1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 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 * $FreeBSD$ 31 */ 32 33 /* 34 * Debugnet provides a reliable, bidirectional, UDP-encapsulated datagram 35 * transport while a machine is in a debug state. (N-1 CPUs stopped, 36 * interrupts disabled, may or may not be in a panic(9) state.) Only one 37 * stream may be active at a time. A dedicated server must be running to 38 * accept connections. 39 */ 40 41 #pragma once 42 43 #include <sys/types.h> 44 #include <netinet/in.h> 45 46 /* 47 * Debugnet protocol details. 48 */ 49 #define DEBUGNET_HERALD 1 /* Connection handshake. */ 50 #define DEBUGNET_FINISHED 2 /* Close the connection. */ 51 #define DEBUGNET_DATA 3 /* Contains data. */ 52 53 struct debugnet_msg_hdr { 54 uint32_t mh_type; /* Debugnet message type. */ 55 uint32_t mh_seqno; /* Match acks with msgs. */ 56 uint64_t mh_offset; /* Offset in fragment. */ 57 uint32_t mh_len; /* Attached data (bytes). */ 58 uint32_t mh_aux2; /* Consumer-specific. */ 59 } __packed; 60 61 struct debugnet_ack { 62 uint32_t da_seqno; /* Match acks with msgs. */ 63 } __packed; 64 65 #define DEBUGNET_MAX_IN_FLIGHT 64 66 67 #ifdef _KERNEL 68 /* 69 * Hook API for network drivers. 70 */ 71 enum debugnet_ev { 72 DEBUGNET_START, 73 DEBUGNET_END, 74 }; 75 76 struct ifnet; 77 struct mbuf; 78 typedef void debugnet_init_t(struct ifnet *, int *nrxr, int *ncl, int *clsize); 79 typedef void debugnet_event_t(struct ifnet *, enum debugnet_ev); 80 typedef int debugnet_transmit_t(struct ifnet *, struct mbuf *); 81 typedef int debugnet_poll_t(struct ifnet *, int); 82 83 struct debugnet_methods { 84 debugnet_init_t *dn_init; 85 debugnet_event_t *dn_event; 86 debugnet_transmit_t *dn_transmit; 87 debugnet_poll_t *dn_poll; 88 }; 89 90 #define DEBUGNET_SUPPORTED_NIC(ifp) \ 91 ((ifp)->if_debugnet_methods != NULL && (ifp)->if_type == IFT_ETHER) 92 93 struct debugnet_pcb; /* opaque */ 94 95 /* 96 * Debugnet consumer API. 97 */ 98 struct debugnet_conn_params { 99 struct ifnet *dc_ifp; 100 in_addr_t dc_client; 101 in_addr_t dc_server; 102 in_addr_t dc_gateway; 103 104 uint16_t dc_herald_port; 105 uint16_t dc_client_port; 106 107 const void *dc_herald_data; 108 uint32_t dc_herald_datalen; 109 110 /* 111 * If NULL, debugnet is a unidirectional channel from panic machine to 112 * remote server (like netdump). 113 * 114 * If handler is non-NULL, packets received on the client port that are 115 * not just tx acks are forwarded to the provided handler. 116 * 117 * The mbuf chain will have all non-debugnet framing headers removed 118 * (ethernet, inet, udp). It will start with a debugnet_msg_hdr, of 119 * which the header is guaranteed to be contiguous. If m_pullup is 120 * used, the supplied in-out mbuf pointer should be updated 121 * appropriately. 122 * 123 * If the handler frees the mbuf chain, it should set the mbuf pointer 124 * to NULL. Otherwise, the debugnet input framework will free the 125 * chain. 126 */ 127 void (*dc_rx_handler)(struct debugnet_pcb *, struct mbuf **); 128 }; 129 130 /* 131 * Open a unidirectional stream to the specified server's herald port. 132 * 133 * If all goes well, the server will send ACK from a different port to our ack 134 * port. This allows servers to somewhat gracefully handle multiple debugnet 135 * clients. (Clients are limited to single connections.) 136 * 137 * Returns zero on success, or errno. 138 */ 139 int debugnet_connect(const struct debugnet_conn_params *, 140 struct debugnet_pcb **pcb_out); 141 142 /* 143 * Free a debugnet stream that was previously successfully opened. 144 * 145 * No attempt is made to cleanly terminate communication with the remote 146 * server. Consumers should first send an empty DEBUGNET_FINISHED message, or 147 * otherwise let the remote know they are signing off. 148 */ 149 void debugnet_free(struct debugnet_pcb *); 150 151 /* 152 * Send a message, with common debugnet_msg_hdr header, to the connected remote 153 * server. 154 * 155 * - mhtype translates directly to mh_type (e.g., DEBUGNET_DATA, or some other 156 * protocol-specific type). 157 * - Data and datalen describe the attached data; datalen may be zero. 158 * - If auxdata is NULL, mh_offset's initial value and mh_aux2 will be zero. 159 * Otherwise, mh_offset's initial value will be auxdata->dp_offset_start and 160 * mh_aux2 will have the value of auxdata->dp_aux2. 161 * 162 * Returns zero on success, or an errno on failure. 163 */ 164 struct debugnet_proto_aux { 165 uint64_t dp_offset_start; 166 uint32_t dp_aux2; 167 }; 168 int debugnet_send(struct debugnet_pcb *, uint32_t mhtype, const void *data, 169 uint32_t datalen, const struct debugnet_proto_aux *auxdata); 170 171 /* 172 * A simple wrapper around the above when no data or auxdata is needed. 173 */ 174 static inline int 175 debugnet_sendempty(struct debugnet_pcb *pcb, uint32_t mhtype) 176 { 177 return (debugnet_send(pcb, mhtype, NULL, 0, NULL)); 178 } 179 180 /* 181 * PCB accessors. 182 */ 183 184 /* 185 * Get the 48-bit MAC address of the discovered next hop (gateway, or 186 * destination server if it is on the same segment. 187 */ 188 const unsigned char *debugnet_get_gw_mac(const struct debugnet_pcb *); 189 190 /* 191 * Callbacks from core mbuf code. 192 */ 193 void debugnet_any_ifnet_update(struct ifnet *); 194 195 /* 196 * DDB parsing helper for common debugnet options. 197 * 198 * -s <server> [-g <gateway -c <localip> -i <interface>] 199 * 200 * Order is not significant. Interface is an online interface that supports 201 * debugnet and can route to the debugnet server. The other parameters are all 202 * IP addresses. Only the server parameter is required. The others are 203 * inferred automatically from the routing table, if not explicitly provided. 204 * 205 * Provides basic '-h' using provided 'cmd' string. 206 * 207 * Returns zero on success, or errno. 208 */ 209 struct debugnet_ddb_config { 210 struct ifnet *dd_ifp; /* not ref'd */ 211 in_addr_t dd_client; 212 in_addr_t dd_server; 213 in_addr_t dd_gateway; 214 bool dd_has_client : 1; 215 bool dd_has_gateway : 1; 216 }; 217 int debugnet_parse_ddb_cmd(const char *cmd, 218 struct debugnet_ddb_config *result); 219 220 /* Expose sysctl variables for netdump(4) to alias. */ 221 extern int debugnet_npolls; 222 extern int debugnet_nretries; 223 extern int debugnet_arp_nretries; 224 225 /* 226 * Conditionally-defined macros for device drivers so we can avoid ifdef 227 * wrappers in every single implementation. 228 */ 229 #ifdef DEBUGNET 230 #define DEBUGNET_DEFINE(driver) \ 231 static debugnet_init_t driver##_debugnet_init; \ 232 static debugnet_event_t driver##_debugnet_event; \ 233 static debugnet_transmit_t driver##_debugnet_transmit; \ 234 static debugnet_poll_t driver##_debugnet_poll; \ 235 \ 236 static struct debugnet_methods driver##_debugnet_methods = { \ 237 .dn_init = driver##_debugnet_init, \ 238 .dn_event = driver##_debugnet_event, \ 239 .dn_transmit = driver##_debugnet_transmit, \ 240 .dn_poll = driver##_debugnet_poll, \ 241 } 242 243 #define DEBUGNET_NOTIFY_MTU(ifp) debugnet_any_ifnet_update(ifp) 244 245 #define DEBUGNET_SET(ifp, driver) \ 246 (ifp)->if_debugnet_methods = &driver##_debugnet_methods 247 248 #else /* !DEBUGNET || !INET */ 249 250 #define DEBUGNET_DEFINE(driver) 251 #define DEBUGNET_NOTIFY_MTU(ifp) 252 #define DEBUGNET_SET(ifp, driver) 253 254 #endif /* DEBUGNET && INET */ 255 #endif /* _KERNEL */ 256