1 /*
2 * lws-minimal-secure-streams-server
3 *
4 * Written in 2010-2020 by Andy Green <andy@warmcat.com>
5 *
6 * This file is made available under the Creative Commons CC0 1.0
7 * Universal Public Domain Dedication.
8 */
9
10 #include <libwebsockets.h>
11 #include <assert.h>
12
13 extern int interrupted, bad, multipart;
14
15 static const char *html =
16 /* normally we serve this... */
17 "<head><meta content=\"text/html;charset=utf-8\" "
18 "http-equiv=\"Content-Type\"><script>"
19 " var ws = new WebSocket(\"wss://localhost:7681\", \"mywsprotocol\");"
20 "try { ws.onopen = function() { console.log(\"open\"); }; "
21 "ws.onmessage = function got_packet(msg) { "
22 "var s=\"\"; s += msg.data; "
23 "document.getElementById(\"wsd\").innerHTML = s; };"
24 "} catch(exception) {"
25 "alert(\"<p>Error\" + exception); }"
26 "</script></head><html><body>"
27 "Hello from the web server<br>"
28 "<div id=\"wsd\"></div>"
29 "</body></html>",
30
31 *multipart_html =
32 /*
33 * If you use -m commandline switch we send this instead, as
34 * multipart/form-data
35 */
36 "--aBoundaryString\r\n"
37 "Content-Disposition: form-data; name=\"myFile\"; filename=\"xxx.txt\"\r\n"
38 "Content-Type: text/plain\r\n"
39 "\r\n"
40 "The file contents\r\n"
41 "--aBoundaryString\r\n"
42 "Content-Disposition: form-data; name=\"myField\"\r\n"
43 "\r\n"
44 "(data)\r\n"
45 "--aBoundaryString--\r\n";
46
47
48 typedef struct myss {
49 struct lws_ss_handle *ss;
50 void *opaque_data;
51 /* ... application specific state ... */
52
53 lws_sorted_usec_list_t sul;
54 int count;
55 char upgraded;
56
57 } myss_srv_t;
58
59 /*
60 * This is the Secure Streams Server RX and TX for HTTP(S)
61 */
62
63 static lws_ss_state_return_t
myss_srv_rx(void * userobj,const uint8_t * buf,size_t len,int flags)64 myss_srv_rx(void *userobj, const uint8_t *buf, size_t len, int flags)
65 {
66 // myss_srv_t *m = (myss_srv_t *)userobj;
67
68 lwsl_user("%s: len %d, flags: %d\n", __func__, (int)len, flags);
69 lwsl_hexdump_info(buf, len);
70
71 /*
72 * If we received the whole message, for our example it means
73 * we are done.
74 */
75 if (flags & LWSSS_FLAG_EOM) {
76 bad = 0;
77 interrupted = 1;
78 }
79
80 return 0;
81 }
82
83 static lws_ss_state_return_t
myss_srv_tx(void * userobj,lws_ss_tx_ordinal_t ord,uint8_t * buf,size_t * len,int * flags)84 myss_srv_tx(void *userobj, lws_ss_tx_ordinal_t ord, uint8_t *buf, size_t *len,
85 int *flags)
86 {
87 myss_srv_t *m = (myss_srv_t *)userobj;
88 const char *send = html;
89
90 if (m->upgraded)
91 return LWSSSSRET_TX_DONT_SEND;
92
93 if (multipart)
94 send = multipart_html;
95
96 *flags = LWSSS_FLAG_SOM | LWSSS_FLAG_EOM;
97
98 lws_strncpy((char *)buf, send, *len);
99 *len = strlen(send);
100
101 return 0;
102 }
103
104 /*
105 * This is the Secure Streams Server RX and TX for WS(S)... when we get a
106 * state that the underlying connection upgraded protocol, we switch the stream
107 * rx and tx handlers to here.
108 */
109
110 static lws_ss_state_return_t
myss_ws_rx(void * userobj,const uint8_t * buf,size_t len,int flags)111 myss_ws_rx(void *userobj, const uint8_t *buf, size_t len, int flags)
112 {
113 // myss_srv_t *m = (myss_srv_t *)userobj;
114
115 lwsl_user("%s: len %d, flags: %d\n", __func__, (int)len, flags);
116 lwsl_hexdump_info(buf, len);
117
118 /*
119 * If we received the whole message, for our example it means
120 * we are done.
121 */
122 if (flags & LWSSS_FLAG_EOM) {
123 bad = 0;
124 interrupted = 1;
125 }
126
127 return 0;
128 }
129
130 /* this is the callback that mediates sending the incrementing number */
131
132 static void
spam_sul_cb(struct lws_sorted_usec_list * sul)133 spam_sul_cb(struct lws_sorted_usec_list *sul)
134 {
135 myss_srv_t *m = lws_container_of(sul, myss_srv_t, sul);
136
137 if (!lws_ss_request_tx(m->ss))
138 lws_sul_schedule(lws_ss_get_context(m->ss), 0, &m->sul, spam_sul_cb,
139 100 * LWS_US_PER_MS);
140 }
141
142 static lws_ss_state_return_t
myss_ws_tx(void * userobj,lws_ss_tx_ordinal_t ord,uint8_t * buf,size_t * len,int * flags)143 myss_ws_tx(void *userobj, lws_ss_tx_ordinal_t ord, uint8_t *buf, size_t *len,
144 int *flags)
145 {
146 myss_srv_t *m = (myss_srv_t *)userobj;
147
148 *flags = LWSSS_FLAG_SOM | LWSSS_FLAG_EOM;
149
150 *len = (unsigned int)lws_snprintf((char *)buf, *len, "hello from ws %d", m->count++);
151
152 lws_sul_schedule(lws_ss_get_context(m->ss), 0, &m->sul, spam_sul_cb,
153 100 * LWS_US_PER_MS);
154
155 return 0;
156 }
157
158 static lws_ss_state_return_t
myss_srv_state(void * userobj,void * sh,lws_ss_constate_t state,lws_ss_tx_ordinal_t ack)159 myss_srv_state(void *userobj, void *sh, lws_ss_constate_t state,
160 lws_ss_tx_ordinal_t ack)
161 {
162 myss_srv_t *m = (myss_srv_t *)userobj;
163
164 lwsl_user("%s: %p %s, ord 0x%x\n", __func__, m->ss,
165 lws_ss_state_name((int)state), (unsigned int)ack);
166
167 switch (state) {
168 case LWSSSCS_DISCONNECTED:
169 lws_sul_cancel(&m->sul);
170 break;
171 case LWSSSCS_CREATING:
172 return lws_ss_request_tx(m->ss);
173
174 case LWSSSCS_ALL_RETRIES_FAILED:
175 /* if we're out of retries, we want to close the app and FAIL */
176 interrupted = 1;
177 break;
178
179 case LWSSSCS_SERVER_TXN:
180 /*
181 * The underlying protocol started a transaction, let's
182 * describe how we want to complete it. We can defer this until
183 * later, eg, after we have consumed any rx that's coming with
184 * the client's transaction initiation phase, but in this
185 * example we know what we want to do already.
186 *
187 * We do want to ack the transaction...
188 */
189 lws_ss_server_ack(m->ss, 0);
190 /*
191 * ... it's going to be either text/html or multipart ...
192 */
193 if (multipart) {
194 if (lws_ss_set_metadata(m->ss, "mime",
195 "multipart/form-data; boundary=aBoundaryString", 45))
196 return LWSSSSRET_DISCONNECT_ME;
197 } else
198 if (lws_ss_set_metadata(m->ss, "mime", "text/html", 9))
199 return LWSSSSRET_DISCONNECT_ME;
200 /*
201 * ...it's going to be whatever size it is (and request tx)
202 */
203 return lws_ss_request_tx_len(m->ss, (unsigned long)
204 (multipart ? strlen(multipart_html) :
205 strlen(html)));
206
207 case LWSSSCS_SERVER_UPGRADE:
208
209 /*
210 * This is sent when the underlying protocol has experienced
211 * an upgrade, eg, http->ws... it's a one-way upgrade on this
212 * stream, change the handlers to deal with the kind of
213 * messages we send on ws
214 */
215
216 m->upgraded = 1;
217 lws_ss_change_handlers(m->ss, myss_ws_rx, myss_ws_tx, NULL);
218 return lws_ss_request_tx(m->ss); /* we want to start sending numbers */
219
220 default:
221 break;
222 }
223
224 return 0;
225 }
226
227 const lws_ss_info_t ssi_server = {
228 .handle_offset = offsetof(myss_srv_t, ss),
229 .opaque_user_data_offset = offsetof(myss_srv_t, opaque_data),
230 .streamtype = "myserver",
231 .rx = myss_srv_rx,
232 .tx = myss_srv_tx,
233 .state = myss_srv_state,
234 .user_alloc = sizeof(myss_srv_t),
235 };
236