xref: /lighttpd1.4/src/mod_scgi.c (revision 66698469)
1 #include "first.h"
2 
3 #include <sys/types.h>
4 #include <limits.h>
5 #include <stdlib.h>
6 #include <string.h>
7 
8 #include "gw_backend.h"
9 typedef gw_plugin_config plugin_config;
10 typedef gw_plugin_data   plugin_data;
11 typedef gw_handler_ctx   handler_ctx;
12 
13 #include "base.h"
14 #include "buffer.h"
15 #include "http_cgi.h"
16 #include "log.h"
17 #include "status_counter.h"
18 
19 enum { LI_PROTOCOL_SCGI, LI_PROTOCOL_UWSGI };
20 
21 static void mod_scgi_merge_config_cpv(plugin_config * const pconf, const config_plugin_value_t * const cpv) {
22     switch (cpv->k_id) { /* index into static config_plugin_keys_t cpk[] */
23       case 0: /* scgi.server */
24         if (cpv->vtype == T_CONFIG_LOCAL) {
25             gw_plugin_config * const gw = cpv->v.v;
26             pconf->exts      = gw->exts;
27             pconf->exts_auth = gw->exts_auth;
28             pconf->exts_resp = gw->exts_resp;
29         }
30         break;
31       case 1: /* scgi.balance */
32         /*if (cpv->vtype == T_CONFIG_LOCAL)*//*always true here for this param*/
33             pconf->balance = (int)cpv->v.u;
34         break;
35       case 2: /* scgi.debug */
36         pconf->debug = (int)cpv->v.u;
37         break;
38       case 3: /* scgi.map-extensions */
39         pconf->ext_mapping = cpv->v.a;
40         break;
41       case 4: /* scgi.protocol */
42         /*if (cpv->vtype == T_CONFIG_LOCAL)*//*always true here for this param*/
43             pconf->proto = (int)cpv->v.u;
44         break;
45       default:/* should not happen */
46         return;
47     }
48 }
49 
50 static void mod_scgi_merge_config(plugin_config * const pconf, const config_plugin_value_t *cpv) {
51     do {
52         mod_scgi_merge_config_cpv(pconf, cpv);
53     } while ((++cpv)->k_id != -1);
54 }
55 
56 static void mod_scgi_patch_config(request_st * const r, plugin_data * const p) {
57     memcpy(&p->conf, &p->defaults, sizeof(plugin_config));
58     for (int i = 1, used = p->nconfig; i < used; ++i) {
59         if (config_check_cond(r, (uint32_t)p->cvlist[i].k_id))
60             mod_scgi_merge_config(&p->conf, p->cvlist + p->cvlist[i].v.u2[0]);
61     }
62 }
63 
64 SETDEFAULTS_FUNC(mod_scgi_set_defaults) {
65     static const config_plugin_keys_t cpk[] = {
66       { CONST_STR_LEN("scgi.server"),
67         T_CONFIG_ARRAY_KVARRAY,
68         T_CONFIG_SCOPE_CONNECTION }
69      ,{ CONST_STR_LEN("scgi.balance"),
70         T_CONFIG_STRING,
71         T_CONFIG_SCOPE_CONNECTION }
72      ,{ CONST_STR_LEN("scgi.debug"),
73         T_CONFIG_INT,
74         T_CONFIG_SCOPE_CONNECTION }
75      ,{ CONST_STR_LEN("scgi.map-extensions"),
76         T_CONFIG_ARRAY_KVSTRING,
77         T_CONFIG_SCOPE_CONNECTION }
78      ,{ CONST_STR_LEN("scgi.protocol"),
79         T_CONFIG_STRING,
80         T_CONFIG_SCOPE_CONNECTION }
81      ,{ NULL, 0,
82         T_CONFIG_UNSET,
83         T_CONFIG_SCOPE_UNSET }
84     };
85 
86     plugin_data * const p = p_d;
87     if (!config_plugin_values_init(srv, p, cpk, "mod_scgi"))
88         return HANDLER_ERROR;
89 
90     /* process and validate config directives
91      * (init i to 0 if global context; to 1 to skip empty global context) */
92     for (int i = !p->cvlist[0].v.u2[1]; i < p->nconfig; ++i) {
93         config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0];
94         for (; -1 != cpv->k_id; ++cpv) {
95             switch (cpv->k_id) {
96               case 0:{/* scgi.server */
97                 gw_plugin_config *gw = calloc(1, sizeof(gw_plugin_config));
98                 force_assert(gw);
99                 if (!gw_set_defaults_backend(srv, p, cpv->v.a, gw, 1,
100                                              cpk[cpv->k_id].k)) {
101                     gw_plugin_config_free(gw);
102                     return HANDLER_ERROR;
103                 }
104                 cpv->v.v = gw;
105                 cpv->vtype = T_CONFIG_LOCAL;
106                 break;
107               }
108               case 1: /* scgi.balance */
109                 cpv->v.u = (unsigned int)gw_get_defaults_balance(srv, cpv->v.b);
110                 break;
111               case 2: /* scgi.debug */
112               case 3: /* scgi.map-extensions */
113                 break;
114               case 4: /* scgi.protocol */
115                 if (buffer_eq_slen(cpv->v.b, CONST_STR_LEN("scgi")))
116                     cpv->v.u = LI_PROTOCOL_SCGI;
117                 else if (buffer_eq_slen(cpv->v.b, CONST_STR_LEN("uwsgi")))
118                     cpv->v.u = LI_PROTOCOL_UWSGI;
119                 else {
120                     log_error(srv->errh, __FILE__, __LINE__,
121                       "unexpected type for key: %s"
122                       "expected \"scgi\" or \"uwsgi\"", cpk[cpv->k_id].k);
123                     return HANDLER_ERROR;
124                 }
125                 break;
126               default:/* should not happen */
127                 break;
128             }
129         }
130     }
131 
132     /* default is 0 */
133     /*p->defaults.balance = (unsigned int)gw_get_defaults_balance(srv, NULL);*/
134     /*p->defaults.proto   = LI_PROTOCOL_SCGI;*//*(default)*/
135 
136     /* initialize p->defaults from global config context */
137     if (p->nconfig > 0 && p->cvlist->v.u2[1]) {
138         const config_plugin_value_t *cpv = p->cvlist + p->cvlist->v.u2[0];
139         if (-1 != cpv->k_id)
140             mod_scgi_merge_config(&p->defaults, cpv);
141     }
142 
143     return HANDLER_GO_ON;
144 }
145 
146 static int scgi_env_add_scgi(void *venv, const char *key, size_t key_len, const char *val, size_t val_len) {
147 	buffer *env = venv;
148 	size_t len;
149 
150 	if (!key || (!val && val_len)) return -1;
151 
152 	len = key_len + val_len + 2;
153 
154 	char *dst = buffer_extend(env, len);
155 	memcpy(dst, key, key_len);
156 	dst[key_len] = '\0';
157 	dst += key_len + 1;
158 	memcpy(dst, val, val_len);
159 	dst[val_len] = '\0';
160 
161 	return 0;
162 }
163 
164 
165 static int scgi_env_add_uwsgi(void *venv, const char *key, size_t key_len, const char *val, size_t val_len) {
166 	if (!key || (!val && val_len)) return -1;
167 	if (key_len > USHRT_MAX || val_len > USHRT_MAX) return -1;
168 
169 	char *dst = buffer_extend(venv, 2 + key_len + 2 + val_len);
170 	dst[0] =  key_len       & 0xff; /* little-endian */
171 	dst[1] = (key_len >> 8) & 0xff;
172 	memcpy(dst + 2, key, key_len);
173 	dst += 2+key_len;
174 	dst[0] =  val_len       & 0xff; /* little-endian */
175 	dst[1] = (val_len >> 8) & 0xff;
176 	memcpy(dst + 2, val, val_len);
177 
178 	return 0;
179 }
180 
181 
182 static handler_t scgi_create_env(handler_ctx *hctx) {
183 	gw_host *host = hctx->host;
184 	request_st * const r = hctx->r;
185 	http_cgi_opts opts = { 0, 0, host->docroot, NULL };
186 	http_cgi_header_append_cb scgi_env_add = hctx->conf.proto == LI_PROTOCOL_SCGI
187 	  ? scgi_env_add_scgi
188 	  : scgi_env_add_uwsgi;
189 	size_t offset;
190 	size_t rsz = (size_t)(r->read_queue.bytes_out - hctx->wb.bytes_in);
191 	if (rsz >= 65536) rsz = r->rqst_header_len;
192 	buffer * const b = chunkqueue_prepend_buffer_open_sz(&hctx->wb, rsz);
193 
194         /* save space for 9 digits (plus ':'), though incoming HTTP request
195 	 * currently limited to 64k (65535, so 5 chars) */
196 	buffer_copy_string_len(b, CONST_STR_LEN("          "));
197 
198 	if (0 != http_cgi_headers(r, &opts, scgi_env_add, b)) {
199 		r->http_status = 400;
200 		r->handler_module = NULL;
201 		buffer_clear(b);
202 		chunkqueue_remove_finished_chunks(&hctx->wb);
203 		return HANDLER_FINISHED;
204 	}
205 
206 	if (hctx->conf.proto == LI_PROTOCOL_SCGI) {
207 		buffer * const tb = r->tmp_buf;
208 		size_t len;
209 		scgi_env_add(b, CONST_STR_LEN("SCGI"), CONST_STR_LEN("1"));
210 		buffer_clear(tb);
211 		buffer_append_int(tb, buffer_clen(b)-10);
212 		buffer_append_char(tb, ':');
213 		len = buffer_clen(tb);
214 		offset = 10 - len;
215 		memcpy(b->ptr+offset, tb->ptr, len);
216 		buffer_append_char(b, ',');
217 	} else { /* LI_PROTOCOL_UWSGI */
218 		/* http://uwsgi-docs.readthedocs.io/en/latest/Protocol.html */
219 		size_t len = buffer_clen(b)-10;
220 		if (len > USHRT_MAX) {
221 			r->http_status = 431; /* Request Header Fields Too Large */
222 			r->handler_module = NULL;
223 			buffer_clear(b);
224 			chunkqueue_remove_finished_chunks(&hctx->wb);
225 			return HANDLER_FINISHED;
226 		}
227 		offset = 10 - 4;
228 		b->ptr[offset]   = 0;
229 		b->ptr[offset+1] =  len       & 0xff; /* little-endian */
230 		b->ptr[offset+2] = (len >> 8) & 0xff;
231 		b->ptr[offset+3] = 0;
232 	}
233 
234 	hctx->wb_reqlen = buffer_clen(b) - offset;
235 	chunkqueue_prepend_buffer_commit(&hctx->wb);
236 	chunkqueue_mark_written(&hctx->wb, offset);
237 	hctx->wb.bytes_in  -= (off_t)offset;
238 	hctx->wb.bytes_out -= (off_t)offset;
239 
240 	if (r->reqbody_length) {
241 		chunkqueue_append_chunkqueue(&hctx->wb, &r->reqbody_queue);
242 		if (r->reqbody_length > 0)
243 			hctx->wb_reqlen += r->reqbody_length; /* total req size */
244 		else /* as-yet-unknown total request size (Transfer-Encoding: chunked)*/
245 			hctx->wb_reqlen = -hctx->wb_reqlen;
246 	}
247 
248 	status_counter_inc(CONST_STR_LEN("scgi.requests"));
249 	return HANDLER_GO_ON;
250 }
251 
252 
253 static handler_t scgi_check_extension(request_st * const r, void *p_d, int uri_path_handler) {
254 	plugin_data *p = p_d;
255 	handler_t rc;
256 
257 	if (NULL != r->handler_module) return HANDLER_GO_ON;
258 
259 	mod_scgi_patch_config(r, p);
260 	if (NULL == p->conf.exts) return HANDLER_GO_ON;
261 
262 	rc = gw_check_extension(r, p, uri_path_handler, 0);
263 	if (HANDLER_GO_ON != rc) return rc;
264 
265 	if (r->handler_module == p->self) {
266 		handler_ctx *hctx = r->plugin_ctx[p->id];
267 		hctx->opts.backend = BACKEND_SCGI;
268 		hctx->create_env = scgi_create_env;
269 		hctx->response = chunk_buffer_acquire();
270 	}
271 
272 	return HANDLER_GO_ON;
273 }
274 
275 /* uri-path handler */
276 static handler_t scgi_check_extension_1(request_st * const r, void *p_d) {
277 	return scgi_check_extension(r, p_d, 1);
278 }
279 
280 /* start request handler */
281 static handler_t scgi_check_extension_2(request_st * const r, void *p_d) {
282 	return scgi_check_extension(r, p_d, 0);
283 }
284 
285 
286 
287 int mod_scgi_plugin_init(plugin *p);
288 int mod_scgi_plugin_init(plugin *p) {
289 	p->version     = LIGHTTPD_VERSION_ID;
290 	p->name         = "scgi";
291 
292 	p->init         = gw_init;
293 	p->cleanup      = gw_free;
294 	p->set_defaults = mod_scgi_set_defaults;
295 	p->handle_request_reset    = gw_handle_request_reset;
296 	p->handle_uri_clean        = scgi_check_extension_1;
297 	p->handle_subrequest_start = scgi_check_extension_2;
298 	p->handle_subrequest       = gw_handle_subrequest;
299 	p->handle_trigger          = gw_handle_trigger;
300 	p->handle_waitpid          = gw_handle_waitpid_cb;
301 
302 	return 0;
303 }
304