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 /* 998b819412SGerrit Renker * CCID-specific options are ignored during connection setup, as 1008b819412SGerrit Renker * negotiation may still be in progress (see RFC 4340, 10.3). 10165907a43SGerrit Renker * The same applies to Ack Vectors, as these depend on the CCID. 1028b819412SGerrit Renker */ 103a18213d1SGerrit Renker if (dreq != NULL && (opt >= DCCPO_MIN_RX_CCID_SPECIFIC || 10465907a43SGerrit Renker opt == DCCPO_ACK_VECTOR_0 || opt == DCCPO_ACK_VECTOR_1)) 1058b819412SGerrit Renker goto ignore_option; 1068b819412SGerrit Renker 1077c657876SArnaldo Carvalho de Melo switch (opt) { 1087c657876SArnaldo Carvalho de Melo case DCCPO_PADDING: 1097c657876SArnaldo Carvalho de Melo break; 110afe00251SAndrea Bittau case DCCPO_MANDATORY: 111afe00251SAndrea Bittau if (mandatory) 112afe00251SAndrea Bittau goto out_invalid_option; 1136df9424aSArnaldo Carvalho de Melo if (pkt_type != DCCP_PKT_DATA) 114afe00251SAndrea Bittau mandatory = 1; 115afe00251SAndrea Bittau break; 1167c657876SArnaldo Carvalho de Melo case DCCPO_NDP_COUNT: 1175b5d0e70SGerrit Renker if (len > 6) 1187c657876SArnaldo Carvalho de Melo goto out_invalid_option; 1197c657876SArnaldo Carvalho de Melo 1207c657876SArnaldo Carvalho de Melo opt_recv->dccpor_ndp = dccp_decode_value_var(value, len); 1215b5d0e70SGerrit Renker dccp_pr_debug("%s opt: NDP count=%llu\n", dccp_role(sk), 1225b5d0e70SGerrit Renker (unsigned long long)opt_recv->dccpor_ndp); 1237c657876SArnaldo Carvalho de Melo break; 124b1ad0042SGerrit Renker case DCCPO_CHANGE_L ... DCCPO_CONFIRM_R: 125b1ad0042SGerrit Renker if (pkt_type == DCCP_PKT_DATA) /* RFC 4340, 6 */ 126cf86314cSGerrit Renker break; 127e77b8363SGerrit Renker rc = dccp_feat_parse_options(sk, dreq, mandatory, opt, 128e77b8363SGerrit Renker *value, value + 1, len - 1); 129e77b8363SGerrit Renker if (rc) 130e77b8363SGerrit Renker goto out_featneg_failed; 131410e27a4SGerrit Renker break; 132410e27a4SGerrit Renker case DCCPO_ACK_VECTOR_0: 133410e27a4SGerrit Renker case DCCPO_ACK_VECTOR_1: 134410e27a4SGerrit Renker if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ 135410e27a4SGerrit Renker break; 1366fdd34d4SGerrit Renker if (dp->dccps_hc_rx_ackvec != NULL && 137410e27a4SGerrit Renker dccp_ackvec_parse(sk, skb, &ackno, opt, value, len)) 138410e27a4SGerrit Renker goto out_invalid_option; 139afe00251SAndrea Bittau break; 1407c657876SArnaldo Carvalho de Melo case DCCPO_TIMESTAMP: 1417c657876SArnaldo Carvalho de Melo if (len != 4) 1427c657876SArnaldo Carvalho de Melo goto out_invalid_option; 143b4d4f7c7SGerrit Renker /* 144b4d4f7c7SGerrit Renker * RFC 4340 13.1: "The precise time corresponding to 145b4d4f7c7SGerrit Renker * Timestamp Value zero is not specified". We use 146b4d4f7c7SGerrit Renker * zero to indicate absence of a meaningful timestamp. 147b4d4f7c7SGerrit Renker */ 14876fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 149b4d4f7c7SGerrit Renker if (unlikely(opt_val == 0)) { 150b4d4f7c7SGerrit Renker DCCP_WARN("Timestamp with zero value\n"); 151b4d4f7c7SGerrit Renker break; 152b4d4f7c7SGerrit Renker } 1537c657876SArnaldo Carvalho de Melo 154b4d4f7c7SGerrit Renker if (dreq != NULL) { 155b4d4f7c7SGerrit Renker dreq->dreq_timestamp_echo = ntohl(opt_val); 156b4d4f7c7SGerrit Renker dreq->dreq_timestamp_time = dccp_timestamp(); 157b4d4f7c7SGerrit Renker } else { 158b4d4f7c7SGerrit Renker opt_recv->dccpor_timestamp = 159b4d4f7c7SGerrit Renker dp->dccps_timestamp_echo = ntohl(opt_val); 160b4d4f7c7SGerrit Renker dp->dccps_timestamp_time = dccp_timestamp(); 161b4d4f7c7SGerrit Renker } 16209dbc389SGerrit Renker dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", 163b4d4f7c7SGerrit Renker dccp_role(sk), ntohl(opt_val), 164f6ccf554SDavid S. Miller (unsigned long long) 1657c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_ack_seq); 166*ecdfbdabSGerrit Renker /* schedule an Ack in case this sender is quiescent */ 167*ecdfbdabSGerrit Renker inet_csk_schedule_ack(sk); 1687c657876SArnaldo Carvalho de Melo break; 1697c657876SArnaldo Carvalho de Melo case DCCPO_TIMESTAMP_ECHO: 1701bc09869SIan McDonald if (len != 4 && len != 6 && len != 8) 1717c657876SArnaldo Carvalho de Melo goto out_invalid_option; 1727c657876SArnaldo Carvalho de Melo 17376fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 17476fd1e87SGerrit Renker opt_recv->dccpor_timestamp_echo = ntohl(opt_val); 1757c657876SArnaldo Carvalho de Melo 17609dbc389SGerrit Renker dccp_pr_debug("%s rx opt: TIMESTAMP_ECHO=%u, len=%d, " 177f73f7097SGerrit Renker "ackno=%llu", dccp_role(sk), 1787690af3fSArnaldo Carvalho de Melo opt_recv->dccpor_timestamp_echo, 179f6ccf554SDavid S. Miller len + 2, 180f6ccf554SDavid S. Miller (unsigned long long) 1811bc09869SIan McDonald DCCP_SKB_CB(skb)->dccpd_ack_seq); 1827c657876SArnaldo Carvalho de Melo 18376fd1e87SGerrit Renker value += 4; 1841bc09869SIan McDonald 18576fd1e87SGerrit Renker if (len == 4) { /* no elapsed time included */ 186f73f7097SGerrit Renker dccp_pr_debug_cat("\n"); 1871c14ac0aSArnaldo Carvalho de Melo break; 188f73f7097SGerrit Renker } 1891c14ac0aSArnaldo Carvalho de Melo 19076fd1e87SGerrit Renker if (len == 6) { /* 2-byte elapsed time */ 19176fd1e87SGerrit Renker __be16 opt_val2 = get_unaligned((__be16 *)value); 19276fd1e87SGerrit Renker elapsed_time = ntohs(opt_val2); 19376fd1e87SGerrit Renker } else { /* 4-byte elapsed time */ 19476fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 19576fd1e87SGerrit Renker elapsed_time = ntohl(opt_val); 19676fd1e87SGerrit Renker } 1971c14ac0aSArnaldo Carvalho de Melo 198dcad856fSGerrit Renker dccp_pr_debug_cat(", ELAPSED_TIME=%u\n", elapsed_time); 199f73f7097SGerrit Renker 2001c14ac0aSArnaldo Carvalho de Melo /* Give precedence to the biggest ELAPSED_TIME */ 2011c14ac0aSArnaldo Carvalho de Melo if (elapsed_time > opt_recv->dccpor_elapsed_time) 2021c14ac0aSArnaldo Carvalho de Melo opt_recv->dccpor_elapsed_time = elapsed_time; 2037c657876SArnaldo Carvalho de Melo break; 2047c657876SArnaldo Carvalho de Melo case DCCPO_ELAPSED_TIME: 205c86ab2b6SGerrit Renker if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ 206c86ab2b6SGerrit Renker break; 2071bc09869SIan McDonald 20876fd1e87SGerrit Renker if (len == 2) { 20976fd1e87SGerrit Renker __be16 opt_val2 = get_unaligned((__be16 *)value); 21076fd1e87SGerrit Renker elapsed_time = ntohs(opt_val2); 211c86ab2b6SGerrit Renker } else if (len == 4) { 21276fd1e87SGerrit Renker opt_val = get_unaligned((__be32 *)value); 21376fd1e87SGerrit Renker elapsed_time = ntohl(opt_val); 214c86ab2b6SGerrit Renker } else { 215c86ab2b6SGerrit Renker goto out_invalid_option; 21676fd1e87SGerrit Renker } 2171c14ac0aSArnaldo Carvalho de Melo 2181c14ac0aSArnaldo Carvalho de Melo if (elapsed_time > opt_recv->dccpor_elapsed_time) 2191c14ac0aSArnaldo Carvalho de Melo opt_recv->dccpor_elapsed_time = elapsed_time; 2201bc09869SIan McDonald 22109dbc389SGerrit Renker dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", 22209dbc389SGerrit Renker dccp_role(sk), elapsed_time); 2237c657876SArnaldo Carvalho de Melo break; 224a18213d1SGerrit Renker case DCCPO_MIN_RX_CCID_SPECIFIC ... DCCPO_MAX_RX_CCID_SPECIFIC: 2257690af3fSArnaldo Carvalho de Melo if (ccid_hc_rx_parse_options(dp->dccps_hc_rx_ccid, sk, 2264874c131SGerrit Renker pkt_type, opt, value, len)) 2277c657876SArnaldo Carvalho de Melo goto out_invalid_option; 2287c657876SArnaldo Carvalho de Melo break; 229a18213d1SGerrit Renker case DCCPO_MIN_TX_CCID_SPECIFIC ... DCCPO_MAX_TX_CCID_SPECIFIC: 2307690af3fSArnaldo Carvalho de Melo if (ccid_hc_tx_parse_options(dp->dccps_hc_tx_ccid, sk, 2314874c131SGerrit Renker pkt_type, opt, value, len)) 2327c657876SArnaldo Carvalho de Melo goto out_invalid_option; 2337c657876SArnaldo Carvalho de Melo break; 2347c657876SArnaldo Carvalho de Melo default: 23559348b19SGerrit Renker DCCP_CRIT("DCCP(%p): option %d(len=%d) not " 23659348b19SGerrit Renker "implemented, ignoring", sk, opt, len); 2377c657876SArnaldo Carvalho de Melo break; 2387c657876SArnaldo Carvalho de Melo } 2398b819412SGerrit Renker ignore_option: 240afe00251SAndrea Bittau if (opt != DCCPO_MANDATORY) 241afe00251SAndrea Bittau mandatory = 0; 2427c657876SArnaldo Carvalho de Melo } 2437c657876SArnaldo Carvalho de Melo 2446df9424aSArnaldo Carvalho de Melo /* mandatory was the last byte in option list -> reset connection */ 2456df9424aSArnaldo Carvalho de Melo if (mandatory) 2466df9424aSArnaldo Carvalho de Melo goto out_invalid_option; 2476df9424aSArnaldo Carvalho de Melo 248faf61c33SGerrit Renker out_nonsensical_length: 249faf61c33SGerrit Renker /* RFC 4340, 5.8: ignore option and all remaining option space */ 2507c657876SArnaldo Carvalho de Melo return 0; 2517c657876SArnaldo Carvalho de Melo 2527c657876SArnaldo Carvalho de Melo out_invalid_option: 2537c657876SArnaldo Carvalho de Melo DCCP_INC_STATS_BH(DCCP_MIB_INVALIDOPT); 254e77b8363SGerrit Renker rc = DCCP_RESET_CODE_OPTION_ERROR; 255e77b8363SGerrit Renker out_featneg_failed: 256e77b8363SGerrit Renker DCCP_WARN("DCCP(%p): Option %d (len=%d) error=%u\n", sk, opt, len, rc); 257e77b8363SGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_code = rc; 258eac7726bSGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_data[0] = opt; 259eac7726bSGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_data[1] = len > 0 ? value[0] : 0; 260eac7726bSGerrit Renker DCCP_SKB_CB(skb)->dccpd_reset_data[2] = len > 1 ? value[1] : 0; 2617c657876SArnaldo Carvalho de Melo return -1; 2627c657876SArnaldo Carvalho de Melo } 2637c657876SArnaldo Carvalho de Melo 264b61fafc4SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_parse_options); 265b61fafc4SArnaldo Carvalho de Melo 26602fa460eSGerrit Renker void dccp_encode_value_var(const u64 value, u8 *to, const u8 len) 2677c657876SArnaldo Carvalho de Melo { 26802fa460eSGerrit Renker if (len >= DCCP_OPTVAL_MAXLEN) 26902fa460eSGerrit Renker *to++ = (value & 0xFF0000000000ull) >> 40; 27002fa460eSGerrit Renker if (len > 4) 27102fa460eSGerrit Renker *to++ = (value & 0xFF00000000ull) >> 32; 2727c657876SArnaldo Carvalho de Melo if (len > 3) 2737c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF000000) >> 24; 2747c657876SArnaldo Carvalho de Melo if (len > 2) 2757c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF0000) >> 16; 2767c657876SArnaldo Carvalho de Melo if (len > 1) 2777c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF00) >> 8; 2787c657876SArnaldo Carvalho de Melo if (len > 0) 2797c657876SArnaldo Carvalho de Melo *to++ = (value & 0xFF); 2807c657876SArnaldo Carvalho de Melo } 2817c657876SArnaldo Carvalho de Melo 2825b5d0e70SGerrit Renker static inline u8 dccp_ndp_len(const u64 ndp) 2837c657876SArnaldo Carvalho de Melo { 2845b5d0e70SGerrit Renker if (likely(ndp <= 0xFF)) 2855b5d0e70SGerrit Renker return 1; 2864be929beSAlexey Dobriyan return likely(ndp <= USHRT_MAX) ? 2 : (ndp <= UINT_MAX ? 4 : 6); 2877c657876SArnaldo Carvalho de Melo } 2887c657876SArnaldo Carvalho de Melo 289a7d13fbfSGerrit Renker int dccp_insert_option(struct sk_buff *skb, const unsigned char option, 2907c657876SArnaldo Carvalho de Melo const void *value, const unsigned char len) 2917c657876SArnaldo Carvalho de Melo { 2927c657876SArnaldo Carvalho de Melo unsigned char *to; 2937c657876SArnaldo Carvalho de Melo 2942d0817d1SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 2 > DCCP_MAX_OPT_LEN) 2952d0817d1SArnaldo Carvalho de Melo return -1; 2967c657876SArnaldo Carvalho de Melo 2977c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len + 2; 2987c657876SArnaldo Carvalho de Melo 2997c657876SArnaldo Carvalho de Melo to = skb_push(skb, len + 2); 3007c657876SArnaldo Carvalho de Melo *to++ = option; 3017c657876SArnaldo Carvalho de Melo *to++ = len + 2; 3027c657876SArnaldo Carvalho de Melo 3037c657876SArnaldo Carvalho de Melo memcpy(to, value, len); 3042d0817d1SArnaldo Carvalho de Melo return 0; 3057c657876SArnaldo Carvalho de Melo } 3067c657876SArnaldo Carvalho de Melo 3077c657876SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_insert_option); 3087c657876SArnaldo Carvalho de Melo 3092d0817d1SArnaldo Carvalho de Melo static int dccp_insert_option_ndp(struct sock *sk, struct sk_buff *skb) 3107c657876SArnaldo Carvalho de Melo { 3117c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 3125b5d0e70SGerrit Renker u64 ndp = dp->dccps_ndp_count; 3137c657876SArnaldo Carvalho de Melo 3147c657876SArnaldo Carvalho de Melo if (dccp_non_data_packet(skb)) 3157c657876SArnaldo Carvalho de Melo ++dp->dccps_ndp_count; 3167c657876SArnaldo Carvalho de Melo else 3177c657876SArnaldo Carvalho de Melo dp->dccps_ndp_count = 0; 3187c657876SArnaldo Carvalho de Melo 3197c657876SArnaldo Carvalho de Melo if (ndp > 0) { 3207c657876SArnaldo Carvalho de Melo unsigned char *ptr; 3217c657876SArnaldo Carvalho de Melo const int ndp_len = dccp_ndp_len(ndp); 3227c657876SArnaldo Carvalho de Melo const int len = ndp_len + 2; 3237c657876SArnaldo Carvalho de Melo 3247c657876SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) 3252d0817d1SArnaldo Carvalho de Melo return -1; 3267c657876SArnaldo Carvalho de Melo 3277c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len; 3287c657876SArnaldo Carvalho de Melo 3297c657876SArnaldo Carvalho de Melo ptr = skb_push(skb, len); 3307c657876SArnaldo Carvalho de Melo *ptr++ = DCCPO_NDP_COUNT; 3317c657876SArnaldo Carvalho de Melo *ptr++ = len; 3327c657876SArnaldo Carvalho de Melo dccp_encode_value_var(ndp, ptr, ndp_len); 3337c657876SArnaldo Carvalho de Melo } 3342d0817d1SArnaldo Carvalho de Melo 3352d0817d1SArnaldo Carvalho de Melo return 0; 3367c657876SArnaldo Carvalho de Melo } 3377c657876SArnaldo Carvalho de Melo 3387c657876SArnaldo Carvalho de Melo static inline int dccp_elapsed_time_len(const u32 elapsed_time) 3397c657876SArnaldo Carvalho de Melo { 340b1c9fe7bSIan McDonald return elapsed_time == 0 ? 0 : elapsed_time <= 0xFFFF ? 2 : 4; 3417c657876SArnaldo Carvalho de Melo } 3427c657876SArnaldo Carvalho de Melo 343a7d13fbfSGerrit Renker int dccp_insert_option_elapsed_time(struct sk_buff *skb, u32 elapsed_time) 3447c657876SArnaldo Carvalho de Melo { 3457c657876SArnaldo Carvalho de Melo const int elapsed_time_len = dccp_elapsed_time_len(elapsed_time); 3467c657876SArnaldo Carvalho de Melo const int len = 2 + elapsed_time_len; 3477c657876SArnaldo Carvalho de Melo unsigned char *to; 3487c657876SArnaldo Carvalho de Melo 3491bc09869SIan McDonald if (elapsed_time_len == 0) 3502d0817d1SArnaldo Carvalho de Melo return 0; 3517c657876SArnaldo Carvalho de Melo 3522d0817d1SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) 3532d0817d1SArnaldo Carvalho de Melo return -1; 3547c657876SArnaldo Carvalho de Melo 3557c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len; 3567c657876SArnaldo Carvalho de Melo 3577c657876SArnaldo Carvalho de Melo to = skb_push(skb, len); 3587c657876SArnaldo Carvalho de Melo *to++ = DCCPO_ELAPSED_TIME; 3597c657876SArnaldo Carvalho de Melo *to++ = len; 3607c657876SArnaldo Carvalho de Melo 3611bc09869SIan McDonald if (elapsed_time_len == 2) { 36260fe62e7SAndrea Bittau const __be16 var16 = htons((u16)elapsed_time); 3631bc09869SIan McDonald memcpy(to, &var16, 2); 3641bc09869SIan McDonald } else { 36560fe62e7SAndrea Bittau const __be32 var32 = htonl(elapsed_time); 3661bc09869SIan McDonald memcpy(to, &var32, 4); 3671bc09869SIan McDonald } 3687c657876SArnaldo Carvalho de Melo 3692d0817d1SArnaldo Carvalho de Melo return 0; 3707c657876SArnaldo Carvalho de Melo } 3717c657876SArnaldo Carvalho de Melo 372d4b81ff7SArnaldo Carvalho de Melo EXPORT_SYMBOL_GPL(dccp_insert_option_elapsed_time); 3737c657876SArnaldo Carvalho de Melo 3741f4f0f64Sstephen hemminger static int dccp_insert_option_timestamp(struct sk_buff *skb) 3757c657876SArnaldo Carvalho de Melo { 3764c70f383SGerrit Renker __be32 now = htonl(dccp_timestamp()); 3771bc09869SIan McDonald /* yes this will overflow but that is the point as we want a 3781bc09869SIan McDonald * 10 usec 32 bit timer which mean it wraps every 11.9 hours */ 3791bc09869SIan McDonald 380a7d13fbfSGerrit Renker return dccp_insert_option(skb, DCCPO_TIMESTAMP, &now, sizeof(now)); 3817c657876SArnaldo Carvalho de Melo } 3827c657876SArnaldo Carvalho de Melo 383b4d4f7c7SGerrit Renker static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, 384b4d4f7c7SGerrit Renker struct dccp_request_sock *dreq, 3857690af3fSArnaldo Carvalho de Melo struct sk_buff *skb) 3867c657876SArnaldo Carvalho de Melo { 38760fe62e7SAndrea Bittau __be32 tstamp_echo; 3887c657876SArnaldo Carvalho de Melo unsigned char *to; 389b4d4f7c7SGerrit Renker u32 elapsed_time, elapsed_time_len, len; 390b4d4f7c7SGerrit Renker 391b4d4f7c7SGerrit Renker if (dreq != NULL) { 392b4d4f7c7SGerrit Renker elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; 393b4d4f7c7SGerrit Renker tstamp_echo = htonl(dreq->dreq_timestamp_echo); 394b4d4f7c7SGerrit Renker dreq->dreq_timestamp_echo = 0; 395b4d4f7c7SGerrit Renker } else { 396b4d4f7c7SGerrit Renker elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; 397b4d4f7c7SGerrit Renker tstamp_echo = htonl(dp->dccps_timestamp_echo); 398b4d4f7c7SGerrit Renker dp->dccps_timestamp_echo = 0; 399b4d4f7c7SGerrit Renker } 400b4d4f7c7SGerrit Renker 401b0e56780SArnaldo Carvalho de Melo elapsed_time_len = dccp_elapsed_time_len(elapsed_time); 402b0e56780SArnaldo Carvalho de Melo len = 6 + elapsed_time_len; 403b0e56780SArnaldo Carvalho de Melo 4042d0817d1SArnaldo Carvalho de Melo if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN) 4052d0817d1SArnaldo Carvalho de Melo return -1; 4067c657876SArnaldo Carvalho de Melo 4077c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len += len; 4087c657876SArnaldo Carvalho de Melo 4097c657876SArnaldo Carvalho de Melo to = skb_push(skb, len); 4107c657876SArnaldo Carvalho de Melo *to++ = DCCPO_TIMESTAMP_ECHO; 4117c657876SArnaldo Carvalho de Melo *to++ = len; 4127c657876SArnaldo Carvalho de Melo 4137c657876SArnaldo Carvalho de Melo memcpy(to, &tstamp_echo, 4); 4147c657876SArnaldo Carvalho de Melo to += 4; 4151bc09869SIan McDonald 4161bc09869SIan McDonald if (elapsed_time_len == 2) { 41760fe62e7SAndrea Bittau const __be16 var16 = htons((u16)elapsed_time); 4181bc09869SIan McDonald memcpy(to, &var16, 2); 4191bc09869SIan McDonald } else if (elapsed_time_len == 4) { 42060fe62e7SAndrea Bittau const __be32 var32 = htonl(elapsed_time); 4211bc09869SIan McDonald memcpy(to, &var32, 4); 4221bc09869SIan McDonald } 4237c657876SArnaldo Carvalho de Melo 4242d0817d1SArnaldo Carvalho de Melo return 0; 4257c657876SArnaldo Carvalho de Melo } 4267c657876SArnaldo Carvalho de Melo 427d3710566SGerrit Renker /** 428d3710566SGerrit Renker * dccp_insert_option_mandatory - Mandatory option (5.8.2) 429d3710566SGerrit Renker * Note that since we are using skb_push, this function needs to be called 430d3710566SGerrit Renker * _after_ inserting the option it is supposed to influence (stack order). 431d3710566SGerrit Renker */ 432d3710566SGerrit Renker int dccp_insert_option_mandatory(struct sk_buff *skb) 433d3710566SGerrit Renker { 434d3710566SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN) 435d3710566SGerrit Renker return -1; 436d3710566SGerrit Renker 437d3710566SGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len++; 438d3710566SGerrit Renker *skb_push(skb, 1) = DCCPO_MANDATORY; 439d3710566SGerrit Renker return 0; 440d3710566SGerrit Renker } 441d3710566SGerrit Renker 4428c862c23SGerrit Renker /** 4438c862c23SGerrit Renker * dccp_insert_fn_opt - Insert single Feature-Negotiation option into @skb 4448c862c23SGerrit Renker * @type: %DCCPO_CHANGE_L, %DCCPO_CHANGE_R, %DCCPO_CONFIRM_L, %DCCPO_CONFIRM_R 4458c862c23SGerrit Renker * @feat: one out of %dccp_feature_numbers 4468c862c23SGerrit Renker * @val: NN value or SP array (preferred element first) to copy 4478c862c23SGerrit Renker * @len: true length of @val in bytes (excluding first element repetition) 4488c862c23SGerrit Renker * @repeat_first: whether to copy the first element of @val twice 4498c862c23SGerrit Renker * The last argument is used to construct Confirm options, where the preferred 4508c862c23SGerrit Renker * value and the preference list appear separately (RFC 4340, 6.3.1). Preference 4518c862c23SGerrit Renker * lists are kept such that the preferred entry is always first, so we only need 4528c862c23SGerrit Renker * to copy twice, and avoid the overhead of cloning into a bigger array. 4538c862c23SGerrit Renker */ 4548c862c23SGerrit Renker int dccp_insert_fn_opt(struct sk_buff *skb, u8 type, u8 feat, 4558c862c23SGerrit Renker u8 *val, u8 len, bool repeat_first) 4564829007cSGerrit Renker { 4578c862c23SGerrit Renker u8 tot_len, *to; 4584829007cSGerrit Renker 4598c862c23SGerrit Renker /* take the `Feature' field and possible repetition into account */ 4608c862c23SGerrit Renker if (len > (DCCP_SINGLE_OPT_MAXLEN - 2)) { 4618c862c23SGerrit Renker DCCP_WARN("length %u for feature %u too large\n", len, feat); 462cf9ddf73SGerrit Renker return -1; 463cf9ddf73SGerrit Renker } 464cf9ddf73SGerrit Renker 4658c862c23SGerrit Renker if (unlikely(val == NULL || len == 0)) 4668c862c23SGerrit Renker len = repeat_first = 0; 4678c862c23SGerrit Renker tot_len = 3 + repeat_first + len; 468410e27a4SGerrit Renker 4698c862c23SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_opt_len + tot_len > DCCP_MAX_OPT_LEN) { 4708c862c23SGerrit Renker DCCP_WARN("packet too small for feature %d option!\n", feat); 4718c862c23SGerrit Renker return -1; 4728c862c23SGerrit Renker } 4738c862c23SGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len += tot_len; 4748c862c23SGerrit Renker 4758c862c23SGerrit Renker to = skb_push(skb, tot_len); 476afe00251SAndrea Bittau *to++ = type; 4778c862c23SGerrit Renker *to++ = tot_len; 478afe00251SAndrea Bittau *to++ = feat; 479afe00251SAndrea Bittau 4808c862c23SGerrit Renker if (repeat_first) 4818c862c23SGerrit Renker *to++ = *val; 482afe00251SAndrea Bittau if (len) 483afe00251SAndrea Bittau memcpy(to, val, len); 484410e27a4SGerrit Renker return 0; 485410e27a4SGerrit Renker } 486410e27a4SGerrit Renker 487af3b867eSGerrit Renker /* The length of all options needs to be a multiple of 4 (5.8) */ 488af3b867eSGerrit Renker static void dccp_insert_option_padding(struct sk_buff *skb) 489af3b867eSGerrit Renker { 490af3b867eSGerrit Renker int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; 491af3b867eSGerrit Renker 492af3b867eSGerrit Renker if (padding != 0) { 493af3b867eSGerrit Renker padding = 4 - padding; 494af3b867eSGerrit Renker memset(skb_push(skb, padding), 0, padding); 495af3b867eSGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len += padding; 496af3b867eSGerrit Renker } 497af3b867eSGerrit Renker } 498af3b867eSGerrit Renker 4992d0817d1SArnaldo Carvalho de Melo int dccp_insert_options(struct sock *sk, struct sk_buff *skb) 5007c657876SArnaldo Carvalho de Melo { 5017c657876SArnaldo Carvalho de Melo struct dccp_sock *dp = dccp_sk(sk); 5027c657876SArnaldo Carvalho de Melo 5037c657876SArnaldo Carvalho de Melo DCCP_SKB_CB(skb)->dccpd_opt_len = 0; 5047c657876SArnaldo Carvalho de Melo 5054098dce5SGerrit Renker if (dp->dccps_send_ndp_count && dccp_insert_option_ndp(sk, skb)) 5062d0817d1SArnaldo Carvalho de Melo return -1; 5077c657876SArnaldo Carvalho de Melo 5088b7b6c75SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) { 5098b7b6c75SGerrit Renker 5108b7b6c75SGerrit Renker /* Feature Negotiation */ 5118b7b6c75SGerrit Renker if (dccp_feat_insert_opts(dp, NULL, skb)) 5122d0817d1SArnaldo Carvalho de Melo return -1; 5138b7b6c75SGerrit Renker 5148b7b6c75SGerrit Renker if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) { 5158b7b6c75SGerrit Renker /* 5168b7b6c75SGerrit Renker * Obtain RTT sample from Request/Response exchange. 51759b80802SGerrit Renker * This is currently used for TFRC initialisation. 5188b7b6c75SGerrit Renker */ 519a7d13fbfSGerrit Renker if (dccp_insert_option_timestamp(skb)) 5208b7b6c75SGerrit Renker return -1; 5218b7b6c75SGerrit Renker 5226fdd34d4SGerrit Renker } else if (dp->dccps_hc_rx_ackvec != NULL && 5238b7b6c75SGerrit Renker dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) && 5248b7b6c75SGerrit Renker dccp_insert_option_ackvec(sk, skb)) { 5258b7b6c75SGerrit Renker return -1; 5268b7b6c75SGerrit Renker } 5277c657876SArnaldo Carvalho de Melo } 5287c657876SArnaldo Carvalho de Melo 529507d37cfSArnaldo Carvalho de Melo if (dp->dccps_hc_rx_insert_options) { 5302d0817d1SArnaldo Carvalho de Melo if (ccid_hc_rx_insert_options(dp->dccps_hc_rx_ccid, sk, skb)) 5312d0817d1SArnaldo Carvalho de Melo return -1; 532507d37cfSArnaldo Carvalho de Melo dp->dccps_hc_rx_insert_options = 0; 533507d37cfSArnaldo Carvalho de Melo } 5347c657876SArnaldo Carvalho de Melo 535b4d4f7c7SGerrit Renker if (dp->dccps_timestamp_echo != 0 && 536b4d4f7c7SGerrit Renker dccp_insert_option_timestamp_echo(dp, NULL, skb)) 537b4d4f7c7SGerrit Renker return -1; 538b4d4f7c7SGerrit Renker 539af3b867eSGerrit Renker dccp_insert_option_padding(skb); 540af3b867eSGerrit Renker return 0; 5417c657876SArnaldo Carvalho de Melo } 5422d0817d1SArnaldo Carvalho de Melo 543af3b867eSGerrit Renker int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) 544af3b867eSGerrit Renker { 545af3b867eSGerrit Renker DCCP_SKB_CB(skb)->dccpd_opt_len = 0; 546af3b867eSGerrit Renker 5478b7b6c75SGerrit Renker if (dccp_feat_insert_opts(NULL, dreq, skb)) 5488b7b6c75SGerrit Renker return -1; 5498b7b6c75SGerrit Renker 55059b80802SGerrit Renker /* Obtain RTT sample from Response/Ack exchange (used by TFRC). */ 55159b80802SGerrit Renker if (dccp_insert_option_timestamp(skb)) 55259b80802SGerrit Renker return -1; 55359b80802SGerrit Renker 554af3b867eSGerrit Renker if (dreq->dreq_timestamp_echo != 0 && 555af3b867eSGerrit Renker dccp_insert_option_timestamp_echo(NULL, dreq, skb)) 556af3b867eSGerrit Renker return -1; 557af3b867eSGerrit Renker 558af3b867eSGerrit Renker dccp_insert_option_padding(skb); 5592d0817d1SArnaldo Carvalho de Melo return 0; 5607c657876SArnaldo Carvalho de Melo } 561