Encrypt password with md5 for Shiny-app.

server.R

library(shiny)
library(datasets)
Logged = FALSE;
PASSWORD <- data.frame(Brukernavn = "withr", Passord = "25d55ad283aa400af464c76d713c07ad")
# Define server logic required to summarize and view the selected dataset
shinyServer(function(input, output) {
  source("www/Login.R",  local = TRUE)
  
  observe({
    if (USER$Logged == TRUE) {
      output$obs <- renderUI({
        sliderInput("obs", "Number of observations:", 
                    min = 10000, max = 90000, 
                    value = 50000, step = 10000)
      })
      
      output$distPlot <- renderPlot({
        dist <- NULL
        dist <- rnorm(input$obs)
        hist(dist, breaks = 100, main = paste("Your password:", input$passwd))
      })
    }
  })
})

ui.R

shinyUI(bootstrapPage(
  # Add custom CSS & Javascript;
  tagList(
    tags$head(
      tags$link(rel="stylesheet", type="text/css",href="style.css"),
      tags$script(type="text/javascript", src = "md5.js"),
      tags$script(type="text/javascript", src = "passwdInputBinding.js")
    )
  ),
  
  ## Login module;
  div(class = "login",
      uiOutput("uiLogin"),
      textOutput("pass")
  ), 
  
  div(class = "span4", uiOutput("obs")),
  div(class = "span8", plotOutput("distPlot"))
  
))

www\Login.R

#### Log in module ###
USER <- reactiveValues(Logged = Logged)

passwdInput <- function(inputId, label) {
  tagList(
    tags$label(label),
    tags$input(id = inputId, type="password", value="")
  )
}

output$uiLogin <- renderUI({
  if (USER$Logged == FALSE) {
    wellPanel(
      textInput("userName", "User Name:"),
      passwdInput("passwd", "Pass word:"),
      br(),
      actionButton("Login", "Log in")
    )
  }
})

output$pass <- renderText({  
  if (USER$Logged == FALSE) {
    if (!is.null(input$Login)) {
   if (input$Login > 0) {
      Username <- isolate(input$userName)
      Password <- isolate(input$passwd)
      Id.username <- which(PASSWORD$Brukernavn == Username)
      Id.password <- which(PASSWORD$Passord    == Password)
      if (length(Id.username) > 0 & length(Id.password) > 0) {
        if (Id.username == Id.password) {
          USER$Logged <- TRUE
        } 
      } else  {
        "User name or password failed!"
      }
    } 
    }
  }
})

www\md5.js

// Downloaded from: http://www.myersdaily.org/joseph/javascript/md5.js;

function md5cycle(x, k) {
  var a = x[0], b = x[1], c = x[2], d = x[3];
  
  a = ff(a, b, c, d, k[0], 7, -680876936);
  d = ff(d, a, b, c, k[1], 12, -389564586);
  c = ff(c, d, a, b, k[2], 17,  606105819);
  b = ff(b, c, d, a, k[3], 22, -1044525330);
  a = ff(a, b, c, d, k[4], 7, -176418897);
  d = ff(d, a, b, c, k[5], 12,  1200080426);
  c = ff(c, d, a, b, k[6], 17, -1473231341);
  b = ff(b, c, d, a, k[7], 22, -45705983);
  a = ff(a, b, c, d, k[8], 7,  1770035416);
  d = ff(d, a, b, c, k[9], 12, -1958414417);
  c = ff(c, d, a, b, k[10], 17, -42063);
  b = ff(b, c, d, a, k[11], 22, -1990404162);
  a = ff(a, b, c, d, k[12], 7,  1804603682);
  d = ff(d, a, b, c, k[13], 12, -40341101);
  c = ff(c, d, a, b, k[14], 17, -1502002290);
  b = ff(b, c, d, a, k[15], 22,  1236535329);
  
  a = gg(a, b, c, d, k[1], 5, -165796510);
  d = gg(d, a, b, c, k[6], 9, -1069501632);
  c = gg(c, d, a, b, k[11], 14,  643717713);
  b = gg(b, c, d, a, k[0], 20, -373897302);
  a = gg(a, b, c, d, k[5], 5, -701558691);
  d = gg(d, a, b, c, k[10], 9,  38016083);
  c = gg(c, d, a, b, k[15], 14, -660478335);
  b = gg(b, c, d, a, k[4], 20, -405537848);
  a = gg(a, b, c, d, k[9], 5,  568446438);
  d = gg(d, a, b, c, k[14], 9, -1019803690);
  c = gg(c, d, a, b, k[3], 14, -187363961);
  b = gg(b, c, d, a, k[8], 20,  1163531501);
  a = gg(a, b, c, d, k[13], 5, -1444681467);
  d = gg(d, a, b, c, k[2], 9, -51403784);
  c = gg(c, d, a, b, k[7], 14,  1735328473);
  b = gg(b, c, d, a, k[12], 20, -1926607734);
  
  a = hh(a, b, c, d, k[5], 4, -378558);
  d = hh(d, a, b, c, k[8], 11, -2022574463);
  c = hh(c, d, a, b, k[11], 16,  1839030562);
  b = hh(b, c, d, a, k[14], 23, -35309556);
  a = hh(a, b, c, d, k[1], 4, -1530992060);
  d = hh(d, a, b, c, k[4], 11,  1272893353);
  c = hh(c, d, a, b, k[7], 16, -155497632);
  b = hh(b, c, d, a, k[10], 23, -1094730640);
  a = hh(a, b, c, d, k[13], 4,  681279174);
  d = hh(d, a, b, c, k[0], 11, -358537222);
  c = hh(c, d, a, b, k[3], 16, -722521979);
  b = hh(b, c, d, a, k[6], 23,  76029189);
  a = hh(a, b, c, d, k[9], 4, -640364487);
  d = hh(d, a, b, c, k[12], 11, -421815835);
  c = hh(c, d, a, b, k[15], 16,  530742520);
  b = hh(b, c, d, a, k[2], 23, -995338651);
  
  a = ii(a, b, c, d, k[0], 6, -198630844);
  d = ii(d, a, b, c, k[7], 10,  1126891415);
  c = ii(c, d, a, b, k[14], 15, -1416354905);
  b = ii(b, c, d, a, k[5], 21, -57434055);
  a = ii(a, b, c, d, k[12], 6,  1700485571);
  d = ii(d, a, b, c, k[3], 10, -1894986606);
  c = ii(c, d, a, b, k[10], 15, -1051523);
  b = ii(b, c, d, a, k[1], 21, -2054922799);
  a = ii(a, b, c, d, k[8], 6,  1873313359);
  d = ii(d, a, b, c, k[15], 10, -30611744);
  c = ii(c, d, a, b, k[6], 15, -1560198380);
  b = ii(b, c, d, a, k[13], 21,  1309151649);
  a = ii(a, b, c, d, k[4], 6, -145523070);
  d = ii(d, a, b, c, k[11], 10, -1120210379);
  c = ii(c, d, a, b, k[2], 15,  718787259);
  b = ii(b, c, d, a, k[9], 21, -343485551);
  
  x[0] = add32(a, x[0]);
  x[1] = add32(b, x[1]);
  x[2] = add32(c, x[2]);
  x[3] = add32(d, x[3]);
  
}

function cmn(q, a, b, x, s, t) {
  a = add32(add32(a, q), add32(x, t));
  return add32((a << s) | (a >>> (32 - s)), b);
}

function ff(a, b, c, d, x, s, t) {
  return cmn((b & c) | ((~b) & d), a, b, x, s, t);
}

function gg(a, b, c, d, x, s, t) {
  return cmn((b & d) | (c & (~d)), a, b, x, s, t);
}

function hh(a, b, c, d, x, s, t) {
  return cmn(b ^ c ^ d, a, b, x, s, t);
}

function ii(a, b, c, d, x, s, t) {
  return cmn(c ^ (b | (~d)), a, b, x, s, t);
}

function md51(s) {
  txt = '';
  var n = s.length,
  state = [1732584193, -271733879, -1732584194, 271733878], i;
  for (i=64; i<=s.length; i+=64) {
    md5cycle(state, md5blk(s.substring(i-64, i)));
  }
  s = s.substring(i-64);
  var tail = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
  for (i=0; i<s.length; i++)
    tail[i>>2] |= s.charCodeAt(i) << ((i%4) << 3);
  tail[i>>2] |= 0x80 << ((i%4) << 3);
  if (i > 55) {
    md5cycle(state, tail);
    for (i=0; i<16; i++) tail[i] = 0;
  }
  tail[14] = n*8;
  md5cycle(state, tail);
  return state;
}

function md5blk(s) { /* I figured global was faster.   */
  var md5blks = [], i; /* Andy King said do it this way. */
  for (i=0; i<64; i+=4) {
    md5blks[i>>2] = s.charCodeAt(i)
    + (s.charCodeAt(i+1) << 8)
    + (s.charCodeAt(i+2) << 16)
    + (s.charCodeAt(i+3) << 24);
  }
  return md5blks;
}

var hex_chr = '0123456789abcdef'.split('');

function rhex(n)
{
  var s='', j=0;
  for(; j<4; j++)
    s += hex_chr[(n >> (j * 8 + 4)) & 0x0F]
  + hex_chr[(n >> (j * 8)) & 0x0F];
  return s;
}

function hex(x) {
  for (var i=0; i<x.length; i++)
    x[i] = rhex(x[i]);
  return x.join('');
}

function md5(s) {
  return hex(md51(s));
}

function add32(a, b) {
  return (a + b) & 0xFFFFFFFF;
}

if (md5('hello') != '5d41402abc4b2a76b9719d911017c592') {
  function add32(x, y) {
    var lsw = (x & 0xFFFF) + (y & 0xFFFF),
    msw = (x >> 16) + (y >> 16) + (lsw >> 16);
    return (msw << 16) | (lsw & 0xFFFF);
  }
}

www\passwdInputBinding.js

jQuery(function($) {
  // Password Input
  var passwordInputBinding = new Shiny.InputBinding();
  $.extend(passwordInputBinding, {
    find: function(scope) {
      return $(scope).find('input[type="password"]');
    },
    getId: function(el) {
      return Shiny.InputBinding.prototype.getId.call(this, el) || el.name;
    },
    getValue: function(el) {
      return md5(el.value);
    },
    setValue: function(el, value) {
      el.value = value;
    },
    subscribe: function(el, callback) {
      $(el).on('keyup.passwordInputBinding input.passwordInputBinding', function(event) {
        callback(true);
      });
      $(el).on('change.passwordInputBinding', function(event) {
        callback(false);
      });
    },
    unsubscribe: function(el) {
      $(el).off('.passwordInputBinding');
    },
    getRatePolicy: function() {
      return {
        policy: 'debounce',
        delay: 250
      };
    }
  });
  Shiny.inputBindings.register(passwordInputBinding, 'shiny.passwordInput');
})

www\style.css

div.login { 
  text-align: left;
  position:absolute;
  top: 40%;
  left: 50%;
  margin-top: -100px;
  margin-left: -150px;
} 

div#pass {
  text-align: left;
  font-weight:bold;
  padding-left:2px;
}

input#Password {
  -webkit-text-security: disc;
}

body {
  margin:1cm;
  font-size: 12px;
}

.shiny-output-error {
  visibility: hidden;
}

We can use MD5 hash generator:

http://passwordsgenerators.net/md5-hash-generator