RAHASH2(1)

💖 RAHASH2(1) 💖

okay bestie, gather round, because this is rahash2 — the Block-Based Hashing, Encoding, and Encryption Utility — and she is that girl. one command, so many glow-ups. ✨

---

🌈 SYNOPSIS 🌈

rahash2 [-BehjkLqRrvX] [-b S] [-a A] [-c H] [-E A] [-D A] [-s S] [-f O]
        [-t O] [-i num] [-I iv] [-S seed] [-x hexstr] [file ...]

---

🦋 DESCRIPTION 🦋

so basically? this little icon computes, verifies and shows off hash values for each block of a file, and the default block size is 32768 bytes, no cap. you can feed her from standard input using - (yes, just the dash, she gets it), and she also supports comparing against hashes you already know about, using exit status codes as the vibe check. 💅

she's commonly used for forensic analysis, for detecting file modifications, and for chewing through big files efficiently — main character energy, honestly.

she also supports entropy calculation, targeted hashing of file segments or strings, and encoding, decoding, encryption and decryption with a whole roster of cryptographic algorithms. it's giving full-stack.

✨ the flags, aka her entire personality ✨

• -a algo — comma separated list of algorithms (default is 'sha256')
• -b bsize — specify the size of the block (instead of full file)
• -B — show per-block hash
• -c hash — compare with this hash
• -e — swap endian (use little endian)
• -E algo — encrypt. use -S to set key and -I to set IV
• -D algo — decrypt. use -S to set key and -I to set IV
• -f from — start hashing at given address
• -i num — repeat hash N iterations (f.ex: 3DES)
• -I iv — use give initialization vector (IV) (hexa or s:string)
• -j — output in json
• -J — new simplified json output (same as -jj)
• -S seed — use given seed (hexa or s:string) use ^ to prefix (key for -E) (- will slurp the key from stdin, the @ prefix points to a file)
• -k — show hash using the openssh's randomkey algorithm
• -q — run in quiet mode (-qq to show only the hash)
• -L — list muta plugins (combines with -q, used by -a, -E and -D)
• -r — output radare commands (comments), for example:

$ rahash2 -a sha1 -r file | r2 -qni file

• -R — output radare2 sdb commands to store hashes under file.<algo> keys (works with any algorithm name), for example:

$ rahash2 -a sha1 -R file | r2 -qni file

🚨 heads up bestie: rahash2 -R is incompatible with -B (per-block hashing). do not try it. pick a lane.

• -s string — hash this string instead of files
• -t to — stop hashing at given address
• -x hexstr — hash this hexpair string instead of files
• -X — output in hexpairs instead of binary/plain
• -v — show version information

---

🌸 ENVIRONMENT 🌸

Rahash2 does not use any environment variables. she's low maintenance like that. 💜 zero opinions, zero drama, just vibes.

---

🎀 EXAMPLES 🎀

calculate the MD5 hash of the 'ls' binary:

$ rahash2 -qqa md5 /bin/ls

calculate the SHA256 hash of string from stdin:

$ echo -n "Hello, World" | rahash2 -a sha256 -
$ rahash2 -a sha256 -s "Hello, World"

compare CRC32 of the given file didnt changed:

$ rahash2 -qqa crc32 /bin/ls
63212007
$ rahash2 -a crc32 -c 63212007 /bin/ls
INFO: Computed hash matches the expected one
$ echo $?
0

list all muta (hash, crypto, encoder, charset) plugins:

$ rahash2 -L

encode the string "Hello World" with base64:

$ rahash2 -E base64 -s "Hello World"

calculate SHA256 hash of a specific part of a file:

$ rahash2 -qqa sha256 -f 0x1000 -t 0x2000 file_to_hash

encrypt and decrypt the "hello" string using the ror and rol plugins:

$ rahash2 -S 12333 -E ror -s hello && echo
Cell{
$ rahash2 -S 12333 -E rol -s Cell{ && echo
hello

encrypting and decrypting using AES-CBC:

$ export AES_KEY="11111111111111111111111111113211"
$ rahash2 -E aes-ecb -S "$AES_KEY" -s "hello world you bastard" > .file
$ cat .file | rahash2 -D aes-ecb -S "$AES_KEY" -s - && echo

encrypting a file using Blowfish and encode it into a json:

$ rahash2 -E blowfish -S "11111111111111111111111111113211" -j /bin/ls > ls.json

---

🫶 DIAGNOSTICS 🫶

the rahash2 utility exits 0 on success, and >0 if an error occurs. simple as.

when using the -c flag, an exit status of 0 indicates a match between the expected and computed hashes. queen of accountability. 👑

---

👀 SEE ALSO 👀

• radare2(1)

---

💜 AUTHORS 💜

pancake <pancake@nopcode.org>

---

and that's the whole page, bestie! this lil bundle of joy was written up on Jul 10, 2025, and it lives in the RAHASH2(1) section of the manual — go forth and hash responsibly. mwah. 💋✨🌈