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copied!<p>I have tested your code, and it works as it should:</p> <pre><code>for i in $( seq 1 100 ); do openssl rand 9000 | head -c 9000 > test YOUR=$( ./sha1 test | cut -b 12- ) SHA1=$( openssl dgst -sha1 test | cut -b 13- ) if [ "$YOUR" == "$SHA1" ]; then echo $YOUR OK else echo $YOUR $SHA1 FAIL fi done </code></pre> <p>Also works with lengths 8000, 9100, 10000.</p> <p>Tested your second code, this too appears to work correctly. This is the modified version I wrote to test on different files by supplying the name on command line:</p> <pre><code>#include <stdio.h> #include <openssl/sha.h> int main(int argc, char **argv) { unsigned char c[SHA_DIGEST_LENGTH]; int i; FILE *inFile = fopen (argv[1], "rb"); SHA_CTX shaContext; int bytes; unsigned char data[1024]; if (inFile == NULL) { printf ("%s can't be opened.\n", argv[1]); return 0; } SHA1_Init (&shaContext); while ((bytes = fread (data, 1, 1024, inFile)) != 0) { printf("Read %d bytes\n", bytes); SHA1_Update (&shaContext, data, bytes); } SHA1_Final (c,&shaContext); for(i = 0; i < SHA_DIGEST_LENGTH; i++) printf("%02x", c[i]); printf (" %s\n", argv[1]); fclose (inFile); return 0; } </code></pre> <p>There must be something in <em>how</em> the code is compiled that yields the wrong results.</p> <p>I checked with <code>gcc version 4.7.1 20120723 [gcc-4_7-branch revision 189773] (SUSE Linux)</code> on kernel 3.4.6 x86_64.</p> <p>I have modified the code above to print some information about its operation. I tested it with a file made up of 9000 zeroes (<code>dd if=/dev/zero of=/tmp/zeroes bs=1 count=9000</code>) and got:</p> <pre><code>Read 1024 bytes Read 1024 bytes Read 1024 bytes Read 1024 bytes Read 1024 bytes Read 1024 bytes Read 1024 bytes Read 1024 bytes Read 808 bytes 980eb7886d6d6ce206b9ce5371042d32c96d2714 /tmp/zeroes </code></pre> <p>If block sizes do match, then we'll try printing the sum of all bytes (which ought to be always zero), or check the buffer one byte at a time.</p> <p>If you have the same SHA1 as me, we'll try with a sequence of 9000 0x80's.</p>

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