blob: 0809b63cb055a204a0eccbb05d28af88d73ef022 [file] [log] [blame]
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07001/*
2 * net/dccp/options.c
3 *
4 * An implementation of the DCCP protocol
Ian McDonald1bc09862005-08-20 00:23:43 -03005 * Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
6 * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Ian McDonalde6bccd32006-08-26 19:01:30 -07007 * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz>
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -07008 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070014#include <linux/dccp.h>
15#include <linux/module.h>
16#include <linux/types.h>
Gerrit Renker76fd1e82007-10-24 10:46:58 -020017#include <asm/unaligned.h>
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070018#include <linux/kernel.h>
19#include <linux/skbuff.h>
20
Arnaldo Carvalho de Meloae31c332005-09-18 00:17:51 -070021#include "ackvec.h"
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070022#include "ccid.h"
23#include "dccp.h"
Andrea Bittauafe00252006-03-20 17:43:56 -080024#include "feat.h"
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070025
Gerrit Renker410e27a2008-09-09 13:27:22 +020026int sysctl_dccp_feat_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW;
27int sysctl_dccp_feat_rx_ccid = DCCPF_INITIAL_CCID;
28int sysctl_dccp_feat_tx_ccid = DCCPF_INITIAL_CCID;
29int sysctl_dccp_feat_ack_ratio = DCCPF_INITIAL_ACK_RATIO;
30int sysctl_dccp_feat_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR;
31int sysctl_dccp_feat_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070032
Gerrit Renker410e27a2008-09-09 13:27:22 +020033static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)
34{
35 u32 value = 0;
36
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070037 if (len > 3)
Gerrit Renker410e27a2008-09-09 13:27:22 +020038 value += *bf++ << 24;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070039 if (len > 2)
Gerrit Renker410e27a2008-09-09 13:27:22 +020040 value += *bf++ << 16;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070041 if (len > 1)
Gerrit Renker410e27a2008-09-09 13:27:22 +020042 value += *bf++ << 8;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070043 if (len > 0)
44 value += *bf;
45
46 return value;
47}
48
Gerrit Renker8b819412007-12-13 12:29:24 -020049/**
50 * dccp_parse_options - Parse DCCP options present in @skb
51 * @sk: client|server|listening dccp socket (when @dreq != NULL)
52 * @dreq: request socket to use during connection setup, or NULL
53 */
54int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq,
55 struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070056{
57 struct dccp_sock *dp = dccp_sk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070058 const struct dccp_hdr *dh = dccp_hdr(skb);
59 const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type;
Gerrit Renker410e27a2008-09-09 13:27:22 +020060 u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070061 unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb);
62 unsigned char *opt_ptr = options;
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -030063 const unsigned char *opt_end = (unsigned char *)dh +
64 (dh->dccph_doff * 4);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070065 struct dccp_options_received *opt_recv = &dp->dccps_options_received;
66 unsigned char opt, len;
67 unsigned char *value;
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -030068 u32 elapsed_time;
Gerrit Renker76fd1e82007-10-24 10:46:58 -020069 __be32 opt_val;
Andrea Bittauafe00252006-03-20 17:43:56 -080070 int rc;
71 int mandatory = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070072
73 memset(opt_recv, 0, sizeof(*opt_recv));
74
David S. Millerfb950492006-03-20 22:36:01 -080075 opt = len = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070076 while (opt_ptr != opt_end) {
77 opt = *opt_ptr++;
78 len = 0;
79 value = NULL;
80
81 /* Check if this isn't a single byte option */
82 if (opt > DCCPO_MAX_RESERVED) {
83 if (opt_ptr == opt_end)
Gerrit Renkerfaf61c332008-08-23 13:28:27 +020084 goto out_nonsensical_length;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070085
86 len = *opt_ptr++;
Gerrit Renkerfaf61c332008-08-23 13:28:27 +020087 if (len < 2)
88 goto out_nonsensical_length;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070089 /*
90 * Remove the type and len fields, leaving
91 * just the value size
92 */
93 len -= 2;
94 value = opt_ptr;
95 opt_ptr += len;
96
97 if (opt_ptr > opt_end)
Gerrit Renkerfaf61c332008-08-23 13:28:27 +020098 goto out_nonsensical_length;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -070099 }
100
Gerrit Renker8b819412007-12-13 12:29:24 -0200101 /*
Gerrit Renker410e27a2008-09-09 13:27:22 +0200102 * CCID-Specific Options (from RFC 4340, sec. 10.3):
103 *
104 * Option numbers 128 through 191 are for options sent from the
105 * HC-Sender to the HC-Receiver; option numbers 192 through 255
106 * are for options sent from the HC-Receiver to the HC-Sender.
107 *
Gerrit Renker8b819412007-12-13 12:29:24 -0200108 * CCID-specific options are ignored during connection setup, as
109 * negotiation may still be in progress (see RFC 4340, 10.3).
Gerrit Renker65907a42008-06-11 11:19:09 +0100110 * The same applies to Ack Vectors, as these depend on the CCID.
Gerrit Renker410e27a2008-09-09 13:27:22 +0200111 *
Gerrit Renker8b819412007-12-13 12:29:24 -0200112 */
Gerrit Renker410e27a2008-09-09 13:27:22 +0200113 if (dreq != NULL && (opt >= 128 ||
Gerrit Renker65907a42008-06-11 11:19:09 +0100114 opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1))
Gerrit Renker8b819412007-12-13 12:29:24 -0200115 goto ignore_option;
116
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700117 switch (opt) {
118 case DCCPO_PADDING:
119 break;
Andrea Bittauafe00252006-03-20 17:43:56 -0800120 case DCCPO_MANDATORY:
121 if (mandatory)
122 goto out_invalid_option;
Arnaldo Carvalho de Melo6df94242006-03-20 22:06:02 -0800123 if (pkt_type != DCCP_PKT_DATA)
124 mandatory = 1;
Andrea Bittauafe00252006-03-20 17:43:56 -0800125 break;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700126 case DCCPO_NDP_COUNT:
Gerrit Renker5b5d0e72008-07-13 11:51:40 +0100127 if (len > 6)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700128 goto out_invalid_option;
129
130 opt_recv->dccpor_ndp = dccp_decode_value_var(value, len);
Gerrit Renker5b5d0e72008-07-13 11:51:40 +0100131 dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk),
132 (unsigned long long)opt_recv->dccpor_ndp);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700133 break;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200134 case DCCPO_CHANGE_L:
135 /* fall through */
136 case DCCPO_CHANGE_R:
137 if (pkt_type == DCCP_PKT_DATA)
Gerrit Renkercf863142007-12-13 12:48:19 -0200138 break;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200139 if (len < 2)
140 goto out_invalid_option;
141 rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
142 len - 1);
143 /*
144 * When there is a change error, change_recv is
145 * responsible for dealing with it. i.e. reply with an
146 * empty confirm.
147 * If the change was mandatory, then we need to die.
148 */
149 if (rc && mandatory)
150 goto out_invalid_option;
151 break;
152 case DCCPO_CONFIRM_L:
153 /* fall through */
154 case DCCPO_CONFIRM_R:
155 if (pkt_type == DCCP_PKT_DATA)
156 break;
157 if (len < 2) /* FIXME this disallows empty confirm */
158 goto out_invalid_option;
159 if (dccp_feat_confirm_recv(sk, opt, *value,
160 value + 1, len - 1))
161 goto out_invalid_option;
162 break;
163 case DCCPO_ACK_VECTOR_0:
164 case DCCPO_ACK_VECTOR_1:
165 if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */
166 break;
167
168 if (dccp_msk(sk)->dccpms_send_ack_vector &&
169 dccp_ackvec_parse(sk, skb, &ackno, opt, value, len))
170 goto out_invalid_option;
Andrea Bittauafe00252006-03-20 17:43:56 -0800171 break;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700172 case DCCPO_TIMESTAMP:
173 if (len != 4)
174 goto out_invalid_option;
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200175 /*
176 * RFC 4340 13.1: "The precise time corresponding to
177 * Timestamp Value zero is not specified". We use
178 * zero to indicate absence of a meaningful timestamp.
179 */
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200180 opt_val = get_unaligned((__be32 *)value);
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200181 if (unlikely(opt_val == 0)) {
182 DCCP_WARN("Timestamp with zero value\n");
183 break;
184 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700185
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200186 if (dreq != NULL) {
187 dreq->dreq_timestamp_echo = ntohl(opt_val);
188 dreq->dreq_timestamp_time = dccp_timestamp();
189 } else {
190 opt_recv->dccpor_timestamp =
191 dp->dccps_timestamp_echo = ntohl(opt_val);
192 dp->dccps_timestamp_time = dccp_timestamp();
193 }
Gerrit Renker09dbc382006-11-14 12:57:34 -0200194 dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n",
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200195 dccp_role(sk), ntohl(opt_val),
David S. Millerf6ccf552005-08-09 20:27:14 -0700196 (unsigned long long)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700197 DCCP_SKB_CB(skb)->dccpd_ack_seq);
198 break;
199 case DCCPO_TIMESTAMP_ECHO:
Ian McDonald1bc09862005-08-20 00:23:43 -0300200 if (len != 4 && len != 6 && len != 8)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700201 goto out_invalid_option;
202
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200203 opt_val = get_unaligned((__be32 *)value);
204 opt_recv->dccpor_timestamp_echo = ntohl(opt_val);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700205
Gerrit Renker09dbc382006-11-14 12:57:34 -0200206 dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, "
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700207 "ackno=%llu", dccp_role(sk),
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300208 opt_recv->dccpor_timestamp_echo,
David S. Millerf6ccf552005-08-09 20:27:14 -0700209 len + 2,
210 (unsigned long long)
Ian McDonald1bc09862005-08-20 00:23:43 -0300211 DCCP_SKB_CB(skb)->dccpd_ack_seq);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700212
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200213 value += 4;
Ian McDonald1bc09862005-08-20 00:23:43 -0300214
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200215 if (len == 4) { /* no elapsed time included */
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700216 dccp_pr_debug_cat("\n");
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300217 break;
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700218 }
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300219
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200220 if (len == 6) { /* 2-byte elapsed time */
221 __be16 opt_val2 = get_unaligned((__be16 *)value);
222 elapsed_time = ntohs(opt_val2);
223 } else { /* 4-byte elapsed time */
224 opt_val = get_unaligned((__be32 *)value);
225 elapsed_time = ntohl(opt_val);
226 }
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300227
Gerrit Renkerdcad8562007-10-04 14:44:01 -0700228 dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time);
Gerrit Renkerf73f7092007-04-20 13:56:47 -0700229
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300230 /* Give precedence to the biggest ELAPSED_TIME */
231 if (elapsed_time > opt_recv->dccpor_elapsed_time)
232 opt_recv->dccpor_elapsed_time = elapsed_time;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700233 break;
234 case DCCPO_ELAPSED_TIME:
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200235 if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */
236 break;
Ian McDonald1bc09862005-08-20 00:23:43 -0300237
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200238 if (len == 2) {
239 __be16 opt_val2 = get_unaligned((__be16 *)value);
240 elapsed_time = ntohs(opt_val2);
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200241 } else if (len == 4) {
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200242 opt_val = get_unaligned((__be32 *)value);
243 elapsed_time = ntohl(opt_val);
Gerrit Renkerc86ab2b2007-11-21 10:13:53 -0200244 } else {
245 goto out_invalid_option;
Gerrit Renker76fd1e82007-10-24 10:46:58 -0200246 }
Arnaldo Carvalho de Melo1c14ac02005-09-09 02:32:01 -0300247
248 if (elapsed_time > opt_recv->dccpor_elapsed_time)
249 opt_recv->dccpor_elapsed_time = elapsed_time;
Ian McDonald1bc09862005-08-20 00:23:43 -0300250
Gerrit Renker09dbc382006-11-14 12:57:34 -0200251 dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n",
252 dccp_role(sk), elapsed_time);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700253 break;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200254 case 128 ... 191: {
255 const u16 idx = value - options;
256
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300257 if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk,
Gerrit Renker410e27a2008-09-09 13:27:22 +0200258 opt, len, idx,
259 value) != 0)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700260 goto out_invalid_option;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200261 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700262 break;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200263 case 192 ... 255: {
264 const u16 idx = value - options;
265
Arnaldo Carvalho de Melo7690af32005-08-13 20:34:54 -0300266 if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk,
Gerrit Renker410e27a2008-09-09 13:27:22 +0200267 opt, len, idx,
268 value) != 0)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700269 goto out_invalid_option;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200270 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700271 break;
272 default:
Gerrit Renker59348b12006-11-20 18:39:23 -0200273 DCCP_CRIT("DCCP(%p): option %d(len=%d) not "
274 "implemented, ignoring", sk, opt, len);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700275 break;
YOSHIFUJI Hideakic9eaf172007-02-09 23:24:38 +0900276 }
Gerrit Renker8b819412007-12-13 12:29:24 -0200277ignore_option:
Andrea Bittauafe00252006-03-20 17:43:56 -0800278 if (opt != DCCPO_MANDATORY)
279 mandatory = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700280 }
281
Arnaldo Carvalho de Melo6df94242006-03-20 22:06:02 -0800282 /* mandatory was the last byte in option list -> reset connection */
283 if (mandatory)
284 goto out_invalid_option;
285
Gerrit Renkerfaf61c332008-08-23 13:28:27 +0200286out_nonsensical_length:
287 /* RFC 4340, 5.8: ignore option and all remaining option space */
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700288 return 0;
289
290out_invalid_option:
291 DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT);
Gerrit Renker410e27a2008-09-09 13:27:22 +0200292 DCCP_SKB_CB(skb)->dccpd_reset_code = DCCP_RESET_CODE_OPTION_ERROR;
293 DCCP_WARN("DCCP(%p): invalid option %d, len=%d", sk, opt, len);
Gerrit Renkereac77262008-08-23 13:28:27 +0200294 DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt;
295 DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0;
296 DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700297 return -1;
298}
299
Arnaldo Carvalho de Melob61fafc2006-03-20 21:25:11 -0800300EXPORT_SYMBOL_GPL(dccp_parse_options);
301
Gerrit Renker410e27a2008-09-09 13:27:22 +0200302static void dccp_encode_value_var(const u32 value, unsigned char *to,
303 const unsigned int len)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700304{
305 if (len > 3)
306 *to++ = (value & 0xFF000000) >> 24;
307 if (len > 2)
308 *to++ = (value & 0xFF0000) >> 16;
309 if (len > 1)
310 *to++ = (value & 0xFF00) >> 8;
311 if (len > 0)
312 *to++ = (value & 0xFF);
313}
314
Gerrit Renker5b5d0e72008-07-13 11:51:40 +0100315static inline u8 dccp_ndp_len(const u64 ndp)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700316{
Gerrit Renker5b5d0e72008-07-13 11:51:40 +0100317 if (likely(ndp <= 0xFF))
318 return 1;
319 return likely(ndp <= USHORT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700320}
321
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800322int dccp_insert_option(struct sock *sk, struct sk_buff *skb,
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700323 const unsigned char option,
324 const void *value, const unsigned char len)
325{
326 unsigned char *to;
327
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800328 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN)
329 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700330
331 DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2;
332
333 to = skb_push(skb, len + 2);
334 *to++ = option;
335 *to++ = len + 2;
336
337 memcpy(to, value, len);
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800338 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700339}
340
341EXPORT_SYMBOL_GPL(dccp_insert_option);
342
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800343static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700344{
345 struct dccp_sock *dp = dccp_sk(sk);
Gerrit Renker5b5d0e72008-07-13 11:51:40 +0100346 u64 ndp = dp->dccps_ndp_count;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700347
348 if (dccp_non_data_packet(skb))
349 ++dp->dccps_ndp_count;
350 else
351 dp->dccps_ndp_count = 0;
352
353 if (ndp > 0) {
354 unsigned char *ptr;
355 const int ndp_len = dccp_ndp_len(ndp);
356 const int len = ndp_len + 2;
357
358 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800359 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700360
361 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
362
363 ptr = skb_push(skb, len);
364 *ptr++ = DCCPO_NDP_COUNT;
365 *ptr++ = len;
366 dccp_encode_value_var(ndp, ptr, ndp_len);
367 }
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800368
369 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700370}
371
372static inline int dccp_elapsed_time_len(const u32 elapsed_time)
373{
Ian McDonaldb1c9fe72005-08-18 20:45:29 -0300374 return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700375}
376
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800377int dccp_insert_option_elapsed_time(struct sock *sk, struct sk_buff *skb,
378 u32 elapsed_time)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700379{
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700380 const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
381 const int len = 2 + elapsed_time_len;
382 unsigned char *to;
383
Ian McDonald1bc09862005-08-20 00:23:43 -0300384 if (elapsed_time_len == 0)
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800385 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700386
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800387 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
388 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700389
390 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
391
392 to = skb_push(skb, len);
393 *to++ = DCCPO_ELAPSED_TIME;
394 *to++ = len;
395
Ian McDonald1bc09862005-08-20 00:23:43 -0300396 if (elapsed_time_len == 2) {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800397 const __be16 var16 = htons((u16)elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300398 memcpy(to, &var16, 2);
399 } else {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800400 const __be32 var32 = htonl(elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300401 memcpy(to, &var32, 4);
402 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700403
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800404 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700405}
406
Arnaldo Carvalho de Melod4b81ff2005-08-23 21:51:36 -0700407EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700408
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800409int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700410{
Gerrit Renker4c70f382007-09-25 22:40:13 -0700411 __be32 now = htonl(dccp_timestamp());
Ian McDonald1bc09862005-08-20 00:23:43 -0300412 /* yes this will overflow but that is the point as we want a
413 * 10 usec 32 bit timer which mean it wraps every 11.9 hours */
414
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800415 return dccp_insert_option(sk, skb, DCCPO_TIMESTAMP, &now, sizeof(now));
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700416}
417
Arnaldo Carvalho de Melod4b81ff2005-08-23 21:51:36 -0700418EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp);
419
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200420static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp,
421 struct dccp_request_sock *dreq,
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800422 struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700423{
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800424 __be32 tstamp_echo;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700425 unsigned char *to;
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200426 u32 elapsed_time, elapsed_time_len, len;
427
428 if (dreq != NULL) {
429 elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time;
430 tstamp_echo = htonl(dreq->dreq_timestamp_echo);
431 dreq->dreq_timestamp_echo = 0;
432 } else {
433 elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time;
434 tstamp_echo = htonl(dp->dccps_timestamp_echo);
435 dp->dccps_timestamp_echo = 0;
436 }
437
Arnaldo Carvalho de Melob0e56782005-09-09 02:38:35 -0300438 elapsed_time_len = dccp_elapsed_time_len(elapsed_time);
439 len = 6 + elapsed_time_len;
440
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800441 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
442 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700443
444 DCCP_SKB_CB(skb)->dccpd_opt_len += len;
445
446 to = skb_push(skb, len);
447 *to++ = DCCPO_TIMESTAMP_ECHO;
448 *to++ = len;
449
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700450 memcpy(to, &tstamp_echo, 4);
451 to += 4;
Andrea Bittauafe00252006-03-20 17:43:56 -0800452
Ian McDonald1bc09862005-08-20 00:23:43 -0300453 if (elapsed_time_len == 2) {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800454 const __be16 var16 = htons((u16)elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300455 memcpy(to, &var16, 2);
456 } else if (elapsed_time_len == 4) {
Andrea Bittau60fe62e2006-03-20 19:23:32 -0800457 const __be32 var32 = htonl(elapsed_time);
Ian McDonald1bc09862005-08-20 00:23:43 -0300458 memcpy(to, &var32, 4);
459 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700460
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800461 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700462}
463
Gerrit Renker410e27a2008-09-09 13:27:22 +0200464static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
465 u8 *val, u8 len)
Gerrit Renker48290072008-09-04 07:30:19 +0200466{
Gerrit Renker410e27a2008-09-09 13:27:22 +0200467 u8 *to;
Gerrit Renker48290072008-09-04 07:30:19 +0200468
Gerrit Renker410e27a2008-09-09 13:27:22 +0200469 if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) {
Gerrit Renkercf9ddf72008-09-04 07:30:19 +0200470 DCCP_WARN("packet too small for feature %d option!\n", feat);
471 return -1;
472 }
Gerrit Renkercf9ddf72008-09-04 07:30:19 +0200473
Gerrit Renker410e27a2008-09-09 13:27:22 +0200474 DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
475
476 to = skb_push(skb, len + 3);
Andrea Bittauafe00252006-03-20 17:43:56 -0800477 *to++ = type;
Gerrit Renker410e27a2008-09-09 13:27:22 +0200478 *to++ = len + 3;
Andrea Bittauafe00252006-03-20 17:43:56 -0800479 *to++ = feat;
480
481 if (len)
482 memcpy(to, val, len);
Gerrit Renker410e27a2008-09-09 13:27:22 +0200483
484 dccp_pr_debug("%s(%s (%d), ...), length %d\n",
485 dccp_feat_typename(type),
486 dccp_feat_name(feat), feat, len);
487 return 0;
488}
489
490static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb)
491{
492 struct dccp_sock *dp = dccp_sk(sk);
493 struct dccp_minisock *dmsk = dccp_msk(sk);
494 struct dccp_opt_pend *opt, *next;
495 int change = 0;
496
497 /* confirm any options [NN opts] */
498 list_for_each_entry_safe(opt, next, &dmsk->dccpms_conf, dccpop_node) {
499 dccp_insert_feat_opt(skb, opt->dccpop_type,
500 opt->dccpop_feat, opt->dccpop_val,
501 opt->dccpop_len);
502 /* fear empty confirms */
503 if (opt->dccpop_val)
504 kfree(opt->dccpop_val);
505 kfree(opt);
506 }
507 INIT_LIST_HEAD(&dmsk->dccpms_conf);
508
509 /* see which features we need to send */
510 list_for_each_entry(opt, &dmsk->dccpms_pending, dccpop_node) {
511 /* see if we need to send any confirm */
512 if (opt->dccpop_sc) {
513 dccp_insert_feat_opt(skb, opt->dccpop_type + 1,
514 opt->dccpop_feat,
515 opt->dccpop_sc->dccpoc_val,
516 opt->dccpop_sc->dccpoc_len);
517
518 BUG_ON(!opt->dccpop_sc->dccpoc_val);
519 kfree(opt->dccpop_sc->dccpoc_val);
520 kfree(opt->dccpop_sc);
521 opt->dccpop_sc = NULL;
522 }
523
524 /* any option not confirmed, re-send it */
525 if (!opt->dccpop_conf) {
526 dccp_insert_feat_opt(skb, opt->dccpop_type,
527 opt->dccpop_feat, opt->dccpop_val,
528 opt->dccpop_len);
529 change++;
530 }
531 }
532
533 /* Retransmit timer.
534 * If this is the master listening sock, we don't set a timer on it. It
535 * should be fine because if the dude doesn't receive our RESPONSE
536 * [which will contain the CHANGE] he will send another REQUEST which
537 * will "retrnasmit" the change.
538 */
539 if (change && dp->dccps_role != DCCP_ROLE_LISTEN) {
540 dccp_pr_debug("reset feat negotiation timer %p\n", sk);
541
542 /* XXX don't reset the timer on re-transmissions. I.e. reset it
543 * only when sending new stuff i guess. Currently the timer
544 * never backs off because on re-transmission it just resets it!
545 */
546 inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
547 inet_csk(sk)->icsk_rto, DCCP_RTO_MAX);
548 }
549
Andrea Bittauafe00252006-03-20 17:43:56 -0800550 return 0;
551}
552
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200553/* The length of all options needs to be a multiple of 4 (5.8) */
554static void dccp_insert_option_padding(struct sk_buff *skb)
555{
556 int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4;
557
558 if (padding != 0) {
559 padding = 4 - padding;
560 memset(skb_push(skb, padding), 0, padding);
561 DCCP_SKB_CB(skb)->dccpd_opt_len += padding;
562 }
563}
564
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800565int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700566{
567 struct dccp_sock *dp = dccp_sk(sk);
Gerrit Renker410e27a2008-09-09 13:27:22 +0200568 struct dccp_minisock *dmsk = dccp_msk(sk);
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700569
570 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
571
Gerrit Renker410e27a2008-09-09 13:27:22 +0200572 if (dmsk->dccpms_send_ndp_count &&
573 dccp_insert_option_ndp(sk, skb))
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800574 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700575
Gerrit Renker410e27a2008-09-09 13:27:22 +0200576 if (!dccp_packet_without_ack(skb)) {
577 if (dmsk->dccpms_send_ack_vector &&
578 dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
579 dccp_insert_option_ackvec(sk, skb))
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800580 return -1;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700581 }
582
Arnaldo Carvalho de Melo507d37c2005-09-09 02:30:07 -0300583 if (dp->dccps_hc_rx_insert_options) {
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800584 if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb))
585 return -1;
Arnaldo Carvalho de Melo507d37c2005-09-09 02:30:07 -0300586 dp->dccps_hc_rx_insert_options = 0;
587 }
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700588
Gerrit Renker410e27a2008-09-09 13:27:22 +0200589 /* Feature negotiation */
590 /* Data packets can't do feat negotiation */
591 if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA &&
592 DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATAACK &&
593 dccp_insert_options_feat(sk, skb))
594 return -1;
595
596 /*
597 * Obtain RTT sample from Request/Response exchange.
598 * This is currently used in CCID 3 initialisation.
599 */
600 if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST &&
601 dccp_insert_option_timestamp(sk, skb))
602 return -1;
603
Gerrit Renkerb4d4f7c2007-12-13 12:37:19 -0200604 if (dp->dccps_timestamp_echo != 0 &&
605 dccp_insert_option_timestamp_echo(dp, NULL, skb))
606 return -1;
607
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200608 dccp_insert_option_padding(skb);
609 return 0;
610}
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700611
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200612int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
613{
614 DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700615
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200616 if (dreq->dreq_timestamp_echo != 0 &&
617 dccp_insert_option_timestamp_echo(NULL, dreq, skb))
618 return -1;
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800619
Gerrit Renkeraf3b8672007-12-13 12:38:11 -0200620 dccp_insert_option_padding(skb);
Arnaldo Carvalho de Melo2d0817d2006-03-20 22:32:06 -0800621 return 0;
Arnaldo Carvalho de Melo7c657872005-08-09 20:14:34 -0700622}