annotate mod_openid/README.markdown @ 1810:2905137cf541

mod_s2s_log_certs/README: Fix link
author Kim Alvefur <zash@zash.se>
date Mon, 31 Aug 2015 17:30:10 +0200
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1 ---
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2 labels:
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3 - 'Stage-Alpha'
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4 summary: Enables Prosody to act as an OpenID provider
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5 ...
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6
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7 Introduction
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8 ============
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9
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10 [OpenID](http://openid.net/) is an decentralized authentication
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11 mechanism for the Web. mod\_openid turns Prosody into an OpenID
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12 *provider*, allowing users to use their Prosody credentials to
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13 authenticate with various third party websites.
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14
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15 Caveats
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16 =======
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17
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18 mod\_openid can best be described as a **proof-of-concept**, it has
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19 known deficiencies and should **not** be used in the wild as a
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20 legitimate OpenID provider. mod\_openid was developed using the Prosody
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21 0.4.x series, it has not been tested with the 0.5.x or later series.
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22
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23 Details
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24 =======
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25
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26 OpenID works on the basis of a user proving to a third-party they wish
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27 to authenticate with, an OpenID *relaying party*, that they have claim
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28 or ownership over a URL, known as an OpenID *identifier*. mod\_openid
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29 uses Prosody's built in HTTP server to provide every user with an OpenID
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30 identifier of the form `http://host.domain.tld[:port]/openid/user`,
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31 which would be the OpenID identifier of the user with a Jabber ID of
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32 `user@host.domain.tld`.
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33
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34 Usage
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35 =====
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36
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37 Simply add "mod\_openid" to your modules\_enabled list. You may then use
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38 the OpenID identifier form as described above as your OpenID identifier.
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39 The port Prosody's HTTP server will listen on is currently set as 5280,
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40 meaning the full OpenID identifier of the user `romeo@montague.lit`
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41 would be `http://montague.lit:5280/openid/romeo`.
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42
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43 Configuration
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44 =============
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45
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46 mod\_openid has no configuration options as of this time.
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47
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48 TODO
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49 ====
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50
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51 The following is a list of the pending tasks which would have to be done
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52 to make mod\_openid fully featured. They are generally ranked in order
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53 of most importance with an estimated degree of difficulty.
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54
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55 1. Support Prosody 0.6.x series
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56 (<font color='blue'><i>Medium</i></font>)
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57 2. Refactor code (<font color='blue'><i>Medium</i></font>)
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58 - The code is pretty messy at the moment, it should be refactored
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59 to be more easily understood.
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60
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61 3. Disable use of "user@domain" OpenID identifier form
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62 (<font color='green'><i>Easy</i></font>)
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63 - This is a vestigial feature from the early design, allowing
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64 explicit specification of the JID. However the JID can be
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65 inferred from the simpler OpenID identifier form.
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66
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67 4. Use a cryptographically secure Pseudo Random Number Generator (PRNG)
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68 (<font color='blue'><i>Medium</i></font>)
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69 - This would likely be accomplished using luacrypto which provides
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70 a Lua binding to the OpenSSL PRNG.
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71
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72 5. Make sure OpenID key-value pairs get signed in the right order
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73 (<font color='red'><i>Hard</i></font>)
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74 - It is important that the OpenID key-value responses be signed in
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75 the proper order so that the signature can be properly verified
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76 by the receiving party. This may be complicated by the fact that
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77 the iterative ordering of keys in a Lua table is not guaranteed
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78 for non-integer keys.
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79
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80 6. Do an actual match on the OpenID realm
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81 (<font color='blue'><i>Medium</i></font>)
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82 - The code currently always returns true for matches against an
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83 OpenID realm, posing a security risk.
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84
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85 7. Don't use plain text authentication over HTTP
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86 (<font color='red'><i>Hard</i></font>)
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87 - This would require some Javascript to perform a digest.
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88
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89 8. Return meaningful error responses
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90 (<font color='blue'><i>Medium</i></font>)
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91 - Most error responses are an HTTP 404 File Not Found, obviously
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92 something more meaningful could be returned.
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93
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94 9. Enable Association (<font color='red'><i>Hard</i></font>)
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95 - Association is a feature of the OpenID specification which
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96 reduces the number of round-trips needed to perform
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97 authentication.
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98
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99 10. Support HTTPS (<font color='blue'><i>Medium</i></font>)
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100 - With option to only allow authentication through HTTPS
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101
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102 11. Enable OpenID 1.1 compatibility
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103 (<font color='blue'><i>Medium</i></font>)
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104 - mod\_openid is designed from the OpenID 2.0 specification, which
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105 has an OpenID 1.1 compatibility mode.
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106
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107 12. Check specification compliance
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108 (<font color='blue'><i>Medium</i></font>)
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109 - Walk through the code and make sure it complies with the OpenID
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110 specification. Comment code as necessary with the relevant
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111 sections in the specification.
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112
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113 Once all these steps are done, mod\_openid could be considered to have
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114 reached "beta" status and ready to real world use. The following are
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115 features that would be nice to have in a stable release:
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116
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117 1. Allow users to always trust realms
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118 (<font color='red'><i>Hard</i></font>)
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119 2. Allow users to remain logged in with a cookie
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120 (<font color='red'><i>Hard</i></font>)
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121 3. Enable simple registration using a user's vCard
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122 (<font color='blue'><i>Medium</i></font>)
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123 4. More useful user identity page
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124 (<font color='red'><i>Hard</i></font>)
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125 - Allow users to alter what realms they trust and what simple
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126 registration information gets sent to relaying parties by
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127 default.
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128
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129 5. OpenID Bot (<font color='red'><i>Hard</i></font>)
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130 - Offers all functionality of the user identity page management
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131
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132 6. Better designed pages (<font color='green'>Easy</font>)
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133 - Use semantic XHTML and CSS to allow for custom styling.
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134 - Use the Prosody favicon.
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135
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136 Useful Links
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137 ============
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138
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139 - [OpenID Specifications](http://openid.net/developers/specs/)
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140 - [OpenID on Wikipedia](http://en.wikipedia.org/wiki/OpenID)