relay.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd
   3  *
   4  *   Copyright (C) 2010-2013 Jo-Philipp Wich <xm@subsignal.org>
   5  *   Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #include <signal.h>
  21 #include "uhttpd.h"
  22
  23 void uh_relay_free(struct relay *r)
  24 {
  25         if (!r->cl)
  26                 return;
  27
  28         if (r->proc.pending)
  29                 kill(r->proc.pid, SIGKILL);
  30
  31         uloop_process_delete(&r->proc);
  32         ustream_free(&r->sfd.stream);
  33         close(r->sfd.fd.fd);
  34
  35         r->cl = NULL;
  36 }
  37
  38 void uh_relay_close(struct relay *r, int ret)
  39 {
  40         struct ustream *us = &r->sfd.stream;
  41
  42         if (!us->notify_read)
  43                 return;
  44
  45         us->notify_read = NULL;
  46         us->notify_write = NULL;
  47         us->notify_state = NULL;
  48
  49         if (r->close)
  50                 r->close(r, ret);
  51 }
  52
  53 static void relay_error(struct relay *r)
  54 {
  55         struct ustream *s = &r->sfd.stream;
  56         int len;
  57
  58         r->error = true;
  59         s->eof = true;
  60         ustream_get_read_buf(s, &len);
  61         if (len)
  62                 ustream_consume(s, len);
  63         ustream_state_change(s);
  64 }
  65
  66 static void relay_process_headers(struct relay *r)
  67 {
  68         struct ustream *s = &r->sfd.stream;
  69         char *buf, *newline;
  70         int len;
  71
  72         if (!r->header_cb)
  73                 return;
  74
  75         while (r->header_cb) {
  76                 int line_len;
  77                 char *val;
  78
  79                 buf = ustream_get_read_buf(s, &len);
  80                 if (!buf || !len)
  81                         break;
  82
  83                 newline = strchr(buf, '\n');
  84                 if (!newline)
  85                         break;
  86
  87                 line_len = newline + 1 - buf;
  88                 if (newline > buf && newline[-1] == '\r')
  89                         newline--;
  90
  91                 *newline = 0;
  92                 if (newline == buf) {
  93                         r->header_cb = NULL;
  94                         if (r->header_end)
  95                                 r->header_end(r);
  96                         ustream_consume(s, line_len);
  97                         break;
  98                 }
  99
 100                 val = uh_split_header(buf);
 101                 if (!val) {
 102                         relay_error(r);
 103                         return;
 104                 }
 105
 106                 r->header_cb(r, buf, val);
 107                 ustream_consume(s, line_len);
 108         }
 109 }
 110
 111 static void relay_read_cb(struct ustream *s, int bytes)
 112 {
 113         struct relay *r = container_of(s, struct relay, sfd.stream);
 114         struct client *cl = r->cl;
 115         struct ustream *us = cl->us;
 116         char *buf;
 117         int len;
 118
 119         if (r->process_done)
 120                 uloop_timeout_set(&r->timeout, 1);
 121
 122         if (!r->error)
 123                 relay_process_headers(r);
 124
 125         if (r->header_cb) {
 126                 /*
 127                  * if eof, ensure that remaining data is discarded, so the
 128                  * state change cb will tear down the stream
 129                  */
 130                 if (s->eof)
 131                         relay_error(r);
 132                 return;
 133         }
 134
 135         if (!s->eof && ustream_pending_data(us, true)) {
 136                 ustream_set_read_blocked(s, true);
 137                 return;
 138         }
 139
 140         buf = ustream_get_read_buf(s, &len);
 141         if (!buf || !len)
 142                 return;
 143
 144         uh_chunk_write(cl, buf, len);
 145         ustream_consume(s, len);
 146 }
 147
 148 static void relay_close_if_done(struct uloop_timeout *timeout)
 149 {
 150         struct relay *r = container_of(timeout, struct relay, timeout);
 151         struct ustream *s = &r->sfd.stream;
 152
 153         while (ustream_poll(&r->sfd.stream));
 154
 155         if (!(r->process_done || s->eof) || ustream_pending_data(s, false))
 156                 return;
 157
 158         uh_relay_close(r, r->ret);
 159 }
 160
 161 static void relay_state_cb(struct ustream *s)
 162 {
 163         struct relay *r = container_of(s, struct relay, sfd.stream);
 164
 165         if (r->process_done)
 166                 uloop_timeout_set(&r->timeout, 1);
 167 }
 168
 169 static void relay_proc_cb(struct uloop_process *proc, int ret)
 170 {
 171         struct relay *r = container_of(proc, struct relay, proc);
 172
 173         r->process_done = true;
 174         r->ret = ret;
 175         uloop_timeout_set(&r->timeout, 1);
 176 }
 177
 178 void uh_relay_kill(struct client *cl, struct relay *r)
 179 {
 180         struct ustream *us = &r->sfd.stream;
 181
 182         kill(r->proc.pid, SIGKILL);
 183         us->eof = true;
 184         ustream_state_change(us);
 185 }
 186
 187 void uh_relay_open(struct client *cl, struct relay *r, int fd, int pid)
 188 {
 189         struct ustream *us = &r->sfd.stream;
 190
 191         r->cl = cl;
 192         us->notify_read = relay_read_cb;
 193         us->notify_state = relay_state_cb;
 194         us->string_data = true;
 195         ustream_fd_init(&r->sfd, fd);
 196
 197         r->proc.pid = pid;
 198         r->proc.cb = relay_proc_cb;
 199         uloop_process_add(&r->proc);
 200
 201         r->timeout.cb = relay_close_if_done;
 202 }