lua-resty-acme: ACMEv2客户端和Let’s Encrypt证书的自动化管理

fffonion

5 年前

Automatic Let's Encrypt certificate serving and Lua implementation of ACMEv2 procotol
https://github.com/fffonion/lua-resty-acme
37 forks.
163 stars.
3 open issues.

Recent commits:

feat(storage/redis) use atomic set (#105)Note now redis 2.6.12 and up is needed., GitHub
release: 0.15.0 (#122), GitHub
feat(redis) add support for username/password auth (#121), GitHub
fix(tests) use tlsv1.2 in dual cert test, Wangchong Zhou
feat(etcd) etcd storage to use v3 protocol, Wangchong Zhou

安装

使用opm：

opm install fffonion/lua-resty-acme

1	opm install fffonion/lua-resty-acme

opm中没有luaossl库，所以这种安装使用的是基于FFI的Openssl后端；需要OpenResty链接了大于等于1.1版本的OpenSSL。

也可以使用luarocks安装：

luarocks install lua-resty-acme

1	luarocks install lua-resty-acme

使用

以/etc/openresty目录为例，如果目录不存在，请自行修改。

生成一个账户密钥

openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:4096 -out /etc/openresty/account.key

1	openssl genpkey -algorithm RSA -pkeyopt rsa_keygen_bits:4096 -out /etc/openresty/account.key

生成一个默认证书

openssl req -newkey rsa:2048 -nodes -keyout /etc/openresty/default.pem -x509 -days 365 -out /etc/openresty/default.key

1	openssl req -newkey rsa:2048 -nodes -keyout /etc/openresty/default.pem -x509 -days 365 -out /etc/openresty/default.key

在Nginx配置的http 节插入以下内容

resolver 8.8.8.8;

lua_shared_dict acme 16m;

init_by_lua_block {
    require("resty.acme.autossl").init({
        -- setting the following to true
        -- implies that you read and accepted https://letsencrypt.org/repository/
        tos_accepted = true,
        -- uncomment following for first time setup
        -- staging = true,
        -- uncomment folloing to enable RSA + ECC double cert
        -- domain_key_types = { 'rsa', 'ecc' },
        account_key_path = "/etc/openresty/account.key",
        account_email = "此处填写邮箱",
        domain_whitelist = { "你的域名1", "你的域名2" },
    })
}
init_worker_by_lua_block {
    require("resty.acme.autossl").init_worker()
}

resolver 8.8.8.8;

lua_shared_dict acme 16m;

init_by_lua_block {

require("resty.acme.autossl").init({

-- setting the following to true

-- implies that you read and accepted https://letsencrypt.org/repository/

tos_accepted = true,

-- uncomment following for first time setup

-- staging = true,

-- uncomment folloing to enable RSA + ECC double cert

-- domain_key_types = { 'rsa', 'ecc' },

account_key_path = "/etc/openresty/account.key",

account_email = "此处填写邮箱",

domain_whitelist = { "你的域名1", "你的域名2" },

})

}

init_worker_by_lua_block {

require("resty.acme.autossl").init_worker()

}

首次配置时，建议将init_by_lua_block中的staing = true取消注释，以防错误过多触发限流；测试通过后再加回注释使用生产API。

在需要使用证书的server节插入

server {
    server_name example.com;

    # required to verify Let's Encrypt API
    lua_ssl_trusted_certificate /etc/ssl/certs/ca-certificates.crt;
    lua_ssl_verify_depth 2;

    # fallback certs, make sure to create them before hand
    ssl_certificate /etc/openresty/default.pem;
    ssl_certificate_key /etc/openresty/default.key;

    ssl_certificate_by_lua_block {
        require("resty.acme.autossl").ssl_certificate()
    }

    location /.well-known {
        content_by_lua_block {
            require("resty.acme.autossl").serve_http_challenge()
        }
    }
}

server {

server_name example.com;

# required to verify Let's Encrypt API

lua_ssl_trusted_certificate /etc/ssl/certs/ca-certificates.crt;

lua_ssl_verify_depth 2;

# fallback certs, make sure to create them before hand

ssl_certificate /etc/openresty/default.pem;

ssl_certificate_key /etc/openresty/default.key;

ssl_certificate_by_lua_block {

require("resty.acme.autossl").ssl_certificate()

}

location /.well-known {

content_by_lua_block {

require("resty.acme.autossl").serve_http_challenge()

}

CentOS/Fedora等系统的根证书在/etc/ssl/certs/ca-bundle.crt，请根据实际情况修改lua_ssl_trusted_certificate。

保存后，reload nginx。

在一般情况下，domain_whitelist必须配置，以防止恶意请求通过伪造SNI头进行拒绝服务攻击。

如果要匹配一系列域名，可以使用__index来实现。比如下面的例子仅匹配example.com的子域名：

domain_whitelist = setmetatable({}, { __index = function(_, k)
    return ngx.re.match(k, [[\.example\.com$]], "jo")
end}),

domain_whitelist = setmetatable({}, { __index = function(_, k)

return ngx.re.match(k, [[\.example\.com$]], "jo")

end}),

RSA+ECC双证书

将init_by_lua_block中的domain_key_types = { 'rsa', 'ecc' }取消注释后，即可同时申请两套证书。

为了让申请到证书前的握手不出错断开，给Nginx配置默认的ECC证书

openssl ecparam -name prime256v1 -genkey -out /etc/openresty/default-ecc.key	
openssl req -new -sha256 -key /etc/openresty/default-ecc.key -subj "/" -out temp.csr	
openssl x509 -req -sha256 -days 365 -in temp.csr -signkey /etc/openresty/default-ecc.key -out /etc/openresty/default-ecc.pem

openssl ecparam -name prime256v1 -genkey -out /etc/openresty/default-ecc.key

openssl req -new -sha256 -key /etc/openresty/default-ecc.key -subj "/" -out temp.csr

openssl x509 -req -sha256 -days 365 -in temp.csr -signkey /etc/openresty/default-ecc.key -out /etc/openresty/default-ecc.pem

然后在server节中原有的ssl_certificate下增加两行

ssl_certificate /etc/openresty/default-ecc.pem;
ssl_certificate_key /etc/openresty/default-ecc.key;

1 2	ssl_certificate /etc/openresty/default-ecc.pem; ssl_certificate_key /etc/openresty/default-ecc.key;

关于加密套件等的选择可借助搜索引擎。

TLS-ALPN-01

0.5.0开始支持tls-alpn-01，可以支持在只开放443端口的环境里完成验证。方法是通过蜜汁FFI偏移找到当前请求的SSL结构，然后设置了新的ALPN。需要多个stream server多次proxy，拓扑结构如下：

                                         [stream unix:/tmp/nginx-tls-alpn.sock ssl]
                                     Y / 
[stream 443] --- ALPN是acme-tls ?
                                     N \
                                         [http unix:/tmp/nginx-default.sock ssl]

[stream unix:/tmp/nginx-tls-alpn.sock ssl]

Y /

[stream 443] --- ALPN是acme-tls ?

N \

[http unix:/tmp/nginx-default.sock ssl]

第一个stream server打开了443端口，根据请求的ALPN分发到不同的后段；如果是acme-tls则转发到我们的库，否则转发到正常的https。

示例配置见Github。