From 414cb2bec5ccbf389086e7fe97fb28410df6c30b Mon Sep 17 00:00:00 2001
From: TLINDEN <git@daemon.de>
Date: Sat, 1 Aug 2015 20:54:10 +0200
Subject: [PATCH] re-organized source, added Makefile, better Readme, added
 manpage

---
 Makefile      |  49 +++++++
 README.md     |  67 ++++++++--
 dice.c        | 352 --------------------------------------------------
 dicepwgen.1   | 193 +++++++++++++++++++++++++++
 dicepwgen.c   | 146 +++++++++++++++++++++
 dicepwgen.h   |  48 +++++++
 dicepwgen.pod |  61 +++++++++
 dictfile.c    | 139 ++++++++++++++++++++
 dictfile.h    |  40 ++++++
 tossing.c     | 124 ++++++++++++++++++
 tossing.h     |  42 ++++++
 11 files changed, 900 insertions(+), 361 deletions(-)
 create mode 100644 Makefile
 delete mode 100644 dice.c
 create mode 100644 dicepwgen.1
 create mode 100644 dicepwgen.c
 create mode 100644 dicepwgen.h
 create mode 100644 dicepwgen.pod
 create mode 100644 dictfile.c
 create mode 100644 dictfile.h
 create mode 100644 tossing.c
 create mode 100644 tossing.h

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..ae357e6
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,49 @@
+#
+#    This file is part of dicepwgen
+#
+#    Copyright (C) 2015 T.v.Dein.
+#
+#    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 3 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, see <http://www.gnu.org/licenses/>.
+#
+#    You can contact me by mail: <tom AT vondein DOT org>.
+
+CFLAGS = -Wall -Wextra -Werror -O1 -g
+LDFLAGS=
+OBJS   = dicepwgen.o dictfile.o tossing.o
+DST    = dicepwgen
+PREFIX = /usr/local
+UID    = root
+GID    = 0
+MAN    = dicepwgen.1
+POD    = dicepwgen.pod
+
+all: $(DST)
+
+$(DST): $(OBJS)
+	gcc $(OBJS) -o $(DST)
+
+%.o: %.c
+	gcc -c $(CFLAGS) $*.c -o $*.o
+
+clean:
+	rm -f *.o $(DST)
+
+man:
+	pod2man $(POD) > $(MAN)
+
+install: $(DST)
+	install -d -o $(UID) -g $(GID) $(PREFIX)/sbin
+	install -d -o $(UID) -g $(GID) $(PREFIX)/man/man1
+	install -o $(UID) -g $(GID) -m 555 $(DST) $(PREFIX)/sbin/
+	install -o $(UID) -g $(GID) -m 444 $(MAN) $(PREFIX)/man/man1/
diff --git a/README.md b/README.md
index 55d349c..2b5ed81 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,46 @@
-# diceware
-A diceware password generator
+## dicepwgen - A diceware password generator
 
-# build
+This is the README file for the password generator dicepwgen.
 
-gcc dice.c -o dice
+## Documentation
 
-# use
+You can read the documentation without installing the
+software:
+
+    perldoc udpxd.pod
+
+If it is already installed, you can read the manual page:
+
+    man udpxd
+
+## Installation
+
+This software doesn't have eny external dependencies, but
+you need either BSD make or GNU make installed to build it.
+
+First you need to check out the source code. Skip this, if
+you have already done so:
+
+    git clone git@github.com:TLINDEN/diceware.git
+
+Next, change into the newly created directory 'diceware' and
+compile the source code:
+
+    cd diceware
+    make
+
+To install, type this command:
+
+    sudo make install
+
+This will install the binary to `$PREFIX/sbin/dicepwgen` and
+the manual page to `$PREFIX/man/man1/dicepwgen.1`. You can
+modify `$PREFIX` during installation time like this:
+
+   make install PREFIX=/opt
+
+
+## Usage
 
 ```
 Usage: dice [-tcfvh]
@@ -18,9 +53,23 @@ Options:
 -h               Print this help screen
 ```
 
-# license
+## Getting help
 
-GPLv3
+Although I'm happy to hear from udpxd users in private email,
+that's the best way for me to forget to do something.
 
-# author
-Thomas von Dein
+In order to report a bug, unexpected behavior, feature requests
+or to submit a patch, please open an issue on github:
+https://github.com/TLINDEN/diceware/issues.
+
+## License
+
+This software is licensed under the GNU GENERAL PUBLIC LICENSE version 3.
+
+## Author
+
+T.v.Dein <tom AT vondein DOT org>
+
+## Project homepage
+
+https://github.com/TLINDEN/diceware
diff --git a/dice.c b/dice.c
deleted file mode 100644
index 3644307..0000000
--- a/dice.c
+++ /dev/null
@@ -1,352 +0,0 @@
-#include <stdio.h>
-#include <unistd.h>
-#include <getopt.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <string.h>
-#include <ctype.h>
-
-#define  DICTFILE "/usr/share/dict/american-english"
-#define  VERSION  "1.0"
-#define  RLEN     1024
-
-int humantoss = 0;
-int WMIN      = 5;
-int WMAX      = 10;
-
-int usage() {
-  fprintf(stderr,
-	  "Generate a random diceware passphrase\n"
-	  "Usage: dice [-cfvh]\n"
-	  "Options: \n"
-	  "-t --humantoss            Asks interactively for tossed dices\n"
-	  "-c --wordcount <count>    Number of words (default: 4)\n"
-	  "-f --dictfile <dictfile>  Dictionary file to use (default:\n"
-	  "                          /usr/share/dict/american-english)\n"
-	  "-l --minlen <count>       Minimum word len (default: 5)\n"
-	  "-m --maxlen <count>       Maximum word len (default: 10)\n"
-	  "-v --version              Print program version\n"
-	  "-h -? --help              Print this help screen\n"
-	  );
-  return 1;
-}
-
-unsigned char *toss(int count) {
-  /*
-    toss <count> dices. if the global humandice is enabled (option -t),
-    then ask the human to toss dices and enter the numbers interactively.
-    otherwise generate tosses from /dev/random.
-   */
-  
-  FILE *RAND;
-  int i;
-  int pos = 0;
-  uint8_t onedice;
-  unsigned char *tosses = NULL;
-  unsigned char *rand = NULL;
-  size_t len;
-  ssize_t linelen;
- 
-  if(humantoss) {
-    char *line = NULL;
-    char digit[2];
-    digit[1] = '\0';
-   
-  RETRY:
-    fprintf(stderr, "enter 5 digits, each between 1-6\n");
-    linelen = getline(&line, &len, stdin);
-    tosses = malloc((size_t)count);
-    
-    if(linelen < 6) /* 5 digits max allowed */
-      goto RETRY;
-
-    for(i=0; i<count; i++) { /* only digits allowed */
-      if(isdigit(line[i]) == 0)
-	goto RETRY;
-
-      digit[0] = line[i];
-      onedice = atoi(digit);
-
-      if (onedice < 1 || onedice > 6) /* no dice digit */
-	goto RETRY;
-
-      tosses[i] = onedice;
-    }
-    free(line);
-  }
-  else {
-    rand = malloc(RLEN);
- 
-    if((RAND = fopen("/dev/urandom", "rb")) == NULL) {
-      perror("Could not open /dev/urandom");
-    }
-
-    fread(rand, RLEN, 1, RAND);
-    fclose(RAND);
-
-    tosses = malloc((size_t)count);
-    
-    for(i=0; i<RLEN; i++) {
-      onedice = rand[i];
-      onedice &= 7; /* only use the last 3 bits, 0-7 */
-      onedice %= 6; /* 6 is the max */
-      if(onedice >= 1 && onedice <= 6) {
-	tosses[pos] = onedice;
-	pos++;
-      }
-      if(pos == count)
-	break;
-    }
-    free(rand);
-  }
- 
-  return tosses;
-}
-
-int rand_lim(int limit) {
-  /*
-    return a random number in the range [0..limit)
-   */
-
-    int divisor = RAND_MAX/limit;
-    int retval;
-
-    do { 
-        retval = rand() / divisor;
-    } while (retval == limit);
-
-    return retval;
-}
-
-int *incr_dicedigit(int *digits) {
-  /*
-    increment an array of dice digits, we expect the first to
-    be a multiple of 10000, the 2nd a multiple of 1000 and so on.
-  */
-  if(digits[4] == 6) {
-    digits[4] = 1;
-    if(digits[3] == 60) {
-      digits[3] = 10;
-      if(digits[2] == 600) {
-	digits[2] = 100;
-	if(digits[1] == 6000) {
-	  digits[1] = 1000;
-	  digits[0] += 10000; /* may overflow to 71111, must be catched by caller */
-	}
-	else
-	  digits[1] += 1000;
-      }
-      else
-	digits[2] += 100;
-    }
-    else
-      digits[3] += 10;
-  }
-  else
-    digits[4]++;
-
-  return digits;
-}
-
-int get_dicenum(int *digits) {
-  /*
-    get the actual number of an array of dice digits
-  */
-  int i = 0;
-  int pos = 0;
-  for(i=0; i<5; i++)
-    pos += digits[i];
-
-  return pos;
-}
-
-
-char **fetch_dict(char *dictfile) {
-  /*
-    read in the dictionary file. we generate an array of max
-    66666 entries from the dictionary, each entry's index will
-    be a dice number (1 <=> 6). to enhance randomness, we jump
-    over a number of lines (1-32 lines) and start from the beginning
-    of the file if we reach the end before our array is full.
-  */
-
-  char **words;
-  int pos, i, next, jump;
-  char *line = NULL;
-  size_t len = 0;
-  ssize_t linelen;
-  FILE *DICT;
-  int *digits;
-
-  if((DICT = fopen(dictfile, "rb")) == NULL) {
-    perror("Could not open dictfile");
-  }
-
-  words = malloc(66666 * sizeof(char *));
-  digits = malloc(5);
-  jump = rand_lim(32);
-  
-  digits[0] = 10000;
-  digits[1] =  1000;
-  digits[2] =   100;
-  digits[3] =    10;
-  digits[4] =     1;
-
-  pos   = 11111;
-  next = 0;
-
-  for(i=0; i<6666; i++)
-    words[i] = NULL;
-
-  
- LOOP:
-  while ((linelen = getline(&line, &len, DICT)) != -1) {
-    if(jump > 0) {
-      jump--;
-      continue;
-    }
-    else {
-      jump = rand_lim(32);
-    }
-    if(linelen >= WMIN+1 && linelen <= WMAX+1) {
-      line[linelen-1] = '\0'; /* remove newline */
-
-      for(i=0; i<linelen-1; i++) {
-	if(isalpha((int)line[i]) == 0) {
-	  next = 1;
-	  break;
-	}
-      }
-
-      if(next) {
-	next = 0;
-	continue;
-      }
-      
-      words[pos] = malloc(linelen);
-      strncpy( words[pos], line, linelen);
-      //fprintf(stdout, "%d: %s\n", pos, line);
-      
-      digits = incr_dicedigit(digits);
-      pos = get_dicenum(digits);
-
-      /* this is what pos gets next after 66666, which is max reachable with 5 dices */
-      if(pos == 71111)
-	break;
-    } /* endif word 4<=>10 */
-  } /* while read */
-
-  if(pos < 66666) {
-    fseek(DICT, 0L, SEEK_SET);
-    goto LOOP;
-  }
-  
-  fclose(DICT);
-  free(line);
-  free(digits);
-
-  return words;
-}
-
-void getwords(char *dictfile, int count) {
-  /*
-    initiate dice tossing, extract matching number of words
-    froom the wordlist and print it.
-   */
-  char **words;
-  int i, pos, one, two, three, four, five;
-  int *tossed;
-  unsigned char *tosses;
-  
-  words = fetch_dict(dictfile);
-
-  tossed = malloc(count * sizeof(int));
-  
-  for(i=0; i<count; i++) {
-    tosses = toss(5);
-
-    one    = tosses[0] * 10000;
-    two    = tosses[1] *  1000;
-    three  = tosses[2] *   100;
-    four   = tosses[3] *    10;
-    five   = tosses[4];
-    
-    pos = one + two + three + four + five;
-
-    tossed[i] = pos;
-
-    free(tosses);
-  }
-
-  for(i=0; i<count; i++) {
-    fprintf(stdout, "%s ", words[tossed[i]]);
-  }
-
-  fprintf(stdout, "\n");
-  
-  free(tossed);
-
-  for(i=0; i<6666; i++)
-    if(words[i] != NULL)
-      free(words[i]);
-
-  free(words);
-}
-
-int main (int argc, char **argv)  {
-  int count = 4;
-  char *dictfile = NULL;
-  unsigned char *tosses = NULL;
-  int opt;
-  
-  static struct option longopts[] = {
-    { "wordcount", required_argument, NULL,           'c' },
-    { "minlen",    required_argument, NULL,           'l' },
-    { "maxlen",    required_argument, NULL,           'm' },
-    { "humantoss", required_argument, NULL,           't' },    
-    { "dictfile",  required_argument, NULL,           'f' },
-    { "version",   no_argument,       NULL,           'v' },
-    { "help",      no_argument,       NULL,           'h' },
-  };
-
-   while ((opt = getopt_long(argc, argv, "l:m:tf:c:vh?", longopts, NULL)) != -1) {
-     switch (opt) {
-     case 'v':
-       fprintf(stderr, "This is %s version %s\n", argv[0], VERSION);
-       return 1;
-       break;
-     case 'h':
-     case '?':
-       return usage();
-       break;
-     case 'c':
-       count = atoi(optarg);
-       break;
-     case 'l':
-       WMIN = atoi(optarg);
-       break;
-     case 'm':
-       WMAX = atoi(optarg);
-       break;
-     case 't':
-       humantoss = 1;
-       break;
-     case 'f':
-       dictfile = malloc(strlen(optarg));
-       strncpy(dictfile, optarg, strlen(optarg));
-       break;
-     default:
-      return usage();
-      break;
-     }
-   }
-
-
-   if(dictfile == NULL) {
-     dictfile = DICTFILE;
-   }
-   
-   getwords(dictfile, count);
-
-   return 0;
-}
diff --git a/dicepwgen.1 b/dicepwgen.1
new file mode 100644
index 0000000..0760ab2
--- /dev/null
+++ b/dicepwgen.1
@@ -0,0 +1,193 @@
+.\" Automatically generated by Pod::Man 2.27 (Pod::Simple 3.28)
+.\"
+.\" Standard preamble:
+.\" ========================================================================
+.de Sp \" Vertical space (when we can't use .PP)
+.if t .sp .5v
+.if n .sp
+..
+.de Vb \" Begin verbatim text
+.ft CW
+.nf
+.ne \\$1
+..
+.de Ve \" End verbatim text
+.ft R
+.fi
+..
+.\" Set up some character translations and predefined strings.  \*(-- will
+.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
+.\" double quote, and \*(R" will give a right double quote.  \*(C+ will
+.\" give a nicer C++.  Capital omega is used to do unbreakable dashes and
+.\" therefore won't be available.  \*(C` and \*(C' expand to `' in nroff,
+.\" nothing in troff, for use with C<>.
+.tr \(*W-
+.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
+.ie n \{\
+.    ds -- \(*W-
+.    ds PI pi
+.    if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
+.    if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\"  diablo 12 pitch
+.    ds L" ""
+.    ds R" ""
+.    ds C` ""
+.    ds C' ""
+'br\}
+.el\{\
+.    ds -- \|\(em\|
+.    ds PI \(*p
+.    ds L" ``
+.    ds R" ''
+.    ds C`
+.    ds C'
+'br\}
+.\"
+.\" Escape single quotes in literal strings from groff's Unicode transform.
+.ie \n(.g .ds Aq \(aq
+.el       .ds Aq '
+.\"
+.\" If the F register is turned on, we'll generate index entries on stderr for
+.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
+.\" entries marked with X<> in POD.  Of course, you'll have to process the
+.\" output yourself in some meaningful fashion.
+.\"
+.\" Avoid warning from groff about undefined register 'F'.
+.de IX
+..
+.nr rF 0
+.if \n(.g .if rF .nr rF 1
+.if (\n(rF:(\n(.g==0)) \{
+.    if \nF \{
+.        de IX
+.        tm Index:\\$1\t\\n%\t"\\$2"
+..
+.        if !\nF==2 \{
+.            nr % 0
+.            nr F 2
+.        \}
+.    \}
+.\}
+.rr rF
+.\"
+.\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
+.\" Fear.  Run.  Save yourself.  No user-serviceable parts.
+.    \" fudge factors for nroff and troff
+.if n \{\
+.    ds #H 0
+.    ds #V .8m
+.    ds #F .3m
+.    ds #[ \f1
+.    ds #] \fP
+.\}
+.if t \{\
+.    ds #H ((1u-(\\\\n(.fu%2u))*.13m)
+.    ds #V .6m
+.    ds #F 0
+.    ds #[ \&
+.    ds #] \&
+.\}
+.    \" simple accents for nroff and troff
+.if n \{\
+.    ds ' \&
+.    ds ` \&
+.    ds ^ \&
+.    ds , \&
+.    ds ~ ~
+.    ds /
+.\}
+.if t \{\
+.    ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
+.    ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
+.    ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
+.    ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
+.    ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
+.    ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
+.\}
+.    \" troff and (daisy-wheel) nroff accents
+.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
+.ds 8 \h'\*(#H'\(*b\h'-\*(#H'
+.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
+.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
+.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
+.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
+.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
+.ds ae a\h'-(\w'a'u*4/10)'e
+.ds Ae A\h'-(\w'A'u*4/10)'E
+.    \" corrections for vroff
+.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
+.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
+.    \" for low resolution devices (crt and lpr)
+.if \n(.H>23 .if \n(.V>19 \
+\{\
+.    ds : e
+.    ds 8 ss
+.    ds o a
+.    ds d- d\h'-1'\(ga
+.    ds D- D\h'-1'\(hy
+.    ds th \o'bp'
+.    ds Th \o'LP'
+.    ds ae ae
+.    ds Ae AE
+.\}
+.rm #[ #] #H #V #F C
+.\" ========================================================================
+.\"
+.IX Title "DICEPWGEN 1"
+.TH DICEPWGEN 1 "2015-08-01" "perl v5.18.2" "User Contributed Perl Documentation"
+.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
+.\" way too many mistakes in technical documents.
+.if n .ad l
+.nh
+.SH "NAME"
+dicepwgen \- A diceware password generator
+.SH "SYNOPSIS"
+.IX Header "SYNOPSIS"
+.Vb 10
+\& Usage: dice [\-cfvh]
+\& Options: 
+\& \-t \-\-humantoss            Asks interactively for tossed dices
+\& \-c \-\-wordcount <count>    Number of words (default: 4)
+\& \-f \-\-dictfile <dictfile>  Dictionary file to use (default:
+\&                           /usr/share/dict/american\-english)
+\& \-l \-\-minlen <count>       Minimum word len (default: 5)
+\& \-m \-\-maxlen <count>       Maximum word len (default: 10)
+\& \-v \-\-version              Print program version
+\& \-h \-? \-\-help              Print this help screen
+.Ve
+.SH "DESCRIPTION"
+.IX Header "DESCRIPTION"
+dicepwgen generates a diceware password using a dictionary
+file. By default it uses pseudo random dice tosses, but
+it is also possible to use real dices and enter the numbers
+by using the option \fB\-t\fR.
+.PP
+The option \fB\-c\fR can be used to tweak the number of words
+to output. The options \fB\-l\fR and \fB\-m\fR can be used to tweak
+minimum and maximum word length.
+.PP
+You can tell dicepwgen to use another dictionary file with
+the option \fB\-f\fR.
+.PP
+The program only uses words which contain 7bit \s-1ASCII\s0 letters
+(a\-zA-Z), which are easier for password usage anyway.
+.SH "FILES"
+.IX Header "FILES"
+\&\fB/usr/share/dict/american\-english\fR: default dictionary file.
+.SH "SEE ALSO"
+.IX Header "SEE ALSO"
+<http://world.std.com/~reinhold/diceware.html>
+.PP
+<https://xkcd.com/936/>.
+.SH "BUGS"
+.IX Header "BUGS"
+In order to report a bug, unexpected behavior, feature requests
+or to submit a patch, please open an issue on github:
+<https://github.com/TLINDEN/diceware/issues>.
+.SH "LICENSE"
+.IX Header "LICENSE"
+This software is licensed under the \s-1GNU GENERAL PUBLIC LICENSE\s0 version 3.
+.PP
+Copyright (c) 2015 by T. v. Dein.
+.SH "AUTHORS"
+.IX Header "AUTHORS"
+T.v.Dein \fBtom \s-1AT\s0 vondein \s-1DOT\s0 org\fR
diff --git a/dicepwgen.c b/dicepwgen.c
new file mode 100644
index 0000000..48fc260
--- /dev/null
+++ b/dicepwgen.c
@@ -0,0 +1,146 @@
+/*
+ *    This file is part of dicepwgen
+ *
+ *    Copyright (C) 2015 T.v.Dein.
+ *
+ *    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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *    You can contact me by mail: <tom AT vondein DOT org>.
+ */
+
+#include "dicepwgen.h"
+
+int usage() {
+  fprintf(stderr,
+	  "Generate a random diceware passphrase\n"
+	  "Usage: dice [-tcfvh]\n"
+	  "Options: \n"
+	  "-t --humantoss            Asks interactively for tossed dices\n"
+	  "-c --wordcount <count>    Number of words (default: 4)\n"
+	  "-f --dictfile <dictfile>  Dictionary file to use (default:\n"
+	  "                          /usr/share/dict/american-english)\n"
+	  "-l --minlen <count>       Minimum word len (default: 5)\n"
+	  "-m --maxlen <count>       Maximum word len (default: 10)\n"
+	  "-v --version              Print program version\n"
+	  "-h -? --help              Print this help screen\n"
+	  );
+  return 1;
+}
+
+int main (int argc, char **argv)  {
+  int count = 4;
+  char *dictfile = NULL;
+  unsigned char *tosses = NULL;
+  int opt;
+
+  WMIN = 6;
+  WMAX = 10;
+  humantoss = 0;
+  
+  static struct option longopts[] = {
+    { "wordcount", required_argument, NULL,           'c' },
+    { "minlen",    required_argument, NULL,           'l' },
+    { "maxlen",    required_argument, NULL,           'm' },
+    { "humantoss", required_argument, NULL,           't' },    
+    { "dictfile",  required_argument, NULL,           'f' },
+    { "version",   no_argument,       NULL,           'v' },
+    { "help",      no_argument,       NULL,           'h' },
+  };
+
+   while ((opt = getopt_long(argc, argv, "l:m:tf:c:vh?", longopts, NULL)) != -1) {
+     switch (opt) {
+     case 'v':
+       fprintf(stderr, "This is %s version %s\n", argv[0], VERSION);
+       return 1;
+       break;
+     case 'h':
+     case '?':
+       return usage();
+       break;
+     case 'c':
+       count = atoi(optarg);
+       break;
+     case 'l':
+       WMIN = atoi(optarg);
+       break;
+     case 'm':
+       WMAX = atoi(optarg);
+       break;
+     case 't':
+       humantoss = 1;
+       break;
+     case 'f':
+       dictfile = malloc(strlen(optarg));
+       strncpy(dictfile, optarg, strlen(optarg));
+       break;
+     default:
+      return usage();
+      break;
+     }
+   }
+
+
+   if(dictfile == NULL) {
+     dictfile = DICTFILE;
+   }
+   
+   getwords(dictfile, count);
+
+   return 0;
+}
+
+void getwords(char *dictfile, int count) {
+  /*
+    initiate dice tossing, extract matching number of words
+    froom the wordlist and print it.
+   */
+  char **words;
+  int i, pos, one, two, three, four, five;
+  int *tossed;
+  unsigned char *tosses;
+  
+  words = fetch_dict(dictfile);
+
+  tossed = malloc(count * sizeof(int));
+  
+  for(i=0; i<count; i++) {
+    tosses = toss(5);
+
+    one    = tosses[0] * 10000;
+    two    = tosses[1] *  1000;
+    three  = tosses[2] *   100;
+    four   = tosses[3] *    10;
+    five   = tosses[4];
+    
+    pos = one + two + three + four + five;
+
+    tossed[i] = pos;
+
+    free(tosses);
+  }
+
+  for(i=0; i<count; i++) {
+    fprintf(stdout, "%s ", words[tossed[i]]);
+  }
+
+  fprintf(stdout, "\n");
+  
+  free(tossed);
+
+  for(i=0; i<6666; i++)
+    if(words[i] != NULL)
+      free(words[i]);
+
+  free(words);
+}
diff --git a/dicepwgen.h b/dicepwgen.h
new file mode 100644
index 0000000..44c0f15
--- /dev/null
+++ b/dicepwgen.h
@@ -0,0 +1,48 @@
+/*
+ *    This file is part of dicepwgen
+ *
+ *    Copyright (C) 2015 T.v.Dein.
+ *
+ *    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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *    You can contact me by mail: <tom AT vondein DOT org>.
+ */
+
+#ifndef HAVE_DICE_H
+#define  HAVE_DICE_H
+
+#include <stdio.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <ctype.h>
+
+#include "dictfile.h"
+#include "tossing.h"
+
+#define  DICTFILE "/usr/share/dict/american-english"
+#define  VERSION  "1.0"
+#define  RLEN     1024
+
+int humantoss;
+int WMIN;
+int WMAX;
+
+int usage();
+int main (int argc, char **argv);
+void getwords(char *dictfile, int count);
+
+#endif
diff --git a/dicepwgen.pod b/dicepwgen.pod
new file mode 100644
index 0000000..3bfeb01
--- /dev/null
+++ b/dicepwgen.pod
@@ -0,0 +1,61 @@
+=head1 NAME
+
+dicepwgen - A diceware password generator
+
+=head1 SYNOPSIS
+
+ Usage: dice [-cfvh]
+ Options: 
+ -t --humantoss            Asks interactively for tossed dices
+ -c --wordcount <count>    Number of words (default: 4)
+ -f --dictfile <dictfile>  Dictionary file to use (default:
+                           /usr/share/dict/american-english)
+ -l --minlen <count>       Minimum word len (default: 5)
+ -m --maxlen <count>       Maximum word len (default: 10)
+ -v --version              Print program version
+ -h -? --help              Print this help screen
+
+=head1 DESCRIPTION
+
+dicepwgen generates a diceware password using a dictionary
+file. By default it uses pseudo random dice tosses, but
+it is also possible to use real dices and enter the numbers
+by using the option B<-t>.
+
+The option B<-c> can be used to tweak the number of words
+to output. The options B<-l> and B<-m> can be used to tweak
+minimum and maximum word length.
+
+You can tell dicepwgen to use another dictionary file with
+the option B<-f>.
+
+The program only uses words which contain 7bit ASCII letters
+(a-zA-Z), which are easier for password usage anyway.
+
+=head1 FILES
+
+B</usr/share/dict/american-english>: default dictionary file.
+
+=head1 SEE ALSO
+
+L<http://world.std.com/~reinhold/diceware.html>
+
+L<https://xkcd.com/936/>.
+
+=head1 BUGS
+
+In order to report a bug, unexpected behavior, feature requests
+or to submit a patch, please open an issue on github:
+L<https://github.com/TLINDEN/diceware/issues>.
+
+=head1 LICENSE
+
+This software is licensed under the GNU GENERAL PUBLIC LICENSE version 3.
+
+Copyright (c) 2015 by T. v. Dein.
+
+=head1 AUTHORS
+
+T.v.Dein B<tom AT vondein DOT org>
+
+=cut
diff --git a/dictfile.c b/dictfile.c
new file mode 100644
index 0000000..ac4867c
--- /dev/null
+++ b/dictfile.c
@@ -0,0 +1,139 @@
+/*
+ *    This file is part of dicepwgen
+ *
+ *    Copyright (C) 2015 T.v.Dein.
+ *
+ *    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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *    You can contact me by mail: <tom AT vondein DOT org>.
+ */
+
+#include "dictfile.h"
+
+int *incr_dicedigit(int *digits) {
+  /*
+    increment an array of dice digits, we expect the first to
+    be a multiple of 10000, the 2nd a multiple of 1000 and so on.
+  */
+  if(digits[4] == 6) {
+    digits[4] = 1;
+    if(digits[3] == 60) {
+      digits[3] = 10;
+      if(digits[2] == 600) {
+	digits[2] = 100;
+	if(digits[1] == 6000) {
+	  digits[1] = 1000;
+	  digits[0] += 10000; /* may overflow to 71111, must be catched by caller */
+	}
+	else
+	  digits[1] += 1000;
+      }
+      else
+	digits[2] += 100;
+    }
+    else
+      digits[3] += 10;
+  }
+  else
+    digits[4]++;
+
+  return digits;
+}
+
+char **fetch_dict(char *dictfile) {
+  /*
+    read in the dictionary file. we generate an array of max
+    66666 entries from the dictionary, each entry's index will
+    be a dice number (1 <=> 6). to enhance randomness, we jump
+    over a number of lines (1-32 lines) and start from the beginning
+    of the file if we reach the end before our array is full.
+  */
+
+  char **words;
+  int pos, i, next, jump;
+  char *line = NULL;
+  size_t len = 0;
+  ssize_t linelen;
+  FILE *DICT;
+  int *digits;
+
+  if((DICT = fopen(dictfile, "rb")) == NULL) {
+    perror("Could not open dictfile");
+  }
+
+  words = malloc(66666 * sizeof(char *));
+  digits = malloc(5);
+  jump = rand_lim(32);
+  
+  digits[0] = 10000;
+  digits[1] =  1000;
+  digits[2] =   100;
+  digits[3] =    10;
+  digits[4] =     1;
+
+  pos   = 11111;
+  next = 0;
+
+  for(i=0; i<6666; i++)
+    words[i] = NULL;
+
+  
+ LOOP:
+  while ((linelen = getline(&line, &len, DICT)) != -1) {
+    if(jump > 0) {
+      jump--;
+      continue;
+    }
+    else {
+      jump = rand_lim(32);
+    }
+    if(linelen >= WMIN+1 && linelen <= WMAX+1) {
+      line[linelen-1] = '\0'; /* remove newline */
+
+      for(i=0; i<linelen-1; i++) {
+	if(isalpha((int)line[i]) == 0) {
+	  next = 1;
+	  break;
+	}
+      }
+
+      if(next) {
+	next = 0;
+	continue;
+      }
+      
+      words[pos] = malloc(linelen);
+      strncpy( words[pos], line, linelen);
+      //fprintf(stdout, "%d: %s\n", pos, line);
+      
+      digits = incr_dicedigit(digits);
+      pos = get_dicenum(digits);
+
+      /* this is what pos gets next after 66666, which is max reachable with 5 dices */
+      if(pos == 71111)
+	break;
+    } /* endif word 4<=>10 */
+  } /* while read */
+
+  if(pos < 66666) {
+    fseek(DICT, 0L, SEEK_SET);
+    goto LOOP;
+  }
+  
+  fclose(DICT);
+  free(line);
+  free(digits);
+
+  return words;
+}
diff --git a/dictfile.h b/dictfile.h
new file mode 100644
index 0000000..f564ffe
--- /dev/null
+++ b/dictfile.h
@@ -0,0 +1,40 @@
+/*
+ *    This file is part of dicepwgen
+ *
+ *    Copyright (C) 2015 T.v.Dein.
+ *
+ *    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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *    You can contact me by mail: <tom AT vondein DOT org>.
+ */
+
+#ifndef HAVE_DICTFILE_H
+#define  HAVE_DICTFILE_H
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <ctype.h>
+
+#include "tossing.h"
+
+extern int WMIN;
+extern int WMAX;
+
+int *incr_dicedigit(int *digits);
+char **fetch_dict(char *dictfile);
+
+#endif
diff --git a/tossing.c b/tossing.c
new file mode 100644
index 0000000..7eda714
--- /dev/null
+++ b/tossing.c
@@ -0,0 +1,124 @@
+/*
+ *    This file is part of dicepwgen
+ *
+ *    Copyright (C) 2015 T.v.Dein.
+ *
+ *    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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *    You can contact me by mail: <tom AT vondein DOT org>.
+ */
+
+#include "tossing.h"
+
+unsigned char *toss(int count) {
+  /*
+    toss <count> dices. if the global humandice is enabled (option -t),
+    then ask the human to toss dices and enter the numbers interactively.
+    otherwise generate tosses from /dev/random.
+   */
+  
+  FILE *RAND;
+  int i;
+  int pos = 0;
+  uint8_t onedice;
+  unsigned char *tosses = NULL;
+  unsigned char *rand = NULL;
+  size_t len;
+  ssize_t linelen;
+ 
+  if(humantoss) {
+    char *line = NULL;
+    char digit[2];
+    digit[1] = '\0';
+   
+  RETRY:
+    fprintf(stderr, "enter 5 digits, each between 1-6\n");
+    linelen = getline(&line, &len, stdin);
+    tosses = malloc((size_t)count);
+    
+    if(linelen < 6) /* 5 digits max allowed */
+      goto RETRY;
+
+    for(i=0; i<count; i++) { /* only digits allowed */
+      if(isdigit(line[i]) == 0)
+	goto RETRY;
+
+      digit[0] = line[i];
+      onedice = atoi(digit);
+
+      if (onedice < 1 || onedice > 6) /* no dice digit */
+	goto RETRY;
+
+      tosses[i] = onedice;
+    }
+    free(line);
+  }
+  else {
+    rand = malloc(RLEN);
+ 
+    if((RAND = fopen("/dev/urandom", "rb")) == NULL)
+      perror("Could not open /dev/urandom");
+
+    if(fread(rand, RLEN, 1, RAND) != 1)
+      perror("Could not read from /dev/urandom");
+    
+    fclose(RAND);
+
+    tosses = malloc((size_t)count);
+    
+    for(i=0; i<RLEN; i++) {
+      onedice = rand[i];
+      onedice &= 7; /* only use the last 3 bits, 0-7 */
+      onedice %= 6; /* 6 is the max */
+      if(onedice >= 1 && onedice <= 6) {
+	tosses[pos] = onedice;
+	pos++;
+      }
+      if(pos == count)
+	break;
+    }
+    free(rand);
+  }
+ 
+  return tosses;
+}
+
+int rand_lim(int limit) {
+  /*
+    return a random number in the range [0..limit)
+   */
+
+    int divisor = RAND_MAX/limit;
+    int retval;
+
+    do { 
+        retval = rand() / divisor;
+    } while (retval == limit);
+
+    return retval;
+}
+
+
+
+int get_dicenum(int *digits) {
+  /*
+    get the actual number of an array of dice digits
+  */
+  int i = 0;
+  int pos = 0;
+  for(i=0; i<5; i++)
+    pos += digits[i];
+
+  return pos;
+}
diff --git a/tossing.h b/tossing.h
new file mode 100644
index 0000000..d1a2156
--- /dev/null
+++ b/tossing.h
@@ -0,0 +1,42 @@
+/*
+ *    This file is part of dicepwgen
+ *
+ *    Copyright (C) 2015 T.v.Dein.
+ *
+ *    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 3 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, see <http://www.gnu.org/licenses/>.
+ *
+ *    You can contact me by mail: <tom AT vondein DOT org>.
+ */
+
+#ifndef HAVE_TOSSING_H
+#define  HAVE_TOSSING_H
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <ctype.h>
+
+#define  RLEN     1024
+
+extern int humantoss;
+extern int WMIN;
+extern int WMAX;
+
+unsigned char *toss(int count);
+int rand_lim(int limit);
+int get_dicenum(int *digits);
+
+#endif