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Goverp
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Joined: 07 Mar 2007
Posts: 2131

PostPosted: Sat Sep 07, 2024 6:45 pm    Post subject: A tiny password generator script Reply with quote

This script one-liner is a shorter version of one that appears on the Internet, using /dev/urandom:

Code:
dd if=/dev/urandom bs=12 count=1 status=none | base64


The result is a 16-byte totally unmemorable ASCII string complete (usually) with special characters, upper/lower case and numbers, so it's useful if you store the results in a password vault, but not much otherwise! Sometimes it generates unacceptable passwords - something that doesn't have special characters or numbers or perhaps special characters or whatever, so try again!

(The longer Internet version is along the lines of
Code:
dd if=/dev/urandom count=1 2> /dev/null | uuencode -m - | sed -ne 2p | cut -c-8

which takes depletes your entropy by 512 bytes before throwing most of it away, uses "uuencode", which needs an extra package, and sed and cut, and is generally nasty.)
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Zucca
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PostPosted: Sat Sep 07, 2024 7:38 pm    Post subject: Reply with quote

I've used
Code:
tr -dc '[allovedcharacters]' < /dev/random | head -c <length>

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pjp
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PostPosted: Sat Sep 07, 2024 11:22 pm    Post subject: Reply with quote

While this is a script of more than one generator, it can be reduce to one of them. I never settled on one. Also, where credit is given, mistakes should be presumed to be mine.
Code:
# passphrase
bewaitered*Aile%retrovaccinate
tycoondiceboxsuppleheptene
patientpoisedkenoticxerotic.
pyxides sail letter distad.
calaisdeadeyeinfamyamidid
Code:
#!/bin/sh

set -efu

declare -a w n
w=( $( shuf -n3 /usr/share/dict/words ) )
n=( $( shuf -n2 -e \! \" \# \$ \% \& \' \( \) \* \+ \, \- \. \/ \: \; \< \= \> \? \@ \[ \\ \] \^ \_ \` \{ \| \} \~ ) )
for i in {0..2}; do
   if [[ $(( $RANDOM % 2 )) = 0 ]]; then
      w[$i]="${w[$i]^}"
   fi
done
printf '%s%s%s%s%s\n' "${w[0]}" "${n[0]}" "${w[1]}" "${n[1]}" "${w[2]}"

###############################################################################
# Remove words with:
#   - too many or too few characters
#   - apostrophes, hyphens, or capitalization
#   - Removing spaces is optional. (eccerr0r)
echo $(egrep '^[a-z]{4,7}$' /usr/share/dict/words|shuf -n4)|tr -d ' '

###############################################################################
# - avoid use of tr with printf (Hu)
printf '%s%s%s%s\n' $(grep -E '^[a-z]{4,7}$' /usr/share/dict/words|shuf -n4).

# With spaces
printf '%s %s %s %s\n' $(grep -E '^[a-z]{4,7}$' /usr/share/dict/words|shuf -n4).

# work regardless of the shuffle count
# relies on printf to
#   - discard the whitespace (newlines)
#   - then uses a bare echo to emit a newline at the end.
{ printf '%s' $(grep -E '^[a-z]{4,7}$' /usr/share/dict/words|shuf -n4); echo; }

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sMueggli
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Joined: 03 Sep 2022
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PostPosted: Sun Sep 08, 2024 8:40 am    Post subject: Reply with quote

Code:
openssl rand -base64 12
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