Add SHA-224/256 and HMAC-SHA-224/256 crypto hash

1 files changed, 467 insertions, 0 deletions

diff --git a/lib/sha256.c b/lib/sha256.c
new file mode 100644
index 00000000..2d979f90
--- /dev/null
+++ b/lib/sha256.c
@@ -0,0 +1,467 @@
+/*
+ *	BIRD Library -- SHA-256 and SHA-224 Hash Functions,
+ *			HMAC-SHA-256 and HMAC-SHA-224 Functions
+ *
+ *	(c) 2015 CZ.NIC z.s.p.o.
+ *
+ *	Based on the code from libgcrypt-1.6.0, which is
+ *	(c) 2003, 2006, 2008, 2009 Free Software Foundation, Inc.
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#include "lib/sha256.h"
+#include "lib/unaligned.h"
+
+static uint sha256_transform(void *ctx, const byte *data, size_t nblks);
+
+void
+sha256_init(struct sha256_context *ctx)
+{
+  ctx->h0 = 0x6a09e667;
+  ctx->h1 = 0xbb67ae85;
+  ctx->h2 = 0x3c6ef372;
+  ctx->h3 = 0xa54ff53a;
+  ctx->h4 = 0x510e527f;
+  ctx->h5 = 0x9b05688c;
+  ctx->h6 = 0x1f83d9ab;
+  ctx->h7 = 0x5be0cd19;
+
+  ctx->nblocks = 0;
+  ctx->nblocks_high = 0;
+  ctx->count = 0;
+  ctx->blocksize = 64;
+  ctx->transform = sha256_transform;
+}
+
+void
+sha224_init(struct sha224_context *ctx)
+{
+  ctx->h0 = 0xc1059ed8;
+  ctx->h1 = 0x367cd507;
+  ctx->h2 = 0x3070dd17;
+  ctx->h3 = 0xf70e5939;
+  ctx->h4 = 0xffc00b31;
+  ctx->h5 = 0x68581511;
+  ctx->h6 = 0x64f98fa7;
+  ctx->h7 = 0xbefa4fa4;
+
+  ctx->nblocks = 0;
+  ctx->nblocks_high = 0;
+  ctx->count = 0;
+  ctx->blocksize = 64;
+  ctx->transform = sha256_transform;
+}
+
+/* (4.2) same as SHA-1's F1.  */
+static inline u32
+f1(u32 x, u32 y, u32 z)
+{
+  return (z ^ (x & (y ^ z)));
+}
+
+/* (4.3) same as SHA-1's F3 */
+static inline u32
+f3(u32 x, u32 y, u32 z)
+{
+  return ((x & y) | (z & (x|y)));
+}
+
+/* Bitwise rotation of an uint to the right */
+static inline u32 ror(u32 x, int n)
+{
+  return ( (x >> (n&(32-1))) | (x << ((32-n)&(32-1))) );
+}
+
+/* (4.4) */
+static inline u32
+sum0(u32 x)
+{
+  return (ror(x, 2) ^ ror(x, 13) ^ ror(x, 22));
+}
+
+/* (4.5) */
+static inline u32
+sum1(u32 x)
+{
+  return (ror(x, 6) ^ ror(x, 11) ^ ror(x, 25));
+}
+
+/*
+  Transform the message X which consists of 16 32-bit-words. See FIPS
+  180-2 for details.  */
+#define S0(x) (ror((x),  7) ^ ror((x), 18) ^ ((x) >>  3))	/* (4.6) */
+#define S1(x) (ror((x), 17) ^ ror((x), 19) ^ ((x) >> 10))	/* (4.7) */
+#define R(a,b,c,d,e,f,g,h,k,w)					\
+    do								\
+    {								\
+      t1 = (h) + sum1((e)) + f1((e),(f),(g)) + (k) + (w);	\
+      t2 = sum0((a)) + f3((a),(b),(c));				\
+      h = g;							\
+      g = f;							\
+      f = e;							\
+      e = d + t1;						\
+      d = c;							\
+      c = b;							\
+      b = a;							\
+      a = t1 + t2;						\
+    } while (0)
+
+/*
+    The SHA-256 core: Transform the message X which consists of 16
+    32-bit-words. See FIPS 180-2 for details.
+ */
+static uint
+sha256_transform_block(struct sha256_context *ctx, const byte *data)
+{
+  static const u32 K[64] = {
+      0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+      0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+      0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+      0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+      0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+      0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+      0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+      0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+      0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+      0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+      0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+      0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+      0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+      0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+      0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+      0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+  };
+
+  u32 a,b,c,d,e,f,g,h,t1,t2;
+  u32 w[64];
+  int i;
+
+  a = ctx->h0;
+  b = ctx->h1;
+  c = ctx->h2;
+  d = ctx->h3;
+  e = ctx->h4;
+  f = ctx->h5;
+  g = ctx->h6;
+  h = ctx->h7;
+
+  for (i = 0; i < 16; i++)
+    w[i] = get_u32(data + i * 4);
+  for (; i < 64; i++)
+    w[i] = S1(w[i-2]) + w[i-7] + S0(w[i-15]) + w[i-16];
+
+  for (i = 0; i < 64;)
+  {
+    t1 = h + sum1(e) + f1(e, f, g) + K[i] + w[i];
+    t2 = sum0 (a) + f3(a, b, c);
+    d += t1;
+    h  = t1 + t2;
+
+    t1 = g + sum1(d) + f1(d, e, f) + K[i+1] + w[i+1];
+    t2 = sum0 (h) + f3(h, a, b);
+    c += t1;
+    g  = t1 + t2;
+
+    t1 = f + sum1(c) + f1(c, d, e) + K[i+2] + w[i+2];
+    t2 = sum0 (g) + f3(g, h, a);
+    b += t1;
+    f  = t1 + t2;
+
+    t1 = e + sum1(b) + f1(b, c, d) + K[i+3] + w[i+3];
+    t2 = sum0 (f) + f3(f, g, h);
+    a += t1;
+    e  = t1 + t2;
+
+    t1 = d + sum1(a) + f1(a, b, c) + K[i+4] + w[i+4];
+    t2 = sum0 (e) + f3(e, f, g);
+    h += t1;
+    d  = t1 + t2;
+
+    t1 = c + sum1(h) + f1(h, a, b) + K[i+5] + w[i+5];
+    t2 = sum0 (d) + f3(d, e, f);
+    g += t1;
+    c  = t1 + t2;
+
+    t1 = b + sum1(g) + f1(g, h, a) + K[i+6] + w[i+6];
+    t2 = sum0 (c) + f3(c, d, e);
+    f += t1;
+    b  = t1 + t2;
+
+    t1 = a + sum1(f) + f1(f, g, h) + K[i+7] + w[i+7];
+    t2 = sum0 (b) + f3(b, c, d);
+    e += t1;
+    a  = t1 + t2;
+
+    i += 8;
+  }
+
+  ctx->h0 += a;
+  ctx->h1 += b;
+  ctx->h2 += c;
+  ctx->h3 += d;
+  ctx->h4 += e;
+  ctx->h5 += f;
+  ctx->h6 += g;
+  ctx->h7 += h;
+
+  return /*burn_stack*/ 74*4+32;
+}
+#undef S0
+#undef S1
+#undef R
+
+static uint
+sha256_transform(void *ctx, const byte *data, size_t nblks)
+{
+  struct sha256_context *hd = ctx;
+  uint burn;
+
+  do
+  {
+    burn = sha256_transform_block(hd, data);
+    data += 64;
+  }
+  while (--nblks);
+
+  return burn;
+}
+
+/* Common function to write a chunk of data to the transform function
+   of a hash algorithm.  Note that the use of the term "block" does
+   not imply a fixed size block.  Note that we explicitly allow to use
+   this function after the context has been finalized; the result does
+   not have any meaning but writing after finalize is sometimes
+   helpful to mitigate timing attacks. */
+void
+sha256_update(struct sha256_context *ctx, const byte *in_buf, size_t in_len)
+{
+  const uint blocksize = ctx->blocksize;
+  size_t inblocks;
+
+  if (sizeof(ctx->buf) < blocksize)
+    debug("BUG: in file %s at line %d", __FILE__ , __LINE__);
+
+  if (ctx->count == blocksize)  /* Flush the buffer. */
+  {
+    ctx->transform(ctx, ctx->buf, 1);
+    ctx->count = 0;
+    if (!++ctx->nblocks)
+      ctx->nblocks_high++;
+  }
+  if (!in_buf)
+    return;
+
+  if (ctx->count)
+  {
+    for (; in_len && ctx->count < blocksize; in_len--)
+      ctx->buf[ctx->count++] = *in_buf++;
+    sha256_update(ctx, NULL, 0);
+    if (!in_len)
+      return;
+  }
+
+  if (in_len >= blocksize)
+  {
+    inblocks = in_len / blocksize;
+    ctx->transform(ctx, in_buf, inblocks);
+    ctx->count = 0;
+    ctx->nblocks_high += (ctx->nblocks + inblocks < inblocks);
+    ctx->nblocks += inblocks;
+    in_len -= inblocks * blocksize;
+    in_buf += inblocks * blocksize;
+  }
+  for (; in_len && ctx->count < blocksize; in_len--)
+    ctx->buf[ctx->count++] = *in_buf++;
+}
+
+/*
+   The routine finally terminates the computation and returns the
+   digest.  The handle is prepared for a new cycle, but adding bytes
+   to the handle will the destroy the returned buffer.  Returns: 32
+   bytes with the message the digest.  */
+byte*
+sha256_final(struct sha256_context *ctx)
+{
+  u32 t, th, msb, lsb;
+  byte *p;
+
+  sha256_update(ctx, NULL, 0); /* flush */;
+
+  t = ctx->nblocks;
+  if (sizeof t == sizeof ctx->nblocks)
+    th = ctx->nblocks_high;
+  else
+    th = 0;
+
+  /* multiply by 64 to make a byte count */
+  lsb = t << 6;
+  msb = (th << 6) | (t >> 26);
+  /* add the count */
+  t = lsb;
+  if ((lsb += ctx->count) < t)
+    msb++;
+  /* multiply by 8 to make a bit count */
+  t = lsb;
+  lsb <<= 3;
+  msb <<= 3;
+  msb |= t >> 29;
+
+  if (ctx->count < 56)
+  { /* enough room */
+    ctx->buf[ctx->count++] = 0x80; /* pad */
+    while (ctx->count < 56)
+      ctx->buf[ctx->count++] = 0;  /* pad */
+  }
+  else
+  { /* need one extra block */
+    ctx->buf[ctx->count++] = 0x80; /* pad character */
+    while (ctx->count < 64)
+      ctx->buf[ctx->count++] = 0;
+    sha256_update(ctx, NULL, 0);  /* flush */;
+    memset (ctx->buf, 0, 56 ); /* fill next block with zeroes */
+  }
+  /* append the 64 bit count */
+  put_u32(ctx->buf + 56, msb);
+  put_u32(ctx->buf + 60, lsb);
+  sha256_transform(ctx, ctx->buf, 1);
+
+  p = ctx->buf;
+
+#define X(a) do { put_u32(p, ctx->h##a); p += 4; } while(0)
+  X(0);
+  X(1);
+  X(2);
+  X(3);
+  X(4);
+  X(5);
+  X(6);
+  X(7);
+#undef X
+
+  return ctx->buf;
+}
+
+
+/*
+ * 	SHA256-HMAC
+ */
+
+static void
+sha256_hash_buffer(byte *outbuf, const byte *buffer, size_t length)
+{
+  struct sha256_context hd_tmp;
+
+  sha256_init(&hd_tmp);
+  sha256_update(&hd_tmp, buffer, length);
+  memcpy(outbuf, sha256_final(&hd_tmp), SHA256_SIZE);
+}
+
+void
+sha256_hmac_init(struct sha256_hmac_context *ctx, const byte *key, size_t keylen)
+{
+  byte keybuf[SHA256_BLOCK_SIZE], buf[SHA256_BLOCK_SIZE];
+
+  /* Hash the key if necessary */
+  if (keylen <= SHA256_BLOCK_SIZE)
+  {
+    memcpy(keybuf, key, keylen);
+    bzero(keybuf + keylen, SHA256_BLOCK_SIZE - keylen);
+  }
+  else
+  {
+    sha256_hash_buffer(keybuf, key, keylen);
+    bzero(keybuf + SHA256_SIZE, SHA256_BLOCK_SIZE - SHA256_SIZE);
+  }
+
+  /* Initialize the inner digest */
+  sha256_init(&ctx->ictx);
+  int i;
+  for (i = 0; i < SHA256_BLOCK_SIZE; i++)
+    buf[i] = keybuf[i] ^ 0x36;
+  sha256_update(&ctx->ictx, buf, SHA256_BLOCK_SIZE);
+
+  /* Initialize the outer digest */
+  sha256_init(&ctx->octx);
+  for (i = 0; i < SHA256_BLOCK_SIZE; i++)
+    buf[i] = keybuf[i] ^ 0x5c;
+  sha256_update(&ctx->octx, buf, SHA256_BLOCK_SIZE);
+}
+
+void sha256_hmac_update(struct sha256_hmac_context *ctx, const byte *buf, size_t buflen)
+{
+  /* Just update the inner digest */
+  sha256_update(&ctx->ictx, buf, buflen);
+}
+
+byte *sha256_hmac_final(struct sha256_hmac_context *ctx)
+{
+  /* Finish the inner digest */
+  byte *isha = sha256_final(&ctx->ictx);
+
+  /* Finish the outer digest */
+  sha256_update(&ctx->octx, isha, SHA256_SIZE);
+  return sha256_final(&ctx->octx);
+}
+
+
+/*
+ * 	SHA224-HMAC
+ */
+
+static void
+sha224_hash_buffer(byte *outbuf, const byte *buffer, size_t length)
+{
+  struct sha224_context hd_tmp;
+
+  sha224_init(&hd_tmp);
+  sha224_update(&hd_tmp, buffer, length);
+  memcpy(outbuf, sha224_final(&hd_tmp), SHA224_SIZE);
+}
+
+void
+sha224_hmac_init(struct sha224_hmac_context *ctx, const byte *key, size_t keylen)
+{
+  byte keybuf[SHA224_BLOCK_SIZE], buf[SHA224_BLOCK_SIZE];
+
+  /* Hash the key if necessary */
+  if (keylen <= SHA224_BLOCK_SIZE)
+  {
+    memcpy(keybuf, key, keylen);
+    bzero(keybuf + keylen, SHA224_BLOCK_SIZE - keylen);
+  }
+  else
+  {
+    sha224_hash_buffer(keybuf, key, keylen);
+    bzero(keybuf + SHA224_SIZE, SHA224_BLOCK_SIZE - SHA224_SIZE);
+  }
+
+  /* Initialize the inner digest */
+  sha224_init(&ctx->ictx);
+  int i;
+  for (i = 0; i < SHA224_BLOCK_SIZE; i++)
+    buf[i] = keybuf[i] ^ 0x36;
+  sha224_update(&ctx->ictx, buf, SHA224_BLOCK_SIZE);
+
+  /* Initialize the outer digest */
+  sha224_init(&ctx->octx);
+  for (i = 0; i < SHA224_BLOCK_SIZE; i++)
+    buf[i] = keybuf[i] ^ 0x5c;
+  sha224_update(&ctx->octx, buf, SHA224_BLOCK_SIZE);
+}
+
+void sha224_hmac_update(struct sha224_hmac_context *ctx, const byte *buf, size_t buflen)
+{
+  /* Just update the inner digest */
+  sha256_update(&ctx->ictx, buf, buflen);
+}
+
+byte *sha224_hmac_final(struct sha224_hmac_context *ctx)
+{
+  /* Finish the inner digest */
+  byte *isha = sha224_final(&ctx->ictx);
+
+  /* Finish the outer digest */
+  sha224_update(&ctx->octx, isha, SHA224_SIZE);
+  return sha224_final(&ctx->octx);
+}