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Javascript SHA-1：Secure Hash Algorithm_基础知识

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发布： 2016-05-16 19:23:10
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From:http://pajhome.org.uk/crypt/md5/sha1src.html
<SPAN class=comment>/*
 * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
 * in FIPS PUB 180-1
 * Version 2.1a Copyright Paul Johnston 2000 - 2002.
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for details.
 */</SPAN>

<SPAN class=comment>/*
 * Configurable variables. You may need to tweak these to be compatible with
 * the server-side, but the defaults work in most cases.
 */</SPAN>
<SPAN class=reserved_word>var</SPAN> hexcase <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> <SPAN class=comment>/* hex output format. 0 - lowercase; 1 - uppercase    */</SPAN>
<SPAN class=reserved_word>var</SPAN> b64pad <SPAN class=symbol>=</SPAN> <SPAN class=string>""</SPAN><SPAN class=symbol>;</SPAN> <SPAN class=comment>/* base-64 pad character. "=" for strict RFC compliance  */</SPAN>
<SPAN class=reserved_word>var</SPAN> chrsz  <SPAN class=symbol>=</SPAN> <SPAN class=numeric>8</SPAN><SPAN class=symbol>;</SPAN> <SPAN class=comment>/* bits per input character. 8 - ASCII; 16 - Unicode   */</SPAN>

<SPAN class=comment>/*
 * These are the functions you'll usually want to call
 * They take string arguments and return either hex or base-64 encoded strings
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> hex_sha1<SPAN class=braces>(</SPAN>s<SPAN class=braces>)</SPAN><SPAN class=braces>{</SPAN><SPAN class=reserved_word>return</SPAN> binb2hex<SPAN class=braces>(</SPAN>core_sha1<SPAN class=braces>(</SPAN>str2binb<SPAN class=braces>(</SPAN>s<SPAN class=braces>)</SPAN>,s.<SPAN class=predefined_identifier>length</SPAN> * chrsz<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN><SPAN class=braces>}</SPAN>
<SPAN class=reserved_word>function</SPAN> b64_sha1<SPAN class=braces>(</SPAN>s<SPAN class=braces>)</SPAN><SPAN class=braces>{</SPAN><SPAN class=reserved_word>return</SPAN> binb2b64<SPAN class=braces>(</SPAN>core_sha1<SPAN class=braces>(</SPAN>str2binb<SPAN class=braces>(</SPAN>s<SPAN class=braces>)</SPAN>,s.<SPAN class=predefined_identifier>length</SPAN> * chrsz<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN><SPAN class=braces>}</SPAN>
<SPAN class=reserved_word>function</SPAN> str_sha1<SPAN class=braces>(</SPAN>s<SPAN class=braces>)</SPAN><SPAN class=braces>{</SPAN><SPAN class=reserved_word>return</SPAN> binb2str<SPAN class=braces>(</SPAN>core_sha1<SPAN class=braces>(</SPAN>str2binb<SPAN class=braces>(</SPAN>s<SPAN class=braces>)</SPAN>,s.<SPAN class=predefined_identifier>length</SPAN> * chrsz<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN><SPAN class=braces>}</SPAN>
<SPAN class=reserved_word>function</SPAN> hex_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN><SPAN class=braces>{</SPAN> <SPAN class=reserved_word>return</SPAN> binb2hex<SPAN class=braces>(</SPAN>core_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN><SPAN class=braces>}</SPAN>
<SPAN class=reserved_word>function</SPAN> b64_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN><SPAN class=braces>{</SPAN> <SPAN class=reserved_word>return</SPAN> binb2b64<SPAN class=braces>(</SPAN>core_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN><SPAN class=braces>}</SPAN>
<SPAN class=reserved_word>function</SPAN> str_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN><SPAN class=braces>{</SPAN> <SPAN class=reserved_word>return</SPAN> binb2str<SPAN class=braces>(</SPAN>core_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN><SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Perform a simple self-test to see if the VM is working
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> sha1_vm_test<SPAN class=braces>(</SPAN><SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>return</SPAN> hex_sha1<SPAN class=braces>(</SPAN><SPAN class=string>"abc"</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>=</SPAN><SPAN class=symbol>=</SPAN> <SPAN class=string>"a9993e364706816aba3e25717850c26c9cd0d89d"</SPAN><SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Calculate the SHA-1 of an array of big-endian words, and a bit length
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> core_sha1<SPAN class=braces>(</SPAN>x, len<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=comment>/* append padding */</SPAN>
 x[len <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>5</SPAN>] <SPAN class=symbol>|</SPAN><SPAN class=symbol>=</SPAN> <SPAN class=numeric>0x80</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> <SPAN class=braces>(</SPAN><SPAN class=numeric>24</SPAN> - len % <SPAN class=numeric>32</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 x[<SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>len + <SPAN class=numeric>64</SPAN> <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>9</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> <SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN> + <SPAN class=numeric>15</SPAN>] <SPAN class=symbol>=</SPAN> len<SPAN class=symbol>;</SPAN>

 <SPAN class=reserved_word>var</SPAN> w <SPAN class=symbol>=</SPAN> <SPAN class=predefined_type>Array</SPAN><SPAN class=braces>(</SPAN><SPAN class=numeric>80</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> a <SPAN class=symbol>=</SPAN> <SPAN class=numeric>1732584193</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> b <SPAN class=symbol>=</SPAN> -<SPAN class=numeric>271733879</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> c <SPAN class=symbol>=</SPAN> -<SPAN class=numeric>1732584194</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> d <SPAN class=symbol>=</SPAN> <SPAN class=numeric>271733878</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> e <SPAN class=symbol>=</SPAN> -<SPAN class=numeric>1009589776</SPAN><SPAN class=symbol>;</SPAN>

 <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> i <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> i <SPAN class=symbol><</SPAN> x.<SPAN class=predefined_identifier>length</SPAN><SPAN class=symbol>;</SPAN> i +<SPAN class=symbol>=</SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN>
 <SPAN class=braces>{</SPAN>
  <SPAN class=reserved_word>var</SPAN> olda <SPAN class=symbol>=</SPAN> a<SPAN class=symbol>;</SPAN>
  <SPAN class=reserved_word>var</SPAN> oldb <SPAN class=symbol>=</SPAN> b<SPAN class=symbol>;</SPAN>
  <SPAN class=reserved_word>var</SPAN> oldc <SPAN class=symbol>=</SPAN> c<SPAN class=symbol>;</SPAN>
  <SPAN class=reserved_word>var</SPAN> oldd <SPAN class=symbol>=</SPAN> d<SPAN class=symbol>;</SPAN>
  <SPAN class=reserved_word>var</SPAN> olde <SPAN class=symbol>=</SPAN> e<SPAN class=symbol>;</SPAN>

  <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> j <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> j <SPAN class=symbol><</SPAN> <SPAN class=numeric>80</SPAN><SPAN class=symbol>;</SPAN> j++<SPAN class=braces>)</SPAN>
  <SPAN class=braces>{</SPAN>
   <SPAN class=reserved_word>if</SPAN><SPAN class=braces>(</SPAN>j <SPAN class=symbol><</SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN> w[j] <SPAN class=symbol>=</SPAN> x[i + j]<SPAN class=symbol>;</SPAN>
   <SPAN class=reserved_word>else</SPAN> w[j] <SPAN class=symbol>=</SPAN> rol<SPAN class=braces>(</SPAN>w[j-<SPAN class=numeric>3</SPAN>] ^ w[j-<SPAN class=numeric>8</SPAN>] ^ w[j-<SPAN class=numeric>14</SPAN>] ^ w[j-<SPAN class=numeric>16</SPAN>], <SPAN class=numeric>1</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
   <SPAN class=reserved_word>var</SPAN> t <SPAN class=symbol>=</SPAN> safe_add<SPAN class=braces>(</SPAN>safe_add<SPAN class=braces>(</SPAN>rol<SPAN class=braces>(</SPAN>a, <SPAN class=numeric>5</SPAN><SPAN class=braces>)</SPAN>, sha1_ft<SPAN class=braces>(</SPAN>j, b, c, d<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN>,
            safe_add<SPAN class=braces>(</SPAN>safe_add<SPAN class=braces>(</SPAN>e, w[j]<SPAN class=braces>)</SPAN>, sha1_kt<SPAN class=braces>(</SPAN>j<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
   e <SPAN class=symbol>=</SPAN> d<SPAN class=symbol>;</SPAN>
   d <SPAN class=symbol>=</SPAN> c<SPAN class=symbol>;</SPAN>
   c <SPAN class=symbol>=</SPAN> rol<SPAN class=braces>(</SPAN>b, <SPAN class=numeric>30</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
   b <SPAN class=symbol>=</SPAN> a<SPAN class=symbol>;</SPAN>
   a <SPAN class=symbol>=</SPAN> t<SPAN class=symbol>;</SPAN>
  <SPAN class=braces>}</SPAN>

  a <SPAN class=symbol>=</SPAN> safe_add<SPAN class=braces>(</SPAN>a, olda<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
  b <SPAN class=symbol>=</SPAN> safe_add<SPAN class=braces>(</SPAN>b, oldb<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
  c <SPAN class=symbol>=</SPAN> safe_add<SPAN class=braces>(</SPAN>c, oldc<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
  d <SPAN class=symbol>=</SPAN> safe_add<SPAN class=braces>(</SPAN>d, oldd<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
  e <SPAN class=symbol>=</SPAN> safe_add<SPAN class=braces>(</SPAN>e, olde<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=braces>}</SPAN>
 <SPAN class=reserved_word>return</SPAN> <SPAN class=predefined_type>Array</SPAN><SPAN class=braces>(</SPAN>a, b, c, d, e<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>

<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Perform the appropriate triplet combination function for the current
 * iteration
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> sha1_ft<SPAN class=braces>(</SPAN>t, b, c, d<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>if</SPAN><SPAN class=braces>(</SPAN>t <SPAN class=symbol><</SPAN> <SPAN class=numeric>20</SPAN><SPAN class=braces>)</SPAN> <SPAN class=reserved_word>return</SPAN> <SPAN class=braces>(</SPAN>b <SPAN class=symbol>&</SPAN> c<SPAN class=braces>)</SPAN> <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>~b<SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> d<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>if</SPAN><SPAN class=braces>(</SPAN>t <SPAN class=symbol><</SPAN> <SPAN class=numeric>40</SPAN><SPAN class=braces>)</SPAN> <SPAN class=reserved_word>return</SPAN> b ^ c ^ d<SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>if</SPAN><SPAN class=braces>(</SPAN>t <SPAN class=symbol><</SPAN> <SPAN class=numeric>60</SPAN><SPAN class=braces>)</SPAN> <SPAN class=reserved_word>return</SPAN> <SPAN class=braces>(</SPAN>b <SPAN class=symbol>&</SPAN> c<SPAN class=braces>)</SPAN> <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN>b <SPAN class=symbol>&</SPAN> d<SPAN class=braces>)</SPAN> <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN>c <SPAN class=symbol>&</SPAN> d<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>return</SPAN> b ^ c ^ d<SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Determine the appropriate additive constant for the current iteration
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> sha1_kt<SPAN class=braces>(</SPAN>t<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>return</SPAN> <SPAN class=braces>(</SPAN>t <SPAN class=symbol><</SPAN> <SPAN class=numeric>20</SPAN><SPAN class=braces>)</SPAN> ? <SPAN class=numeric>1518500249</SPAN> : <SPAN class=braces>(</SPAN>t <SPAN class=symbol><</SPAN> <SPAN class=numeric>40</SPAN><SPAN class=braces>)</SPAN> ? <SPAN class=numeric>1859775393</SPAN> :
     <SPAN class=braces>(</SPAN>t <SPAN class=symbol><</SPAN> <SPAN class=numeric>60</SPAN><SPAN class=braces>)</SPAN> ? -<SPAN class=numeric>1894007588</SPAN> : -<SPAN class=numeric>899497514</SPAN><SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Calculate the HMAC-SHA1 of a key and some data
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> core_hmac_sha1<SPAN class=braces>(</SPAN>key, data<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>var</SPAN> bkey <SPAN class=symbol>=</SPAN> str2binb<SPAN class=braces>(</SPAN>key<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>if</SPAN><SPAN class=braces>(</SPAN>bkey.<SPAN class=predefined_identifier>length</SPAN> <SPAN class=symbol>></SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN> bkey <SPAN class=symbol>=</SPAN> core_sha1<SPAN class=braces>(</SPAN>bkey, key.<SPAN class=predefined_identifier>length</SPAN> * chrsz<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>

 <SPAN class=reserved_word>var</SPAN> ipad <SPAN class=symbol>=</SPAN> <SPAN class=predefined_type>Array</SPAN><SPAN class=braces>(</SPAN><SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN>, opad <SPAN class=symbol>=</SPAN> <SPAN class=predefined_type>Array</SPAN><SPAN class=braces>(</SPAN><SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> i <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> i <SPAN class=symbol><</SPAN> <SPAN class=numeric>16</SPAN><SPAN class=symbol>;</SPAN> i++<SPAN class=braces>)</SPAN>
 <SPAN class=braces>{</SPAN>
  ipad[i] <SPAN class=symbol>=</SPAN> bkey[i] ^ <SPAN class=numeric>0x36363636</SPAN><SPAN class=symbol>;</SPAN>
  opad[i] <SPAN class=symbol>=</SPAN> bkey[i] ^ <SPAN class=numeric>0x5C5C5C5C</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=braces>}</SPAN>

 <SPAN class=reserved_word>var</SPAN> <SPAN class=predefined_identifier>hash</SPAN> <SPAN class=symbol>=</SPAN> core_sha1<SPAN class=braces>(</SPAN>ipad.concat<SPAN class=braces>(</SPAN>str2binb<SPAN class=braces>(</SPAN>data<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN>, <SPAN class=numeric>512</SPAN> + data.<SPAN class=predefined_identifier>length</SPAN> * chrsz<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>return</SPAN> core_sha1<SPAN class=braces>(</SPAN>opad.concat<SPAN class=braces>(</SPAN><SPAN class=predefined_identifier>hash</SPAN><SPAN class=braces>)</SPAN>, <SPAN class=numeric>512</SPAN> + <SPAN class=numeric>160</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 * to work around bugs in some JS interpreters.
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> safe_add<SPAN class=braces>(</SPAN>x, y<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>var</SPAN> lsw <SPAN class=symbol>=</SPAN> <SPAN class=braces>(</SPAN>x <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xFFFF</SPAN><SPAN class=braces>)</SPAN> + <SPAN class=braces>(</SPAN>y <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xFFFF</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> msw <SPAN class=symbol>=</SPAN> <SPAN class=braces>(</SPAN>x <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN> + <SPAN class=braces>(</SPAN>y <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN> + <SPAN class=braces>(</SPAN>lsw <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>return</SPAN> <SPAN class=braces>(</SPAN>msw <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN>lsw <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xFFFF</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Bitwise rotate a 32-bit number to the left.
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> rol<SPAN class=braces>(</SPAN>num, cnt<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>return</SPAN> <SPAN class=braces>(</SPAN>num <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> cnt<SPAN class=braces>)</SPAN> <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN>num <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=braces>(</SPAN><SPAN class=numeric>32</SPAN> - cnt<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Convert an 8-bit or 16-bit string to an array of big-endian words
 * In 8-bit function, characters >255 have their hi-byte silently ignored.
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> str2binb<SPAN class=braces>(</SPAN>str<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>var</SPAN> bin <SPAN class=symbol>=</SPAN> <SPAN class=predefined_type>Array</SPAN><SPAN class=braces>(</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> mask <SPAN class=symbol>=</SPAN> <SPAN class=braces>(</SPAN><SPAN class=numeric>1</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> chrsz<SPAN class=braces>)</SPAN> - <SPAN class=numeric>1</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> i <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> i <SPAN class=symbol><</SPAN> str.<SPAN class=predefined_identifier>length</SPAN> * chrsz<SPAN class=symbol>;</SPAN> i +<SPAN class=symbol>=</SPAN> chrsz<SPAN class=braces>)</SPAN>
  bin[i<SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN><SPAN class=numeric>5</SPAN>] <SPAN class=symbol>|</SPAN><SPAN class=symbol>=</SPAN> <SPAN class=braces>(</SPAN>str.charCodeAt<SPAN class=braces>(</SPAN>i <SPAN class=symbol>/</SPAN> chrsz<SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> mask<SPAN class=braces>)</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> <SPAN class=braces>(</SPAN><SPAN class=numeric>32</SPAN> - chrsz - i%<SPAN class=numeric>32</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>return</SPAN> bin<SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Convert an array of big-endian words to a string
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> binb2str<SPAN class=braces>(</SPAN>bin<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>var</SPAN> str <SPAN class=symbol>=</SPAN> <SPAN class=string>""</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> mask <SPAN class=symbol>=</SPAN> <SPAN class=braces>(</SPAN><SPAN class=numeric>1</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> chrsz<SPAN class=braces>)</SPAN> - <SPAN class=numeric>1</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> i <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> i <SPAN class=symbol><</SPAN> bin.<SPAN class=predefined_identifier>length</SPAN> * <SPAN class=numeric>32</SPAN><SPAN class=symbol>;</SPAN> i +<SPAN class=symbol>=</SPAN> chrsz<SPAN class=braces>)</SPAN>
  str +<SPAN class=symbol>=</SPAN> String.fromCharCode<SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>bin[i<SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN><SPAN class=numeric>5</SPAN>] <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=braces>(</SPAN><SPAN class=numeric>32</SPAN> - chrsz - i%<SPAN class=numeric>32</SPAN><SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> mask<SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>return</SPAN> str<SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Convert an array of big-endian words to a hex string.
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> binb2hex<SPAN class=braces>(</SPAN>binarray<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>var</SPAN> hex_tab <SPAN class=symbol>=</SPAN> hexcase ? <SPAN class=string>"0123456789ABCDEF"</SPAN> : <SPAN class=string>"0123456789abcdef"</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> str <SPAN class=symbol>=</SPAN> <SPAN class=string>""</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> i <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> i <SPAN class=symbol><</SPAN> binarray.<SPAN class=predefined_identifier>length</SPAN> * <SPAN class=numeric>4</SPAN><SPAN class=symbol>;</SPAN> i++<SPAN class=braces>)</SPAN>
 <SPAN class=braces>{</SPAN>
  str +<SPAN class=symbol>=</SPAN> hex_tab.<SPAN class=library_function>charAt</SPAN><SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>binarray[i<SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN><SPAN class=numeric>2</SPAN>] <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN><SPAN class=numeric>3</SPAN> - i%<SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN>*<SPAN class=numeric>8</SPAN>+<SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xF</SPAN><SPAN class=braces>)</SPAN> +
      hex_tab.<SPAN class=library_function>charAt</SPAN><SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>binarray[i<SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN><SPAN class=numeric>2</SPAN>] <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN><SPAN class=numeric>3</SPAN> - i%<SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN>*<SPAN class=numeric>8</SPAN> <SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xF</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=braces>}</SPAN>
 <SPAN class=reserved_word>return</SPAN> str<SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>

<SPAN class=comment>/*
 * Convert an array of big-endian words to a base-64 string
 */</SPAN>
<SPAN class=reserved_word>function</SPAN> binb2b64<SPAN class=braces>(</SPAN>binarray<SPAN class=braces>)</SPAN>
<SPAN class=braces>{</SPAN>
 <SPAN class=reserved_word>var</SPAN> tab <SPAN class=symbol>=</SPAN> <SPAN class=string>"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>var</SPAN> str <SPAN class=symbol>=</SPAN> <SPAN class=string>""</SPAN><SPAN class=symbol>;</SPAN>
 <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> i <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> i <SPAN class=symbol><</SPAN> binarray.<SPAN class=predefined_identifier>length</SPAN> * <SPAN class=numeric>4</SPAN><SPAN class=symbol>;</SPAN> i +<SPAN class=symbol>=</SPAN> <SPAN class=numeric>3</SPAN><SPAN class=braces>)</SPAN>
 <SPAN class=braces>{</SPAN>
  <SPAN class=reserved_word>var</SPAN> triplet <SPAN class=symbol>=</SPAN> <SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>binarray[i  <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>2</SPAN>] <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>8</SPAN> * <SPAN class=braces>(</SPAN><SPAN class=numeric>3</SPAN> - i  %<SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xFF</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> <SPAN class=numeric>16</SPAN><SPAN class=braces>)</SPAN>
        <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>binarray[i+<SPAN class=numeric>1</SPAN> <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>2</SPAN>] <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>8</SPAN> * <SPAN class=braces>(</SPAN><SPAN class=numeric>3</SPAN> - <SPAN class=braces>(</SPAN>i+<SPAN class=numeric>1</SPAN><SPAN class=braces>)</SPAN>%<SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xFF</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol><</SPAN><SPAN class=symbol><</SPAN> <SPAN class=numeric>8</SPAN> <SPAN class=braces>)</SPAN>
        <SPAN class=symbol>|</SPAN> <SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>binarray[i+<SPAN class=numeric>2</SPAN> <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>2</SPAN>] <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>8</SPAN> * <SPAN class=braces>(</SPAN><SPAN class=numeric>3</SPAN> - <SPAN class=braces>(</SPAN>i+<SPAN class=numeric>2</SPAN><SPAN class=braces>)</SPAN>%<SPAN class=numeric>4</SPAN><SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0xFF</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
  <SPAN class=reserved_word>for</SPAN><SPAN class=braces>(</SPAN><SPAN class=reserved_word>var</SPAN> j <SPAN class=symbol>=</SPAN> <SPAN class=numeric>0</SPAN><SPAN class=symbol>;</SPAN> j <SPAN class=symbol><</SPAN> <SPAN class=numeric>4</SPAN><SPAN class=symbol>;</SPAN> j++<SPAN class=braces>)</SPAN>
  <SPAN class=braces>{</SPAN>
   <SPAN class=reserved_word>if</SPAN><SPAN class=braces>(</SPAN>i * <SPAN class=numeric>8</SPAN> + j * <SPAN class=numeric>6</SPAN> <SPAN class=symbol>></SPAN> binarray.<SPAN class=predefined_identifier>length</SPAN> * <SPAN class=numeric>32</SPAN><SPAN class=braces>)</SPAN> str +<SPAN class=symbol>=</SPAN> b64pad<SPAN class=symbol>;</SPAN>
   <SPAN class=reserved_word>else</SPAN> str +<SPAN class=symbol>=</SPAN> tab.<SPAN class=library_function>charAt</SPAN><SPAN class=braces>(</SPAN><SPAN class=braces>(</SPAN>triplet <SPAN class=symbol>></SPAN><SPAN class=symbol>></SPAN> <SPAN class=numeric>6</SPAN>*<SPAN class=braces>(</SPAN><SPAN class=numeric>3</SPAN>-j<SPAN class=braces>)</SPAN><SPAN class=braces>)</SPAN> <SPAN class=symbol>&</SPAN> <SPAN class=numeric>0x3F</SPAN><SPAN class=braces>)</SPAN><SPAN class=symbol>;</SPAN>
  <SPAN class=braces>}</SPAN>
 <SPAN class=braces>}</SPAN>
 <SPAN class=reserved_word>return</SPAN> str<SPAN class=symbol>;</SPAN>
<SPAN class=braces>}</SPAN>
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