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bad attempt to read a stream using bash read byte by byte

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Andy 2015-09-22 17:47:37 +02:00
parent 2be33e7453
commit 250d59495b
1 changed files with 19 additions and 11 deletions
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30
ocdec.sh
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@ -127,19 +127,27 @@ function decryptFile() {
# --- Get the FileKey --- # --- Get the FileKey ---
# --- Decrypt the file --- # --- Decrypt the file ---
# TODO: to figure out how to speed-up the decryption process.
# bottlenecks:
# - awk is running really slow, consuming lot of CPU
encFileContentsALL="$(cat "${USER}/$encFilePath")" encFileContentsALL="$(cat "${USER}/$encFilePath")"
encFileContentsNOHEAD=$(echo -n "$encFileContentsALL" | sed -r 's/^HBEGIN:.+:HEND-*//') encFileContentsNOHEAD=$(echo -n "$encFileContentsALL" | sed -r 's/^HBEGIN:.+:HEND-*//')
N=0
for IV in $(echo -n "$encFileContentsNOHEAD" |grep -E -o '00iv00.{16}xx' |sed -r 's/^00iv00//;s/xx$//'); do pos=0; posc=0; encStream="";
N=$[N+1] # bottleneck: bash read by character is super slow
encFileContentsBASE64=$(echo -n "$encFileContentsNOHEAD" |awk -F '00iv00................xx' -v N=$N '{print $N}') while IFS= read -r -n1 char; do
plainFileIVHEX=$(echo -n "$IV" |od -An -tx1 |tr -dc '[:xdigit:]') (( posc++ ))
openssl enc -AES-256-CFB -d -nosalt -base64 -A -K $decFileKeyContentHEX -iv $plainFileIVHEX -in <(echo "$encFileContentsBASE64") if $(echo ${encStream: -24} |grep -Eq "^00iv00.{16}xx$"); then
#php -r "echo openssl_decrypt('$encFileContentsBASE64', 'AES-256-CFB', '$decFileKeyContent', false, '$IV');" plainIV=$(echo ${encStream: -24} |sed -r 's/^00iv00//;s/xx$//')
done encStreamReady=${encStream:((posc - pos - 1)):((pos - 24))}
(( pos=0 ))
#echo "[::] DEBUG: " $encStreamReady with $plainIV
# can decrypt now
plainFileIVHEX=$(echo -n "$plainIV" |od -An -tx1 |tr -dc '[:xdigit:]')
openssl enc -AES-256-CFB -d -nosalt -base64 -A -K $decFileKeyContentHEX -iv $plainFileIVHEX -in <(echo "$encStreamReady")
#php -r "echo openssl_decrypt('$encStreamReady', 'AES-256-CFB', '$decFileKeyContent', false, '$plainIV');"
fi
(( pos++ ))
encStream="$encStream$char"
done <<< $encFileContentsNOHEAD
# --- Decrypt the file --- # --- Decrypt the file ---
} }