• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Gopher protocol
3  *
4  * Copyright (c) 2009 Toshimitsu Kimura
5  * Copyright (c) 2021 parazyd <parazyd@dyne.org>
6  *
7  * based on libavformat/http.c, Copyright (c) 2000, 2001 Fabrice Bellard
8  *
9  * This file is part of FFmpeg.
10  *
11  * FFmpeg is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU Lesser General Public
13  * License as published by the Free Software Foundation; either
14  * version 2.1 of the License, or (at your option) any later version.
15  *
16  * FFmpeg is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  * Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public
22  * License along with FFmpeg; if not, write to the Free Software
23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24  */
25 
26 #include "config.h"
27 
28 #include "libavutil/avstring.h"
29 #include "avformat.h"
30 #include "internal.h"
31 #include "network.h"
32 #include "url.h"
33 
34 typedef struct GopherContext {
35     URLContext *hd;
36 } GopherContext;
37 
gopher_write(URLContext * h,const uint8_t * buf,int size)38 static int gopher_write(URLContext *h, const uint8_t *buf, int size)
39 {
40     GopherContext *s = h->priv_data;
41     return ffurl_write(s->hd, buf, size);
42 }
43 
gopher_connect(URLContext * h,const char * path)44 static int gopher_connect(URLContext *h, const char *path)
45 {
46     char buffer[1024];
47 
48     if (!*path) return AVERROR(EINVAL);
49     switch (*++path) {
50         case '5':
51         case '9':
52             path = strchr(path, '/');
53             if (!path) return AVERROR(EINVAL);
54             break;
55         default:
56             av_log(h, AV_LOG_WARNING,
57                    "Gopher protocol type '%c' not supported yet!\n",
58                    *path);
59             return AVERROR(EINVAL);
60     }
61 
62     /* send gopher sector */
63     snprintf(buffer, sizeof(buffer), "%s\r\n", path);
64 
65     if (gopher_write(h, buffer, strlen(buffer)) < 0)
66         return AVERROR(EIO);
67 
68     return 0;
69 }
70 
gopher_close(URLContext * h)71 static int gopher_close(URLContext *h)
72 {
73     GopherContext *s = h->priv_data;
74     ffurl_closep(&s->hd);
75     return 0;
76 }
77 
gopher_open(URLContext * h,const char * uri,int flags)78 static int gopher_open(URLContext *h, const char *uri, int flags)
79 {
80     GopherContext *s = h->priv_data;
81     char proto[10], hostname[1024], auth[1024], path[1024], buf[1024];
82     int port, err;
83     const char *lower_proto = "tcp";
84 
85     h->is_streamed = 1;
86 
87     /* needed in any case to build the host string */
88     av_url_split(proto, sizeof(proto), auth, sizeof(auth),
89                  hostname, sizeof(hostname), &port, path, sizeof(path), uri);
90 
91     if (port < 0)
92         port = 70;
93 
94     if (!strcmp(proto, "gophers"))
95         lower_proto = "tls";
96 
97     ff_url_join(buf, sizeof(buf), lower_proto, NULL, hostname, port, NULL);
98 
99     s->hd = NULL;
100     err = ffurl_open_whitelist(&s->hd, buf, AVIO_FLAG_READ_WRITE,
101                                &h->interrupt_callback, NULL, h->protocol_whitelist, h->protocol_blacklist, h);
102     if (err < 0)
103         goto fail;
104 
105     if ((err = gopher_connect(h, path)) < 0)
106         goto fail;
107     return 0;
108  fail:
109     gopher_close(h);
110     return err;
111 }
112 
gopher_read(URLContext * h,uint8_t * buf,int size)113 static int gopher_read(URLContext *h, uint8_t *buf, int size)
114 {
115     GopherContext *s = h->priv_data;
116     int len = ffurl_read(s->hd, buf, size);
117     return len;
118 }
119 
120 #if CONFIG_GOPHER_PROTOCOL
121 const URLProtocol ff_gopher_protocol = {
122     .name              = "gopher",
123     .url_open          = gopher_open,
124     .url_read          = gopher_read,
125     .url_write         = gopher_write,
126     .url_close         = gopher_close,
127     .priv_data_size    = sizeof(GopherContext),
128     .flags             = URL_PROTOCOL_FLAG_NETWORK,
129     .default_whitelist = "gopher,tcp"
130 };
131 #endif /* CONFIG_GOPHER_PROTOCOL */
132 
133 #if CONFIG_GOPHERS_PROTOCOL
134 const URLProtocol ff_gophers_protocol = {
135     .name              = "gophers",
136     .url_open          = gopher_open,
137     .url_read          = gopher_read,
138     .url_write         = gopher_write,
139     .url_close         = gopher_close,
140     .priv_data_size    = sizeof(GopherContext),
141     .flags             = URL_PROTOCOL_FLAG_NETWORK,
142     .default_whitelist = "gopher,gophers,tcp,tls"
143 };
144 #endif /* CONFIG_GOPHERS_PROTOCOL */
145