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Password Management:Hardcoded Password 密码管理：硬编码密码

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Abstract: Hardcoded password 可能会危及系统安全性，并且无法轻易修正出现的安全问题。 Explanation: 使用硬编码方式处理密码绝非好方法。这不仅是因为所有项目开发人员都可以使用通过硬编码方式处理的密码，而且还会使解决这一问题变得极其困难。一旦代码投入使用，除非对软件进行修补，否则您再也不能改变密码了。如果帐户中的密码保护减弱，系统所有者将被迫在安全性和可行性之间做出选择。示例：以下代码使用 hardcoded password 来连接应用程序和检索地址簿条目： ... obj = new XMLHttpRequest(); obj.open('GET','/fetchusers.jsp?id='+form.id.value,'true','scott','tiger'); ... 该代码会正常运行，但是任何能够访问其中所包含的网页的人都能得到这个密码。 Instance ID: 847A3E3204A25FCA6A424B6AB801BC03 Priority Metadata Values: IMPACT: 4.0 LIKELIHOOD: 3.2 Legacy Priority Metadata Values: SEVERITY: 4.0 CONFIDENCE: 5.0 Remediation Effort: 3.0 ------------

Dynamic Code Evaluation:Code Injection 动态代码评估：代码注入

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Abstract: ext-all-debug.js 文件将未验证的用户输入解析为第 11304 行的源代码。在运行时中解析用户控制的指令，会让攻击者有机会执行恶意代码。 Explanation: 许多现代编程语言都允许动态解析源代码指令。这使得程序员可以执行基于用户输入的动态指令。当程序员错误地认为由用户直接提供的指令仅会执行一些无害的操作时（如对当前的用户对象进行简单的计算或修改用户的状态），就会出现 code injection 漏洞：然而，若不经过适当的验证，用户指定的操作可能并不是程序员最初所期望的。示例：在这一典型的代码注入示例中，应用程序实施的基本计算器允许用户指定要执行的命令。 ... userOp = form.operation.value; calcResult = eval(userOp); ... 如果 operation 参数的值为良性值，程序就可以正常运行。例如，当该值为 "8 + 7 * 2" 时，calcResult 变量被赋予的值将为 22。然而，如果攻击者指定的语言操作既有可能是有效的，又有可能是恶意的，那么，只有在对主进程具有完全权限的情况下才能执行这些操作。如果底层语言提供了访问系统资源的途径或允许执行系统命令，这种攻击甚至会更加危险。对于 JavaScript，攻击者还可以利用这种漏洞进行 cross-site scripting 攻击

combining head and tail methods in R

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I use the head(d) and tail(d) methods in R package utils a lot - frequently one after the other. So i wrote a simple wrapper for the two functions: ht <- function(d, m=5, n=m){ # print the head and tail together cat(" head --> ", head(d,m), "\n", "--------", "\n", "tail --> ", tail(d,n), "\n") } And i got some unexpected results ... can someone please help me understand why? (so i can fix it ... or at least understand your solution!). Some background... Numeric is fine: x <- 1:100 ht(x) As is complex: ni <- as.complex(1:100) ht(ni) and character: ll <- letters[1:26] ht(ll) Matrix loses it's

13、linux-文件管理命令 cat、head、tail、more、less

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1.cat 文件名或者路径　　cat -n：对输出内容添加行号　　cat -b：对空白行不添加行号 2.tac：倒序查看，不能添加参数，只能单独使用 3.tail：默认显示后10行　　tail -n：显示后n行　　注：tail -f 动态显示日志文件，追踪日志动态信息 4.more：分页查看，按ctrl +f 查看全部 5.less：分页查看，按q退出查看来源： https://www.cnblogs.com/z-xiao/p/11854576.html

Why sudo cat gives a Permission denied but sudo vim works fine?

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问题 I am trying to automate the addition of a repository source in my arch's pacman.conf file but using the echo command in my shell script. However, it fails like this:- sudo echo "[archlinuxfr]" >> /etc/pacman.conf sudo echo "Server = http://repo.archlinux.fr/\$arch" >> /etc/pacman.conf sudo echo " " >> /etc/pacman.conf -bash: /etc/pacman.conf: Permission denied If I make changes to /etc/pacman.conf manually using vim, by doing sudo vim /etc/pacman.conf and quiting vim with :wq , everything

Using “cat” to write non-English characters into a .html file (in R)

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问题 Here is the code showing the problem: myPath = getwd() cat("abcd", append = T, file =paste(myPath,"temp1.html", sep = "\\")) # This is fine cat("<BR/><BR/><BR/>", append = T, file =paste(myPath,"temp1.html", sep = "\\")) # This is fine cat("שלום", append = F, file =paste(myPath,"temp1.html", sep = "\\")) # This text gets garbled when the html is opened using google chrome on windows 7. cat("שלום", append = F, file =paste(myPath,"temp1.txt", sep = "\\")) # but if I open this file in a text

find command to find files and concatenate them

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问题 I am trying to find all the files of type *.gz and cat them to total.gz and I think I am quite close on this. This is the command I am using to list all *.gz find /home/downloaded/. -maxdepth 3 -type d ( ! -name . ) -exec bash -c "ls -ltr '{}' " \ How to modify it so that it will concatenate all of them and write to ~/total.gz Update: directory structure under downloaded is as follows /downloaded/wllogs/303/07252014/SysteOut.gz /downloaded/wllogs/301/07252014/SystemOut_13.gz /downloaded

操作系统环境检查

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#一：查看cpu信息 more /proc/cpuinfo | grep "model name" grep "model name" /proc/cpuinfo grep "CPU" /proc/cpuinfo grep "model name" /proc/cpuinfo | cut -f2 -d: #二：查看内存信息 grep MemTotal /proc/meminfo grep MemTotal /proc/meminfo | cut -f2 -d: grep MemTotal /proc/meminfo | free -m grep MemTotal /proc/meminfo | grep "Mem" grep MemTotal /proc/meminfo | awk '{print $2}' #三：查看cpu是32位还是64位 getconf LONG_BIT #四：查看当前linux的版本信息 cat /etc/issue #查看具体操作系统类型 more /etc/redhat-release cat /etc/redhat-release rpm -q centos-release #五：查看内核版本 uname -r uname -a #六：查看系统当前时间 date clock #clock -w #同步系统时间 #七：查看硬盘和分区 df -h

CAT客户端如何从Apollo中读取配置？

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运行环境以下就是这个示例的运行环境，如果版本号不一样，区别也应该不会很大，可以根据实际情况做相应调整。 JDK 8 spring boot 2.0.7.RELEASE cat-client 3.0.0 apollo-client 1.3.0 欢迎关注微信公众号：万猫学社，每周一分享Java技术干货。去除Apollo对CAT的依赖众所周知，Apollo对CAT是有依赖的，但不是强依赖，而是使用了SPI技术，只有项目里引用了cat-client才会生效。目前我们想把CAT客户端配置放在Apollo里，也就是在CAT客户端初始化之前从Apollo读取相应配置，这就形成了循环依赖，所以首先要去除Apollo对CAT客户端的依赖。查看Apollo客户端的源码，我发现有一个叫做 MessageProducerManager 的接口，再看一下META-INF\services\com.ctrip.framework.apollo.tracer.spi.MessageProducerManager文件，发现这个接口的默认实现是 DefaultMessageProducerManager ，如果发现CAT客户端被引入时，这个类就会初始化CAT客户端并向CAT客户端发送消息。 MessageProducerManager 接口还有另外一个实现，就是

in R, can I stop print(cat(“”)) from returning NULL? and why does cat(“foo”) return foo>

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If I enter print(cat("")) I get NULL I want to use cat() to print out the progress of an R script, but I don't understand why it is returning NULL at the end of all of my concatenated strings, and more importantly, how to get it to stop? All your answers are in the documentation for ?cat . The portions that answer your specific question are: Arguments: fill: a logical or (positive) numeric controlling how the output is broken into successive lines. If ‘FALSE’ (default), only newlines created explicitly by ‘"\n"’ are printed. Otherwise, the output is broken into lines with print width equal to

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