1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 3 #ifndef _LINUX_RSTREASON_H 4 #define _LINUX_RSTREASON_H 5 #include <net/dropreason-core.h> 6 #include <uapi/linux/mptcp.h> 7 8 #define DEFINE_RST_REASON(FN, FNe) \ 9 FN(NOT_SPECIFIED) \ 10 FN(NO_SOCKET) \ 11 FN(TCP_INVALID_ACK_SEQUENCE) \ 12 FN(TCP_RFC7323_PAWS) \ 13 FN(TCP_TOO_OLD_ACK) \ 14 FN(TCP_ACK_UNSENT_DATA) \ 15 FN(TCP_FLAGS) \ 16 FN(TCP_OLD_ACK) \ 17 FN(TCP_ABORT_ON_DATA) \ 18 FN(TCP_TIMEWAIT_SOCKET) \ 19 FN(INVALID_SYN) \ 20 FN(TCP_ABORT_ON_CLOSE) \ 21 FN(TCP_ABORT_ON_LINGER) \ 22 FN(TCP_ABORT_ON_MEMORY) \ 23 FN(TCP_STATE) \ 24 FN(TCP_KEEPALIVE_TIMEOUT) \ 25 FN(TCP_DISCONNECT_WITH_DATA) \ 26 FN(MPTCP_RST_EUNSPEC) \ 27 FN(MPTCP_RST_EMPTCP) \ 28 FN(MPTCP_RST_ERESOURCE) \ 29 FN(MPTCP_RST_EPROHIBIT) \ 30 FN(MPTCP_RST_EWQ2BIG) \ 31 FN(MPTCP_RST_EBADPERF) \ 32 FN(MPTCP_RST_EMIDDLEBOX) \ 33 FN(ERROR) \ 34 FNe(MAX) 35 36 /** 37 * enum sk_rst_reason - the reasons of socket reset 38 * 39 * The reasons of sk reset, which are used in DCCP/TCP/MPTCP protocols. 40 * 41 * There are three parts in order: 42 * 1) skb drop reasons: relying on drop reasons for such as passive reset 43 * 2) independent reset reasons: such as active reset reasons 44 * 3) reset reasons in MPTCP: only for MPTCP use 45 */ 46 enum sk_rst_reason { 47 /* Refer to include/net/dropreason-core.h 48 * Rely on skb drop reasons because it indicates exactly why RST 49 * could happen. 50 */ 51 /** @SK_RST_REASON_NOT_SPECIFIED: reset reason is not specified */ 52 SK_RST_REASON_NOT_SPECIFIED, 53 /** @SK_RST_REASON_NO_SOCKET: no valid socket that can be used */ 54 SK_RST_REASON_NO_SOCKET, 55 /** 56 * @SK_RST_REASON_TCP_INVALID_ACK_SEQUENCE: Not acceptable ACK SEQ 57 * field because ack sequence is not in the window between snd_una 58 * and snd_nxt 59 */ 60 SK_RST_REASON_TCP_INVALID_ACK_SEQUENCE, 61 /** 62 * @SK_RST_REASON_TCP_RFC7323_PAWS: PAWS check, corresponding to 63 * LINUX_MIB_PAWSESTABREJECTED, LINUX_MIB_PAWSACTIVEREJECTED 64 */ 65 SK_RST_REASON_TCP_RFC7323_PAWS, 66 /** @SK_RST_REASON_TCP_TOO_OLD_ACK: TCP ACK is too old */ 67 SK_RST_REASON_TCP_TOO_OLD_ACK, 68 /** 69 * @SK_RST_REASON_TCP_ACK_UNSENT_DATA: TCP ACK for data we haven't 70 * sent yet 71 */ 72 SK_RST_REASON_TCP_ACK_UNSENT_DATA, 73 /** @SK_RST_REASON_TCP_FLAGS: TCP flags invalid */ 74 SK_RST_REASON_TCP_FLAGS, 75 /** @SK_RST_REASON_TCP_OLD_ACK: TCP ACK is old, but in window */ 76 SK_RST_REASON_TCP_OLD_ACK, 77 /** 78 * @SK_RST_REASON_TCP_ABORT_ON_DATA: abort on data 79 * corresponding to LINUX_MIB_TCPABORTONDATA 80 */ 81 SK_RST_REASON_TCP_ABORT_ON_DATA, 82 83 /* Here start with the independent reasons */ 84 /** @SK_RST_REASON_TCP_TIMEWAIT_SOCKET: happen on the timewait socket */ 85 SK_RST_REASON_TCP_TIMEWAIT_SOCKET, 86 /** 87 * @SK_RST_REASON_INVALID_SYN: receive bad syn packet 88 * RFC 793 says if the state is not CLOSED/LISTEN/SYN-SENT then 89 * "fourth, check the SYN bit,...If the SYN is in the window it is 90 * an error, send a reset" 91 */ 92 SK_RST_REASON_INVALID_SYN, 93 /** 94 * @SK_RST_REASON_TCP_ABORT_ON_CLOSE: abort on close 95 * corresponding to LINUX_MIB_TCPABORTONCLOSE 96 */ 97 SK_RST_REASON_TCP_ABORT_ON_CLOSE, 98 /** 99 * @SK_RST_REASON_TCP_ABORT_ON_LINGER: abort on linger 100 * corresponding to LINUX_MIB_TCPABORTONLINGER 101 */ 102 SK_RST_REASON_TCP_ABORT_ON_LINGER, 103 /** 104 * @SK_RST_REASON_TCP_ABORT_ON_MEMORY: abort on memory 105 * corresponding to LINUX_MIB_TCPABORTONMEMORY 106 */ 107 SK_RST_REASON_TCP_ABORT_ON_MEMORY, 108 /** 109 * @SK_RST_REASON_TCP_STATE: abort on tcp state 110 * Please see RFC 9293 for all possible reset conditions 111 */ 112 SK_RST_REASON_TCP_STATE, 113 /** 114 * @SK_RST_REASON_TCP_KEEPALIVE_TIMEOUT: time to timeout 115 * When we have already run out of all the chances, which means 116 * keepalive timeout, we have to reset the connection 117 */ 118 SK_RST_REASON_TCP_KEEPALIVE_TIMEOUT, 119 /** 120 * @SK_RST_REASON_TCP_DISCONNECT_WITH_DATA: disconnect when write 121 * queue is not empty 122 * It means user has written data into the write queue when doing 123 * disconnecting, so we have to send an RST. 124 */ 125 SK_RST_REASON_TCP_DISCONNECT_WITH_DATA, 126 127 /* Copy from include/uapi/linux/mptcp.h. 128 * These reset fields will not be changed since they adhere to 129 * RFC 8684. So do not touch them. I'm going to list each definition 130 * of them respectively. 131 */ 132 /** 133 * @SK_RST_REASON_MPTCP_RST_EUNSPEC: Unspecified error. 134 * This is the default error; it implies that the subflow is no 135 * longer available. The presence of this option shows that the 136 * RST was generated by an MPTCP-aware device. 137 */ 138 SK_RST_REASON_MPTCP_RST_EUNSPEC, 139 /** 140 * @SK_RST_REASON_MPTCP_RST_EMPTCP: MPTCP-specific error. 141 * An error has been detected in the processing of MPTCP options. 142 * This is the usual reason code to return in the cases where a RST 143 * is being sent to close a subflow because of an invalid response. 144 */ 145 SK_RST_REASON_MPTCP_RST_EMPTCP, 146 /** 147 * @SK_RST_REASON_MPTCP_RST_ERESOURCE: Lack of resources. 148 * This code indicates that the sending host does not have enough 149 * resources to support the terminated subflow. 150 */ 151 SK_RST_REASON_MPTCP_RST_ERESOURCE, 152 /** 153 * @SK_RST_REASON_MPTCP_RST_EPROHIBIT: Administratively prohibited. 154 * This code indicates that the requested subflow is prohibited by 155 * the policies of the sending host. 156 */ 157 SK_RST_REASON_MPTCP_RST_EPROHIBIT, 158 /** 159 * @SK_RST_REASON_MPTCP_RST_EWQ2BIG: Too much outstanding data. 160 * This code indicates that there is an excessive amount of data 161 * that needs to be transmitted over the terminated subflow while 162 * having already been acknowledged over one or more other subflows. 163 * This may occur if a path has been unavailable for a short period 164 * and it is more efficient to reset and start again than it is to 165 * retransmit the queued data. 166 */ 167 SK_RST_REASON_MPTCP_RST_EWQ2BIG, 168 /** 169 * @SK_RST_REASON_MPTCP_RST_EBADPERF: Unacceptable performance. 170 * This code indicates that the performance of this subflow was 171 * too low compared to the other subflows of this Multipath TCP 172 * connection. 173 */ 174 SK_RST_REASON_MPTCP_RST_EBADPERF, 175 /** 176 * @SK_RST_REASON_MPTCP_RST_EMIDDLEBOX: Middlebox interference. 177 * Middlebox interference has been detected over this subflow, 178 * making MPTCP signaling invalid. For example, this may be sent 179 * if the checksum does not validate. 180 */ 181 SK_RST_REASON_MPTCP_RST_EMIDDLEBOX, 182 183 /** @SK_RST_REASON_ERROR: unexpected error happens */ 184 SK_RST_REASON_ERROR, 185 186 /** 187 * @SK_RST_REASON_MAX: Maximum of socket reset reasons. 188 * It shouldn't be used as a real 'reason'. 189 */ 190 SK_RST_REASON_MAX, 191 }; 192 193 /* Convert skb drop reasons to enum sk_rst_reason type */ 194 static inline enum sk_rst_reason sk_rst_convert_drop_reason(enum skb_drop_reason reason)195 sk_rst_convert_drop_reason(enum skb_drop_reason reason) 196 { 197 switch (reason) { 198 case SKB_DROP_REASON_NOT_SPECIFIED: 199 return SK_RST_REASON_NOT_SPECIFIED; 200 case SKB_DROP_REASON_NO_SOCKET: 201 return SK_RST_REASON_NO_SOCKET; 202 case SKB_DROP_REASON_TCP_INVALID_ACK_SEQUENCE: 203 return SK_RST_REASON_TCP_INVALID_ACK_SEQUENCE; 204 case SKB_DROP_REASON_TCP_RFC7323_PAWS: 205 return SK_RST_REASON_TCP_RFC7323_PAWS; 206 case SKB_DROP_REASON_TCP_TOO_OLD_ACK: 207 return SK_RST_REASON_TCP_TOO_OLD_ACK; 208 case SKB_DROP_REASON_TCP_ACK_UNSENT_DATA: 209 return SK_RST_REASON_TCP_ACK_UNSENT_DATA; 210 case SKB_DROP_REASON_TCP_FLAGS: 211 return SK_RST_REASON_TCP_FLAGS; 212 case SKB_DROP_REASON_TCP_OLD_ACK: 213 return SK_RST_REASON_TCP_OLD_ACK; 214 case SKB_DROP_REASON_TCP_ABORT_ON_DATA: 215 return SK_RST_REASON_TCP_ABORT_ON_DATA; 216 default: 217 /* If we don't have our own corresponding reason */ 218 return SK_RST_REASON_NOT_SPECIFIED; 219 } 220 } 221 #endif 222