proc.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd
   3  *
   4  *   Copyright (C) 2010-2012 Jo-Philipp Wich <xm@subsignal.org>
   5  *   Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  *  Licensed under the Apache License, Version 2.0 (the "License");
   8  *  you may not use this file except in compliance with the License.
   9  *  You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  *  Unless required by applicable law or agreed to in writing, software
  14  *  distributed under the License is distributed on an "AS IS" BASIS,
  15  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  *  See the License for the specific language governing permissions and
  17  *  limitations under the License.
  18  */
  19
  20 #include <libubox/blobmsg.h>
  21 #include "uhttpd.h"
  22
  23 #define __headers \
  24         __header(accept) \
  25         __header(accept_charset) \
  26         __header(accept_encoding) \
  27         __header(accept_language) \
  28         __header(authorization) \
  29         __header(connection) \
  30         __header(cookie) \
  31         __header(host) \
  32         __header(referer) \
  33         __header(user_agent) \
  34         __header(content_type) \
  35         __header(content_length)
  36
  37 #undef __header
  38 #define __header __enum_header
  39 enum client_hdr {
  40         __headers
  41         __HDR_MAX,
  42 };
  43
  44 #undef __header
  45 #define __header __blobmsg_header
  46 static const struct blobmsg_policy hdr_policy[__HDR_MAX] = {
  47         __headers
  48 };
  49
  50 static const struct {
  51         const char *name;
  52         int idx;
  53 } proc_header_env[] = {
  54         { "HTTP_ACCEPT", HDR_accept },
  55         { "HTTP_ACCEPT_CHARSET", HDR_accept_charset },
  56         { "HTTP_ACCEPT_ENCODING", HDR_accept_encoding },
  57         { "HTTP_ACCEPT_LANGUAGE", HDR_accept_language },
  58         { "HTTP_AUTHORIZATION", HDR_authorization },
  59         { "HTTP_CONNECTION", HDR_connection },
  60         { "HTTP_COOKIE", HDR_cookie },
  61         { "HTTP_HOST", HDR_host },
  62         { "HTTP_REFERER", HDR_referer },
  63         { "HTTP_USER_AGENT", HDR_user_agent },
  64         { "CONTENT_TYPE", HDR_content_type },
  65         { "CONTENT_LENGTH", HDR_content_length },
  66 };
  67
  68 enum extra_vars {
  69         /* no update needed */
  70         _VAR_GW,
  71         _VAR_SOFTWARE,
  72
  73         /* updated by uh_get_process_vars */
  74         VAR_SCRIPT_NAME,
  75         VAR_SCRIPT_FILE,
  76         VAR_DOCROOT,
  77         VAR_QUERY,
  78         VAR_REQUEST,
  79         VAR_PROTO,
  80         VAR_METHOD,
  81         VAR_PATH_INFO,
  82         VAR_USER,
  83         VAR_REDIRECT,
  84
  85         __VAR_MAX,
  86 };
  87
  88 static struct env_var extra_vars[] = {
  89         [_VAR_GW] = { "GATEWAY_INTERFACE", "CGI/1.1" },
  90         [_VAR_SOFTWARE] = { "SERVER_SOFTWARE", "uhttpd" },
  91         [VAR_SCRIPT_NAME] = { "SCRIPT_NAME" },
  92         [VAR_SCRIPT_FILE] = { "SCRIPT_FILENAME" },
  93         [VAR_DOCROOT] = { "DOCUMENT_ROOT" },
  94         [VAR_QUERY] = { "QUERY_STRING" },
  95         [VAR_REQUEST] = { "REQUEST_URI" },
  96         [VAR_PROTO] = { "SERVER_PROTOCOL" },
  97         [VAR_METHOD] = { "REQUEST_METHOD" },
  98         [VAR_PATH_INFO] = { "PATH_INFO" },
  99         [VAR_USER] = { "REMOTE_USER" },
 100         [VAR_REDIRECT] = { "REDIRECT_STATUS" },
 101 };
 102
 103 struct env_var *uh_get_process_vars(struct client *cl, struct path_info *pi)
 104 {
 105         struct http_request *req = &cl->request;
 106         struct blob_attr *data = cl->hdr.head;
 107         struct env_var *vars = (void *) uh_buf;
 108         struct blob_attr *tb[__HDR_MAX];
 109         static char buf[4];
 110         int len;
 111         int i;
 112
 113         len = ARRAY_SIZE(proc_header_env);
 114         len += ARRAY_SIZE(extra_vars);
 115         len *= sizeof(struct env_var);
 116
 117         BUILD_BUG_ON(sizeof(uh_buf) < len);
 118
 119         extra_vars[VAR_SCRIPT_NAME].value = pi->name;
 120         extra_vars[VAR_SCRIPT_FILE].value = pi->phys;
 121         extra_vars[VAR_DOCROOT].value = pi->root;
 122         extra_vars[VAR_QUERY].value = pi->query ? pi->query : "";
 123         extra_vars[VAR_REQUEST].value = req->url;
 124         extra_vars[VAR_PROTO].value = http_versions[req->version];
 125         extra_vars[VAR_METHOD].value = http_methods[req->method];
 126         extra_vars[VAR_PATH_INFO].value = pi->info;
 127         extra_vars[VAR_USER].value = req->realm ? req->realm->user : NULL;
 128
 129         snprintf(buf, sizeof(buf), "%d", req->redirect_status);
 130         extra_vars[VAR_REDIRECT].value = buf;
 131
 132         blobmsg_parse(hdr_policy, __HDR_MAX, tb, blob_data(data), blob_len(data));
 133         for (i = 0; i < ARRAY_SIZE(proc_header_env); i++) {
 134                 struct blob_attr *cur;
 135
 136                 cur = tb[proc_header_env[i].idx];
 137                 vars[i].name = proc_header_env[i].name;
 138                 vars[i].value = cur ? blobmsg_data(cur) : "";
 139         }
 140
 141         memcpy(&vars[i], extra_vars, sizeof(extra_vars));
 142         i += ARRAY_SIZE(extra_vars);
 143         vars[i].name = NULL;
 144         vars[i].value = NULL;
 145
 146         return vars;
 147 }
 148
 149 static void proc_close_fds(struct client *cl)
 150 {
 151         close(cl->dispatch.proc.r.sfd.fd.fd);
 152 }
 153
 154 static void proc_handle_close(struct relay *r, int ret)
 155 {
 156         if (r->header_cb) {
 157                 uh_client_error(r->cl, 502, "Bad Gateway",
 158                                 "The process did not produce any response");
 159                 return;
 160         }
 161
 162         uh_request_done(r->cl);
 163 }
 164
 165 static void proc_handle_header(struct relay *r, const char *name, const char *val)
 166 {
 167         static char status_buf[64];
 168         struct client *cl = r->cl;
 169         char *sep;
 170         char buf[4];
 171
 172         if (!strcmp(name, "Status")) {
 173                 sep = strchr(val, ' ');
 174                 if (sep != val + 3)
 175                         return;
 176
 177                 memcpy(buf, val, 3);
 178                 buf[3] = 0;
 179                 snprintf(status_buf, sizeof(status_buf), "%s", sep + 1);
 180                 cl->dispatch.proc.status_msg = status_buf;
 181                 cl->dispatch.proc.status_code = atoi(buf);
 182                 return;
 183         }
 184
 185         blobmsg_add_string(&cl->dispatch.proc.hdr, name, val);
 186 }
 187
 188 static void proc_handle_header_end(struct relay *r)
 189 {
 190         struct client *cl = r->cl;
 191         struct blob_attr *cur;
 192         int rem;
 193
 194         uh_http_header(cl, cl->dispatch.proc.status_code, cl->dispatch.proc.status_msg);
 195         blob_for_each_attr(cur, cl->dispatch.proc.hdr.head, rem)
 196                 ustream_printf(cl->us, "%s: %s\r\n", blobmsg_name(cur), blobmsg_data(cur));
 197
 198         ustream_printf(cl->us, "\r\n");
 199 }
 200
 201 static void proc_free(struct client *cl)
 202 {
 203         uh_relay_free(&cl->dispatch.proc.r);
 204 }
 205
 206 bool uh_create_process(struct client *cl, struct path_info *pi,
 207                        void (*cb)(struct client *cl, struct path_info *pi, int fd))
 208 {
 209         int fds[2];
 210         int pid;
 211
 212         blob_buf_init(&cl->dispatch.proc.hdr, 0);
 213         cl->dispatch.proc.status_code = 200;
 214         cl->dispatch.proc.status_msg = "OK";
 215
 216         if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds))
 217                 return false;
 218
 219         pid = fork();
 220         if (pid < 0) {
 221                 close(fds[0]);
 222                 close(fds[1]);
 223                 return false;
 224         }
 225
 226         if (!pid) {
 227                 close(fds[0]);
 228                 uh_close_fds();
 229                 cb(cl, pi, fds[1]);
 230                 exit(0);
 231         }
 232
 233         close(fds[1]);
 234         uh_relay_open(cl, &cl->dispatch.proc.r, fds[0], pid);
 235         cl->dispatch.free = proc_free;
 236         cl->dispatch.close_fds = proc_close_fds;
 237         cl->dispatch.proc.r.header_cb = proc_handle_header;
 238         cl->dispatch.proc.r.header_end = proc_handle_header_end;
 239         cl->dispatch.proc.r.close = proc_handle_close;
 240
 241         return true;
 242 }