diff options
Diffstat (limited to 'crypto/bn/bn_rand.c')
-rw-r--r-- | crypto/bn/bn_rand.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/crypto/bn/bn_rand.c b/crypto/bn/bn_rand.c new file mode 100644 index 0000000000..e3530a5bf2 --- /dev/null +++ b/crypto/bn/bn_rand.c @@ -0,0 +1,121 @@ +/* crypto/bn/bn_rand.c */ +/* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com) + * All rights reserved. + * + * This package is an SSL implementation written + * by Eric Young (eay@cryptsoft.com). + * The implementation was written so as to conform with Netscapes SSL. + * + * This library is free for commercial and non-commercial use as long as + * the following conditions are aheared to. The following conditions + * apply to all code found in this distribution, be it the RC4, RSA, + * lhash, DES, etc., code; not just the SSL code. The SSL documentation + * included with this distribution is covered by the same copyright terms + * except that the holder is Tim Hudson (tjh@cryptsoft.com). + * + * Copyright remains Eric Young's, and as such any Copyright notices in + * the code are not to be removed. + * If this package is used in a product, Eric Young should be given attribution + * as the author of the parts of the library used. + * This can be in the form of a textual message at program startup or + * in documentation (online or textual) provided with the package. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * "This product includes cryptographic software written by + * Eric Young (eay@cryptsoft.com)" + * The word 'cryptographic' can be left out if the rouines from the library + * being used are not cryptographic related :-). + * 4. If you include any Windows specific code (or a derivative thereof) from + * the apps directory (application code) you must include an acknowledgement: + * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" + * + * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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. + * + * The licence and distribution terms for any publically available version or + * derivative of this code cannot be changed. i.e. this code cannot simply be + * copied and put under another distribution licence + * [including the GNU Public Licence.] + */ + +#include <stdio.h> +#include <time.h> +#include "cryptlib.h" +#include "bn_lcl.h" +#include "rand.h" + +int BN_rand(rnd, bits, top, bottom) +BIGNUM *rnd; +int bits; +int top; +int bottom; + { + unsigned char *buf=NULL; + int ret=0,bit,bytes,mask; + time_t tim; + + bytes=(bits+7)/8; + bit=(bits-1)%8; + mask=0xff<<bit; + + buf=(unsigned char *)Malloc(bytes); + if (buf == NULL) + { + BNerr(BN_F_BN_RAND,ERR_R_MALLOC_FAILURE); + goto err; + } + + /* make a random number and set the top and bottom bits */ + time(&tim); + RAND_seed((unsigned char *)&tim,sizeof(tim)); + + RAND_bytes(buf,(int)bytes); + if (top) + { + if (bit == 0) + { + buf[0]=1; + buf[1]|=0x80; + } + else + { + buf[0]|=(3<<(bit-1)); + buf[0]&= ~(mask<<1); + } + } + else + { + buf[0]|=(1<<bit); + buf[0]&= ~(mask<<1); + } + if (bottom) /* set bottom bits to whatever odd is */ + buf[bytes-1]|=1; + if (!BN_bin2bn(buf,bytes,rnd)) goto err; + ret=1; +err: + if (buf != NULL) + { + memset(buf,0,bytes); + Free(buf); + } + return(ret); + } + |