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Last active September 28, 2021 14:55
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Store a binary blob file in a SQLite database to get around email filters
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blob2sqlite.md

Sometimes the email filter at work tries to prevent you from sending certain files so you can use this method to get around it. For example, .app files, or executables, or installers.

tested with OS X and macOS, should work with any system with SQLite and bash installed

store the binary file as a blob in a SQLite database and then the reciepient can extract it.

Sender: add the file to db

my_file="iStat.app"
echo "create table somefiles (thefile blob);" | sqlite3 files.db
echo "insert into somefiles (thefile) values(x'$(hexdump -ve '1/1 "%0.2X"' $my_file)');" | sqlite3 files.db 2>&1


# also send the the md5 in the email

md5 "$my_file"
# md5sum on some systems

Recipient: extract the file from db

echo "select quote(thefile) from somefiles limit 1 offset 0;" | sqlite3 files.db | tr -d "X'" | xxd -r -p > iStat.zip

md5 iStat.zip
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