小水实验室

tcpdump usage

一、获取适配器列表
$ tcpdump -D

二、监听适配器
使用 -i 或 –interface 参数监听适配器，适配器可以用序号或名字来表示，这些内容可以通过 -D 参数获取。macOS 下监听适配器的话，必须使用 root 权限。
　如果需要详细查看报内容，可以使用 -X 参数。

$ tcpdump -i en0 -X

三、监听适配器过滤
1、过滤主机
抓取所有经过 eth1，目的或源地址是 192.168.1.1 的网络数据
$ tcpdump -i en0 host 192.168.1.1

限定源地址
$ tcpdump -i eth1 src host 192.168.1.1

限定目标地址
$ tcpdump -i eth1 dst host 192.168.1.1

2、过滤端口
抓取所有经过 eth1，目的或源端口是 25 的网络数据
$ tcpdump -i eth1 port 25

限定源端口
$ tcpdump -i eth1 src port 25

限定目标端口
$ tcpdump -i eth1 dst port 25

3、过滤网段
$ tcpdump -i eth1 net 192.168

$ tcpdump -i eth1 src net 192.168

$ tcpdump -i eth1 dst net 192.168

4、协议过滤

$ tcpdump -i eth1 arp
$ tcpdump -i eth1 ip
$ tcpdump -i eth1 tcp
$ tcpdump -i eth1 udp
$ tcpdump -i eth1 icmp

5、使用表达式
与：&& 或 and
或：|| 或 or
非：! 或 not

$ tcpdump -i eth1 ‘((tcp) and (port 80) and ((dst host 192.168.1.254) or (dst host
192.168.1.200)))’

fabric 踩坑记

安装fabric2

坑1 ：由于轻信了一开始搜索到的fabric中文文档网页，该网页已经陈旧，正确安装方式为 fabric2

pip3 install fabric2

#or

pip install fabric2

pip3 install fabric2

#or

pip install fabric2

这里直接上我写好的fabric 脚本

#!/bin/python3
#coding=utf-8
from fabric2 import Connection
from invoke import run as local

def printResult(fabricResult):
    msg = "Ran {0.command!r} on {0.connection.host}, got stdout:\n{0.stdout}----------------------------------------------"
    print(msg.format(fabricResult))

def updateNewVersion(sshConn):
    sshConn.run("sh /root/shells/update_software.sh")
    #printResult(res)


if __name__ == "__main__":
    #compile new version
    local("rm -rf ./bin/shot", pty=True )
    local("CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o ./tar/shot ./src/shot", pty=True )
    local("shasum ./bin/tar",pty=True )
    #push to dev server
    sshConn  = Connection("testserver")
    sshConn.put("./tar/shot", "/root/temp/shot_newversion")
    updateNewVersion(sshConn)

#!/bin/python3

#coding=utf-8

from fabric2 import Connection

from invoke import run as local

def printResult(fabricResult):

msg = "Ran {0.command!r} on {0.connection.host}, got stdout:\n{0.stdout}----------------------------------------------"

print(msg.format(fabricResult))

def updateNewVersion(sshConn):

sshConn.run("sh /root/shells/update_software.sh")

#printResult(res)

if __name__ == "__main__":

#compile new version

local("rm -rf ./bin/shot", pty=True )

local("CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -o ./tar/shot ./src/shot", pty=True )

local("shasum ./bin/tar",pty=True )

#push to dev server

sshConn = Connection("testserver")

sshConn.put("./tar/shot", "/root/temp/shot_newversion")

updateNewVersion(sshConn)

配置好本身ssh免密码登录

坑2：macos默认生成的id_rsa密钥格式可能不太正确，需要使用命令转换一下格式

ssh-keygen -p -m PEM -f ~/.ssh/id_rsa_testserver

1	ssh-keygen -p -m PEM -f ~/.ssh/id_rsa_testserver

#这是 ～/.ssh/config 文件中的配置
Host testserver
    HostName 192.168.1.220
    Port 10086
    User root 
    IdentityFile ~/.ssh/id_rsa_testserver

#这是～/.ssh/config 文件中的配置

Host testserver

HostName 192.168.1.220

Port 10086

User root

IdentityFile ~/.ssh/id_rsa_testserver

use jquery ajax load image and put it to image tag src in base64 way

https://stackoverflow.com/questions/19124701/get-image-using-jquery-ajax-and-decode-it-to-base64/25371174

 $.ajax({
            url: "someurltoajpeg",
            type: "GET",
            headers: {
                "Authorization" : "Basic " +  btoa("user:pw")
            },
            xhrFields: {
                withCredentials: true
            },
            mimeType: "text/plain; charset=x-user-defined"
        }).done(function( data, textStatus, jqXHR ) {
            $("#image").attr('src', 'data:image/jpeg;base64,' + base64encode(data));
        }).fail(function( jqXHR, textStatus, errorThrown ) {
            alert("fail: " + errorThrown);
        });

$.ajax({

url: "someurltoajpeg",

type: "GET",

headers: {

"Authorization" : "Basic " + btoa("user:pw")

xhrFields: {

withCredentials: true

mimeType: "text/plain; charset=x-user-defined"

}).done(function( data, textStatus, jqXHR ) {

$("#image").attr('src', 'data:image/jpeg;base64,' + base64encode(data));

}).fail(function( jqXHR, textStatus, errorThrown ) {

alert("fail: " + errorThrown);

});

function base64encode(str) {
        var CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
        var out = "", i = 0, len = str.length, c1, c2, c3;
        while (i < len) {
            c1 = str.charCodeAt(i++) & 0xff;
            if (i == len) {
                out += CHARS.charAt(c1 >> 2);
                out += CHARS.charAt((c1 & 0x3) << 4);
                out += "==";
                break;
            }
            c2 = str.charCodeAt(i++);
            if (i == len) {
                out += CHARS.charAt(c1 >> 2);
                out += CHARS.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));
                out += CHARS.charAt((c2 & 0xF) << 2);
                out += "=";
                break;
            }
            c3 = str.charCodeAt(i++);
            out += CHARS.charAt(c1 >> 2);
            out += CHARS.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4));
            out += CHARS.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >> 6));
            out += CHARS.charAt(c3 & 0x3F);
        }
        return out;
    }

function base64encode(str) {

var CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

var out = "", i = 0, len = str.length, c1, c2, c3;

while (i < len) {

c1 = str.charCodeAt(i++) & 0xff;

if (i == len) {

out += CHARS.charAt(c1 >> 2);

out += CHARS.charAt((c1 & 0x3) << 4);

out += "==";

break;

}

c2 = str.charCodeAt(i++);

if (i == len) {

out += CHARS.charAt(c1 >> 2);

out += CHARS.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4));

out += CHARS.charAt((c2 & 0xF) << 2);

out += "=";

break;

}

c3 = str.charCodeAt(i++);

out += CHARS.charAt(c1 >> 2);

out += CHARS.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4));

out += CHARS.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >> 6));

out += CHARS.charAt(c3 & 0x3F);

}

return out;

}

win10 golang sqlite3

1. 安装mingw-w64
2. 设置mingw-w64的bin目录到path，使终端可以直接找到执行gcc命令
3. 使用go env 命令检查环境变量，看有没有 CGO_ENABLED=1
4. 编译测试

附上测试代码

package main
import (
  "github.com/jinzhu/gorm"
  _ "github.com/jinzhu/gorm/dialects/sqlite"
  "fmt"
)

type User struct {
  gorm.Model
  Name         string
  Email        string  `gorm:"type:varchar(100);"`
  Role         string  `gorm:"size:255"` // set field size to 255
  Num          int     `gorm:"type:int(10)"` // set num to auto incrementable
  Address      string  `gorm:"index:addr"` // create index with name `addr` for address
}

func main() {
  db, err := gorm.Open("sqlite3", "./gormtest.db")
    if err != nil {
        fmt.Print(err)
    }
  db.AutoMigrate(&User{})
  xiaoming := User{Name:"Xiao Ming", Email:"smallming@test.com", Role:"Group manager", Num:10010, Address:"xxx road 88 no"}
  errx := db.Create(&xiaoming).Error
  if errx != nil {
      fmt.Print(errx)
  }
  defer db.Close()
}

package main

import (

"github.com/jinzhu/gorm"

_ "github.com/jinzhu/gorm/dialects/sqlite"

"fmt"

)

type User struct {

gorm.Model

Name string

Email string `gorm:"type:varchar(100);"`

Role string `gorm:"size:255"` // set field size to 255

Num int `gorm:"type:int(10)"` // set num to auto incrementable

Address string `gorm:"index:addr"` // create index with name `addr` for address

}

func main() {

db, err := gorm.Open("sqlite3", "./gormtest.db")

if err != nil {

fmt.Print(err)

}

db.AutoMigrate(&User{})

xiaoming := User{Name:"Xiao Ming", Email:"smallming@test.com", Role:"Group manager", Num:10010, Address:"xxx road 88 no"}

errx := db.Create(&xiaoming).Error

if errx != nil {

fmt.Print(errx)

}

defer db.Close()

}

监控服务是否存活脚本

HEALTHY_URL = "http://127.0.0.1:8080/alive"


RESP=curl —-connect-timeout 3 -s ${HEALTHY_URL}

if [ "$RESP" == "ok"]; then echo "Server is running." exit 1 else echo "Serve was exit." exit 0 fi

docker 查看容器详情
docker inspect 容器ID
可是使用容器的IP地址访问容器相应端口来访问到容器上的关服务

tcpdump usage

fabric 踩坑记

use jquery ajax load image and put it to image tag src in base64 way

win10 golang sqlite3

监控服务是否存活脚本

为git项目指定单独的user.name user.email

MySQL添加新用户并设置权限

php中mysql防止注入

use openssl create RSA public/private key

docker学习纪要（二）