1 /*
2 * ws protocol handler plugin for "POST demo"
3 *
4 * Written in 2010-2019 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 * The person who associated a work with this deed has dedicated
10 * the work to the public domain by waiving all of his or her rights
11 * to the work worldwide under copyright law, including all related
12 * and neighboring rights, to the extent allowed by law. You can copy,
13 * modify, distribute and perform the work, even for commercial purposes,
14 * all without asking permission.
15 *
16 * These test plugins are intended to be adapted for use in your code, which
17 * may be proprietary. So unlike the library itself, they are licensed
18 * Public Domain.
19 */
20
21 #if !defined (LWS_PLUGIN_STATIC)
22 #define LWS_DLL
23 #define LWS_INTERNAL
24 #include <libwebsockets.h>
25 #endif
26
27 #include <stdlib.h>
28 #include <string.h>
29 #include <fcntl.h>
30 #include <sys/types.h>
31 #include <sys/stat.h>
32 #ifdef WIN32
33 #include <io.h>
34 #endif
35 #include <stdio.h>
36
37 struct per_session_data__post_demo {
38 struct lws_spa *spa;
39 char result[LWS_PRE + LWS_RECOMMENDED_MIN_HEADER_SPACE];
40 char filename[64];
41 long file_length;
42 #if !defined(LWS_WITH_ESP32)
43 lws_filefd_type fd;
44 #endif
45 uint8_t completed:1;
46 uint8_t sent_headers:1;
47 uint8_t sent_body:1;
48 };
49
50 static const char * const param_names[] = {
51 "text",
52 "send",
53 "file",
54 "upload",
55 };
56
57 enum enum_param_names {
58 EPN_TEXT,
59 EPN_SEND,
60 EPN_FILE,
61 EPN_UPLOAD,
62 };
63
64 static int
file_upload_cb(void * data,const char * name,const char * filename,char * buf,int len,enum lws_spa_fileupload_states state)65 file_upload_cb(void *data, const char *name, const char *filename,
66 char *buf, int len, enum lws_spa_fileupload_states state)
67 {
68 struct per_session_data__post_demo *pss =
69 (struct per_session_data__post_demo *)data;
70 #if !defined(LWS_WITH_ESP32)
71 int n;
72
73 (void)n;
74 #endif
75
76 switch (state) {
77 case LWS_UFS_OPEN:
78 lws_strncpy(pss->filename, filename, sizeof(pss->filename));
79 /* we get the original filename in @filename arg, but for
80 * simple demo use a fixed name so we don't have to deal with
81 * attacks */
82 #if !defined(LWS_WITH_ESP32)
83 pss->fd = (lws_filefd_type)(long long)lws_open("/tmp/post-file",
84 O_CREAT | O_TRUNC | O_RDWR, 0600);
85 #endif
86 break;
87 case LWS_UFS_FINAL_CONTENT:
88 case LWS_UFS_CONTENT:
89 if (len) {
90 pss->file_length += len;
91
92 /* if the file length is too big, drop it */
93 if (pss->file_length > 100000)
94 return 1;
95
96 #if !defined(LWS_WITH_ESP32)
97 n = write((int)(long long)pss->fd, buf, len);
98 lwsl_info("%s: write %d says %d\n", __func__, len, n);
99 #else
100 lwsl_notice("%s: Received chunk size %d\n", __func__, len);
101 #endif
102 }
103 if (state == LWS_UFS_CONTENT)
104 break;
105 #if !defined(LWS_WITH_ESP32)
106 close((int)(long long)pss->fd);
107 pss->fd = LWS_INVALID_FILE;
108 #endif
109 break;
110 case LWS_UFS_CLOSE:
111 break;
112 }
113
114 return 0;
115 }
116
117 /*
118 * returns length in bytes
119 */
120
121 static int
format_result(struct per_session_data__post_demo * pss)122 format_result(struct per_session_data__post_demo *pss)
123 {
124 unsigned char *p, *start, *end;
125 int n;
126
127 p = (unsigned char *)pss->result + LWS_PRE;
128 start = p;
129 end = p + sizeof(pss->result) - LWS_PRE - 1;
130
131 p += lws_snprintf((char *)p, end -p,
132 "<!DOCTYPE html><html lang=\"en\"><head>"
133 "<meta charset=utf-8 http-equiv=\"Content-Language\" "
134 "content=\"en\"/>"
135 "<title>LWS Server Status</title>"
136 "</head><body><h1>Form results (after urldecoding)</h1>"
137 "<table><tr><td>Name</td><td>Length</td><td>Value</td></tr>");
138
139 for (n = 0; n < (int)LWS_ARRAY_SIZE(param_names); n++) {
140 if (!lws_spa_get_string(pss->spa, n))
141 p += lws_snprintf((char *)p, end - p,
142 "<tr><td><b>%s</b></td><td>0"
143 "</td><td>NULL</td></tr>",
144 param_names[n]);
145 else
146 p += lws_snprintf((char *)p, end - p,
147 "<tr><td><b>%s</b></td><td>%d"
148 "</td><td>%s</td></tr>",
149 param_names[n],
150 lws_spa_get_length(pss->spa, n),
151 lws_spa_get_string(pss->spa, n));
152 }
153
154 p += lws_snprintf((char *)p, end - p,
155 "</table><br><b>filename:</b> %s, "
156 "<b>length</b> %ld",
157 pss->filename, pss->file_length);
158
159 p += lws_snprintf((char *)p, end - p, "</body></html>");
160
161 return (int)lws_ptr_diff(p, start);
162 }
163
164 static int
callback_post_demo(struct lws * wsi,enum lws_callback_reasons reason,void * user,void * in,size_t len)165 callback_post_demo(struct lws *wsi, enum lws_callback_reasons reason,
166 void *user, void *in, size_t len)
167 {
168 struct per_session_data__post_demo *pss =
169 (struct per_session_data__post_demo *)user;
170 unsigned char *p, *start, *end;
171 int n;
172
173 switch (reason) {
174 case LWS_CALLBACK_HTTP_BODY:
175 /* create the POST argument parser if not already existing */
176 if (!pss->spa) {
177 pss->spa = lws_spa_create(wsi, param_names,
178 LWS_ARRAY_SIZE(param_names), 1024,
179 file_upload_cb, pss);
180 if (!pss->spa)
181 return -1;
182
183 pss->filename[0] = '\0';
184 pss->file_length = 0;
185 }
186
187 /* let it parse the POST data */
188 if (lws_spa_process(pss->spa, in, (int)len))
189 return -1;
190 break;
191
192 case LWS_CALLBACK_HTTP_BODY_COMPLETION:
193 lwsl_debug("LWS_CALLBACK_HTTP_BODY_COMPLETION: %p\n", wsi);
194 /* call to inform no more payload data coming */
195 lws_spa_finalize(pss->spa);
196
197 pss->completed = 1;
198 lws_callback_on_writable(wsi);
199 break;
200
201 case LWS_CALLBACK_HTTP_WRITEABLE:
202 if (!pss->completed)
203 break;
204
205 p = (unsigned char *)pss->result + LWS_PRE;
206 start = p;
207 end = p + sizeof(pss->result) - LWS_PRE - 1;
208
209 if (!pss->sent_headers) {
210 n = format_result(pss);
211
212 if (lws_add_http_header_status(wsi, HTTP_STATUS_OK,
213 &p, end))
214 goto bail;
215
216 if (lws_add_http_header_by_token(wsi,
217 WSI_TOKEN_HTTP_CONTENT_TYPE,
218 (unsigned char *)"text/html", 9,
219 &p, end))
220 goto bail;
221 if (lws_add_http_header_content_length(wsi, n, &p, end))
222 goto bail;
223 if (lws_finalize_http_header(wsi, &p, end))
224 goto bail;
225
226 /* first send the headers ... */
227 n = lws_write(wsi, start, lws_ptr_diff(p, start),
228 LWS_WRITE_HTTP_HEADERS);
229 if (n < 0)
230 goto bail;
231
232 pss->sent_headers = 1;
233 lws_callback_on_writable(wsi);
234 break;
235 }
236
237 if (!pss->sent_body) {
238 n = format_result(pss);
239
240 n = lws_write(wsi, (unsigned char *)start, n,
241 LWS_WRITE_HTTP_FINAL);
242
243 pss->sent_body = 1;
244 if (n < 0)
245 return 1;
246 goto try_to_reuse;
247 }
248 break;
249
250 case LWS_CALLBACK_HTTP_DROP_PROTOCOL:
251 /* called when our wsi user_space is going to be destroyed */
252 if (pss->spa) {
253 lws_spa_destroy(pss->spa);
254 pss->spa = NULL;
255 }
256 break;
257
258 default:
259 break;
260 }
261
262 return 0;
263
264 bail:
265
266 return 1;
267
268 try_to_reuse:
269 if (lws_http_transaction_completed(wsi))
270 return -1;
271
272 return 0;
273 }
274
275 #define LWS_PLUGIN_PROTOCOL_POST_DEMO \
276 { \
277 "protocol-post-demo", \
278 callback_post_demo, \
279 sizeof(struct per_session_data__post_demo), \
280 1024, \
281 0, NULL, 0 \
282 }
283
284 #if !defined (LWS_PLUGIN_STATIC)
285
286 static const struct lws_protocols protocols[] = {
287 LWS_PLUGIN_PROTOCOL_POST_DEMO
288 };
289
290 LWS_VISIBLE int
init_protocol_post_demo(struct lws_context * context,struct lws_plugin_capability * c)291 init_protocol_post_demo(struct lws_context *context,
292 struct lws_plugin_capability *c)
293 {
294 if (c->api_magic != LWS_PLUGIN_API_MAGIC) {
295 lwsl_err("Plugin API %d, library API %d", LWS_PLUGIN_API_MAGIC,
296 c->api_magic);
297 return 1;
298 }
299
300 c->protocols = protocols;
301 c->count_protocols = LWS_ARRAY_SIZE(protocols);
302 c->extensions = NULL;
303 c->count_extensions = 0;
304
305 return 0;
306 }
307
308 LWS_VISIBLE int
destroy_protocol_post_demo(struct lws_context * context)309 destroy_protocol_post_demo(struct lws_context *context)
310 {
311 return 0;
312 }
313
314 #endif
315