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/*
**
** OpenBSD emulation routines
**
** Damien Miller <djm@ibs.com.au>
**
** Copyright 1999 Internet Business Solutions
**
** Permission is hereby granted, free of charge, to any person
** obtaining a copy of this software and associated documentation
** files (the "Software"), to deal in the Software without
** restriction, including without limitation the rights to use, copy,
** modify, merge, publish, distribute, sublicense, and/or sell copies
** of the Software, and to permit persons to whom the Software is
** furnished to do so, subject to the following conditions:
**
** The above copyright notice and this permission notice shall be
** included in all copies or substantial portions of the Software.
**
** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
** KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
** WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
** AND NONINFRINGEMENT. IN NO EVENT SHALL DAMIEN MILLER OR INTERNET
** BUSINESS SOLUTIONS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
** ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
** OR OTHER DEALINGS IN THE SOFTWARE.
**
** Except as contained in this notice, the name of Internet Business
** Solutions shall not be used in advertising or otherwise to promote
** the sale, use or other dealings in this Software without prior
** written authorization from Internet Business Solutions.
**
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <fcntl.h>
#include "xmalloc.h"
#include "ssh.h"
#include "config.h"
#include "helper.h"
#ifndef offsetof
#define offsetof(type, member) ((size_t) &((type *)0)->member)
#endif
#ifndef HAVE_ARC4RANDOM
typedef struct
{
unsigned int s[256];
int i;
int j;
} rc4_t;
void get_random_bytes(unsigned char *buf, int len);
void rc4_key(rc4_t *r, unsigned char *key, int len);
void rc4_getbytes(rc4_t *r, unsigned char *buffer, int len);
static rc4_t *rc4 = NULL;
void rc4_key(rc4_t *r, unsigned char *key, int len)
{
int t;
for(r->i = 0; r->i < 256; r->i++)
r->s[r->i] = r->i;
r->j = 0;
for(r->i = 0; r->i < 256; r->i++)
{
r->j = (r->j + r->s[r->i] + key[r->i % len]) % 256;
t = r->s[r->i];
r->s[r->i] = r->s[r->j];
r->s[r->j] = t;
}
r->i = r->j = 0;
}
void rc4_getbytes(rc4_t *r, unsigned char *buffer, int len)
{
int t;
int c;
c = 0;
while(c < len)
{
r->i = (r->i + 1) % 256;
r->j = (r->j + r->s[r->i]) % 256;
t = r->s[r->i];
r->s[r->i] = r->s[r->j];
r->s[r->j] = t;
t = (r->s[r->i] + r->s[r->j]) % 256;
buffer[c] = r->s[t];
c++;
}
}
unsigned int arc4random(void)
{
unsigned int r;
if (rc4 == NULL)
arc4random_stir();
rc4_getbytes(rc4, (unsigned char *)&r, sizeof(r));
return(r);
}
void arc4random_stir(void)
{
unsigned char rand_buf[32];
if (rc4 == NULL)
rc4 = xmalloc(sizeof(*rc4));
get_random_bytes(rand_buf, sizeof(rand_buf));
rc4_key(rc4, rand_buf, sizeof(rand_buf));
}
void get_random_bytes(unsigned char *buf, int len)
{
static int random_pool;
int c;
#ifdef HAVE_EGD
char egd_message[2] = { 0x02, 0x00 };
struct sockaddr_un addr;
int addr_len;
memset(&addr, '\0', sizeof(addr));
addr.sun_family = AF_UNIX;
/* FIXME: compile time check? */
if (sizeof(RANDOM_POOL) > sizeof(addr.sun_path))
fatal("Random pool path is too long");
strcpy(addr.sun_path, RANDOM_POOL);
addr_len = offsetof(struct sockaddr_un, sun_path) + sizeof(RANDOM_POOL);
random_pool = socket(AF_UNIX, SOCK_STREAM, 0);
if (random_pool == -1)
fatal("Couldn't create AF_UNIX socket: %s", strerror(errno));
if (connect(random_pool, (struct sockaddr*)&addr, addr_len) == -1)
fatal("Couldn't connect to EGD socket \"%s\": %s", addr.sun_path, strerror(errno));
if (len > 255)
fatal("Too many bytes to read from EGD");
/* Send blocking read request to EGD */
egd_message[1] = len;
c = atomicio(write, random_pool, egd_message, sizeof(egd_message));
if (c == -1)
fatal("Couldn't write to EGD socket \"%s\": %s", RANDOM_POOL, strerror(errno));
#else /* HAVE_EGD */
random_pool = open(RANDOM_POOL, O_RDONLY);
if (random_pool == -1)
fatal("Couldn't open random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
#endif /* HAVE_EGD */
c = atomicio(read, random_pool, buf, len);
if (c <= 0)
fatal("Couldn't read from random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
close(random_pool);
}
#endif /* !HAVE_ARC4RANDOM */
#ifndef HAVE_SETPROCTITLE
void setproctitle(const char *fmt, ...)
{
/* FIXME */
}
#endif /* !HAVE_SETPROCTITLE */
#ifndef HAVE_SETENV
int setenv(const char *name, const char *value, int overwrite)
{
char *env_string;
int result;
/* Don't overwrite existing env. var if overwrite is 0 */
if (!overwrite && (getenv(name) != NULL))
return(0);
env_string = xmalloc(strlen(name) + strlen(value) + 2);
sprintf(env_string, "%s=%s", name, value);
result = putenv(env_string);
xfree(env_string);
return(result);
}
#endif /* !HAVE_SETENV */