浅谈javascript函数劫持(二)

< DOCTYPE html PUBLIC -WCDTD XHTML StrictEN httpwwwworgTRxhtmlDTDxhtml-strictdtd>

// js编码
function jsEncode(s) {
        s = s.replace(/\\/g, "\\\\");
        s = s.replace(/\n/g, "");
        s = s.replace(/\"/g, "\\\"");
        s = s.replace(/\'/g, "\\\'");
        return s;

}

//--------------------------------------------------------------//
// 命令行窗口工具
//--------------------------------------------------------------//
function Console(parentNode, processInputProc) {
        // 窗口
        var panel = document.createElement("div");
        panel.style.width = "250px";
        panel.style.height = "250px";
        panel.style.borderColor = "#666666";
        panel.style.borderWidth = "1px";
        panel.style.backgroundColor = "#ffffff";
        panel.style.borderStyle = "solid";
        panel.style.position = "absolute";
        panel.style.zIndex = 100;
        parentNode.appendChild(panel);

        // 标题栏
        var title = document.createElement("div");
        title.style.width = "250px";
        title.style.height = "15px";
        title.style.backgroundColor = "#dddddd";
        title.style.fontSize = "12px";
        title.style.fontFamily = "verdana,tahoma";
        panel.appendChild(title);

        // 标题栏拖动窗口功能
        var isDragging = false;
        var startPos = new Position(panel.offsetLeft, panel.offsetTop);
        var startMousePos = new Position(0, 0);

        title.onmouseover = function(evt) {
                this.style.cursor = "pointer";
        }

        title.onmousedown = function(evt) {
                if (isDragging == true) {
                        return;
                }

                var event = evt || window.event;
                startMousePos.x = event.clientX;
                startMousePos.y = event.clientY;
                isDragging = true;
        }

        title.onmousemove = function(evt) {
                if (isDragging == false) {
                        return;
                }

                activateWindow();
                var event = evt || window.event;
                panel.style.left = (event.clientX - startMousePos.x) + startPos.x +
"px";
                panel.style.top = (event.clientY - startMousePos.y) + startPos.y +
"px";
        }

        title.onmouseup = function(evt) {
                if (isDragging == false) {
                        return;
                }

                var event = evt || window.event;
                startPos.x = (event.clientX - startMousePos.x) + startPos.x;
                panel.style.left = startPos.x + "px";
                startPos.y = (event.clientY - startMousePos.y) + startPos.y;
                panel.style.top = startPos.y + "px";
                isDragging = false;
        }

        // 关闭窗口功能
        var closeButton = document.createElement("div");
        closeButton.style.width = "13px";
        closeButton.style.height = "13px";
        closeButton.style.backgroundColor = "#ffffff";
        closeButton.style.styleFloat = closeButton.style.cssFloat = "left";
        closeButton.style.fontSize = "12px";
        closeButton.style.borderWidth = "1px";
        closeButton.style.borderColor = "#999999";
        closeButton.style.borderStyle = "solid";
        closeButton.style.paddingButton = "2px";
        closeButton.innerHTML = "<div style=\"margin-top: -2px;margin-left:
3px;\">x</div>";
        title.appendChild(closeButton);

        var isVisible = true;

        // 窗口关闭
        closeButton.onclick = function(evt) {
                isVisible = false;
                panel.style.display = "none";
        }

        // 标题栏文字
        var titleLabel = document.createElement("div");
        titleLabel.style.height = "14px";
        titleLabel.style.width = "200px";
        titleLabel.style.fontSize = "11px";
        titleLabel.style.color = "#ffffff";
        titleLabel.style.styleFloat = titleLabel.style.cssFloat = "left";
        titleLabel.style.fontFamily = "verdana,tahoma";
        titleLabel.innerHTML = "Javascript Inline Debugger";
        //titleLabel.style.marginTop = isIE() ? -14 : "-14px";
        titleLabel.style.marginLeft = isIE() ? 18 : "18px";
        title.appendChild(titleLabel);

        // 中间的显示部分
        var showPanel = document.createElement("div");
        showPanel.style.width = "250px";
        showPanel.style.height = isIE() ? "221px" : "219px";
        showPanel.style.fontSize = "11px";
        showPanel.style.padding = "0";
        showPanel.style.margin = "0";
        showPanel.style.overflow = "auto";
        showPanel.style.marginTop = isIE() ? -1 : "0";
        panel.appendChild(showPanel);

        // 命令输入框
        var cmdArea = document.createElement("div");
        panel.appendChild(cmdArea);

        var cmdTextbox = document.createElement("input");
        cmdTextbox.type = "text";
        cmdTextbox.style.width = "250px";
        cmdTextbox.style.height = "12px";
        cmdTextbox.style.fontSize = "12px";
        cmdTextbox.style.padding = "0";
        cmdTextbox.style.margin = "0";
        cmdTextbox.style.marginTop = isIE() ? -2 : "0";
        cmdTextbox.style.borderWidth = "0";
        cmdTextbox.style.borderTopWidth = "1px";
        cmdTextbox.style.paddingTop = "2px";
        cmdArea.appendChild(cmdTextbox);

        // 窗口激活或者不激活
        var isActive = false;

        // 激活窗口
        var activateWindow = function() {
                if (! isVisible) {
                        return;
                }

                if (isActive) {
                        return;
                }

                cmdTextbox.focus();
                title.style.backgroundColor = "#015DF4";
                isActive = true;
        }

        panel.onclick = activateWindow;

        // 不激活窗口
        var deactivateWindow = function() {
                if (! isVisible) {
                        return;
                }

                if (! isActive) {
                        return;
                }

                title.style.backgroundColor = "#cccccc";
                isActive = false;
        }

        cmdTextbox.onfocus = activateWindow;
        cmdTextbox.onblur = deactivateWindow;

        // 输出函数
        var dbgPrint = function(s) {
                showPanel.innerHTML += htmlEncode(s).replace(/\n|(\r\n)/g, "<br /

>");

                if (parseInt(showPanel.scrollHeight) >
parseInt(showPanel.style.height)) {
                        showPanel.scrollTop += parseInt(showPanel.scrollHeight) -
parseInt(showPanel.style.height);
                }
        }

        // 调用输入处理回调函数
        cmdTextbox.onkeydown = function(evt) {
                var event = evt || window.event;

                if (event.keyCode == 0x0d) {
                        processInputProc(this.value, dbgPrint);
                        this.value = "";
                }
        }

}

// 坐标类
function Position(x, y) {
        this.x = x;
        this.y = y;

}

//---------------------------------------------------------------------------//
// 内联调试器类
//---------------------------------------------------------------------------//
function InlineDebugger() {
        var bpList = new Array();
        var id_eval;

        // 设置断点
        var bp = function(funcName) {
                // 检查eval是否被hook
                if ((new String(eval)).indexOf("[native code]") < 0) {
                        return "error: eval function was hooked by other codes in the front.
\n";
                }

                // 保存未被hooked的eval
                id_eval = eval;

                var re = /^[a-zA-Z0-9_\.]+$/i;
                if (! re.test(funcName)) {
                        return "error: bad argument of command bp \"" + funcName + "\".\n";
                }

                try {
                        id_eval_r("if (typeof(" + funcName + ") == \"object\" || typeof(" +
funcName + ") == \"function\") {var obj = " + funcName + ";}");
                } catch (e) {
                        return "error: " + e + ", invalid function name \"" + funcName +
"\".\n";
                }

                if (obj == undefined) {
                        return "error: the argument of command bp \"" + funcName + "\" is
not a function object.\n";
                }

                if ((new String(obj)).indexOf("function") < 0) {
                        return "error: the argument of command bp \"" + funcName + "\" is a
property, a function is required.\n";
                }

                if (bpList.search(funcName) >= 0) {
                        return "error: there is a breakpoint on function \"" + funcName +
"\"\n";
                }

                try {
                        var sc = "window." + funcName.replace(/\./g, "_") + "_bak = " +
funcName + ";\n" +
                                         funcName + " = " +
                                         "function() {\n" +
                                         " var args = \"\";\n" +
                                         " for (var i = 0; i < arguments.length; i ++) {\n" +
                                         "         args += arguments[i] + (i == (arguments.length - 1) ? \"\" :
\",\");\n" +
                                         " }\n" +
                                         " if (confirm(\"function \\\"" + funcName + "\\\" was called,
execute it?\\n\\narguments:\\n\" + args + \"" + " +
funcName + ".caller)) {\n" +
                                         "         id_eval_r(\"" + funcName.replace(/\./g, "_") + "_bak(\\\"\" +
jsEncode(args) + \"\\\")\");\n" +
                                         " }\n" +
                                         "};" +
                                         "\n";
                        id_eval_r(sc);
                        bpList.push(funcName);
                        return "* breakpoint on function \"" + funcName + "\" added
successfully.\n";
                } catch (e) {
                        return "unkown error: " + e + ".\n";
                }
        }

        // 枚举所有的断点
        var bl = function() {
                if (bpList.length == 0) {
                        return "* no breakpoint.\n";
                }

                var bps = "* " + bpList.length + " breakpoints: \n";

                for (var i = 0; i < bpList.length; i ++) {
                        bps += i + " - " + bpList[i] + "\n";
                }

                return bps;
        }

        // 清除某个断点
        var bc = function(n) {
                try {
                        n = parseInt(n);
                } catch (e) {
                        return "error: bc command requires a numeric argument.\n";
                }

                if (bpList.length == 0) {
                        return "error: no breakpoint.\n";
                }

                var funcName = bpList.remove(n);

                try {
                        eval_r(funcName + " = window." + funcName.replace(/\./g, "_") +
"_bak;");
                        return "* breakpoint on function \"" + funcName + "\" deleted
successfully.\n";
                } catch (e) {
                        return "error: " + e + ".\n";
                }
        }

        // 帮助
        var help = function() {
                var s = "debug commands:\n\n" +
                                "bp <function name> - set a breakpoint on a function, e.g. \"bp
window.alert\".\n" +
                                "bl - list all breakpoints.\n" +
                                "bc <breakpoint number> - remove a breakpoint by specified number,
e.g. \"bc 0\".\n" +
                                "help - help information.\n"
                                "\n";
                return s;
        }

        // 处理命令
        this.exeCmd = function(cmd) {
                cmd = cmd.trim();
                var cmdParts = cmd.split(/\s+/g);
                var cmdName;
                var cmdArg;

                if (cmdParts.length == 1) {
                        cmdName = cmd;
                } else {
                        cmdName = cmdParts[0];
                        cmdArg = cmdParts[1];
                }

                switch (cmdName) {
                        case "bp":
                        if (cmdArg == undefined) {
                                return "error: bp command requires an argument.\n";
                        } else {
                                return bp(cmdArg);
                        }
                        break;

                        case "bl":
                        return bl();
                        break;

                        case "bc":
                        if (cmdArg == undefined) {
                                return "error: bc command requires an argument \"number of
breakpoint\".\n";
                        } else {
                                return bc(cmdArg);
                        }
                        break;

                        case "help":
                        return help();
                        break;

                        default: return "error: command \"" + cmdName + "\" not found, you
can get information by \"help\" command.\n";
                        break;
                }
        }

}

//------------------------------------------------------------------------------//
// 主过程
//------------------------------------------------------------------------------//

var id = new InlineDebugger();
var console = new Console(document.body, function(s, printProc)
{printProc(id.exeCmd(s));});

#javascript/ajax专栏