diff options
Diffstat (limited to 'net/dccp/options.c')
-rw-r--r-- | net/dccp/options.c | 139 |
1 files changed, 91 insertions, 48 deletions
diff --git a/net/dccp/options.c b/net/dccp/options.c index d286cff..d2a84a2 100644 --- a/net/dccp/options.c +++ b/net/dccp/options.c @@ -46,7 +46,13 @@ static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len) return value; } -int dccp_parse_options(struct sock *sk, struct sk_buff *skb) +/** + * dccp_parse_options - Parse DCCP options present in @skb + * @sk: client|server|listening dccp socket (when @dreq != NULL) + * @dreq: request socket to use during connection setup, or NULL + */ +int dccp_parse_options(struct sock *sk, struct dccp_request_sock *dreq, + struct sk_buff *skb) { struct dccp_sock *dp = dccp_sk(sk); const struct dccp_hdr *dh = dccp_hdr(skb); @@ -92,6 +98,20 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) goto out_invalid_option; } + /* + * CCID-Specific Options (from RFC 4340, sec. 10.3): + * + * Option numbers 128 through 191 are for options sent from the + * HC-Sender to the HC-Receiver; option numbers 192 through 255 + * are for options sent from the HC-Receiver to the HC-Sender. + * + * CCID-specific options are ignored during connection setup, as + * negotiation may still be in progress (see RFC 4340, 10.3). + * + */ + if (dreq != NULL && opt >= 128) + goto ignore_option; + switch (opt) { case DCCPO_PADDING: break; @@ -112,6 +132,8 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) case DCCPO_CHANGE_L: /* fall through */ case DCCPO_CHANGE_R: + if (pkt_type == DCCP_PKT_DATA) + break; if (len < 2) goto out_invalid_option; rc = dccp_feat_change_recv(sk, opt, *value, value + 1, @@ -128,7 +150,9 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) case DCCPO_CONFIRM_L: /* fall through */ case DCCPO_CONFIRM_R: - if (len < 2) + if (pkt_type == DCCP_PKT_DATA) + break; + if (len < 2) /* FIXME this disallows empty confirm */ goto out_invalid_option; if (dccp_feat_confirm_recv(sk, opt, *value, value + 1, len - 1)) @@ -136,7 +160,7 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) break; case DCCPO_ACK_VECTOR_0: case DCCPO_ACK_VECTOR_1: - if (pkt_type == DCCP_PKT_DATA) + if (dccp_packet_without_ack(skb)) /* RFC 4340, 11.4 */ break; if (dccp_msk(sk)->dccpms_send_ack_vector && @@ -146,15 +170,27 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) case DCCPO_TIMESTAMP: if (len != 4) goto out_invalid_option; - + /* + * RFC 4340 13.1: "The precise time corresponding to + * Timestamp Value zero is not specified". We use + * zero to indicate absence of a meaningful timestamp. + */ opt_val = get_unaligned((__be32 *)value); - opt_recv->dccpor_timestamp = ntohl(opt_val); - - dp->dccps_timestamp_echo = opt_recv->dccpor_timestamp; - dp->dccps_timestamp_time = ktime_get_real(); + if (unlikely(opt_val == 0)) { + DCCP_WARN("Timestamp with zero value\n"); + break; + } + if (dreq != NULL) { + dreq->dreq_timestamp_echo = ntohl(opt_val); + dreq->dreq_timestamp_time = dccp_timestamp(); + } else { + opt_recv->dccpor_timestamp = + dp->dccps_timestamp_echo = ntohl(opt_val); + dp->dccps_timestamp_time = dccp_timestamp(); + } dccp_pr_debug("%s rx opt: TIMESTAMP=%u, ackno=%llu\n", - dccp_role(sk), opt_recv->dccpor_timestamp, + dccp_role(sk), ntohl(opt_val), (unsigned long long) DCCP_SKB_CB(skb)->dccpd_ack_seq); break; @@ -194,18 +230,17 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) opt_recv->dccpor_elapsed_time = elapsed_time; break; case DCCPO_ELAPSED_TIME: - if (len != 2 && len != 4) - goto out_invalid_option; - - if (pkt_type == DCCP_PKT_DATA) - continue; + if (dccp_packet_without_ack(skb)) /* RFC 4340, 13.2 */ + break; if (len == 2) { __be16 opt_val2 = get_unaligned((__be16 *)value); elapsed_time = ntohs(opt_val2); - } else { + } else if (len == 4) { opt_val = get_unaligned((__be32 *)value); elapsed_time = ntohl(opt_val); + } else { + goto out_invalid_option; } if (elapsed_time > opt_recv->dccpor_elapsed_time) @@ -214,15 +249,6 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) dccp_pr_debug("%s rx opt: ELAPSED_TIME=%d\n", dccp_role(sk), elapsed_time); break; - /* - * From RFC 4340, sec. 10.3: - * - * Option numbers 128 through 191 are for - * options sent from the HC-Sender to the - * HC-Receiver; option numbers 192 through 255 - * are for options sent from the HC-Receiver to - * the HC-Sender. - */ case 128 ... 191: { const u16 idx = value - options; @@ -246,7 +272,7 @@ int dccp_parse_options(struct sock *sk, struct sk_buff *skb) "implemented, ignoring", sk, opt, len); break; } - +ignore_option: if (opt != DCCPO_MANDATORY) mandatory = 0; } @@ -382,16 +408,24 @@ int dccp_insert_option_timestamp(struct sock *sk, struct sk_buff *skb) EXPORT_SYMBOL_GPL(dccp_insert_option_timestamp); -static int dccp_insert_option_timestamp_echo(struct sock *sk, +static int dccp_insert_option_timestamp_echo(struct dccp_sock *dp, + struct dccp_request_sock *dreq, struct sk_buff *skb) { - struct dccp_sock *dp = dccp_sk(sk); __be32 tstamp_echo; - int len, elapsed_time_len; unsigned char *to; - const suseconds_t delta = ktime_us_delta(ktime_get_real(), - dp->dccps_timestamp_time); - u32 elapsed_time = delta / 10; + u32 elapsed_time, elapsed_time_len, len; + + if (dreq != NULL) { + elapsed_time = dccp_timestamp() - dreq->dreq_timestamp_time; + tstamp_echo = htonl(dreq->dreq_timestamp_echo); + dreq->dreq_timestamp_echo = 0; + } else { + elapsed_time = dccp_timestamp() - dp->dccps_timestamp_time; + tstamp_echo = htonl(dp->dccps_timestamp_echo); + dp->dccps_timestamp_echo = 0; + } + elapsed_time_len = dccp_elapsed_time_len(elapsed_time); len = 6 + elapsed_time_len; @@ -404,7 +438,6 @@ static int dccp_insert_option_timestamp_echo(struct sock *sk, *to++ = DCCPO_TIMESTAMP_ECHO; *to++ = len; - tstamp_echo = htonl(dp->dccps_timestamp_echo); memcpy(to, &tstamp_echo, 4); to += 4; @@ -416,8 +449,6 @@ static int dccp_insert_option_timestamp_echo(struct sock *sk, memcpy(to, &var32, 4); } - dp->dccps_timestamp_echo = 0; - dp->dccps_timestamp_time = ktime_set(0, 0); return 0; } @@ -510,6 +541,18 @@ static int dccp_insert_options_feat(struct sock *sk, struct sk_buff *skb) return 0; } +/* The length of all options needs to be a multiple of 4 (5.8) */ +static void dccp_insert_option_padding(struct sk_buff *skb) +{ + int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; + + if (padding != 0) { + padding = 4 - padding; + memset(skb_push(skb, padding), 0, padding); + DCCP_SKB_CB(skb)->dccpd_opt_len += padding; + } +} + int dccp_insert_options(struct sock *sk, struct sk_buff *skb) { struct dccp_sock *dp = dccp_sk(sk); @@ -526,10 +569,6 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb) dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) && dccp_insert_option_ackvec(sk, skb)) return -1; - - if (dp->dccps_timestamp_echo != 0 && - dccp_insert_option_timestamp_echo(sk, skb)) - return -1; } if (dp->dccps_hc_rx_insert_options) { @@ -553,18 +592,22 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb) dccp_insert_option_timestamp(sk, skb)) return -1; - /* XXX: insert other options when appropriate */ + if (dp->dccps_timestamp_echo != 0 && + dccp_insert_option_timestamp_echo(dp, NULL, skb)) + return -1; + + dccp_insert_option_padding(skb); + return 0; +} - if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) { - /* The length of all options has to be a multiple of 4 */ - int padding = DCCP_SKB_CB(skb)->dccpd_opt_len % 4; +int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb) +{ + DCCP_SKB_CB(skb)->dccpd_opt_len = 0; - if (padding != 0) { - padding = 4 - padding; - memset(skb_push(skb, padding), 0, padding); - DCCP_SKB_CB(skb)->dccpd_opt_len += padding; - } - } + if (dreq->dreq_timestamp_echo != 0 && + dccp_insert_option_timestamp_echo(NULL, dreq, skb)) + return -1; + dccp_insert_option_padding(skb); return 0; } |