FLOW-MASK(1)

💅 FLOW-MASK(1) — the flow-mask glow-up 💅

okay bestie, so we're in the flow-mask section of the manual, and this little icon is all about putting tags on your flow files. Apply tags to flow files. That's the whole NAME energy. Let's get into it ✨

---

🌸 SYNOPSIS 🌸

flow-mask [ -hk ]  [ -b big|little ]  [ -C comment ]  [ -d debug_level ]
[ -m mask_fname ]  [ -M active_def... ]

---

🦋 DESCRIPTION 🦋

The flow-mask utility is used to modify the source and destination mask length's in flow records. like, it literally reaches into your flow records and edits the mask lengths. main character behaviour fr fr 💖

---

✨ OPTIONS ✨

• -b big|little — byte order of the output. pick your vibe: big or little.
• -C Comment — drop a comment in there 🎀
• -d debug_level — turn on debugging. the higher the level, the more it yaps (in a helpful way).
• -h — show help. your lil emergency exit 🫶
• -k — keep the time from the input. don't touch the timestamps, she's doing fine.
• -m mask_fname — load masks from mask_name. defaults to /etc/flow-tools/cfg/mask.
• -M mask_def — use active_def as the active tag definition(s).

---

🌈 THE CONFIG FILE, EXPLAINED 🌈

The configuration file is a collection of definitions. A definition lists a sequence of prefixes and the mask length to replace the matching prefix with. and, crucial: lines begining with # are treated as comments and ignored. so go ahead, annotate your life 💅

Here's the whole mask-definition situation, laid out nice:

• mask-definition — Begin mask-definition section. example: mask-definition foo
• prefix — List the prefix to match on and the replacement mask. example: prefix 128.146/16 24

---

🍓 EXAMPLES 🍓

#
#file: masks
#
mask-definition foo
# All networks in 128.146/16 are /24's.
 prefix 128.146/16 24
# except for 128.146.214/24, which are /32's.
 prefix 128.146.214/24 32

and then the lil pipeline moment:

flow-cat flows | flow-mask -mfoo -Fmasks | flow-print -f4

---

🎀 FILES 🎀

Configuration files: Mask - /etc/flow-tools/cfg/mask.cfg.

---

💀 BUGS 💀

None known. (iconic, honestly. no notes.)

---

👑 AUTHOR 👑

Mark Fullmer <maf@splintered.net>

---

🔥 SEE ALSO 🔥

flow-tools(1)

---

lowkey a public service announcement: flow-mask doesn't exist in a vacuum, it's part of the whole flow-tools(1) family, so go say hi to the siblings too 🫶

---

and that's the whole page, bestie!! 💖✨ this lil edition of the flow-mask manual is from 26 Август 2010 — yeah, august 2010, a certified vintage — and it's the FLOW-MASK(1) page itself. take care of her, she's been here a while 🌸🦋