检查网口流量与前10名流量大IP

此脚本包含的功能有：

1、实时监控任意网卡的流量
2、统计10秒内平均流量
3、统计每个端口在10秒内的平均流量，基于客户端和服务端端口统计。可以看出哪些端口占流量比较大，对于web服务器，一般是80端口。其它端口受到攻击时，也有可能其它端口流量比较大。所以此功能可以帮助我们端口流量是否正常。
4、统计在10s内占用带宽最大的前10个ip。此项功能可以帮助我们来查出是否有恶意占用带宽的ip。
5、统计连接状态。此项功能可以让我们看出哪些连接状态比较大。如果SYN-RECV状态比较多的话，有可以受到半连接攻击。如果ESTABLISED非常大，但通过日志发现没有那么多请求，或者通过tcpdump发现大量ip只建立连接不请求数据的话，可能是受到了全连接攻击，这时候如果你使用的是nginx服务器，可以在配置文件增加listen 80 deferred来防止。
6、统计各端口连接状态。当可能受到攻击时，此项功能可以帮助我们发现是哪个端口受到攻击。
7、统计端口为80且状态为ESTAB连接数最多的前10个IP。此项功能可以帮助我们来找出创建连接过多的Ip，进而屏蔽。
8、统计端口为80且状态为SYN-RECV连接数最多的前10个IP。当受到半连接攻击时，此项功能可以帮助我们找到恶意ip

用到的网络分析工具：

1、tcpdump:此脚本用tcpdump来统计基于ip或基于端口的流量。
2、ss：此脚本用ss命令来统计连接状态，实际使用发现ss比netstat高效得多。
3、/proc/net/dev，用来统计指定网卡的流量。

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

#!/bin/bash

#显示菜单(单选)

display_menu(){

local soft=$1

local prompt="which ${soft} you'd select: "

eval local arr=(\${${soft}_arr[@]})

while true

do

echo -e "#################### ${soft} setting ####################\n\n"

for ((i=1;i<=${#arr[@]};i++ )); do echo -e "$i) ${arr[$i-1]}"; done

echo

read -p "${prompt}" $soft

eval local select=\$$soft

if [ "$select" == "" ] || [ "${arr[$soft-1]}" == "" ];then

prompt="input errors,please input a number: "

else

eval $soft=${arr[$soft-1]}

eval echo "your selection: \$$soft"

break

fi

done

}

#把带宽bit单位转换为人类可读单位

bit_to_human_readable(){

#input bit value

local trafficValue=$1

if [[ ${trafficValue%.*} -gt 922 ]];then

#conv to Kb

trafficValue=`awk -v value=$trafficValue 'BEGIN{printf "%0.1f",value/1024}'`

if [[ ${trafficValue%.*} -gt 922 ]];then

#conv to Mb

trafficValue=`awk -v value=$trafficValue 'BEGIN{printf "%0.1f",value/1024}'`

echo "${trafficValue}Mb"

else

echo "${trafficValue}Kb"

fi

else

echo "${trafficValue}b"

fi

}

#判断包管理工具

check_package_manager(){

local manager=$1

local systemPackage=''

if cat /etc/issue | grep -q -E -i "ubuntu|debian";then

systemPackage='apt'

elif cat /etc/issue | grep -q -E -i "centos|red hat|redhat";then

systemPackage='yum'

elif cat /proc/version | grep -q -E -i "ubuntu|debian";then

systemPackage='apt'

elif cat /proc/version | grep -q -E -i "centos|red hat|redhat";then

systemPackage='yum'

else

echo "unkonw"

fi

if [ "$manager" == "$systemPackage" ];then

return 0

else

return 1

fi

}

#实时流量

realTimeTraffic(){

local eth=""

local nic_arr=(`ifconfig | grep -E -o "^[a-z0-9]+" | grep -v "lo" | uniq`)

local nicLen=${#nic_arr[@]}

if [[ $nicLen -eq 0 ]]; then

echo "sorry,I can not detect any network device,please report this issue to author."

exit 1

elif [[ $nicLen -eq 1 ]]; then

eth=$nic_arr

else

display_menu nic

eth=$nic

fi

local clear=true

local eth_in_peak=0

local eth_out_peak=0

local eth_in=0

local eth_out=0

while true;do

#移动光标到0:0位置

printf "\033[0;0H"

#清屏并打印Now Peak

[[ $clear == true ]] && printf "\033[2J" && echo "$eth--------Now--------Peak-----------"

traffic_be=(`awk -v eth=$eth -F'[: ]+' '{if ($0 ~eth){print $3,$11}}' /proc/net/dev`)

sleep 2

traffic_af=(`awk -v eth=$eth -F'[: ]+' '{if ($0 ~eth){print $3,$11}}' /proc/net/dev`)

#计算速率

eth_in=$(( (${traffic_af[0]}-${traffic_be[0]})*8/2 ))

eth_out=$(( (${traffic_af[1]}-${traffic_be[1]})*8/2 ))

#计算流量峰值

[[ $eth_in -gt $eth_in_peak ]] && eth_in_peak=$eth_in

[[ $eth_out -gt $eth_out_peak ]] && eth_out_peak=$eth_out

#移动光标到2:1

printf "\033[2;1H"

#清除当前行

printf "\033[K"

printf "%-20s %-20s\n" "Receive: $(bit_to_human_readable $eth_in)" "$(bit_to_human_readable $eth_in_peak)"

#清除当前行

printf "\033[K"

printf "%-20s %-20s\n" "Transmit: $(bit_to_human_readable $eth_out)" "$(bit_to_human_readable $eth_out_peak)"

[[ $clear == true ]] && clear=false

done

}

#流量和连接概览

trafficAndConnectionOverview(){

if ! which tcpdump > /dev/null;then

echo "tcpdump not found,going to install it."

if check_package_manager apt;then

apt-get -y install tcpdump

elif check_package_manager yum;then

yum -y install tcpdump

fi

local reg=""

local eth=""

local nic_arr=(`ifconfig | grep -E -o "^[a-z0-9]+" | grep -v "lo" | uniq`)

local nicLen=${#nic_arr[@]}

if [[ $nicLen -eq 0 ]]; then

echo "sorry,I can not detect any network device,please report this issue to author."

exit 1

elif [[ $nicLen -eq 1 ]]; then

eth=$nic_arr

else

display_menu nic

eth=$nic

fi

echo "please wait for 10s to generate network data..."

echo

#当前流量值

local traffic_be=(`awk -v eth=$eth -F'[: ]+' '{if ($0 ~eth){print $3,$11}}' /proc/net/dev`)

#tcpdump监听网络

tcpdump -v -i $eth -tnn > /tmp/tcpdump_temp 2>&1 &

sleep 10

clear

kill `ps aux | grep tcpdump | grep -v grep | awk '{print $2}'`

#处理tcpdump文件

awk '/^IP/{print;getline;print}' /tmp/tcpdump_temp > /tmp/tcpdump_temp2

awk '{len=$NF;sub(/\)/,"",len);getline;print $0,len}' /tmp/tcpdump_temp2 > /tmp/tcpdump

#10s后流量值

local traffic_af=(`awk -v eth=$eth -F'[: ]+' '{if ($0 ~eth){print $3,$11}}' /proc/net/dev`)

#打印10s平均速率

local eth_in=$(( (${traffic_af[0]}-${traffic_be[0]})*8/10 ))

local eth_out=$(( (${traffic_af[1]}-${traffic_be[1]})*8/10 ))

echo -e "\033[32mnetwork device $eth average traffic in 10s: \033[0m"

echo "$eth Receive: $(bit_to_human_readable $eth_in)/s"

echo "$eth Transmit: $(bit_to_human_readable $eth_out)/s"

echo

#统计每个端口在10s内的平均流量

regTcpdump=$(ifconfig | grep -A 1 $eth | awk -F'[: ]+' '$0~/inet addr:/{printf $4"|"}' | sed -e 's/|$//' -e 's/^/(/' -e 's/$/)\\\\\.[0-9]+:/')

echo -e "\033[32maverage traffic in 10s base on server port: \033[0m"

awk -F'[ .:]+' -v regTcpdump=$regTcpdump

'{if ($0 ~ regTcpdump){line="clients > "$8"."$9"."$10"."$11":"$12}else{line=$2"."$3"."$4"."$5":"$6" > clients"};sum[line]+=$NF*8/10}END{for (line in sum){printf "%s %d\n",line,sum[line]}}'

/tmp/tcpdump | \

sort -k 4 -nr | head -n 10 | while read a b c d;do

echo "$a $b $c $(bit_to_human_readable $d)/s"

done

echo

echo -e "\033[32maverage traffic in 10s base on client port: \033[0m"

awk -F'[ .:]+' -v regTcpdump=$regTcpdump

'{if ($0 ~ regTcpdump){line=$2"."$3"."$4"."$5":"$6" > server"}else{line="server > "$8"."$9"."$10"."$11":"$12};sum[line]+=$NF*8/10}END{for (line in sum){printf "%s %d\n",line,sum[line]}}'

/tmp/tcpdump | \

sort -k 4 -nr | head -n 10 | while read a b c d;do

echo "$a $b $c $(bit_to_human_readable $d)/s"

done

echo

#统计在10s内占用带宽最大的前10个ip

echo -e "\033[32mtop 10 ip average traffic in 10s : \033[0m"

awk -F'[ .:]+' -v regTcpdump=$regTcpdump

'{if ($0 ~ regTcpdump){line=$2"."$3"."$4"."$5" > "$8"."$9"."$10"."$11":"$12}else{line=$2"."$3"."$4"."$5":"$6" > "$8"."$9"."$10"."$11};sum[line]+=$NF*8/10}END{for (line in sum){printf "%s %d\n",line,sum[line]}}'

/tmp/tcpdump | \

sort -k 4 -nr | head -n 10 | while read a b c d;do

echo "$a $b $c $(bit_to_human_readable $d)/s"

done

echo

#统计连接状态

regSS=$(ifconfig | grep -A 1 $eth | awk -F'[: ]+' '$0~/inet addr:/{printf $4"|"}' | sed -e 's/|$//')

ss -an | grep -v -E "LISTEN|UNCONN" | grep -E "$regSS" > /tmp/ss

echo -e "\033[32mconnection state count: \033[0m"

awk 'NR>1{sum[$(NF-4)]+=1}END{for (state in sum){print state,sum[state]}}' /tmp/ss | sort -k 2 -nr

echo

#统计各端口连接状态

echo -e "\033[32mconnection state count by port: \033[0m"

awk

'NR>1{sum[$(NF-4),$(NF-1)]+=1}END{for (key in sum){split(key,subkey,SUBSEP);print subkey[1],subkey[2],sum[subkey[1],subkey[2]]}}'

/tmp/ss | sort -k 3 -nr | head -n 10

echo

#统计端口为80且状态为ESTAB连接数最多的前10个IP

echo -e "\033[32mtop 10 ip ESTAB state count at port 80: \033[0m"

cat /tmp/ss | grep ESTAB | awk -F'[: ]+' '{sum[$(NF-2)]+=1}END{for (ip in sum){print ip,sum[ip]}}' | sort -k 2 -nr | head -n 10

echo

#统计端口为80且状态为SYN-RECV连接数最多的前10个IP

echo -e "\033[32mtop 10 ip SYN-RECV state count at port 80: \033[0m"

cat /tmp/ss | grep -E "$regSS" | grep SYN-RECV | awk -F'[: ]+' '{sum[$(NF-2)]+=1}END{for (ip in sum){print ip,sum[ip]}}' | sort -k 2 -nr | head -n 10

}

main(){

while true; do

echo -e "1) real time traffic.\n2) traffic and connection overview.\n"

read -p "please input your select(ie 1): " select

case $select in

1) realTimeTraffic;break;;

2) trafficAndConnectionOverview;break;;

*) echo "input error,please input a number.";;

esac

done

}

main

转载：http://jin771998569.blog.51cto.com/2147853/1587726

秒客网

检查网口流量与前10名流量大IP

相关文章