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 #include "config_components.h"
28
29 #include "libavutil/avstring.h"
30 #include "avformat.h"
31 #include "internal.h"
32 #include "network.h"
33 #include "url.h"
34
35 typedef struct GopherContext {
36 URLContext *hd;
37 } GopherContext;
38
gopher_write(URLContext * h,const uint8_t * buf,int size)39 static int gopher_write(URLContext *h, const uint8_t *buf, int size)
40 {
41 GopherContext *s = h->priv_data;
42 return ffurl_write(s->hd, buf, size);
43 }
44
gopher_connect(URLContext * h,const char * path)45 static int gopher_connect(URLContext *h, const char *path)
46 {
47 char buffer[1024];
48
49 if (!*path) return AVERROR(EINVAL);
50 switch (*++path) {
51 case '5':
52 case '9':
53 path = strchr(path, '/');
54 if (!path) return AVERROR(EINVAL);
55 break;
56 default:
57 av_log(h, AV_LOG_WARNING,
58 "Gopher protocol type '%c' not supported yet!\n",
59 *path);
60 return AVERROR(EINVAL);
61 }
62
63 /* send gopher sector */
64 snprintf(buffer, sizeof(buffer), "%s\r\n", path);
65
66 if (gopher_write(h, buffer, strlen(buffer)) < 0)
67 return AVERROR(EIO);
68
69 return 0;
70 }
71
gopher_close(URLContext * h)72 static int gopher_close(URLContext *h)
73 {
74 GopherContext *s = h->priv_data;
75 ffurl_closep(&s->hd);
76 return 0;
77 }
78
gopher_open(URLContext * h,const char * uri,int flags)79 static int gopher_open(URLContext *h, const char *uri, int flags)
80 {
81 GopherContext *s = h->priv_data;
82 char proto[10], hostname[1024], auth[1024], path[1024], buf[1024];
83 int port, err;
84 const char *lower_proto = "tcp";
85
86 h->is_streamed = 1;
87
88 /* needed in any case to build the host string */
89 av_url_split(proto, sizeof(proto), auth, sizeof(auth),
90 hostname, sizeof(hostname), &port, path, sizeof(path), uri);
91
92 if (port < 0)
93 port = 70;
94
95 if (!strcmp(proto, "gophers"))
96 lower_proto = "tls";
97
98 ff_url_join(buf, sizeof(buf), lower_proto, NULL, hostname, port, NULL);
99
100 s->hd = NULL;
101 err = ffurl_open_whitelist(&s->hd, buf, AVIO_FLAG_READ_WRITE,
102 &h->interrupt_callback, NULL, h->protocol_whitelist, h->protocol_blacklist, h);
103 if (err < 0)
104 goto fail;
105
106 if ((err = gopher_connect(h, path)) < 0)
107 goto fail;
108 return 0;
109 fail:
110 gopher_close(h);
111 return err;
112 }
113
gopher_read(URLContext * h,uint8_t * buf,int size)114 static int gopher_read(URLContext *h, uint8_t *buf, int size)
115 {
116 GopherContext *s = h->priv_data;
117 int len = ffurl_read(s->hd, buf, size);
118 return len;
119 }
120
121 #if CONFIG_GOPHER_PROTOCOL
122 const URLProtocol ff_gopher_protocol = {
123 .name = "gopher",
124 .url_open = gopher_open,
125 .url_read = gopher_read,
126 .url_write = gopher_write,
127 .url_close = gopher_close,
128 .priv_data_size = sizeof(GopherContext),
129 .flags = URL_PROTOCOL_FLAG_NETWORK,
130 .default_whitelist = "gopher,tcp"
131 };
132 #endif /* CONFIG_GOPHER_PROTOCOL */
133
134 #if CONFIG_GOPHERS_PROTOCOL
135 const URLProtocol ff_gophers_protocol = {
136 .name = "gophers",
137 .url_open = gopher_open,
138 .url_read = gopher_read,
139 .url_write = gopher_write,
140 .url_close = gopher_close,
141 .priv_data_size = sizeof(GopherContext),
142 .flags = URL_PROTOCOL_FLAG_NETWORK,
143 .default_whitelist = "gopher,gophers,tcp,tls"
144 };
145 #endif /* CONFIG_GOPHERS_PROTOCOL */
146