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 <span id="projectnumber">2.3.4</span>
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<div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno"> 1</span><span class="comment">/*= -*- c-basic-offset: 4; indent-tabs-mode: nil; -*-</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno"> 2</span><span class="comment"> *</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno"> 3</span><span class="comment"> * librsync -- the library for network deltas</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno"> 4</span><span class="comment"> *</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno"> 5</span><span class="comment"> * Copyright (C) 1999, 2000, 2001 by Martin Pool <[email protected]></span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno"> 6</span><span class="comment"> * Copyright (C) 1996 by Andrew Tridgell</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno"> 7</span><span class="comment"> * Copyright (C) 1996 by Paul Mackerras</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno"> 8</span><span class="comment"> *</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno"> 9</span><span class="comment"> * This program is free software; you can redistribute it and/or modify</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno"> 10</span><span class="comment"> * it under the terms of the GNU Lesser General Public License as published by</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno"> 11</span><span class="comment"> * the Free Software Foundation; either version 2.1 of the License, or</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno"> 12</span><span class="comment"> * (at your option) any later version.</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno"> 13</span><span class="comment"> *</span></div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno"> 14</span><span class="comment"> * This program is distributed in the hope that it will be useful,</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno"> 15</span><span class="comment"> * but WITHOUT ANY WARRANTY; without even the implied warranty of</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno"> 16</span><span class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</span></div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno"> 17</span><span class="comment"> * GNU Lesser General Public License for more details.</span></div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno"> 18</span><span class="comment"> *</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno"> 19</span><span class="comment"> * You should have received a copy of the GNU Lesser General Public License</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno"> 20</span><span class="comment"> * along with this program; if not, write to the Free Software</span></div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno"> 21</span><span class="comment"> * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.</span></div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno"> 22</span><span class="comment"> */</span></div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno"> 23</span> </div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno"> 24</span><span class="preprocessor">#include "config.h"</span> <span class="comment">/* IWYU pragma: keep */</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno"> 25</span><span class="preprocessor">#include <stdint.h></span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno"> 26</span><span class="preprocessor">#include "<a class="code" href="checksum_8h.html">checksum.h</a>"</span></div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno"> 27</span><span class="preprocessor">#include "blake2.h"</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno"> 28</span><span class="preprocessor">#include "librsync_export.h"</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno"> 29</span> </div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno"> 30</span>LIBRSYNC_EXPORT <span class="keyword">const</span> <span class="keywordtype">int</span> RS_MD4_SUM_LENGTH = 16;</div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno"> 31</span>LIBRSYNC_EXPORT <span class="keyword">const</span> <span class="keywordtype">int</span> RS_BLAKE2_SUM_LENGTH = 32;</div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno"> 32</span><span class="comment"></span> </div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno"> 33</span><span class="comment">/** A simple 32bit checksum that can be incrementally updated. */</span></div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno"><a class="line" href="checksum_8h.html#a25c2d070f333e27ee30831f05bc77c65"> 34</a></span>rs_weak_sum_t <a class="code hl_function" href="checksum_8h.html#a25c2d070f333e27ee30831f05bc77c65">rs_calc_weak_sum</a>(<a class="code hl_enumeration" href="checksum_8h.html#a523b170a7d10ae0b00117c2761abaf8d">weaksum_kind_t</a> kind, <span class="keywordtype">void</span> <span class="keyword">const</span> *buf, <span class="keywordtype">size_t</span> len)</div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno"> 35</span>{</div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno"> 36</span> <span class="keywordflow">if</span> (kind == RS_ROLLSUM) {</div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno"> 37</span> <a class="code hl_struct" href="structRollsum.html">Rollsum</a> sum;</div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno"> 38</span> RollsumInit(&sum);</div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno"> 39</span> RollsumUpdate(&sum, buf, len);</div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno"> 40</span> <span class="keywordflow">return</span> RollsumDigest(&sum);</div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno"> 41</span> } <span class="keywordflow">else</span> {</div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno"> 42</span> <a class="code hl_struct" href="structrabinkarp.html">rabinkarp_t</a> sum;</div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno"> 43</span> rabinkarp_init(&sum);</div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno"> 44</span> rabinkarp_update(&sum, buf, len);</div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno"> 45</span> <span class="keywordflow">return</span> rabinkarp_digest(&sum);</div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno"> 46</span> }</div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno"> 47</span>}</div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno"> 48</span><span class="comment"></span> </div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno"> 49</span><span class="comment">/** Calculate and store into SUM a strong checksum.</span></div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno"> 50</span><span class="comment"> *</span></div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno"> 51</span><span class="comment"> * In plain rsync, the checksum is perturbed by a seed value. This is used when</span></div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno"> 52</span><span class="comment"> * retrying a failed transmission: we've discovered that the hashes collided at</span></div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno"> 53</span><span class="comment"> * some point, so we're going to try again with different hashes to see if we</span></div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno"> 54</span><span class="comment"> * can get it right. (Check tridge's thesis for details and to see if that's</span></div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno"> 55</span><span class="comment"> * correct.)</span></div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno"> 56</span><span class="comment"> *</span></div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno"> 57</span><span class="comment"> * Since we can't retry I'm not sure if it's very useful for librsync, except</span></div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno"> 58</span><span class="comment"> * perhaps as protection against hash collision attacks. */</span></div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno"><a class="line" href="checksum_8h.html#aca0ef7069e47972313f74f66d9c29298"> 59</a></span><span class="keywordtype">void</span> <a class="code hl_function" href="checksum_8h.html#aca0ef7069e47972313f74f66d9c29298">rs_calc_strong_sum</a>(<a class="code hl_enumeration" href="checksum_8h.html#a358cb59b26ba2585bc2094b4da2a547d">strongsum_kind_t</a> kind, <span class="keywordtype">void</span> <span class="keyword">const</span> *buf, <span class="keywordtype">size_t</span> len,</div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno"> 60</span> rs_strong_sum_t *sum)</div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno"> 61</span>{</div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno"> 62</span> <span class="keywordflow">if</span> (kind == RS_MD4) {</div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno"> 63</span> <a class="code hl_struct" href="structrs__mdfour.html">rs_mdfour</a>((<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> *)sum, buf, len);</div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno"> 64</span> } <span class="keywordflow">else</span> {</div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno"> 65</span> blake2b_state ctx;</div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno"> 66</span> blake2b_init(&ctx, RS_MAX_STRONG_SUM_LENGTH);</div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno"> 67</span> blake2b_update(&ctx, (<span class="keyword">const</span> uint8_t *)buf, len);</div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno"> 68</span> blake2b_final(&ctx, (uint8_t *)sum, RS_MAX_STRONG_SUM_LENGTH);</div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno"> 69</span> }</div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno"> 70</span>}</div>
<div class="ttc" id="achecksum_8h_html"><div class="ttname"><a href="checksum_8h.html">checksum.h</a></div><div class="ttdoc">Abstract wrappers around different weaksum and strongsum implementations.</div></div>
<div class="ttc" id="achecksum_8h_html_a25c2d070f333e27ee30831f05bc77c65"><div class="ttname"><a href="checksum_8h.html#a25c2d070f333e27ee30831f05bc77c65">rs_calc_weak_sum</a></div><div class="ttdeci">rs_weak_sum_t rs_calc_weak_sum(weaksum_kind_t kind, void const *buf, size_t len)</div><div class="ttdoc">Calculate a weaksum.</div><div class="ttdef"><b>Definition:</b> <a href="checksum_8c_source.html#l00034">checksum.c:34</a></div></div>
<div class="ttc" id="achecksum_8h_html_a358cb59b26ba2585bc2094b4da2a547d"><div class="ttname"><a href="checksum_8h.html#a358cb59b26ba2585bc2094b4da2a547d">strongsum_kind_t</a></div><div class="ttdeci">strongsum_kind_t</div><div class="ttdoc">Strongsum implementations.</div><div class="ttdef"><b>Definition:</b> <a href="checksum_8h_source.html#l00041">checksum.h:41</a></div></div>
<div class="ttc" id="achecksum_8h_html_a523b170a7d10ae0b00117c2761abaf8d"><div class="ttname"><a href="checksum_8h.html#a523b170a7d10ae0b00117c2761abaf8d">weaksum_kind_t</a></div><div class="ttdeci">weaksum_kind_t</div><div class="ttdoc">Weaksum implementations.</div><div class="ttdef"><b>Definition:</b> <a href="checksum_8h_source.html#l00035">checksum.h:35</a></div></div>
<div class="ttc" id="achecksum_8h_html_aca0ef7069e47972313f74f66d9c29298"><div class="ttname"><a href="checksum_8h.html#aca0ef7069e47972313f74f66d9c29298">rs_calc_strong_sum</a></div><div class="ttdeci">void rs_calc_strong_sum(strongsum_kind_t kind, void const *buf, size_t len, rs_strong_sum_t *sum)</div><div class="ttdoc">Calculate a strongsum.</div><div class="ttdef"><b>Definition:</b> <a href="checksum_8c_source.html#l00059">checksum.c:59</a></div></div>
<div class="ttc" id="astructRollsum_html"><div class="ttname"><a href="structRollsum.html">Rollsum</a></div><div class="ttdoc">The Rollsum state type.</div><div class="ttdef"><b>Definition:</b> <a href="rollsum_8h_source.html#l00036">rollsum.h:36</a></div></div>
<div class="ttc" id="astructrabinkarp_html"><div class="ttname"><a href="structrabinkarp.html">rabinkarp</a></div><div class="ttdoc">The rabinkarp_t state type.</div><div class="ttdef"><b>Definition:</b> <a href="rabinkarp_8h_source.html#l00056">rabinkarp.h:56</a></div></div>
<div class="ttc" id="astructrs__mdfour_html"><div class="ttname"><a href="structrs__mdfour.html">rs_mdfour</a></div><div class="ttdoc">The rs_mdfour state type.</div><div class="ttdef"><b>Definition:</b> <a href="mdfour_8h_source.html#l00046">mdfour.h:46</a></div></div>
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