1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #ifndef _RTLD_H 28 #define _RTLD_H 29 30 /* 31 * Global include file for the runtime linker. 32 */ 33 #include <time.h> 34 #include <sgs.h> 35 #include <thread.h> 36 #include <synch.h> 37 #include <link.h> 38 #include <sys/avl.h> 39 #include <alist.h> 40 #include <libc_int.h> 41 42 #ifdef _SYSCALL32 43 #include <inttypes.h> 44 #endif 45 46 #ifdef __cplusplus 47 extern "C" { 48 #endif 49 50 51 /* 52 * Linked list of directories or filenames (built from colon separated string). 53 */ 54 typedef struct pnode { 55 const char *p_name; 56 const char *p_oname; 57 size_t p_len; 58 uint_t p_orig; 59 void *p_info; 60 struct pnode *p_next; 61 } Pnode; 62 63 typedef struct rt_map Rt_map; 64 65 /* 66 * A binding descriptor. Establishes the binding relationship between two 67 * objects, the caller (originator) and the dependency (destination). 68 */ 69 typedef struct { 70 Rt_map *b_caller; /* caller (originator) of a binding */ 71 Rt_map *b_depend; /* dependency (destination) of a */ 72 /* binding */ 73 uint_t b_flags; /* relationship of caller to the */ 74 /* dependency */ 75 } Bnd_desc; 76 77 #define BND_NEEDED 0x0001 /* caller NEEDED the dependency */ 78 #define BND_REFER 0x0002 /* caller relocation references the */ 79 /* dependency */ 80 #define BND_FILTER 0x0004 /* pseudo binding to identify filter */ 81 82 /* 83 * Private structure for communication between rtld_db and rtld. 84 * 85 * We must bump the version number when ever an update in one of the 86 * structures/fields that rtld_db reads is updated. This hopefully permits 87 * rtld_db implementations of the future to recognize core files produced on 88 * older systems and deal with these core files accordingly. 89 * 90 * As of version 'RTLD_DB_VERSION <= 2' the following fields were valid for core 91 * file examination (basically the public Link_map): 92 * 93 * ADDR() 94 * NAME() 95 * DYN() 96 * NEXT() 97 * PREV() 98 * 99 * Valid fields for RTLD_DB_VERSION3 100 * 101 * PATHNAME() 102 * PADSTART() 103 * PADIMLEN() 104 * MSIZE() 105 * FLAGS() 106 * FLAGS1() 107 * 108 * Valid fields for RTLD_DB_VERSION4 109 * 110 * TLSMODID() 111 * 112 * Valid fields for RTLD_DB_VERSION5 113 * 114 * Added rtld_flags & FLG_RT_RELOCED to stable flags range 115 * 116 */ 117 #define R_RTLDDB_VERSION1 1 /* base version level - used for core */ 118 /* file examination */ 119 #define R_RTLDDB_VERSION2 2 /* minor revision - not relevant for */ 120 /* core files */ 121 #define R_RTLDDB_VERSION3 3 122 #define R_RTLDDB_VERSION4 4 123 #define R_RTLDDB_VERSION5 5 124 #define R_RTLDDB_VERSION R_RTLDDB_VERSION5 /* current version */ 125 126 typedef struct rtld_db_priv { 127 struct r_debug rtd_rdebug; /* original r_debug structure */ 128 Word rtd_version; /* version no. */ 129 size_t rtd_objpad; /* padding around mmap()ed objects */ 130 List * rtd_dynlmlst; /* pointer to Dynlm_list */ 131 } Rtld_db_priv; 132 133 #ifdef _SYSCALL32 134 typedef struct rtld_db_priv32 { 135 struct r_debug32 rtd_rdebug; /* original r_debug structure */ 136 Elf32_Word rtd_version; /* version no. */ 137 Elf32_Word rtd_objpad; /* padding around mmap()ed objects */ 138 Elf32_Addr rtd_dynlmlst; /* pointer to Dynlm_list */ 139 } Rtld_db_priv32; 140 #endif /* _SYSCALL32 */ 141 142 /* 143 * External function definitions. ld.so.1 must convey information to libc in 144 * regards to threading. libc also provides routines for atexit() and message 145 * localization. libc provides the necessary interfaces via its RTLDINFO 146 * structure and/or later _ld_libc() calls. 147 * 148 * These external functions are maintained for each link-map list, and used 149 * where appropriate. The functions are associated with the object that 150 * provided them, so that should the object be deleted (say, from an alternative 151 * link-map), the functions can be removed. 152 */ 153 typedef struct { 154 Rt_map *lc_lmp; /* function provider */ 155 union { 156 int (*lc_func)(); /* external function pointer */ 157 uintptr_t lc_val; /* external value */ 158 char *lc_ptr; /* external character pointer */ 159 } lc_un; 160 } Lc_desc; 161 162 /* 163 * Link map list definition. Link-maps are used to describe each loaded object. 164 * Lists of these link-maps describe the various namespaces within a process. 165 * The process executable and its dependencies are maintained on the lml_main 166 * list. The runtime linker, and its dependencies are maintained on the 167 * lml_rtld list. Additional lists can be created (see dlmopen()) for such 168 * things as auditors and their dependencies. 169 * 170 * Each link-map list maintains an Alist of one, or more, linked lists of 171 * link-maps. For backward compatibility, the lm_head/lm_tail elements are 172 * initialized to the first linked-list of link-maps: 173 * 174 * Lm_list 175 * ---------- 176 * | lm_tail | ------------------------------------ 177 * | lm_head | -------------------- | 178 * | | | Rt_map | Rt_map 179 * | | | ------ | ------ 180 * | | Alist --> | | |--> | | 181 * | | --------- | | | -- | | 182 * | lm_lists | ----> | | | | | --> | | 183 * | | |---------| | | | | | | 184 * | | | lc_head | -- ------ | ------ 185 * | | | lc_tail | ------------------ 186 * | | |---------| 187 * | lc_head | 188 * | lc_tail | 189 * |---------| 190 * 191 * Multiple link-map lists exist to support the addition of lazy loaded 192 * families, filtee families, and dlopen() families. The intent of these 193 * lists is to insure that a family of objects that are to be loaded are 194 * fully relocatable, and hence usable, before they become part of the main 195 * (al_data[0]) link-map control list. This main link-map control list is 196 * the only list in existence when control is transferred to user code. 197 * 198 * During process initialization, the dynamic executable and its non-lazy 199 * dependencies are maintained on al_data[0]. If a new object is loaded, then 200 * this object is added to the next available control list [1], typically 201 * al_data[1]. Any dependencies of this object that have not already been 202 * loaded are added to the same control list. Once all of the objects on the 203 * new control list have been successfully relocated, the objects are moved from 204 * the new control list to the highest control list to which objects of the new 205 * control list bound to, typically al_data[1] to al_data[0]. 206 * 207 * Each loading scenario can be broken down as follows: 208 * 209 * setup() - only the initial link-map control list is used: 210 * i. create al_data[0] 211 * ii. add new link-map for main on al_data[0] 212 * iii. analyze al_data[0] to add all non-lazy dependencies 213 * iv. relocate al_data[0] dependencies. 214 * 215 * dlopen() - the initiator can only be the initial link-map control list: 216 * i. create al_data[1] from caller al_data[0] 217 * ii. add new link-map for the dlopen'ed object on al_data[1] 218 * iii. analyze al_data[1] to add all non-lazy dependencies 219 * iv. relocate al_data[1] dependencies, and move to al_data[0]. 220 * 221 * filtee and lazy loading processing - the initiator can be any link-map 222 * control list that is being relocated: 223 * i. create al_data[y] from caller al_data[x] 224 * ii. add new link-map for the new object on al_data[y] 225 * iii. analyze al_data[y] to add all non-lazy dependencies 226 * iv. relocate al_data[y] dependencies, and move to al_data[x]. 227 * 228 * This Alist therefore maintains a stack of link-map control lists. The newest 229 * link-map control list can locate symbols within any of the former lists, 230 * however, control is not passed to a former list until the newest lists 231 * processing is complete. Thus, objects can't bind to new objects until they 232 * have been fully analyzed and relocated. 233 * 234 * [1] Note, additional link-map control list creation occurs after the head 235 * link-map object (typically the dynamic executable) has been relocated. This 236 * staging is required to satisfy the binding requirements of copy relocations. 237 * Copy relocations, effectively, transfer the bindings of the copied data 238 * (say _iob in libc.so.1) to the copy location (_iob in the application). 239 * Thus an object that might bind to the original copy data must be redirected 240 * to the copy reference. As the knowledge of a copy relocation having taken 241 * place is only known after relocating the application, link-map control list 242 * additions are suspended until after this relocation has completed. 243 */ 244 typedef struct { 245 Rt_map *lc_head; 246 Rt_map *lc_tail; 247 APlist *lc_now; /* pending promoted bind-now objects */ 248 uint_t lc_flags; 249 } Lm_cntl; 250 251 #define LMC_FLG_ANALYZING 0x01 /* control list is being analyzed */ 252 #define LMC_FLG_RELOCATING 0x02 /* control list is being relocated */ 253 #define LMC_FLG_REANALYZE 0x04 /* repeat analysis (established when */ 254 /* interposers are added */ 255 256 struct lm_list { 257 /* 258 * BEGIN: Exposed to rtld_db - don't move, don't delete 259 */ 260 Rt_map *lm_head; /* linked list pointers to active */ 261 Rt_map *lm_tail; /* link-map list */ 262 APlist *lm_handle; /* not used by rtld_db - but spacing */ 263 /* is required for flags */ 264 Word lm_flags; 265 /* 266 * END: Exposed to rtld_db - don't move, don't delete 267 */ 268 Alist *lm_rti; /* list of RTLDINFO tables */ 269 Audit_list *lm_alp; /* audit list descriptor */ 270 avl_tree_t *lm_fpavl; /* avl tree of objects loaded */ 271 Alist *lm_lists; /* active and pending link-map lists */ 272 char ***lm_environ; /* pointer to environment array */ 273 Word lm_tflags; /* transferable flags */ 274 uint_t lm_obj; /* total number of objs on link-map */ 275 uint_t lm_init; /* new obj since last init processing */ 276 uint_t lm_lazy; /* obj with pending lazy dependencies */ 277 uint_t lm_tls; /* new obj that require TLS */ 278 uint_t lm_lmid; /* unique link-map list identifier, */ 279 char *lm_lmidstr; /* and associated diagnostic string */ 280 APlist *lm_actaudit; /* list of pending audit activity */ 281 Lc_desc lm_lcs[CI_MAX]; /* external libc functions */ 282 }; 283 284 #ifdef _SYSCALL32 285 struct lm_list32 { 286 /* 287 * BEGIN: Exposed to rtld_db - don't move, don't delete 288 */ 289 Elf32_Addr lm_head; 290 Elf32_Addr lm_tail; 291 Elf32_Addr lm_handle; 292 Elf32_Word lm_flags; 293 /* 294 * END: Exposed to rtld_db - don't move, don't delete 295 */ 296 Elf32_Addr lm_rti; 297 Elf32_Addr lm_fpavl; 298 Elf32_Addr lm_lists; 299 Elf32_Addr lm_environ; 300 Elf32_Word lm_tflags; 301 uint_t lm_obj; 302 uint_t lm_init; 303 uint_t lm_lazy; 304 uint_t lm_tls; 305 uint_t lm_lmid; 306 Elf32_Addr lm_lmidstr; 307 Elf32_Addr lm_actaudit; 308 Elf32_Addr lm_lcs[CI_MAX]; 309 }; 310 #endif /* _SYSCALL32 */ 311 312 /* 313 * Possible Link_map list flags (Lm_list.lm_flags) 314 */ 315 /* 316 * BEGIN: Exposed to rtld_db - don't move, don't delete 317 */ 318 #define LML_FLG_BASELM 0x00000001 /* primary link-map */ 319 #define LML_FLG_RTLDLM 0x00000002 /* rtld link-map */ 320 /* 321 * END: Exposed to rtld_db - don't move, don't delete 322 */ 323 #define LML_FLG_NOAUDIT 0x00000004 /* symbol auditing disabled */ 324 #define LML_FLG_PLTREL 0x00000008 /* deferred plt relocation */ 325 /* initialization */ 326 /* (ld.so.1 only) */ 327 #define LML_FLG_HOLDLOCK 0x00000010 /* hold the rtld mutex lock */ 328 #define LML_FLG_ENVIRON 0x00000020 /* environ var initialized */ 329 #define LML_FLG_INTRPOSE 0x00000040 /* interposing objs on list */ 330 #define LML_FLG_LOCAUDIT 0x00000080 /* local auditors exists for */ 331 /* this link-map list */ 332 #define LML_FLG_LOADAVAIL 0x00000100 /* load anything available */ 333 #define LML_FLG_IGNRELERR 0x00000200 /* ignore relocation errors - */ 334 /* internal for crle(1) */ 335 #define LML_FLG_DBNOTIF 0x00000400 /* binding activity going on */ 336 #define LML_FLG_STARTREL 0x00000800 /* relocation started */ 337 #define LML_FLG_ATEXIT 0x00001000 /* atexit processing */ 338 #define LML_FLG_OBJADDED 0x00002000 /* object(s) added */ 339 #define LML_FLG_OBJDELETED 0x00004000 /* object(s) deleted */ 340 #define LML_FLG_OBJREEVAL 0x00008000 /* existing object(s) needs */ 341 /* tsort reevaluation */ 342 #define LML_FLG_NOPENDGLBLAZY 0x00010000 /* no pending, global, lazy */ 343 /* dependencies remain */ 344 #define LML_FLG_INTRPOSETSORT 0x00020000 /* interpose tsorting done */ 345 #define LML_FLG_AUDITNOTIFY 0x00040000 /* audit consistent required */ 346 #define LML_FLG_GROUPSEXIST 0x00080000 /* local groups exist */ 347 348 #define LML_FLG_TRC_LDDSTUB 0x00100000 /* identify lddstub */ 349 #define LML_FLG_TRC_ENABLE 0x00200000 /* tracing enabled (ldd) */ 350 #define LML_FLG_TRC_WARN 0x00400000 /* print warnings for undefs */ 351 #define LML_FLG_TRC_VERBOSE 0x00800000 /* verbose (versioning) trace */ 352 #define LML_FLG_TRC_SEARCH 0x01000000 /* trace search paths */ 353 #define LML_FLG_TRC_UNREF 0x02000000 /* trace unreferenced */ 354 /* dependencies */ 355 #define LML_FLG_TRC_UNUSED 0x04000000 /* trace unused dependencies */ 356 #define LML_FLG_TRC_INIT 0x08000000 /* print .init order */ 357 #define LML_FLG_TRC_NOUNRESWEAK 0x10000000 /* unresolved weak references */ 358 /* are not allowed */ 359 #define LML_FLG_TRC_NOPAREXT 0x20000000 /* unresolved PARENT/EXTERN */ 360 /* references are not */ 361 /* allowed */ 362 #define LML_MSK_TRC 0xfff00000 /* tracing mask */ 363 364 /* 365 * Possible Link_map transferable flags (Lm_list.lm_tflags), i.e., link-map 366 * list flags that can be propagated to any new link-map list created. 367 */ 368 #define LML_TFLG_NOLAZYLD 0x00000001 /* lazy loading disabled */ 369 #define LML_TFLG_NODIRECT 0x00000002 /* direct bindings disabled */ 370 371 #define LML_TFLG_LOADFLTR 0x00000008 /* trigger filtee loading */ 372 373 #define LML_TFLG_AUD_PREINIT 0x00100000 /* preinit (audit) exists */ 374 #define LML_TFLG_AUD_OBJSEARCH 0x00200000 /* objsearch (audit) exists */ 375 #define LML_TFLG_AUD_OBJOPEN 0x00400000 /* objopen (audit) exists */ 376 #define LML_TFLG_AUD_OBJFILTER 0x00800000 /* objfilter (audit) exists */ 377 #define LML_TFLG_AUD_OBJCLOSE 0x01000000 /* objclose (audit) exists */ 378 #define LML_TFLG_AUD_SYMBIND 0x02000000 /* symbind (audit) exists */ 379 #define LML_TFLG_AUD_PLTENTER 0x04000000 /* pltenter (audit) exists */ 380 #define LML_TFLG_AUD_PLTEXIT 0x08000000 /* pltexit (audit) exists */ 381 #define LML_TFLG_AUD_ACTIVITY 0x10000000 /* activity (audit) exists */ 382 383 /* 384 * NOTE: Audit flags have duplicated FLAGS1() values. If more audit flags are 385 * added, update the FLAGS1() reservation FL1_AUD_RS_STR to FL1_AUD_RS_END 386 * defined later. 387 */ 388 #define LML_TFLG_AUD_MASK 0xfff00000 /* audit interfaces mask */ 389 390 /* 391 * Define a Group Handle. 392 * 393 * The capability of ld.so.1 to associate a group of objects, look for symbols 394 * within that group, ensure that groups are isolated from one another (with 395 * regard to relocations), and to unload a group, centers around a handle. This 396 * data structure is tracked from the link-map HANDLE(), and is the structure 397 * returned from dlopen(), and similar object loading capabilities such as 398 * filter/filtee processing. 399 * 400 * A handle keeps track of all the dependencies of the associated object. 401 * These dependencies may be added as objects are lazily loaded. The core 402 * dependencies on the handle are the ldd(1) list of the associated object. 403 * The object assigned the handle, and the parent (or caller) who requested the 404 * handle are also maintained as dependencies on the handle. 405 * 406 * Presently, an object may have two handles, one requested with RTLD_FIRST 407 * and one without. 408 * 409 * A handle may be referenced by any number of parents (callers). A reference 410 * count tracks the number. A dlclose() operation drops the reference count, 411 * and when the count is zero, the handle is used to determine the family of 412 * objects to unload. As bindings may occur to objects on the handle from 413 * other handles, it may not be possible to remove a complete family of 414 * objects or that handle itself. Handles in this state are moved to an orphan 415 * list. A handle on the orphan list is taken off the orphan list if the 416 * associated object is reopened. Otherwise, the handle remains on the orphan 417 * list for the duration of the process. The orphan list is inspected any time 418 * objects are unloaded, to determine if the orphaned objects can also be 419 * unloaded. 420 * 421 * Objects can be dlopened using RTLD_NOW. This attribute requires that all 422 * relocations of the object, and its dependencies are processed immediately, 423 * before return to the caller. Typically, an object is loaded without 424 * RTLD_NOW, and procedure linkage relocations are satisfied when their 425 * associated function is first called. If an object is already loaded, and an 426 * RTLD_NOW request is made, then the object, and its dependencies, most undergo 427 * additional relocation processing. This promotion from lazy binding to 428 * immediate binding is carried out using handles, as the handle defines the 429 * dependencies that must be processed. A temporary handle is created for this 430 * purpose, and is discarded immediately after the promotion operation has been 431 * completed. 432 */ 433 typedef struct { 434 Alist *gh_depends; /* handle dependency list */ 435 Rt_map *gh_ownlmp; /* handle owners link-map */ 436 Lm_list *gh_ownlml; /* handle owners link-map list */ 437 uint_t gh_refcnt; /* handle reference count */ 438 uint_t gh_flags; /* handle flags (GPH_ values) */ 439 } Grp_hdl; 440 441 #define GPH_ZERO 0x0001 /* special handle for dlopen(0) */ 442 #define GPH_LDSO 0x0002 /* special handle for ld.so.1 */ 443 #define GPH_FIRST 0x0004 /* dlsym() can only use originating */ 444 /* dependency */ 445 #define GPH_FILTEE 0x0008 /* handle used to specify a filtee */ 446 #define GPH_INITIAL 0x0010 /* handle is initialized */ 447 #define GPH_NOPENDLAZY 0x0020 /* no pending lazy dependencies */ 448 /* remain for this handle */ 449 450 /* 451 * Define a Group Descriptor. 452 * 453 * Each dependency associated with a group handle is maintained by a group 454 * descriptor. The descriptor defines the associated dependency together with 455 * flags that indicate how the dependency can be used. 456 */ 457 typedef struct { 458 Rt_map * gd_depend; /* dependency */ 459 uint_t gd_flags; /* dependency flags (GPD_ values) */ 460 } Grp_desc; 461 462 #define GPD_DLSYM 0x0001 /* dependency available to dlsym() */ 463 #define GPD_RELOC 0x0002 /* dependency available to satisfy */ 464 /* relocation binding */ 465 #define GPD_ADDEPS 0x0004 /* dependencies of this dependency */ 466 /* should be added to handle */ 467 #define GPD_PARENT 0x0008 /* dependency is a parent */ 468 #define GPD_FILTER 0x0010 /* dependency is our filter */ 469 #define GPD_PROMOTE 0x0020 /* dependency is our RTLD_NOW */ 470 /* promoter */ 471 #define GPD_REMOVE 0x1000 /* descriptor is a candidate for */ 472 /* removal from the group */ 473 474 /* 475 * Define threading structures. For compatibility with libthread (T1_VERSION 1 476 * and TI_VERSION 2) our locking structure is sufficient to hold a mutex or a 477 * readers/writers lock. 478 */ 479 typedef struct { 480 union { 481 mutex_t l_mutex; 482 rwlock_t l_rwlock; 483 } u; 484 } Rt_lock; 485 486 typedef cond_t Rt_cond; 487 488 /* 489 * Define a dynamic section information descriptor. This parallels the entries 490 * in the .dynamic section and holds auxiliary information to implement lazy 491 * loading and filtee processing. 492 */ 493 typedef struct { 494 uint_t di_flags; 495 void *di_info; 496 } Dyninfo; 497 498 #define FLG_DI_STDFLTR 0x00001 /* .dynamic entry for DT_FILTER */ 499 #define FLG_DI_AUXFLTR 0x00002 /* .dynamic entry for DT_AUXILIARY */ 500 #define FLG_DI_SYMFLTR 0x00004 /* .dynamic entry for DT_SYMFILTER */ 501 /* and DT_SYMAUXILIARY */ 502 #define MSK_DI_FILTER 0x0000f /* mask for all filter possibilities */ 503 504 #define FLG_DI_POSFLAG1 0x00010 /* .dynamic entry for DT_POSFLAG_1 */ 505 #define FLG_DI_NEEDED 0x00020 /* .dynamic entry for DT_NEEDED */ 506 #define FLG_DI_LAZY 0x00100 /* lazy needed entry - preceded by */ 507 /* DF_P1_LAZYLOAD (DT_POSFLAG_1) */ 508 #define FLG_DI_GROUP 0x00200 /* group needed entry - preceded by */ 509 /* DF_P1_GROUPPERM (DT_POSFLAG_1) */ 510 511 #define FLG_DI_LDD_DONE 0x01000 /* entry has been processed (ldd) */ 512 #define FLG_DI_LAZYFAIL 0x02000 /* the lazy loading of this entry */ 513 /* failed */ 514 /* 515 * Data structure to track AVL tree of pathnames. This structure provides the 516 * basis of both the "not-found" node tree, and the "full-path" node tree. Both 517 * of these trees persist for the life of a process, although the "not-found" 518 * tree may be moved aside during a dlopen() or dlsym() fall back operation. 519 */ 520 typedef struct { 521 const char *pn_name; /* path name */ 522 avl_node_t pn_avl; /* avl book-keeping (see SGSOFFSETOF) */ 523 uint_t pn_hash; /* path name hash value */ 524 } PathNode; 525 526 /* 527 * Data structure to track AVL tree for full path names of objects that are 528 * loaded into memory. 529 */ 530 typedef struct { 531 PathNode fpn_node; /* path node */ 532 Rt_map *fpn_lmp; /* object link-map */ 533 } FullPathNode; 534 535 /* 536 * Define a mapping structure, which is maintained to describe each mapping 537 * of an object, ie. the text segment, data segment, bss segment, etc. 538 */ 539 typedef struct { 540 caddr_t m_vaddr; /* mapping address */ 541 size_t m_fsize; /* backing file size */ 542 size_t m_msize; /* mapping size */ 543 int m_perm; /* mapping permissions */ 544 } Mmap; 545 546 /* 547 * A given link-map can hold either a supplier or receiver copy 548 * relocation list, but not both. This union is used to overlap 549 * the space used for the two lists. 550 */ 551 typedef union { 552 Alist *rtc_r; /* receiver list (Rel_copy) */ 553 APlist *rtc_s; /* supplier list (Rt_map *) */ 554 } Rt_map_copy; 555 556 557 /* 558 * Link-map definition. 559 */ 560 struct rt_map { 561 /* 562 * BEGIN: Exposed to rtld_db - don't move, don't delete 563 */ 564 Link_map rt_public; /* public data */ 565 char *rt_pathname; /* full pathname of loaded object */ 566 ulong_t rt_padstart; /* start of image (including padding) */ 567 ulong_t rt_padimlen; /* size of image (including padding */ 568 ulong_t rt_msize; /* total memory mapped */ 569 uint_t rt_flags; /* state flags, see FLG below */ 570 uint_t rt_flags1; /* state flags1, see FL1 below */ 571 ulong_t rt_tlsmodid; /* TLS module id */ 572 /* 573 * END: Exposed to rtld_db - don't move, don't delete 574 */ 575 APlist *rt_alias; /* list of linked file names */ 576 APlist *rt_fpnode; /* list of FullpathNode AVL nodes */ 577 void (*rt_init)(); /* address of _init */ 578 void (*rt_fini)(); /* address of _fini */ 579 char *rt_runpath; /* LD_RUN_PATH and its equivalent */ 580 Pnode *rt_runlist; /* Pnode structures */ 581 APlist *rt_depends; /* list of dependencies */ 582 APlist *rt_callers; /* list of callers */ 583 APlist *rt_handles; /* dlopen handles */ 584 APlist *rt_groups; /* groups we're a member of */ 585 ulong_t rt_etext; /* etext address */ 586 struct fct *rt_fct; /* file class table for this object */ 587 Sym *(*rt_symintp)(); /* link map symbol interpreter */ 588 void *rt_priv; /* private data, object type specific */ 589 Lm_list *rt_list; /* link map list we belong to */ 590 uint_t rt_objfltrndx; /* object filtees .dynamic index */ 591 uint_t rt_symsfltrcnt; /* number of standard symbol filtees */ 592 uint_t rt_symafltrcnt; /* number of auxiliary symbol filtees */ 593 int rt_mode; /* usage mode, see RTLD mode flags */ 594 int rt_sortval; /* temporary buffer to traverse graph */ 595 uint_t rt_cycgroup; /* cyclic group */ 596 dev_t rt_stdev; /* device id and inode number for .so */ 597 ino_t rt_stino; /* multiple inclusion checks */ 598 char *rt_origname; /* original pathname of loaded object */ 599 size_t rt_dirsz; /* and its size */ 600 Rt_map_copy rt_copy; /* list of copy relocations */ 601 Audit_desc *rt_auditors; /* audit descriptor array */ 602 Audit_info *rt_audinfo; /* audit information descriptor */ 603 Syminfo *rt_syminfo; /* elf .syminfo section - here */ 604 /* because it is checked in */ 605 /* common code */ 606 Addr *rt_initarray; /* .initarray table */ 607 Addr *rt_finiarray; /* .finiarray table */ 608 Addr *rt_preinitarray; /* .preinitarray table */ 609 Mmap *rt_mmaps; /* array of mapping information */ 610 uint_t rt_mmapcnt; /* and associated number */ 611 uint_t rt_initarraysz; /* size of .initarray table */ 612 uint_t rt_finiarraysz; /* size of .finiarray table */ 613 uint_t rt_preinitarraysz; /* size of .preinitarray table */ 614 Dyninfo *rt_dyninfo; /* .dynamic information descriptors */ 615 uint_t rt_dyninfocnt; /* count of dyninfo entries */ 616 uint_t rt_relacount; /* no. of RELATIVE relocations */ 617 uint_t rt_idx; /* hold index within linkmap list */ 618 uint_t rt_lazy; /* lazy dependencies pending */ 619 Rt_cond *rt_condvar; /* variables */ 620 Xword rt_hwcap; /* hardware capabilities */ 621 Xword rt_sfcap; /* software capabilities */ 622 thread_t rt_threadid; /* thread init/fini synchronization */ 623 uint_t rt_cntl; /* link-map control list we belong to */ 624 uint_t rt_flags2; /* state flags2, see FL2 below */ 625 }; 626 627 628 #ifdef _SYSCALL32 629 /* 630 * Structure to allow 64-bit rtld_db to read 32-bit processes out of procfs. 631 */ 632 typedef union { 633 uint32_t rtc_r; 634 uint32_t rtc_s; 635 } Rt_map_copy32; 636 637 typedef struct rt_map32 { 638 /* 639 * BEGIN: Exposed to rtld_db - don't move, don't delete 640 */ 641 Link_map32 rt_public; 642 uint32_t rt_pathname; 643 uint32_t rt_padstart; 644 uint32_t rt_padimlen; 645 uint32_t rt_msize; 646 uint32_t rt_flags; 647 uint32_t rt_flags1; 648 uint32_t rt_tlsmodid; 649 /* 650 * END: Exposed to rtld_db - don't move, don't delete 651 */ 652 uint32_t rt_alias; 653 uint32_t rt_fpnode; 654 uint32_t rt_init; 655 uint32_t rt_fini; 656 uint32_t rt_runpath; 657 uint32_t rt_runlist; 658 uint32_t rt_depends; 659 uint32_t rt_callers; 660 uint32_t rt_handles; 661 uint32_t rt_groups; 662 uint32_t rt_etext; 663 uint32_t rt_fct; 664 uint32_t rt_symintp; 665 uint32_t rt_priv; 666 uint32_t rt_list; 667 uint32_t rt_objfltrndx; 668 uint32_t rt_symsfltrcnt; 669 uint32_t rt_symafltrcnt; 670 int32_t rt_mode; 671 int32_t rt_sortval; 672 uint32_t rt_cycgroup; 673 uint32_t rt_stdev; 674 uint32_t rt_stino; 675 uint32_t rt_origname; 676 uint32_t rt_dirsz; 677 Rt_map_copy32 rt_copy; 678 uint32_t rt_auditors; 679 uint32_t rt_audinfo; 680 uint32_t rt_syminfo; 681 uint32_t rt_initarray; 682 uint32_t rt_finiarray; 683 uint32_t rt_preinitarray; 684 uint32_t rt_mmaps; 685 uint32_t rt_mmapcnt; 686 uint32_t rt_initarraysz; 687 uint32_t rt_finiarraysz; 688 uint32_t rt_preinitarraysz; 689 uint32_t rt_dyninfo; 690 uint32_t rt_dyninfocnt; 691 uint32_t rt_relacount; 692 uint32_t rt_idx; 693 uint32_t rt_lazy; 694 uint32_t rt_condvar; 695 uint32_t rt_hwcap; 696 uint32_t rt_sfcap; 697 uint32_t rt_threadid; 698 uint32_t rt_cntl; 699 uint32_t rt_flags2; 700 } Rt_map32; 701 702 #endif /* _SYSCALL32 */ 703 704 /* 705 * Link map state flags. 706 */ 707 /* 708 * BEGIN: Exposed to rtld_db - don't move, don't delete 709 */ 710 #define FLG_RT_ISMAIN 0x00000001 /* object represents main executable */ 711 #define FLG_RT_IMGALLOC 0x00000002 /* image is allocated (not mmap'ed) */ 712 /* 713 * Available for r_debug version >= RTLD_DB_VERSION5 714 */ 715 #define FLG_RT_RELOCED 0x00000004 /* object has been relocated */ 716 /* 717 * END: Exposed to rtld_db - don't move, don't delete 718 */ 719 #define FLG_RT_SETGROUP 0x00000008 /* group establishment required */ 720 #define FLG_RT_HWCAP 0x00000010 /* process $HWCAP expansion */ 721 #define FLG_RT_OBJECT 0x00000020 /* object processing (ie. .o's) */ 722 #define FLG_RT_NEWLOAD 0x00000040 /* object is newly loaded */ 723 #define FLG_RT_NODUMP 0x00000080 /* object can't be dldump(3x)'ed */ 724 #define FLG_RT_DELETE 0x00000100 /* object can be deleted */ 725 #define FLG_RT_ANALYZED 0x00000200 /* object has been analyzed */ 726 #define FLG_RT_INITDONE 0x00000400 /* objects .init has been completed */ 727 #define FLG_RT_TRANS 0x00000800 /* object is acting as a translator */ 728 #define FLG_RT_FIXED 0x00001000 /* image location is fixed */ 729 #define FLG_RT_PRELOAD 0x00002000 /* object was preloaded */ 730 #define FLG_RT_ALTER 0x00004000 /* alternative object used */ 731 #define FLG_RT_LOADFLTR 0x00008000 /* trigger filtee loading */ 732 #define FLG_RT_AUDIT 0x00010000 /* object is an auditor */ 733 #define FLG_RT_MODESET 0x00020000 /* MODE() has been initialized */ 734 #define FLG_RT_ANALZING 0x00040000 /* object is being analyzed */ 735 #define FLG_RT_INITFRST 0x00080000 /* execute .init first */ 736 #define FLG_RT_NOOPEN 0x00100000 /* dlopen() not allowed */ 737 #define FLG_RT_FINICLCT 0x00200000 /* fini has been collected (tsort) */ 738 #define FLG_RT_INITCALL 0x00400000 /* objects .init has been called */ 739 #define FLG_RT_OBJINTPO 0x00800000 /* object is a global interposer */ 740 #define FLG_RT_SYMINTPO 0x01000000 /* object contains symbol interposer */ 741 #define MSK_RT_INTPOSE 0x01800000 /* mask for all interposer */ 742 /* possibilities */ 743 #define FLG_RT_MOVE 0x02000000 /* object needs move operation */ 744 #define FLG_RT_TMPLIST 0x04000000 /* object is part of a temporary list */ 745 #define FLG_RT_REGSYMS 0x08000000 /* object has DT_REGISTER entries */ 746 #define FLG_RT_INITCLCT 0x10000000 /* init has been collected (tsort) */ 747 #define FLG_RT_HANDLE 0x20000000 /* generate a handle for this object */ 748 #define FLG_RT_RELOCING 0x40000000 /* object is being relocated */ 749 750 #define FL1_RT_COPYTOOK 0x00000001 /* copy relocation taken */ 751 #define FL1_RT_RELATIVE 0x00000002 /* relative path expansion required */ 752 #define FL1_RT_CONFSET 0x00000004 /* object was loaded by crle(1) */ 753 #define FL1_RT_NODEFLIB 0x00000008 /* ignore default library search */ 754 #define FL1_RT_ENDFILTE 0x00000010 /* filtee terminates filters search */ 755 #define FL1_RT_DISPREL 0x00000020 /* object has *disp* relocation */ 756 #define FL1_RT_TEXTREL 0x00000040 /* DT_TEXTREL set in object */ 757 #define FL1_RT_INITWAIT 0x00000080 /* threads are waiting on .init */ 758 #define FL1_RT_LDDSTUB 0x00000100 /* identify lddstub */ 759 #define FL1_RT_NOINIFIN 0x00000200 /* no .init or .fini exists */ 760 #define FL1_RT_USED 0x00000400 /* symbol referenced from this object */ 761 #define FL1_RT_SYMBOLIC 0x00000800 /* DF_SYMBOLIC was set - use */ 762 /* symbolic sym resolution */ 763 #define FL1_RT_OBJSFLTR 0x00001000 /* object is acting as a standard */ 764 #define FL1_RT_OBJAFLTR 0x00002000 /* or auxiliary filter */ 765 #define FL1_RT_SYMSFLTR 0x00004000 /* symbol is acting as a standard */ 766 #define FL1_RT_SYMAFLTR 0x00008000 /* or auxiliary filter */ 767 #define MSK_RT_FILTER 0x0000f000 /* mask for all filter possibilities */ 768 769 #define FL1_RT_TLSADD 0x00010000 /* objects TLS has been registered */ 770 #define FL1_RT_TLSSTAT 0x00020000 /* object requires static TLS */ 771 #define FL1_RT_DIRECT 0x00040000 /* object has DIRECT bindings enabled */ 772 #define FL1_RT_GLOBAUD 0x00080000 /* establish global auditing */ 773 774 /* 775 * The following range of bits are reserved to hold LML_TFLG_AUD_ values 776 * (although the definitions themselves aren't used anywhere). 777 */ 778 #define FL1_AUD_RS_STR 0x00100000 /* RESERVATION start for AU flags */ 779 #define FL1_AUD_RS_END 0x80000000 /* RESERVATION end for AU flags */ 780 781 #define FL2_RT_DTFLAGS 0x00000001 /* DT_FLAGS element exists */ 782 783 /* 784 * Flags for the tls_modactivity() routine 785 */ 786 #define TM_FLG_MODADD 0x01 /* call tls_modadd() interface */ 787 #define TM_FLG_MODREM 0x02 /* call tls_modrem() interface */ 788 789 /* 790 * Macros for getting to link_map data. 791 */ 792 #define ADDR(X) ((X)->rt_public.l_addr) 793 #define NAME(X) ((X)->rt_public.l_name) 794 #define DYN(X) ((X)->rt_public.l_ld) 795 #define NEXT(X) ((X)->rt_public.l_next) 796 #define PREV(X) ((X)->rt_public.l_prev) 797 #define REFNAME(X) ((X)->rt_public.l_refname) 798 799 /* 800 * Macros for getting to linker private data. 801 */ 802 #define PATHNAME(X) ((X)->rt_pathname) 803 #define PADSTART(X) ((X)->rt_padstart) 804 #define PADIMLEN(X) ((X)->rt_padimlen) 805 #define MSIZE(X) ((X)->rt_msize) 806 #define FLAGS(X) ((X)->rt_flags) 807 #define FLAGS1(X) ((X)->rt_flags1) 808 #define FLAGS2(X) ((X)->rt_flags2) 809 #define TLSMODID(X) ((X)->rt_tlsmodid) 810 811 #define ALIAS(X) ((X)->rt_alias) 812 #define FPNODE(X) ((X)->rt_fpnode) 813 #define INIT(X) ((X)->rt_init) 814 #define FINI(X) ((X)->rt_fini) 815 #define RPATH(X) ((X)->rt_runpath) 816 #define RLIST(X) ((X)->rt_runlist) 817 #define DEPENDS(X) ((X)->rt_depends) 818 #define CALLERS(X) ((X)->rt_callers) 819 #define HANDLES(X) ((X)->rt_handles) 820 #define GROUPS(X) ((X)->rt_groups) 821 #define ETEXT(X) ((X)->rt_etext) 822 #define FCT(X) ((X)->rt_fct) 823 #define SYMINTP(X) ((X)->rt_symintp) 824 #define LIST(X) ((X)->rt_list) 825 #define OBJFLTRNDX(X) ((X)->rt_objfltrndx) 826 #define SYMSFLTRCNT(X) ((X)->rt_symsfltrcnt) 827 #define SYMAFLTRCNT(X) ((X)->rt_symafltrcnt) 828 #define MODE(X) ((X)->rt_mode) 829 #define SORTVAL(X) ((X)->rt_sortval) 830 #define CYCGROUP(X) ((X)->rt_cycgroup) 831 #define STDEV(X) ((X)->rt_stdev) 832 #define STINO(X) ((X)->rt_stino) 833 #define ORIGNAME(X) ((X)->rt_origname) 834 #define DIRSZ(X) ((X)->rt_dirsz) 835 #define COPY_R(X) ((X)->rt_copy.rtc_r) 836 #define COPY_S(X) ((X)->rt_copy.rtc_s) 837 #define AUDITORS(X) ((X)->rt_auditors) 838 #define AUDINFO(X) ((X)->rt_audinfo) 839 #define SYMINFO(X) ((X)->rt_syminfo) 840 #define INITARRAY(X) ((X)->rt_initarray) 841 #define FINIARRAY(X) ((X)->rt_finiarray) 842 #define PREINITARRAY(X) ((X)->rt_preinitarray) 843 #define MMAPS(X) ((X)->rt_mmaps) 844 #define MMAPCNT(X) ((X)->rt_mmapcnt) 845 #define INITARRAYSZ(X) ((X)->rt_initarraysz) 846 #define FINIARRAYSZ(X) ((X)->rt_finiarraysz) 847 #define PREINITARRAYSZ(X) ((X)->rt_preinitarraysz) 848 #define DYNINFO(X) ((X)->rt_dyninfo) 849 #define DYNINFOCNT(X) ((X)->rt_dyninfocnt) 850 #define RELACOUNT(X) ((X)->rt_relacount) 851 #define IDX(X) ((X)->rt_idx) 852 #define LAZY(X) ((X)->rt_lazy) 853 #define CONDVAR(X) ((X)->rt_condvar) 854 #define CNTL(X) ((X)->rt_cntl) 855 #define HWCAP(X) ((X)->rt_hwcap) 856 #define SFCAP(X) ((X)->rt_sfcap) 857 #define THREADID(X) ((X)->rt_threadid) 858 859 /* 860 * Flags for tsorting. 861 */ 862 #define RT_SORT_FWD 0x01 /* topological sort (.fini) */ 863 #define RT_SORT_REV 0x02 /* reverse topological sort (.init) */ 864 #define RT_SORT_DELETE 0x10 /* process FLG_RT_DELNEED objects */ 865 /* only (called via dlclose()) */ 866 #define RT_SORT_INTPOSE 0x20 /* process interposer objects */ 867 868 /* 869 * Flags for lookup_sym (and hence find_sym) routines. 870 */ 871 #define LKUP_DEFT 0x0000 /* simple lookup request */ 872 #define LKUP_SPEC 0x0001 /* special ELF lookup (allows address */ 873 /* resolutions to plt[] entries) */ 874 #define LKUP_LDOT 0x0002 /* indicates the original A_OUT */ 875 /* symbol had a leading `.' */ 876 #define LKUP_FIRST 0x0004 /* lookup symbol in first link map */ 877 /* only */ 878 #define LKUP_COPY 0x0008 /* lookup symbol for a COPY reloc, do */ 879 /* not bind to symbol at head */ 880 #define LKUP_STDRELOC 0x0010 /* lookup originates from a standard */ 881 /* relocation (elf_reloc()) */ 882 #define LKUP_SELF 0x0020 /* lookup symbol in ourself - undef */ 883 /* is valid */ 884 #define LKUP_WEAK 0x0040 /* relocation reference is weak */ 885 #define LKUP_NEXT 0x0080 /* request originates from RTLD_NEXT */ 886 #define LKUP_NODESCENT 0x0100 /* don't descend through dependencies */ 887 #define LKUP_NOFALLBACK 0x0200 /* don't fall back to loading */ 888 /* pending lazy dependencies */ 889 #define LKUP_DIRECT 0x0400 /* direct binding request */ 890 #define LKUP_SYMNDX 0x0800 /* establish symbol index */ 891 #define LKUP_SINGLETON 0x1000 /* search for a singleton symbol */ 892 #define LKUP_STANDARD 0x2000 /* standard lookup - originated from */ 893 /* head link-map element */ 894 #define LKUP_WORLD 0x4000 /* ensure world lookup */ 895 896 /* 897 * For the runtime linker to perform a symbol search, a number of data items 898 * related to the search are required. An Slookup data structure is used to 899 * convey this data to lookup_sym(), and in special cases, to other core 900 * routines that provide the implementation details for lookup_sym() 901 * 902 * The symbol name (sl_name), the caller (sl_cmap), and the link-map from which 903 * to start the search (sl_imap) are fundamental to the symbol search. The 904 * initial search link-map might get modified by the core routines that provide 905 * the implementation details for lookup_sym(). This modification accommodates 906 * requirements such as processing a handle, direct binding and interposition. 907 * The association between the caller and the potential destination also 908 * determines whether the destination is a candidate to search. 909 * 910 * The lookup identifier (sl_id) is used to identify a runtime linker operation. 911 * Within this operation, any lazy loads that fail are not re-examined. This 912 * technique keeps the overhead of processing a failed lazy load to a minimum. 913 * 914 * Symbol searches that originate from a relocation record are accompanied by 915 * the relocation index (sl_rsymndx), the symbol reference (sl_rsym) and 916 * possibly the relocation type (sl_rtype). This data provides for determining 917 * lazy loading, direct binding, and special symbol processing requirements 918 * such as copy relocations and singleton lookup. 919 * 920 * The symbols hash value is computed by lookup_sym, and propagated throughout 921 * the search engine. Note, occasionally the Slookup data is passed to a core 922 * routine that provides the implementation details for lookup_sym(), ie. 923 * elf_find_sym(), in which case the caller must initialize the hash value. 924 * 925 * The symbols binding information is established by lookup_sym() when the 926 * symbols relocation type is supplied. Weak bindings allow relocations to 927 * be set to zero should a symbol lookup fail. 928 * 929 * The flags allow the caller to control aspects of the search, including the 930 * interpretation of copy relocations, etc. Note, a number of flag settings 931 * are established in lookup_sym() from attributes of the symbol reference. 932 */ 933 typedef struct { 934 const char *sl_name; /* symbol name */ 935 Rt_map *sl_cmap; /* callers link-map */ 936 Rt_map *sl_imap; /* initial link-map to search */ 937 ulong_t sl_id; /* identifier for this lookup */ 938 ulong_t sl_hash; /* symbol hash value */ 939 ulong_t sl_rsymndx; /* referencing reloc symndx */ 940 Sym *sl_rsym; /* referencing symbol */ 941 uchar_t sl_rtype; /* relocation type associate with */ 942 /* symbol */ 943 uchar_t sl_bind; /* symbols binding (returned) */ 944 uint_t sl_flags; /* lookup flags */ 945 } Slookup; 946 947 #define SLOOKUP_INIT(sl, name, cmap, imap, id, hash, rsymndx, rsym, rtype, \ 948 flags) \ 949 (void) (sl.sl_name = (name), sl.sl_cmap = (cmap), sl.sl_imap = (imap), \ 950 sl.sl_id = (id), sl.sl_hash = (hash), sl.sl_rsymndx = (rsymndx), \ 951 sl.sl_rsym = (rsym), sl.sl_rtype = (rtype), sl.sl_bind = 0, \ 952 sl.sl_flags = (flags)) 953 954 /* 955 * Define a number of .plt lookup outcomes, for use in binding diagnostics. 956 */ 957 typedef enum { 958 PLT_T_NONE = 0, 959 PLT_T_21D, 960 PLT_T_24D, 961 PLT_T_U32, 962 PLT_T_U44, 963 PLT_T_FULL, 964 PLT_T_FAR, 965 PLT_T_NUM /* Must be last */ 966 } Pltbindtype; 967 968 /* 969 * Prototypes. 970 */ 971 extern ulong_t ld_entry_cnt; /* counter bumped on each entry to */ 972 /* ld.so.1. */ 973 extern Lm_list lml_main; /* main's link map list */ 974 extern Lm_list lml_rtld; /* rtld's link map list */ 975 extern Lm_list *lml_list[]; 976 977 extern Pltbindtype elf_plt_write(uintptr_t, uintptr_t, void *, uintptr_t, 978 Xword); 979 extern Rt_map *is_so_loaded(Lm_list *, const char *, int *); 980 extern Sym *lookup_sym(Slookup *, Rt_map **, uint_t *, int *); 981 extern int rt_dldump(Rt_map *, const char *, int, Addr); 982 983 #ifdef __cplusplus 984 } 985 #endif 986 987 #endif /* _RTLD_H */ 988