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diff --git a/source/lib/genrand.c b/source/lib/genrand.c
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+/*
+ Unix SMB/Netbios implementation.
+ Version 1.9.
+
+ Functions to create reasonable random numbers for crypto use.
+
+ Copyright (C) Jeremy Allison 1998
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+extern int DEBUGLEVEL;
+static uint32 counter = 0;
+
+/****************************************************************
+get a 16 byte hash from the contents of a file
+Note that the hash is not initialised.
+*****************************************************************/
+static void do_filehash(char *fname, unsigned char *hash)
+{
+ unsigned char buf[1011]; /* deliberate weird size */
+ unsigned char tmp_md4[16];
+ int fd, n;
+
+ fd = open(fname,O_RDONLY);
+ if (fd == -1) return;
+
+ while ((n = read(fd, (char *)buf, sizeof(buf))) > 0) {
+ mdfour(tmp_md4, buf, n);
+ for (n=0;n<16;n++)
+ hash[n] ^= tmp_md4[n];
+ }
+ close(fd);
+}
+
+
+
+/****************************************************************
+ Try and get a seed by looking at the atimes of files in a given
+ directory. XOR them into the buf array.
+*****************************************************************/
+
+static void do_dirrand(char *name, unsigned char *buf, int buf_len)
+{
+ void *dp = dos_opendir(name);
+ pstring fullname;
+ int len_left;
+ int fullname_len;
+ char *pos;
+
+ pstrcpy(fullname, name);
+ fullname_len = strlen(fullname);
+
+ if(fullname_len + 2 > sizeof(pstring))
+ return;
+
+ if(fullname[fullname_len] != '/') {
+ fullname[fullname_len] = '/';
+ fullname[fullname_len+1] = '\0';
+ fullname_len = strlen(fullname);
+ }
+
+ len_left = sizeof(pstring) - fullname_len - 1;
+ pos = &fullname[fullname_len];
+
+ if(dp != NULL) {
+ char *p;
+
+ while ((p = readdirname(dp))) {
+ SMB_STRUCT_STAT st;
+
+ if(strlen(p) <= len_left)
+ pstrcpy(pos, p);
+
+ if(dos_stat(fullname,&st) == 0) {
+ SIVAL(buf, ((counter * 4)%(buf_len-4)),
+ IVAL(buf,((counter * 4)%(buf_len-4))) ^ st.st_atime);
+ counter++;
+ DEBUG(10,("do_dirrand: value from file %s.\n", fullname));
+ }
+ }
+ closedir(dp);
+ }
+}
+
+/**************************************************************
+ Try and get a good random number seed. Try a number of
+ different factors. Firstly, try /dev/random and try and
+ read from this. If this fails iterate through /tmp and
+ /dev and XOR all the file timestamps. Next add in
+ a hash of the contents of /etc/shadow and the smb passwd
+ file and a combination of pid and time of day (yes I know this
+ sucks :-). Finally md4 the result.
+
+ The result goes in a 16 byte buffer passed from the caller
+**************************************************************/
+
+static uint32 do_reseed(unsigned char *md4_outbuf)
+{
+ unsigned char md4_inbuf[40];
+ BOOL got_random = False;
+ uint32 v1, v2, ret;
+ int fd;
+ struct timeval tval;
+ pid_t mypid;
+ struct passwd *pw;
+
+ memset(md4_inbuf, '\0', sizeof(md4_inbuf));
+
+ fd = open( "/dev/random", O_RDONLY);
+ if(fd >= 0) {
+ /*
+ * We can use /dev/random !
+ */
+ if(read(fd, md4_inbuf, 40) == 40) {
+ got_random = True;
+ DEBUG(10,("do_reseed: got 40 bytes from /dev/random.\n"));
+ }
+ close(fd);
+ }
+
+ if(!got_random) {
+ /*
+ * /dev/random failed - try /tmp and /dev for timestamps.
+ */
+ do_dirrand("/tmp", md4_inbuf, sizeof(md4_inbuf));
+ do_dirrand("/dev", md4_inbuf, sizeof(md4_inbuf));
+ }
+
+ /* possibly add in some secret file contents */
+ do_filehash("/etc/shadow", &md4_inbuf[0]);
+ do_filehash(lp_smb_passwd_file(), &md4_inbuf[16]);
+
+ /* add in the root encrypted password. On any system where security is taken
+ seriously this will be secret */
+ pw = getpwnam("root");
+ if (pw && pw->pw_passwd) {
+ int i;
+ unsigned char md4_tmp[16];
+ mdfour(md4_tmp, (unsigned char *)pw->pw_passwd, strlen(pw->pw_passwd));
+ for (i=0;i<16;i++)
+ md4_inbuf[8+i] ^= md4_tmp[i];
+ }
+
+ /*
+ * Finally add the counter, time of day, and pid.
+ */
+ GetTimeOfDay(&tval);
+ mypid = getpid();
+ v1 = (counter++) + mypid + tval.tv_sec;
+ v2 = (counter++) * mypid + tval.tv_usec;
+
+ SIVAL(md4_inbuf, 32, v1 ^ IVAL(md4_inbuf, 32));
+ SIVAL(md4_inbuf, 36, v2 ^ IVAL(md4_inbuf, 36));
+
+ mdfour(md4_outbuf, md4_inbuf, sizeof(md4_inbuf));
+
+ /*
+ * Return a 32 bit int created from XORing the
+ * 16 bit return buffer.
+ */
+
+ ret = IVAL(md4_outbuf, 0);
+ ret ^= IVAL(md4_outbuf, 4);
+ ret ^= IVAL(md4_outbuf, 8);
+ return (ret ^ IVAL(md4_outbuf, 12));
+}
+
+/*******************************************************************
+ Interface to the (hopefully) good crypto random number generator.
+********************************************************************/
+
+void generate_random_buffer( unsigned char *out, int len, BOOL re_seed)
+{
+ static BOOL done_reseed = False;
+ static unsigned char md4_buf[16];
+ unsigned char tmp_buf[16];
+ unsigned char *p;
+
+ if(!done_reseed || re_seed) {
+ srandom(do_reseed(md4_buf));
+ done_reseed = True;
+ }
+
+ /*
+ * Generate random numbers in chunks of 64 bytes,
+ * then md4 them & copy to the output buffer.
+ * Added XOR with output from random, seeded
+ * by the original md4_buf. This is to stop the
+ * output from this function being the previous
+ * md4_buf md4'ed. The output from this function
+ * is often output onto the wire, and so it should
+ * not be possible to guess the next output from
+ * this function based on the previous output.
+ * XORing in the output from random(), seeded by
+ * the original md4 hash should stop this. JRA.
+ */
+
+ p = out;
+ while(len > 0) {
+ int i;
+ int copy_len = len > 16 ? 16 : len;
+ mdfour(tmp_buf, md4_buf, sizeof(md4_buf));
+ memcpy(md4_buf, tmp_buf, sizeof(md4_buf));
+ /* XOR in output from random(). */
+ for(i = 0; i < 4; i++)
+ SIVAL(tmp_buf, i*4, (IVAL(tmp_buf, i*4) ^ (uint32)random()));
+ memcpy(p, tmp_buf, copy_len);
+ p += copy_len;
+ len -= copy_len;
+ }
+}
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