/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2017, Joyent, Inc. * Copyright 2022 Oxide Computer Company */ #ifndef _RTLD_H #define _RTLD_H /* * Global include file for the runtime linker. */ #include <sys/mman.h> #include <time.h> #include <sgs.h> #include <thread.h> #include <synch.h> #include <link.h> #include <sys/avl.h> #include <alist.h> #include <libc_int.h> #include <elfcap.h> #ifdef _SYSCALL32 #include <inttypes.h> #endif #ifdef __cplusplus extern "C" { #endif /* * We use rtld_ino_t instead of ino_t so that we can get * access to large inode values from 32-bit code. */ #ifdef _LP64 typedef ino_t rtld_ino_t; #else typedef ino64_t rtld_ino_t; #endif typedef struct rt_map Rt_map; typedef struct slookup Slookup; typedef struct sresult Sresult; /* * A binding descriptor. Establishes the binding relationship between two * objects, the caller (originator) and the dependency (destination). * * Every relationship between two objects is tracked by a binding descriptor. * This descriptor is referenced from a link-map's DEPENDS and CALLERS lists. * Note, Aplist's are diagramed to fully expose the allocations required to * establish the data structure relationships. * * Bnd_desc * ---------- * ------------| b_caller | * | | b_depend | ---------- * | | | | * Rt_map | ---------- | Rt_map * ---------- | ^ ^ | ---------- * | | <-- | | --> | | * | | -------- | | | | * | DEPENDS | ----> | | | | -------- | | * | | | | | | | | <---- | CALLERS | * | | | | --- | | | | | * | | | | --- | | | | * | | -------- | | | | * ---------- Aplist -------- ---------- * Aplist */ typedef struct { Rt_map *b_caller; /* caller (originator) of a binding */ Rt_map *b_depend; /* dependency (destination) of a */ /* binding */ uint_t b_flags; /* relationship of caller to the */ /* dependency */ } Bnd_desc; #define BND_NEEDED 0x0001 /* caller NEEDED the dependency */ #define BND_REFER 0x0002 /* caller relocation references the */ /* dependency */ #define BND_FILTER 0x0004 /* binding identifies filter, used */ /* for diagnostics only */ /* * Private structure for communication between rtld_db and rtld. * * We must bump the version number when ever an update in one of the * structures/fields that rtld_db reads is updated. This hopefully permits * rtld_db implementations of the future to recognize core files produced on * older systems and deal with these core files accordingly. * * As of version 'R_RTLDDB_VERSION <= 2' the following fields were valid for * core file examination (basically the public Link_map): * * ADDR() * NAME() * DYN() * NEXT() * PREV() * * Valid fields for R_RTLDDB_VERSION3 * * PATHNAME() * PADSTART() * PADIMLEN() * MSIZE() * FLAGS() * FLAGS1() * * Valid fields for R_RTLDDB_VERSION4 * * TLSMODID() * * Valid fields for R_RTLDDB_VERSION5 * * Added rtld_flags & FLG_RT_RELOCED to stable flags range * * Valid fields for R_RTLDDB_VERSION6 * * rtd_dynlmlst converted from a List to APlist */ #define R_RTLDDB_VERSION1 1 /* base version level - used for core */ /* file examination */ #define R_RTLDDB_VERSION2 2 /* minor revision - not relevant for */ /* core files */ #define R_RTLDDB_VERSION3 3 #define R_RTLDDB_VERSION4 4 #define R_RTLDDB_VERSION5 5 #define R_RTLDDB_VERSION6 6 #define R_RTLDDB_VERSION R_RTLDDB_VERSION6 /* current version */ typedef struct rtld_db_priv { struct r_debug rtd_rdebug; /* original r_debug structure */ Word rtd_version; /* version no. */ size_t rtd_objpad; /* padding around mmap()ed objects */ APlist **rtd_dynlmlst; /* pointer to dynlm_list pointer */ } Rtld_db_priv; #ifdef _SYSCALL32 typedef struct rtld_db_priv32 { struct r_debug32 rtd_rdebug; /* original r_debug structure */ Elf32_Word rtd_version; /* version no. */ Elf32_Word rtd_objpad; /* padding around mmap()ed objects */ Elf32_Addr rtd_dynlmlst; /* pointer to dynlm_list */ } Rtld_db_priv32; #endif /* _SYSCALL32 */ /* * External function definitions. ld.so.1 must convey information to libc in * regards to threading. libc also provides routines for atexit() and message * localization. libc provides the necessary interfaces via its RTLDINFO * structure and/or later _ld_libc() calls. * * These external functions are maintained for each link-map list, and used * where appropriate. The functions are associated with the object that * provided them, so that should the object be deleted (say, from an alternative * link-map), the functions can be removed. */ typedef struct { Rt_map *lc_lmp; /* function provider */ union { int (*lc_func)(); /* external function pointer */ uintptr_t lc_val; /* external value */ char *lc_ptr; /* external character pointer */ } lc_un; } Lc_desc; /* * Link map list definition. Link-maps are used to describe each loaded object. * Lists of these link-maps describe the various namespaces within a process. * The process executable and its dependencies are maintained on the lml_main * list. The runtime linker, and its dependencies are maintained on the * lml_rtld list. Additional lists can be created (see dlmopen()) for such * things as auditors and their dependencies. * * Each link-map list maintains an Alist of one, or more, linked lists of * link-maps. For backward compatibility, the lm_head/lm_tail elements are * initialized to the first linked-list of link-maps: * * Lm_list * ---------- * | lm_tail | ------------------------------------ * | lm_head | -------------------- | * | | | Rt_map | Rt_map * | | | ------ | ------ * | | Alist --> | | |--> | | * | | --------- | | | -- | | * | lm_lists | ----> | | | | | --> | | * | | |---------| | | | | | | * | | | lc_head | -- ------ | ------ * | | | lc_tail | ------------------ * | | |---------| * ---------- | lc_head | * | lc_tail | * |---------| * * Multiple link-map lists exist to support the addition of lazy loaded * families, filtee families, and dlopen() families. The intent of these * lists is to insure that a family of objects that are to be loaded are * fully relocatable, and hence usable, before they become part of the main * (al_data[0]) link-map control list. This main link-map control list is * the only list in existence when control is transferred to user code. * * During process initialization, the dynamic executable and its non-lazy * dependencies are maintained on al_data[0]. If a new object is loaded, then * this object is added to the next available control list [1], typically * al_data[1]. Any dependencies of this object that have not already been * loaded are added to the same control list. Once all of the objects on the * new control list have been successfully relocated, the objects are moved from * the new control list to the highest control list to which objects of the new * control list bound to, typically al_data[1] to al_data[0]. * * Each loading scenario can be broken down as follows: * * setup() - only the initial link-map control list is used: * i. create al_data[0] * ii. add new link-map for main on al_data[0] * iii. analyze al_data[0] to add all non-lazy dependencies * iv. relocate al_data[0] dependencies. * * dlopen() - the initiator can only be the initial link-map control list: * i. create al_data[1] from caller al_data[0] * ii. add new link-map for the dlopen'ed object on al_data[1] * iii. analyze al_data[1] to add all non-lazy dependencies * iv. relocate al_data[1] dependencies, and move to al_data[0]. * * filtee and lazy loading processing - the initiator can be any link-map * control list that is being relocated: * i. create al_data[y] from caller al_data[x] * ii. add new link-map for the new object on al_data[y] * iii. analyze al_data[y] to add all non-lazy dependencies * iv. relocate al_data[y] dependencies, and move to al_data[x]. * * This Alist therefore maintains a stack of link-map control lists. The newest * link-map control list can locate symbols within any of the former lists, * however, control is not passed to a former list until the newest lists * processing is complete. Thus, objects can't bind to new objects until they * have been fully analyzed and relocated. * * [1] Note, additional link-map control list creation occurs after the head * link-map object (typically the dynamic executable) has been relocated. This * staging is required to satisfy the binding requirements of copy relocations. * Copy relocations, effectively, transfer the bindings of the copied data * (say _iob in libc.so.1) to the copy location (_iob in the application). * Thus an object that might bind to the original copy data must be redirected * to the copy reference. As the knowledge of a copy relocation having taken * place is only known after relocating the application, link-map control list * additions are suspended until after this relocation has completed. */ typedef struct { Rt_map *lc_head; Rt_map *lc_tail; APlist *lc_now; /* pending promoted bind-now objects */ uint_t lc_flags; } Lm_cntl; #define LMC_FLG_ANALYZING 0x01 /* control list is being analyzed */ #define LMC_FLG_RELOCATING 0x02 /* control list is being relocated */ #define LMC_FLG_REANALYZE 0x04 /* repeat analysis (established when */ /* interposers are added */ struct lm_list { /* * BEGIN: Exposed to rtld_db - don't move, don't delete */ Rt_map *lm_head; /* linked list pointers to active */ Rt_map *lm_tail; /* link-map list */ APlist *lm_handle; /* not used by rtld_db - but spacing */ /* is required for flags */ Word lm_flags; /* * END: Exposed to rtld_db - don't move, don't delete */ Alist *lm_rti; /* list of RTLDINFO tables */ Audit_list *lm_alp; /* audit list descriptor */ avl_tree_t *lm_fpavl; /* avl tree of objects loaded */ Alist *lm_lists; /* active and pending link-map lists */ char ***lm_environ; /* pointer to environment array */ Word lm_tflags; /* transferable flags */ uint_t lm_obj; /* total number of objs on link-map */ uint_t lm_init; /* new obj since last init processing */ uint_t lm_lazy; /* number of objects with pending */ /* lazy dependencies */ uint_t lm_tls; /* new obj that require TLS */ uint_t lm_lmid; /* unique link-map list identifier, */ char *lm_lmidstr; /* and associated diagnostic string */ Alist *lm_aud_cookies; /* local auditor cookies */ Lc_desc lm_lcs[CI_MAX]; /* external libc functions */ }; #ifdef _SYSCALL32 struct lm_list32 { /* * BEGIN: Exposed to rtld_db - don't move, don't delete */ Elf32_Addr lm_head; Elf32_Addr lm_tail; Elf32_Addr lm_handle; Elf32_Word lm_flags; /* * END: Exposed to rtld_db - don't move, don't delete */ Elf32_Addr lm_rti; Elf32_Addr lm_fpavl; Elf32_Addr lm_lists; Elf32_Addr lm_environ; Elf32_Word lm_tflags; uint_t lm_obj; uint_t lm_init; uint_t lm_lazy; uint_t lm_tls; uint_t lm_lmid; Elf32_Addr lm_lmidstr; Elf32_Addr lm_aud_cookies; Elf32_Addr lm_lcs[CI_MAX]; }; #endif /* _SYSCALL32 */ /* * Possible Link_map list flags (Lm_list.lm_flags) */ /* * BEGIN: Exposed to rtld_db - don't move, don't delete */ #define LML_FLG_BASELM 0x00000001 /* primary link-map */ #define LML_FLG_RTLDLM 0x00000002 /* rtld link-map */ /* * END: Exposed to rtld_db - don't move, don't delete */ #define LML_FLG_ACTAUDIT 0x00000004 /* audit activity posted */ #define LML_FLG_PLTREL 0x00000008 /* deferred plt relocation */ /* initialization (ld.so.1 */ /* only) */ #define LML_FLG_HOLDLOCK 0x00000010 /* hold the rtld mutex lock */ #define LML_FLG_ENVIRON 0x00000020 /* environ var initialized */ #define LML_FLG_INTRPOSE 0x00000040 /* interposing objs on list */ #define LML_FLG_LOCAUDIT 0x00000080 /* local auditors exists for */ /* this link-map list */ #define LML_FLG_LOADAVAIL 0x00000100 /* load anything available */ #define LML_FLG_IGNRELERR 0x00000200 /* ignore relocation errors - */ /* internal for crle(1) */ #define LML_FLG_STARTREL 0x00000400 /* relocation started */ #define LML_FLG_ATEXIT 0x00000800 /* atexit processing */ #define LML_FLG_OBJADDED 0x00001000 /* object(s) added */ #define LML_FLG_OBJDELETED 0x00002000 /* object(s) deleted */ #define LML_FLG_OBJREEVAL 0x00004000 /* existing object(s) needs */ /* tsort reevaluation */ #define LML_FLG_INTRPOSETSORT 0x00008000 /* interpose tsorting done */ #define LML_FLG_AUDITNOTIFY 0x00010000 /* audit consistent required */ #define LML_FLG_GROUPSEXIST 0x00020000 /* local groups exist */ #define LML_FLG_TRC_LDDSTUB 0x00100000 /* identify lddstub */ #define LML_FLG_TRC_ENABLE 0x00200000 /* tracing enabled (ldd) */ #define LML_FLG_TRC_WARN 0x00400000 /* print warnings for undefs */ #define LML_FLG_TRC_VERBOSE 0x00800000 /* verbose (versioning) trace */ #define LML_FLG_TRC_SEARCH 0x01000000 /* trace search paths */ #define LML_FLG_TRC_UNREF 0x02000000 /* trace unreferenced */ /* dependencies */ #define LML_FLG_TRC_UNUSED 0x04000000 /* trace unused dependencies */ #define LML_FLG_TRC_INIT 0x08000000 /* print .init order */ #define LML_FLG_TRC_NOUNRESWEAK 0x10000000 /* unresolved weak references */ /* are not allowed */ #define LML_FLG_TRC_NOPAREXT 0x20000000 /* unresolved PARENT/EXTERN */ /* references are not */ /* allowed */ #define LML_MSK_TRC 0xfff00000 /* tracing mask */ /* * Possible Link_map transferable flags (Lm_list.lm_tflags), i.e., link-map * list flags that can be propagated to any new link-map list created. */ #define LML_TFLG_NOLAZYLD 0x00000001 /* lazy loading disabled */ #define LML_TFLG_NODIRECT 0x00000002 /* direct bindings disabled */ #define LML_TFLG_NOAUDIT 0x00000004 /* auditing disabled */ #define LML_TFLG_LOADFLTR 0x00000008 /* trigger filtee loading */ #define LML_TFLG_AUD_PREINIT 0x00001000 /* preinit (audit) exists */ #define LML_TFLG_AUD_OBJSEARCH 0x00002000 /* objsearch (audit) exists */ #define LML_TFLG_AUD_OBJOPEN 0x00004000 /* objopen (audit) exists */ #define LML_TFLG_AUD_OBJFILTER 0x00008000 /* objfilter (audit) exists */ #define LML_TFLG_AUD_OBJCLOSE 0x00010000 /* objclose (audit) exists */ #define LML_TFLG_AUD_SYMBIND 0x00020000 /* symbind (audit) exists */ #define LML_TFLG_AUD_PLTENTER 0x00040000 /* pltenter (audit) exists */ #define LML_TFLG_AUD_PLTEXIT 0x00080000 /* pltexit (audit) exists */ #define LML_TFLG_AUD_ACTIVITY 0x00100000 /* activity (audit) exists */ /* * NOTE: Each auditing module establishes a set of audit flags, AFLAGS(), that * define the auditing interfaces the module offers. These auditing flags are * the LML_TFLG_AUD_ flags defined above. Global auditors result in setting * the lm_tflags too. Local auditors only use the AFLAGS(). All tests for * auditing inspect the lm_tflags and AFLAGS() for a specific auditing * interface, and thus use the same flag to test for both types of auditors. */ #define LML_TFLG_AUD_MASK 0x0ffff000 /* audit interfaces mask */ /* * Define a Group Handle. * * The capability of ld.so.1 to associate a group of objects, look for symbols * within that group, ensure that groups are isolated from one another (with * regard to relocations), and to unload a group, centers around a handle. * * Dependencies can be added to an existing handle as the dependencies are * lazily loaded. The core dependencies on the handle are the ldd(1) list of * the referenced object. * * Handles can be created from: * * - a dlopen() request. This associates a caller to a reference object, * and the referenced objects dependencies. This group of objects can * then be inspected for symbols (dlsym()). * - a filtering request. This associates a filter (caller) to a referenced * object (filtee). The redirection of filter symbols to their filtee * counterpart is essentially a dlsym() using the filtee's handle. * * The handle created for these events is referred to as a public handle. This * handle tracks the referenced object, all of the dependencies of the * referenced object, and the caller (parent). * * Presently, an object may have two handles, one requested with RTLD_FIRST * and one without. * * A handle may be referenced by any number of callers (parents). A reference * count tracks the number. A dlclose() operation drops the reference count, * and when the count is zero, the handle is used to determine the family of * objects to unload. As bindings may occur to objects on the handle from * other handles, it may not be possible to remove a complete family of objects * or the handle itself. Handles in this state are moved to an orphan list. * A handle on the orphan list is taken off the orphan list if the associated * object is reopened. Otherwise, the handle remains on the orphan list for * the duration of the process. The orphan list is inspected any time objects * are unloaded, to determine if the orphaned objects can also be unloaded. * * Handles can also be created for internal uses: * * - to promote objects to RTLD_NOW. * - to establish families for symbol binding fallback, required when lazy * loadable objects are still pending. * * The handle created for these events is referred to as a private handle. This * handle does not need to track the caller (parent), and because of this, does * not need to be considered during dlclose() operations, as the handle can not * be referenced by callers outside of the referenced objects family. * * Note, a private handle is essentially a subset of a public handle. Should * an internal operation require a private handle, and a public handle already * exist, the public handle can be used. Should an external operation require * a public handle, and a private handle exist, the private handle is promoted * to a public handle. Any handle that gets created will remain in existence * for the life time of the referenced object. * * Objects can be dlopened using RTLD_NOW. This attribute requires that all * relocations of the object, and its dependencies are processed immediately, * before return to the caller. Typically, an object is loaded without * RTLD_NOW, and procedure linkage relocations are satisfied when their * associated function is first called. If an object is already loaded, and an * RTLD_NOW request is made, then the object, and its dependencies, most undergo * additional relocation processing. This promotion from lazy binding to * immediate binding is carried out using handles, as the handle defines the * dependencies that must be processed. * * To ensure that objects within a lazy loadable environment can be relocated, * no matter whether the objects have their dependencies described completely, * a symbol lookup fallback is employed. Any pending lazy loadable objects are * loaded, and a handle established to search the object and it's dependencies * for the required symbol. * * A group handle (and its associated group descriptors), is referenced from * a link-map's HANDLES and GROUPS lists. Note, Aplist's are diagramed to * fully expose the allocations required to establish the data structure * relationships. * * Grp_desc * Alist * ----------- * --> | | * | |-----------| * | | gd_depend | --------- * | | | | * | |-----------| | * --------|--- | gd_depend | | * | | | (parent) | | * | | |-----------| | * | | | gd_depend | | * | | | | | * | | | | | * | | ----------- | * | | | * | | Grp_hdl | * | | ----------- | * | -- | gh_depends | | * | --------- | gh_ownlmp | | * | | | | | * | | | | | * | | | | | * Rt_map | | ------------ | Rt_map * ---------- | | ^ ^ | ---------- * | | <- | | | --> | | * | | <--- -------- | | | | * | HANDLES | ----> | | | | -------- | | * | | | | | | | | <---- | GROUPS | * | | | | --- | | | | | * | | | | --- | | | | * | | -------- | | | | * ---------- Aplist -------- ---------- * Aplist */ typedef struct { Alist *gh_depends; /* handle dependency list */ Rt_map *gh_ownlmp; /* handle owners link-map */ Lm_list *gh_ownlml; /* handle owners link-map list */ uint_t gh_refcnt; /* handle reference count */ uint_t gh_flags; /* handle flags (GPH_ values) */ } Grp_hdl; /* * Define the two categories of handle. */ #define GPH_PUBLIC 0x0001 /* handle returned to caller(s) */ #define GPH_PRIVATE 0x0002 /* handle used internally */ /* * Define any flags that affects how the handle is used. */ #define GPH_ZERO 0x0010 /* special handle for dlopen(0) */ #define GPH_LDSO 0x0020 /* special handle for ld.so.1 */ #define GPH_FIRST 0x0040 /* dlsym() can only use originating */ /* dependency */ #define GPH_FILTEE 0x0080 /* handle identifies a filtee, used */ /* for diagnostics only */ /* * Define any state that is associated with the handle. */ #define GPH_INITIAL 0x0100 /* handle is initialized */ /* * Define a Group Descriptor. * * Each dependency associated with a group handle is maintained by a group * descriptor. The descriptor defines the associated dependency together with * flags that indicate how the dependency can be used. */ typedef struct { Rt_map *gd_depend; /* dependency */ uint_t gd_flags; /* dependency flags (GPD_ values) */ } Grp_desc; #define GPD_DLSYM 0x0001 /* dependency available to dlsym() */ #define GPD_RELOC 0x0002 /* dependency available to satisfy */ /* relocation binding */ #define GPD_ADDEPS 0x0004 /* dependencies of this dependency */ /* should be added to handle */ #define GPD_PARENT 0x0008 /* dependency is a parent */ #define GPD_FILTER 0x0010 /* dependency is our filter */ #define GPD_REMOVE 0x0100 /* descriptor is a candidate for */ /* removal from the group */ /* * Define threading structures. For compatibility with libthread (T1_VERSION 1 * and TI_VERSION 2) our locking structure is sufficient to hold a mutex or a * readers/writers lock. */ typedef struct { union { mutex_t l_mutex; rwlock_t l_rwlock; } u; } Rt_lock; typedef cond_t Rt_cond; /* * Define a dynamic section information descriptor. This parallels the entries * in the .dynamic section and holds auxiliary information to implement lazy * loading and filtee processing. */ typedef struct { uint_t di_flags; void *di_info; const char *di_name; } Dyninfo; #define FLG_DI_STDFLTR 0x00001 /* .dynamic entry for DT_FILTER */ #define FLG_DI_AUXFLTR 0x00002 /* .dynamic entry for DT_AUXILIARY */ #define FLG_DI_SYMFLTR 0x00004 /* .dynamic entry for DT_SYMFILTER */ /* and DT_SYMAUXILIARY */ #define MSK_DI_FILTER 0x0000f /* mask for all filter possibilities */ #define FLG_DI_POSFLAG1 0x00010 /* .dynamic entry for DT_POSFLAG_1 */ #define FLG_DI_NEEDED 0x00020 /* .dynamic entry for DT_NEEDED */ #define FLG_DI_REGISTER 0x00040 /* .dynamic entry for DT_REGISTER */ #define FLG_DI_IGNORE 0x00080 /* .dynamic entry should be ignored */ #define FLG_DI_LAZY 0x00100 /* lazy needed entry, preceded by */ /* DF_P1_LAZYLOAD (DT_POSFLAG_1) */ #define FLG_DI_GROUP 0x00200 /* group needed entry, preceded by */ /* DF_P1_GROUPPERM (DT_POSFLAG_1) */ #define FLG_DI_DEFERRED 0x00400 /* deferred needed entry, preceded by */ /* DF_P1_DEFERRED (DT_POSFLAG_1) */ #define FLG_DI_LAZYFAIL 0x01000 /* the lazy loading of this entry */ /* failed */ #define FLG_DI_LDD_DONE 0x02000 /* entry has been processed (ldd) */ #define FLG_DI_DEF_DONE 0x04000 /* entry has been processed (dlinfo) */ /* * Data structure to track AVL tree of pathnames. This structure provides the * basis of both the "not-found" node tree, and the "full-path" node tree. Both * of these trees persist for the life of a process, although the "not-found" * tree may be moved aside during a dlopen() or dlsym() fall back operation. */ typedef struct { const char *pn_name; /* path name */ avl_node_t pn_avl; /* avl book-keeping (see SGSOFFSETOF) */ uint_t pn_hash; /* path name hash value */ } PathNode; /* * Data structure to track AVL tree for full path names of objects that are * loaded into memory. */ typedef struct { PathNode fpn_node; /* path node */ Rt_map *fpn_lmp; /* object link-map */ } FullPathNode; /* * A given link-map can hold either a supplier or receiver copy * relocation list, but not both. This union is used to overlap * the space used for the two lists. */ typedef union { Alist *rtc_r; /* receiver list (Rel_copy) */ APlist *rtc_s; /* supplier list (Rt_map *) */ } Rt_map_copy; /* * Link-map definition. */ struct rt_map { /* * BEGIN: Exposed to rtld_db - don't move, don't delete */ Link_map rt_public; /* public data */ const char *rt_pathname; /* full pathname of loaded object */ ulong_t rt_padstart; /* start of image (including padding) */ ulong_t rt_padimlen; /* size of image (including padding */ ulong_t rt_msize; /* total memory reservation range */ uint_t rt_flags; /* state flags, see FLG below */ uint_t rt_flags1; /* state flags1, see FL1 below */ ulong_t rt_tlsmodid; /* TLS module id */ /* * END: Exposed to rtld_db - don't move, don't delete */ APlist *rt_alias; /* list of linked file names */ APlist *rt_fpnode; /* list of FullPathNode AVL nodes */ char *rt_runpath; /* LD_RUN_PATH and its equivalent */ Alist *rt_runlist; /* Pdesc structures */ APlist *rt_depends; /* list of dependencies */ APlist *rt_callers; /* list of callers */ APlist *rt_handles; /* dlopen handles */ APlist *rt_groups; /* groups we're a member of */ struct fct *rt_fct; /* file class table for this object */ void *rt_priv; /* private data, object type specific */ Lm_list *rt_list; /* link map list we belong to */ uint_t rt_objfltrndx; /* object filtees .dynamic index */ uint_t rt_symsfltrcnt; /* number of standard symbol filtees */ uint_t rt_symafltrcnt; /* number of auxiliary symbol filtees */ int rt_mode; /* usage mode, see RTLD mode flags */ int rt_sortval; /* temporary buffer to traverse graph */ uint_t rt_cycgroup; /* cyclic group */ dev_t rt_stdev; /* device id and inode number for .so */ rtld_ino_t rt_stino; /* multiple inclusion checks */ const char *rt_origname; /* original pathname of loaded object */ size_t rt_dirsz; /* and its size */ size_t rt_lmsize; /* size of the link-map allocation */ Rt_map_copy rt_copy; /* list of copy relocations */ Audit_desc *rt_auditors; /* audit descriptor array */ Audit_info *rt_audinfo; /* audit information descriptor */ Syminfo *rt_syminfo; /* elf .syminfo section - here */ /* because it is checked in */ /* common code */ Addr *rt_initarray; /* .init_array table */ Addr *rt_finiarray; /* .fini_array table */ Addr *rt_preinitarray; /* .preinit_array table */ mmapobj_result_t *rt_mmaps; /* array of mapping information */ uint_t rt_mmapcnt; /* and associated number */ uint_t rt_initarraysz; /* size of .init_array table */ uint_t rt_finiarraysz; /* size of .fini_array table */ uint_t rt_preinitarraysz; /* size of .preinit_array table */ Dyninfo *rt_dyninfo; /* .dynamic information descriptors */ uint_t rt_dyninfocnt; /* count of dyninfo entries */ uint_t rt_relacount; /* no. of RELATIVE relocations */ uint_t rt_idx; /* hold index within linkmap list */ uint_t rt_lazy; /* number of lazy dependencies */ /* pending */ Cap *rt_cap; /* capabilities data */ Capchain *rt_capchain; /* capabilities chain data */ uint_t rt_cntl; /* link-map control list we belong to */ uint_t rt_aflags; /* auditor flags, see LML_TFLG_AUD_ */ Rt_cond rt_cv; /* for waiting on flags changes */ Rt_lock rt_lock; /* for coordinating flags changes */ /* address of _init */ thread_t rt_init_thread; /* thread id in this lm's _init */ void (*rt_init)(void); /* address of _fini */ void (*rt_fini)(void); /* link map symbol interpreter */ int (*rt_symintp)(Slookup *, Sresult *, uint_t *, int *); }; #ifdef _SYSCALL32 /* * Structure to allow 64-bit rtld_db to read 32-bit processes out of procfs. */ typedef union { uint32_t rtc_r; uint32_t rtc_s; } Rt_map_copy32; typedef struct rt_map32 { /* * BEGIN: Exposed to rtld_db - don't move, don't delete */ Link_map32 rt_public; uint32_t rt_pathname; uint32_t rt_padstart; uint32_t rt_padimlen; uint32_t rt_msize; uint32_t rt_flags; uint32_t rt_flags1; uint32_t rt_tlsmodid; /* * END: Exposed to rtld_db - don't move, don't delete */ uint32_t rt_alias; uint32_t rt_fpnode; uint32_t rt_runpath; uint32_t rt_runlist; uint32_t rt_depends; uint32_t rt_callers; uint32_t rt_handles; uint32_t rt_groups; uint32_t rt_fct; uint32_t rt_priv; uint32_t rt_list; uint32_t rt_objfltrndx; uint32_t rt_symsfltrcnt; uint32_t rt_symafltrcnt; int32_t rt_mode; int32_t rt_sortval; uint32_t rt_cycgroup; uint32_t rt_stdev; uint32_t rt_stino; uint32_t rt_origname; uint32_t rt_dirsz; Rt_map_copy32 rt_copy; uint32_t rt_auditors; uint32_t rt_audinfo; uint32_t rt_syminfo; uint32_t rt_initarray; uint32_t rt_finiarray; uint32_t rt_preinitarray; uint32_t rt_mmaps; uint32_t rt_mmapcnt; uint32_t rt_initarraysz; uint32_t rt_finiarraysz; uint32_t rt_preinitarraysz; uint32_t rt_dyninfo; uint32_t rt_dyninfocnt; uint32_t rt_relacount; uint32_t rt_idx; uint32_t rt_lazy; uint32_t rt_cap; uint32_t rt_capchain; uint32_t rt_cntl; uint32_t rt_aflags; uint32_t rt_init; uint32_t rt_fini; uint32_t rt_symintp; } Rt_map32; #endif /* _SYSCALL32 */ /* * Link map state flags. */ /* * BEGIN: Exposed to rtld_db - don't move, don't delete */ #define FLG_RT_ISMAIN 0x00000001 /* object represents main executable */ #define FLG_RT_IMGALLOC 0x00000002 /* image is allocated (not mmap'ed) */ /* * Available for r_debug version >= R_RTLDDB_VERSION5 */ #define FLG_RT_RELOCED 0x00000004 /* object has been relocated */ /* * END: Exposed to rtld_db - don't move, don't delete */ #define FLG_RT_SETGROUP 0x00000008 /* group establishment required */ #define FLG_RT_CAP 0x00000010 /* process $CAPABILITY expansion */ #define FLG_RT_OBJECT 0x00000020 /* object processing (ie. .o's) */ #define FLG_RT_NEWLOAD 0x00000040 /* object is newly loaded */ #define FLG_RT_NODUMP 0x00000080 /* object can't be dldump(3C)'ed */ #define FLG_RT_DELETE 0x00000100 /* object can be deleted */ #define FLG_RT_ANALYZED 0x00000200 /* object has been analyzed */ #define FLG_RT_INITDONE 0x00000400 /* objects .init has been completed */ #define FLG_RT_TRANS 0x00000800 /* object is acting as a translator */ #define FLG_RT_FIXED 0x00001000 /* image location is fixed */ #define FLG_RT_PRELOAD 0x00002000 /* object was preloaded */ #define FLG_RT_ALTER 0x00004000 /* alternative object used */ #define FLG_RT_LOADFLTR 0x00008000 /* trigger filtee loading */ #define FLG_RT_AUDIT 0x00010000 /* object is an auditor */ #define FLG_RT_MODESET 0x00020000 /* MODE() has been initialized */ #define FLG_RT_ANALZING 0x00040000 /* object is being analyzed */ #define FLG_RT_INITFRST 0x00080000 /* execute .init first */ #define FLG_RT_NOOPEN 0x00100000 /* dlopen() not allowed */ #define FLG_RT_FINICLCT 0x00200000 /* fini has been collected (tsort) */ #define FLG_RT_INITCALL 0x00400000 /* objects .init has been called */ #define FLG_RT_OBJINTPO 0x00800000 /* object is a global interposer */ #define FLG_RT_SYMINTPO 0x01000000 /* object contains symbol interposer */ #define MSK_RT_INTPOSE 0x01800000 /* mask for all interposer */ /* possibilities */ #define FLG_RT_MOVE 0x02000000 /* object needs move operation */ #define FLG_RT_RELOCING 0x04000000 /* object is being relocated */ #define FLG_RT_REGSYMS 0x08000000 /* object has DT_REGISTER entries */ #define FLG_RT_INITCLCT 0x10000000 /* init has been collected (tsort) */ #define FLG_RT_PUBHDL 0x20000000 /* generate a handle for this object */ #define FLG_RT_PRIHDL 0x40000000 /* either public or private */ #define FL1_RT_COPYTOOK 0x00000001 /* copy relocation taken */ #define FL1_RT_ALTCHECK 0x00000002 /* alternative system capabilities */ /* checked */ #define FL1_RT_ALTCAP 0x00000004 /* alternative system capabilities */ /* should be used */ #define FL1_RT_CONFSET 0x00000008 /* object was loaded by crle(1) */ #define FL1_RT_NODEFLIB 0x00000010 /* ignore default library search */ #define FL1_RT_ENDFILTE 0x00000020 /* filtee terminates filters search */ #define FL1_RT_DISPREL 0x00000040 /* object has *disp* relocation */ #define FL1_RT_DTFLAGS 0x00000080 /* DT_FLAGS element exists */ #define FL1_RT_LDDSTUB 0x00000100 /* identify lddstub */ #define FL1_RT_NOINIFIN 0x00000200 /* no .init or .fini exists */ #define FL1_RT_USED 0x00000400 /* symbol referenced from this object */ #define FL1_RT_SYMBOLIC 0x00000800 /* DF_SYMBOLIC was set - use */ /* symbolic sym resolution */ #define FL1_RT_OBJSFLTR 0x00001000 /* object is acting as a standard */ #define FL1_RT_OBJAFLTR 0x00002000 /* or auxiliary filter */ #define FL1_RT_SYMSFLTR 0x00004000 /* symbol is acting as a standard */ #define FL1_RT_SYMAFLTR 0x00008000 /* or auxiliary filter */ #define MSK_RT_FILTER 0x0000f000 /* mask for all filter possibilities */ #define FL1_RT_TLSADD 0x00010000 /* objects TLS has been registered */ #define FL1_RT_TLSSTAT 0x00020000 /* object requires static TLS */ #define FL1_RT_DIRECT 0x00040000 /* object has DIRECT bindings enabled */ #define FL1_RT_GLOBAUD 0x00080000 /* establish global auditing */ #define FL1_RT_DEPAUD 0x00100000 /* audit library from DT_DEPAUDIT */ /* * Flags for the tls_modactivity() routine */ #define TM_FLG_MODADD 0x01 /* call tls_modadd() interface */ #define TM_FLG_MODREM 0x02 /* call tls_modrem() interface */ /* * Macros for getting to exposed, link_map data (R_RTLDDB_VERSION <= 2). */ #define ADDR(X) ((X)->rt_public.l_addr) #define NAME(X) ((X)->rt_public.l_name) #define DYN(X) ((X)->rt_public.l_ld) #define NEXT(X) ((X)->rt_public.l_next) #define PREV(X) ((X)->rt_public.l_prev) #define REFNAME(X) ((X)->rt_public.l_refname) /* * An Rt_map starts with a Link_map, followed by other information. * ld.so.1 allocates Rt_map structures, and then casts them to Link_map, * and back, depending on context. * * On some platforms, Rt_map can have a higher alignment requirement * than Link_map. On such platforms, the cast from Link_map to Rt_map will * draw an E_BAD_PTR_CAST_ALIGN warning from lint. Since we allocate * the memory as the higher alignment Rt_map, we know that this is a safe * conversion. The LINKMAP_TO_RTMAP macro is used to handle the conversion * in a manner that satisfies lint. */ #ifdef lint #define LINKMAP_TO_RTMAP(X) (Rt_map *)(void *)(X) #else #define LINKMAP_TO_RTMAP(X) (Rt_map *)(X) #endif /* * Convenience macros for the common case of using * NEXT()/PREV() and casting the result to (Rt_map *) */ #define NEXT_RT_MAP(X) LINKMAP_TO_RTMAP(NEXT(X)) #define PREV_RT_MAP(X) LINKMAP_TO_RTMAP(PREV(X)) /* * Macros for getting to exposed, link_map data (R_RTLDDB_VERSION3). */ #define PATHNAME(X) ((X)->rt_pathname) #define PADSTART(X) ((X)->rt_padstart) #define PADIMLEN(X) ((X)->rt_padimlen) #define MSIZE(X) ((X)->rt_msize) #define FLAGS(X) ((X)->rt_flags) #define FLAGS1(X) ((X)->rt_flags1) /* * Macros for getting to exposed, link_map data (R_RTLDDB_VERSION4). */ #define TLSMODID(X) ((X)->rt_tlsmodid) /* * Macros for getting to unexposed, link-map data. */ #define LMSIZE(X) ((X)->rt_lmsize) #define AFLAGS(X) ((X)->rt_aflags) #define ALIAS(X) ((X)->rt_alias) #define FPNODE(X) ((X)->rt_fpnode) #define INIT(X) ((X)->rt_init) #define FINI(X) ((X)->rt_fini) #define RPATH(X) ((X)->rt_runpath) #define RLIST(X) ((X)->rt_runlist) #define DEPENDS(X) ((X)->rt_depends) #define CALLERS(X) ((X)->rt_callers) #define HANDLES(X) ((X)->rt_handles) #define GROUPS(X) ((X)->rt_groups) #define FCT(X) ((X)->rt_fct) #define SYMINTP(X) ((X)->rt_symintp) #define LIST(X) ((X)->rt_list) #define OBJFLTRNDX(X) ((X)->rt_objfltrndx) #define SYMSFLTRCNT(X) ((X)->rt_symsfltrcnt) #define SYMAFLTRCNT(X) ((X)->rt_symafltrcnt) #define MODE(X) ((X)->rt_mode) #define SORTVAL(X) ((X)->rt_sortval) #define CYCGROUP(X) ((X)->rt_cycgroup) #define STDEV(X) ((X)->rt_stdev) #define STINO(X) ((X)->rt_stino) #define ORIGNAME(X) ((X)->rt_origname) #define DIRSZ(X) ((X)->rt_dirsz) #define COPY_R(X) ((X)->rt_copy.rtc_r) #define COPY_S(X) ((X)->rt_copy.rtc_s) #define AUDITORS(X) ((X)->rt_auditors) #define AUDINFO(X) ((X)->rt_audinfo) #define SYMINFO(X) ((X)->rt_syminfo) #define INITARRAY(X) ((X)->rt_initarray) #define FINIARRAY(X) ((X)->rt_finiarray) #define PREINITARRAY(X) ((X)->rt_preinitarray) #define MMAPS(X) ((X)->rt_mmaps) #define MMAPCNT(X) ((X)->rt_mmapcnt) #define INITARRAYSZ(X) ((X)->rt_initarraysz) #define FINIARRAYSZ(X) ((X)->rt_finiarraysz) #define PREINITARRAYSZ(X) ((X)->rt_preinitarraysz) #define DYNINFO(X) ((X)->rt_dyninfo) #define DYNINFOCNT(X) ((X)->rt_dyninfocnt) #define RELACOUNT(X) ((X)->rt_relacount) #define IDX(X) ((X)->rt_idx) #define LAZY(X) ((X)->rt_lazy) #define CNTL(X) ((X)->rt_cntl) #define CAP(X) ((X)->rt_cap) #define CAPCHAIN(X) ((X)->rt_capchain) /* * Flags for tsorting. */ #define RT_SORT_FWD 0x01 /* topological sort (.fini) */ #define RT_SORT_REV 0x02 /* reverse topological sort (.init) */ #define RT_SORT_DELETE 0x10 /* process FLG_RT_DELETE objects */ /* only (called via dlclose()) */ #define RT_SORT_INTPOSE 0x20 /* process interposer objects */ /* * Flags for lookup_sym (and hence find_sym) routines. */ #define LKUP_DEFT 0x0000 /* simple lookup request */ #define LKUP_SPEC 0x0001 /* special ELF lookup (allows address */ /* resolutions to plt[] entries) */ /* 0x2 was previously used as part of a.out support */ #define LKUP_FIRST 0x0004 /* lookup symbol in first link map */ /* only */ #define LKUP_COPY 0x0008 /* lookup symbol for a COPY reloc, do */ /* not bind to symbol at head */ #define LKUP_STDRELOC 0x0010 /* lookup originates from a standard */ /* relocation (elf_reloc()) */ #define LKUP_SELF 0x0020 /* lookup symbol in ourself - undef */ /* is valid */ #define LKUP_WEAK 0x0040 /* relocation reference is weak */ #define LKUP_NEXT 0x0080 /* request originates from RTLD_NEXT */ #define LKUP_NODESCENT 0x0100 /* don't descend through dependencies */ #define LKUP_NOFALLBACK 0x0200 /* don't fall back to loading */ /* pending lazy dependencies */ #define LKUP_DIRECT 0x0400 /* direct binding request */ #define LKUP_SYMNDX 0x0800 /* establish symbol index */ #define LKUP_SINGLETON 0x1000 /* search for a singleton symbol */ #define LKUP_STANDARD 0x2000 /* standard lookup - originated from */ /* head link-map element */ #define LKUP_WORLD 0x4000 /* ensure world lookup */ #define LKUP_DLSYM 0x8000 /* lookup stems from dlsym() request */ /* * For the runtime linker to perform a symbol search, a number of data items * related to the search are required. An Slookup data structure is used to * convey this data to lookup_sym(), and in special cases, to other core * routines that provide the implementation details for lookup_sym() * * The symbol name (sl_name), the caller (sl_cmap), and the link-map from which * to start the search (sl_imap) are fundamental to the symbol search. The * initial search link-map might get modified by the core routines that provide * the implementation details for lookup_sym(). This modification accommodates * requirements such as processing a handle, direct binding and interposition. * The association between the caller and the potential destination also * determines whether the destination is a candidate to search. * * The lookup identifier (sl_id) is used to identify a runtime linker operation. * Within this operation, any lazy loads that fail are not re-examined. This * technique keeps the overhead of processing a failed lazy load to a minimum. * * Symbol searches that originate from a relocation record are accompanied by * the relocation index (sl_rsymndx), the symbol reference (sl_rsym) and * possibly the relocation type (sl_rtype). This data provides for determining * lazy loading, direct binding, and special symbol processing requirements * such as copy relocations and singleton lookup. * * The symbols hash value is computed by lookup_sym, and propagated throughout * the search engine. Note, occasionally the Slookup data is passed to a core * routine that provides the implementation details for lookup_sym(), ie. * elf_find_sym(), in which case the caller must initialize the hash value. * * The symbols binding information is established by lookup_sym() when the * symbols relocation type is supplied. Weak bindings allow relocations to * be set to zero should a symbol lookup fail. * * The flags allow the caller to control aspects of the search, including the * interpretation of copy relocations, etc. Note, a number of flag settings * are established in lookup_sym() from attributes of the symbol reference. */ struct slookup { const char *sl_name; /* symbol name */ Rt_map *sl_cmap; /* callers link-map */ Rt_map *sl_imap; /* initial link-map to search */ ulong_t sl_id; /* identifier for this lookup */ ulong_t sl_hash; /* symbol hash value */ ulong_t sl_rsymndx; /* referencing reloc symndx */ Sym *sl_rsym; /* referencing symbol */ uchar_t sl_rtype; /* relocation type associate with */ /* symbol */ uchar_t sl_bind; /* symbols binding (returned) */ uint_t sl_flags; /* lookup flags */ }; #define SLOOKUP_INIT(sl, name, cmap, imap, id, hash, rsymndx, rsym, rtype, \ flags) \ (void) (sl.sl_name = (name), sl.sl_cmap = (cmap), sl.sl_imap = (imap), \ sl.sl_id = (id), sl.sl_hash = (hash), sl.sl_rsymndx = (rsymndx), \ sl.sl_rsym = (rsym), sl.sl_rtype = (rtype), sl.sl_bind = 0, \ sl.sl_flags = (flags)) /* * After a symbol lookup has been resolved, the runtime linker needs to retain * information regarding the bound definition. An Sresult data structure is * used to provide this information. * * The symbol name (sr_name) may differ from the original referenced symbol if * a symbol capabilities family member has resolved the binding. The defining * object (sr_dmap) indicates the object in which the definition has been found. * The symbol table entry (sr_sym) defines the bound symbol definition. * * Note, a symbol lookup may start with one Sresult buffer, but underlying * routines (for example, those that probe filters) might employ their own * Sresult buffer. If a binding is allowed, the latter buffer may get inherited * by the former. Along with this chain of requests, binding info (binfo) and * not-found information (in_nfavl), may be passed between all the associated * functions. Hence, the binfo and in_nfavl data is not maintained as part of * a Sresult structure. */ struct sresult { const char *sr_name; /* symbol definition name */ Rt_map *sr_dmap; /* defining objects link-map */ Sym *sr_sym; /* symbol table pointer */ }; #define SRESULT_INIT(sr, name) \ (void) (sr.sr_name = (name), sr.sr_dmap = NULL, sr.sr_sym = NULL) /* * Define a system capabilities structure for maintaining the various * capabilities of the system. This structure follows the Objcapset definition * from libld.h, however the system can only have one platform or machine * hardware name, thus this structure is a little simpler. * * Note, the amd64 version of elf_rtbndr assumes that the sc_hw_1 value is at * offset zero and sc_hw_2 is at offset 8. If you are changing this structure * in a way that invalidates this, you need to update that code. */ typedef struct { elfcap_mask_t sc_hw_1; /* CA_SUNW_HW_1 capabilities */ elfcap_mask_t sc_sf_1; /* CA_SUNW_SF_1 capabilities */ elfcap_mask_t sc_hw_2; /* CA_SUNW_HW_2 capabilities */ elfcap_mask_t sc_hw_3; /* CA_SUNW_HW_3 capabilities */ char *sc_plat; /* CA_SUNW_PLAT capability */ size_t sc_platsz; /* and size */ char *sc_mach; /* CA_SUNW_MACH capability */ size_t sc_machsz; /* and size */ } Syscapset; /* * Define a number of .plt lookup outcomes, for use in binding diagnostics. */ typedef enum { PLT_T_NONE = 0, PLT_T_21D, PLT_T_24D, PLT_T_U32, PLT_T_U44, PLT_T_FULL, PLT_T_FAR, PLT_T_NUM /* Must be last */ } Pltbindtype; /* * Prototypes. */ extern ulong_t ld_entry_cnt; /* counter bumped on each entry to */ /* ld.so.1. */ extern Lm_list lml_main; /* main's link map list */ extern Lm_list lml_rtld; /* rtld's link map list */ extern Lm_list *lml_list[]; extern Pltbindtype elf_plt_write(uintptr_t, uintptr_t, void *, uintptr_t, Xword); extern Rt_map *is_so_loaded(Lm_list *, const char *, int *); extern int lookup_sym(Slookup *, Sresult *, uint_t *, int *); extern int rt_dldump(Rt_map *, const char *, int, Addr); #ifdef __cplusplus } #endif #endif /* _RTLD_H */
