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         s->eof = true;
  59         ustream_get_read_buf(s, &len);
  60         if (len)
  61                 ustream_consume(s, len);
  62         ustream_state_change(s);
  63 }
  64
  65 static void relay_process_headers(struct relay *r)
  66 {
  67         struct ustream *s = &r->sfd.stream;
  68         char *buf, *newline;
  69         int len;
  70
  71         if (!r->header_cb)
  72                 return;
  73
  74         while (r->header_cb) {
  75                 int line_len;
  76                 char *val;
  77
  78                 buf = ustream_get_read_buf(s, &len);
  79                 if (!buf || !len)
  80                         break;
  81
  82                 newline = strchr(buf, '\n');
  83                 if (!newline)
  84                         break;
  85
  86                 line_len = newline + 1 - buf;
  87                 if (newline > buf && newline[-1] == '\r')
  88                         newline--;
  89
  90                 *newline = 0;
  91                 if (newline == buf) {
  92                         r->header_cb = NULL;
  93                         if (r->header_end)
  94                                 r->header_end(r);
  95                         ustream_consume(s, line_len);
  96                         break;
  97                 }
  98
  99                 val = uh_split_header(buf);
 100                 if (!val) {
 101                         relay_error(r);
 102                         return;
 103                 }
 104
 105                 r->header_cb(r, buf, val);
 106                 ustream_consume(s, line_len);
 107         }
 108 }
 109
 110 static void relay_read_cb(struct ustream *s, int bytes)
 111 {
 112         struct relay *r = container_of(s, struct relay, sfd.stream);
 113         struct client *cl = r->cl;
 114         struct ustream *us = cl->us;
 115         char *buf;
 116         int len;
 117
 118         relay_process_headers(r);
 119
 120         if (r->header_cb) {
 121                 /*
 122                  * if eof, ensure that remaining data is discarded, so the
 123                  * state change cb will tear down the stream
 124                  */
 125                 if (s->eof)
 126                         relay_error(r);
 127                 return;
 128         }
 129
 130         if (!s->eof && ustream_pending_data(us, true)) {
 131                 ustream_set_read_blocked(s, true);
 132                 return;
 133         }
 134
 135         buf = ustream_get_read_buf(s, &len);
 136         if (!buf || !len)
 137                 return;
 138
 139         uh_chunk_write(cl, buf, len);
 140         ustream_consume(s, len);
 141 }
 142
 143 static void relay_close_if_done(struct relay *r)
 144 {
 145         struct ustream *s = &r->sfd.stream;
 146
 147         if (!s->eof || ustream_pending_data(s, false))
 148                 return;
 149
 150         uh_relay_close(r, r->ret);
 151 }
 152
 153 static void relay_state_cb(struct ustream *s)
 154 {
 155         struct relay *r = container_of(s, struct relay, sfd.stream);
 156
 157         if (r->process_done)
 158                 relay_close_if_done(r);
 159 }
 160
 161 static void relay_proc_cb(struct uloop_process *proc, int ret)
 162 {
 163         struct relay *r = container_of(proc, struct relay, proc);
 164
 165         ustream_poll(&r->sfd.stream);
 166         r->process_done = true;
 167         r->ret = ret;
 168         relay_close_if_done(r);
 169 }
 170
 171 void uh_relay_kill(struct client *cl, struct relay *r)
 172 {
 173         struct ustream *us = &r->sfd.stream;
 174
 175         kill(r->proc.pid, SIGKILL);
 176         us->eof = true;
 177         ustream_state_change(us);
 178 }
 179
 180 void uh_relay_open(struct client *cl, struct relay *r, int fd, int pid)
 181 {
 182         struct ustream *us = &r->sfd.stream;
 183
 184         r->cl = cl;
 185         us->notify_read = relay_read_cb;
 186         us->notify_state = relay_state_cb;
 187         us->string_data = true;
 188         ustream_fd_init(&r->sfd, fd);
 189
 190         r->proc.pid = pid;
 191         r->proc.cb = relay_proc_cb;
 192         uloop_process_add(&r->proc);
 193 }