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      1 /* crypto/rand/rand_egd.c */
      2 /* Written by Ulf Moeller and Lutz Jaenicke for the OpenSSL project. */
      3 /* ====================================================================
      4  * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  *
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  *
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in
     15  *    the documentation and/or other materials provided with the
     16  *    distribution.
     17  *
     18  * 3. All advertising materials mentioning features or use of this
     19  *    software must display the following acknowledgment:
     20  *    "This product includes software developed by the OpenSSL Project
     21  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
     22  *
     23  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
     24  *    endorse or promote products derived from this software without
     25  *    prior written permission. For written permission, please contact
     26  *    openssl-core (at) openssl.org.
     27  *
     28  * 5. Products derived from this software may not be called "OpenSSL"
     29  *    nor may "OpenSSL" appear in their names without prior written
     30  *    permission of the OpenSSL Project.
     31  *
     32  * 6. Redistributions of any form whatsoever must retain the following
     33  *    acknowledgment:
     34  *    "This product includes software developed by the OpenSSL Project
     35  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
     36  *
     37  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
     38  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     39  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     40  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
     41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     43  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     44  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     45  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     46  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     47  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
     48  * OF THE POSSIBILITY OF SUCH DAMAGE.
     49  * ====================================================================
     50  *
     51  * This product includes cryptographic software written by Eric Young
     52  * (eay (at) cryptsoft.com).  This product includes software written by Tim
     53  * Hudson (tjh (at) cryptsoft.com).
     54  *
     55  */
     56 
     57 #include <openssl/e_os2.h>
     58 #include <openssl/rand.h>
     59 #include <openssl/buffer.h>
     60 
     61 /*
     62  * Query the EGD <URL: http://www.lothar.com/tech/crypto/>.
     63  *
     64  * This module supplies three routines:
     65  *
     66  * RAND_query_egd_bytes(path, buf, bytes)
     67  *   will actually query "bytes" bytes of entropy form the egd-socket located
     68  *   at path and will write them to buf (if supplied) or will directly feed
     69  *   it to RAND_seed() if buf==NULL.
     70  *   The number of bytes is not limited by the maximum chunk size of EGD,
     71  *   which is 255 bytes. If more than 255 bytes are wanted, several chunks
     72  *   of entropy bytes are requested. The connection is left open until the
     73  *   query is competed.
     74  *   RAND_query_egd_bytes() returns with
     75  *     -1  if an error occured during connection or communication.
     76  *     num the number of bytes read from the EGD socket. This number is either
     77  *         the number of bytes requested or smaller, if the EGD pool is
     78  *         drained and the daemon signals that the pool is empty.
     79  *   This routine does not touch any RAND_status(). This is necessary, since
     80  *   PRNG functions may call it during initialization.
     81  *
     82  * RAND_egd_bytes(path, bytes) will query "bytes" bytes and have them
     83  *   used to seed the PRNG.
     84  *   RAND_egd_bytes() is a wrapper for RAND_query_egd_bytes() with buf=NULL.
     85  *   Unlike RAND_query_egd_bytes(), RAND_status() is used to test the
     86  *   seed status so that the return value can reflect the seed state:
     87  *     -1  if an error occured during connection or communication _or_
     88  *         if the PRNG has still not received the required seeding.
     89  *     num the number of bytes read from the EGD socket. This number is either
     90  *         the number of bytes requested or smaller, if the EGD pool is
     91  *         drained and the daemon signals that the pool is empty.
     92  *
     93  * RAND_egd(path) will query 255 bytes and use the bytes retreived to seed
     94  *   the PRNG.
     95  *   RAND_egd() is a wrapper for RAND_egd_bytes() with numbytes=255.
     96  */
     97 
     98 #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_MSDOS) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_NETWARE) || defined(OPENSSL_SYS_VOS) || defined(OPENSSL_SYS_BEOS)
     99 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
    100 	{
    101 	return(-1);
    102 	}
    103 int RAND_egd(const char *path)
    104 	{
    105 	return(-1);
    106 	}
    107 
    108 int RAND_egd_bytes(const char *path,int bytes)
    109 	{
    110 	return(-1);
    111 	}
    112 #else
    113 #include <openssl/opensslconf.h>
    114 #include OPENSSL_UNISTD
    115 #include <sys/types.h>
    116 #include <sys/socket.h>
    117 #ifndef NO_SYS_UN_H
    118 # ifdef OPENSSL_SYS_VXWORKS
    119 #   include <streams/un.h>
    120 # else
    121 #   include <sys/un.h>
    122 # endif
    123 #else
    124 struct	sockaddr_un {
    125 	short	sun_family;		/* AF_UNIX */
    126 	char	sun_path[108];		/* path name (gag) */
    127 };
    128 #endif /* NO_SYS_UN_H */
    129 #include <string.h>
    130 #include <errno.h>
    131 
    132 #ifndef offsetof
    133 #  define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
    134 #endif
    135 
    136 int RAND_query_egd_bytes(const char *path, unsigned char *buf, int bytes)
    137 	{
    138 	int ret = 0;
    139 	struct sockaddr_un addr;
    140 	int len, num, numbytes;
    141 	int fd = -1;
    142 	int success;
    143 	unsigned char egdbuf[2], tempbuf[255], *retrievebuf;
    144 
    145 	memset(&addr, 0, sizeof(addr));
    146 	addr.sun_family = AF_UNIX;
    147 	if (strlen(path) >= sizeof(addr.sun_path))
    148 		return (-1);
    149 	BUF_strlcpy(addr.sun_path,path,sizeof addr.sun_path);
    150 	len = offsetof(struct sockaddr_un, sun_path) + strlen(path);
    151 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
    152 	if (fd == -1) return (-1);
    153 	success = 0;
    154 	while (!success)
    155 	    {
    156 	    if (connect(fd, (struct sockaddr *)&addr, len) == 0)
    157 	       success = 1;
    158 	    else
    159 		{
    160 		switch (errno)
    161 		    {
    162 #ifdef EINTR
    163 		    case EINTR:
    164 #endif
    165 #ifdef EAGAIN
    166 		    case EAGAIN:
    167 #endif
    168 #ifdef EINPROGRESS
    169 		    case EINPROGRESS:
    170 #endif
    171 #ifdef EALREADY
    172 		    case EALREADY:
    173 #endif
    174 			/* No error, try again */
    175 			break;
    176 #ifdef EISCONN
    177 		    case EISCONN:
    178 			success = 1;
    179 			break;
    180 #endif
    181 		    default:
    182 			goto err;	/* failure */
    183 		    }
    184 		}
    185 	    }
    186 
    187 	while(bytes > 0)
    188 	    {
    189 	    egdbuf[0] = 1;
    190 	    egdbuf[1] = bytes < 255 ? bytes : 255;
    191 	    numbytes = 0;
    192 	    while (numbytes != 2)
    193 		{
    194 	        num = write(fd, egdbuf + numbytes, 2 - numbytes);
    195 	        if (num >= 0)
    196 		    numbytes += num;
    197 	    	else
    198 		    {
    199 		    switch (errno)
    200 		    	{
    201 #ifdef EINTR
    202 		    	case EINTR:
    203 #endif
    204 #ifdef EAGAIN
    205 		    	case EAGAIN:
    206 #endif
    207 			    /* No error, try again */
    208 			    break;
    209 		    	default:
    210 			    ret = -1;
    211 			    goto err;	/* failure */
    212 			}
    213 		    }
    214 		}
    215 	    numbytes = 0;
    216 	    while (numbytes != 1)
    217 		{
    218 	        num = read(fd, egdbuf, 1);
    219 	        if (num == 0)
    220 			goto err;	/* descriptor closed */
    221 		else if (num > 0)
    222 		    numbytes += num;
    223 	    	else
    224 		    {
    225 		    switch (errno)
    226 		    	{
    227 #ifdef EINTR
    228 		    	case EINTR:
    229 #endif
    230 #ifdef EAGAIN
    231 		    	case EAGAIN:
    232 #endif
    233 			    /* No error, try again */
    234 			    break;
    235 		    	default:
    236 			    ret = -1;
    237 			    goto err;	/* failure */
    238 			}
    239 		    }
    240 		}
    241 	    if(egdbuf[0] == 0)
    242 		goto err;
    243 	    if (buf)
    244 		retrievebuf = buf + ret;
    245 	    else
    246 		retrievebuf = tempbuf;
    247 	    numbytes = 0;
    248 	    while (numbytes != egdbuf[0])
    249 		{
    250 	        num = read(fd, retrievebuf + numbytes, egdbuf[0] - numbytes);
    251 		if (num == 0)
    252 			goto err;	/* descriptor closed */
    253 	        else if (num > 0)
    254 		    numbytes += num;
    255 	    	else
    256 		    {
    257 		    switch (errno)
    258 		    	{
    259 #ifdef EINTR
    260 		    	case EINTR:
    261 #endif
    262 #ifdef EAGAIN
    263 		    	case EAGAIN:
    264 #endif
    265 			    /* No error, try again */
    266 			    break;
    267 		    	default:
    268 			    ret = -1;
    269 			    goto err;	/* failure */
    270 			}
    271 		    }
    272 		}
    273 	    ret += egdbuf[0];
    274 	    bytes -= egdbuf[0];
    275 	    if (!buf)
    276 		RAND_seed(tempbuf, egdbuf[0]);
    277 	    }
    278  err:
    279 	if (fd != -1) close(fd);
    280 	return(ret);
    281 	}
    282 
    283 
    284 int RAND_egd_bytes(const char *path, int bytes)
    285 	{
    286 	int num, ret = 0;
    287 
    288 	num = RAND_query_egd_bytes(path, NULL, bytes);
    289 	if (num < 1) goto err;
    290 	if (RAND_status() == 1)
    291 	    ret = num;
    292  err:
    293 	return(ret);
    294 	}
    295 
    296 
    297 int RAND_egd(const char *path)
    298 	{
    299 	return (RAND_egd_bytes(path, 255));
    300 	}
    301 
    302 
    303 #endif
    304