1 /* $OpenBSD: link.h,v 1.15 2013/10/19 09:00:18 deraadt Exp $ */ 2 /* $NetBSD: link.h,v 1.10 1996/01/09 00:00:11 pk Exp $ */ 3 4 /* 5 * Copyright (c) 1993 Paul Kranenburg 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by Paul Kranenburg. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 35 #ifndef _LINK_H_ 36 #define _LINK_H_ 37 38 #ifdef __ELF__ 39 #include <link_elf.h> 40 #endif 41 42 /* 43 * A `Shared Object Descriptor' describes a shared object that is needed 44 * to complete the link edit process of the object containing it. 45 * A list of such objects (chained through `sod_next') is pointed at 46 * by `sdt_sods' in the section_dispatch_table structure. 47 */ 48 49 struct sod { /* Shared Object Descriptor */ 50 long sod_name; /* name (relative to load address) */ 51 unsigned int sod_library : 1,/* Searched for by library rules */ 52 sod_reserved : 31; 53 short sod_major; /* major version number */ 54 short sod_minor; /* minor version number */ 55 long sod_next; /* next sod */ 56 }; 57 58 /* 59 * `Shared Object Map's are used by the run-time link editor (ld.so) to 60 * keep track of all shared objects loaded into a process' address space. 61 * These structures are only used at run-time and do not occur within 62 * the text or data segment of an executable or shared library. 63 */ 64 struct so_map { /* Shared Object Map */ 65 caddr_t som_addr; /* Address at which object mapped */ 66 char *som_path; /* Path to mmap'ed file */ 67 struct so_map *som_next; /* Next map in chain */ 68 struct sod *som_sod; /* Sod responsible for this map */ 69 caddr_t som_sodbase; /* Base address of this sod */ 70 unsigned int som_write : 1; /* Text is currently writable */ 71 struct _dynamic *som_dynamic; /* _dynamic structure */ 72 caddr_t som_spd; /* Private data */ 73 }; 74 75 76 /* 77 * Debug rendezvous struct. Pointer to this is set up in the 78 * target code pointed by the DT_DEBUG tag. If it is 79 * defined. 80 */ 81 struct r_debug { 82 int r_version; /* Protocol version. */ 83 struct link_map *r_map; /* Head of list of loaded objects. */ 84 85 /* 86 * This is the address of a function internal to the run-time linker, 87 * that will always be called when the linker begins to map in a 88 * library or unmap it, and again when the mapping change is complete. 89 * The debugger can set a breakpoint at this address if it wants to 90 * notice shared object mapping changes. 91 */ 92 unsigned long r_brk; 93 enum { 94 /* 95 * This state value describes the mapping change taking place 96 * when the `r_brk' address is called. 97 */ 98 RT_CONSISTENT, /* Mapping change is complete. */ 99 RT_ADD, /* Adding a new object. */ 100 RT_DELETE /* Removing an object mapping. */ 101 } r_state; 102 103 unsigned long r_ldbase; /* Base address the linker is loaded at. */ 104 }; 105 106 107 108 /* 109 * Maximum number of recognized shared object version numbers. 110 */ 111 #define MAXDEWEY 8 112 113 /* 114 * Header of the hints file. 115 */ 116 struct hints_header { 117 long hh_magic; 118 #define HH_MAGIC 011421044151 119 long hh_version; /* Interface version number */ 120 #define LD_HINTS_VERSION_1 1 121 #define LD_HINTS_VERSION_2 2 122 long hh_hashtab; /* Location of hash table */ 123 long hh_nbucket; /* Number of buckets in hashtab */ 124 long hh_strtab; /* Location of strings */ 125 long hh_strtab_sz; /* Size of strings */ 126 long hh_ehints; /* End of hints (max offset in file) */ 127 long hh_dirlist; /* Colon-separated list of srch dirs */ 128 }; 129 130 #define HH_BADMAG(hdr) ((hdr).hh_magic != HH_MAGIC) 131 132 /* 133 * Hash table element in hints file. 134 */ 135 struct hints_bucket { 136 /* namex and pathx are indices into the string table */ 137 int hi_namex; /* Library name */ 138 int hi_pathx; /* Full path */ 139 int hi_dewey[MAXDEWEY]; /* The versions */ 140 int hi_ndewey; /* Number of version numbers */ 141 #define hi_major hi_dewey[0] 142 #define hi_minor hi_dewey[1] 143 int hi_next; /* Next in this bucket */ 144 }; 145 146 #define _PATH_LD_HINTS "/var/run/ld.so.hints" 147 148 #endif /* _LINK_H_ */ 149 150