Ticket #61: imported libsrtp into third_party directory (backported from srtp branch)

git-svn-id: http://svn.pjsip.org/repos/pjproject/trunk@1730 74dad513-b988-da41-8d7b-12977e46ad98

4 files changed, 2012 insertions, 0 deletions

diff --git a/third_party/srtp/crypto/math/datatypes.c b/third_party/srtp/crypto/math/datatypes.c
new file mode 100644
index 00000000..61bf34fe
--- /dev/null
+++ b/third_party/srtp/crypto/math/datatypes.c
@@ -0,0 +1,600 @@
+/*
+ * datatypes.c
+ *
+ * data types for finite fields and functions for input, output, and
+ * manipulation
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+/*
+ *	
+ * Copyright (c) 2001-2006 Cisco Systems, Inc.
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ *   Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ * 
+ *   Neither the name of the Cisco Systems, Inc. nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "datatypes.h"
+
+int 
+octet_weight[256] = {
+  0, 1, 1, 2, 1, 2, 2, 3,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  5, 6, 6, 7, 6, 7, 7, 8
+};
+
+int
+octet_get_weight(uint8_t octet) {
+  extern int octet_weight[256];
+
+  return octet_weight[octet];
+}  
+
+/*
+ * bit_string is a buffer that is used to hold output strings, e.g.
+ * for printing.
+ */
+
+/* the value MAX_PRINT_STRING_LEN is defined in datatypes.h */
+
+char bit_string[MAX_PRINT_STRING_LEN];
+
+uint8_t
+nibble_to_hex_char(uint8_t nibble) {
+  char buf[16] = {'0', '1', '2', '3', '4', '5', '6', '7',
+		  '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
+  return buf[nibble & 0xF];
+}
+
+char *
+octet_string_hex_string(const void *s, int length) {
+  const uint8_t *str = (const uint8_t *)s;
+  int i;
+  
+  /* double length, since one octet takes two hex characters */
+  length *= 2;
+
+  /* truncate string if it would be too long */
+  if (length > MAX_PRINT_STRING_LEN)
+    length = MAX_PRINT_STRING_LEN-1;
+  
+  for (i=0; i < length; i+=2) {
+    bit_string[i]   = nibble_to_hex_char(*str >> 4);
+    bit_string[i+1] = nibble_to_hex_char(*str++ & 0xF);
+  }
+  bit_string[i] = 0; /* null terminate string */
+  return bit_string;
+}
+
+inline int
+hex_char_to_nibble(uint8_t c) {
+  switch(c) {
+  case ('0'): return 0x0;
+  case ('1'): return 0x1;
+  case ('2'): return 0x2;
+  case ('3'): return 0x3;
+  case ('4'): return 0x4;
+  case ('5'): return 0x5;
+  case ('6'): return 0x6;
+  case ('7'): return 0x7;
+  case ('8'): return 0x8;
+  case ('9'): return 0x9;
+  case ('a'): return 0xa;
+  case ('A'): return 0xa;
+  case ('b'): return 0xb;
+  case ('B'): return 0xb;
+  case ('c'): return 0xc;
+  case ('C'): return 0xc;
+  case ('d'): return 0xd;
+  case ('D'): return 0xd;
+  case ('e'): return 0xe;
+  case ('E'): return 0xe;
+  case ('f'): return 0xf;
+  case ('F'): return 0xf;
+  default: return -1;   /* this flags an error */
+  }
+  /* NOTREACHED */
+  return -1;  /* this keeps compilers from complaining */
+}
+
+int
+is_hex_string(char *s) {
+  while(*s != 0)
+    if (hex_char_to_nibble(*s++) == -1)
+      return 0;
+  return 1;
+}
+
+/*
+ * hex_string_to_octet_string converts a hexadecimal string
+ * of length 2 * len to a raw octet string of length len
+ */
+
+int
+hex_string_to_octet_string(char *raw, char *hex, int len) {
+  uint8_t x;
+  int tmp;
+  int hex_len;
+
+  hex_len = 0;
+  while (hex_len < len) {
+    tmp = hex_char_to_nibble(hex[0]);
+    if (tmp == -1)
+      return hex_len;
+    x = (tmp << 4);
+    hex_len++;
+    tmp = hex_char_to_nibble(hex[1]);
+    if (tmp == -1)
+      return hex_len;
+    x |= (tmp & 0xff);
+    hex_len++;
+    *raw++ = x;
+    hex += 2;
+  }
+  return hex_len;
+}
+
+char *
+v128_hex_string(v128_t *x) {
+  int i, j;
+
+  for (i=j=0; i < 16; i++) {
+    bit_string[j++]  = nibble_to_hex_char(x->v8[i] >> 4);
+    bit_string[j++]  = nibble_to_hex_char(x->v8[i] & 0xF);
+  }
+  
+  bit_string[j] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+v128_bit_string(v128_t *x) {
+  int j, index;
+  uint32_t mask;
+  
+  for (j=index=0; j < 4; j++) {
+    for (mask=0x80000000; mask > 0; mask >>= 1) {
+      if (x->v32[j] & mask)
+	bit_string[index] = '1';
+      else
+	bit_string[index] = '0';
+      ++index;
+    }
+  }
+  bit_string[128] = 0; /* null terminate string */
+
+  return bit_string;
+}
+
+void
+v128_copy_octet_string(v128_t *x, const uint8_t s[16]) {
+#ifdef ALIGNMENT_32BIT_REQUIRED
+  if ((((uint32_t) &s[0]) & 0x3) != 0)
+#endif
+  {
+	  x->v8[0]  = s[0];
+	  x->v8[1]  = s[1];
+	  x->v8[2]  = s[2];
+	  x->v8[3]  = s[3];
+	  x->v8[4]  = s[4];
+	  x->v8[5]  = s[5];
+	  x->v8[6]  = s[6];
+	  x->v8[7]  = s[7];
+	  x->v8[8]  = s[8];
+	  x->v8[9]  = s[9];
+	  x->v8[10] = s[10];
+	  x->v8[11] = s[11];
+	  x->v8[12] = s[12];
+	  x->v8[13] = s[13];
+	  x->v8[14] = s[14];
+	  x->v8[15] = s[15];
+  }
+#ifdef ALIGNMENT_32BIT_REQUIRED
+  else 
+  {
+	  v128_t *v = (v128_t *) &s[0];
+
+	  v128_copy(x,v);
+  }
+#endif
+}
+
+#ifndef DATATYPES_USE_MACROS /* little functions are not macros */
+
+void
+v128_set_to_zero(v128_t *x) {
+  _v128_set_to_zero(x);
+}
+
+void
+v128_copy(v128_t *x, const v128_t *y) {
+  _v128_copy(x, y);
+}
+
+void
+v128_xor(v128_t *z, v128_t *x, v128_t *y) {
+  _v128_xor(z, x, y);
+} 
+
+void
+v128_and(v128_t *z, v128_t *x, v128_t *y) {
+  _v128_and(z, x, y);
+}
+
+void
+v128_or(v128_t *z, v128_t *x, v128_t *y) {
+  _v128_or(z, x, y);
+}
+
+void
+v128_complement(v128_t *x) {
+  _v128_complement(x);
+}
+
+int
+v128_is_eq(const v128_t *x, const v128_t *y) {
+  return _v128_is_eq(x, y);
+}
+
+int
+v128_xor_eq(v128_t *x, const v128_t *y) {
+  return _v128_xor_eq(x, y);
+}
+
+int
+v128_get_bit(const v128_t *x, int i) {
+  return _v128_get_bit(x, i);
+}
+
+void
+v128_set_bit(v128_t *x, int i) {
+  _v128_set_bit(x, i);
+}     
+
+void
+v128_clear_bit(v128_t *x, int i){
+  _v128_clear_bit(x, i);
+}    
+
+void
+v128_set_bit_to(v128_t *x, int i, int y){
+  _v128_set_bit_to(x, i, y);
+}
+
+
+#endif /* DATATYPES_USE_MACROS */
+
+void
+v128_right_shift(v128_t *x, int index) {
+  const int base_index = index >> 5;
+  const int bit_index = index & 31;
+  int i, from;
+  uint32_t b;
+    
+  if (index > 127) {
+    v128_set_to_zero(x);
+    return;
+  }
+
+  if (bit_index == 0) {
+
+    /* copy each word from left size to right side */
+    x->v32[4-1] = x->v32[4-1-base_index];
+    for (i=4-1; i > base_index; i--) 
+      x->v32[i-1] = x->v32[i-1-base_index];
+
+  } else {
+    
+    /* set each word to the "or" of the two bit-shifted words */
+    for (i = 4; i > base_index; i--) {
+      from = i-1 - base_index;
+      b = x->v32[from] << bit_index;
+      if (from > 0)
+        b |= x->v32[from-1] >> (32-bit_index);
+      x->v32[i-1] = b;
+    }
+    
+  }
+
+  /* now wrap up the final portion */
+  for (i=0; i < base_index; i++) 
+    x->v32[i] = 0;
+  
+}
+
+void
+v128_left_shift(v128_t *x, int index) {
+  int i;
+  const int base_index = index >> 5;
+  const int bit_index = index & 31;
+
+  if (index > 127) {
+    v128_set_to_zero(x);
+    return;
+  } 
+  
+  if (bit_index == 0) {
+    for (i=0; i < 4 - base_index; i++)
+      x->v32[i] = x->v32[i+base_index];
+  } else {
+    for (i=0; i < 4 - base_index - 1; i++)
+      x->v32[i] = (x->v32[i+base_index] >> bit_index) ^
+	(x->v32[i+base_index+1] << (32 - bit_index));
+    x->v32[4 - base_index-1] = x->v32[4-1] >> bit_index;
+  }
+
+  /* now wrap up the final portion */
+  for (i = 4 - base_index; i < 4; i++) 
+    x->v32[i] = 0;
+
+}
+
+
+int
+octet_string_is_eq(uint8_t *a, uint8_t *b, int len) {
+  uint8_t *end = b + len;
+  while (b < end)
+    if (*a++ != *b++)
+      return 1;
+  return 0;
+}
+
+void
+octet_string_set_to_zero(uint8_t *s, int len) {
+  uint8_t *end = s + len;
+
+  do {
+    *s = 0;
+  } while (++s < end);
+  
+}
+
+
+/*
+ *  From RFC 1521: The Base64 Alphabet
+ *
+ *   Value Encoding  Value Encoding  Value Encoding  Value Encoding
+ *        0 A            17 R            34 i            51 z
+ *        1 B            18 S            35 j            52 0
+ *        2 C            19 T            36 k            53 1
+ *        3 D            20 U            37 l            54 2
+ *        4 E            21 V            38 m            55 3
+ *        5 F            22 W            39 n            56 4
+ *        6 G            23 X            40 o            57 5
+ *        7 H            24 Y            41 p            58 6
+ *        8 I            25 Z            42 q            59 7
+ *        9 J            26 a            43 r            60 8
+ *       10 K            27 b            44 s            61 9
+ *       11 L            28 c            45 t            62 +
+ *       12 M            29 d            46 u            63 /
+ *       13 N            30 e            47 v
+ *       14 O            31 f            48 w         (pad) =
+ *       15 P            32 g            49 x
+ *       16 Q            33 h            50 y
+ */
+
+int
+base64_char_to_sextet(uint8_t c) {
+  switch(c) {
+  case 'A':
+    return 0;
+  case 'B':
+    return 1;
+  case 'C':
+    return 2;
+  case 'D':
+    return 3;
+  case 'E':
+    return 4;
+  case 'F':
+    return 5;
+  case 'G':
+    return 6;
+  case 'H':
+    return 7;
+  case 'I':
+    return 8;
+  case 'J':
+    return 9;
+  case 'K':
+    return 10;
+  case 'L':
+    return 11;
+  case 'M':
+    return 12;
+  case 'N':
+    return 13;
+  case 'O':
+    return 14;
+  case 'P':
+    return 15;
+  case 'Q':
+    return 16;
+  case 'R':
+    return 17;
+  case 'S':
+    return 18;
+  case 'T':
+    return 19;
+  case 'U':
+    return 20;
+  case 'V':
+    return 21;
+  case 'W':
+    return 22;
+  case 'X':
+    return 23;
+  case 'Y':
+    return 24;
+  case 'Z':
+    return 25;
+  case 'a':
+    return 26;
+  case 'b':
+    return 27;
+  case 'c':
+    return 28;
+  case 'd':
+    return 29;
+  case 'e':
+    return 30;
+  case 'f':
+    return 31;
+  case 'g':
+    return 32;
+  case 'h':
+    return 33;
+  case 'i':
+    return 34;
+  case 'j':
+    return 35;
+  case 'k':
+    return 36;
+  case 'l':
+    return 37;
+  case 'm':
+    return 38;
+  case 'n':
+    return 39;
+  case 'o':
+    return 40;
+  case 'p':
+    return 41;
+  case 'q':
+    return 42;
+  case 'r':
+    return 43;
+  case 's':
+    return 44;
+  case 't':
+    return 45;
+  case 'u':
+    return 46;
+  case 'v':
+    return 47;
+  case 'w':
+    return 48;
+  case 'x':
+    return 49;
+  case 'y':
+    return 50;
+  case 'z':
+    return 51;
+  case '0':
+    return 52;
+  case '1':
+    return 53;
+  case '2':
+    return 54;
+  case '3':
+    return 55;
+  case '4':
+    return 56;
+  case '5':
+    return 57;
+  case '6':
+    return 58;
+  case '7':
+    return 59;
+  case '8':
+    return 60;
+  case '9':
+    return 61;
+  case '+':
+    return 62;
+  case '/':
+    return 63;
+  case '=':
+    return 64;
+  default:
+    break;
+ }
+ return -1;
+}
+
+/*
+ * base64_string_to_octet_string converts a hexadecimal string
+ * of length 2 * len to a raw octet string of length len
+ */
+
+int
+base64_string_to_octet_string(char *raw, char *base64, int len) {
+  uint8_t x;
+  int tmp;
+  int base64_len;
+
+  base64_len = 0;
+  while (base64_len < len) {
+    tmp = base64_char_to_sextet(base64[0]);
+    if (tmp == -1)
+      return base64_len;
+    x = (tmp << 6);
+    base64_len++;
+    tmp = base64_char_to_sextet(base64[1]);
+    if (tmp == -1)
+      return base64_len;
+    x |= (tmp & 0xffff);
+    base64_len++;
+    *raw++ = x;
+    base64 += 2;
+  }
+  return base64_len;
+}
diff --git a/third_party/srtp/crypto/math/gf2_8.c b/third_party/srtp/crypto/math/gf2_8.c
new file mode 100644
index 00000000..8a112ba7
--- /dev/null
+++ b/third_party/srtp/crypto/math/gf2_8.c
@@ -0,0 +1,83 @@
+/*
+ * gf2_8.c
+ *
+ * GF(256) finite field implementation, with the representation used
+ * in the AES cipher.
+ * 
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+
+/*
+ *	
+ * Copyright (c) 2001-2006, Cisco Systems, Inc.
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ *   Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ * 
+ *   Neither the name of the Cisco Systems, Inc. nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+
+#include "datatypes.h"
+#include "gf2_8.h"
+
+/* gf2_8_shift() moved to gf2_8.h as an inline function */
+
+inline gf2_8
+gf2_8_multiply(gf2_8 x, gf2_8 y) {
+  gf2_8 z = 0;
+
+  if (y &   1) z ^= x; x = gf2_8_shift(x);
+  if (y &   2) z ^= x; x = gf2_8_shift(x);
+  if (y &   4) z ^= x; x = gf2_8_shift(x);
+  if (y &   8) z ^= x; x = gf2_8_shift(x);
+  if (y &  16) z ^= x; x = gf2_8_shift(x);
+  if (y &  32) z ^= x; x = gf2_8_shift(x);
+  if (y &  64) z ^= x; x = gf2_8_shift(x);
+  if (y & 128) z ^= x; 
+  
+  return z;
+}
+
+
+/* this should use the euclidean algorithm */
+
+gf2_8
+gf2_8_compute_inverse(gf2_8 x) {
+  unsigned int i;
+
+  if (x == 0) return 0;    /* zero is a special case */
+  for (i=0; i < 256; i++)
+    if (gf2_8_multiply((gf2_8) i, x) == 1)
+      return (gf2_8) i;
+
+    return 0;
+}
+
diff --git a/third_party/srtp/crypto/math/math.c b/third_party/srtp/crypto/math/math.c
new file mode 100644
index 00000000..3e619979
--- /dev/null
+++ b/third_party/srtp/crypto/math/math.c
@@ -0,0 +1,962 @@
+/*
+ * math.c
+ *
+ * crypto math operations and data types
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+/*
+ *	
+ * Copyright (c) 2001-2006 Cisco Systems, Inc.
+ * All rights reserved.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ *   Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * 
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ * 
+ *   Neither the name of the Cisco Systems, Inc. nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "crypto_math.h"
+#include <stdlib.h>           /* malloc() used in bitvector_alloc */
+
+int 
+octet_weight[256] = {
+  0, 1, 1, 2, 1, 2, 2, 3,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  1, 2, 2, 3, 2, 3, 3, 4,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  2, 3, 3, 4, 3, 4, 4, 5,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  3, 4, 4, 5, 4, 5, 5, 6,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  4, 5, 5, 6, 5, 6, 6, 7,
+  5, 6, 6, 7, 6, 7, 7, 8
+};
+
+int
+low_bit[256] = {
+  -1, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  5, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  6, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  5, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  7, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  5, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  6, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  5, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0,
+  4, 0, 1, 0, 2, 0, 1, 0,
+  3, 0, 1, 0, 2, 0, 1, 0
+};
+
+
+int
+high_bit[256] = {
+  -1, 0, 1, 1, 2, 2, 2, 2,
+  3, 3, 3, 3, 3, 3, 3, 3,
+  4, 4, 4, 4, 4, 4, 4, 4,
+  4, 4, 4, 4, 4, 4, 4, 4,
+  5, 5, 5, 5, 5, 5, 5, 5,
+  5, 5, 5, 5, 5, 5, 5, 5,
+  5, 5, 5, 5, 5, 5, 5, 5,
+  5, 5, 5, 5, 5, 5, 5, 5,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  6, 6, 6, 6, 6, 6, 6, 6,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7,
+  7, 7, 7, 7, 7, 7, 7, 7
+};
+
+int
+octet_get_weight(uint8_t octet) {
+  extern int octet_weight[256];
+
+  return octet_weight[octet];
+}  
+
+unsigned char
+v32_weight(v32_t a) {
+  unsigned int wt = 0;
+  
+  wt += octet_weight[a.v8[0]];  /* note: endian-ness makes no difference */
+  wt += octet_weight[a.v8[1]];
+  wt += octet_weight[a.v8[2]];
+  wt += octet_weight[a.v8[3]];
+  
+  return wt;
+}
+
+inline unsigned char
+v32_distance(v32_t x, v32_t y) {
+  x.value ^= y.value;
+  return v32_weight(x);
+}
+
+unsigned int
+v32_dot_product(v32_t a, v32_t b) {
+  a.value &= b.value;
+  return v32_weight(a) & 1;
+}
+
+/*
+ * _bit_string returns a NULL-terminated character string suitable for
+ * printing
+ */
+
+#define MAX_STRING_LENGTH 1024
+
+char bit_string[MAX_STRING_LENGTH];
+
+char *
+octet_bit_string(uint8_t x) {
+  int mask, index;
+
+  for (mask = 1, index = 0; mask < 256; mask <<= 1)
+    if ((x & mask) == 0)
+      bit_string[index++] = '0';
+    else
+      bit_string[index++] = '1';
+
+  bit_string[index++] = 0;  /* NULL terminate string */
+
+  return bit_string;
+}
+
+char *
+v16_bit_string(v16_t x) {
+  int i, mask, index;
+
+  for (i = index = 0; i < 2; i++) {
+    for (mask = 1; mask < 256; mask <<= 1)
+      if ((x.v8[i] & mask) == 0)
+	bit_string[index++] = '0';
+      else
+	bit_string[index++] = '1';
+  }
+  bit_string[index++] = 0;  /* NULL terminate string */
+  return bit_string;
+}
+
+char *
+v32_bit_string(v32_t x) {
+  int i, mask, index;
+
+  for (i = index = 0; i < 4; i++) {
+    for (mask = 128; mask > 0; mask >>= 1)
+      if ((x.v8[i] & mask) == 0)
+	bit_string[index++] = '0';
+      else
+	bit_string[index++] = '1';
+  }
+  bit_string[index++] = 0;  /* NULL terminate string */
+  return bit_string;
+}
+
+char *
+v64_bit_string(const v64_t *x) {
+  int i, mask, index;
+
+  for (i = index = 0; i < 8; i++) {
+    for (mask = 1; mask < 256; mask <<= 1)
+      if ((x->v8[i] & mask) == 0)
+	bit_string[index++] = '0';
+      else
+	bit_string[index++] = '1';
+  }
+  bit_string[index++] = 0;  /* NULL terminate string */
+  return bit_string;
+}
+
+char *
+v128_bit_string(v128_t *x) {
+  int j, index;
+  uint32_t mask;
+  
+  for (j=index=0; j < 4; j++) {
+    for (mask=0x80000000; mask > 0; mask >>= 1) {
+      if (x->v32[j] & mask)
+	bit_string[index] = '1';
+      else
+	bit_string[index] = '0';
+      ++index;
+    }
+  }
+  bit_string[128] = 0; /* null terminate string */
+
+  return bit_string;
+}
+
+uint8_t
+nibble_to_hex_char(uint8_t nibble) {
+  char buf[16] = {'0', '1', '2', '3', '4', '5', '6', '7',
+		  '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
+  return buf[nibble & 0xF];
+}
+
+char *
+octet_hex_string(uint8_t x) {
+
+  bit_string[0]  = nibble_to_hex_char(x >> 4);
+  bit_string[1]  = nibble_to_hex_char(x & 0xF);
+  
+  bit_string[2] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+octet_string_hex_string(const void *str, int length) {
+  const uint8_t *s = str;
+  int i;
+  
+  /* double length, since one octet takes two hex characters */
+  length *= 2;
+
+  /* truncate string if it would be too long */
+  if (length > MAX_STRING_LENGTH)
+    length = MAX_STRING_LENGTH-1;
+  
+  for (i=0; i < length; i+=2) {
+    bit_string[i]   = nibble_to_hex_char(*s >> 4);
+    bit_string[i+1] = nibble_to_hex_char(*s++ & 0xF);
+  }
+  bit_string[i] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+v16_hex_string(v16_t x) {
+  int i, j;
+
+  for (i=j=0; i < 2; i++) {
+    bit_string[j++]  = nibble_to_hex_char(x.v8[i] >> 4);
+    bit_string[j++]  = nibble_to_hex_char(x.v8[i] & 0xF);
+  }
+  
+  bit_string[j] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+v32_hex_string(v32_t x) {
+  int i, j;
+
+  for (i=j=0; i < 4; i++) {
+    bit_string[j++]  = nibble_to_hex_char(x.v8[i] >> 4);
+    bit_string[j++]  = nibble_to_hex_char(x.v8[i] & 0xF);
+  }
+  
+  bit_string[j] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+v64_hex_string(const v64_t *x) {
+  int i, j;
+
+  for (i=j=0; i < 8; i++) {
+    bit_string[j++]  = nibble_to_hex_char(x->v8[i] >> 4);
+    bit_string[j++]  = nibble_to_hex_char(x->v8[i] & 0xF);
+  }
+  
+  bit_string[j] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+v128_hex_string(v128_t *x) {
+  int i, j;
+
+  for (i=j=0; i < 16; i++) {
+    bit_string[j++]  = nibble_to_hex_char(x->v8[i] >> 4);
+    bit_string[j++]  = nibble_to_hex_char(x->v8[i] & 0xF);
+  }
+  
+  bit_string[j] = 0; /* null terminate string */
+  return bit_string;
+}
+
+char *
+char_to_hex_string(char *x, int num_char) {
+  int i, j;
+
+  if (num_char >= 16)
+    num_char = 16;
+  for (i=j=0; i < num_char; i++) {
+    bit_string[j++]  = nibble_to_hex_char(x[i] >> 4);
+    bit_string[j++]  = nibble_to_hex_char(x[i] & 0xF);
+  }
+  
+  bit_string[j] = 0; /* null terminate string */
+  return bit_string;
+}
+
+int
+hex_char_to_nibble(uint8_t c) {
+  switch(c) {
+  case ('0'): return 0x0;
+  case ('1'): return 0x1;
+  case ('2'): return 0x2;
+  case ('3'): return 0x3;
+  case ('4'): return 0x4;
+  case ('5'): return 0x5;
+  case ('6'): return 0x6;
+  case ('7'): return 0x7;
+  case ('8'): return 0x8;
+  case ('9'): return 0x9;
+  case ('a'): return 0xa;
+  case ('A'): return 0xa;
+  case ('b'): return 0xb;
+  case ('B'): return 0xb;
+  case ('c'): return 0xc;
+  case ('C'): return 0xc;
+  case ('d'): return 0xd;
+  case ('D'): return 0xd;
+  case ('e'): return 0xe;
+  case ('E'): return 0xe;
+  case ('f'): return 0xf;
+  case ('F'): return 0xf;
+  default: return -1;   /* this flags an error */
+  }
+  /* NOTREACHED */
+  return -1;  /* this keeps compilers from complaining */
+}
+
+int
+is_hex_string(char *s) {
+  while(*s != 0)
+    if (hex_char_to_nibble(*s++) == -1)
+      return 0;
+  return 1;
+}
+
+uint8_t
+hex_string_to_octet(char *s) {
+  uint8_t x;
+
+  x = (hex_char_to_nibble(s[0]) << 4)
+    | hex_char_to_nibble(s[1] & 0xFF);
+  
+  return x;
+}
+
+/*
+ * hex_string_to_octet_string converts a hexadecimal string
+ * of length 2 * len to a raw octet string of length len
+ */
+
+int
+hex_string_to_octet_string(char *raw, char *hex, int len) {
+  uint8_t x;
+  int tmp;
+  int hex_len;
+
+  hex_len = 0;
+  while (hex_len < len) {
+    tmp = hex_char_to_nibble(hex[0]);
+    if (tmp == -1)
+      return hex_len;
+    x = (tmp << 4);
+    hex_len++;
+    tmp = hex_char_to_nibble(hex[1]);
+    if (tmp == -1)
+      return hex_len;
+    x |= (tmp & 0xff);
+    hex_len++;
+    *raw++ = x;
+    hex += 2;
+  }
+  return hex_len;
+}
+
+v16_t
+hex_string_to_v16(char *s) {
+  v16_t x;
+  int i, j;
+
+  for (i=j=0; i < 4; i += 2, j++) {
+    x.v8[j] = (hex_char_to_nibble(s[i]) << 4)
+      | hex_char_to_nibble(s[i+1] & 0xFF);
+  }
+  return x;
+}
+
+v32_t
+hex_string_to_v32(char *s) {
+  v32_t x;
+  int i, j;
+
+  for (i=j=0; i < 8; i += 2, j++) {
+    x.v8[j] = (hex_char_to_nibble(s[i]) << 4)
+      | hex_char_to_nibble(s[i+1] & 0xFF);
+  }
+  return x;
+}
+
+v64_t
+hex_string_to_v64(char *s) {
+  v64_t x;
+  int i, j;
+
+  for (i=j=0; i < 16; i += 2, j++) {
+    x.v8[j] = (hex_char_to_nibble(s[i]) << 4)
+      | hex_char_to_nibble(s[i+1] & 0xFF);
+  }
+  return x;
+}
+
+v128_t
+hex_string_to_v128(char *s) {
+  v128_t x;
+  int i, j;
+
+  for (i=j=0; i < 32; i += 2, j++) {
+    x.v8[j] = (hex_char_to_nibble(s[i]) << 4)
+      | hex_char_to_nibble(s[i+1] & 0xFF);
+  }
+  return x;
+}
+
+
+
+/* 
+ * the matrix A[] is stored in column format, i.e., A[i] is the ith
+ * column of the matrix 
+ */
+
+uint8_t 
+A_times_x_plus_b(uint8_t A[8], uint8_t x, uint8_t b) {
+  int index = 0;
+  unsigned mask;
+  
+  for (mask=1; mask < 256; mask *= 2) {
+    if (x & mask)
+      b^= A[index];
+    ++index;
+  }
+
+  return b;
+}
+
+inline void
+v16_copy_octet_string(v16_t *x, const uint8_t s[2]) {
+  x->v8[0]  = s[0];
+  x->v8[1]  = s[1];
+}
+
+inline void
+v32_copy_octet_string(v32_t *x, const uint8_t s[4]) {
+  x->v8[0]  = s[0];
+  x->v8[1]  = s[1];
+  x->v8[2]  = s[2];
+  x->v8[3]  = s[3];
+}
+
+inline void
+v64_copy_octet_string(v64_t *x, const uint8_t s[8]) {
+  x->v8[0]  = s[0];
+  x->v8[1]  = s[1];
+  x->v8[2]  = s[2];
+  x->v8[3]  = s[3];
+  x->v8[4]  = s[4];
+  x->v8[5]  = s[5];
+  x->v8[6]  = s[6];
+  x->v8[7]  = s[7];
+}
+
+void
+v128_copy_octet_string(v128_t *x, const uint8_t s[16]) {
+  x->v8[0]  = s[0];
+  x->v8[1]  = s[1];
+  x->v8[2]  = s[2];
+  x->v8[3]  = s[3];
+  x->v8[4]  = s[4];
+  x->v8[5]  = s[5];
+  x->v8[6]  = s[6];
+  x->v8[7]  = s[7];
+  x->v8[8]  = s[8];
+  x->v8[9]  = s[9];
+  x->v8[10] = s[10];
+  x->v8[11] = s[11];
+  x->v8[12] = s[12];
+  x->v8[13] = s[13];
+  x->v8[14] = s[14];
+  x->v8[15] = s[15];
+
+}
+
+#ifndef DATATYPES_USE_MACROS /* little functions are not macros */
+
+void
+v128_set_to_zero(v128_t *x) {
+  _v128_set_to_zero(x);
+}
+
+void
+v128_copy(v128_t *x, const v128_t *y) {
+  _v128_copy(x, y);
+}
+
+void
+v128_xor(v128_t *z, v128_t *x, v128_t *y) {
+  _v128_xor(z, x, y);
+} 
+
+void
+v128_and(v128_t *z, v128_t *x, v128_t *y) {
+  _v128_and(z, x, y);
+}
+
+void
+v128_or(v128_t *z, v128_t *x, v128_t *y) {
+  _v128_or(z, x, y);
+}
+
+void
+v128_complement(v128_t *x) {
+  _v128_complement(x);
+}
+
+int
+v128_is_eq(const v128_t *x, const v128_t *y) {
+  return _v128_is_eq(x, y);
+}
+
+int
+v128_get_bit(const v128_t *x, int i) {
+  return _v128_get_bit(x, i);
+}
+
+void
+v128_set_bit(v128_t *x, int i) {
+  _v128_set_bit(x, i);
+}     
+
+void
+v128_clear_bit(v128_t *x, int i){
+  _v128_clear_bit(x, i);
+}    
+
+void
+v128_set_bit_to(v128_t *x, int i, int y){
+  _v128_set_bit_to(x, i, y);
+}
+
+
+#endif /* DATATYPES_USE_MACROS */
+
+
+inline void
+v128_left_shift2(v128_t *x, int num_bits) {
+  int i;
+  int word_shift = num_bits >> 5;
+  int bit_shift  = num_bits & 31;
+
+  for (i=0; i < (4-word_shift); i++) {
+    x->v32[i] = x->v32[i+word_shift] << bit_shift;
+  }
+  
+  for (   ; i < word_shift; i++) {
+    x->v32[i] = 0;
+  }
+  
+}
+
+void
+v128_right_shift(v128_t *x, int index) {
+  const int base_index = index >> 5;
+  const int bit_index = index & 31;
+  int i, from;
+  uint32_t b;
+    
+  if (index > 127) {
+    v128_set_to_zero(x);
+    return;
+  }
+
+  if (bit_index == 0) {
+
+    /* copy each word from left size to right side */
+    x->v32[4-1] = x->v32[4-1-base_index];
+    for (i=4-1; i > base_index; i--) 
+      x->v32[i-1] = x->v32[i-1-base_index];
+
+  } else {
+    
+    /* set each word to the "or" of the two bit-shifted words */
+    for (i = 4; i > base_index; i--) {
+      from = i-1 - base_index;
+      b = x->v32[from] << bit_index;
+      if (from > 0)
+        b |= x->v32[from-1] >> (32-bit_index);
+      x->v32[i-1] = b;
+    }
+    
+  }
+
+  /* now wrap up the final portion */
+  for (i=0; i < base_index; i++) 
+    x->v32[i] = 0;
+  
+}
+
+void
+v128_left_shift(v128_t *x, int index) {
+  int i;
+  const int base_index = index >> 5;
+  const int bit_index = index & 31;
+
+  if (index > 127) {
+    v128_set_to_zero(x);
+    return;
+  } 
+  
+  if (bit_index == 0) {
+    for (i=0; i < 4 - base_index; i++)
+      x->v32[i] = x->v32[i+base_index];
+  } else {
+    for (i=0; i < 4 - base_index - 1; i++)
+      x->v32[i] = (x->v32[i+base_index] << bit_index) ^
+	(x->v32[i+base_index+1] >> (32 - bit_index));
+    x->v32[4 - base_index-1] = x->v32[4-1] << bit_index;
+  }
+
+  /* now wrap up the final portion */
+  for (i = 4 - base_index; i < 4; i++) 
+    x->v32[i] = 0;
+
+}
+
+
+#if 0
+void
+v128_add(v128_t *z, v128_t *x, v128_t *y) {
+  /* integer addition modulo 2^128    */
+
+#ifdef WORDS_BIGENDIAN
+  uint64_t tmp;
+    
+  tmp = x->v32[3] + y->v32[3];
+  z->v32[3] = (uint32_t) tmp;
+  
+  tmp =  x->v32[2] + y->v32[2] + (tmp >> 32);
+  z->v32[2] = (uint32_t) tmp;
+
+  tmp =  x->v32[1] + y->v32[1] + (tmp >> 32);
+  z->v32[1] = (uint32_t) tmp;
+  
+  tmp =  x->v32[0] + y->v32[0] + (tmp >> 32);
+  z->v32[0] = (uint32_t) tmp;
+
+#else /* assume little endian architecture */
+  uint64_t tmp;
+  
+  tmp = htonl(x->v32[3]) + htonl(y->v32[3]);
+  z->v32[3] = ntohl((uint32_t) tmp);
+  
+  tmp =  htonl(x->v32[2]) + htonl(y->v32[2]) + htonl(tmp >> 32);
+  z->v32[2] = ntohl((uint32_t) tmp);
+
+  tmp =  htonl(x->v32[1]) + htonl(y->v32[1]) + htonl(tmp >> 32);
+  z->v32[1] = ntohl((uint32_t) tmp);
+  
+  tmp =  htonl(x->v32[0]) + htonl(y->v32[0]) + htonl(tmp >> 32);
+  z->v32[0] = ntohl((uint32_t) tmp);
+
+#endif /* WORDS_BIGENDIAN */
+  
+}
+#endif
+
+int
+octet_string_is_eq(uint8_t *a, uint8_t *b, int len) {
+  uint8_t *end = b + len;
+  while (b < end)
+    if (*a++ != *b++)
+      return 1;
+  return 0;
+}
+
+void
+octet_string_set_to_zero(uint8_t *s, int len) {
+  uint8_t *end = s + len;
+
+  do {
+    *s = 0;
+  } while (++s < end);
+  
+}
+
+/* functions manipulating bit_vector_t */
+
+#define BITVECTOR_MAX_WORDS 5
+
+int
+bitvector_alloc(bitvector_t *v, unsigned long length) {
+  unsigned long l = (length + bytes_per_word - 1) / bytes_per_word;
+  int i;
+
+  /* allocate memory, then set parameters */
+  if (l > BITVECTOR_MAX_WORDS)
+    return -1;
+  else
+    l = BITVECTOR_MAX_WORDS;
+  v->word   = malloc(l);
+  if (v->word == NULL)
+    return -1;
+  v->length = length;
+
+  /* initialize bitvector to zero */
+  for (i=0; i < (length >> 5); i++) {
+    v->word = 0;
+  }
+
+  return 0;
+}
+
+void
+bitvector_set_bit(bitvector_t *v, int bit_index) {
+
+  v->word[(bit_index >> 5)] |= (1 << (bit_index & 31));
+  
+}
+
+int
+bitvector_get_bit(const bitvector_t *v, int bit_index) {
+
+  return ((v->word[(bit_index >> 5)]) >> (bit_index & 31)) & 1;
+  
+}
+
+#include <stdio.h>
+
+int
+bitvector_print_hex(const bitvector_t *v, FILE *stream) {
+  int i;
+  int m = v->length >> 5;
+  int n = v->length & 31;
+  char string[9];
+  uint32_t tmp;
+
+  /* if length isn't a multiple of four, we can't hex_print */
+  if (n & 3)
+    return -1;
+  
+  /* if the length is zero, do nothing */
+  if (v->length == 0)
+    return 0;
+
+  /*
+   * loop over words from most significant to least significant - 
+   */
+  
+  for (i=m; i > 0; i++) {
+    char *str = string + 7;
+    tmp = v->word[i];
+    
+    /* null terminate string */
+    string[8] = 0;   
+
+    /* loop over nibbles */
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);  tmp >>= 4; 
+    *str-- = nibble_to_hex_char(tmp & 0xf);   
+
+    /* now print stream */
+    fprintf(stream, string);
+  }
+  
+  return 0;
+
+}
+
+
+int
+hex_string_length(char *s) {
+  int count = 0;
+  
+  /* ignore leading zeros */
+  while ((*s != 0) && *s == '0')
+    s++;
+
+  /* count remaining characters */
+  while (*s != 0) {
+    if (hex_char_to_nibble(*s++) == -1)
+      return -1;
+    count++;
+  }
+
+  return count;
+}
+
+int
+bitvector_set_from_hex(bitvector_t *v, char *string) {
+  int num_hex_chars, m, n, i, j;
+  uint32_t tmp;
+  
+  num_hex_chars = hex_string_length(string);
+  if (num_hex_chars == -1)
+    return -1;
+
+  /* set length */
+  v->length = num_hex_chars * 4;
+  /* 
+   * at this point, we should subtract away a bit if the high
+   * bit of the first character is zero, but we ignore that 
+   * for now and assume that we're four-bit aligned - DAM
+   */
+
+  
+  m = num_hex_chars / 8;   /* number of words                */
+  n = num_hex_chars % 8;   /* number of nibbles in last word */
+
+  /* if the length is greater than the bitvector, return an error */
+  if (m > BITVECTOR_MAX_WORDS)
+    return -1;
+
+  /* 
+   * loop over words from most significant - first word is a special
+   * case 
+   */
+  
+  if (n) {
+    tmp = 0;
+    for (i=0; i < n; i++) {
+      tmp = hex_char_to_nibble(*string++); 
+      tmp <<= 4;  
+    }
+    v->word[m] = tmp;
+  }
+
+  /* now loop over the rest of the words */
+  for (i=m-1; i >= 0; i--) {
+     tmp = 0;
+     for (j=0; j < 8; j++) {
+       tmp = hex_char_to_nibble(*string++); 
+       tmp <<= 4;  
+     }
+     v->word[i] = tmp;
+  }
+
+  return 0;
+}
+
+
+/* functions below not yet tested! */
+
+int
+v32_low_bit(v32_t *w) {
+  int value;
+
+  value = low_bit[w->v8[0]];
+  if (value != -1)
+    return value;
+  value = low_bit[w->v8[1]];
+  if (value != -1)
+    return value + 8;
+  value = low_bit[w->v8[2]];
+  if (value != -1)
+    return value + 16;
+  value = low_bit[w->v8[3]];
+  if (value == -1)
+    return -1;
+  return value + 24;
+}
+
+/* high_bit not done yet */
+
+
+
+
+
diff --git a/third_party/srtp/crypto/math/stat.c b/third_party/srtp/crypto/math/stat.c
new file mode 100644
index 00000000..5e46c209
--- /dev/null
+++ b/third_party/srtp/crypto/math/stat.c
@@ -0,0 +1,367 @@
+/*
+ * stats.c
+ *
+ * statistical tests for randomness (FIPS 140-2, Section 4.9)
+ * 
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+
+#include "stat.h"
+
+debug_module_t mod_stat = {
+  0,                 /* debugging is off by default */
+  (char *)"stat test"        /* printable module name       */
+};
+
+/*
+ * each test assumes that 20,000 bits (2500 octets) of data is
+ * provided as input
+ */
+
+#define STAT_TEST_DATA_LEN 2500
+
+err_status_t
+stat_test_monobit(uint8_t *data) {
+  uint8_t *data_end = data + STAT_TEST_DATA_LEN;
+  uint16_t ones_count;
+
+  ones_count = 0;
+  while (data < data_end) {
+    ones_count += octet_get_weight(*data);
+    data++;
+  }
+
+  debug_print(mod_stat, "bit count: %d", ones_count);
+  
+  if ((ones_count < 9725) || (ones_count > 10275))
+    return err_status_algo_fail;
+
+  return err_status_ok;
+}
+
+err_status_t
+stat_test_poker(uint8_t *data) {
+  int i;
+  uint8_t *data_end = data + STAT_TEST_DATA_LEN;
+  double poker;
+  uint16_t f[16] = {
+    0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0
+  };
+  
+  while (data < data_end) {
+    f[*data & 0x0f]++;    /* increment freq. count for low nibble  */
+    f[(*data) >> 4]++;    /* increment freq. count for high nibble */
+    data++;
+  }
+
+  poker = 0.0;
+  for (i=0; i < 16; i++) 
+    poker += (double) f[i] * f[i];
+
+  poker *= (16.0 / 5000.0);
+  poker -= 5000.0;
+
+  debug_print(mod_stat, "poker test: %f\n", poker);
+    
+  if ((poker < 2.16) || (poker > 46.17))
+    return err_status_algo_fail;
+  
+  return err_status_ok;
+}
+
+
+/*
+ * runs[i] holds the number of runs of size (i-1)
+ */
+
+err_status_t
+stat_test_runs(uint8_t *data) {
+  uint8_t *data_end = data + STAT_TEST_DATA_LEN;
+  uint16_t runs[6] = { 0, 0, 0, 0, 0, 0 }; 
+  uint16_t gaps[6] = { 0, 0, 0, 0, 0, 0 };
+  uint16_t lo_value[6] = { 2315, 1114, 527, 240, 103, 103 };
+  uint16_t hi_value[6] = { 2685, 1386, 723, 384, 209, 209 };
+  int state = 0;
+  uint16_t mask;
+  int i;
+  
+  /*
+   * the state variable holds the number of bits in the
+   * current run (or gap, if negative)
+   */
+  
+  while (data < data_end) {
+
+    /* loop over the bits of this byte */
+    for (mask = 1; mask < 256; mask <<= 1) {
+      if (*data & mask) {
+
+ 	/* next bit is a one  */
+	if (state > 0) {
+
+	  /* prefix is a run, so increment the run-count  */
+	  state++;                          
+
+	  /* check for long runs */ 
+	  if (state > 25) {
+		debug_print(mod_stat, ">25 runs: %d", state);
+		return err_status_algo_fail;
+	  }
+
+	} else if (state < 0) {
+
+	  /* prefix is a gap  */
+	  if (state < -25) {
+		debug_print(mod_stat, ">25 gaps: %d", state);
+	    return err_status_algo_fail;    /* long-runs test failed   */
+	  }
+	  if (state < -6) {
+	    state = -6;                     /* group together gaps > 5 */
+	  }
+	  gaps[-1-state]++;                 /* increment gap count      */
+          state = 1;                        /* set state at one set bit */
+	} else {
+
+	  /* state is zero; this happens only at initialization        */
+	  state = 1;            
+	}
+      } else {
+
+	/* next bit is a zero  */
+	if (state > 0) {
+
+	  /* prefix is a run */
+	  if (state > 25) {
+		debug_print(mod_stat, ">25 runs (2): %d", state);
+	    return err_status_algo_fail;    /* long-runs test failed   */
+	  }
+	  if (state > 6) {
+	    state = 6;                      /* group together runs > 5 */
+	  }
+	  runs[state-1]++;                  /* increment run count       */
+          state = -1;                       /* set state at one zero bit */
+	} else if (state < 0) {
+
+	  /* prefix is a gap, so increment gap-count (decrement state) */
+	  state--;
+
+	  /* check for long gaps */ 
+	  if (state < -25) {
+		debug_print(mod_stat, ">25 gaps (2): %d", state);
+	    return err_status_algo_fail;
+	  }
+
+	} else {
+
+	  /* state is zero; this happens only at initialization        */
+	  state = -1;
+	}
+      }
+    }
+
+    /* move along to next octet */
+    data++;
+  }
+
+  if (mod_stat.on) {
+    debug_print(mod_stat, "runs test", NULL);
+    for (i=0; i < 6; i++)
+      debug_print(mod_stat, "  runs[]: %d", runs[i]);
+    for (i=0; i < 6; i++)
+      debug_print(mod_stat, "  gaps[]: %d", gaps[i]);
+  }
+
+  /* check run and gap counts against the fixed limits */
+  for (i=0; i < 6; i++) 
+    if (   (runs[i] < lo_value[i] ) || (runs[i] > hi_value[i])
+	|| (gaps[i] < lo_value[i] ) || (gaps[i] > hi_value[i]))
+      return err_status_algo_fail;
+
+  
+  return err_status_ok;
+}
+
+
+/*
+ * the function stat_test_rand_source applys the FIPS-140-2 statistical
+ * tests to the random source defined by rs
+ *
+ */
+
+#define RAND_SRC_BUF_OCTETS 50 /* this value MUST divide 2500! */ 
+
+err_status_t
+stat_test_rand_source(rand_source_func_t get_rand_bytes) {
+  int i;
+  double poker;
+  uint8_t *data, *data_end;
+  uint16_t f[16] = {
+    0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0
+  };
+  uint8_t buffer[RAND_SRC_BUF_OCTETS];
+  err_status_t status;
+  int ones_count = 0;
+  uint16_t runs[6] = { 0, 0, 0, 0, 0, 0 }; 
+  uint16_t gaps[6] = { 0, 0, 0, 0, 0, 0 };
+  uint16_t lo_value[6] = { 2315, 1114, 527, 240, 103, 103 };
+  uint16_t hi_value[6] = { 2685, 1386, 723, 384, 209, 209 };
+  int state = 0;
+  uint16_t mask;
+  
+  /* counters for monobit, poker, and runs tests are initialized above */
+
+  /* main loop: fill buffer, update counters for stat tests */
+  for (i=0; i < 2500; i+=RAND_SRC_BUF_OCTETS) {
+    
+    /* fill data buffer */
+    status = get_rand_bytes(buffer, RAND_SRC_BUF_OCTETS);
+    if (status) {
+	  debug_print(mod_stat, "couldn't get rand bytes: %d",status);
+      return status;
+	}
+
+#if 0
+    debug_print(mod_stat, "%s", 
+		octet_string_hex_string(buffer, RAND_SRC_BUF_OCTETS));
+#endif
+  
+    data = buffer;
+    data_end = data + RAND_SRC_BUF_OCTETS;
+    while (data < data_end) {
+
+      /* update monobit test counter */
+      ones_count += octet_get_weight(*data);
+
+      /* update poker test counters */
+      f[*data & 0x0f]++;    /* increment freq. count for low nibble  */
+      f[(*data) >> 4]++;    /* increment freq. count for high nibble */
+
+      /* update runs test counters */
+      /* loop over the bits of this byte */
+      for (mask = 1; mask < 256; mask <<= 1) {
+	if (*data & mask) {
+	  
+	  /* next bit is a one  */
+	  if (state > 0) {
+	    
+	    /* prefix is a run, so increment the run-count  */
+	    state++;                          
+	    
+	    /* check for long runs */ 
+	    if (state > 25) {
+		  debug_print(mod_stat, ">25 runs (3): %d", state);
+	      return err_status_algo_fail;
+		}
+	    
+	  } else if (state < 0) {
+	    
+	    /* prefix is a gap  */
+	    if (state < -25) {
+		  debug_print(mod_stat, ">25 gaps (3): %d", state);
+	      return err_status_algo_fail;    /* long-runs test failed   */
+	    }
+	    if (state < -6) {
+	      state = -6;                     /* group together gaps > 5 */
+	    }
+	    gaps[-1-state]++;                 /* increment gap count      */
+	    state = 1;                        /* set state at one set bit */
+	  } else {
+	    
+	    /* state is zero; this happens only at initialization        */
+	    state = 1;            
+	  }
+	} else {
+	  
+	  /* next bit is a zero  */
+	  if (state > 0) {
+	    
+	    /* prefix is a run */
+	    if (state > 25) {
+		  debug_print(mod_stat, ">25 runs (4): %d", state);
+	      return err_status_algo_fail;    /* long-runs test failed   */
+	    }
+	    if (state > 6) {
+	      state = 6;                      /* group together runs > 5 */
+	    }
+	    runs[state-1]++;                  /* increment run count       */
+	    state = -1;                       /* set state at one zero bit */
+	  } else if (state < 0) {
+	    
+	    /* prefix is a gap, so increment gap-count (decrement state) */
+	    state--;
+	    
+	    /* check for long gaps */ 
+	    if (state < -25) {
+		  debug_print(mod_stat, ">25 gaps (4): %d", state);
+	      return err_status_algo_fail;
+		}
+	    
+	  } else {
+	    
+	    /* state is zero; this happens only at initialization        */
+	    state = -1;
+	  }
+	}
+      }
+      
+      /* advance data pointer */
+      data++;
+    }
+  }
+
+  /* check to see if test data is within bounds */
+
+  /* check monobit test data */
+
+  debug_print(mod_stat, "stat: bit count: %d", ones_count);
+  
+  if ((ones_count < 9725) || (ones_count > 10275)) {
+    debug_print(mod_stat, "stat: failed monobit test %d", ones_count);
+    return err_status_algo_fail;
+  }
+  
+  /* check poker test data */
+  poker = 0.0;
+  for (i=0; i < 16; i++) 
+    poker += (double) f[i] * f[i];
+
+  poker *= (16.0 / 5000.0);
+  poker -= 5000.0;
+
+  debug_print(mod_stat, "stat: poker test: %f", poker);
+    
+  if ((poker < 2.16) || (poker > 46.17)) {
+    debug_print(mod_stat, "stat: failed poker test", NULL);
+    return err_status_algo_fail;
+  }
+
+  /* check run and gap counts against the fixed limits */
+  for (i=0; i < 6; i++) 
+    if ((runs[i] < lo_value[i] ) || (runs[i] > hi_value[i])
+	 || (gaps[i] < lo_value[i] ) || (gaps[i] > hi_value[i])) {
+      debug_print(mod_stat, "stat: failed run/gap test", NULL);
+      return err_status_algo_fail; 
+    }
+
+  debug_print(mod_stat, "passed random stat test", NULL);
+  return err_status_ok;
+}
+
+err_status_t
+stat_test_rand_source_with_repetition(rand_source_func_t source, unsigned num_trials) {
+  unsigned int i;
+  err_status_t err = err_status_algo_fail;
+
+  for (i=0; i < num_trials; i++) {
+    err = stat_test_rand_source(source);
+    if (err == err_status_ok) {
+      return err_status_ok;  
+    }
+    debug_print(mod_stat, "failed stat test (try number %d)\n", i);
+  }
+  
+  return err;
+}