1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2005 Paolo Pisati <piso@FreeBSD.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 /* 32 * Alias_mod.h defines the outside world interfaces for the packet aliasing 33 * modular framework 34 */ 35 36 #ifndef _ALIAS_MOD_H_ 37 #define _ALIAS_MOD_H_ 38 39 #ifdef _KERNEL 40 MALLOC_DECLARE(M_ALIAS); 41 42 /* Use kernel allocator. */ 43 #if defined(_SYS_MALLOC_H_) 44 #undef malloc 45 #define malloc(x) malloc(x, M_ALIAS, M_NOWAIT|M_ZERO) 46 #define calloc(n, x) mallocarray((n), (x), M_ALIAS, M_NOWAIT|M_ZERO) 47 #define free(x) free(x, M_ALIAS) 48 #endif 49 #endif 50 51 /* Packet flow direction flags. */ 52 #define IN 0x0001 53 #define OUT 0x0002 54 #define NODIR 0x4000 55 56 /* Working protocol flags. */ 57 #define IP 0x01 58 #define TCP 0x02 59 #define UDP 0x04 60 61 /* 62 * Data passed to protocol handler module, it must be filled 63 * right before calling find_handler() to determine which 64 * module is elegible to be called. 65 */ 66 struct alias_data { 67 struct alias_link *lnk; 68 struct in_addr *oaddr; /* Original address. */ 69 struct in_addr *aaddr; /* Alias address. */ 70 uint16_t *aport; /* Alias port. */ 71 uint16_t *sport, *dport; /* Source & destination port */ 72 uint16_t maxpktsize; /* Max packet size. */ 73 }; 74 75 /* 76 * This structure contains all the information necessary to make 77 * a protocol handler correctly work. 78 */ 79 struct proto_handler { 80 u_int pri; /* Handler priority. */ 81 int16_t dir; /* Flow direction. */ 82 uint8_t proto; /* Working protocol. */ 83 /* Fingerprint * function. */ 84 int (*fingerprint)(struct libalias *, struct alias_data *); 85 /* Aliasing * function. */ 86 int (*protohandler)(struct libalias *, struct ip *, 87 struct alias_data *); 88 TAILQ_ENTRY(proto_handler) link; 89 }; 90 91 /* End of handlers. */ 92 #define EOH .dir = NODIR 93 94 /* Functions used with protocol handlers. */ 95 int LibAliasAttachHandlers(struct proto_handler *); 96 int LibAliasDetachHandlers(struct proto_handler *); 97 int find_handler(int8_t, int8_t, struct libalias *, struct ip *, 98 struct alias_data *); 99 struct proto_handler *first_handler(void); 100 101 #ifndef _KERNEL 102 /* 103 * Used only in userland when libalias needs to keep track of all 104 * module loaded. In kernel land (kld mode) we don't need to care 105 * care about libalias modules cause it's kld to do it for us. 106 */ 107 #define DLL_LEN 32 108 struct dll { 109 char name[DLL_LEN]; /* Name of module. */ 110 void *handle; /* 111 * Ptr to shared obj obtained through 112 * dlopen() - use this ptr to get access 113 * to any symbols from a loaded module 114 * via dlsym(). 115 */ 116 SLIST_ENTRY(dll) next; 117 }; 118 119 /* Functions used with dll module. */ 120 void dll_chain_init(void); 121 void dll_chain_destroy(void); 122 int attach_dll(struct dll *); 123 void *detach_dll(char *); 124 struct dll *walk_dll_chain(void); 125 126 /* 127 * Some defines borrowed from sys/module.h used to compile a kld 128 * in userland as a shared lib. 129 */ 130 typedef enum modeventtype { 131 MOD_LOAD, 132 MOD_UNLOAD, 133 MOD_SHUTDOWN, 134 MOD_QUIESCE 135 } modeventtype_t; 136 137 typedef struct module *module_t; 138 typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *); 139 140 /* 141 * Struct for registering modules statically via SYSINIT. 142 */ 143 typedef struct moduledata { 144 const char *name; /* module name */ 145 modeventhand_t evhand; /* event handler */ 146 void *priv; /* extra data */ 147 } moduledata_t; 148 #endif /* !_KERNEL */ 149 150 #endif /* !_ALIAS_MOD_H_ */ 151