Initial commit

.editorconfig

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+# editorconfig.org
+root = true
+
+[*]
+charset = utf-8
+indent_style = tab
+trim_trailing_whitespace = true
+end_of_line = lf
+insert_final_newline = true
+
+[*.md]
+indent_style = space
+indent_size = 4

.gitignore

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+# IntelliJ
+.idea/

2fa-backup-sheet.sh

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+#!/bin/bash
+
+# Exit immediately when statements or commands (outside of tests and conditions) fail (with a non-zero exit status)
+set -e
+
+# Fail on references to unset variables or parameters
+set -u
+
+# Make pipelines fail if any command within (i.e. not just the last one) fails
+set -o pipefail
+
+# Don't return literal expressions with asterisks if a glob doesn't match but instead make the glob fail
+shopt -s failglob
+
+canvasWidth=$((210 * 300 * 393701/10000000)) # mm * dpi * inch/mm
+canvasHeight=$((297 * 300 * 393701/10000000)) # mm * dpi * inch/mm
+backgroundColor="white"
+paddingTop=$((20 * 300 * 393701/10000000)) # mm * dpi * inch/mm
+paddingBottom=$((20 * 300 * 393701/10000000)) # mm * dpi * inch/mm
+textTitle=${1:-}
+textSubtitle=${3:-}
+textDate=${4:-"$(date +'%Y-%m-%d')"}
+textRecoveryCodes=${2:-}
+pathKeyUriQrCode=${5:-}
+linesTitle=$(echo "$textTitle" | sed 's/\\n/\n/g' | wc -l)
+linesSubtitle=$(echo "$textSubtitle" | sed 's/\\n/\n/g' | wc -l)
+linesDate=$(echo "$textDate" | sed 's/\\n/\n/g' | wc -l)
+linesRecoveryCodes=$(echo "$textRecoveryCodes" | sed 's/\\n/\n/g' | wc -l)
+
+if [ -n "$textTitle" ]; then hasTitle=1; else hasTitle=0; fi
+if [ -n "$textSubtitle" ]; then hasSubtitle=1; else hasSubtitle=0; fi
+if [ -n "$textDate" ]; then hasDate=1; else hasDate=0; fi
+if [ -n "$textRecoveryCodes" ]; then hasRecoveryCodes=1; else hasRecoveryCodes=0; fi
+if [ -n "$pathKeyUriQrCode" ]; then hasKeyUriQrCode=1; else hasKeyUriQrCode=0; fi
+
+qrCodeSize=$((canvasWidth * 2/5))
+fontPathRegular=${6:-"/usr/share/fonts/truetype/ubuntu/UbuntuMono-R.ttf"}
+
+if [ -z "${6:-}" ]; then
+	fontPathBold=${7:-"/usr/share/fonts/truetype/ubuntu/UbuntuMono-B.ttf"}
+else
+	fontPathBold=${7:-${fontPathRegular}}
+fi
+
+fontScale=${8:-"100"}
+fontSizeTitle=$((160 * fontScale/100))
+fontSizeSubtitle=$((112 * fontScale/100))
+fontSizeDate=$((112 * fontScale/100))
+
+if [ "$hasKeyUriQrCode" -eq 1 ]; then
+	fontSizeRecoveryCodes=$((72 * fontScale/100))
+else
+	fontSizeRecoveryCodes=$((96 * fontScale/100))
+fi
+
+upperHeight=$((canvasHeight * 1/2 - qrCodeSize * 1/2))
+
+if [ "$hasTitle" -eq 1 ] || [ "$hasSubtitle" -eq 1 ] || [ "$hasDate" -eq 1 ]; then
+	upperSpacing=$(((upperHeight - paddingTop - fontSizeTitle - fontSizeSubtitle - fontSizeDate) / (hasTitle + hasSubtitle + hasDate)))
+else
+	upperSpacing=0
+fi
+
+lowerHeight=$((canvasHeight * 1/2 - qrCodeSize * 1/2))
+
+if [ "$hasRecoveryCodes" -eq 1 ]; then
+	lowerSpacing=$(((lowerHeight - paddingBottom - fontSizeRecoveryCodes * linesRecoveryCodes * hasRecoveryCodes) / hasRecoveryCodes))
+else
+	lowerSpacing=0
+fi
+
+positionVerticalTitle=$paddingTop
+positionVerticalSubtitle=$((paddingTop + (fontSizeTitle + upperSpacing) * hasTitle))
+positionVerticalDate=$((paddingTop + (fontSizeTitle + upperSpacing) * hasTitle + (fontSizeSubtitle + upperSpacing) * hasSubtitle))
+positionVerticalRecoveryCodes=$((upperHeight + qrCodeSize + lowerSpacing))
+outputFilename=${9:-"2fa-backup-$(date +'%Y%m%dT%H%M%S').png"}
+outputFileBasename="${outputFilename%.*}"
+outputFileExtension="${outputFilename##*.}"
+
+if [ "$#" -lt 2 ]; then
+	echo 'Usage:'
+	echo '  $ bash ./2fa-backup-sheet.sh <TITLE> <RECOVERY_CODES> [<SUBTITLE> [<DATE> [<OTP_KEY_URI_QR_PATH> [<FONT_PATH_REGULAR> [<FONT_PATH_BOLD> [<FONT_SCALE> [<OUTPUT_FILE_PATH>]]]]]]]'
+	echo ''
+	echo '  # e.g.'
+	echo ''
+	# shellcheck disable=SC2028
+	echo '  # bash ./2fa-backup-sheet.sh "Google" "2589 0449\n5908 3492\n8491 4533\n2560 0808"'
+	echo '  # or'
+	# shellcheck disable=SC2028
+	echo '  # bash ./2fa-backup-sheet.sh "Twitter" "3234 8651\n5962 8640\n2490 2239\n2873 6327\n5730 5927\n4371 8506\n9858 8718\n3884 9458\n9110 6833\n8815 4916" "[email protected]" "" "key-uri-qr-code-screenshot.png" "RobotoMono-Regular.ttf" "RobotoMono-Bold.ttf" "75" "backup-sheet-twitter.png"'
+	exit 1
+fi
+
+if [ "$linesTitle" -gt 1 ]; then
+	echo ' ! You cannot use more than 1 line of text in the title'
+	exit 2
+fi
+
+if [ "$linesSubtitle" -gt 1 ]; then
+	echo ' ! You cannot use more than 1 line of text in the subtitle'
+	exit 3
+fi
+
+if [ "$linesDate" -gt 1 ]; then
+	echo ' ! You cannot use more than 1 line of text for the date'
+	exit 4
+fi
+
+if [ "$linesRecoveryCodes" -gt 10 ]; then
+	echo ' ! You cannot use more than 10 lines of text for the recovery codes'
+	exit 5
+fi
+
+if [ ! -r "$fontPathRegular" ]; then
+	echo ' ! Could not read path for regular font'
+	exit 6
+fi
+
+if [ ! -r "$fontPathBold" ]; then
+	echo ' ! Could not read path for bold font'
+	exit 7
+fi
+
+if [ "$hasKeyUriQrCode" -eq 1 ]; then
+	# Remove areas surrounding QR code itself
+	convert "$pathKeyUriQrCode" -bordercolor white -border 1x1 -white-threshold 50% -transparent white -trim +repage "${outputFileBasename}.2cdcd308.${outputFileExtension}"
+	# Resize the QR code to the desired size
+	convert "${outputFileBasename}.2cdcd308.${outputFileExtension}" -resize "${qrCodeSize}x${qrCodeSize}" "${outputFileBasename}.3f9de271.${outputFileExtension}"
+	# Remove temporary file
+	rm "${outputFileBasename}.2cdcd308.${outputFileExtension}"
+	# Place the QR code at the center of the overall canvas
+	convert "${outputFileBasename}.3f9de271.${outputFileExtension}" -gravity center -background "$backgroundColor" -extent "${canvasWidth}x${canvasHeight}" "${outputFileBasename}.f576a167.${outputFileExtension}"
+	# Remove temporary file
+	rm "${outputFileBasename}.3f9de271.${outputFileExtension}"
+else
+	convert -size "${canvasWidth}x${canvasHeight}" canvas:"$backgroundColor" "${outputFileBasename}.f576a167.${outputFileExtension}"
+fi
+
+# Write the title to the canvas
+convert "${outputFileBasename}.f576a167.${outputFileExtension}" -gravity north -font "$fontPathBold" -pointsize "$fontSizeTitle" -annotate "+0+${positionVerticalTitle}" "$textTitle" "${outputFileBasename}.8822c7ef.${outputFileExtension}"
+# Remove temporary file
+rm "${outputFileBasename}.f576a167.${outputFileExtension}"
+# Write the subtitle to the canvas
+convert "${outputFileBasename}.8822c7ef.${outputFileExtension}" -gravity north -font "$fontPathRegular" -pointsize "$fontSizeSubtitle" -annotate "+0+${positionVerticalSubtitle}" "$textSubtitle" "${outputFileBasename}.25a0da4b.${outputFileExtension}"
+# Remove temporary file
+rm "${outputFileBasename}.8822c7ef.${outputFileExtension}"
+# Write the date to the canvas
+convert "${outputFileBasename}.25a0da4b.${outputFileExtension}" -gravity north -font "$fontPathRegular" -pointsize "$fontSizeDate" -annotate "+0+${positionVerticalDate}" "$textDate" "${outputFileBasename}.6a23dc41.${outputFileExtension}"
+# Remove temporary file
+rm "${outputFileBasename}.25a0da4b.${outputFileExtension}"
+# Write the recovery codes to the canvas
+convert "${outputFileBasename}.6a23dc41.${outputFileExtension}" -gravity north -font "$fontPathRegular" -pointsize "$fontSizeRecoveryCodes" -annotate "+0+${positionVerticalRecoveryCodes}" "$textRecoveryCodes" "${outputFileBasename}.345599c2.${outputFileExtension}"
+# Remove temporary file
+rm "${outputFileBasename}.6a23dc41.${outputFileExtension}"
+# Move the result so that the output file has the desired filename
+mv "${outputFileBasename}.345599c2.${outputFileExtension}" "$outputFilename"
+
+echo 'Written to:'
+echo "  $outputFilename"
+
+exit 0

LICENSE

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+The MIT License (MIT)
+
+Copyright (c) delight.im (https://www.delight.im/)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# 2FA-Backup-Sheet
+
+Create backup sheets for any service where you use two-factor authentication (2FA)
+
+Full | Minimal
+:-------------------------:|:-------------------------:
+<img src="sample-sheet-full.png?raw=true" alt="Full" width="300" /> | <img src="sample-sheet-minimal.png?raw=true" alt="Minimal" width="300" />
+
+## Requirements
+
+ * Unix
+   * Bash
+   * ImageMagick
+
+## Usage
+
+```bash
+$ bash ./2fa-backup-sheet.sh \
+    <TITLE> \
+    <RECOVERY_CODES> \
+    [<SUBTITLE> \
+    [<DATE> \
+    [<OTP_KEY_URI_QR_PATH> \
+    [<FONT_PATH_REGULAR> \
+    [<FONT_PATH_BOLD> \
+    [<FONT_SCALE> \
+    [<OUTPUT_FILE_PATH>]]]]]]]
+```
+
+### Examples
+
+```bash
+$ bash ./2fa-backup-sheet.sh \
+    "Google" \
+    "2589 0449\n5908 3492\n8491 4533\n2560 0808"
+
+# or
+
+$ bash ./2fa-backup-sheet.sh \
+    "Twitter" \
+    "3234 8651\n5962 8640\n2490 2239\n2873 6327\n5730 5927\n4371 8506\n9858 8718\n3884 9458\n9110 6833\n8815 4916" \
+    "[email protected]" \
+    "" \
+    "key-uri-qr-code-screenshot.png" \
+    "RobotoMono-Regular.ttf" \
+    "RobotoMono-Bold.ttf" \
+    "75" \
+    "backup-sheet-twitter.png"
+```
+
+### Security
+
+Do *not* store the resulting backup sheets in the same place as your passwords, if such a place exists. For example, if you use a password manager to store your passwords, do *not* save your recovery codes or backup sheets there. Consider storing the backup sheets only in *printed form*, and put them in a safe place – perhaps even at two separate physical locations.
+
+If you want to include a QR code representing the key URI, which includes the shared secret or seed, you may want to take a screenshot of the QR code shown to you by the service in question. If you save the QR code directly, e.g. in your web browser, a new code (and thus secret) *may* be generated, depending on the service and the software you use. After generating the backup sheet, delete the screenshot that you took.
+
+## Contributing
+
+All contributions are welcome! If you wish to contribute, please create an issue first so that your feature, problem or question can be discussed.
+
+## License
+
+This project is licensed under the terms of the [MIT License](https://opensource.org/licenses/MIT).