鉴于网上很难找全相应的Lua工具，或者难用的要死，因此创建本项目；
基于openssl，实现常用的加密、摘要算法的Lua工具包，如hmac, md5, aes, rsa等，具体功能参见示例代码；
我是基于LuaJIT-2.0.3和openssl 1.0.0编译的，可以根据你的环境改codec.c的include以及Makefile；
cd src/
make
mv codec.so $YOUR_LUA_PACKAGE_PATH（如：/usr/local/lib/lua/5.1）
local codec = require('codec')
local src = '123456'
local dst = codec.base64_encode(src)
print(dst)
local dsrc = codec.base64_decode(dst)
print(dsrc)
assert(dsrc == src)
local codec = require('codec')
local src = '123456'
local dst = codec.md5_encode(src)
print(dst)
assert('e10adc3949ba59abbe56e057f20f883e' == dst)
local codec = require('codec')
local src = '123456'
local dst = codec.hmac_sha1_encode(src)
print(dst)
assert('06285a0e4a99a56f7f9d1e239acad4de7c79ebe9' == dst)
local codec = require('codec')
local src, key = '123456', '0123456789abcdef'
local bs = codec.aes_encrypt(src, key)
local dst = codec.base64_encode(bs)
print(dst)
local dbs = codec.base64_decode(dst)
local dsrc = codec.aes_decrypt(dbs, key)
print(dsrc)
assert(dsrc == src)
local codec = require('codec')
local src = '123456'
local privpem = [[-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----]]
local bs = codec.rsa_private_sign(src, privpem)
local sign = codec.base64_encode(bs)
print(sign)
local dbs = codec.base64_decode(sign)
local pubpem = [[-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCsxjKD2lnmkmELoo5QphM/VdRE
JKym26R0T+19JDa3MVZFDbwgUGT8XM8bElrKgxexhTVRt07btyIejdbiPx7sCbWc
VP8peZI+QZEVVzaE2Ci5n0lP9v9GUSl0QfZU94uIwl++BVq0VFvbHax/R/q4oTRD
1u73ASM27QW42+cJFwIDAQAB
-----END PUBLIC KEY-----]]
local typ = 2
local ok = codec.rsa_public_verify(src, dbs, pubpem, typ)
assert(ok)
rsa_public_verify最后一个参数为公钥串类型，1：PEM 2：PKCS8 就是“-----BEGIN RSA PUBLIC KEY-----”和“-----BEGIN PUBLIC KEY-----”的区别，啦啦啦
local codec = require('codec')
local src = '123456'
local pubpem = [[-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCsxjKD2lnmkmELoo5QphM/VdRE
JKym26R0T+19JDa3MVZFDbwgUGT8XM8bElrKgxexhTVRt07btyIejdbiPx7sCbWc
VP8peZI+QZEVVzaE2Ci5n0lP9v9GUSl0QfZU94uIwl++BVq0VFvbHax/R/q4oTRD
1u73ASM27QW42+cJFwIDAQAB
-----END PUBLIC KEY-----]]
local typ = 2
local bs = codec.rsa_public_encrypt(src, pubpem, typ)
local dst = codec.base64_encode(bs)
print(dst)
local privpem = [[-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----]]
local dbs = codec.base64_decode(dst)
local dsrc = codec.rsa_private_decrypt(dbs, privpem)
print(dsrc)
assert(dsrc == src)
rsa_public_encrypt最后一个参数为公钥串类型，1：PEM 2：PKCS8 就是“-----BEGIN RSA PUBLIC KEY-----”和“-----BEGIN PUBLIC KEY-----”的区别，再啦啦啦