svc1-server.crt";
ssl_certificate_key "/var/ssl/crt/server/svc1-server.key";
ssl_session_cache shared:SSL:1m;
ssl_session_timeout 10m;
ssl_ciphers HIGH:!aNULL:!MD5;
ssl_prefer_server_ciphers on;
include /etc/nginx/default.d/*.conf;
location / {
}
error_page 404 /404.html;
location = /40x.html {
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
}
}vi /etc/hosts
127.0.0.1 www.svc1.com啟動
root@CN-00013965:/# sudo service nginx restart
* Restarting nginx nginx Enter PEM pass phrase:
Enter PEM pass phrase: [ OK ]測試
不用證書 失敗
root@CN-00013965:/# wget https://www.svc1.com --2019-10-18 16:37:48-- https://www.svc1.com/ Resolving www.svc1.com (www.svc1.com)... 127.0.0.1 Connecting to www.svc1.com (www.svc1.com)|127.0.0.1|:443... connected. ERROR: cannot verify www.svc1.com's certificate, issued by ‘[email protected],CN=www.ca.crt.com,OU=mygroup,O=myorganization,L=mycity,ST=myprovince,C=CN’: Unable to locally verify the issuer's authority. To connect to www.svc1.com insecurely, use `--no-check-certificate'.用根證書訪問 成功
root@CN-00013965:/# wget --ca-certificate=/var/ssl/crt/root/ca.crt https://www.svc1.com --2019-10-18 16:39:50-- https://www.svc1.com/ Resolving www.svc1.com (www.svc1.com)... 127.0.0.1 Connecting to www.svc1.com (www.svc1.com)|127.0.0.1|:443... connected. HTTP request sent, awaiting response... 200 OK Length: 612 [text/html] Saving to: ‘index.html.1’ index.html.1 100%[===================================================================================================================>] 612 --.-KB/s in 0s 2019-10-18 16:39:50 (32.4 MB/s) - ‘index.html.1’ saved [612/612]
匯入Java應用
java應用要讀取服務端證書需要通過pkcs12格式的keystore檔案，我們可以把不同的服務端證書用別名區分。然後我們讀取trustkeystore去訪問HTTPS其他服務
生成keystore
openssl pkcs12 -export -clcerts -in /var/ssl/crt/server/svc1-server.crt -inkey /var/ssl/crt/server/svc1-server.key -out /var/ssl/crt/server/svc1-server.p12 -name svc1 -passin pass:"123456" -password pass:"123456"keytool命令是JDK自帶的到${JAVA_HOME}/bin下執行，-srcstorepass是我們證書的密碼，其他兩個是keystore的密碼
keytool -importkeystore -trustcacerts -noprompt -deststoretype pkcs12 -srcstoretype pkcs12 -srckeystore /var/ssl/crt/server/svc1-server.p12 -destkeystore /var/ssl/crt/server/svc1-server.keystore -alias svc1 -deststorepass "123456" -destkeypass "123456" -srcstorepass "123456"生成trustkeystore
keytool -import -trustcacerts -noprompt -alias CA -file /var/ssl/crt/root/ca.crt -keystore /var/ssl/crt/root/ca.trustkeystore -storepass "123456"
監控
證書起到服務埠上了，我們怎麼檢視證書資訊，或者實時檢查證書過期資訊呢，已預設443埠為例
root@CN-00013965:/# echo 'Q' | timeout 5 openssl s_client -connect 127.0.0.1:443 2>/dev/null | openssl x509 -noout -subject -dates
subject=C = CN, ST = myprovince, L = mycity, O = myorganization, OU = mygroup, CN = www.svc1.com, emailAddress = [email protected]
notBefore=Oct 18 08:09:32 2019 GMT
notAfter=Oct 15 08:09:32 2029 GMT如果postgresql資料庫起的HTTPS，那麼直接openssl不能直接拿到埠證書，我們可以藉助python指令碼，指令碼是Github上找的
#!/usr/bin/env python
import argparse
import socket
import ssl
import struct
import subprocess
import sys
try:
from urlparse import urlparse
except ImportError:
from urllib.parse import urlparse
def main():
args = get_args()
target = get_target_address_from_args(args)
sock = socket.create_connection(target)
try:
certificate_as_pem = get_certificate_from_socket(sock)
print(certificate_as_pem.decode('utf-8'))
except Exception as exc:
sys.stderr.write('Something failed while fetching certificate: {0}\n'.format(exc))
sys.exit(1)
finally:
sock.close()
def get_args():
parser = argparse.ArgumentParser()
parser.add_argument('database', help='Either an IP address, hostname or URL with host and port')
return parser.parse_args()
def get_target_address_from_args(args):
specified_target = args.database
if '//' not in specified_target:
specified_target = '//' + specified_target
parsed = urlparse(specified_target)
return (parsed.hostname, parsed.port or 5432)
def get_certificate_from_socket(sock):
request_ssl(sock)
ssl_context = get_ssl_context()
sock = ssl_context.wrap_socket(sock)
sock.do_handshake()
certificate_as_der = sock.getpeercert(binary_form=True)
certificate_as_pem = encode_der_as_pem(certificate_as_der)
return certificate_as_pem
def request_ssl(sock):
version_ssl = postgres_protocol_version_to_binary(1234, 5679)
length = struct.pack('!I', 8)
packet = length + version_ssl
sock.sendall(packet)
data = read_n_bytes_from_socket(sock, 1)
if data != b'S':
raise Exception('Backend does not support TLS')
def get_ssl_context():
for proto in ('PROTOCOL_TLSv1_2', 'PROTOCOL_TLSv1', 'PROTOCOL_SSLv23'):
protocol = getattr(ssl, proto, None)
if protocol:
break
return ssl.SSLContext(protocol)
def encode_der_as_pem(cert):
cmd = ['openssl', 'x509', '-inform', 'DER']
pipe = subprocess.PIPE
process = subprocess.Popen(cmd, stdin=pipe, stdout=pipe, stderr=pipe)
stdout, stderr = process.communicate(cert)
if stderr:
raise Exception('OpenSSL error when converting cert to PEM: {0}'.format(stderr))
return stdout.strip()
def read_n_bytes_from_socket(sock, n):
buf = bytearray(n)
view = memoryview(buf)
while n:
nbytes = sock.recv_into(view, n)
view = view[nbytes:] # slicing views is cheap
n -= nbytes
return buf
def postgres_protocol_version_to_binary(major, minor):
return struct.pack('!I', major << 16 | minor)
if __name__ == '__main__':
main()使用方法：如果python檔名叫get_postgres_cert.py
python get_postgres_cert.py 127.0.0.1:5432