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-rw-r--r--netwerk/srtp/src/crypto/math/math.c802
1 files changed, 802 insertions, 0 deletions
diff --git a/netwerk/srtp/src/crypto/math/math.c b/netwerk/srtp/src/crypto/math/math.c
new file mode 100644
index 000000000..9e3e78ed1
--- /dev/null
+++ b/netwerk/srtp/src/crypto/math/math.c
@@ -0,0 +1,802 @@
+/*
+ * 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"
+
+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;
+}
+
+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;
+}
+
+void
+v16_copy_octet_string(v16_t *x, const uint8_t s[2]) {
+ x->v8[0] = s[0];
+ x->v8[1] = s[1];
+}
+
+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];
+}
+
+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 */
+
+
+static 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 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 */
+
+
+
+
+