Merge branch 'maint'
[paraslash.git] / dccp_send.c
1 /*
2 * Copyright (C) 2006-2010 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file dccp_send.c Paraslash's dccp sender. */
8
9 /*
10 * based on server.c of dccp-cs-0.01.tar.bz2,
11 * (C) 2005 Ian McDonald <imcdnzl@gmail.com>
12 */
13
14 #include <regex.h>
15 #include <sys/types.h>
16 #include <dirent.h>
17 #include <osl.h>
18
19 #include "para.h"
20 #include "error.h"
21 #include "string.h"
22 #include "afh.h"
23 #include "afs.h"
24 #include "server.h"
25 #include "net.h"
26 #include "list.h"
27 #include "vss.h"
28 #include "send.h"
29 #include "fd.h"
30 #include "close_on_fork.h"
31 #include "chunk_queue.h"
32 #include "server.cmdline.h"
33 #include "acl.h"
34
35 /** Do not write more than that many bytes at once. */
36 #define DCCP_MAX_BYTES_PER_WRITE 1024
37
38 static struct sender_status dccp_sender_status, *dss = &dccp_sender_status;
39
40 static void dccp_pre_select(int *max_fileno, fd_set *rfds,
41 __a_unused fd_set *wfds)
42 {
43 if (dss->listen_fd >= 0)
44 para_fd_set(dss->listen_fd, rfds, max_fileno);
45 }
46
47 /**
48 * Query the TX CCID used on the sender-client half connection.
49 * \param sockfd Server socket descriptor to query (after accept(2)).
50 * \return CCID number > 0, -1 on error/incompatibility.
51 *
52 * NB: This feature is only available on Linux > 2.6.30; on older kernels
53 * ENOPROTOOPT ("Protocol not available") will be returned.
54 */
55 static int dccp_get_tx_ccid(int sockfd)
56 {
57 int tx_ccid;
58 socklen_t len = sizeof(tx_ccid);
59
60 if (getsockopt(sockfd, SOL_DCCP,
61 DCCP_SOCKOPT_TX_CCID, &tx_ccid, &len) < 0) {
62 PARA_WARNING_LOG("DCCP_SOCKOPT_TX_CCID: %s\n", strerror(errno));
63 return -1;
64 }
65 return tx_ccid;
66 }
67
68 static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds)
69 {
70 struct sender_client *sc;
71 int tx_ccid;
72
73 if (dss->listen_fd < 0 || !FD_ISSET(dss->listen_fd, rfds))
74 return;
75 sc = accept_sender_client(dss);
76 if (!sc)
77 return;
78
79 /* If CCID identifiable, present client as <host>#<port>~<ccid> */
80 tx_ccid = dccp_get_tx_ccid(sc->fd);
81 if (tx_ccid != -1) {
82 char *tmp = make_message("%s~%d", sc->name, tx_ccid);
83
84 free(sc->name);
85 sc->name = tmp;
86 }
87 /*
88 * Bypass unused CCID paths: the sender does not receive application data
89 * from the client; by shutting down this unused communication path we can
90 * reduce processing costs a bit. See analogous comment in dccp_recv.c.
91 */
92 if (shutdown(sc->fd, SHUT_RD) >= 0)
93 return;
94 PARA_WARNING_LOG("%s\n", strerror(errno));
95 shutdown_client(sc, dss);
96 }
97
98 static void dccp_send(long unsigned current_chunk,
99 __a_unused long unsigned chunks_sent, const char *buf,
100 size_t len, const char *header_buf, size_t header_len)
101 {
102 struct sender_client *sc, *tmp;
103
104 list_for_each_entry_safe(sc, tmp, &dss->client_list, node)
105 send_chunk(sc, dss, DCCP_MAX_BYTES_PER_WRITE, current_chunk, buf,
106 len, header_buf, header_len);
107 }
108
109 static void dccp_shutdown_clients(void)
110 {
111 shutdown_clients(dss);
112 }
113
114 static int dccp_com_on(__a_unused struct sender_command_data *scd)
115 {
116 return generic_com_on(dss, IPPROTO_DCCP);
117 }
118
119 static int dccp_com_off(__a_unused struct sender_command_data *scd)
120 {
121 generic_com_off(dss);
122 return 1;
123 }
124
125
126 static int dccp_com_deny(struct sender_command_data *scd)
127 {
128 generic_com_deny(scd, dss);
129 return 1;
130 }
131
132 static int dccp_com_allow(struct sender_command_data *scd)
133 {
134 generic_com_allow(scd, dss);
135 return 1;
136 }
137
138 /**
139 * Return list of available CCIDs or warning, in static buffer.
140 */
141 static const char *dccp_list_available_ccids(void)
142 {
143 /* Worst case length: n * 3 digits + n-1 spaces + '\0' */
144 static char list[DCCP_MAX_HOST_CCIDS * 4];
145 uint8_t *ccids;
146 int i, len, nccids;
147
148 nccids = dccp_available_ccids(&ccids);
149 if (nccids < 0) {
150 snprintf(list, sizeof(list), "Unable to query available CCIDs");
151 } else {
152 for (i = len = 0; i < nccids; i++)
153 len += snprintf(list + len, sizeof(list) - len,
154 "%s%d", i ? " " : "", ccids[i]);
155 }
156 return list;
157 }
158
159 static char *dccp_info(void)
160 {
161 char *info = get_sender_info(dss, "dccp");
162 char *ret = make_message("%s" "\tsupported ccids: %s\n",
163 info, dccp_list_available_ccids());
164 free(info);
165 return ret;
166 }
167
168 /**
169 * The init function of the dccp sender.
170 *
171 * \param s pointer to the dccp sender struct.
172 *
173 * It initializes all function pointers of \a s and starts
174 * listening on the given port.
175 */
176 void dccp_send_init(struct sender *s)
177 {
178 int ret;
179
180 s->info = dccp_info;
181 s->send = dccp_send;
182 s->pre_select = dccp_pre_select;
183 s->post_select = dccp_post_select;
184 s->shutdown_clients = dccp_shutdown_clients;
185 s->help = generic_sender_help;
186 s->client_cmds[SENDER_ON] = dccp_com_on;
187 s->client_cmds[SENDER_OFF] = dccp_com_off;
188 s->client_cmds[SENDER_DENY] = dccp_com_deny;
189 s->client_cmds[SENDER_ALLOW] = dccp_com_allow;
190 s->client_cmds[SENDER_ADD] = NULL;
191 s->client_cmds[SENDER_DELETE] = NULL;
192
193 init_sender_status(dss, conf.dccp_access_arg, conf.dccp_access_given,
194 conf.dccp_port_arg, conf.dccp_max_clients_arg,
195 conf.dccp_default_deny_given);
196 ret = generic_com_on(dss, IPPROTO_DCCP);
197 if (ret < 0)
198 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
199 }