Bitcoin Wiki - User contributions [en]

Bitcoin symbol

2013-01-14T18:51:47Z

Hulten: /* Currency code */

== Currency code ==
The [https://secure.wikimedia.org/wikipedia/en/wiki/ISO_4217 currency code] for Bitcoin is '''BTC'''. However, at the moment it is an [https://secure.wikimedia.org/wikipedia/en/wiki/ISO_4217#Without_currency_code unofficial code] according to the ISO 4217 standard but the official code according to the Bitcoin community.

A [https://bitcointalk.org/index.php?topic=7205.msg112577 request] has been made at the [http://www.six-group.com/ organization] maintaining the currency codes in the ISO 4217 standard to support BTC. This has been declined mainly on bases that organizations such as [https://secure.wikimedia.org/wikipedia/en/wiki/Reuters Reuters] and [https://secure.wikimedia.org/wikipedia/en/wiki/Bloomberg Bloomberg] are not reporting on the Bitcoin currency. When this changes, a request can be resubmitted.

== Currency sign ==

B⃦ has been the standard currency sign for BTC for a long time. Some existing Unicode symbols have been proposed but also serious work is being done on creating a custom Bitcoin sign with its own official [https://secure.wikimedia.org/wikipedia/en/wiki/Unicode Unicode] that is recognized by the [https://secure.wikimedia.org/wikipedia/en/wiki/Unicode_Consortium Unicode Consortium]. Note that a currency sign is more complex than creating a logo as will be explained below.

[[File:Example-unicode-reference-currency-signs.png|256px|thumb|right|Examples of Unicode currency sign reference glyphs]]

=== New Unicode symbol ===

In some discussions [https://bitcointalk.org/index.php?topic=41.0 41], [https://bitcointalk.org/index.php?topic=369.0 369] and [https://bitcointalk.org/index.php?topic=7215.0 7215] on the bitcoin forum several designs of an official Bitcoin sign have been proposed. This section on the Wiki is intended to streamline the process of arriving at an official Bitcoin currency sign with its own Unicode character code.

==== Goal ====
Having a unique Bitcoin currency sign will allow typographers to add their currency sign design in their fonts. This is similar as implementing support for the euro sign. Each font has its own version of the euro sign that fits with the style observed in the characters in the rest of the fonts of their typefaces. Note that the Unicode Consortium does not endorse Bitcoin in any way by assigning a Unicode character code, however, having a Unicode for the Bitcoin sign will also be good for PR and help having Bitcoin be taken more seriously.

==== Requirements and criteria ====

A reference Bitcoin sign could/should/must be:
* recognizable as a [https://secure.wikimedia.org/wikipedia/en/wiki/Currency_sign currency sign] such as $ € ¥ £ ¢ (e.g. with one or two vertical or horzontal bars)
* not confusing with existing currency sign such as Thai Baht ฿
* build from recognizable existing characters found on most [https://secure.wikimedia.org/wikipedia/en/wiki/Keyboard_layout#United_States QWERTY keyboards] such as bar |, minus -, hash # and/or capital B referring to currencies and '''B'''itcoin
* easy to use in handwriting
* easy to compose with one or more [https://help.ubuntu.com/community/GtkComposeTable#The%20Gtk%20Compose%20Table compose seuquences] that are still free and refer to the elements recognizable in the sign (For example the euro sign can be composed from = and C even though the = and C are not part of how it is pronounced.)
* ''possible'' to implement in [https://secure.wikimedia.org/wikipedia/en/wiki/Serif serif and sans-serif] (Most of the [http://www.unicode.org/charts/PDF/U20A0.pdf Unicode reference implementations] are made with serifs but sans-serif also exist in sans-serif fonts. So a reference implementation in serif to what is found in the PDF is preferred.)
* ''possible'' to implement in regular, italic, bold and bold italic (for sans-serif the italic will simply be a slanted version)
* in [https://secure.wikimedia.org/wikipedia/en/wiki/SVG SVG] and use this [http://pastebin.com/raw.php?i=FVY8W1W3 template] (save as bitcoin-sign-20110719-template.svg) with updated metadata and public domain or similar free/open/libre license

Note that a reference Bitcoin sign will only be used as a reference by the Unicode Consortium and it is up to typographers to implement their version matching the style of their typefaces and fonts.

==== Submissions====

It is possible to submit proposals for a '''reference implementation''' below until (community must determine date). They will be judged by (community must form committee for this). If you have problems submitting your design, ask a friend with knowledge on editing wikipedia for help.

{| class="wikitable sortable"
|-
! Preview !! Handwritten !! Associations !! Compose sequence(s) !! Designer !! Link to SVG file !! Notes
|-
| [[File:Bitcoin-proposal-1.png|128px]]
|| [[File:Hashbtc.jpg|128px]]
|| hash (#), numeral three (3)
|| B#, #B, 3#, #3
|| Wareen
|| [http://pastebin.com/raw.php?i=MRfcm0Cn Bitcoin-proposal-1.svg]
|| proposal based on original design idea from [https://bitcointalk.org/index.php?topic=41.msg348274#msg348274 RylandAlmanza] and [https://bitcointalk.org/index.php?topic=25102.msg325489#msg325489 netrin]
|-
| [[File:Bitcoin-sign-20110719.png|128px]]
|| [[file:Img075.jpg|128px]]
|| double barred dollar sign ($), capital b (B)
|| B|, |B, B=, =B
|| Pander
|| [http://pastebin.com/raw.php?i=XYsc9DeS bitcoin-sign-20110719.svg]
|| example submission based on [[File:F33980a445.png]]
|}

=== Existing Unicode symbol ===

There is a discussion over [https://bitcointalk.org/index.php?topic=369.0 which Unicode symbol might be the best suited] for bitcoin.

To type Unicode characters, refer to:

* [[Microsoft Windows Unicode Input]]
* [[How to easily type the circled B symbol on a Mac]]

It has led to the following options:

{| class="wikitable sortable"
|-
! Proposed character !! Description & Pros & Cons !! Unicode name !! Unicode decimal input !! Unicode hex input
|-
| ฿ ||
* Pros: Gives a currency-like look (it is the symbol for an existing currency, the Thai Baht, but other currency symbols often get reused, like the $); displayed correctly on all known OSes
* Cons: It is already used for the Thai currency, and might confuse people
|| THAI CURRENCY SYMBOL BAHT || || Alt +0E3F
|-
| Ⓑ ||
*Pros: Similar to current bitcoin.org logo
|| CIRCLED LATIN CAPITAL LETTER B || || Alt +24B7
|-
| B⃫ ||
|| LATIN CAPITAL LETTER B + COMBINING LONG DOUBLE SOLIDUS OVERLAY || U+0042 U+20EB
|-
| B⃦ ||
*Pros: Similar to current bitcoin.org logo
|| LATIN CAPITAL LETTER B + COMBINING DOUBLE VERTICAL STROKE OVERLAY || U+0042 U+20E6
|-
| ⓑ ||
*Pros: Small b represent the unit bit in computer where capital B is Byte
* Cons: Small fonts are harder to read
|| CIRCLED LATIN SMALL LETTER B || ||Alt +24D1
|-
|ᴃ|| || LATIN LETTER SMALL CAPITAL BARRED B || ||Alt +1D03
|-
|Ƀ||
*Pros: [http://www.ecogex.com/bitcoin/ See the project Ƀ Another Bitcoin identity]
|| LATIN CAPITAL LETTER B WITH STROKE || ||Alt +0243
|-
|B⃦|| || || ||
|-
|␢|| || (Unicode Block: Control Pictures) BLANK SYMBOL (graphic for space) || || Alt +2422
|-
|-
| 币 || pronounced "bi", combines "b", turned "c" and "T", many Chinese users, also 网民币 - Wangminbi, "The Netizen's Currency" (pun on Renminbi) || Chinese for "Currency" || || U+5E01
|-
| β ||
*Pros: Fluid look and easy to write; Lowercase<br/>
*Cons: Languages that use this character don't consider it a B. in Greek it's a V, and the German character it resembles is a hard S.
|| GREEK SMALL LETTER BETA || ||Alt +03B2
|-
|¤|| || CURRENCY SIGN ||Alt 0164 ||Alt +00A4
|-
|Ƅ|| || LATIN CAPITAL LETTER TONE SIX || ||Alt +0184
|-
|∄|| || (Unicode Block: Mathematical Operators) THERE DOES NOT EXIST || ||Alt +2204
|-
|ઘ|| || GUJARATI LETTER GHA (Indo-Aryan language) || ||Alt +0A98
|-
|ϭ|| || (Unicode Block: Greek and Coptic) COPTIC SMALL LETTER SHIMA || ||Alt +03ED
|-
| ɸ || contains 0 and I || Greek small Phi || || U+0278
|-
| ∆ || delta for "digital" || Greek capital Delta. (In Greek it's pronounced as the "th" in "then" and not like "d" in "digital". || || U+0394
|-
|[[Image:Bitcoin Symbol Suggestion circled struck-through B.png|20px]]||
* Cons: Does not exist in the Unicode standard
|| || ||
|-
|[[Image:Bitcoin Symbol Suggestion rotated power.png|20px]]||
* Cons: Does not exist in the Unicode standard
|| || ||
|-
|ⓢ|| Purposed as a smaller unit of bitcoin. E.g. A hundredth of a bitcoin || CIRCLED LATIN SMALL LETTER S || || Alt +24E2
|-
|≡ || three bars like three bits
cons: this resembles the letter ksi (Ξ) in Greek and it sounds like "x" in "axiom". || || || Alt + 240
|-
|[[Image:Bat.png|32x32px|alt=The b'at]]
the b'at
||
* Pros: Is round like a coin. Contains the B for Bitcoin. Borrows a style widelly associated with the internet. Not used for other meanings.
* Cons: Does not exist in the Unicode standard
* Cons: Very similar to the existing trademarked Broad logo [[http://www.broad.com/]]
|| || ||
|-
|A 'C' with '1' and '0' inside [[http://img829.imageshack.us/img829/8840/bitcoinlogodraft.png]]||
* Cons: Does not exist in the Unicode standard
|| || ||
|-
|A 'C' with a 'circle' and 'dot' inside [[http://img836.imageshack.us/img836/6006/bitcoinlogodraftii.png]]||
* Cons: Does not exist in the Unicode standard
|| || ||
|-
| ◪|| || (Unicode Block: Geometric Shapes) SQUARE WITH LOWER RIGHT DIAGONAL HALF BLACK || || Alt +25EA
|-
|[[http://hosting11.imagecross.com/image-hosting-61/2381unicode1s.png]][[http://hosting11.imagecross.com/image-hosting-61/162bitcoin_uni_s.png]]||
* Cons: Does not exist in the Unicode standard
|| || ||
|-
|☺|| ||WHITE SMILING FACE|| || Alt +263A
|-
|☻|| ||BLACK SMILING FACE|| || Alt +263B
|-
|㋡|| ||CIRCLED KATAKANA TU' (Japanese)|| || Alt +32E1
|-
|ᗸ|| Ressembles the striked B while being different from Baht symbol ||CANADIAN SYLLABICS CARRIER KHEE || || Alt +15F8
|}

==See Also==

* [[Promotional graphics]]

[[Category:Introduction]]

OpenSourceEncryptionSoftware

2013-01-13T12:06:46Z

Hulten: stub for the very obvious encryption tool gpg

==dm-crypt==
===Description===
Dm-crypt is part of the Linux Kernel. Some distributions might not include it in their kernel configurations, however. It is a lot like TrueCrypt: it allows you to mount encrypted files or partitions and decrypt/encrypt them on-the-fly.
===Manual setup===
Your distro probably comes with a tool to simplify using dm-crypt (also see Tomb below). However, here is how you would manually mount a file-hosted dm-crypt volume. The [http://www.paranoiacs.org/~sluskyb/hacks/hashalot/ hashalot] tool is used to prompt you for and process your password. This is used both to create the device and access it:
losetup /dev/loop0 ~/encrypted
HASH=`hashalot -s InsertSaltHere sha256 | hexdump -e '32/1 "%02x"'`
echo 0 `blockdev --getsize /dev/loop0` crypt aes-cbc-essiv:sha256 \
$HASH 0 /dev/loop0 0 | dmsetup create dmDevice
mount /dev/mapper/dmDevice /mnt/encrypted
* Losetup makes the container file (~/encrypted in this case) act like a device.
* The hashalot command prompts you for a password and then hashes it, adding the specified salt. The salt should be random, but it mustn't change.
* The hexdump command puts the binary hashalot output into the format required for dm-crypt
* Dm-crypt is set up on the /dev/loop0 device created by losetup. It uses the password hash created previously. The aes-cbc-essiv:sha256 encryption method is secure, though probably not as secure as Truecrypt's XTS method, which does not appear to be available in official kernel releases as far as I can tell. The dm-crypt device is created as /dev/mapper/dmDevice in this example.
* The device is mounted. Before you do this for the first time, you need to run mke2fs. If you ever enter the wrong password, the device will appear to contain random data and attempting to mount it will fail.

==eCryptfs==
===Description===
eCryptfs is a POSIX-compliant enterprise-class stacked cryptographic filesystem for Linux.
===Download===
[https://launchpad.net/ecryptfs Latest source link on right side of page.]

[https://launchpad.net/ecryptfs/+download All downloads.]
===Examples===
Examples can be found in Damien Oh's article [http://www.makeuseof.com/tag/encrypt-your-files-in-linux-with-ecryptfs/ How To Encrypt Files in Linux with eCryptfs.]
===FAQ===
[http://ecryptfs.sourceforge.net/ecryptfs-faq.html FAQ]
===HomePage===
[https://launchpad.net/ecryptfs eCryptfs - Enterprise Cryptographic Filesystem]
===License===
[https://launchpad.net/ubuntu/natty/+source/ecryptfs-utils/+copyright GPL 2+]

==OpenSSL==
===Description===
The OpenSSL Project is a collaborative effort to develop a robust, commercial-grade, full-featured, and Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as a full-strength general purpose cryptography library.
===Donation===
[http://www.openssl.org/support/donations.html Donation page.]
===Download===
[http://www.openssl.org/source/ Source]
===Examples===
Based on Grondilu's [http://www.bitcoin.org/smf/index.php?topic=2458.msg33379#msg33379 post,] to encrypt the wallet, from a terminal in the bitcoin parent directory, type:

openssl enc -aes256 -in ./.bitcoin/wallet.dat -out wallet.aes256

From [http://www.madboa.com/people/paul/ Paul Heinlein's] [http://www.madboa.com/geek/openssl/ openssl command line how to,] to decode, add the '-d' option, set the '-in' option to the output file name, to type:

openssl enc -d -aes256 -in wallet.aes256 -out wallet.dat

There is a small shell script that automates the whole process of 1) decrypting wallet 2) launching Bitcoin 3) encrypting the wallet afterwards and cleaning up the unencrypted bits. [http://lorelei.kaverit.org/bitcoin.sh bitcoin-launch-script]

==CCrypt==
===Description===
'''CCrypt''' is a linux command-line utility by Peter Selinger[http://www.mathstat.dal.ca/~selinger/] that replaces the Unix ''crypt'' command. '''CCrypt''' is much more secure than ''crypt'' because it uses the Rijndael block cipher, the same encryption algorithm as AES and SSL, the algoirthms of choice for the US government and the commercial banking industry. The command line syntax for '''ccrypt''' is a bit simpler than ''openssl'' because it doesn't require the user to select an encryption algorithm or name the output file, but merely specify the direction (encrypt or decrypt).

===Download===
Download the source code version of your choice at [http://ccrypt.sourceforge.net downloads] such as [http://ccrypt.sourceforge.net/download/ccrypt-1.9.tar.gz v1.9]

or in a Debian distribution like Ubuntu just execute

sudo apt-get install ccrypt

===Examples===
To encrypt your wallet:

ccrypt ~/.bitcoin/wallet.dat

To decrypt the file created above:

ccdecrypt ~/.bitcoin/wallet.dat.cpt

or
ccrypt -d ~/.bitcoin/wallet.dat.cpt

===FAQ===
[http://ccrypt.sourceforge.net/faq.html FAQ]

===HomePage===
[http://ccrypt.sourceforge.net/ Ccrypt Project on SourceForge]

===License===
[http://www.gnu.org/copyleft/gpl.html GNU General Public License.]

==Tomb==
===Description===
Tomb is a simple tool to manage encrypted storage on GNU/Linux.

Tomb generates encrypted storage files to be opened and closed using
their associated keyfiles, which are also protected with a password
chosen by the user.

A tomb is like a locked folder that can be safely transported and
hidden in a filesystem; its keys can be kept separate, for instance
keeping the tomb file on your computer harddisk and the key files on a
USB stick.

===HomePage===
[http://tomb.dyne.org Tomb - Crypto Undertaker]

===Donation===
[http://dyne.org/donate Donation page]

===Download===
[http://apt.dyne.org Binaries (WIP: Debian and Ubuntu)]

[http://ftp.dyne.org/tomb Source]

===License===
[http://www.truecrypt.org/legal/license True Crypt Open Source License.]

==True Crypt==
===Description===
Open-source disk encryption software for Windows 7/Vista/XP, Mac OS X, and Linux. True Crypt creates a virtual encrypted disk within a file and mounts it as a real disk.
===Documentation===
[http://www.truecrypt.org/docs/ Documentation page.]
===Donation===
[http://www.truecrypt.org/donations/?lnk=5 Donation page.]
===Download===
[http://www.truecrypt.org/downloads Binaries]

[http://www.truecrypt.org/downloads2 Source]
===FAQ===
[http://www.truecrypt.org/faq FAQ]
===HomePage===
[http://www.truecrypt.org/ TrueCrypt]
===License===
[http://www.truecrypt.org/legal/license True Crypt Open Source License.]

==xorsplit==
===Description===
Open-source software for Linux. xorsplit copies a file into 3 separate
backup files. Any two of the backup files are sufficient to reconstruct
the original -- but any one of the files will yield at most half of
the original information (the odd bytes or the even bytes).

Optionally, each of the backup files can be encrypted with a password.

===Home page, Download, Donation, and Documentation===
[http://www.xorsplit.com/ xorsplit.com]
===License===
[http://www.xorsplit.com/xorsplit.c BSD-style Open Source License requiring
that the donation address remain unchanged.]

===Usage===
xorsplit file -- splits the file into file.1, file.2, and file.3

xorsplit-p file -- same, but requesting a password (no password means no encryption)

xorsplit file.3 file.1 outfile -- combine file.1 and file.3 into outfile.

xorsplit-p file.3 file.1 outfile -- same, after using the password to decrypt

==GNU Privacy Guard==
===Description===
GnuPG allows to encrypt and sign your data.

===Homepage===
[http://www.gnupg.org/ gnupg.org]

[[Category:Technical]]
[[Category:Open Source]]