xref: /lighttpd1.4/src/mod_scgi.c (revision 5e14db43)
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 
18 enum { LI_PROTOCOL_SCGI, LI_PROTOCOL_UWSGI };
19 
mod_scgi_merge_config_cpv(plugin_config * const pconf,const config_plugin_value_t * const cpv)20 static void mod_scgi_merge_config_cpv(plugin_config * const pconf, const config_plugin_value_t * const cpv) {
21     switch (cpv->k_id) { /* index into static config_plugin_keys_t cpk[] */
22       case 0: /* scgi.server */
23         if (cpv->vtype == T_CONFIG_LOCAL) {
24             gw_plugin_config * const gw = cpv->v.v;
25             pconf->exts      = gw->exts;
26             pconf->exts_auth = gw->exts_auth;
27             pconf->exts_resp = gw->exts_resp;
28         }
29         break;
30       case 1: /* scgi.balance */
31         /*if (cpv->vtype == T_CONFIG_LOCAL)*//*always true here for this param*/
32             pconf->balance = (int)cpv->v.u;
33         break;
34       case 2: /* scgi.debug */
35         pconf->debug = (int)cpv->v.u;
36         break;
37       case 3: /* scgi.map-extensions */
38         pconf->ext_mapping = cpv->v.a;
39         break;
40       case 4: /* scgi.protocol */
41         /*if (cpv->vtype == T_CONFIG_LOCAL)*//*always true here for this param*/
42             pconf->proto = (int)cpv->v.u;
43         break;
44       default:/* should not happen */
45         return;
46     }
47 }
48 
mod_scgi_merge_config(plugin_config * const pconf,const config_plugin_value_t * cpv)49 static void mod_scgi_merge_config(plugin_config * const pconf, const config_plugin_value_t *cpv) {
50     do {
51         mod_scgi_merge_config_cpv(pconf, cpv);
52     } while ((++cpv)->k_id != -1);
53 }
54 
mod_scgi_patch_config(request_st * const r,plugin_data * const p)55 static void mod_scgi_patch_config(request_st * const r, plugin_data * const p) {
56     memcpy(&p->conf, &p->defaults, sizeof(plugin_config));
57     for (int i = 1, used = p->nconfig; i < used; ++i) {
58         if (config_check_cond(r, (uint32_t)p->cvlist[i].k_id))
59             mod_scgi_merge_config(&p->conf, p->cvlist + p->cvlist[i].v.u2[0]);
60     }
61 }
62 
SETDEFAULTS_FUNC(mod_scgi_set_defaults)63 SETDEFAULTS_FUNC(mod_scgi_set_defaults) {
64     static const config_plugin_keys_t cpk[] = {
65       { CONST_STR_LEN("scgi.server"),
66         T_CONFIG_ARRAY_KVARRAY,
67         T_CONFIG_SCOPE_CONNECTION }
68      ,{ CONST_STR_LEN("scgi.balance"),
69         T_CONFIG_STRING,
70         T_CONFIG_SCOPE_CONNECTION }
71      ,{ CONST_STR_LEN("scgi.debug"),
72         T_CONFIG_INT,
73         T_CONFIG_SCOPE_CONNECTION }
74      ,{ CONST_STR_LEN("scgi.map-extensions"),
75         T_CONFIG_ARRAY_KVSTRING,
76         T_CONFIG_SCOPE_CONNECTION }
77      ,{ CONST_STR_LEN("scgi.protocol"),
78         T_CONFIG_STRING,
79         T_CONFIG_SCOPE_CONNECTION }
80      ,{ NULL, 0,
81         T_CONFIG_UNSET,
82         T_CONFIG_SCOPE_UNSET }
83     };
84 
85     plugin_data * const p = p_d;
86     if (!config_plugin_values_init(srv, p, cpk, "mod_scgi"))
87         return HANDLER_ERROR;
88 
89     /* process and validate config directives
90      * (init i to 0 if global context; to 1 to skip empty global context) */
91     for (int i = !p->cvlist[0].v.u2[1]; i < p->nconfig; ++i) {
92         config_plugin_value_t *cpv = p->cvlist + p->cvlist[i].v.u2[0];
93         for (; -1 != cpv->k_id; ++cpv) {
94             switch (cpv->k_id) {
95               case 0:{/* scgi.server */
96                 gw_plugin_config *gw = ck_calloc(1, sizeof(gw_plugin_config));
97                 if (!gw_set_defaults_backend(srv, p, cpv->v.a, gw, 1,
98                                              cpk[cpv->k_id].k)) {
99                     gw_plugin_config_free(gw);
100                     return HANDLER_ERROR;
101                 }
102                 cpv->v.v = gw;
103                 cpv->vtype = T_CONFIG_LOCAL;
104                 break;
105               }
106               case 1: /* scgi.balance */
107                 cpv->v.u = (unsigned int)gw_get_defaults_balance(srv, cpv->v.b);
108                 break;
109               case 2: /* scgi.debug */
110               case 3: /* scgi.map-extensions */
111                 break;
112               case 4: /* scgi.protocol */
113                 if (buffer_eq_slen(cpv->v.b, CONST_STR_LEN("scgi")))
114                     cpv->v.u = LI_PROTOCOL_SCGI;
115                 else if (buffer_eq_slen(cpv->v.b, CONST_STR_LEN("uwsgi")))
116                     cpv->v.u = LI_PROTOCOL_UWSGI;
117                 else {
118                     log_error(srv->errh, __FILE__, __LINE__,
119                       "unexpected type for key: %s"
120                       "expected \"scgi\" or \"uwsgi\"", cpk[cpv->k_id].k);
121                     return HANDLER_ERROR;
122                 }
123                 break;
124               default:/* should not happen */
125                 break;
126             }
127         }
128     }
129 
130     /* default is 0 */
131     /*p->defaults.balance = (unsigned int)gw_get_defaults_balance(srv, NULL);*/
132     /*p->defaults.proto   = LI_PROTOCOL_SCGI;*//*(default)*/
133 
134     /* initialize p->defaults from global config context */
135     if (p->nconfig > 0 && p->cvlist->v.u2[1]) {
136         const config_plugin_value_t *cpv = p->cvlist + p->cvlist->v.u2[0];
137         if (-1 != cpv->k_id)
138             mod_scgi_merge_config(&p->defaults, cpv);
139     }
140 
141     return HANDLER_GO_ON;
142 }
143 
scgi_env_add_scgi(void * venv,const char * key,size_t key_len,const char * val,size_t val_len)144 static int scgi_env_add_scgi(void *venv, const char *key, size_t key_len, const char *val, size_t val_len) {
145 	buffer *env = venv;
146 	size_t len;
147 
148 	if (!key || (!val && val_len)) return -1;
149 
150 	len = key_len + val_len + 2;
151 
152 	char *dst = buffer_extend(env, len);
153 	memcpy(dst, key, key_len);
154 	dst[key_len] = '\0';
155 	dst += key_len + 1;
156 	memcpy(dst, val, val_len);
157 	dst[val_len] = '\0';
158 
159 	return 0;
160 }
161 
162 
scgi_env_add_uwsgi(void * venv,const char * key,size_t key_len,const char * val,size_t val_len)163 static int scgi_env_add_uwsgi(void *venv, const char *key, size_t key_len, const char *val, size_t val_len) {
164 	if (!key || (!val && val_len)) return -1;
165 	if (key_len > USHRT_MAX || val_len > USHRT_MAX) return -1;
166 
167 	char *dst = buffer_extend(venv, 2 + key_len + 2 + val_len);
168 	dst[0] =  key_len       & 0xff; /* little-endian */
169 	dst[1] = (key_len >> 8) & 0xff;
170 	memcpy(dst + 2, key, key_len);
171 	dst += 2+key_len;
172 	dst[0] =  val_len       & 0xff; /* little-endian */
173 	dst[1] = (val_len >> 8) & 0xff;
174 	memcpy(dst + 2, val, val_len);
175 
176 	return 0;
177 }
178 
179 
scgi_create_env(handler_ctx * hctx)180 static handler_t scgi_create_env(handler_ctx *hctx) {
181 	gw_host *host = hctx->host;
182 	request_st * const r = hctx->r;
183 	http_cgi_opts opts = { 0, 0, host->docroot, NULL };
184 	http_cgi_header_append_cb scgi_env_add = hctx->conf.proto == LI_PROTOCOL_SCGI
185 	  ? scgi_env_add_scgi
186 	  : scgi_env_add_uwsgi;
187 	size_t offset;
188 	size_t rsz = (size_t)(r->read_queue.bytes_out - hctx->wb.bytes_in);
189 	if (rsz >= 65536) rsz = r->rqst_header_len;
190 	buffer * const b = chunkqueue_prepend_buffer_open_sz(&hctx->wb, rsz);
191 
192         /* save space for 9 digits (plus ':'), though incoming HTTP request
193 	 * currently limited to 64k (65535, so 5 chars) */
194 	buffer_copy_string_len(b, CONST_STR_LEN("          "));
195 
196 	if (0 != http_cgi_headers(r, &opts, scgi_env_add, b)) {
197 		r->http_status = 400;
198 		r->handler_module = NULL;
199 		buffer_clear(b);
200 		chunkqueue_remove_finished_chunks(&hctx->wb);
201 		return HANDLER_FINISHED;
202 	}
203 
204 	if (hctx->conf.proto == LI_PROTOCOL_SCGI) {
205 		buffer * const tb = r->tmp_buf;
206 		size_t len;
207 		scgi_env_add(b, CONST_STR_LEN("SCGI"), CONST_STR_LEN("1"));
208 		buffer_clear(tb);
209 		buffer_append_int(tb, buffer_clen(b)-10);
210 		buffer_append_char(tb, ':');
211 		len = buffer_clen(tb);
212 		offset = 10 - len;
213 		memcpy(b->ptr+offset, tb->ptr, len);
214 		buffer_append_char(b, ',');
215 	} else { /* LI_PROTOCOL_UWSGI */
216 		/* http://uwsgi-docs.readthedocs.io/en/latest/Protocol.html */
217 		size_t len = buffer_clen(b)-10;
218 		if (len > USHRT_MAX) {
219 			r->http_status = 431; /* Request Header Fields Too Large */
220 			r->handler_module = NULL;
221 			buffer_clear(b);
222 			chunkqueue_remove_finished_chunks(&hctx->wb);
223 			return HANDLER_FINISHED;
224 		}
225 		offset = 10 - 4;
226 		b->ptr[offset]   = 0;
227 		b->ptr[offset+1] =  len       & 0xff; /* little-endian */
228 		b->ptr[offset+2] = (len >> 8) & 0xff;
229 		b->ptr[offset+3] = 0;
230 	}
231 
232 	hctx->wb_reqlen = buffer_clen(b) - offset;
233 	chunkqueue_prepend_buffer_commit(&hctx->wb);
234 	chunkqueue_mark_written(&hctx->wb, offset);
235 	hctx->wb.bytes_in  -= (off_t)offset;
236 	hctx->wb.bytes_out -= (off_t)offset;
237 
238 	if (r->reqbody_length) {
239 		chunkqueue_append_chunkqueue(&hctx->wb, &r->reqbody_queue);
240 		if (r->reqbody_length > 0)
241 			hctx->wb_reqlen += r->reqbody_length; /* total req size */
242 		else /* as-yet-unknown total request size (Transfer-Encoding: chunked)*/
243 			hctx->wb_reqlen = -hctx->wb_reqlen;
244 	}
245 
246 	plugin_stats_inc("scgi.requests");
247 	return HANDLER_GO_ON;
248 }
249 
250 
scgi_check_extension(request_st * const r,void * p_d,int uri_path_handler)251 static handler_t scgi_check_extension(request_st * const r, void *p_d, int uri_path_handler) {
252 	plugin_data *p = p_d;
253 	handler_t rc;
254 
255 	if (NULL != r->handler_module) return HANDLER_GO_ON;
256 
257 	mod_scgi_patch_config(r, p);
258 	if (NULL == p->conf.exts) return HANDLER_GO_ON;
259 
260 	rc = gw_check_extension(r, p, uri_path_handler, 0);
261 	if (HANDLER_GO_ON != rc) return rc;
262 
263 	if (r->handler_module == p->self) {
264 		handler_ctx *hctx = r->plugin_ctx[p->id];
265 		hctx->opts.backend = BACKEND_SCGI;
266 		hctx->create_env = scgi_create_env;
267 		hctx->response = chunk_buffer_acquire();
268 	}
269 
270 	return HANDLER_GO_ON;
271 }
272 
273 /* uri-path handler */
scgi_check_extension_1(request_st * const r,void * p_d)274 static handler_t scgi_check_extension_1(request_st * const r, void *p_d) {
275 	return scgi_check_extension(r, p_d, 1);
276 }
277 
278 /* start request handler */
scgi_check_extension_2(request_st * const r,void * p_d)279 static handler_t scgi_check_extension_2(request_st * const r, void *p_d) {
280 	return scgi_check_extension(r, p_d, 0);
281 }
282 
283 
284 __attribute_cold__
285 int mod_scgi_plugin_init(plugin *p);
mod_scgi_plugin_init(plugin * p)286 int mod_scgi_plugin_init(plugin *p) {
287 	p->version     = LIGHTTPD_VERSION_ID;
288 	p->name         = "scgi";
289 
290 	p->init         = gw_init;
291 	p->cleanup      = gw_free;
292 	p->set_defaults = mod_scgi_set_defaults;
293 	p->handle_request_reset    = gw_handle_request_reset;
294 	p->handle_uri_clean        = scgi_check_extension_1;
295 	p->handle_subrequest_start = scgi_check_extension_2;
296 	p->handle_subrequest       = gw_handle_subrequest;
297 	p->handle_trigger          = gw_handle_trigger;
298 	p->handle_waitpid          = gw_handle_waitpid_cb;
299 
300 	return 0;
301 }
302