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 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 #ifndef _RTLD_H 27 #define _RTLD_H 28 29 /* 30 * Global include file for the runtime linker. 31 */ 32 #include <sys/mman.h> 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 * We use rtld_ino_t instead of ino_t so that we can get 52 * access to large inode values from 32-bit code. 53 */ 54 #ifdef _LP64 55 typedef ino_t rtld_ino_t; 56 #else 57 typedef ino64_t rtld_ino_t; 58 #endif 59 60 typedef struct rt_map Rt_map; 61 typedef struct slookup Slookup; 62 63 /* 64 * A binding descriptor. Establishes the binding relationship between two 65 * objects, the caller (originator) and the dependency (destination). 66 */ 67 typedef struct { 68 Rt_map *b_caller; /* caller (originator) of a binding */ 69 Rt_map *b_depend; /* dependency (destination) of a */ 70 /* binding */ 71 uint_t b_flags; /* relationship of caller to the */ 72 /* dependency */ 73 } Bnd_desc; 74 75 #define BND_NEEDED 0x0001 /* caller NEEDED the dependency */ 76 #define BND_REFER 0x0002 /* caller relocation references the */ 77 /* dependency */ 78 #define BND_FILTER 0x0004 /* pseudo binding to identify filter */ 79 80 /* 81 * Private structure for communication between rtld_db and rtld. 82 * 83 * We must bump the version number when ever an update in one of the 84 * structures/fields that rtld_db reads is updated. This hopefully permits 85 * rtld_db implementations of the future to recognize core files produced on 86 * older systems and deal with these core files accordingly. 87 * 88 * As of version 'R_RTLDDB_VERSION <= 2' the following fields were valid for 89 * core file examination (basically the public Link_map): 90 * 91 * ADDR() 92 * NAME() 93 * DYN() 94 * NEXT() 95 * PREV() 96 * 97 * Valid fields for R_RTLDDB_VERSION3 98 * 99 * PATHNAME() 100 * PADSTART() 101 * PADIMLEN() 102 * MSIZE() 103 * FLAGS() 104 * FLAGS1() 105 * 106 * Valid fields for R_RTLDDB_VERSION4 107 * 108 * TLSMODID() 109 * 110 * Valid fields for R_RTLDDB_VERSION5 111 * 112 * Added rtld_flags & FLG_RT_RELOCED to stable flags range 113 * 114 */ 115 #define R_RTLDDB_VERSION1 1 /* base version level - used for core */ 116 /* file examination */ 117 #define R_RTLDDB_VERSION2 2 /* minor revision - not relevant for */ 118 /* core files */ 119 #define R_RTLDDB_VERSION3 3 120 #define R_RTLDDB_VERSION4 4 121 #define R_RTLDDB_VERSION5 5 122 #define R_RTLDDB_VERSION R_RTLDDB_VERSION5 /* current version */ 123 124 typedef struct rtld_db_priv { 125 struct r_debug rtd_rdebug; /* original r_debug structure */ 126 Word rtd_version; /* version no. */ 127 size_t rtd_objpad; /* padding around mmap()ed objects */ 128 APlist **rtd_dynlmlst; /* pointer to dynlm_list pointer */ 129 } Rtld_db_priv; 130 131 #ifdef _SYSCALL32 132 typedef struct rtld_db_priv32 { 133 struct r_debug32 rtd_rdebug; /* original r_debug structure */ 134 Elf32_Word rtd_version; /* version no. */ 135 Elf32_Word rtd_objpad; /* padding around mmap()ed objects */ 136 Elf32_Addr rtd_dynlmlst; /* pointer to dynlm_list */ 137 } Rtld_db_priv32; 138 #endif /* _SYSCALL32 */ 139 140 /* 141 * External function definitions. ld.so.1 must convey information to libc in 142 * regards to threading. libc also provides routines for atexit() and message 143 * localization. libc provides the necessary interfaces via its RTLDINFO 144 * structure and/or later _ld_libc() calls. 145 * 146 * These external functions are maintained for each link-map list, and used 147 * where appropriate. The functions are associated with the object that 148 * provided them, so that should the object be deleted (say, from an alternative 149 * link-map), the functions can be removed. 150 */ 151 typedef struct { 152 Rt_map *lc_lmp; /* function provider */ 153 union { 154 int (*lc_func)(); /* external function pointer */ 155 uintptr_t lc_val; /* external value */ 156 char *lc_ptr; /* external character pointer */ 157 } lc_un; 158 } Lc_desc; 159 160 /* 161 * Link map list definition. Link-maps are used to describe each loaded object. 162 * Lists of these link-maps describe the various namespaces within a process. 163 * The process executable and its dependencies are maintained on the lml_main 164 * list. The runtime linker, and its dependencies are maintained on the 165 * lml_rtld list. Additional lists can be created (see dlmopen()) for such 166 * things as auditors and their dependencies. 167 * 168 * Each link-map list maintains an Alist of one, or more, linked lists of 169 * link-maps. For backward compatibility, the lm_head/lm_tail elements are 170 * initialized to the first linked-list of link-maps: 171 * 172 * Lm_list 173 * ---------- 174 * | lm_tail | ------------------------------------ 175 * | lm_head | -------------------- | 176 * | | | Rt_map | Rt_map 177 * | | | ------ | ------ 178 * | | Alist --> | | |--> | | 179 * | | --------- | | | -- | | 180 * | lm_lists | ----> | | | | | --> | | 181 * | | |---------| | | | | | | 182 * | | | lc_head | -- ------ | ------ 183 * | | | lc_tail | ------------------ 184 * | | |---------| 185 * | lc_head | 186 * | lc_tail | 187 * |---------| 188 * 189 * Multiple link-map lists exist to support the addition of lazy loaded 190 * families, filtee families, and dlopen() families. The intent of these 191 * lists is to insure that a family of objects that are to be loaded are 192 * fully relocatable, and hence usable, before they become part of the main 193 * (al_data[0]) link-map control list. This main link-map control list is 194 * the only list in existence when control is transferred to user code. 195 * 196 * During process initialization, the dynamic executable and its non-lazy 197 * dependencies are maintained on al_data[0]. If a new object is loaded, then 198 * this object is added to the next available control list [1], typically 199 * al_data[1]. Any dependencies of this object that have not already been 200 * loaded are added to the same control list. Once all of the objects on the 201 * new control list have been successfully relocated, the objects are moved from 202 * the new control list to the highest control list to which objects of the new 203 * control list bound to, typically al_data[1] to al_data[0]. 204 * 205 * Each loading scenario can be broken down as follows: 206 * 207 * setup() - only the initial link-map control list is used: 208 * i. create al_data[0] 209 * ii. add new link-map for main on al_data[0] 210 * iii. analyze al_data[0] to add all non-lazy dependencies 211 * iv. relocate al_data[0] dependencies. 212 * 213 * dlopen() - the initiator can only be the initial link-map control list: 214 * i. create al_data[1] from caller al_data[0] 215 * ii. add new link-map for the dlopen'ed object on al_data[1] 216 * iii. analyze al_data[1] to add all non-lazy dependencies 217 * iv. relocate al_data[1] dependencies, and move to al_data[0]. 218 * 219 * filtee and lazy loading processing - the initiator can be any link-map 220 * control list that is being relocated: 221 * i. create al_data[y] from caller al_data[x] 222 * ii. add new link-map for the new object on al_data[y] 223 * iii. analyze al_data[y] to add all non-lazy dependencies 224 * iv. relocate al_data[y] dependencies, and move to al_data[x]. 225 * 226 * This Alist therefore maintains a stack of link-map control lists. The newest 227 * link-map control list can locate symbols within any of the former lists, 228 * however, control is not passed to a former list until the newest lists 229 * processing is complete. Thus, objects can't bind to new objects until they 230 * have been fully analyzed and relocated. 231 * 232 * [1] Note, additional link-map control list creation occurs after the head 233 * link-map object (typically the dynamic executable) has been relocated. This 234 * staging is required to satisfy the binding requirements of copy relocations. 235 * Copy relocations, effectively, transfer the bindings of the copied data 236 * (say _iob in libc.so.1) to the copy location (_iob in the application). 237 * Thus an object that might bind to the original copy data must be redirected 238 * to the copy reference. As the knowledge of a copy relocation having taken 239 * place is only known after relocating the application, link-map control list 240 * additions are suspended until after this relocation has completed. 241 */ 242 typedef struct { 243 Rt_map *lc_head; 244 Rt_map *lc_tail; 245 APlist *lc_now; /* pending promoted bind-now objects */ 246 uint_t lc_flags; 247 } Lm_cntl; 248 249 #define LMC_FLG_ANALYZING 0x01 /* control list is being analyzed */ 250 #define LMC_FLG_RELOCATING 0x02 /* control list is being relocated */ 251 #define LMC_FLG_REANALYZE 0x04 /* repeat analysis (established when */ 252 /* interposers are added */ 253 254 struct lm_list { 255 /* 256 * BEGIN: Exposed to rtld_db - don't move, don't delete 257 */ 258 Rt_map *lm_head; /* linked list pointers to active */ 259 Rt_map *lm_tail; /* link-map list */ 260 APlist *lm_handle; /* not used by rtld_db - but spacing */ 261 /* is required for flags */ 262 Word lm_flags; 263 /* 264 * END: Exposed to rtld_db - don't move, don't delete 265 */ 266 Alist *lm_rti; /* list of RTLDINFO tables */ 267 Audit_list *lm_alp; /* audit list descriptor */ 268 avl_tree_t *lm_fpavl; /* avl tree of objects loaded */ 269 Alist *lm_lists; /* active and pending link-map lists */ 270 char ***lm_environ; /* pointer to environment array */ 271 Word lm_tflags; /* transferable flags */ 272 uint_t lm_obj; /* total number of objs on link-map */ 273 uint_t lm_init; /* new obj since last init processing */ 274 uint_t lm_lazy; /* obj with pending lazy dependencies */ 275 uint_t lm_tls; /* new obj that require TLS */ 276 uint_t lm_lmid; /* unique link-map list identifier, */ 277 char *lm_lmidstr; /* and associated diagnostic string */ 278 APlist *lm_actaudit; /* list of pending audit activity */ 279 Lc_desc lm_lcs[CI_MAX]; /* external libc functions */ 280 }; 281 282 #ifdef _SYSCALL32 283 struct lm_list32 { 284 /* 285 * BEGIN: Exposed to rtld_db - don't move, don't delete 286 */ 287 Elf32_Addr lm_head; 288 Elf32_Addr lm_tail; 289 Elf32_Addr lm_handle; 290 Elf32_Word lm_flags; 291 /* 292 * END: Exposed to rtld_db - don't move, don't delete 293 */ 294 Elf32_Addr lm_rti; 295 Elf32_Addr lm_fpavl; 296 Elf32_Addr lm_lists; 297 Elf32_Addr lm_environ; 298 Elf32_Word lm_tflags; 299 uint_t lm_obj; 300 uint_t lm_init; 301 uint_t lm_lazy; 302 uint_t lm_tls; 303 uint_t lm_lmid; 304 Elf32_Addr lm_lmidstr; 305 Elf32_Addr lm_actaudit; 306 Elf32_Addr lm_lcs[CI_MAX]; 307 }; 308 #endif /* _SYSCALL32 */ 309 310 /* 311 * Possible Link_map list flags (Lm_list.lm_flags) 312 */ 313 /* 314 * BEGIN: Exposed to rtld_db - don't move, don't delete 315 */ 316 #define LML_FLG_BASELM 0x00000001 /* primary link-map */ 317 #define LML_FLG_RTLDLM 0x00000002 /* rtld link-map */ 318 /* 319 * END: Exposed to rtld_db - don't move, don't delete 320 */ 321 #define LML_FLG_NOAUDIT 0x00000004 /* symbol auditing disabled */ 322 #define LML_FLG_PLTREL 0x00000008 /* deferred plt relocation */ 323 /* initialization */ 324 /* (ld.so.1 only) */ 325 #define LML_FLG_HOLDLOCK 0x00000010 /* hold the rtld mutex lock */ 326 #define LML_FLG_ENVIRON 0x00000020 /* environ var initialized */ 327 #define LML_FLG_INTRPOSE 0x00000040 /* interposing objs on list */ 328 #define LML_FLG_LOCAUDIT 0x00000080 /* local auditors exists for */ 329 /* this link-map list */ 330 #define LML_FLG_LOADAVAIL 0x00000100 /* load anything available */ 331 #define LML_FLG_IGNRELERR 0x00000200 /* ignore relocation errors - */ 332 /* internal for crle(1) */ 333 #define LML_FLG_DBNOTIF 0x00000400 /* binding activity going on */ 334 #define LML_FLG_STARTREL 0x00000800 /* relocation started */ 335 #define LML_FLG_ATEXIT 0x00001000 /* atexit processing */ 336 #define LML_FLG_OBJADDED 0x00002000 /* object(s) added */ 337 #define LML_FLG_OBJDELETED 0x00004000 /* object(s) deleted */ 338 #define LML_FLG_OBJREEVAL 0x00008000 /* existing object(s) needs */ 339 /* tsort reevaluation */ 340 #define LML_FLG_NOPENDGLBLAZY 0x00010000 /* no pending, global, lazy */ 341 /* dependencies remain */ 342 #define LML_FLG_INTRPOSETSORT 0x00020000 /* interpose tsorting done */ 343 #define LML_FLG_AUDITNOTIFY 0x00040000 /* audit consistent required */ 344 #define LML_FLG_GROUPSEXIST 0x00080000 /* local groups exist */ 345 346 #define LML_FLG_TRC_LDDSTUB 0x00100000 /* identify lddstub */ 347 #define LML_FLG_TRC_ENABLE 0x00200000 /* tracing enabled (ldd) */ 348 #define LML_FLG_TRC_WARN 0x00400000 /* print warnings for undefs */ 349 #define LML_FLG_TRC_VERBOSE 0x00800000 /* verbose (versioning) trace */ 350 #define LML_FLG_TRC_SEARCH 0x01000000 /* trace search paths */ 351 #define LML_FLG_TRC_UNREF 0x02000000 /* trace unreferenced */ 352 /* dependencies */ 353 #define LML_FLG_TRC_UNUSED 0x04000000 /* trace unused dependencies */ 354 #define LML_FLG_TRC_INIT 0x08000000 /* print .init order */ 355 #define LML_FLG_TRC_NOUNRESWEAK 0x10000000 /* unresolved weak references */ 356 /* are not allowed */ 357 #define LML_FLG_TRC_NOPAREXT 0x20000000 /* unresolved PARENT/EXTERN */ 358 /* references are not */ 359 /* allowed */ 360 #define LML_MSK_TRC 0xfff00000 /* tracing mask */ 361 362 /* 363 * Possible Link_map transferable flags (Lm_list.lm_tflags), i.e., link-map 364 * list flags that can be propagated to any new link-map list created. 365 */ 366 #define LML_TFLG_NOLAZYLD 0x00000001 /* lazy loading disabled */ 367 #define LML_TFLG_NODIRECT 0x00000002 /* direct bindings disabled */ 368 369 #define LML_TFLG_LOADFLTR 0x00000008 /* trigger filtee loading */ 370 371 #define LML_TFLG_AUD_PREINIT 0x00001000 /* preinit (audit) exists */ 372 #define LML_TFLG_AUD_OBJSEARCH 0x00002000 /* objsearch (audit) exists */ 373 #define LML_TFLG_AUD_OBJOPEN 0x00004000 /* objopen (audit) exists */ 374 #define LML_TFLG_AUD_OBJFILTER 0x00008000 /* objfilter (audit) exists */ 375 #define LML_TFLG_AUD_OBJCLOSE 0x00010000 /* objclose (audit) exists */ 376 #define LML_TFLG_AUD_SYMBIND 0x00020000 /* symbind (audit) exists */ 377 #define LML_TFLG_AUD_PLTENTER 0x00040000 /* pltenter (audit) exists */ 378 #define LML_TFLG_AUD_PLTEXIT 0x00080000 /* pltexit (audit) exists */ 379 #define LML_TFLG_AUD_ACTIVITY 0x00100000 /* activity (audit) exists */ 380 381 /* 382 * NOTE: Each auditing module establishes a set of audit flags, AFLAGS(), that 383 * define the auditing interfaces the module offers. These auditing flags are 384 * the LML_TFLG_AUD_ flags defined above. Global auditors result in setting 385 * the lm_tflags too. Local auditors only use the AFLAGS(). All tests for 386 * auditing inspect the lm_tflags and AFLAGS() for a specific auditing 387 * interface, and thus use the same flag to test for both types of auditors. 388 */ 389 #define LML_TFLG_AUD_MASK 0x0ffff000 /* audit interfaces mask */ 390 391 /* 392 * Define a Group Handle. 393 * 394 * The capability of ld.so.1 to associate a group of objects, look for symbols 395 * within that group, ensure that groups are isolated from one another (with 396 * regard to relocations), and to unload a group, centers around a handle. This 397 * data structure is tracked from the link-map HANDLE(), and is the structure 398 * returned from dlopen(), and similar object loading capabilities such as 399 * filter/filtee processing. 400 * 401 * A handle keeps track of all the dependencies of the associated object. 402 * These dependencies may be added as objects are lazily loaded. The core 403 * dependencies on the handle are the ldd(1) list of the associated object. 404 * The object assigned the handle, and the parent (or caller) who requested the 405 * handle are also maintained as dependencies on the handle. 406 * 407 * Presently, an object may have two handles, one requested with RTLD_FIRST 408 * and one without. 409 * 410 * A handle may be referenced by any number of parents (callers). A reference 411 * count tracks the number. A dlclose() operation drops the reference count, 412 * and when the count is zero, the handle is used to determine the family of 413 * objects to unload. As bindings may occur to objects on the handle from 414 * other handles, it may not be possible to remove a complete family of 415 * objects or that handle itself. Handles in this state are moved to an orphan 416 * list. A handle on the orphan list is taken off the orphan list if the 417 * associated object is reopened. Otherwise, the handle remains on the orphan 418 * list for the duration of the process. The orphan list is inspected any time 419 * objects are unloaded, to determine if the orphaned objects can also be 420 * unloaded. 421 * 422 * Objects can be dlopened using RTLD_NOW. This attribute requires that all 423 * relocations of the object, and its dependencies are processed immediately, 424 * before return to the caller. Typically, an object is loaded without 425 * RTLD_NOW, and procedure linkage relocations are satisfied when their 426 * associated function is first called. If an object is already loaded, and an 427 * RTLD_NOW request is made, then the object, and its dependencies, most undergo 428 * additional relocation processing. This promotion from lazy binding to 429 * immediate binding is carried out using handles, as the handle defines the 430 * dependencies that must be processed. A temporary handle is created for this 431 * purpose, and is discarded immediately after the promotion operation has been 432 * completed. 433 */ 434 typedef struct { 435 Alist *gh_depends; /* handle dependency list */ 436 Rt_map *gh_ownlmp; /* handle owners link-map */ 437 Lm_list *gh_ownlml; /* handle owners link-map list */ 438 uint_t gh_refcnt; /* handle reference count */ 439 uint_t gh_flags; /* handle flags (GPH_ values) */ 440 } Grp_hdl; 441 442 #define GPH_ZERO 0x0001 /* special handle for dlopen(0) */ 443 #define GPH_LDSO 0x0002 /* special handle for ld.so.1 */ 444 #define GPH_FIRST 0x0004 /* dlsym() can only use originating */ 445 /* dependency */ 446 #define GPH_FILTEE 0x0008 /* handle used to specify a filtee */ 447 #define GPH_INITIAL 0x0010 /* handle is initialized */ 448 #define GPH_NOPENDLAZY 0x0020 /* no pending lazy dependencies */ 449 /* remain for this handle */ 450 451 /* 452 * Define a Group Descriptor. 453 * 454 * Each dependency associated with a group handle is maintained by a group 455 * descriptor. The descriptor defines the associated dependency together with 456 * flags that indicate how the dependency can be used. 457 */ 458 typedef struct { 459 Rt_map *gd_depend; /* dependency */ 460 uint_t gd_flags; /* dependency flags (GPD_ values) */ 461 } Grp_desc; 462 463 #define GPD_DLSYM 0x0001 /* dependency available to dlsym() */ 464 #define GPD_RELOC 0x0002 /* dependency available to satisfy */ 465 /* relocation binding */ 466 #define GPD_ADDEPS 0x0004 /* dependencies of this dependency */ 467 /* should be added to handle */ 468 #define GPD_PARENT 0x0008 /* dependency is a parent */ 469 #define GPD_FILTER 0x0010 /* dependency is our filter */ 470 #define GPD_PROMOTE 0x0020 /* dependency is our RTLD_NOW */ 471 /* promoter */ 472 #define GPD_REMOVE 0x1000 /* descriptor is a candidate for */ 473 /* removal from the group */ 474 475 /* 476 * Define threading structures. For compatibility with libthread (T1_VERSION 1 477 * and TI_VERSION 2) our locking structure is sufficient to hold a mutex or a 478 * readers/writers lock. 479 */ 480 typedef struct { 481 union { 482 mutex_t l_mutex; 483 rwlock_t l_rwlock; 484 } u; 485 } Rt_lock; 486 487 typedef cond_t Rt_cond; 488 489 /* 490 * Define a dynamic section information descriptor. This parallels the entries 491 * in the .dynamic section and holds auxiliary information to implement lazy 492 * loading and filtee processing. 493 */ 494 typedef struct { 495 uint_t di_flags; 496 void *di_info; 497 } Dyninfo; 498 499 #define FLG_DI_STDFLTR 0x00001 /* .dynamic entry for DT_FILTER */ 500 #define FLG_DI_AUXFLTR 0x00002 /* .dynamic entry for DT_AUXILIARY */ 501 #define FLG_DI_SYMFLTR 0x00004 /* .dynamic entry for DT_SYMFILTER */ 502 /* and DT_SYMAUXILIARY */ 503 #define MSK_DI_FILTER 0x0000f /* mask for all filter possibilities */ 504 505 #define FLG_DI_POSFLAG1 0x00010 /* .dynamic entry for DT_POSFLAG_1 */ 506 #define FLG_DI_NEEDED 0x00020 /* .dynamic entry for DT_NEEDED */ 507 #define FLG_DI_LAZY 0x00100 /* lazy needed entry - preceded by */ 508 /* DF_P1_LAZYLOAD (DT_POSFLAG_1) */ 509 #define FLG_DI_GROUP 0x00200 /* group needed entry - preceded by */ 510 /* DF_P1_GROUPPERM (DT_POSFLAG_1) */ 511 512 #define FLG_DI_LDD_DONE 0x01000 /* entry has been processed (ldd) */ 513 #define FLG_DI_LAZYFAIL 0x02000 /* the lazy loading of this entry */ 514 /* failed */ 515 /* 516 * Data structure to track AVL tree of pathnames. This structure provides the 517 * basis of both the "not-found" node tree, and the "full-path" node tree. Both 518 * of these trees persist for the life of a process, although the "not-found" 519 * tree may be moved aside during a dlopen() or dlsym() fall back operation. 520 */ 521 typedef struct { 522 const char *pn_name; /* path name */ 523 avl_node_t pn_avl; /* avl book-keeping (see SGSOFFSETOF) */ 524 uint_t pn_hash; /* path name hash value */ 525 } PathNode; 526 527 /* 528 * Data structure to track AVL tree for full path names of objects that are 529 * loaded into memory. 530 */ 531 typedef struct { 532 PathNode fpn_node; /* path node */ 533 Rt_map *fpn_lmp; /* object link-map */ 534 } FullPathNode; 535 536 /* 537 * A given link-map can hold either a supplier or receiver copy 538 * relocation list, but not both. This union is used to overlap 539 * the space used for the two lists. 540 */ 541 typedef union { 542 Alist *rtc_r; /* receiver list (Rel_copy) */ 543 APlist *rtc_s; /* supplier list (Rt_map *) */ 544 } Rt_map_copy; 545 546 547 /* 548 * Link-map definition. 549 */ 550 struct rt_map { 551 /* 552 * BEGIN: Exposed to rtld_db - don't move, don't delete 553 */ 554 Link_map rt_public; /* public data */ 555 const char *rt_pathname; /* full pathname of loaded object */ 556 ulong_t rt_padstart; /* start of image (including padding) */ 557 ulong_t rt_padimlen; /* size of image (including padding */ 558 ulong_t rt_msize; /* total memory reservation range */ 559 uint_t rt_flags; /* state flags, see FLG below */ 560 uint_t rt_flags1; /* state flags1, see FL1 below */ 561 ulong_t rt_tlsmodid; /* TLS module id */ 562 /* 563 * END: Exposed to rtld_db - don't move, don't delete 564 */ 565 APlist *rt_alias; /* list of linked file names */ 566 APlist *rt_fpnode; /* list of FullpathNode AVL nodes */ 567 char *rt_runpath; /* LD_RUN_PATH and its equivalent */ 568 Alist *rt_runlist; /* Pdesc structures */ 569 APlist *rt_depends; /* list of dependencies */ 570 APlist *rt_callers; /* list of callers */ 571 APlist *rt_handles; /* dlopen handles */ 572 APlist *rt_groups; /* groups we're a member of */ 573 struct fct *rt_fct; /* file class table for this object */ 574 void *rt_priv; /* private data, object type specific */ 575 Lm_list *rt_list; /* link map list we belong to */ 576 uint_t rt_objfltrndx; /* object filtees .dynamic index */ 577 uint_t rt_symsfltrcnt; /* number of standard symbol filtees */ 578 uint_t rt_symafltrcnt; /* number of auxiliary symbol filtees */ 579 int rt_mode; /* usage mode, see RTLD mode flags */ 580 int rt_sortval; /* temporary buffer to traverse graph */ 581 uint_t rt_cycgroup; /* cyclic group */ 582 dev_t rt_stdev; /* device id and inode number for .so */ 583 rtld_ino_t rt_stino; /* multiple inclusion checks */ 584 const char *rt_origname; /* original pathname of loaded object */ 585 size_t rt_dirsz; /* and its size */ 586 size_t rt_lmsize; /* size of the link-map allocation */ 587 Rt_map_copy rt_copy; /* list of copy relocations */ 588 Audit_desc *rt_auditors; /* audit descriptor array */ 589 Audit_info *rt_audinfo; /* audit information descriptor */ 590 Syminfo *rt_syminfo; /* elf .syminfo section - here */ 591 /* because it is checked in */ 592 /* common code */ 593 Addr *rt_initarray; /* .initarray table */ 594 Addr *rt_finiarray; /* .finiarray table */ 595 Addr *rt_preinitarray; /* .preinitarray table */ 596 mmapobj_result_t *rt_mmaps; /* array of mapping information */ 597 uint_t rt_mmapcnt; /* and associated number */ 598 uint_t rt_initarraysz; /* size of .initarray table */ 599 uint_t rt_finiarraysz; /* size of .finiarray table */ 600 uint_t rt_preinitarraysz; /* size of .preinitarray table */ 601 Dyninfo *rt_dyninfo; /* .dynamic information descriptors */ 602 uint_t rt_dyninfocnt; /* count of dyninfo entries */ 603 uint_t rt_relacount; /* no. of RELATIVE relocations */ 604 uint_t rt_idx; /* hold index within linkmap list */ 605 uint_t rt_lazy; /* lazy dependencies pending */ 606 Xword rt_hwcap; /* hardware capabilities */ 607 Xword rt_sfcap; /* software capabilities */ 608 uint_t rt_cntl; /* link-map control list we belong to */ 609 uint_t rt_aflags; /* auditor flags, see LML_TFLG_AUD_ */ 610 /* address of _init */ 611 void (*rt_init)(void); 612 /* address of _fini */ 613 void (*rt_fini)(void); 614 /* link map symbol interpreter */ 615 Sym *(*rt_symintp)(Slookup *, Rt_map **, uint_t *, int *); 616 }; 617 618 #ifdef _SYSCALL32 619 /* 620 * Structure to allow 64-bit rtld_db to read 32-bit processes out of procfs. 621 */ 622 typedef union { 623 uint32_t rtc_r; 624 uint32_t rtc_s; 625 } Rt_map_copy32; 626 627 typedef struct rt_map32 { 628 /* 629 * BEGIN: Exposed to rtld_db - don't move, don't delete 630 */ 631 Link_map32 rt_public; 632 uint32_t rt_pathname; 633 uint32_t rt_padstart; 634 uint32_t rt_padimlen; 635 uint32_t rt_msize; 636 uint32_t rt_flags; 637 uint32_t rt_flags1; 638 uint32_t rt_tlsmodid; 639 /* 640 * END: Exposed to rtld_db - don't move, don't delete 641 */ 642 uint32_t rt_alias; 643 uint32_t rt_fpnode; 644 uint32_t rt_runpath; 645 uint32_t rt_runlist; 646 uint32_t rt_depends; 647 uint32_t rt_callers; 648 uint32_t rt_handles; 649 uint32_t rt_groups; 650 uint32_t rt_fct; 651 uint32_t rt_priv; 652 uint32_t rt_list; 653 uint32_t rt_objfltrndx; 654 uint32_t rt_symsfltrcnt; 655 uint32_t rt_symafltrcnt; 656 int32_t rt_mode; 657 int32_t rt_sortval; 658 uint32_t rt_cycgroup; 659 uint32_t rt_stdev; 660 uint32_t rt_stino; 661 uint32_t rt_origname; 662 uint32_t rt_dirsz; 663 Rt_map_copy32 rt_copy; 664 uint32_t rt_auditors; 665 uint32_t rt_audinfo; 666 uint32_t rt_syminfo; 667 uint32_t rt_initarray; 668 uint32_t rt_finiarray; 669 uint32_t rt_preinitarray; 670 uint32_t rt_mmaps; 671 uint32_t rt_mmapcnt; 672 uint32_t rt_initarraysz; 673 uint32_t rt_finiarraysz; 674 uint32_t rt_preinitarraysz; 675 uint32_t rt_dyninfo; 676 uint32_t rt_dyninfocnt; 677 uint32_t rt_relacount; 678 uint32_t rt_idx; 679 uint32_t rt_lazy; 680 uint32_t rt_hwcap; 681 uint32_t rt_sfcap; 682 uint32_t rt_cntl; 683 uint32_t rt_aflags; 684 uint32_t rt_init; 685 uint32_t rt_fini; 686 uint32_t rt_symintp; 687 } Rt_map32; 688 689 #endif /* _SYSCALL32 */ 690 691 /* 692 * Link map state flags. 693 */ 694 /* 695 * BEGIN: Exposed to rtld_db - don't move, don't delete 696 */ 697 #define FLG_RT_ISMAIN 0x00000001 /* object represents main executable */ 698 #define FLG_RT_IMGALLOC 0x00000002 /* image is allocated (not mmap'ed) */ 699 /* 700 * Available for r_debug version >= R_RTLDDB_VERSION5 701 */ 702 #define FLG_RT_RELOCED 0x00000004 /* object has been relocated */ 703 /* 704 * END: Exposed to rtld_db - don't move, don't delete 705 */ 706 #define FLG_RT_SETGROUP 0x00000008 /* group establishment required */ 707 #define FLG_RT_HWCAP 0x00000010 /* process $HWCAP expansion */ 708 #define FLG_RT_OBJECT 0x00000020 /* object processing (ie. .o's) */ 709 #define FLG_RT_NEWLOAD 0x00000040 /* object is newly loaded */ 710 #define FLG_RT_NODUMP 0x00000080 /* object can't be dldump(3x)'ed */ 711 #define FLG_RT_DELETE 0x00000100 /* object can be deleted */ 712 #define FLG_RT_ANALYZED 0x00000200 /* object has been analyzed */ 713 #define FLG_RT_INITDONE 0x00000400 /* objects .init has been completed */ 714 #define FLG_RT_TRANS 0x00000800 /* object is acting as a translator */ 715 #define FLG_RT_FIXED 0x00001000 /* image location is fixed */ 716 #define FLG_RT_PRELOAD 0x00002000 /* object was preloaded */ 717 #define FLG_RT_ALTER 0x00004000 /* alternative object used */ 718 #define FLG_RT_LOADFLTR 0x00008000 /* trigger filtee loading */ 719 #define FLG_RT_AUDIT 0x00010000 /* object is an auditor */ 720 #define FLG_RT_MODESET 0x00020000 /* MODE() has been initialized */ 721 #define FLG_RT_ANALZING 0x00040000 /* object is being analyzed */ 722 #define FLG_RT_INITFRST 0x00080000 /* execute .init first */ 723 #define FLG_RT_NOOPEN 0x00100000 /* dlopen() not allowed */ 724 #define FLG_RT_FINICLCT 0x00200000 /* fini has been collected (tsort) */ 725 #define FLG_RT_INITCALL 0x00400000 /* objects .init has been called */ 726 #define FLG_RT_OBJINTPO 0x00800000 /* object is a global interposer */ 727 #define FLG_RT_SYMINTPO 0x01000000 /* object contains symbol interposer */ 728 #define MSK_RT_INTPOSE 0x01800000 /* mask for all interposer */ 729 /* possibilities */ 730 #define FLG_RT_MOVE 0x02000000 /* object needs move operation */ 731 #define FLG_RT_TMPLIST 0x04000000 /* object is part of a temporary list */ 732 #define FLG_RT_REGSYMS 0x08000000 /* object has DT_REGISTER entries */ 733 #define FLG_RT_INITCLCT 0x10000000 /* init has been collected (tsort) */ 734 #define FLG_RT_HANDLE 0x20000000 /* generate a handle for this object */ 735 #define FLG_RT_RELOCING 0x40000000 /* object is being relocated */ 736 737 #define FL1_RT_COPYTOOK 0x00000001 /* copy relocation taken */ 738 739 #define FL1_RT_CONFSET 0x00000004 /* object was loaded by crle(1) */ 740 #define FL1_RT_NODEFLIB 0x00000008 /* ignore default library search */ 741 #define FL1_RT_ENDFILTE 0x00000010 /* filtee terminates filters search */ 742 #define FL1_RT_DISPREL 0x00000020 /* object has *disp* relocation */ 743 #define FL1_RT_DTFLAGS 0x00000040 /* DT_FLAGS element exists */ 744 745 #define FL1_RT_LDDSTUB 0x00000100 /* identify lddstub */ 746 #define FL1_RT_NOINIFIN 0x00000200 /* no .init or .fini exists */ 747 #define FL1_RT_USED 0x00000400 /* symbol referenced from this object */ 748 #define FL1_RT_SYMBOLIC 0x00000800 /* DF_SYMBOLIC was set - use */ 749 /* symbolic sym resolution */ 750 #define FL1_RT_OBJSFLTR 0x00001000 /* object is acting as a standard */ 751 #define FL1_RT_OBJAFLTR 0x00002000 /* or auxiliary filter */ 752 #define FL1_RT_SYMSFLTR 0x00004000 /* symbol is acting as a standard */ 753 #define FL1_RT_SYMAFLTR 0x00008000 /* or auxiliary filter */ 754 #define MSK_RT_FILTER 0x0000f000 /* mask for all filter possibilities */ 755 756 #define FL1_RT_TLSADD 0x00010000 /* objects TLS has been registered */ 757 #define FL1_RT_TLSSTAT 0x00020000 /* object requires static TLS */ 758 #define FL1_RT_DIRECT 0x00040000 /* object has DIRECT bindings enabled */ 759 #define FL1_RT_GLOBAUD 0x00080000 /* establish global auditing */ 760 761 /* 762 * Flags for the tls_modactivity() routine 763 */ 764 #define TM_FLG_MODADD 0x01 /* call tls_modadd() interface */ 765 #define TM_FLG_MODREM 0x02 /* call tls_modrem() interface */ 766 767 /* 768 * Macros for getting to exposed, link_map data (R_RTLDDB_VERSION <= 2). 769 */ 770 #define ADDR(X) ((X)->rt_public.l_addr) 771 #define NAME(X) ((X)->rt_public.l_name) 772 #define DYN(X) ((X)->rt_public.l_ld) 773 #define NEXT(X) ((X)->rt_public.l_next) 774 #define PREV(X) ((X)->rt_public.l_prev) 775 #define REFNAME(X) ((X)->rt_public.l_refname) 776 777 /* 778 * An Rt_map starts with a Link_map, followed by other information. 779 * ld.so.1 allocates Rt_map structures, and then casts them to Link_map, 780 * and back, depending on context. 781 * 782 * On some platforms, Rt_map can have a higher alignment requirement 783 * than Link_map. On such platforms, the cast from Link_map to Rt_map will 784 * draw an E_BAD_PTR_CAST_ALIGN warning from lint. Since we allocate 785 * the memory as the higher alignment Rt_map, we know that this is a safe 786 * conversion. The LINKMAP_TO_RTMAP macro is used to handle the conversion 787 * in a manner that satisfies lint. 788 */ 789 #ifdef lint 790 #define LINKMAP_TO_RTMAP(X) (Rt_map *)(void *)(X) 791 #else 792 #define LINKMAP_TO_RTMAP(X) (Rt_map *)(X) 793 #endif 794 795 /* 796 * Convenience macros for the common case of using 797 * NEXT()/PREV() and casting the result to (Rt_map *) 798 */ 799 #define NEXT_RT_MAP(X) LINKMAP_TO_RTMAP(NEXT(X)) 800 #define PREV_RT_MAP(X) LINKMAP_TO_RTMAP(PREV(X)) 801 802 /* 803 * Macros for getting to exposed, link_map data (R_RTLDDB_VERSION3). 804 */ 805 #define PATHNAME(X) ((X)->rt_pathname) 806 #define PADSTART(X) ((X)->rt_padstart) 807 #define PADIMLEN(X) ((X)->rt_padimlen) 808 #define MSIZE(X) ((X)->rt_msize) 809 #define FLAGS(X) ((X)->rt_flags) 810 #define FLAGS1(X) ((X)->rt_flags1) 811 812 /* 813 * Macros for getting to exposed, link_map data (R_RTLDDB_VERSION4). 814 */ 815 #define TLSMODID(X) ((X)->rt_tlsmodid) 816 817 /* 818 * Macros for getting to unexposed, link-map data. 819 */ 820 #define LMSIZE(X) ((X)->rt_lmsize) 821 #define AFLAGS(X) ((X)->rt_aflags) 822 #define ALIAS(X) ((X)->rt_alias) 823 #define FPNODE(X) ((X)->rt_fpnode) 824 #define INIT(X) ((X)->rt_init) 825 #define FINI(X) ((X)->rt_fini) 826 #define RPATH(X) ((X)->rt_runpath) 827 #define RLIST(X) ((X)->rt_runlist) 828 #define DEPENDS(X) ((X)->rt_depends) 829 #define CALLERS(X) ((X)->rt_callers) 830 #define HANDLES(X) ((X)->rt_handles) 831 #define GROUPS(X) ((X)->rt_groups) 832 #define FCT(X) ((X)->rt_fct) 833 #define SYMINTP(X) ((X)->rt_symintp) 834 #define LIST(X) ((X)->rt_list) 835 #define OBJFLTRNDX(X) ((X)->rt_objfltrndx) 836 #define SYMSFLTRCNT(X) ((X)->rt_symsfltrcnt) 837 #define SYMAFLTRCNT(X) ((X)->rt_symafltrcnt) 838 #define MODE(X) ((X)->rt_mode) 839 #define SORTVAL(X) ((X)->rt_sortval) 840 #define CYCGROUP(X) ((X)->rt_cycgroup) 841 #define STDEV(X) ((X)->rt_stdev) 842 #define STINO(X) ((X)->rt_stino) 843 #define ORIGNAME(X) ((X)->rt_origname) 844 #define DIRSZ(X) ((X)->rt_dirsz) 845 #define COPY_R(X) ((X)->rt_copy.rtc_r) 846 #define COPY_S(X) ((X)->rt_copy.rtc_s) 847 #define AUDITORS(X) ((X)->rt_auditors) 848 #define AUDINFO(X) ((X)->rt_audinfo) 849 #define SYMINFO(X) ((X)->rt_syminfo) 850 #define INITARRAY(X) ((X)->rt_initarray) 851 #define FINIARRAY(X) ((X)->rt_finiarray) 852 #define PREINITARRAY(X) ((X)->rt_preinitarray) 853 #define MMAPS(X) ((X)->rt_mmaps) 854 #define MMAPCNT(X) ((X)->rt_mmapcnt) 855 #define INITARRAYSZ(X) ((X)->rt_initarraysz) 856 #define FINIARRAYSZ(X) ((X)->rt_finiarraysz) 857 #define PREINITARRAYSZ(X) ((X)->rt_preinitarraysz) 858 #define DYNINFO(X) ((X)->rt_dyninfo) 859 #define DYNINFOCNT(X) ((X)->rt_dyninfocnt) 860 #define RELACOUNT(X) ((X)->rt_relacount) 861 #define IDX(X) ((X)->rt_idx) 862 #define LAZY(X) ((X)->rt_lazy) 863 #define CNTL(X) ((X)->rt_cntl) 864 #define HWCAP(X) ((X)->rt_hwcap) 865 #define SFCAP(X) ((X)->rt_sfcap) 866 867 /* 868 * Flags for tsorting. 869 */ 870 #define RT_SORT_FWD 0x01 /* topological sort (.fini) */ 871 #define RT_SORT_REV 0x02 /* reverse topological sort (.init) */ 872 #define RT_SORT_DELETE 0x10 /* process FLG_RT_DELETE objects */ 873 /* only (called via dlclose()) */ 874 #define RT_SORT_INTPOSE 0x20 /* process interposer objects */ 875 876 /* 877 * Flags for lookup_sym (and hence find_sym) routines. 878 */ 879 #define LKUP_DEFT 0x0000 /* simple lookup request */ 880 #define LKUP_SPEC 0x0001 /* special ELF lookup (allows address */ 881 /* resolutions to plt[] entries) */ 882 #define LKUP_LDOT 0x0002 /* indicates the original A_OUT */ 883 /* symbol had a leading `.' */ 884 #define LKUP_FIRST 0x0004 /* lookup symbol in first link map */ 885 /* only */ 886 #define LKUP_COPY 0x0008 /* lookup symbol for a COPY reloc, do */ 887 /* not bind to symbol at head */ 888 #define LKUP_STDRELOC 0x0010 /* lookup originates from a standard */ 889 /* relocation (elf_reloc()) */ 890 #define LKUP_SELF 0x0020 /* lookup symbol in ourself - undef */ 891 /* is valid */ 892 #define LKUP_WEAK 0x0040 /* relocation reference is weak */ 893 #define LKUP_NEXT 0x0080 /* request originates from RTLD_NEXT */ 894 #define LKUP_NODESCENT 0x0100 /* don't descend through dependencies */ 895 #define LKUP_NOFALLBACK 0x0200 /* don't fall back to loading */ 896 /* pending lazy dependencies */ 897 #define LKUP_DIRECT 0x0400 /* direct binding request */ 898 #define LKUP_SYMNDX 0x0800 /* establish symbol index */ 899 #define LKUP_SINGLETON 0x1000 /* search for a singleton symbol */ 900 #define LKUP_STANDARD 0x2000 /* standard lookup - originated from */ 901 /* head link-map element */ 902 #define LKUP_WORLD 0x4000 /* ensure world lookup */ 903 904 /* 905 * For the runtime linker to perform a symbol search, a number of data items 906 * related to the search are required. An Slookup data structure is used to 907 * convey this data to lookup_sym(), and in special cases, to other core 908 * routines that provide the implementation details for lookup_sym() 909 * 910 * The symbol name (sl_name), the caller (sl_cmap), and the link-map from which 911 * to start the search (sl_imap) are fundamental to the symbol search. The 912 * initial search link-map might get modified by the core routines that provide 913 * the implementation details for lookup_sym(). This modification accommodates 914 * requirements such as processing a handle, direct binding and interposition. 915 * The association between the caller and the potential destination also 916 * determines whether the destination is a candidate to search. 917 * 918 * The lookup identifier (sl_id) is used to identify a runtime linker operation. 919 * Within this operation, any lazy loads that fail are not re-examined. This 920 * technique keeps the overhead of processing a failed lazy load to a minimum. 921 * 922 * Symbol searches that originate from a relocation record are accompanied by 923 * the relocation index (sl_rsymndx), the symbol reference (sl_rsym) and 924 * possibly the relocation type (sl_rtype). This data provides for determining 925 * lazy loading, direct binding, and special symbol processing requirements 926 * such as copy relocations and singleton lookup. 927 * 928 * The symbols hash value is computed by lookup_sym, and propagated throughout 929 * the search engine. Note, occasionally the Slookup data is passed to a core 930 * routine that provides the implementation details for lookup_sym(), ie. 931 * elf_find_sym(), in which case the caller must initialize the hash value. 932 * 933 * The symbols binding information is established by lookup_sym() when the 934 * symbols relocation type is supplied. Weak bindings allow relocations to 935 * be set to zero should a symbol lookup fail. 936 * 937 * The flags allow the caller to control aspects of the search, including the 938 * interpretation of copy relocations, etc. Note, a number of flag settings 939 * are established in lookup_sym() from attributes of the symbol reference. 940 */ 941 struct slookup { 942 const char *sl_name; /* symbol name */ 943 Rt_map *sl_cmap; /* callers link-map */ 944 Rt_map *sl_imap; /* initial link-map to search */ 945 ulong_t sl_id; /* identifier for this lookup */ 946 ulong_t sl_hash; /* symbol hash value */ 947 ulong_t sl_rsymndx; /* referencing reloc symndx */ 948 Sym *sl_rsym; /* referencing symbol */ 949 uchar_t sl_rtype; /* relocation type associate with */ 950 /* symbol */ 951 uchar_t sl_bind; /* symbols binding (returned) */ 952 uint_t sl_flags; /* lookup flags */ 953 }; 954 955 #define SLOOKUP_INIT(sl, name, cmap, imap, id, hash, rsymndx, rsym, rtype, \ 956 flags) \ 957 (void) (sl.sl_name = (name), sl.sl_cmap = (cmap), sl.sl_imap = (imap), \ 958 sl.sl_id = (id), sl.sl_hash = (hash), sl.sl_rsymndx = (rsymndx), \ 959 sl.sl_rsym = (rsym), sl.sl_rtype = (rtype), sl.sl_bind = 0, \ 960 sl.sl_flags = (flags)) 961 962 /* 963 * Define a number of .plt lookup outcomes, for use in binding diagnostics. 964 */ 965 typedef enum { 966 PLT_T_NONE = 0, 967 PLT_T_21D, 968 PLT_T_24D, 969 PLT_T_U32, 970 PLT_T_U44, 971 PLT_T_FULL, 972 PLT_T_FAR, 973 PLT_T_NUM /* Must be last */ 974 } Pltbindtype; 975 976 /* 977 * Prototypes. 978 */ 979 extern ulong_t ld_entry_cnt; /* counter bumped on each entry to */ 980 /* ld.so.1. */ 981 extern Lm_list lml_main; /* main's link map list */ 982 extern Lm_list lml_rtld; /* rtld's link map list */ 983 extern Lm_list *lml_list[]; 984 985 extern Pltbindtype elf_plt_write(uintptr_t, uintptr_t, void *, uintptr_t, 986 Xword); 987 extern Rt_map *is_so_loaded(Lm_list *, const char *, int *); 988 extern Sym *lookup_sym(Slookup *, Rt_map **, uint_t *, int *); 989 extern int rt_dldump(Rt_map *, const char *, int, Addr); 990 991 #ifdef __cplusplus 992 } 993 #endif 994 995 #endif /* _RTLD_H */ 996