Merge branch 't/test_man'
[paraslash.git] / dccp_send.c
1 /*
2 * Copyright (C) 2006-2014 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 <netinet/in.h>
15 #include <sys/socket.h>
16 #include <regex.h>
17 #include <sys/types.h>
18 #include <osl.h>
19 #include <arpa/inet.h>
20 #include <sys/un.h>
21 #include <netdb.h>
22
23 #include "para.h"
24 #include "error.h"
25 #include "string.h"
26 #include "afh.h"
27 #include "afs.h"
28 #include "server.h"
29 #include "net.h"
30 #include "list.h"
31 #include "send.h"
32 #include "sched.h"
33 #include "vss.h"
34 #include "fd.h"
35 #include "close_on_fork.h"
36 #include "chunk_queue.h"
37 #include "server.cmdline.h"
38 #include "acl.h"
39
40 static struct sender_status dccp_sender_status, *dss = &dccp_sender_status;
41
42 struct dccp_fec_client {
43 struct fec_client_parms fcp;
44 struct fec_client *fc;
45 };
46
47 static void dccp_pre_select(int *max_fileno, fd_set *rfds,
48 __a_unused fd_set *wfds)
49 {
50 if (dss->listen_fd >= 0)
51 para_fd_set(dss->listen_fd, rfds, max_fileno);
52 }
53
54 /**
55 * Query the TX CCID used on the sender-client half connection.
56 * \param sockfd Server socket descriptor to query (after accept(2)).
57 * \return CCID number > 0, -1 on error/incompatibility.
58 *
59 * NB: This feature is only available on Linux > 2.6.30; on older kernels
60 * ENOPROTOOPT ("Protocol not available") will be returned.
61 */
62 static int dccp_get_tx_ccid(int sockfd)
63 {
64 int tx_ccid;
65 socklen_t len = sizeof(tx_ccid);
66
67 if (getsockopt(sockfd, SOL_DCCP,
68 DCCP_SOCKOPT_TX_CCID, &tx_ccid, &len) < 0) {
69 PARA_WARNING_LOG("DCCP_SOCKOPT_TX_CCID: %s\n", strerror(errno));
70 return -1;
71 }
72 return tx_ccid;
73 }
74
75 static void dccp_shutdown_client(struct sender_client *sc)
76 {
77 struct dccp_fec_client *dfc = sc->private_data;
78
79 vss_del_fec_client(dfc->fc);
80 shutdown_client(sc, dss);
81 }
82
83 static void dccp_shutdown_clients(void)
84 {
85 struct sender_client *sc, *tmp;
86
87 list_for_each_entry_safe(sc, tmp, &dss->client_list, node)
88 dccp_shutdown_client(sc);
89 }
90
91 /** * Obtain current MPS according to RFC 4340, sec. 14. */
92 static int dccp_init_fec(struct sender_client *sc)
93 {
94 int mps, ret;
95 socklen_t ml = sizeof(mps);
96
97 /* If call fails, return some sensible minimum value */
98 ret = getsockopt(sc->fd, SOL_DCCP, DCCP_SOCKOPT_GET_CUR_MPS, &mps, &ml);
99 if (ret < 0) {
100 PARA_NOTICE_LOG("can not determine MPS: %s\n", strerror(errno));
101 mps = generic_max_transport_msg_size(sc->fd) - DCCP_MAX_HEADER;
102 }
103 PARA_INFO_LOG("current MPS = %d bytes\n", mps);
104 assert(mps > 0);
105 if (conf.dccp_max_slice_size_arg > 0)
106 mps = PARA_MIN(mps, conf.dccp_max_slice_size_arg);
107 return mps;
108 }
109
110 static void dccp_send_fec(struct sender_client *sc, char *buf, size_t len)
111 {
112 int ret = xwrite(sc->fd, buf, len);
113
114 if (ret < 0)
115 dccp_shutdown_client(sc);
116 }
117
118 static void dccp_post_select(fd_set *rfds, __a_unused fd_set *wfds)
119 {
120 struct sender_client *sc;
121 struct dccp_fec_client *dfc;
122 int tx_ccid;
123
124 sc = accept_sender_client(dss, rfds);
125 if (!sc)
126 return;
127
128 /* If CCID identifiable, present client as <host>#<port>~<ccid> */
129 tx_ccid = dccp_get_tx_ccid(sc->fd);
130 if (tx_ccid != -1) {
131 char *tmp = make_message("%s~%d", sc->name, tx_ccid);
132
133 free(sc->name);
134 sc->name = tmp;
135 }
136 /*
137 * Bypass unused CCID paths: the sender does not receive application data
138 * from the client; by shutting down this unused communication path we can
139 * reduce processing costs a bit. See analogous comment in dccp_recv.c.
140 */
141 if (shutdown(sc->fd, SHUT_RD) < 0) {
142 PARA_WARNING_LOG("%s\n", strerror(errno));
143 shutdown_client(sc, dss);
144 return;
145 }
146 dfc = para_calloc(sizeof(*dfc));
147 sc->private_data = dfc;
148 dfc->fcp.data_slices_per_group = conf.dccp_data_slices_per_group_arg;
149 dfc->fcp.slices_per_group = conf.dccp_slices_per_group_arg;
150 dfc->fcp.init_fec = dccp_init_fec;
151 dfc->fcp.send_fec = dccp_send_fec;
152 dfc->fcp.need_periodic_header = false;
153 dfc->fc = vss_add_fec_client(sc, &dfc->fcp);
154 }
155
156 static int dccp_com_on(__a_unused struct sender_command_data *scd)
157 {
158 return generic_com_on(dss, IPPROTO_DCCP);
159 }
160
161 static int dccp_com_off(__a_unused struct sender_command_data *scd)
162 {
163 dccp_shutdown_clients();
164 generic_com_off(dss);
165 return 1;
166 }
167
168
169 static int dccp_com_deny(struct sender_command_data *scd)
170 {
171 generic_com_deny(scd, dss);
172 return 1;
173 }
174
175 static int dccp_com_allow(struct sender_command_data *scd)
176 {
177 generic_com_allow(scd, dss);
178 return 1;
179 }
180
181 /**
182 * Return list of available CCIDs or warning, in static buffer.
183 */
184 static const char *dccp_list_available_ccids(void)
185 {
186 /* Worst case length: n * 3 digits + n-1 spaces + '\0' */
187 static char list[DCCP_MAX_HOST_CCIDS * 4];
188 uint8_t *ccids;
189 int i, len, nccids;
190
191 nccids = dccp_available_ccids(&ccids);
192 if (nccids < 0) {
193 snprintf(list, sizeof(list), "Unable to query available CCIDs");
194 } else {
195 for (i = len = 0; i < nccids; i++)
196 len += snprintf(list + len, sizeof(list) - len,
197 "%s%d", i ? " " : "", ccids[i]);
198 }
199 return list;
200 }
201
202 static char *dccp_info(void)
203 {
204 char *info = get_sender_info(dss, "dccp");
205 char *ret = make_message("%s" "\tsupported ccids: %s\n",
206 info, dccp_list_available_ccids());
207 free(info);
208 return ret;
209 }
210
211 /**
212 * The init function of the dccp sender.
213 *
214 * \param s pointer to the dccp sender struct.
215 *
216 * It initializes all function pointers of \a s and starts
217 * listening on the given port.
218 */
219 void dccp_send_init(struct sender *s)
220 {
221 int ret, k, n;
222
223 s->info = dccp_info;
224 s->send = NULL;
225 s->pre_select = dccp_pre_select;
226 s->post_select = dccp_post_select;
227 s->shutdown_clients = dccp_shutdown_clients;
228 s->resolve_target = NULL;
229 s->help = generic_sender_help;
230 s->client_cmds[SENDER_ON] = dccp_com_on;
231 s->client_cmds[SENDER_OFF] = dccp_com_off;
232 s->client_cmds[SENDER_DENY] = dccp_com_deny;
233 s->client_cmds[SENDER_ALLOW] = dccp_com_allow;
234 s->client_cmds[SENDER_ADD] = NULL;
235 s->client_cmds[SENDER_DELETE] = NULL;
236
237 k = conf.dccp_data_slices_per_group_arg;
238 n = conf.dccp_slices_per_group_arg;
239
240 if (k <= 0 || n <= 0 || k >= n) {
241 PARA_WARNING_LOG("invalid FEC parameters, using defaults\n");
242 conf.dccp_data_slices_per_group_arg = 3;
243 conf.dccp_slices_per_group_arg = 4;
244 }
245
246 init_sender_status(dss, conf.dccp_access_arg, conf.dccp_access_given,
247 conf.dccp_port_arg, conf.dccp_max_clients_arg,
248 conf.dccp_default_deny_given);
249 ret = generic_com_on(dss, IPPROTO_DCCP);
250 if (ret < 0)
251 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
252 }