net/ddns-scripts/files/usr/lib/ddns/shell_get.sh

   1 #######################################################################
   2 #/usr/lib/ddns/shell_get.sh
   3 #
   4 # Written by Eric Bishop, January 2008
   5 # Distributed under the terms of the GNU General Public License (GPL) version 2.0
   6 #
   7 # This implements a wget-like program ("shell_get 1.0") that can handle
   8 # basic http username/password authentication.
   9 # It is implemented using the netcat (nc) utility.
  10 # This is necessary because the default busybox wget
  11 # does not include username/password functionality (it really sucks)
  12 ##########################################################################
  13
  14 to_ascii()
  15 {
  16         dec=$1
  17         hex=""
  18         if [ $dec -lt 26 ]; then
  19                 hex=$(($dec + 0x41))
  20         elif [ $dec -ge 26 ] && [ $dec -lt 52 ]; then
  21                 hex=$(( ($dec-26) + 0x61))
  22         elif [ $dec -ge 52 ] && [ $dec -lt 62 ]; then
  23                 hex=$(( ($dec-52) + 0x30))
  24         elif [ $dec -eq 62 ]; then
  25                 hex=43
  26         else
  27                 hex=47
  28         fi
  29         printf "%x" $hex
  30 }
  31
  32 encode_base64()
  33 {
  34         original_str=$1
  35
  36         hex_str=$( echo -n "$original_str" | hexdump -v | awk '{ for ( i = 2; i <= NF; i++ ) {  h1=substr($i, 3, 2); h2=substr($i,0,2); printf("%s%s", h1, h2); }}' | awk ' { $0~gsub(/00$/, "") };{ i=1; while(i <= length($0) ){ block= substr($0, i, 3); printf("%s ", block); i=i+3;  }}' | awk ' {$0~gsub(/ $/, "")}; { print $0 }' )
  37
  38         length=$(echo $hex_str | awk  '{$0~gsub(/ /, "")}; { print length($0) }')
  39         remainder=$(($length % 3 ))
  40         if [ $remainder -eq 1 ]; then
  41                 hex_str=$hex_str'00'
  42         elif [ $remainder -eq 2 ]; then
  43                 hex_str=$hex_str'0'
  44         fi
  45
  46
  47
  48
  49         base_64_str=""
  50         for hex_block in $hex_str
  51         do
  52                 char1=$(to_ascii $((0x$hex_block / 64)))
  53                 char2=$(to_ascii $((0x$hex_block % 64)))
  54                 base_64_str=$(printf "$base_64_str\x$char1\x$char2")
  55         done
  56
  57
  58         if [ $remainder -eq 1 ]; then
  59                 base_64_str=$(echo "$base_64_str" | awk '{ $0~gsub(/A$/, "=");} { print $0 }' )
  60         elif [ $remainder -eq 2 ]; then
  61                 base_64_str=$(echo "$base_64_str==")
  62         fi
  63
  64
  65         echo $base_64_str
  66 }
  67
  68 shell_get()
  69 {
  70         full_url=$1
  71
  72         protocol_str=$(echo $full_url | awk ' BEGIN {FS="://"} { if($0~/:\/\//)print $1 }')
  73         if [ "$protocol_str" != "http" ] && [ -n "$protocol_str" ] ; then
  74                 echo "protocol = $protocol_str"
  75                 echo "Error, unsupported Protocol"
  76                 echo "Only http connections are supported at this time"
  77                 return 1;
  78         fi
  79
  80
  81         if [ -n "$protocol_str" ] ; then
  82                 full_url=$(echo $full_url | awk ' {$0~gsub(/http:\/\//, "")}; {print $0}')
  83         fi
  84
  85
  86
  87         user_pass=$(echo $full_url | awk ' BEGIN {FS="@"}; { if( $0~/@/ && $1~/^[^\?\/]+:[^\?\/]+$/ ) print $1 }')
  88         host_and_args=""
  89         if [ -n "$user_pass" ]; then
  90                 host_and_args=$(echo $full_url | awk ' $0~gsub(/^[^@]+@/, "") {print $0}')
  91         else
  92                 host_and_args="$full_url"
  93         fi
  94
  95         host_name=$(echo $host_and_args | awk ' BEGIN {FS="[:?/]"}; {print $1};')
  96         port_num=$(echo $host_and_args | awk ' BEGIN {FS="[?/]"}; { if($1~/:/){$1~gsub(/.*:/, ""); print $1;}else {print "80"}};')
  97
  98         path=$(echo $host_and_args | awk ' { $0~gsub(/^[^\?\/]+/, "")}; {print $0};')
  99         path_start_test=$(echo "$path" | grep "^/")
 100         if [ -z "$path_start_test" ]; then
 101                 path="/$path"
 102         fi
 103
 104
 105         #echo "full_url=\"$full_url\""
 106         #echo "user_pass=\"$user_pass\""
 107         #echo "host_name=\"$host_name\""
 108         #echo "port_num=\"$port_num\""
 109         #echo "path=\"$path\""
 110
 111
 112         retrieved_data=""
 113         if [ -n "$user_pass" ]; then
 114                 auth_str=$(encode_base64 "$user_pass" )
 115                 #echo -e "GET $path HTTP/1.0\nHost: $host_name\nAuthorization: Basic $auth_str\nUser-Agent: shell_get 1.0\n\n"
 116                 retrieved_data=$(echo -e "GET $path HTTP/1.0\nHost: $host_name\nAuthorization: Basic $auth_str\nUser-Agent: shell_get 1.0\n\n" | nc "$host_name" $port_num | cat)
 117
 118         else
 119                 #echo -e "GET $path HTTP/1.0\nHost: $host_name\nUser-Agent: shell_get 1.0\n\n"
 120                 retrieved_data=$(echo -e "GET $path HTTP/1.0\nHost: $host_name\nUser-Agent: shell_get 1.0\n\n" | nc "$host_name" $port_num | cat)
 121         fi
 122
 123         echo -e "$retrieved_data"
 124
 125 }
 126