Add md5sum in lsb, combine sha1sum (mostly shared infrastructure). Downside: current infrastructure can't give them different help text. Hmmm...

1 files changed, 239 insertions, 0 deletions

diff --git a/toys/lsb/md5sum.c b/toys/lsb/md5sum.c
new file mode 100644
index 00000000..44bafb1f
--- /dev/null
+++ b/toys/lsb/md5sum.c
@@ -0,0 +1,239 @@
+/* vi: set sw=4 ts=4:
+ *
+ * md5sum.c - Calculate RFC 1321 md5 hash and sha1 hash.
+ *
+ * Copyright 2012 Rob Landley <rob@landley.net>
+ *
+ * See http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/md5sum.html
+ * and http://www.ietf.org/rfc/rfc1321.txt
+ *
+ * They're combined this way to share infrastructure, and because md5sum is
+ * and LSB standard command, sha1sum is just a good idea.
+
+USE_MD5SUM(NEWTOY(md5sum, NULL, TOYFLAG_USR|TOYFLAG_BIN))
+USE_MD5SUM_SHA1SUM(OLDTOY(sha1sum, md5sum, NULL, TOYFLAG_USR|TOYFLAG_BIN))
+
+config MD5SUM
+  bool "md5sum"
+  default n
+  help
+    usage: md5sum [FILE]...
+
+    Calculate md5 hash for each input file, reading from stdin if none.
+    Output one hash (16 hex digits) for each input file, followed by
+    filename.
+
+config MD5SUM_SHA1SUM
+  bool "sha1sum"
+  depends on MD5SUM
+  help
+    usage: sha1sum [FILE]...
+
+    calculate sha1 hash for each input file, reading from stdin if one.
+    Output one hash (20 hex digits) for each input file, followed by
+    filename.
+*/
+
+#define FOR_md5sum
+#include "toys.h"
+
+GLOBALS(
+  unsigned state[5];
+  unsigned oldstate[5];
+  uint64_t count;
+  union {
+    char c[64];
+    unsigned i[16];
+  } buffer;
+)
+
+// for(i=0; i<64; i++) md5table[i] = abs(sin(i+1))*(1<<32);  But calculating
+// that involves not just floating point but pulling in -lm (and arguing with
+// C about whether 1<<32 is a valid thing to do on 32 bit platforms) so:
+
+static uint32_t md5table[64] = {
+  0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, 0xf57c0faf, 0x4787c62a,
+  0xa8304613, 0xfd469501, 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
+  0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, 0xf61e2562, 0xc040b340,
+  0x265e5a51, 0xe9b6c7aa, 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
+  0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, 0xa9e3e905, 0xfcefa3f8,
+  0x676f02d9, 0x8d2a4c8a, 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
+  0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, 0x289b7ec6, 0xeaa127fa,
+  0xd4ef3085, 0x04881d05, 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
+  0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, 0x655b59c3, 0x8f0ccc92,
+  0xffeff47d, 0x85845dd1, 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
+  0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
+};
+
+// Mix next 64 bytes of data into md5 hash
+
+static void md5_transform(void)
+{
+  unsigned x[4], *b = (unsigned *)TT.buffer.c;
+  int i;
+
+  memcpy(x, TT.state, sizeof(x));
+
+  for (i=0; i<64; i++) {
+    unsigned int in, a, rot, temp;
+
+    a = (-i)&3;
+    if (i<16) {
+      in = i;
+      rot = 7+(5*(i&3));
+      temp = x[(a+1)&3];
+      temp = (temp & x[(a+2)&3]) | ((~temp) & x[(a+3)&3]);
+    } else if (i<32) {
+      in = (1+(5*i))&15;
+      temp = (i&3)+1;
+      rot = temp*5;
+      if (temp&2) rot--;
+      temp = x[(a+3)&3];
+      temp = (x[(a+1)&3] & temp) | (x[(a+2)&3] & ~temp);
+    } else if (i<48) {
+      in = (5+(3*(i&15)))&15;
+      rot = i&3;
+      rot = 4+(5*rot)+((rot+1)&6);
+      temp = x[(a+1)&3] ^ x[(a+2)&3] ^ x[(a+3)&3];
+    } else {
+      in = (7*(i&15))&15;
+      rot = (i&3)+1;
+      rot = (5*rot)+(((rot+2)&2)>>1);
+      temp = x[(a+2)&3] ^ (x[(a+1)&3] | ~x[(a+3)&3]);
+    }
+    temp += x[a] + b[in] + md5table[i];
+    x[a] = x[(a+1)&3] + ((temp<<rot) | (temp>>(32-rot)));
+  }
+  for (i=0; i<4; i++) TT.state[i] += x[i];
+}
+
+// Mix next 64 bytes of data into sha1 hash.
+
+static const unsigned rconsts[]={0x5A827999,0x6ED9EBA1,0x8F1BBCDC,0xCA62C1D6};
+#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
+
+static void sha1_transform(void)
+{
+  int i, j, k, count;
+  unsigned *block = TT.buffer.i;
+  unsigned *rot[5], *temp;
+
+  // Copy context->state[] to working vars
+  for (i=0; i<5; i++) {
+    TT.oldstate[i] = TT.state[i];
+    rot[i] = TT.state + i;
+  }
+  // 4 rounds of 20 operations each.
+  for (i=count=0; i<4; i++) {
+    for (j=0; j<20; j++) {
+      unsigned work;
+
+      work = *rot[2] ^ *rot[3];
+      if (!i) work = (work & *rot[1]) ^ *rot[3];
+      else {
+        if (i==2) work = ((*rot[1]|*rot[2])&*rot[3])|(*rot[1]&*rot[2]);
+        else work ^= *rot[1];
+      }
+
+      if (!i && j<16)
+        work += block[count] = (rol(block[count],24)&0xFF00FF00)
+                             | (rol(block[count],8)&0x00FF00FF);
+      else
+        work += block[count&15] = rol(block[(count+13)&15]
+              ^ block[(count+8)&15] ^ block[(count+2)&15] ^ block[count&15], 1);
+      *rot[4] += work + rol(*rot[0],5) + rconsts[i];
+      *rot[1] = rol(*rot[1],30);
+
+      // Rotate by one for next time.
+      temp = rot[4];
+      for (k=4; k; k--) rot[k] = rot[k-1];
+      *rot = temp;
+      count++;
+    }
+  }
+  // Add the previous values of state[]
+  for (i=0; i<5; i++) TT.state[i] += TT.oldstate[i];
+}
+
+// Fill the 64-byte working buffer and call transform() when full.
+
+static void hash_update(char *data, unsigned int len, void (*transform)(void))
+{
+  unsigned int i, j;
+
+  j = TT.count & 63;
+  TT.count += len;
+
+  // Enough data to process a frame?
+  if ((j + len) > 63) {
+    i = 64-j;
+    memcpy(TT.buffer.c + j, data, i);
+    transform();
+    for ( ; i + 63 < len; i += 64) {
+      memcpy(TT.buffer.c, data + i, 64);
+      transform();
+    }
+    j = 0;
+  } else i = 0;
+  // Grab remaining chunk
+  memcpy(TT.buffer.c + j, data + i, len - i);
+}
+
+// Callback for loopfiles()
+
+static void do_hash(int fd, char *name)
+{
+  uint64_t count;
+  int i, sha1=toys.which->name[0]=='s';;
+  char buf;
+  void (*transform)(void);
+
+  /* SHA1 initialization constants  (md5sum uses first 4) */
+  TT.state[0] = 0x67452301;
+  TT.state[1] = 0xEFCDAB89;
+  TT.state[2] = 0x98BADCFE;
+  TT.state[3] = 0x10325476;
+  TT.state[4] = 0xC3D2E1F0;
+  TT.count = 0;
+
+  transform = sha1 ? sha1_transform : md5_transform;
+  for (;;) {
+    i = read(fd, toybuf, sizeof(toybuf));
+    if (i<1) break;
+    hash_update(toybuf, i, transform);
+  }
+
+  count = TT.count << 3;
+
+  // End the message by appending a "1" bit to the data, ending with the
+  // message size (in bits, big endian), and adding enough zero bits in
+  // between to pad to the end of the next 64-byte frame.
+  //
+  // Since our input up to now has been in whole bytes, we can deal with
+  // bytes here too.
+
+  buf = 0x80;
+  do {
+    hash_update(&buf, 1, transform);
+    buf = 0;
+  } while ((TT.count & 63) != 56);
+  if (sha1) count=bswap_64(count);
+  for (i = 0; i < 8; i++)
+    TT.buffer.c[56+i] = count >> (8*i);
+  transform();
+
+  if (sha1)
+    for (i = 0; i < 20; i++)
+      printf("%02x", 255&(TT.state[i>>2] >> ((3-(i & 3)) * 8)));
+  else for (i=0; i<4; i++) printf("%08x", SWAP_BE32(TT.state[i]));
+
+  // Wipe variables.  Cryptographer paranoia.
+  memset(&TT, 0, sizeof(TT));
+
+  printf("  %s\n", name);
+}
+
+void md5sum_main(void)
+{
+  loopfiles(toys.optargs, do_hash);
+}