增加sql的waf功能

resty/sha256.lua

@@ -0,0 +1,69 @@
+-- Copyright (C) by Yichun Zhang (agentzh)
+
+
+require "resty.sha"
+local ffi = require "ffi"
+local ffi_new = ffi.new
+local ffi_str = ffi.string
+local C = ffi.C
+local setmetatable = setmetatable
+--local error = error
+
+
+local _M = { _VERSION = '0.14' }
+
+
+local mt = { __index = _M }
+
+
+ffi.cdef[[
+typedef struct SHA256state_st
+        {
+        SHA_LONG h[8];
+        SHA_LONG Nl,Nh;
+        SHA_LONG data[SHA_LBLOCK];
+        unsigned int num,md_len;
+        } SHA256_CTX;
+
+int SHA256_Init(SHA256_CTX *c);
+int SHA256_Update(SHA256_CTX *c, const void *data, size_t len);
+int SHA256_Final(unsigned char *md, SHA256_CTX *c);
+]]
+
+local digest_len = 32
+
+local buf = ffi_new("char[?]", digest_len)
+local ctx_ptr_type = ffi.typeof("SHA256_CTX[1]")
+
+
+function _M.new(self)
+    local ctx = ffi_new(ctx_ptr_type)
+    if C.SHA256_Init(ctx) == 0 then
+        return nil
+    end
+
+    return setmetatable({ _ctx = ctx }, mt)
+end
+
+
+function _M.update(self, s)
+    return C.SHA256_Update(self._ctx, s, #s) == 1
+end
+
+
+function _M.final(self)
+    if C.SHA256_Final(buf, self._ctx) == 1 then
+        return ffi_str(buf, digest_len)
+    end
+
+    return nil
+end
+
+
+function _M.reset(self)
+    return C.SHA256_Init(self._ctx) == 1
+end
+
+
+return _M
+