1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 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 29 /* 30 * Alias_mod.h defines the outside world interfaces for the packet aliasing 31 * modular framework 32 */ 33 34 #ifndef _ALIAS_MOD_H_ 35 #define _ALIAS_MOD_H_ 36 37 #ifdef _KERNEL 38 MALLOC_DECLARE(M_ALIAS); 39 40 /* Use kernel allocator. */ 41 #if defined(_SYS_MALLOC_H_) 42 #undef malloc 43 #define malloc(x) malloc(x, M_ALIAS, M_NOWAIT|M_ZERO) 44 #define calloc(n, x) mallocarray((n), (x), M_ALIAS, M_NOWAIT|M_ZERO) 45 #define free(x) free(x, M_ALIAS) 46 #endif 47 #endif 48 49 /* Packet flow direction flags. */ 50 #define IN 0x0001 51 #define OUT 0x0002 52 #define NODIR 0x4000 53 54 /* Working protocol flags. */ 55 #define IP 0x01 56 #define TCP 0x02 57 #define UDP 0x04 58 59 /* 60 * Data passed to protocol handler module, it must be filled 61 * right before calling find_handler() to determine which 62 * module is elegible to be called. 63 */ 64 struct alias_data { 65 struct alias_link *lnk; 66 struct in_addr *oaddr; /* Original address. */ 67 struct in_addr *aaddr; /* Alias address. */ 68 uint16_t *aport; /* Alias port. */ 69 uint16_t *sport, *dport; /* Source & destination port */ 70 uint16_t maxpktsize; /* Max packet size. */ 71 }; 72 73 /* 74 * This structure contains all the information necessary to make 75 * a protocol handler correctly work. 76 */ 77 struct proto_handler { 78 u_int pri; /* Handler priority. */ 79 int16_t dir; /* Flow direction. */ 80 uint8_t proto; /* Working protocol. */ 81 /* Fingerprint * function. */ 82 int (*fingerprint)(struct libalias *, struct alias_data *); 83 /* Aliasing * function. */ 84 int (*protohandler)(struct libalias *, struct ip *, 85 struct alias_data *); 86 TAILQ_ENTRY(proto_handler) link; 87 }; 88 89 /* End of handlers. */ 90 #define EOH .dir = NODIR 91 92 /* Functions used with protocol handlers. */ 93 int LibAliasAttachHandlers(struct proto_handler *); 94 int LibAliasDetachHandlers(struct proto_handler *); 95 int find_handler(int8_t, int8_t, struct libalias *, struct ip *, 96 struct alias_data *); 97 struct proto_handler *first_handler(void); 98 99 #ifndef _KERNEL 100 /* 101 * Used only in userland when libalias needs to keep track of all 102 * module loaded. In kernel land (kld mode) we don't need to care 103 * care about libalias modules cause it's kld to do it for us. 104 */ 105 #define DLL_LEN 32 106 struct dll { 107 char name[DLL_LEN]; /* Name of module. */ 108 void *handle; /* 109 * Ptr to shared obj obtained through 110 * dlopen() - use this ptr to get access 111 * to any symbols from a loaded module 112 * via dlsym(). 113 */ 114 SLIST_ENTRY(dll) next; 115 }; 116 117 /* Functions used with dll module. */ 118 void dll_chain_init(void); 119 void dll_chain_destroy(void); 120 int attach_dll(struct dll *); 121 void *detach_dll(char *); 122 struct dll *walk_dll_chain(void); 123 124 /* 125 * Some defines borrowed from sys/module.h used to compile a kld 126 * in userland as a shared lib. 127 */ 128 typedef enum modeventtype { 129 MOD_LOAD, 130 MOD_UNLOAD, 131 MOD_SHUTDOWN, 132 MOD_QUIESCE 133 } modeventtype_t; 134 135 typedef struct module *module_t; 136 typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *); 137 138 /* 139 * Struct for registering modules statically via SYSINIT. 140 */ 141 typedef struct moduledata { 142 const char *name; /* module name */ 143 modeventhand_t evhand; /* event handler */ 144 void *priv; /* extra data */ 145 } moduledata_t; 146 #endif /* !_KERNEL */ 147 148 #endif /* !_ALIAS_MOD_H_ */ 149