17c657876SArnaldo Carvalho de Melo /* 27c657876SArnaldo Carvalho de Melo * net/dccp/options.c 37c657876SArnaldo Carvalho de Melo * 47c657876SArnaldo Carvalho de Melo * An implementation of the DCCP protocol 51bc09869SIan McDonald * Copyright (c) 2005 Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org> 61bc09869SIan McDonald * Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@ghostprotocols.net> 7e6bccd35SIan McDonald * Copyright (c) 2005 Ian McDonald <ian.mcdonald@jandi.co.nz> 87c657876SArnaldo Carvalho de Melo * 97c657876SArnaldo Carvalho de Melo * This program is free software; you can redistribute it and/or 107c657876SArnaldo Carvalho de Melo * modify it under the terms of the GNU General Public License 117c657876SArnaldo Carvalho de Melo * as published by the Free Software Foundation; either version 127c657876SArnaldo Carvalho de Melo * 2 of the License, or (at your option) any later version. 137c657876SArnaldo Carvalho de Melo */ 147c657876SArnaldo Carvalho de Melo #include <linux/dccp.h> 157c657876SArnaldo Carvalho de Melo #include <linux/module.h> 167c657876SArnaldo Carvalho de Melo #include <linux/types.h> 1776fd1e87SGerrit Renker #include <asm/unaligned.h> 187c657876SArnaldo Carvalho de Melo #include <linux/kernel.h> 197c657876SArnaldo Carvalho de Melo #include <linux/skbuff.h> 207c657876SArnaldo Carvalho de Melo 21ae31c339SArnaldo Carvalho de Melo #include "ackvec.h" 227c657876SArnaldo Carvalho de Melo #include "ccid.h" 237c657876SArnaldo Carvalho de Melo #include "dccp.h" 24afe00251SAndrea Bittau #include "feat.h" 257c657876SArnaldo Carvalho de Melo 2602fa460eSGerrit Renker u64 dccp_decode_value_var(const u8 *bf, const u8 len) 27410e27a4SGerrit Renker { 2802fa460eSGerrit Renker u64 value = 0; 29410e27a4SGerrit Renker 3002fa460eSGerrit Renker if (len >= DCCP_OPTVAL_MAXLEN) 3102fa460eSGerrit Renker value += ((u64)*bf++) << 40; 3202fa460eSGerrit Renker if (len > 4) 3302fa460eSGerrit Renker value += ((u64)*bf++) << 32; 347c657876SArnaldo Carvalho de Melo if (len > 3) 3502fa460eSGerrit Renker value += ((u64)*bf++) << 24; 367c657876SArnaldo Carvalho de Melo if (len > 2) 3702fa460eSGerrit Renker value += ((u64)*bf++) << 16; 387c657876SArnaldo Carvalho de Melo if (len > 1) 3902fa460eSGerrit Renker value += ((u64)*bf++) << 8; 407c657876SArnaldo Carvalho de Melo if (len > 0) 417c657876SArnaldo Carvalho de Melo value += *bf; 427c657876SArnaldo Carvalho de Melo 437c657876SArnaldo Carvalho de Melo return value; 447c657876SArnaldo Carvalho de Melo } 457c657876SArnaldo Carvalho de Melo 468b819412SGerrit Renker /** 478b819412SGerrit Renker * dccp_parse_options - Parse DCCP options present in @skb 488b819412SGerrit Renker * @sk: client|server|listening dccp socket (when @dreq != NULL) 498b819412SGerrit Renker * @dreq: request socket to use during connection setup, or NULL 508b819412SGerrit Renker */ 518b819412SGerrit Renker int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, 528b819412SGerrit Renker struct sk_buff *skb) 537c657876SArnaldo Carvalho de Melo { 547c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 557c657876SArnaldo Carvalho de Melo const struct dccp_hdr *dh = dccp_hdr(skb); 567c657876SArnaldo Carvalho de Melo const u8 pkt_type = DCCP_SKB_CB(skb)->dccpd_type; 57410e27a4SGerrit Renker u64 ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; 587c657876SArnaldo Carvalho de Melo unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb); 597c657876SArnaldo Carvalho de Melo unsigned char *opt_ptr = options; 607690af3fSArnaldo Carvalho de Melo const unsigned char *opt_end = (unsigned char *)dh + 617690af3fSArnaldo Carvalho de Melo (dh->dccph_doff * 4); 627c657876SArnaldo Carvalho de Melo struct dccp_options_received *opt_recv = &dp->dccps_options_received; 637c657876SArnaldo Carvalho de Melo unsigned char opt, len; 643ed7cc0fSIngo Molnar unsigned char *uninitialized_var(value); 651c14ac0aSArnaldo Carvalho de Melo u32 elapsed_time; 6676fd1e87SGerrit Renker __be32 opt_val; 67afe00251SAndrea Bittau int rc; 68afe00251SAndrea Bittau int mandatory = 0; 697c657876SArnaldo Carvalho de Melo 707c657876SArnaldo Carvalho de Melo memset(opt_recv, 0, sizeof(*opt_recv)); 717c657876SArnaldo Carvalho de Melo 72fb950496SDavid S. Miller opt = len = 0; 737c657876SArnaldo Carvalho de Melo while (opt_ptr != opt_end) { 747c657876SArnaldo Carvalho de Melo opt = *opt_ptr++; 757c657876SArnaldo Carvalho de Melo len = 0; 767c657876SArnaldo Carvalho de Melo value = NULL; 777c657876SArnaldo Carvalho de Melo 787c657876SArnaldo Carvalho de Melo /* Check if this isn't a single byte option */ 797c657876SArnaldo Carvalho de Melo if (opt > DCCPO_MAX_RESERVED) { 807c657876SArnaldo Carvalho de Melo if (opt_ptr == opt_end) 81faf61c33SGerrit Renker goto out_nonsensical_length; 827c657876SArnaldo Carvalho de Melo 837c657876SArnaldo Carvalho de Melo len = *opt_ptr++; 84faf61c33SGerrit Renker if (len < 2) 85faf61c33SGerrit Renker goto out_nonsensical_length; 867c657876SArnaldo Carvalho de Melo /* 877c657876SArnaldo Carvalho de Melo * Remove the type and len fields, leaving 887c657876SArnaldo Carvalho de Melo * just the value size 897c657876SArnaldo Carvalho de Melo */ 907c657876SArnaldo Carvalho de Melo len -= 2; 917c657876SArnaldo Carvalho de Melo value = opt_ptr; 927c657876SArnaldo Carvalho de Melo opt_ptr += len; 937c657876SArnaldo Carvalho de Melo 947c657876SArnaldo Carvalho de Melo if (opt_ptr > opt_end) 95faf61c33SGerrit Renker goto out_nonsensical_length; 967c657876SArnaldo Carvalho de Melo } 977c657876SArnaldo Carvalho de Melo 988b819412SGerrit Renker /* 99410e27a4SGerrit Renker * CCID-Specific Options (from RFC 4340, sec. 10.3): 100410e27a4SGerrit Renker * 101410e27a4SGerrit Renker * Option numbers 128 through 191 are for options sent from the 102410e27a4SGerrit Renker * HC-Sender to the HC-Receiver; option numbers 192 through 255 103410e27a4SGerrit Renker * are for options sent from the HC-Receiver to the HC-Sender. 104410e27a4SGerrit Renker * 1058b819412SGerrit Renker * CCID-specific options are ignored during connection setup, as 1068b819412SGerrit Renker * negotiation may still be in progress (see RFC 4340, 10.3). 10765907a43SGerrit Renker * The same applies to Ack Vectors, as these depend on the CCID. 108410e27a4SGerrit Renker * 1098b819412SGerrit Renker */ 110410e27a4SGerrit Renker if (dreq != NULL && (opt >= 128 || 11165907a43SGerrit Renker opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1)) 1128b819412SGerrit Renker goto ignore_option; 1138b819412SGerrit Renker 1147c657876SArnaldo Carvalho de Melo switch (opt) { 1157c657876SArnaldo Carvalho de Melo case DCCPO_PADDING: 1167c657876SArnaldo Carvalho de Melo break; 117afe00251SAndrea Bittau case DCCPO_MANDATORY: 118afe00251SAndrea Bittau if (mandatory) 119afe00251SAndrea Bittau goto out_invalid_option; 1206df9424aSArnaldo Carvalho de Melo if (pkt_type != DCCP_PKT_DATA) 121afe00251SAndrea Bittau mandatory = 1; 122afe00251SAndrea Bittau break; 1237c657876SArnaldo Carvalho de Melo case DCCPO_NDP_COUNT: 1245b5d0e70SGerrit Renker if (len > 6) 1257c657876SArnaldo Carvalho de Melo goto out_invalid_option; 1267c657876SArnaldo Carvalho de Melo 1277c657876SArnaldo Carvalho de Melo opt_recv->dccpor_ndp = dccp_decode_value_var(value, len); 1285b5d0e70SGerrit Renker dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk), 1295b5d0e70SGerrit Renker (unsigned long long)opt_recv->dccpor_ndp); 1307c657876SArnaldo Carvalho de Melo break; 131b1ad0042SGerrit Renker case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R: 132b1ad0042SGerrit Renker if (pkt_type == DCCP_PKT_DATA) /* RFC 4340, 6 */ 133cf86314cSGerrit Renker break; 134e77b8363SGerrit Renker rc = dccp_feat_parse_options(sk, dreq, mandatory, opt, 135e77b8363SGerrit Renker *value, value + 1, len - 1); 136e77b8363SGerrit Renker if (rc) 137e77b8363SGerrit Renker goto out_featneg_failed; 138410e27a4SGerrit Renker break; 139410e27a4SGerrit Renker case DCCPO_ACK_VECTOR_0: 140410e27a4SGerrit Renker case DCCPO_ACK_VECTOR_1: 141410e27a4SGerrit Renker if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ 142410e27a4SGerrit Renker break; 1436fdd34d4SGerrit Renker if (dp->dccps_hc_rx_ackvec != NULL && 144410e27a4SGerrit Renker dccp_ackvec_parse(sk, skb, &ackno, opt, value, len)) 145410e27a4SGerrit Renker goto out_invalid_option; 146afe00251SAndrea Bittau break; 1477c657876SArnaldo Carvalho de Melo case DCCPO_TIMESTAMP: 1487c657876SArnaldo Carvalho de Melo if (len != 4) 1497c657876SArnaldo Carvalho de Melo goto out_invalid_option; 150b4d4f7c7SGerrit Renker /* 151b4d4f7c7SGerrit Renker * RFC 4340 13.1: "The precise time corresponding to 152b4d4f7c7SGerrit Renker * Timestamp Value zero is not specified". We use 153b4d4f7c7SGerrit Renker * zero to indicate absence of a meaningful timestamp. 154b4d4f7c7SGerrit Renker */ 15576fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 156b4d4f7c7SGerrit Renker if (unlikely(opt_val == 0)) { 157b4d4f7c7SGerrit Renker DCCP_WARN("Timestamp with zero value\n"); 158b4d4f7c7SGerrit Renker break; 159b4d4f7c7SGerrit Renker } 1607c657876SArnaldo Carvalho de Melo 161b4d4f7c7SGerrit Renker if (dreq != NULL) { 162b4d4f7c7SGerrit Renker dreq->dreq_timestamp_echo = ntohl(opt_val); 163b4d4f7c7SGerrit Renker dreq->dreq_timestamp_time = dccp_timestamp(); 164b4d4f7c7SGerrit Renker } else { 165b4d4f7c7SGerrit Renker opt_recv->dccpor_timestamp = 166b4d4f7c7SGerrit Renker dp->dccps_timestamp_echo = ntohl(opt_val); 167b4d4f7c7SGerrit Renker dp->dccps_timestamp_time = dccp_timestamp(); 168b4d4f7c7SGerrit Renker } 16909dbc389SGerrit Renker dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", 170b4d4f7c7SGerrit Renker dccp_role(sk), ntohl(opt_val), 171f6ccf554SDavid S. Miller (unsigned long long) 1727c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_ack_seq); 1737c657876SArnaldo Carvalho de Melo break; 1747c657876SArnaldo Carvalho de Melo case DCCPO_TIMESTAMP_ECHO: 1751bc09869SIan McDonald if (len != 4 && len != 6 && len != 8) 1767c657876SArnaldo Carvalho de Melo goto out_invalid_option; 1777c657876SArnaldo Carvalho de Melo 17876fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 17976fd1e87SGerrit Renker opt_recv->dccpor_timestamp_echo = ntohl(opt_val); 1807c657876SArnaldo Carvalho de Melo 18109dbc389SGerrit Renker dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, " 182f73f7097SGerrit Renker "ackno=%llu", dccp_role(sk), 1837690af3fSArnaldo Carvalho de Melo opt_recv->dccpor_timestamp_echo, 184f6ccf554SDavid S. Miller len + 2, 185f6ccf554SDavid S. Miller (unsigned long long) 1861bc09869SIan McDonald DCCP_SKB_CB(skb)->dccpd_ack_seq); 1877c657876SArnaldo Carvalho de Melo 18876fd1e87SGerrit Renker value += 4; 1891bc09869SIan McDonald 19076fd1e87SGerrit Renker if (len == 4) { /* no elapsed time included */ 191f73f7097SGerrit Renker dccp_pr_debug_cat("\n"); 1921c14ac0aSArnaldo Carvalho de Melo break; 193f73f7097SGerrit Renker } 1941c14ac0aSArnaldo Carvalho de Melo 19576fd1e87SGerrit Renker if (len == 6) { /* 2-byte elapsed time */ 19676fd1e87SGerrit Renker __be16 opt_val2 = get_unaligned((__be16 *)value); 19776fd1e87SGerrit Renker elapsed_time = ntohs(opt_val2); 19876fd1e87SGerrit Renker } else { /* 4-byte elapsed time */ 19976fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 20076fd1e87SGerrit Renker elapsed_time = ntohl(opt_val); 20176fd1e87SGerrit Renker } 2021c14ac0aSArnaldo Carvalho de Melo 203dcad856fSGerrit Renker dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time); 204f73f7097SGerrit Renker 2051c14ac0aSArnaldo Carvalho de Melo /* Give precedence to the biggest ELAPSED_TIME */ 2061c14ac0aSArnaldo Carvalho de Melo if (elapsed_time > opt_recv->dccpor_elapsed_time) 2071c14ac0aSArnaldo Carvalho de Melo opt_recv->dccpor_elapsed_time = elapsed_time; 2087c657876SArnaldo Carvalho de Melo break; 2097c657876SArnaldo Carvalho de Melo case DCCPO_ELAPSED_TIME: 210c86ab2b6SGerrit Renker if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ 211c86ab2b6SGerrit Renker break; 2121bc09869SIan McDonald 21376fd1e87SGerrit Renker if (len == 2) { 21476fd1e87SGerrit Renker __be16 opt_val2 = get_unaligned((__be16 *)value); 21576fd1e87SGerrit Renker elapsed_time = ntohs(opt_val2); 216c86ab2b6SGerrit Renker } else if (len == 4) { 21776fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 21876fd1e87SGerrit Renker elapsed_time = ntohl(opt_val); 219c86ab2b6SGerrit Renker } else { 220c86ab2b6SGerrit Renker goto out_invalid_option; 22176fd1e87SGerrit Renker } 2221c14ac0aSArnaldo Carvalho de Melo 2231c14ac0aSArnaldo Carvalho de Melo if (elapsed_time > opt_recv->dccpor_elapsed_time) 2241c14ac0aSArnaldo Carvalho de Melo opt_recv->dccpor_elapsed_time = elapsed_time; 2251bc09869SIan McDonald 22609dbc389SGerrit Renker dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", 22709dbc389SGerrit Renker dccp_role(sk), elapsed_time); 2287c657876SArnaldo Carvalho de Melo break; 229410e27a4SGerrit Renker case 128 ... 191: { 230410e27a4SGerrit Renker const u16 idx = value - options; 231410e27a4SGerrit Renker 2327690af3fSArnaldo Carvalho de Melo if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk, 233410e27a4SGerrit Renker opt, len, idx, 234410e27a4SGerrit Renker value) != 0) 2357c657876SArnaldo Carvalho de Melo goto out_invalid_option; 236410e27a4SGerrit Renker } 2377c657876SArnaldo Carvalho de Melo break; 238410e27a4SGerrit Renker case 192 ... 255: { 239410e27a4SGerrit Renker const u16 idx = value - options; 240410e27a4SGerrit Renker 2417690af3fSArnaldo Carvalho de Melo if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk, 242410e27a4SGerrit Renker opt, len, idx, 243410e27a4SGerrit Renker value) != 0) 2447c657876SArnaldo Carvalho de Melo goto out_invalid_option; 245410e27a4SGerrit Renker } 2467c657876SArnaldo Carvalho de Melo break; 2477c657876SArnaldo Carvalho de Melo default: 24859348b19SGerrit Renker DCCP_CRIT("DCCP(%p): option %d(len=%d) not " 24959348b19SGerrit Renker "implemented, ignoring", sk, opt, len); 2507c657876SArnaldo Carvalho de Melo break; 2517c657876SArnaldo Carvalho de Melo } 2528b819412SGerrit Renker ignore_option: 253afe00251SAndrea Bittau if (opt != DCCPO_MANDATORY) 254afe00251SAndrea Bittau mandatory = 0; 2557c657876SArnaldo Carvalho de Melo } 2567c657876SArnaldo Carvalho de Melo 2576df9424aSArnaldo Carvalho de Melo /* mandatory was the last byte in option list -> reset connection */ 2586df9424aSArnaldo Carvalho de Melo if (mandatory) 2596df9424aSArnaldo Carvalho de Melo goto out_invalid_option; 2606df9424aSArnaldo Carvalho de Melo 261faf61c33SGerrit Renker out_nonsensical_length: 262faf61c33SGerrit Renker /* RFC 4340, 5.8: ignore option and all remaining option space */ 2637c657876SArnaldo Carvalho de Melo return 0; 2647c657876SArnaldo Carvalho de Melo 2657c657876SArnaldo Carvalho de Melo out_invalid_option: 2667c657876SArnaldo Carvalho de Melo DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT); 267e77b8363SGerrit Renker rc = DCCP_RESET_CODE_OPTION_ERROR; 268e77b8363SGerrit Renker out_featneg_failed: 269e77b8363SGerrit Renker DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc); 270e77b8363SGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_code = rc; 271eac7726bSGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt; 272eac7726bSGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0; 273eac7726bSGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0; 2747c657876SArnaldo Carvalho de Melo return -1; 2757c657876SArnaldo Carvalho de Melo } 2767c657876SArnaldo Carvalho de Melo 277b61fafc4SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_parse_options); 278b61fafc4SArnaldo Carvalho de Melo 27902fa460eSGerrit Renker void dccp_encode_value_var(const u64 value, u8 *to, const u8 len) 2807c657876SArnaldo Carvalho de Melo { 28102fa460eSGerrit Renker if (len >= DCCP_OPTVAL_MAXLEN) 28202fa460eSGerrit Renker *to++ = (value & 0xFF0000000000ull) >> 40; 28302fa460eSGerrit Renker if (len > 4) 28402fa460eSGerrit Renker *to++ = (value & 0xFF00000000ull) >> 32; 2857c657876SArnaldo Carvalho de Melo if (len > 3) 2867c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF000000) >> 24; 2877c657876SArnaldo Carvalho de Melo if (len > 2) 2887c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF0000) >> 16; 2897c657876SArnaldo Carvalho de Melo if (len > 1) 2907c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF00) >> 8; 2917c657876SArnaldo Carvalho de Melo if (len > 0) 2927c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF); 2937c657876SArnaldo Carvalho de Melo } 2947c657876SArnaldo Carvalho de Melo 2955b5d0e70SGerrit Renker static inline u8 dccp_ndp_len(const u64 ndp) 2967c657876SArnaldo Carvalho de Melo { 2975b5d0e70SGerrit Renker if (likely(ndp <= 0xFF)) 2985b5d0e70SGerrit Renker return 1; 2994be929beSAlexey Dobriyan return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6); 3007c657876SArnaldo Carvalho de Melo } 3017c657876SArnaldo Carvalho de Melo 302a7d13fbfSGerrit Renker int dccp_insert_option(struct sk_buff *skb, const unsigned char option, 3037c657876SArnaldo Carvalho de Melo const void *value, const unsigned char len) 3047c657876SArnaldo Carvalho de Melo { 3057c657876SArnaldo Carvalho de Melo unsigned char *to; 3067c657876SArnaldo Carvalho de Melo 3072d0817d1SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) 3082d0817d1SArnaldo Carvalho de Melo return -1; 3097c657876SArnaldo Carvalho de Melo 3107c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2; 3117c657876SArnaldo Carvalho de Melo 3127c657876SArnaldo Carvalho de Melo to = skb_push(skb, len + 2); 3137c657876SArnaldo Carvalho de Melo *to++ = option; 3147c657876SArnaldo Carvalho de Melo *to++ = len + 2; 3157c657876SArnaldo Carvalho de Melo 3167c657876SArnaldo Carvalho de Melo memcpy(to, value, len); 3172d0817d1SArnaldo Carvalho de Melo return 0; 3187c657876SArnaldo Carvalho de Melo } 3197c657876SArnaldo Carvalho de Melo 3207c657876SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_insert_option); 3217c657876SArnaldo Carvalho de Melo 3222d0817d1SArnaldo Carvalho de Melo static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) 3237c657876SArnaldo Carvalho de Melo { 3247c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 3255b5d0e70SGerrit Renker u64 ndp = dp->dccps_ndp_count; 3267c657876SArnaldo Carvalho de Melo 3277c657876SArnaldo Carvalho de Melo if (dccp_non_data_packet(skb)) 3287c657876SArnaldo Carvalho de Melo ++dp->dccps_ndp_count; 3297c657876SArnaldo Carvalho de Melo else 3307c657876SArnaldo Carvalho de Melo dp->dccps_ndp_count = 0; 3317c657876SArnaldo Carvalho de Melo 3327c657876SArnaldo Carvalho de Melo if (ndp > 0) { 3337c657876SArnaldo Carvalho de Melo unsigned char *ptr; 3347c657876SArnaldo Carvalho de Melo const int ndp_len = dccp_ndp_len(ndp); 3357c657876SArnaldo Carvalho de Melo const int len = ndp_len + 2; 3367c657876SArnaldo Carvalho de Melo 3377c657876SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) 3382d0817d1SArnaldo Carvalho de Melo return -1; 3397c657876SArnaldo Carvalho de Melo 3407c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len; 3417c657876SArnaldo Carvalho de Melo 3427c657876SArnaldo Carvalho de Melo ptr = skb_push(skb, len); 3437c657876SArnaldo Carvalho de Melo *ptr++ = DCCPO_NDP_COUNT; 3447c657876SArnaldo Carvalho de Melo *ptr++ = len; 3457c657876SArnaldo Carvalho de Melo dccp_encode_value_var(ndp, ptr, ndp_len); 3467c657876SArnaldo Carvalho de Melo } 3472d0817d1SArnaldo Carvalho de Melo 3482d0817d1SArnaldo Carvalho de Melo return 0; 3497c657876SArnaldo Carvalho de Melo } 3507c657876SArnaldo Carvalho de Melo 3517c657876SArnaldo Carvalho de Melo static inline int dccp_elapsed_time_len(const u32 elapsed_time) 3527c657876SArnaldo Carvalho de Melo { 353b1c9fe7bSIan McDonald return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; 3547c657876SArnaldo Carvalho de Melo } 3557c657876SArnaldo Carvalho de Melo 356a7d13fbfSGerrit Renker int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time) 3577c657876SArnaldo Carvalho de Melo { 3587c657876SArnaldo Carvalho de Melo const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); 3597c657876SArnaldo Carvalho de Melo const int len = 2 + elapsed_time_len; 3607c657876SArnaldo Carvalho de Melo unsigned char *to; 3617c657876SArnaldo Carvalho de Melo 3621bc09869SIan McDonald if (elapsed_time_len == 0) 3632d0817d1SArnaldo Carvalho de Melo return 0; 3647c657876SArnaldo Carvalho de Melo 3652d0817d1SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) 3662d0817d1SArnaldo Carvalho de Melo return -1; 3677c657876SArnaldo Carvalho de Melo 3687c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len; 3697c657876SArnaldo Carvalho de Melo 3707c657876SArnaldo Carvalho de Melo to = skb_push(skb, len); 3717c657876SArnaldo Carvalho de Melo *to++ = DCCPO_ELAPSED_TIME; 3727c657876SArnaldo Carvalho de Melo *to++ = len; 3737c657876SArnaldo Carvalho de Melo 3741bc09869SIan McDonald if (elapsed_time_len == 2) { 37560fe62e7SAndrea Bittau const __be16 var16 = htons((u16)elapsed_time); 3761bc09869SIan McDonald memcpy(to, &var16, 2); 3771bc09869SIan McDonald } else { 37860fe62e7SAndrea Bittau const __be32 var32 = htonl(elapsed_time); 3791bc09869SIan McDonald memcpy(to, &var32, 4); 3801bc09869SIan McDonald } 3817c657876SArnaldo Carvalho de Melo 3822d0817d1SArnaldo Carvalho de Melo return 0; 3837c657876SArnaldo Carvalho de Melo } 3847c657876SArnaldo Carvalho de Melo 385d4b81ff7SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); 3867c657876SArnaldo Carvalho de Melo 387a7d13fbfSGerrit Renker int dccp_insert_option_timestamp(struct sk_buff *skb) 3887c657876SArnaldo Carvalho de Melo { 3894c70f383SGerrit Renker __be32 now = htonl(dccp_timestamp()); 3901bc09869SIan McDonald /* yes this will overflow but that is the point as we want a 3911bc09869SIan McDonald * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ 3921bc09869SIan McDonald 393a7d13fbfSGerrit Renker return dccp_insert_option(skb, DCCPO_TIMESTAMP, &now, sizeof(now)); 3947c657876SArnaldo Carvalho de Melo } 3957c657876SArnaldo Carvalho de Melo 396d4b81ff7SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp); 397d4b81ff7SArnaldo Carvalho de Melo 398b4d4f7c7SGerrit Renker static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, 399b4d4f7c7SGerrit Renker struct dccp_request_sock *dreq, 4007690af3fSArnaldo Carvalho de Melo struct sk_buff *skb) 4017c657876SArnaldo Carvalho de Melo { 40260fe62e7SAndrea Bittau __be32 tstamp_echo; 4037c657876SArnaldo Carvalho de Melo unsigned char *to; 404b4d4f7c7SGerrit Renker u32 elapsed_time, elapsed_time_len, len; 405b4d4f7c7SGerrit Renker 406b4d4f7c7SGerrit Renker if (dreq != NULL) { 407b4d4f7c7SGerrit Renker elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; 408b4d4f7c7SGerrit Renker tstamp_echo = htonl(dreq->dreq_timestamp_echo); 409b4d4f7c7SGerrit Renker dreq->dreq_timestamp_echo = 0; 410b4d4f7c7SGerrit Renker } else { 411b4d4f7c7SGerrit Renker elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; 412b4d4f7c7SGerrit Renker tstamp_echo = htonl(dp->dccps_timestamp_echo); 413b4d4f7c7SGerrit Renker dp->dccps_timestamp_echo = 0; 414b4d4f7c7SGerrit Renker } 415b4d4f7c7SGerrit Renker 416b0e56780SArnaldo Carvalho de Melo elapsed_time_len = dccp_elapsed_time_len(elapsed_time); 417b0e56780SArnaldo Carvalho de Melo len = 6 + elapsed_time_len; 418b0e56780SArnaldo Carvalho de Melo 4192d0817d1SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) 4202d0817d1SArnaldo Carvalho de Melo return -1; 4217c657876SArnaldo Carvalho de Melo 4227c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len; 4237c657876SArnaldo Carvalho de Melo 4247c657876SArnaldo Carvalho de Melo to = skb_push(skb, len); 4257c657876SArnaldo Carvalho de Melo *to++ = DCCPO_TIMESTAMP_ECHO; 4267c657876SArnaldo Carvalho de Melo *to++ = len; 4277c657876SArnaldo Carvalho de Melo 4287c657876SArnaldo Carvalho de Melo memcpy(to, &tstamp_echo, 4); 4297c657876SArnaldo Carvalho de Melo to += 4; 4301bc09869SIan McDonald 4311bc09869SIan McDonald if (elapsed_time_len == 2) { 43260fe62e7SAndrea Bittau const __be16 var16 = htons((u16)elapsed_time); 4331bc09869SIan McDonald memcpy(to, &var16, 2); 4341bc09869SIan McDonald } else if (elapsed_time_len == 4) { 43560fe62e7SAndrea Bittau const __be32 var32 = htonl(elapsed_time); 4361bc09869SIan McDonald memcpy(to, &var32, 4); 4371bc09869SIan McDonald } 4387c657876SArnaldo Carvalho de Melo 4392d0817d1SArnaldo Carvalho de Melo return 0; 4407c657876SArnaldo Carvalho de Melo } 4417c657876SArnaldo Carvalho de Melo 442d3710566SGerrit Renker /** 443d3710566SGerrit Renker * dccp_insert_option_mandatory - Mandatory option (5.8.2) 444d3710566SGerrit Renker * Note that since we are using skb_push, this function needs to be called 445d3710566SGerrit Renker * _after_ inserting the option it is supposed to influence (stack order). 446d3710566SGerrit Renker */ 447d3710566SGerrit Renker int dccp_insert_option_mandatory(struct sk_buff *skb) 448d3710566SGerrit Renker { 449d3710566SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN) 450d3710566SGerrit Renker return -1; 451d3710566SGerrit Renker 452d3710566SGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len++; 453d3710566SGerrit Renker *skb_push(skb, 1) = DCCPO_MANDATORY; 454d3710566SGerrit Renker return 0; 455d3710566SGerrit Renker } 456d3710566SGerrit Renker 4578c862c23SGerrit Renker /** 4588c862c23SGerrit Renker * dccp_insert_fn_opt - Insert single Feature-Negotiation option into @skb 4598c862c23SGerrit Renker * @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R 4608c862c23SGerrit Renker * @feat: one out of %dccp_feature_numbers 4618c862c23SGerrit Renker * @val: NN value or SP array (preferred element first) to copy 4628c862c23SGerrit Renker * @len: true length of @val in bytes (excluding first element repetition) 4638c862c23SGerrit Renker * @repeat_first: whether to copy the first element of @val twice 4648c862c23SGerrit Renker * The last argument is used to construct Confirm options, where the preferred 4658c862c23SGerrit Renker * value and the preference list appear separately (RFC 4340, 6.3.1). Preference 4668c862c23SGerrit Renker * lists are kept such that the preferred entry is always first, so we only need 4678c862c23SGerrit Renker * to copy twice, and avoid the overhead of cloning into a bigger array. 4688c862c23SGerrit Renker */ 4698c862c23SGerrit Renker int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat, 4708c862c23SGerrit Renker u8 *val, u8 len, bool repeat_first) 4714829007cSGerrit Renker { 4728c862c23SGerrit Renker u8 tot_len, *to; 4734829007cSGerrit Renker 4748c862c23SGerrit Renker /* take the `Feature' field and possible repetition into account */ 4758c862c23SGerrit Renker if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) { 4768c862c23SGerrit Renker DCCP_WARN("length %u for feature %u too large\n", len, feat); 477cf9ddf73SGerrit Renker return -1; 478cf9ddf73SGerrit Renker } 479cf9ddf73SGerrit Renker 4808c862c23SGerrit Renker if (unlikely(val == NULL || len == 0)) 4818c862c23SGerrit Renker len = repeat_first = 0; 4828c862c23SGerrit Renker tot_len = 3 + repeat_first + len; 483410e27a4SGerrit Renker 4848c862c23SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) { 4858c862c23SGerrit Renker DCCP_WARN("packet too small for feature %d option!\n", feat); 4868c862c23SGerrit Renker return -1; 4878c862c23SGerrit Renker } 4888c862c23SGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len; 4898c862c23SGerrit Renker 4908c862c23SGerrit Renker to = skb_push(skb, tot_len); 491afe00251SAndrea Bittau *to++ = type; 4928c862c23SGerrit Renker *to++ = tot_len; 493afe00251SAndrea Bittau *to++ = feat; 494afe00251SAndrea Bittau 4958c862c23SGerrit Renker if (repeat_first) 4968c862c23SGerrit Renker *to++ = *val; 497afe00251SAndrea Bittau if (len) 498afe00251SAndrea Bittau memcpy(to, val, len); 499410e27a4SGerrit Renker return 0; 500410e27a4SGerrit Renker } 501410e27a4SGerrit Renker 502af3b867eSGerrit Renker /* The length of all options needs to be a multiple of 4 (5.8) */ 503af3b867eSGerrit Renker static void dccp_insert_option_padding(struct sk_buff *skb) 504af3b867eSGerrit Renker { 505af3b867eSGerrit Renker int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; 506af3b867eSGerrit Renker 507af3b867eSGerrit Renker if (padding != 0) { 508af3b867eSGerrit Renker padding = 4 - padding; 509af3b867eSGerrit Renker memset(skb_push(skb, padding), 0, padding); 510af3b867eSGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len += padding; 511af3b867eSGerrit Renker } 512af3b867eSGerrit Renker } 513af3b867eSGerrit Renker 5142d0817d1SArnaldo Carvalho de Melo int dccp_insert_options(struct sock *sk, struct sk_buff *skb) 5157c657876SArnaldo Carvalho de Melo { 5167c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 5177c657876SArnaldo Carvalho de Melo 5187c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len = 0; 5197c657876SArnaldo Carvalho de Melo 5204098dce5SGerrit Renker if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb)) 5212d0817d1SArnaldo Carvalho de Melo return -1; 5227c657876SArnaldo Carvalho de Melo 5238b7b6c75SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) { 5248b7b6c75SGerrit Renker 5258b7b6c75SGerrit Renker /* Feature Negotiation */ 5268b7b6c75SGerrit Renker if (dccp_feat_insert_opts(dp, NULL, skb)) 5272d0817d1SArnaldo Carvalho de Melo return -1; 5288b7b6c75SGerrit Renker 5298b7b6c75SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) { 5308b7b6c75SGerrit Renker /* 5318b7b6c75SGerrit Renker * Obtain RTT sample from Request/Response exchange. 532*59b80802SGerrit Renker * This is currently used for TFRC initialisation. 5338b7b6c75SGerrit Renker */ 534a7d13fbfSGerrit Renker if (dccp_insert_option_timestamp(skb)) 5358b7b6c75SGerrit Renker return -1; 5368b7b6c75SGerrit Renker 5376fdd34d4SGerrit Renker } else if (dp->dccps_hc_rx_ackvec != NULL && 5388b7b6c75SGerrit Renker dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) && 5398b7b6c75SGerrit Renker dccp_insert_option_ackvec(sk, skb)) { 5408b7b6c75SGerrit Renker return -1; 5418b7b6c75SGerrit Renker } 5427c657876SArnaldo Carvalho de Melo } 5437c657876SArnaldo Carvalho de Melo 544507d37cfSArnaldo Carvalho de Melo if (dp->dccps_hc_rx_insert_options) { 5452d0817d1SArnaldo Carvalho de Melo if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb)) 5462d0817d1SArnaldo Carvalho de Melo return -1; 547507d37cfSArnaldo Carvalho de Melo dp->dccps_hc_rx_insert_options = 0; 548507d37cfSArnaldo Carvalho de Melo } 5497c657876SArnaldo Carvalho de Melo 550b4d4f7c7SGerrit Renker if (dp->dccps_timestamp_echo != 0 && 551b4d4f7c7SGerrit Renker dccp_insert_option_timestamp_echo(dp, NULL, skb)) 552b4d4f7c7SGerrit Renker return -1; 553b4d4f7c7SGerrit Renker 554af3b867eSGerrit Renker dccp_insert_option_padding(skb); 555af3b867eSGerrit Renker return 0; 5567c657876SArnaldo Carvalho de Melo } 5572d0817d1SArnaldo Carvalho de Melo 558af3b867eSGerrit Renker int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) 559af3b867eSGerrit Renker { 560af3b867eSGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len = 0; 561af3b867eSGerrit Renker 5628b7b6c75SGerrit Renker if (dccp_feat_insert_opts(NULL, dreq, skb)) 5638b7b6c75SGerrit Renker return -1; 5648b7b6c75SGerrit Renker 565*59b80802SGerrit Renker /* Obtain RTT sample from Response/Ack exchange (used by TFRC). */ 566*59b80802SGerrit Renker if (dccp_insert_option_timestamp(skb)) 567*59b80802SGerrit Renker return -1; 568*59b80802SGerrit Renker 569af3b867eSGerrit Renker if (dreq->dreq_timestamp_echo != 0 && 570af3b867eSGerrit Renker dccp_insert_option_timestamp_echo(NULL, dreq, skb)) 571af3b867eSGerrit Renker return -1; 572af3b867eSGerrit Renker 573af3b867eSGerrit Renker dccp_insert_option_padding(skb); 5742d0817d1SArnaldo Carvalho de Melo return 0; 5757c657876SArnaldo Carvalho de Melo } 576