debugnet.h (9015B) - Raw
1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2019 Isilon Systems, LLC. 5 * Copyright (c) 2005-2014 Sandvine Incorporated 6 * Copyright (c) 2000 Darrell Anderson <anderson@cs.duke.edu> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 /* 32 * Debugnet provides a reliable, bidirectional, UDP-encapsulated datagram 33 * transport while a machine is in a debug state. (N-1 CPUs stopped, 34 * interrupts disabled, may or may not be in a panic(9) state.) Only one 35 * stream may be active at a time. A dedicated server must be running to 36 * accept connections. 37 */ 38 39 #pragma once 40 41 #include <sys/types.h> 42 #include <netinet/in.h> 43 44 /* 45 * Debugnet protocol details. 46 */ 47 #define DEBUGNET_HERALD 1 /* Connection handshake. */ 48 #define DEBUGNET_FINISHED 2 /* Close the connection. */ 49 #define DEBUGNET_DATA 3 /* Contains data. */ 50 51 struct debugnet_msg_hdr { 52 uint32_t mh_type; /* Debugnet message type. */ 53 uint32_t mh_seqno; /* Match acks with msgs. */ 54 uint64_t mh_offset; /* Offset in fragment. */ 55 uint32_t mh_len; /* Attached data (bytes). */ 56 uint32_t mh_aux2; /* Consumer-specific. */ 57 } __packed; 58 59 struct debugnet_ack { 60 uint32_t da_seqno; /* Match acks with msgs. */ 61 } __packed; 62 63 #define DEBUGNET_MAX_IN_FLIGHT 64 64 65 #ifdef _KERNEL 66 /* 67 * Hook API for network drivers. 68 */ 69 enum debugnet_ev { 70 DEBUGNET_START, 71 DEBUGNET_END, 72 }; 73 74 struct ifnet; 75 struct mbuf; 76 typedef void debugnet_init_t(struct ifnet *, int *nrxr, int *ncl, int *clsize); 77 typedef void debugnet_event_t(struct ifnet *, enum debugnet_ev); 78 typedef int debugnet_transmit_t(struct ifnet *, struct mbuf *); 79 typedef int debugnet_poll_t(struct ifnet *, int); 80 81 struct debugnet_methods { 82 debugnet_init_t *dn_init; 83 debugnet_event_t *dn_event; 84 debugnet_transmit_t *dn_transmit; 85 debugnet_poll_t *dn_poll; 86 }; 87 88 #define DEBUGNET_SUPPORTED_NIC(ifp) \ 89 ((ifp)->if_debugnet_methods != NULL && (ifp)->if_type == IFT_ETHER) 90 91 struct debugnet_pcb; /* opaque */ 92 93 /* 94 * Debugnet consumer API. 95 */ 96 struct debugnet_conn_params { 97 struct ifnet *dc_ifp; 98 in_addr_t dc_client; 99 in_addr_t dc_server; 100 in_addr_t dc_gateway; 101 102 uint16_t dc_herald_port; 103 uint16_t dc_client_port; 104 105 const void *dc_herald_data; 106 uint32_t dc_herald_datalen; 107 108 /* 109 * Consistent with debugnet_send(), aux parameters to debugnet 110 * functions are provided host-endian (but converted to 111 * network endian on the wire). 112 */ 113 uint32_t dc_herald_aux2; 114 uint64_t dc_herald_offset; 115 116 /* 117 * If NULL, debugnet is a unidirectional channel from panic machine to 118 * remote server (like netdump). 119 * 120 * If handler is non-NULL, packets received on the client port that are 121 * not just tx acks are forwarded to the provided handler. 122 * 123 * The mbuf chain will have all non-debugnet framing headers removed 124 * (ethernet, inet, udp). It will start with a debugnet_msg_hdr, of 125 * which the header is guaranteed to be contiguous. If m_pullup is 126 * used, the supplied in-out mbuf pointer should be updated 127 * appropriately. 128 * 129 * If the handler frees the mbuf chain, it should set the mbuf pointer 130 * to NULL. Otherwise, the debugnet input framework will free the 131 * chain. 132 * 133 * The handler should ACK receieved packets with debugnet_ack_output. 134 */ 135 int (*dc_rx_handler)(struct mbuf *); 136 137 /* Cleanup signal for bidirectional protocols. */ 138 void (*dc_finish_handler)(void); 139 }; 140 141 /* 142 * Open a stream to the specified server's herald port. 143 * 144 * If all goes well, the server will send ACK from a different port to our ack 145 * port. This allows servers to somewhat gracefully handle multiple debugnet 146 * clients. (Clients are limited to single connections.) 147 * 148 * Returns zero on success, or errno. 149 */ 150 int debugnet_connect(const struct debugnet_conn_params *, 151 struct debugnet_pcb **pcb_out); 152 153 /* 154 * Free a debugnet stream that was previously successfully opened. 155 * 156 * No attempt is made to cleanly terminate communication with the remote 157 * server. Consumers should first send an empty DEBUGNET_FINISHED message, or 158 * otherwise let the remote know they are signing off. 159 */ 160 void debugnet_free(struct debugnet_pcb *); 161 162 /* 163 * Send a message, with common debugnet_msg_hdr header, to the connected remote 164 * server. 165 * 166 * - mhtype translates directly to mh_type (e.g., DEBUGNET_DATA, or some other 167 * protocol-specific type). 168 * - Data and datalen describe the attached data; datalen may be zero. 169 * - If auxdata is NULL, mh_offset's initial value and mh_aux2 will be zero. 170 * Otherwise, mh_offset's initial value will be auxdata->dp_offset_start and 171 * mh_aux2 will have the value of auxdata->dp_aux2. 172 * 173 * Returns zero on success, or an errno on failure. 174 */ 175 struct debugnet_proto_aux { 176 uint64_t dp_offset_start; 177 uint32_t dp_aux2; 178 }; 179 int debugnet_send(struct debugnet_pcb *, uint32_t mhtype, const void *data, 180 uint32_t datalen, const struct debugnet_proto_aux *auxdata); 181 182 /* 183 * A simple wrapper around the above when no data or auxdata is needed. 184 */ 185 static inline int 186 debugnet_sendempty(struct debugnet_pcb *pcb, uint32_t mhtype) 187 { 188 return (debugnet_send(pcb, mhtype, NULL, 0, NULL)); 189 } 190 191 /* 192 * Full-duplex RX should ACK received messages. 193 */ 194 int debugnet_ack_output(struct debugnet_pcb *, uint32_t seqno /*net endian*/); 195 196 /* 197 * Check and/or wait for further packets. 198 */ 199 void debugnet_network_poll(struct debugnet_pcb *); 200 201 /* 202 * PCB accessors. 203 */ 204 205 /* 206 * Get the 48-bit MAC address of the discovered next hop (gateway, or 207 * destination server if it is on the same segment. 208 */ 209 const unsigned char *debugnet_get_gw_mac(const struct debugnet_pcb *); 210 211 /* 212 * Get the connected server address. 213 */ 214 const in_addr_t *debugnet_get_server_addr(const struct debugnet_pcb *); 215 216 /* 217 * Get the connected server port. 218 */ 219 const uint16_t debugnet_get_server_port(const struct debugnet_pcb *); 220 221 /* 222 * Callbacks from core mbuf code. 223 */ 224 void debugnet_any_ifnet_update(struct ifnet *); 225 226 /* 227 * DDB parsing helper for common debugnet options. 228 * 229 * -s <server> [-g <gateway -c <localip> -i <interface>] 230 * 231 * Order is not significant. Interface is an online interface that supports 232 * debugnet and can route to the debugnet server. The other parameters are all 233 * IP addresses. Only the server parameter is required. The others are 234 * inferred automatically from the routing table, if not explicitly provided. 235 * 236 * Provides basic '-h' using provided 'cmd' string. 237 * 238 * Returns zero on success, or errno. 239 */ 240 struct debugnet_ddb_config { 241 struct ifnet *dd_ifp; /* not ref'd */ 242 in_addr_t dd_client; 243 in_addr_t dd_server; 244 in_addr_t dd_gateway; 245 bool dd_has_client : 1; 246 bool dd_has_gateway : 1; 247 }; 248 int debugnet_parse_ddb_cmd(const char *cmd, 249 struct debugnet_ddb_config *result); 250 251 /* Expose sysctl variables for netdump(4) to alias. */ 252 extern int debugnet_npolls; 253 extern int debugnet_nretries; 254 extern int debugnet_arp_nretries; 255 256 /* 257 * Conditionally-defined macros for device drivers so we can avoid ifdef 258 * wrappers in every single implementation. 259 */ 260 #ifdef DEBUGNET 261 #define DEBUGNET_DEFINE(driver) \ 262 static debugnet_init_t driver##_debugnet_init; \ 263 static debugnet_event_t driver##_debugnet_event; \ 264 static debugnet_transmit_t driver##_debugnet_transmit; \ 265 static debugnet_poll_t driver##_debugnet_poll; \ 266 \ 267 static struct debugnet_methods driver##_debugnet_methods = { \ 268 .dn_init = driver##_debugnet_init, \ 269 .dn_event = driver##_debugnet_event, \ 270 .dn_transmit = driver##_debugnet_transmit, \ 271 .dn_poll = driver##_debugnet_poll, \ 272 } 273 274 #define DEBUGNET_NOTIFY_MTU(ifp) debugnet_any_ifnet_update(ifp) 275 276 #define DEBUGNET_SET(ifp, driver) \ 277 if_setdebugnet_methods((ifp), &driver##_debugnet_methods) 278 279 #else /* !DEBUGNET || !INET */ 280 281 #define DEBUGNET_DEFINE(driver) 282 #define DEBUGNET_NOTIFY_MTU(ifp) 283 #define DEBUGNET_SET(ifp, driver) 284 285 #endif /* DEBUGNET && INET */ 286 #endif /* _KERNEL */