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-rw-r--r--srtp/crypto/rng/prng.c180
1 files changed, 0 insertions, 180 deletions
diff --git a/srtp/crypto/rng/prng.c b/srtp/crypto/rng/prng.c
deleted file mode 100644
index 69350a4..0000000
--- a/srtp/crypto/rng/prng.c
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@@ -1,180 +0,0 @@
-/*
- * prng.c
- *
- * pseudorandom source
- *
- * 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 "prng.h"
-
-/* single, global prng structure */
-
-x917_prng_t x917_prng;
-
-err_status_t
-x917_prng_init(rand_source_func_t random_source) {
- v128_t tmp_key;
- err_status_t status;
-
- /* initialize output count to zero */
- x917_prng.octet_count = 0;
-
- /* set random source */
- x917_prng.rand = random_source;
-
- /* initialize secret key from random source */
- status = random_source((uint8_t *)&tmp_key, 16);
- if (status)
- return status;
-
- /* expand aes key */
- aes_expand_encryption_key(&tmp_key, x917_prng.key);
-
- /* initialize prng state from random source */
- status = x917_prng.rand((uint8_t *)&x917_prng.state, 16);
- if (status)
- return status;
-
- return err_status_ok;
-}
-
-err_status_t
-x917_prng_get_octet_string(uint8_t *dest, uint32_t len) {
- uint32_t t;
- v128_t buffer;
- uint32_t i, tail_len;
- err_status_t status;
-
- /*
- * if we need to re-initialize the prng, do so now
- *
- * avoid overflows by subtracting instead of adding
- */
- if (x917_prng.octet_count > MAX_PRNG_OUT_LEN - len) {
- status = x917_prng_init(x917_prng.rand);
- if (status)
- return status;
- }
- x917_prng.octet_count += len;
-
- /* find out the time */
- t = (uint32_t)time(NULL);
-
- /* loop until we have output enough data */
- for (i=0; i < len/16; i++) {
-
- /* exor time into state */
- x917_prng.state.v32[0] ^= t;
-
- /* copy state into buffer */
- v128_copy(&buffer, &x917_prng.state);
-
- /* apply aes to buffer */
- aes_encrypt(&buffer, x917_prng.key);
-
- /* write data to output */
- *dest++ = buffer.v8[0];
- *dest++ = buffer.v8[1];
- *dest++ = buffer.v8[2];
- *dest++ = buffer.v8[3];
- *dest++ = buffer.v8[4];
- *dest++ = buffer.v8[5];
- *dest++ = buffer.v8[6];
- *dest++ = buffer.v8[7];
- *dest++ = buffer.v8[8];
- *dest++ = buffer.v8[9];
- *dest++ = buffer.v8[10];
- *dest++ = buffer.v8[11];
- *dest++ = buffer.v8[12];
- *dest++ = buffer.v8[13];
- *dest++ = buffer.v8[14];
- *dest++ = buffer.v8[15];
-
- /* exor time into buffer */
- buffer.v32[0] ^= t;
-
- /* encrypt buffer */
- aes_encrypt(&buffer, x917_prng.key);
-
- /* copy buffer into state */
- v128_copy(&x917_prng.state, &buffer);
-
- }
-
- /* if we need to output any more octets, we'll do so now */
- tail_len = len % 16;
- if (tail_len) {
-
- /* exor time into state */
- x917_prng.state.v32[0] ^= t;
-
- /* copy value into buffer */
- v128_copy(&buffer, &x917_prng.state);
-
- /* apply aes to buffer */
- aes_encrypt(&buffer, x917_prng.key);
-
- /* write data to output */
- for (i=0; i < tail_len; i++) {
- *dest++ = buffer.v8[i];
- }
-
- /* now update the state one more time */
-
- /* exor time into buffer */
- buffer.v32[0] ^= t;
-
- /* encrypt buffer */
- aes_encrypt(&buffer, x917_prng.key);
-
- /* copy buffer into state */
- v128_copy(&x917_prng.state, &buffer);
-
- }
-
- return err_status_ok;
-}
-
-err_status_t
-x917_prng_deinit(void) {
-
- return err_status_ok;
-}