Commands by RAKK (5)

  • Lists directory size up to a maximum traversal depth on systems like IBM AIX, where the du command doesn't have Linux's --max-depth option. AIX's du uses -g to display directory size on gigabytes, -m to use megabytes, and -k to use kilobytes. tr### is a Perl function that replaces characters and returns the amount of changed characters, so in this case it will return how many slashes there were in the full path name. Show Sample Output


    0
    du -g | perl -ne 'print if (tr#/#/# == <maximum depth>)'
    RAKK · 2014-02-15 07:33:36 5
  • This command allows you to mirror folders or files with rsync using a secure SSH channel with a forced HMAC integrity algorithm. Use this if you are absolutely adamant about preserving data integrity while mirroring a set of files. --partial is for resumability.


    0
    rsync -av -e "ssh -o MACs=hmac-ripemd160" --progress --partial user@remotehost://path/to/remote/stuff .
    RAKK · 2014-02-01 00:46:38 3
  • This command is used to verify a sha256sum-formatted file hash list on IBM AIX or any other UNIX-like OS that has openssl but doesn't have sha256sum by default. Steps: 1: Save to the filesystem a script that: A: Receives as arguments the two parts of one line of a sha256sum listing B: Feeds a file into openssl on SHA256 standard input hash calculation mode, and saves the result C: Compares the calculated hash against the one received as argument D: Outputs the result in a sha256sum-like format 2: Make the script runnable 3: Feed the sha256sum listing to xargs, running the aforementioned script and passing 2 arguments at a time Show Sample Output


    0
    echo '#! /usr/bin/ksh\ncat $2 | openssl dgst -sha256 | read hashish; if [[ $hashish = $1 ]]; then echo $2: OK; else echo $2: FAILED; fi;' > shacheck; chmod +x shacheck; cat hashishes.sha256 | xargs -n 2 ./shacheck;
    RAKK · 2013-09-18 21:51:20 5
  • This command is for UNIX OSes that have plain vanilla System V UNIX commands instead of their more functional GNU counterparts, such as IBM AIX.


    1
    gzip -cd gzippedarchive.tar.gz | tar -xf -
    RAKK · 2013-09-18 17:41:25 6
  • This command is for producing GNU sha256sum-compatible hashes on UNIX systems that don't have sha256sum but do have OpenSSL, such as stock IBM AIX. 1.- Saves a wrapper script for UNIX find that does the following: A.- Feeds a file to openssl on SHA256 hash calculation mode B.- Echoes the output followed by the filename 2.- Makes the file executable 3.- Runs find on a directory, only processing files, and running on each one the wrapper script that calculates SHA256 hashes Pending is figuring out how to verify a sha256sum file on a similar environment. Show Sample Output


    0
    echo '#! /usr/bin/ksh\necho `cat $1 | openssl dgst -sha256` $1' > sslsha256; chmod +x sslsha256; find directory -type f -exec ./sslsha256 \{\} \;
    RAKK · 2013-09-18 17:37:50 4

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find directory with most inodes/files
Find which directory in one filesystem that contains most inodes or files.

Find the package that installed a command

List only directory names
This command would be useful when it is desirable to list only the directories. Other options Hidden directory $ ls -d .*/ Other path $ ls -d /path/to/top/directory/.*/ Long format: $ ls -ld */

Monitor logs in Linux using Tail
Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option. This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files. Putting one alias in .profile will be more useful.

show all established tcp connections on os x

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Merge bash terminal histories

Sniff ONLY POP3 authentication by intercepting the USER command
dsniff is general purpose password sniffer, it handles *lots* of different protocols, but it also handles tcp-style expressions for limiting analyzed traffic - so I can limit it to work on pop3 only.

List detailed information about a ZIP archive
list zipfile info in long Unix ``ls -l'' format.

Compute the numeric sum of a file
In the file data.txt there is a single column of numbers. Sed adds a "+" between lines and xargs prepares the output for bc. The "echo 0" is to avoid to have a "+" at the beginning of the line.


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