├── templates
    ├── error.html
    ├── feedset.html
    ├── list.html
    ├── nopwresetrequest.html
    ├── nosignup.html
    ├── error_login.html
    ├── account.html
    ├── info.html
    ├── pwreset.html
    ├── index.html
    ├── accountsetmail.html
    ├── pwresetquestion.html
    ├── accountsetpw.html
    ├── partials.html
    ├── accountsetquestion.html
    ├── style.css
    ├── pwresetrequest.html
    └── signupform.html
├── io.go
├── README.md
├── main.go
├── handlers.go
└── LICENSE


/templates/error.html:
--------------------------------------------------------------------------------
1 | {{ template "header" }}
2 | 	<section class="error">
3 | 		<h2>Error</h2>
4 | 		<p>Something went wrong: {{ .Msg }}</p>
5 | 	</section>
6 | {{ template "footer" }}
7 | 


--------------------------------------------------------------------------------
/templates/feedset.html:
--------------------------------------------------------------------------------
1 | {{ template "header" }}
2 | 	<section class="success">
3 | 		<h2>Success</h2>
4 | 		<p>Your account has been set up.</p>
5 | 	</section>
6 | {{ template "footer" }}
7 | 


--------------------------------------------------------------------------------
/templates/list.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <section>
 3 | 	<h2>Feeds</h2>
 4 | 	<ul>
 5 | 	{{ range .Dir }}
 6 | 		<li><a href="/feeds/{{ . }}">{{ . }}</a></li>
 7 | 	{{ end }}
 8 | 	</ul>
 9 | </section>
10 | {{ template "footer" }}
11 | 


--------------------------------------------------------------------------------
/templates/nopwresetrequest.html:
--------------------------------------------------------------------------------
1 | {{ template "header" }}
2 | <section>
3 | 	<h2>Password reset inactive</h2>
4 | 	<p>The site operator has currently not activated automatic password resetting.</p>
5 | </section>
6 | {{ template "footer" }}
7 | 
8 | 


--------------------------------------------------------------------------------
/templates/nosignup.html:
--------------------------------------------------------------------------------
1 | {{ template "header" }}
2 | <section>
3 | 	<h2>Account creation closed</h2>
4 | 	<p>The site operator has not decided to currently open up account creation on this site to the public.</p>
5 | </section>
6 | {{ template "footer" }}
7 | 


--------------------------------------------------------------------------------
/templates/error_login.html:
--------------------------------------------------------------------------------
1 | {{ template "header" }}
2 | 	<section class="error">
3 | 		<h2>Error</h2>
4 | 		<p>Something went wrong: Bad login. (Have you forgotten your password? If you added a mail address to your login data, you might be able to <a href="/passwordreset">reset</a> it.)</p>
5 | 	</section>
6 | {{ template "footer" }}
7 | 
8 | 


--------------------------------------------------------------------------------
/templates/account.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <section>
 3 | 	<h2>Account settings</h2>
 4 | 	<ul>
 5 | 		<li><a href="/accountsetpw">Change password</a></li>
 6 | 		<li><a href="/accountsetmail">Set mail address</a></li>
 7 | 		<li><a href="/accountsetquestion">Set security question</a></li>
 8 | 		<li><a href="/passwordreset">Request password reset</a></li>
 9 | 	</ul>
10 | </section>
11 | {{ template "footer" }}
12 | 


--------------------------------------------------------------------------------
/templates/info.html:
--------------------------------------------------------------------------------
1 | {{ template "header" }}
2 | <section>
3 | 	<h2>About this site</h2>
4 | 	<p>This site is a web server to host and grow <a href="https://github.com/buckket/twtxt">twtxt</a> feeds for users without trivial access to their own web space.</p>
5 | 	<p>Its operator gives no guarantees regarding long-term availability of feeds, stability of their paths, or quality and integrity of their contents. If that does not satisfy your needs, consider hosting your own instance: The underlying server software <a href="https://github.com/plomlompom/htwtxt">htwtxt</a> is freely available, and should not be too difficult to set up.</p>
6 | 	<p>Site operator's contact info: {{ .Msg }}</p>
7 | </section>
8 | {{ template "footer" }}
9 | 


--------------------------------------------------------------------------------
/templates/pwreset.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="/passwordreset/{{ .Msg }}">
 3 | 	<fieldset>
 4 | 		<legend>Reset account data</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="name">Name</label>
 8 | 			<input type="text" id="name" name="name" required />
 9 | 			<p id="name-desc">Please repeat for verification.</p>
10 | 		</div>
11 | 
12 | 		<div>
13 | 			<label for="password">New password</label>
14 | 			<input type="password" id="password" name="new_password" required />
15 | 		</div>
16 | 
17 | 		<div>
18 | 			<label for="password2">New password <span>(repeat)</span></label>
19 | 			<input type="password" id="password2" name="new_password2" required />
20 | 		</div>
21 | 
22 | 		<hr />
23 | 
24 | 		<button type="submit">Reset</button>
25 | 	</fieldset>
26 | </form>
27 | {{ template "footer" }}
28 | 


--------------------------------------------------------------------------------
/templates/index.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="feeds">
 3 | 	<fieldset>
 4 | 		<legend>Send twtxt</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="twt">Message</label>
 8 | 			<input type="text" id="twt" name="twt" maxlength="140" placeholder="What’s happening?" aria-describedby="txt-desc" required />
 9 | 			<p id="txt-desc"><abbr title="Maximum">Max.</abbr> 140 characters</p>
10 | 		</div>
11 | 
12 | 		<div>
13 | 			<label for="name">Name</label>
14 | 			<input type="text" id="name" name="name" required />
15 | 		</div>
16 | 		
17 | 		<div>
18 | 			<label for="password">Password</label>
19 | 			<input type="password" id="password" name="password" required />
20 | 		</div>
21 | 
22 | 		<hr />
23 | 
24 | 		<button type="submit">Publish</button>
25 | 	</fieldset>
26 | </form>
27 | {{ template "footer" }}
28 | 


--------------------------------------------------------------------------------
/templates/accountsetmail.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="accountsetmail">
 3 | 	<fieldset>
 4 | 		<legend>Set account mail address</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="mail">New e-mail address</label>
 8 | 			<input type="email" id="mail" name="mail" aria-describedby="mail-desc" required/>
 9 | 			<p id="mail-desc">Used for password reset and feed owner authentication.</p>
10 | 		</div>
11 | 
12 | 		<hr />
13 | 
14 | 		<div>
15 | 			<label for="name">Name</label>
16 | 			<input type="text" id="name" name="name" maxlength="140" required />
17 | 		</div>
18 | 
19 | 		<div>
20 | 			<label for="password">Password</label>
21 | 			<input type="password" id="password" name="password" required />
22 | 		</div>
23 | 
24 | 		<hr />
25 | 
26 | 		<button type="submit">Update</button>
27 | 	</fieldset>
28 | </form>
29 | {{ template "footer" }}
30 | 


--------------------------------------------------------------------------------
/templates/pwresetquestion.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="/passwordreset/{{ .Secret }}">
 3 | 	<fieldset>
 4 | 		<legend>Reset account data</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="name">Name</label>
 8 | 			<input type="text" id="name" name="name" required />
 9 | 		</div>
10 | 
11 | 		<div>
12 | 			<label for="secanswer">Security question: {{ .Question }}</label>
13 | 			<input type="text" id="secanswer" name="secanswer" required />
14 | 		</div>
15 | 
16 | 		<div>
17 | 			<label for="password">New password</label>
18 | 			<input type="password" id="password" name="new_password" required />
19 | 		</div>
20 | 
21 | 		<div>
22 | 			<label for="password2">New password <span>(repeat)</span></label>
23 | 			<input type="password" id="password2" name="new_password2" required />
24 | 		</div>
25 | 
26 | 		<hr />
27 | 
28 | 		<button type="submit">Reset</button>
29 | 	</fieldset>
30 | </form>
31 | {{ template "footer" }}
32 | 


--------------------------------------------------------------------------------
/templates/accountsetpw.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="accountsetpw">
 3 | 	<fieldset>
 4 | 		<legend>Change account password</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="password">New password</label>
 8 | 			<input type="password" id="password" name="new_password" required />
 9 | 		</div>
10 | 
11 | 		<div>
12 | 			<label for="password2">New password <span>(repeat)</span></label>
13 | 			<input type="password" id="password2" name="new_password2" required />
14 | 		</div>
15 | 
16 | 		<hr />
17 | 
18 | 		<div>
19 | 			<label for="name">Name</label>
20 | 			<input type="text" id="name" name="name" maxlength="140" required />
21 | 		</div>
22 | 
23 | 		<div>
24 | 			<label for="password-old">Current password</label>
25 | 			<input type="password" id="password-old" name="password" required />
26 | 		</div>
27 | 
28 | 		<hr />
29 | 
30 | 		<button type="submit">Update</button>
31 | 	</fieldset>
32 | </form>
33 | {{ template "footer" }}
34 | 


--------------------------------------------------------------------------------
/templates/partials.html:
--------------------------------------------------------------------------------
 1 | {{ define "header" }}
 2 | <!DOCTYPE html>
 3 | <html lang="en">
 4 | 
 5 | <head>
 6 | 
 7 | 	<meta charset="utf-8" />
 8 | 	<meta name="viewport" content="width=device-width, initial-scale=1.0" />
 9 | 
10 | 	<title>hosted twtxt server</title>
11 | 
12 | 	<link rel="stylesheet" type="text/css" href="/style.css" media="all" />
13 | 
14 | </head>
15 | 
16 | <body>
17 | 
18 | 	<header>
19 | 		<h1><a href="/">hosted twtxt server</a></h1>
20 | 	</header>
21 | 
22 | 	<nav>
23 | 		<ul>
24 | 			<li><a href="/feeds">Feeds</a></li>
25 | 			<li><a href="/signup">Create account</a></li>
26 | 			<li><a href="/account">Edit account</a></li>
27 | 		</ul>
28 | 	</nav>
29 | {{ end }}
30 | {{ define "footer" }}
31 | 	<footer>
32 | 		<p>Read more <a href="/info">about this site</a>.<br /> Licensed under <a href="http://www.gnu.org/licenses/agpl-3.0.html" rel="license">AGPLv3</a>. Source code <a href="https://github.com/plomlompom/htwtxt">on GitHub</a>.</p>
33 | 	</footer>
34 | 
35 | </body>
36 | 
37 | </html>
38 | {{ end }}
39 | 


--------------------------------------------------------------------------------
/templates/accountsetquestion.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="accountsetquestion">
 3 | 	<fieldset>
 4 | 		<legend>Set account security question</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="secquestion">New security question</label>
 8 | 			<input type="text" id="secquestion" name="secquestion" aria-describedby="secquestion-desc-desc" required />
 9 | 			<p id="secquestion-desc">To pose on password reset request.</p>
10 | 		</div>
11 | 		
12 | 		<div>
13 | 			<label for="secanswer">New security question answer</label>
14 | 			<input type="text" id="secanswer" name="secanswer" required />
15 | 		</div>
16 | 
17 | 		<hr />
18 | 
19 | 		<div>
20 | 			<label for="name">Name</label>
21 | 			<input type="text" id="name" name="name" maxlength="140" required />
22 | 		</div>
23 | 
24 | 		<div>
25 | 			<label for="password">Password</label>
26 | 			<input type="password" id="password" name="password" required />
27 | 		</div>
28 | 
29 | 		<hr />
30 | 
31 | 		<button type="submit">Update</button>
32 | 	</fieldset>
33 | </form>
34 | {{ template "footer" }}
35 | 


--------------------------------------------------------------------------------
/templates/style.css:
--------------------------------------------------------------------------------
 1 | body {
 2 | 	background-color: white;
 3 | 	color: black;
 4 | 	font: 1rem/1.5 -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Open Sans', 'Helvetica Neue', sans-serif;
 5 | 	word-wrap: break-word;
 6 | 	max-width: 30rem;
 7 | 	padding: 0 1rem;
 8 | 	margin: 0 auto;	
 9 | }
10 | 
11 | a {
12 | 	color: #00c;
13 | }
14 | 
15 | a:hover {
16 | 	background-color: #00c;
17 | 	color: white;
18 | }
19 | 
20 | a:focus {
21 | 	outline: thin solid;
22 | }
23 | 
24 | header,
25 | nav,
26 | footer {
27 | 	text-align: center;
28 | }
29 | 
30 | nav ul {
31 | 	list-style: none;
32 | 	padding-left: 0;
33 | }
34 | 
35 | nav li {
36 | 	display: inline-block;
37 | 	margin: 0 .5rem;
38 | }
39 | 
40 | section,
41 | fieldset {
42 | 	background-color: #eee;
43 | 	padding: 1rem;
44 | 	border: 1px solid black;
45 | }
46 | 
47 | section.success {
48 | 	background-color: #cfc;
49 | }
50 | 
51 | section.error {
52 | 	background-color: #fcc;
53 | }
54 | 
55 | section h2:first-child {
56 | 	margin-top: 0;
57 | }
58 | 
59 | form div {
60 | 	margin-bottom: 1rem;
61 | }
62 | 
63 | form p,
64 | label span {
65 | 	color: #444;
66 | 	font-size: .8rem;
67 | }
68 | 
69 | form p {
70 | 	margin: 0;
71 | }
72 | 
73 | legend,
74 | label {
75 | 	font-weight: bold;
76 | }
77 | 
78 | label {
79 | 	display: block;
80 | }
81 | 
82 | button,
83 | input {
84 | 	font-size: 1rem;
85 | }
86 | 
87 | input#twt {
88 | 	width: 100%;
89 | }
90 | 


--------------------------------------------------------------------------------
/templates/pwresetrequest.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="passwordreset">
 3 | 	<fieldset>
 4 | 		<legend>Request password reset</legend>
 5 | 
 6 | 		<p>To reset the password for an account, an e-mail address <a href="/accountsetmail">must have been set</a> for it. The request here will (if not hindered by the wait time described below) then be answered with an e-mail to the address which contains nothing but a randomized URL pointing back to a page on this server.</p>
 7 | 		<p>Said page will only be available for about 30 minutes. It will ask for the account name, a new password (must be entered twice), and, if a security question <a href="/accountsetquestion">has been set</a> for the account in question, an answer to that. The new password will only be set when the account name given there is the same given here, and, if a security question was set for that account, the answer is the one previously defined for it. Wrong answers will remove the temporary account reset page at once. A new one can be requested here only once every 24 hours.</p>
 8 | 		<p>Note that clicking the button below will always redirect you to this site's start page – no matter whether the server actually sends out a password reset link for any account or not.</p>
 9 | 
10 | 		<div>
11 | 			<label for="name">Name</label>
12 | 			<input type="text" id="name" name="name" />
13 | 		</div>
14 | 
15 | 		<hr />
16 | 
17 | 		<button type="submit">Request reset</button>
18 | 	</fieldset>
19 | </form>
20 | {{ template "footer" }}
21 | 
22 | 


--------------------------------------------------------------------------------
/templates/signupform.html:
--------------------------------------------------------------------------------
 1 | {{ template "header" }}
 2 | <form method="post" action="signup">
 3 | 	<fieldset>
 4 | 		<legend>Create account</legend>
 5 | 
 6 | 		<div>
 7 | 			<label for="name">Name</label>
 8 | 			<input type="text" id="name" name="name" maxlength="140" aria-describedby="name-desc" pattern="[a-zA-Z0-9_]{1,140}" required />
 9 | 			<p id="name-desc">Legal characters: A-Z, a-z, 0-9, _ (<abbr title="maximum">max.</abbr> 140)</p>
10 | 		</div>
11 | 
12 | 		<div>
13 | 			<label for="mail">E-mail address <span>(optional)</span></label>
14 | 			<input type="email" id="mail" name="mail" aria-describedby="mail-desc"/>
15 | 			<p id="mail-desc">Used for password reset and feed owner authentication.</p>
16 | 		</div>
17 | 
18 | 		<div>
19 | 			<label for="secquestion">Security question <span>(optional)</span></label>
20 | 			<input type="text" id="secquestion" name="secquestion" aria-describedby="secquestion-desc" />
21 | 			<p id="secquestion-desc">To pose on password reset request.</p>
22 | 		</div>
23 | 		
24 | 		<div>
25 | 			<label for="secanswer">Security question answer <span>(optional)</span></label>
26 | 			<input type="text" id="secanswer" name="secanswer" />
27 | 		</div>
28 | 
29 | 		<div>
30 | 			<label for="password">Password</label>
31 | 			<input type="password" id="password" name="new_password" required />
32 | 		</div>
33 | 
34 | 		<div>
35 | 			<label for="password2">Password <span>(repeat)</span></label>
36 | 			<input type="password" id="password2" name="new_password2" required />
37 | 		</div>
38 | 
39 | 		<hr />
40 | 		
41 | 		<button type="submit">Sign up</button>
42 | 	</fieldset>
43 | </form>
44 | {{ template "footer" }}
45 | 


--------------------------------------------------------------------------------
/io.go:
--------------------------------------------------------------------------------
  1 | // htwtxt – hosted twtxt server; see README for copyright and license info
  2 | 
  3 | package main
  4 | 
  5 | import "bufio"
  6 | import "errors"
  7 | import "log"
  8 | import "os"
  9 | import "strings"
 10 | import "io/ioutil"
 11 | 
 12 | const loginsFile = "logins.txt"
 13 | const feedsDir = "feeds"
 14 | const ipDelaysFile = "ip_delays.txt"
 15 | const pwResetFile = "password_reset.txt"
 16 | const pwResetWaitFile = "password_reset_wait.txt"
 17 | 
 18 | var certPath string
 19 | var dataDir string
 20 | var feedsPath string
 21 | var ipDelaysPath string
 22 | var keyPath string
 23 | var loginsPath string
 24 | var pwResetPath string
 25 | var pwResetWaitPath string
 26 | var templPath string
 27 | 
 28 | func createFileIfNotExists(path string) {
 29 | 	if _, err := os.Stat(path); err != nil {
 30 | 		file, err := os.Create(path)
 31 | 		if err != nil {
 32 | 			log.Fatal("Can't create file: ", err)
 33 | 		}
 34 | 		file.Close()
 35 | 	}
 36 | }
 37 | 
 38 | func openFile(path string) *os.File {
 39 | 	file, err := os.Open(path)
 40 | 	if err != nil {
 41 | 		file.Close()
 42 | 		log.Fatal("Can't open file for reading", err)
 43 | 	}
 44 | 	return file
 45 | }
 46 | 
 47 | func linesFromFile(path string) []string {
 48 | 	text, err := ioutil.ReadFile(path)
 49 | 	if err != nil {
 50 | 		log.Fatal("Can't read file", err)
 51 | 	}
 52 | 	if string(text) == "" {
 53 | 		return []string{}
 54 | 	}
 55 | 	return strings.Split(string(text), "\n")
 56 | }
 57 | 
 58 | func writeAtomic(path, text string) {
 59 | 	tmpFile := path + "_tmp"
 60 | 	if err := ioutil.WriteFile(tmpFile, []byte(text), 0600); err != nil {
 61 | 		log.Fatal("Trouble writing file", err)
 62 | 	}
 63 | 	if err := os.Rename(path, path+"_"); err != nil {
 64 | 		log.Fatal("Trouble moving file", err)
 65 | 	}
 66 | 	if err := os.Rename(tmpFile, path); err != nil {
 67 | 		log.Fatal("Trouble moving file", err)
 68 | 	}
 69 | 	if err := os.Remove(path + "_"); err != nil {
 70 | 		log.Fatal("Trouble removing file", err)
 71 | 	}
 72 | }
 73 | 
 74 | func writeLinesAtomic(path string, lines []string) {
 75 | 	writeAtomic(path, strings.Join(lines, "\n"))
 76 | }
 77 | 
 78 | func appendToFile(path string, msg string) {
 79 | 	text, err := ioutil.ReadFile(path)
 80 | 	if err != nil {
 81 | 		log.Fatal("Can't read file", err)
 82 | 	}
 83 | 	writeAtomic(path, string(text)+msg+"\n")
 84 | }
 85 | 
 86 | func removeLineStartingWith(path, token string) {
 87 | 	lines := linesFromFile(path)
 88 | 	lineNumber := -1
 89 | 	for lineCount := 0; lineCount < len(lines); lineCount += 1 {
 90 | 		line := lines[lineCount]
 91 | 		tokens := strings.Split(line, "\t")
 92 | 		if 0 == strings.Compare(token, tokens[0]) {
 93 | 			lineNumber = lineCount
 94 | 			break
 95 | 		}
 96 | 	}
 97 | 	lines = append(lines[:lineNumber], lines[lineNumber+1:]...)
 98 | 	writeLinesAtomic(path, lines)
 99 | }
100 | 
101 | func removeLineFromFile(path string, lineNumber int) {
102 | 	lines := linesFromFile(ipDelaysPath)
103 | 	lines = append(lines[:lineNumber], lines[lineNumber+1:]...)
104 | 	writeLinesAtomic(path, lines)
105 | }
106 | 
107 | func replaceLineStartingWith(path, token, newLine string) {
108 | 	lines := linesFromFile(path)
109 | 	for i, line := range lines {
110 | 		tokens := strings.Split(line, "\t")
111 | 		if 0 == strings.Compare(token, tokens[0]) {
112 | 			lines[i] = newLine
113 | 			break
114 | 		}
115 | 	}
116 | 	writeLinesAtomic(path, lines)
117 | }
118 | 
119 | func tokensFromLine(scanner *bufio.Scanner, nTokensExpected int) []string {
120 | 	if !scanner.Scan() {
121 | 		return []string{}
122 | 	}
123 | 	line := scanner.Text()
124 | 	tokens := strings.Split(line, "\t")
125 | 	if len(tokens) != nTokensExpected {
126 | 		log.Fatal("Line in file had unexpected number of tokens")
127 | 	}
128 | 	return tokens
129 | }
130 | 
131 | func getFromFileEntryFor(path, token string,
132 | 	numberTokensExpected int) ([]string, error) {
133 | 	file := openFile(path)
134 | 	defer file.Close()
135 | 	scanner := bufio.NewScanner(bufio.NewReader(file))
136 | 	tokens := tokensFromLine(scanner, numberTokensExpected)
137 | 	for 0 != len(tokens) {
138 | 		if 0 == strings.Compare(tokens[0], token) {
139 | 			return tokens[1:], nil
140 | 		}
141 | 		tokens = tokensFromLine(scanner, numberTokensExpected)
142 | 	}
143 | 	return []string{}, errors.New("")
144 | }
145 | 
146 | func initFilesAndDirs() {
147 | 	log.Println("Using as templates dir:", templPath)
148 | 	log.Println("Using as data dir:", dataDir)
149 | 	loginsPath = dataDir + "/" + loginsFile
150 | 	feedsPath = dataDir + "/" + feedsDir
151 | 	ipDelaysPath = dataDir + "/" + ipDelaysFile
152 | 	pwResetPath = dataDir + "/" + pwResetFile
153 | 	pwResetWaitPath = dataDir + "/" + pwResetWaitFile
154 | 	if "" != keyPath {
155 | 		log.Println("Using TLS.")
156 | 		if _, err := os.Stat(certPath); err != nil {
157 | 			log.Fatal("No certificate file found.")
158 | 		}
159 | 		if _, err := os.Stat(keyPath); err != nil {
160 | 			log.Fatal("No server key file found.")
161 | 		}
162 | 	}
163 | 	createFileIfNotExists(loginsPath)
164 | 	createFileIfNotExists(pwResetPath)
165 | 	createFileIfNotExists(pwResetWaitPath)
166 | 	createFileIfNotExists(ipDelaysPath)
167 | 	// TODO: Handle err here.
168 | 	_ = os.Mkdir(feedsPath, 0700)
169 | }
170 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
  1 | # htwtxt – hosted twtxt server
  2 | 
  3 | ## Rationale
  4 | 
  5 | [*twtxt*](https://github.com/buckket/twtxt) is a protocol and client for
  6 | decentralized microblogging. Users are expected to provide their feeds as plain
  7 | text files with URLs accessible over the Internet. *htwtxt* is a web server to
  8 | host and grow such text files for users without trivial access to their own web
  9 | space.
 10 | 
 11 | ## Features
 12 | 
 13 | - individual twtxt feeds mapped to user accounts with password-protected write
 14 |   access
 15 | - no sessions, no cookies: few POST-writable resources (feeds, account data)
 16 |   expect credentials, which to store between requests if desired is up to the
 17 |   user / browser
 18 | - twtxt messages can be written via a HTML form in a web browser or via an API
 19 | - account registration may be open to the public, or (default) closed (with the
 20 |   site operator adding new accounts manually)
 21 | - users may add e-mail addresses and optional security questions to their
 22 |   accounts to use for a password reset mechanism (if enabled by site operator)
 23 | - HTTPS / TLS support (if paths to key and certificate files are provided)
 24 | - all HTML+CSS is read from a templates directory, which can be freely chosen at
 25 |   server start so as to ease customization of the interface
 26 |  
 27 | ## Docker image
 28 | 
 29 | A docker image maintained by the htwtxt user buckket can be found here:
 30 | <https://hub.docker.com/r/buckket/htwtxt/>
 31 | 
 32 | ## Setup and run
 33 | 
 34 | ### Setup Go build environment
 35 | 
 36 | With htwtxt written in Go, the setup instructions below expect a Go development
 37 | environment – with a somewhat current [go tool](https://golang.org/cmd/go/)
 38 | installed, and a `$GOPATH` set. (Note that the golang package of version 1.3.3
 39 | that is part of Debian Jessie is a bit too old already.) If your system does not
 40 | have such an environment, here's some hints on how to set it up:
 41 | 
 42 |     wget https://storage.googleapis.com/golang/go1.5.3.linux-amd64.tar.gz
 43 |     sudo tar -C /usr/local -xzf go1.5.3.linux-amd64.tar.gz
 44 |     export GOPATH=~/go
 45 |     export PATH=$PATH:/usr/local/go/bin
 46 | 
 47 | (You might want to add the last two lines to your `.bashrc` or whatever usually
 48 | initializes your environment variables. And you might want to replace the
 49 | package pulled by wget by whatever is the newest stable release of Go
 50 | available.)
 51 | 
 52 | ### Clone, build, run
 53 | 
 54 | Once your Go build environment is ready, do this:
 55 | 
 56 |     git clone https://github.com/plomlompom/htwtxt $GOPATH/src/htwtxt
 57 |     go get htwtxt
 58 |     mkdir ~/htwtxt
 59 |     $GOPATH/bin/htwtxt
 60 | 
 61 | This will build and start the server, which will store login and feed data below
 62 | `~/htwtxt`. An alternate directory may be specified with the `--dir` flag.
 63 | 
 64 | ### Writing twtxt messages via API
 65 | 
 66 | Using htwtxt from a web browser for purposes such as writing a twtxt message
 67 | should be self-explanatory (just use the HTML form on the start page). But it's
 68 | also possible to write new messages directly to a twtxt feed via a `POST`
 69 | request to `/feeds`. Just provide appropriate values for the data fields `name`
 70 | and `password` (your login) and `twt` (the message to append). Here's a command
 71 | line example utilizing the curl tool:
 72 | 
 73 |     curl -X POST -d 'name=foo' -d 'password=bar' -d 'twt=Hi there.' \
 74 |     http://test.plomlompom.com:8000/feeds
 75 | 
 76 | ## Tweaking
 77 | 
 78 | ### Configure port number and TLS
 79 | 
 80 | By default, htwtxt serves unencrypted HTTP over port 8000. But the executable
 81 | accepts the flag `--port` to provide an alternate port number, and the flags
 82 | `--cert` and `--key` to provide paths to an SSL certificate and key file to run
 83 | htwtxt as an HTTPS server.
 84 | 
 85 | You might encounter the following issue when trying to set a low port number
 86 | (such as the HTTP standard 80, or the HTTPS standard 443):
 87 | 
 88 |     ListenAndServe: listen tcp :80: bind: permission denied
 89 | 
 90 | This is [a common privilege problem](http://stackoverflow.com/q/413807) and
 91 | [might be solved](http://stackoverflow.com/a/414258) bis this:
 92 | 
 93 |     sudo setcap 'cap_net_bind_service=+ep' $GOPATH/bin/htwtxt
 94 | 
 95 | ### Public or closed sign-up
 96 | 
 97 | By default, sign up / account creation is not open to the web-browsing public.
 98 | The `--signup` flag must be set explicitely to change that. Alternatively, new
 99 | accounts can be added by starting the program with the `--adduser` flag,
100 | followed by an argument of the form `NAME:PASSWORD`.
101 | 
102 | ### Set site owner contact info
103 | 
104 | The server serves a `/info` page (from the `info.html` template) that may
105 | include the site owner's contact info, as given with the `--contact` flag.
106 | 
107 | ### Activate password reset mails
108 | 
109 | Feed owners may add e-mail addresses to their login data to authenticate
110 | themselves to the site operator and receive password reset links when requested.
111 | The password reset mechanism by mail is inactive by default. To activate it, a
112 | set of flags `--mailserver`, `--mailport`, `--mailuser` must be set to describe
113 | a SMTP server and its login from which to send password reset mails to users'
114 | mail addresses. (The site operator will be prompted for his SMTP login password
115 | on program start.) Whether this mechanism is trustworthy or not is up to the
116 | site operator's imagination. Users may set up optional security questions to be
117 | posed on the password reset links they enable by setting their mail address.
118 | 
119 | ### Change HTML templates
120 | 
121 | By default, HTML templates are read out of `$GOPATH/src/htwtxt/templates/`. An
122 | alternate directory can be given with the flag `--templates` (it should contain
123 | template files of the same names as the default ones, however).
124 | 
125 | ## Copyright, license, version
126 | 
127 | htwtxt (c) 2016 Christian Heller a.k.a. [plomlompom](http://www.plomlompom.de),
128 | with template design input by [Kai Kubasta](http://kaikubasta.de).
129 | 
130 | License: Affero GPL version 3, see `./LICENSE`
131 | 
132 | Current version number: 1.0.7
133 | 


--------------------------------------------------------------------------------
/main.go:
--------------------------------------------------------------------------------
  1 | // htwtxt – hosted twtxt server; see README for copyright and license info
  2 | 
  3 | package main
  4 | 
  5 | import "errors"
  6 | import "flag"
  7 | import "fmt"
  8 | import "golang.org/x/crypto/bcrypt"
  9 | import "golang.org/x/crypto/ssh/terminal"
 10 | import "gopkg.in/gomail.v2"
 11 | import "html/template"
 12 | import "io/ioutil"
 13 | import "log"
 14 | import "net"
 15 | import "net/http"
 16 | import "os"
 17 | import "strconv"
 18 | import "strings"
 19 | import "syscall"
 20 | import "time"
 21 | 
 22 | const resetLinkExp = 1800
 23 | const resetWaitTime = 3600 * 24
 24 | const version = "1.0"
 25 | 
 26 | var contact string
 27 | var dialer *gomail.Dialer
 28 | var mailuser string
 29 | var myself string
 30 | var signupOpen bool
 31 | var templ *template.Template
 32 | 
 33 | func execTemplate(w http.ResponseWriter, file string, input string) {
 34 | 	type data struct{ Msg string }
 35 | 	err := templ.ExecuteTemplate(w, file, data{Msg: input})
 36 | 	if err != nil {
 37 | 		log.Fatal("Trouble executing template", err)
 38 | 	}
 39 | }
 40 | 
 41 | func handleTemplate(path, msg string) func(w http.ResponseWriter,
 42 | 	r *http.Request) {
 43 | 	return func(w http.ResponseWriter, r *http.Request) {
 44 | 		execTemplate(w, path, msg)
 45 | 	}
 46 | }
 47 | 
 48 | func onlyLegalRunes(str string) bool {
 49 | 	const legalUrlChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
 50 | 		"abcdefghijklmnopqrstuvwxyz0123456789_"
 51 | 	for _, ru := range str {
 52 | 		if !(strings.ContainsRune(legalUrlChars, ru)) {
 53 | 			return false
 54 | 		}
 55 | 	}
 56 | 	return true
 57 | }
 58 | 
 59 | func checkDelay(w http.ResponseWriter, ip string) (int, error) {
 60 | 	var err error
 61 | 	var openTime int
 62 | 	delay := -1
 63 | 	if tokens, e := getFromFileEntryFor(ipDelaysPath, ip, 3); e == nil {
 64 | 		openTime, err = strconv.Atoi(tokens[0])
 65 | 		if err != nil {
 66 | 			log.Fatal("Can't parse IP delays file", err)
 67 | 		}
 68 | 		delay, err = strconv.Atoi(tokens[1])
 69 | 		if err != nil {
 70 | 			log.Fatal("Can't parse IP delays file", err)
 71 | 		}
 72 | 		if int(time.Now().Unix()) < openTime {
 73 | 			execTemplate(w, "error.html",
 74 | 				"This IP must wait a while for its "+
 75 | 					"next login attempt.")
 76 | 			err = errors.New("")
 77 | 		}
 78 | 	}
 79 | 	return delay, err
 80 | }
 81 | 
 82 | func login(w http.ResponseWriter, r *http.Request) (string, error) {
 83 | 	ip, _, err := net.SplitHostPort(r.RemoteAddr)
 84 | 	if err != nil {
 85 | 		log.Fatal("Can't parse ip from request", err)
 86 | 	}
 87 | 	delay, err := checkDelay(w, ip)
 88 | 	if err != nil {
 89 | 		return "", err
 90 | 	}
 91 | 	name := r.FormValue("name")
 92 | 	pw := r.FormValue("password")
 93 | 	loginValid := false
 94 | 	tokens, err := getFromFileEntryFor(loginsPath, name, 5)
 95 | 	if err == nil && nil == bcrypt.CompareHashAndPassword([]byte(tokens[0]),
 96 | 		[]byte(pw)) {
 97 | 		loginValid = true
 98 | 		if 0 <= delay {
 99 | 			removeLineStartingWith(ipDelaysPath, ip)
100 | 		}
101 | 	}
102 | 	if !loginValid {
103 | 		newLine := delay == -1
104 | 		delay = 2 * delay
105 | 		if -2 == delay {
106 | 			delay = 1
107 | 		}
108 | 		strOpenTime := strconv.Itoa(int(time.Now().Unix()) + delay)
109 | 		strDelay := strconv.Itoa(delay)
110 | 		line := ip + "\t" + strOpenTime + "\t" + strDelay
111 | 		if newLine {
112 | 			appendToFile(ipDelaysPath, line)
113 | 		} else {
114 | 			replaceLineStartingWith(ipDelaysPath, ip, line)
115 | 		}
116 | 		execTemplate(w, "error_login.html", "Bad login.")
117 | 		return name, errors.New("")
118 | 	}
119 | 	return name, nil
120 | }
121 | 
122 | func nameIsLegal(name string) bool {
123 | 	return !("" == name || !onlyLegalRunes(name) || len(name) > 140)
124 | }
125 | 
126 | func passwordIsLegal(password string) bool {
127 | 	return !("" == password)
128 | }
129 | 
130 | func hashFromPw(pw string) string {
131 | 	hash, err := bcrypt.GenerateFromPassword([]byte(pw), bcrypt.DefaultCost)
132 | 	if err != nil {
133 | 		log.Fatal("Can't generate hash", err)
134 | 	}
135 | 	return string(hash)
136 | }
137 | 
138 | func newPassword(w http.ResponseWriter, r *http.Request) (string, error) {
139 | 	pw := r.FormValue("new_password")
140 | 	pw2 := r.FormValue("new_password2")
141 | 	if 0 != strings.Compare(pw, pw2) {
142 | 		return "", errors.New("Password values did not match")
143 | 	} else if !passwordIsLegal(pw) {
144 | 		return "", errors.New("Illegal password.")
145 | 	}
146 | 	return hashFromPw(pw), nil
147 | }
148 | 
149 | func newMailAddress(w http.ResponseWriter, r *http.Request) (string, error) {
150 | 	mail := r.FormValue("mail")
151 | 	if len(mail) > 140 || strings.ContainsRune(mail, '\n') ||
152 | 		strings.ContainsRune(mail, '\t') {
153 | 		return "", errors.New("Illegal mail address.")
154 | 	}
155 | 	return mail, nil
156 | }
157 | 
158 | func newSecurityQuestion(w http.ResponseWriter, r *http.Request) (string,
159 | 	string, error) {
160 | 	secquestion := r.FormValue("secquestion")
161 | 	secanswer := r.FormValue("secanswer")
162 | 	if "" == secquestion || len(secquestion) > 140 ||
163 | 		strings.ContainsRune(secquestion, '\n') ||
164 | 		strings.ContainsRune(secquestion, '\t') {
165 | 		return "", "", errors.New("Illegal security question.")
166 | 	} else if "" == secanswer {
167 | 		return "", "", errors.New("Illegal security question answer.")
168 | 	}
169 | 	return secquestion, hashFromPw(secanswer), nil
170 | }
171 | 
172 | func changeLoginField(w http.ResponseWriter, r *http.Request,
173 | 	getter func(w http.ResponseWriter, r *http.Request) (string, error),
174 | 	position int) {
175 | 	name, err := login(w, r)
176 | 	if err != nil {
177 | 		return
178 | 	}
179 | 	input, err := getter(w, r)
180 | 	if err != nil {
181 | 		execTemplate(w, "error.html", err.Error())
182 | 		return
183 | 	}
184 | 	tokens, err := getFromFileEntryFor(loginsPath, name, 5)
185 | 	if err != nil {
186 | 		log.Fatal("Can't get entry for user", err)
187 | 	}
188 | 	tokens[position] = input
189 | 	replaceLineStartingWith(loginsPath, name,
190 | 		name+"\t"+strings.Join(tokens, "\t"))
191 | 	execTemplate(w, "feedset.html", "")
192 | }
193 | 
194 | func nameMyself(ssl bool, port int) string {
195 | 	resp, err := http.Get("http://myexternalip.com/raw")
196 | 	defer resp.Body.Close()
197 | 	if err != nil {
198 | 		log.Fatal("Trouble getting IP", err)
199 | 	}
200 | 	body, err := ioutil.ReadAll(resp.Body)
201 | 	if err != nil {
202 | 		log.Fatal("Trouble reading IP message body", err)
203 | 	}
204 | 	ip := strings.Replace(string(body), "\n", "", -1)
205 | 	s := ""
206 | 	if ssl {
207 | 		s = "s"
208 | 	}
209 | 	return "http" + s + "://" + ip + ":" + strconv.Itoa(port)
210 | }
211 | 
212 | func addUser(login string) {
213 | 	fields := strings.Split(login, ":")
214 | 	if len(fields) != 2 {
215 | 		log.Fatal("Malformed adduser string, must be NAME:PASSWORD")
216 | 	}
217 | 	name := fields[0]
218 | 	password := fields[1]
219 | 	if !nameIsLegal(name) {
220 | 		log.Fatal("Malformed adduser NAME argument.")
221 | 	}
222 | 	if !passwordIsLegal(password) {
223 | 		log.Fatal("Malformed adduser PASSWORD argument.")
224 | 	}
225 | 	if _, err := getFromFileEntryFor(loginsPath, name, 5); err == nil {
226 | 		log.Fatal("Username already taken.")
227 | 	}
228 | 	hash := hashFromPw(password)
229 | 	appendToFile(loginsPath, name+"\t"+hash+"\t\t\t")
230 | 	fmt.Println("Added user.")
231 | }
232 | 
233 | func readOptions() (string, int, string, int, string, bool) {
234 | 	var mailpw string
235 | 	var mailport int
236 | 	var mailserver string
237 | 	var port int
238 | 	var newLogin string
239 | 	var showVersion bool
240 | 	flag.StringVar(&newLogin, "adduser", "", "instead of starting as "+
241 | 		"server, add user with login NAME:PASSWORD")
242 | 	flag.IntVar(&port, "port", 8000, "port to serve")
243 | 	flag.StringVar(&keyPath, "key", "", "SSL key file")
244 | 	flag.StringVar(&certPath, "cert", "", "SSL certificate file")
245 | 	flag.StringVar(&templPath, "templates",
246 | 		os.Getenv("GOPATH")+"/src/htwtxt/templates",
247 | 		"directory where to expect HTML templates")
248 | 	flag.StringVar(&dataDir, "dir", os.Getenv("HOME")+"/htwtxt",
249 | 		"directory to store feeds and login data")
250 | 	flag.StringVar(&contact, "contact",
251 | 		"[operator passed no contact info to server]",
252 | 		"operator contact info to display on info page")
253 | 	flag.BoolVar(&signupOpen, "signup", false,
254 | 		"enable on-site account creation")
255 | 	flag.BoolVar(&showVersion, "version", false, "show version number")
256 | 	flag.StringVar(&mailserver, "mailserver", "",
257 | 		"SMTP server to send mails through")
258 | 	flag.IntVar(&mailport, "mailport", 0,
259 | 		"port of SMTP server to send mails through")
260 | 	flag.StringVar(&mailuser, "mailuser", "",
261 | 		"username to login with on SMTP server to send mails through")
262 | 	flag.Parse()
263 | 	if "" != mailserver && ("" == mailuser || 0 == mailport) {
264 | 		log.Fatal("Mail server usage needs username and port number")
265 | 	}
266 | 	if ("" == keyPath && "" != certPath) ||
267 | 		("" != keyPath && "" == certPath) {
268 | 		log.Fatal("Expect either both key and certificate or none.")
269 | 	}
270 | 	if "" != mailserver {
271 | 		fmt.Print("Enter password for smtp server: ")
272 | 		bytePassword, err := terminal.ReadPassword(int(syscall.Stdin))
273 | 		if err != nil {
274 | 			log.Fatal("Trouble reading password")
275 | 		}
276 | 		mailpw = string(bytePassword)
277 | 		fmt.Println("")
278 | 	}
279 | 	return mailserver, mailport, mailpw, port, newLogin, showVersion
280 | }
281 | 
282 | func main() {
283 | 	var err error
284 | 	mailserver, mailport, mailpw, port, newLogin, showVersion :=
285 | 		readOptions()
286 | 	if showVersion {
287 | 		fmt.Println("htwtxt", version)
288 | 		return
289 | 	}
290 | 	initFilesAndDirs()
291 | 	if "" != newLogin {
292 | 		addUser(newLogin)
293 | 		return
294 | 	}
295 | 	myself = nameMyself("" != keyPath, port)
296 | 	templ, err = template.New("main").ParseGlob(templPath + "/*.html")
297 | 	if err != nil {
298 | 		log.Fatal("Can't set up new template: ", err)
299 | 	}
300 | 	http.Handle("/", handleRoutes())
301 | 	dialer = gomail.NewPlainDialer(mailserver, mailport, mailuser, mailpw)
302 | 	log.Println("serving at port", port)
303 | 	if "" != keyPath {
304 | 		err = http.ListenAndServeTLS(":"+strconv.Itoa(port),
305 | 			certPath, keyPath, nil)
306 | 	} else {
307 | 		err = http.ListenAndServe(":"+strconv.Itoa(port), nil)
308 | 	}
309 | 	if err != nil {
310 | 		log.Fatal("ListenAndServe: ", err)
311 | 	}
312 | }
313 | 


--------------------------------------------------------------------------------
/handlers.go:
--------------------------------------------------------------------------------
  1 | package main
  2 | 
  3 | import "bufio"
  4 | import "crypto/rand"
  5 | import "encoding/base64"
  6 | import "golang.org/x/crypto/bcrypt"
  7 | import "gopkg.in/gomail.v2"
  8 | import "log"
  9 | import "github.com/gorilla/mux"
 10 | import "net/http"
 11 | import "os"
 12 | import "strconv"
 13 | import "strings"
 14 | import "time"
 15 | 
 16 | func passwordResetRequestGetHandler(w http.ResponseWriter, r *http.Request) {
 17 | 	if "" == mailuser {
 18 | 		execTemplate(w, "nopwresetrequest.html", "")
 19 | 	} else {
 20 | 		execTemplate(w, "pwresetrequest.html", "")
 21 | 	}
 22 | }
 23 | 
 24 | func passwordResetRequestPostHandler(w http.ResponseWriter, r *http.Request) {
 25 | 	preparePasswordReset := func(name string) {
 26 | 		if "" == mailuser {
 27 | 			return
 28 | 		}
 29 | 		now := int(time.Now().Unix())
 30 | 		tokens, errWait := getFromFileEntryFor(pwResetWaitPath, name, 2)
 31 | 		if errWait == nil {
 32 | 			lastTime, err := strconv.Atoi(tokens[0])
 33 | 			if err != nil {
 34 | 				log.Fatal("Trouble parsing password reset "+
 35 | 					"wait times", err)
 36 | 			}
 37 | 			if lastTime+resetWaitTime >= now {
 38 | 				return
 39 | 			}
 40 | 		}
 41 | 		var target string
 42 | 		tokens, err := getFromFileEntryFor(loginsPath, name, 5)
 43 | 		if err != nil {
 44 | 			return
 45 | 		} else if "" == tokens[1] {
 46 | 			return
 47 | 		}
 48 | 		target = tokens[1]
 49 | 		b := make([]byte, 64)
 50 | 		if _, err := rand.Read(b); err != nil {
 51 | 			log.Fatal("Random string generation failed", err)
 52 | 		}
 53 | 		urlPart := base64.URLEncoding.EncodeToString(b)
 54 | 		strTime := strconv.Itoa(now)
 55 | 		appendToFile(pwResetPath, urlPart+"\t"+name+"\t"+strTime)
 56 | 		m := gomail.NewMessage()
 57 | 		m.SetHeader("From", mailuser)
 58 | 		m.SetHeader("To", target)
 59 | 		m.SetHeader("Subject", "password reset link")
 60 | 		msg := myself + "/passwordreset/" + urlPart
 61 | 		m.SetBody("text/plain", msg)
 62 | 		if err := dialer.DialAndSend(m); err != nil {
 63 | 			log.Fatal("Can't send mail", err)
 64 | 		}
 65 | 		line := name + "\t" + strTime
 66 | 		if nil == errWait {
 67 | 			replaceLineStartingWith(pwResetWaitPath, name, line)
 68 | 		} else {
 69 | 			appendToFile(pwResetWaitPath, line)
 70 | 		}
 71 | 	}
 72 | 	go preparePasswordReset(r.FormValue("name"))
 73 | 	http.Redirect(w, r, "/", 302)
 74 | }
 75 | 
 76 | func passwordResetLinkGetHandler(w http.ResponseWriter, r *http.Request) {
 77 | 	urlPart := mux.Vars(r)["secret"]
 78 | 	tokens, err := getFromFileEntryFor(pwResetPath, urlPart, 3)
 79 | 	if err != nil {
 80 | 		http.Redirect(w, r, "/404", 302)
 81 | 		return
 82 | 	}
 83 | 	createTime, err := strconv.Atoi(tokens[1])
 84 | 	if err != nil {
 85 | 		log.Fatal("Can't read time from pw reset file", err)
 86 | 	}
 87 | 	if createTime+resetLinkExp < int(time.Now().Unix()) {
 88 | 		http.Redirect(w, r, "/404", 302)
 89 | 		return
 90 | 	}
 91 | 	name := tokens[0]
 92 | 	tokensUser, err := getFromFileEntryFor(loginsPath, name,
 93 | 		5)
 94 | 	if err != nil {
 95 | 		log.Fatal("Can't read from loings file", err)
 96 | 	}
 97 | 	if "" != tokensUser[2] {
 98 | 		type data struct {
 99 | 			Secret   string
100 | 			Question string
101 | 		}
102 | 		err := templ.ExecuteTemplate(w,
103 | 			"pwresetquestion.html", data{
104 | 				Secret:   urlPart,
105 | 				Question: tokensUser[2]})
106 | 		if err != nil {
107 | 			log.Fatal("Trouble executing template", err)
108 | 		}
109 | 		return
110 | 	}
111 | 	execTemplate(w, "pwreset.html", urlPart)
112 | }
113 | 
114 | func passwordResetLinkPostHandler(w http.ResponseWriter, r *http.Request) {
115 | 	urlPart := mux.Vars(r)["secret"]
116 | 	name := r.FormValue("name")
117 | 	tokens, err := getFromFileEntryFor(pwResetPath, urlPart, 3)
118 | 	if err != nil {
119 | 		http.Redirect(w, r, "/404", 302)
120 | 		return
121 | 	}
122 | 	createTime, err := strconv.Atoi(tokens[1])
123 | 	if err != nil {
124 | 		log.Fatal("Can't read time from pw reset file", err)
125 | 	}
126 | 	if createTime+resetLinkExp < int(time.Now().Unix()) {
127 | 		http.Redirect(w, r, "/404", 302)
128 | 		return
129 | 	}
130 | 	if tokens[0] != name {
131 | 		execTemplate(w, "error.html", "Wrong answer(s).")
132 | 		removeLineStartingWith(pwResetPath, urlPart)
133 | 		return
134 | 	}
135 | 	tokensUser, err := getFromFileEntryFor(loginsPath, name, 5)
136 | 	if err != nil {
137 | 		log.Fatal("Can't get entry for user", err)
138 | 	}
139 | 	if "" != tokensUser[2] &&
140 | 		nil != bcrypt.CompareHashAndPassword([]byte(tokensUser[3]),
141 | 			[]byte(r.FormValue("secanswer"))) {
142 | 		execTemplate(w, "error.html", "Wrong answer(s).")
143 | 		removeLineStartingWith(pwResetPath, urlPart)
144 | 		return
145 | 	}
146 | 	hash, err := newPassword(w, r)
147 | 	if err != nil {
148 | 		execTemplate(w, "error.html", err.Error())
149 | 		return
150 | 	}
151 | 	tokensUser[0] = hash
152 | 	line := name + "\t" + strings.Join(tokensUser, "\t")
153 | 	replaceLineStartingWith(loginsPath, tokens[0], line)
154 | 	removeLineStartingWith(pwResetPath, urlPart)
155 | 	execTemplate(w, "feedset.html", "")
156 | }
157 | 
158 | func signUpFormHandler(w http.ResponseWriter, r *http.Request) {
159 | 	if !signupOpen {
160 | 		execTemplate(w, "nosignup.html", "")
161 | 		return
162 | 	}
163 | 	execTemplate(w, "signupform.html", "")
164 | }
165 | 
166 | func signUpHandler(w http.ResponseWriter, r *http.Request) {
167 | 	if !signupOpen {
168 | 		execTemplate(w, "error.html",
169 | 			"Account creation currently not allowed.")
170 | 		return
171 | 	}
172 | 	name := r.FormValue("name")
173 | 	if !nameIsLegal(name) {
174 | 		execTemplate(w, "error.html", "Illegal name.")
175 | 		return
176 | 	}
177 | 	if _, err := getFromFileEntryFor(loginsPath, name, 5); err == nil {
178 | 		execTemplate(w, "error.html", "Username taken.")
179 | 		return
180 | 	}
181 | 	hash, err := newPassword(w, r)
182 | 	if err != nil {
183 | 		execTemplate(w, "error.html", err.Error())
184 | 		return
185 | 	}
186 | 	mail := ""
187 | 	if "" != r.FormValue("mail") {
188 | 		mail, err = newMailAddress(w, r)
189 | 		if err != nil {
190 | 			execTemplate(w, "error.html", err.Error())
191 | 			return
192 | 		}
193 | 	}
194 | 	var secquestion, secanswer string
195 | 	if "" != r.FormValue("secquestion") || "" != r.FormValue("secanswer") {
196 | 		secquestion, secanswer, err = newSecurityQuestion(w, r)
197 | 		if err != nil {
198 | 			execTemplate(w, "error.html", err.Error())
199 | 			return
200 | 		}
201 | 	}
202 | 	appendToFile(loginsPath,
203 | 		name+"\t"+hash+"\t"+mail+"\t"+secquestion+"\t"+secanswer)
204 | 	execTemplate(w, "feedset.html", "")
205 | }
206 | 
207 | func accountSetPwHandler(w http.ResponseWriter, r *http.Request) {
208 | 	changeLoginField(w, r, newPassword, 0)
209 | }
210 | 
211 | func accountSetMailHandler(w http.ResponseWriter, r *http.Request) {
212 | 	changeLoginField(w, r, newMailAddress, 1)
213 | }
214 | 
215 | func accountSetQuestionHandler(w http.ResponseWriter, r *http.Request) {
216 | 	name, err := login(w, r)
217 | 	if err != nil {
218 | 		return
219 | 	}
220 | 	var secquestion, secanswer string
221 | 	if "" != r.FormValue("secquestion") || "" != r.FormValue("secanswer") {
222 | 		secquestion, secanswer, err = newSecurityQuestion(w, r)
223 | 		if err != nil {
224 | 			execTemplate(w, "error.html", err.Error())
225 | 			return
226 | 		}
227 | 	}
228 | 	tokens, err := getFromFileEntryFor(loginsPath, name, 5)
229 | 	if err != nil {
230 | 		log.Fatal("Can't get entry for user", err)
231 | 	}
232 | 	tokens[2] = secquestion
233 | 	tokens[3] = secanswer
234 | 	replaceLineStartingWith(loginsPath, name,
235 | 		name+"\t"+strings.Join(tokens, "\t"))
236 | 	execTemplate(w, "feedset.html", "")
237 | }
238 | 
239 | func listHandler(w http.ResponseWriter, r *http.Request) {
240 | 	file := openFile(loginsPath)
241 | 	defer file.Close()
242 | 	scanner := bufio.NewScanner(bufio.NewReader(file))
243 | 	var dir []string
244 | 	tokens := tokensFromLine(scanner, 5)
245 | 	for 0 != len(tokens) {
246 | 		dir = append(dir, tokens[0])
247 | 		tokens = tokensFromLine(scanner, 5)
248 | 	}
249 | 	type data struct{ Dir []string }
250 | 	err := templ.ExecuteTemplate(w, "list.html", data{Dir: dir})
251 | 	if err != nil {
252 | 		log.Fatal("Trouble executing template", err)
253 | 	}
254 | }
255 | 
256 | func twtxtPostHandler(w http.ResponseWriter, r *http.Request) {
257 | 	name, err := login(w, r)
258 | 	if err != nil {
259 | 		return
260 | 	}
261 | 	text := r.FormValue("twt")
262 | 	twtsFile := feedsPath + "/" + name
263 | 	createFileIfNotExists(twtsFile)
264 | 	text = strings.Replace(text, "\n", " ", -1)
265 | 	appendToFile(twtsFile, time.Now().Format(time.RFC3339)+"\t"+text)
266 | 	http.Redirect(w, r, "/"+feedsDir+"/"+name, 302)
267 | }
268 | 
269 | func twtxtHandler(w http.ResponseWriter, r *http.Request) {
270 | 	name := mux.Vars(r)["name"]
271 | 	if !onlyLegalRunes(name) {
272 | 		execTemplate(w, "error.html", "Bad path.")
273 | 		return
274 | 	}
275 | 	path := feedsPath + "/" + name
276 | 	if _, err := os.Stat(path); err != nil {
277 | 		execTemplate(w, "error.html", "Empty twtxt for user.")
278 | 		return
279 | 	}
280 | 	http.ServeFile(w, r, path)
281 | }
282 | 
283 | func handleRoutes() *mux.Router {
284 | 	router := mux.NewRouter()
285 | 	router.HandleFunc("/", handleTemplate("index.html", ""))
286 | 	router.HandleFunc("/feeds", listHandler).Methods("GET")
287 | 	router.HandleFunc("/feeds/", listHandler)
288 | 	router.HandleFunc("/accountsetquestion",
289 | 		handleTemplate("accountsetquestion.html", "")).Methods("GET")
290 | 	router.HandleFunc("/accountsetquestion", accountSetQuestionHandler).
291 | 		Methods("POST")
292 | 	router.HandleFunc("/accountsetmail",
293 | 		handleTemplate("accountsetmail.html", "")).Methods("GET")
294 | 	router.HandleFunc("/accountsetmail", accountSetMailHandler).
295 | 		Methods("POST")
296 | 	router.HandleFunc("/accountsetpw", handleTemplate("accountsetpw.html",
297 | 		"")).Methods("GET")
298 | 	router.HandleFunc("/accountsetpw", accountSetPwHandler).Methods("POST")
299 | 	router.HandleFunc("/account", handleTemplate("account.html", ""))
300 | 	router.HandleFunc("/signup", signUpFormHandler).Methods("GET")
301 | 	router.HandleFunc("/signup", signUpHandler).Methods("POST")
302 | 	router.HandleFunc("/feeds", twtxtPostHandler).Methods("POST")
303 | 	router.HandleFunc("/feeds/{name}", twtxtHandler)
304 | 	router.HandleFunc("/info", handleTemplate("info.html", contact))
305 | 	router.HandleFunc("/passwordreset", passwordResetRequestPostHandler).
306 | 		Methods("POST")
307 | 	router.HandleFunc("/passwordreset", passwordResetRequestGetHandler).
308 | 		Methods("GET")
309 | 	router.HandleFunc("/passwordreset/{secret}",
310 | 		passwordResetLinkGetHandler).Methods("GET")
311 | 	router.HandleFunc("/passwordreset/{secret}",
312 | 		passwordResetLinkPostHandler).Methods("POST")
313 | 	router.HandleFunc("/style.css",
314 | 		func(w http.ResponseWriter, r *http.Request) {
315 | 			http.ServeFile(w, r, templPath+"/style.css")
316 | 		})
317 | 	return router
318 | }
319 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
  1 |                     GNU AFFERO GENERAL PUBLIC LICENSE
  2 |                        Version 3, 19 November 2007
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384 | not survive such relicensing or conveying.
385 | 
386 |   If you add terms to a covered work in accord with this section, you
387 | must place, in the relevant source files, a statement of the
388 | additional terms that apply to those files, or a notice indicating
389 | where to find the applicable terms.
390 | 
391 |   Additional terms, permissive or non-permissive, may be stated in the
392 | form of a separately written license, or stated as exceptions;
393 | the above requirements apply either way.
394 | 
395 |   8. Termination.
396 | 
397 |   You may not propagate or modify a covered work except as expressly
398 | provided under this License.  Any attempt otherwise to propagate or
399 | modify it is void, and will automatically terminate your rights under
400 | this License (including any patent licenses granted under the third
401 | paragraph of section 11).
402 | 
403 |   However, if you cease all violation of this License, then your
404 | license from a particular copyright holder is reinstated (a)
405 | provisionally, unless and until the copyright holder explicitly and
406 | finally terminates your license, and (b) permanently, if the copyright
407 | holder fails to notify you of the violation by some reasonable means
408 | prior to 60 days after the cessation.
409 | 
410 |   Moreover, your license from a particular copyright holder is
411 | reinstated permanently if the copyright holder notifies you of the
412 | violation by some reasonable means, this is the first time you have
413 | received notice of violation of this License (for any work) from that
414 | copyright holder, and you cure the violation prior to 30 days after
415 | your receipt of the notice.
416 | 
417 |   Termination of your rights under this section does not terminate the
418 | licenses of parties who have received copies or rights from you under
419 | this License.  If your rights have been terminated and not permanently
420 | reinstated, you do not qualify to receive new licenses for the same
421 | material under section 10.
422 | 
423 |   9. Acceptance Not Required for Having Copies.
424 | 
425 |   You are not required to accept this License in order to receive or
426 | run a copy of the Program.  Ancillary propagation of a covered work
427 | occurring solely as a consequence of using peer-to-peer transmission
428 | to receive a copy likewise does not require acceptance.  However,
429 | nothing other than this License grants you permission to propagate or
430 | modify any covered work.  These actions infringe copyright if you do
431 | not accept this License.  Therefore, by modifying or propagating a
432 | covered work, you indicate your acceptance of this License to do so.
433 | 
434 |   10. Automatic Licensing of Downstream Recipients.
435 | 
436 |   Each time you convey a covered work, the recipient automatically
437 | receives a license from the original licensors, to run, modify and
438 | propagate that work, subject to this License.  You are not responsible
439 | for enforcing compliance by third parties with this License.
440 | 
441 |   An "entity transaction" is a transaction transferring control of an
442 | organization, or substantially all assets of one, or subdividing an
443 | organization, or merging organizations.  If propagation of a covered
444 | work results from an entity transaction, each party to that
445 | transaction who receives a copy of the work also receives whatever
446 | licenses to the work the party's predecessor in interest had or could
447 | give under the previous paragraph, plus a right to possession of the
448 | Corresponding Source of the work from the predecessor in interest, if
449 | the predecessor has it or can get it with reasonable efforts.
450 | 
451 |   You may not impose any further restrictions on the exercise of the
452 | rights granted or affirmed under this License.  For example, you may
453 | not impose a license fee, royalty, or other charge for exercise of
454 | rights granted under this License, and you may not initiate litigation
455 | (including a cross-claim or counterclaim in a lawsuit) alleging that
456 | any patent claim is infringed by making, using, selling, offering for
457 | sale, or importing the Program or any portion of it.
458 | 
459 |   11. Patents.
460 | 
461 |   A "contributor" is a copyright holder who authorizes use under this
462 | License of the Program or a work on which the Program is based.  The
463 | work thus licensed is called the contributor's "contributor version".
464 | 
465 |   A contributor's "essential patent claims" are all patent claims
466 | owned or controlled by the contributor, whether already acquired or
467 | hereafter acquired, that would be infringed by some manner, permitted
468 | by this License, of making, using, or selling its contributor version,
469 | but do not include claims that would be infringed only as a
470 | consequence of further modification of the contributor version.  For
471 | purposes of this definition, "control" includes the right to grant
472 | patent sublicenses in a manner consistent with the requirements of
473 | this License.
474 | 
475 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
476 | patent license under the contributor's essential patent claims, to
477 | make, use, sell, offer for sale, import and otherwise run, modify and
478 | propagate the contents of its contributor version.
479 | 
480 |   In the following three paragraphs, a "patent license" is any express
481 | agreement or commitment, however denominated, not to enforce a patent
482 | (such as an express permission to practice a patent or covenant not to
483 | sue for patent infringement).  To "grant" such a patent license to a
484 | party means to make such an agreement or commitment not to enforce a
485 | patent against the party.
486 | 
487 |   If you convey a covered work, knowingly relying on a patent license,
488 | and the Corresponding Source of the work is not available for anyone
489 | to copy, free of charge and under the terms of this License, through a
490 | publicly available network server or other readily accessible means,
491 | then you must either (1) cause the Corresponding Source to be so
492 | available, or (2) arrange to deprive yourself of the benefit of the
493 | patent license for this particular work, or (3) arrange, in a manner
494 | consistent with the requirements of this License, to extend the patent
495 | license to downstream recipients.  "Knowingly relying" means you have
496 | actual knowledge that, but for the patent license, your conveying the
497 | covered work in a country, or your recipient's use of the covered work
498 | in a country, would infringe one or more identifiable patents in that
499 | country that you have reason to believe are valid.
500 | 
501 |   If, pursuant to or in connection with a single transaction or
502 | arrangement, you convey, or propagate by procuring conveyance of, a
503 | covered work, and grant a patent license to some of the parties
504 | receiving the covered work authorizing them to use, propagate, modify
505 | or convey a specific copy of the covered work, then the patent license
506 | you grant is automatically extended to all recipients of the covered
507 | work and works based on it.
508 | 
509 |   A patent license is "discriminatory" if it does not include within
510 | the scope of its coverage, prohibits the exercise of, or is
511 | conditioned on the non-exercise of one or more of the rights that are
512 | specifically granted under this License.  You may not convey a covered
513 | work if you are a party to an arrangement with a third party that is
514 | in the business of distributing software, under which you make payment
515 | to the third party based on the extent of your activity of conveying
516 | the work, and under which the third party grants, to any of the
517 | parties who would receive the covered work from you, a discriminatory
518 | patent license (a) in connection with copies of the covered work
519 | conveyed by you (or copies made from those copies), or (b) primarily
520 | for and in connection with specific products or compilations that
521 | contain the covered work, unless you entered into that arrangement,
522 | or that patent license was granted, prior to 28 March 2007.
523 | 
524 |   Nothing in this License shall be construed as excluding or limiting
525 | any implied license or other defenses to infringement that may
526 | otherwise be available to you under applicable patent law.
527 | 
528 |   12. No Surrender of Others' Freedom.
529 | 
530 |   If conditions are imposed on you (whether by court order, agreement or
531 | otherwise) that contradict the conditions of this License, they do not
532 | excuse you from the conditions of this License.  If you cannot convey a
533 | covered work so as to satisfy simultaneously your obligations under this
534 | License and any other pertinent obligations, then as a consequence you may
535 | not convey it at all.  For example, if you agree to terms that obligate you
536 | to collect a royalty for further conveying from those to whom you convey
537 | the Program, the only way you could satisfy both those terms and this
538 | License would be to refrain entirely from conveying the Program.
539 | 
540 |   13. Remote Network Interaction; Use with the GNU General Public License.
541 | 
542 |   Notwithstanding any other provision of this License, if you modify the
543 | Program, your modified version must prominently offer all users
544 | interacting with it remotely through a computer network (if your version
545 | supports such interaction) an opportunity to receive the Corresponding
546 | Source of your version by providing access to the Corresponding Source
547 | from a network server at no charge, through some standard or customary
548 | means of facilitating copying of software.  This Corresponding Source
549 | shall include the Corresponding Source for any work covered by version 3
550 | of the GNU General Public License that is incorporated pursuant to the
551 | following paragraph.
552 | 
553 |   Notwithstanding any other provision of this License, you have
554 | permission to link or combine any covered work with a work licensed
555 | under version 3 of the GNU General Public License into a single
556 | combined work, and to convey the resulting work.  The terms of this
557 | License will continue to apply to the part which is the covered work,
558 | but the work with which it is combined will remain governed by version
559 | 3 of the GNU General Public License.
560 | 
561 |   14. Revised Versions of this License.
562 | 
563 |   The Free Software Foundation may publish revised and/or new versions of
564 | the GNU Affero General Public License from time to time.  Such new versions
565 | will be similar in spirit to the present version, but may differ in detail to
566 | address new problems or concerns.
567 | 
568 |   Each version is given a distinguishing version number.  If the
569 | Program specifies that a certain numbered version of the GNU Affero General
570 | Public License "or any later version" applies to it, you have the
571 | option of following the terms and conditions either of that numbered
572 | version or of any later version published by the Free Software
573 | Foundation.  If the Program does not specify a version number of the
574 | GNU Affero General Public License, you may choose any version ever published
575 | by the Free Software Foundation.
576 | 
577 |   If the Program specifies that a proxy can decide which future
578 | versions of the GNU Affero General Public License can be used, that proxy's
579 | public statement of acceptance of a version permanently authorizes you
580 | to choose that version for the Program.
581 | 
582 |   Later license versions may give you additional or different
583 | permissions.  However, no additional obligations are imposed on any
584 | author or copyright holder as a result of your choosing to follow a
585 | later version.
586 | 
587 |   15. Disclaimer of Warranty.
588 | 
589 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
590 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
591 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
592 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
593 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
594 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
595 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
596 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
597 | 
598 |   16. Limitation of Liability.
599 | 
600 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
601 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
602 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
603 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
604 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
605 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
606 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
607 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
608 | SUCH DAMAGES.
609 | 
610 |   17. Interpretation of Sections 15 and 16.
611 | 
612 |   If the disclaimer of warranty and limitation of liability provided
613 | above cannot be given local legal effect according to their terms,
614 | reviewing courts shall apply local law that most closely approximates
615 | an absolute waiver of all civil liability in connection with the
616 | Program, unless a warranty or assumption of liability accompanies a
617 | copy of the Program in return for a fee.
618 | 
619 |                      END OF TERMS AND CONDITIONS
620 | 
621 |             How to Apply These Terms to Your New Programs
622 | 
623 |   If you develop a new program, and you want it to be of the greatest
624 | possible use to the public, the best way to achieve this is to make it
625 | free software which everyone can redistribute and change under these terms.
626 | 
627 |   To do so, attach the following notices to the program.  It is safest
628 | to attach them to the start of each source file to most effectively
629 | state the exclusion of warranty; and each file should have at least
630 | the "copyright" line and a pointer to where the full notice is found.
631 | 
632 |     <one line to give the program's name and a brief idea of what it does.>
633 |     Copyright (C) <year>  <name of author>
634 | 
635 |     This program is free software: you can redistribute it and/or modify
636 |     it under the terms of the GNU Affero General Public License as published by
637 |     the Free Software Foundation, either version 3 of the License, or
638 |     (at your option) any later version.
639 | 
640 |     This program is distributed in the hope that it will be useful,
641 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
642 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
643 |     GNU Affero General Public License for more details.
644 | 
645 |     You should have received a copy of the GNU Affero General Public License
646 |     along with this program.  If not, see <http://www.gnu.org/licenses/>.
647 | 
648 | Also add information on how to contact you by electronic and paper mail.
649 | 
650 |   If your software can interact with users remotely through a computer
651 | network, you should also make sure that it provides a way for users to
652 | get its source.  For example, if your program is a web application, its
653 | interface could display a "Source" link that leads users to an archive
654 | of the code.  There are many ways you could offer source, and different
655 | solutions will be better for different programs; see section 13 for the
656 | specific requirements.
657 | 
658 |   You should also get your employer (if you work as a programmer) or school,
659 | if any, to sign a "copyright disclaimer" for the program, if necessary.
660 | For more information on this, and how to apply and follow the GNU AGPL, see
661 | <http://www.gnu.org/licenses/>.
662 | 


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