/* * 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) 1988 AT&T * All Rights Reserved * * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" /* * Programmatic interface to the run_time linker. */ #include "_synonyms.h" #include #include #include #include #include #include #include "_rtld.h" #include "_audit.h" #include "_elf.h" #include "msg.h" /* * Determine who called us - given a pc determine in which object it resides. * * For dlopen() the link map of the caller must be passed to load_so() so that * the appropriate search rules (4.x or 5.0) are used to locate any * dependencies. Also, if we've been called from a 4.x module it may be * necessary to fix the specified pathname so that it conforms with the 5.0 elf * rules. * * For dlsym() the link map of the caller is used to determine RTLD_NEXT * requests, together with requests based off of a dlopen(0). * For dladdr() this routines provides a generic means of scanning all loaded * segments. */ Rt_map * _caller(caddr_t cpc, int flags) { Lm_list * lml; Listnode * lnp; for (LIST_TRAVERSE(&dynlm_list, lnp, lml)) { Aliste off; Lm_cntl *lmc; for (ALIST_TRAVERSE(lml->lm_lists, off, lmc)) { Rt_map *lmp; for (lmp = lmc->lc_head; lmp; lmp = (Rt_map *)NEXT(lmp)) { Mmap *mmap; /* * Traverse this objects mappings testing * whether the pc falls within its range. */ for (mmap = MMAPS(lmp); mmap->m_vaddr; mmap++) { if ((cpc >= mmap->m_vaddr) && (cpc < (mmap->m_vaddr + mmap->m_msize))) return (lmp); } } } } /* * No mapping can be determined. If asked for a default, assume this * is from the executable. */ if (flags & CL_EXECDEF) return ((Rt_map *)lml_main.lm_head); return (0); } #pragma weak dlerror = _dlerror /* * External entry for dlerror(3dl). Returns a pointer to the string describing * the last occurring error. The last occurring error is cleared. */ char * _dlerror() { char *error; Rt_map *clmp; int entry; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); error = lasterr; lasterr = (char *)0; if (entry) leave(LIST(clmp)); return (error); } /* * Add a dependency as a group descriptor to a group handle. Returns 0 on * failure, ALE_EXISTS if the dependency already exists, or ALE_CREATE if it * is newly created. */ int hdl_add(Grp_hdl *ghp, Rt_map *lmp, uint_t flags) { Grp_desc *gdp; Aliste off; int found = ALE_CREATE; /* * Make sure this dependency hasn't already been recorded. */ for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) { if (gdp->gd_depend == lmp) { found = ALE_EXISTS; break; } } if (found == ALE_CREATE) { Grp_desc gd; /* * Create a new handle descriptor. */ gd.gd_depend = lmp; gd.gd_flags = 0; /* * Indicate this object is a part of this handles group. */ if (alist_append(&GROUPS(lmp), &ghp, sizeof (Grp_hdl *), AL_CNT_GROUPS) == 0) return (0); /* * Append the new dependency to this handle. */ if ((gdp = alist_append(&(ghp->gh_depends), &gd, sizeof (Grp_desc), AL_CNT_DEPENDS)) == 0) return (0); } gdp->gd_flags |= flags; if (found == ALE_CREATE) DBG_CALL(Dbg_file_hdl_action(ghp, lmp, DBG_DEP_ADD)); return (found); } /* * Allocate a handle and record its existence on the handle list for future * verification. */ Grp_hdl * hdl_alloc() { Grp_hdl *ghp; uint_t ndx; if ((ghp = calloc(sizeof (Grp_hdl), 1)) == 0) return (0); /* LINTED */ ndx = (uintptr_t)ghp % HDLIST_SZ; if (list_append(&hdl_list[ndx], ghp) == 0) { free(ghp); return (0); } return (ghp); } /* * Create a handle. */ Grp_hdl * hdl_create(Lm_list *lml, Rt_map *nlmp, Rt_map *clmp, uint_t flags) { Grp_hdl *ghp = 0, ** ghpp; uint_t hflags; Alist **alpp; Aliste off; /* * For dlopen(0) the handle is maintained as part of the link-map list, * otherwise it is associated with the referenced link-map. */ if (flags & GPH_ZERO) alpp = &(lml->lm_handle); else alpp = &(HANDLES(nlmp)); /* * Objects can contain multiple handles depending on the flags supplied. * Most RTLD flags pertain to the object itself and the bindings that it * can achieve. Multiple handles for these flags don't make sense. But * if the flag determines how the handle might be used, then multiple * handles may exist. Presently this only makes sense for RTLD_FIRST. * Determine if an appropriate handle already exists. */ hflags = flags & GPH_FIRST; for (ALIST_TRAVERSE(*alpp, off, ghpp)) { if (((*ghpp)->gh_flags & GPH_FIRST) == hflags) { ghp = *ghpp; break; } } if (ghp == 0) { DBG_CALL(Dbg_file_hdl_title(DBG_DEP_CREATE)); /* * If this is the first dlopen() request for this handle * allocate and initialize a new handle. */ if ((ghp = hdl_alloc()) == 0) return (0); if (alist_append(alpp, &ghp, sizeof (Grp_hdl *), AL_CNT_GROUPS) == 0) return (0); /* * Indicate that this object has been referenced. In truth a * reference hasn't yet occurred, it's a dlsym() that makes the * reference. However, we assume that anyone performing a * dlopen() will eventually call dlsym(), plus this makes for a * better diagnostic location rather than having to call * unused() after every dlsym() operation. */ if (nlmp) FLAGS1(nlmp) |= FL1_RT_USED; ghp->gh_refcnt = 1; ghp->gh_flags = flags; /* * A dlopen(0) handle is identified by the GPH_ZERO flag, the * head of the link-map list is defined as the owner. There is * no need to maintain a list of dependencies, for when this * handle is used (for dlsym()) a dynamic search through the * entire link-map list provides for searching all objects with * GLOBAL visibility. */ if (flags & GPH_ZERO) { ghp->gh_ownlmp = lml->lm_head; ghp->gh_ownlml = lml; } else { uint_t hflags = GPD_AVAIL; ghp->gh_ownlmp = nlmp; ghp->gh_ownlml = LIST(nlmp); /* * As an optimization, a handle for ld.so.1 itself * (required for libdl's filtering mechanism) shouldn't * search any dependencies of ld.so.1. Omitting * GDP_ADDEPS prevents the addition of any ld.so.1 * dependencies to this handle. */ if ((flags & GPH_LDSO) == 0) hflags |= GPD_ADDEPS; if (hdl_add(ghp, nlmp, hflags) == 0) return (0); } } else { /* * If a handle already exists bump its reference count. If it's * count was 0 then this handle previously existed but could not * be removed as part of a dlclose(). Remove this handle from * the orphan list as it's once again in use. Note that handles * associated with the link-map list itself (dlopen(0)) were * never deleted or removed to the orphan list. */ if ((ghp->gh_refcnt++ == 0) && ((ghp->gh_flags & (GPH_ZERO | GPH_STICKY)) == 0)) { uint_t ndx; /* LINTED */ ndx = (uintptr_t)ghp % HDLIST_SZ; list_delete(&hdl_list[HDLIST_ORP], ghp); (void) list_append(&hdl_list[ndx], ghp); if (DBG_ENABLED) { Aliste off; Grp_desc * gdp; DBG_CALL(Dbg_file_hdl_title(DBG_DEP_REINST)); for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) DBG_CALL(Dbg_file_hdl_action(ghp, gdp->gd_depend, DBG_DEP_ADD)); } } /* * Once a handle is referenced, remove any stick bit. */ ghp->gh_flags &= ~GPH_STICKY; } /* * If dlopen(..., RTLD_PARENT) add the caller to dependency list so that * it becomes part of this group. As we could be opened by different * parents this test is carried out every time a handle is requested. * Note that a parent doesn't provide symbols via dlsym() so it also * isn't necessary to add its dependencies to the handle. */ if (flags & GPH_PARENT) { if (hdl_add(ghp, clmp, GPD_PARENT) == 0) return (0); } return (ghp); } /* * Initialize a handle that has been created for an object that is already * loaded. The handle is initialized with the present dependencies of that * object. Once this initialization has occurred, any new objects that might * be loaded as dependencies (lazy-loading) are added to the handle as each new * object is loaded. */ int hdl_initialize(Grp_hdl *ghp, Rt_map *nlmp, Rt_map *clmp, int mode, int promote) { Aliste off; Grp_desc *gdp; /* * If the handle has already been initialized, and the initial object's * mode hasn't been promoted, there's no need to recompute the modes of * any dependencies. If the object we've added has just been opened, * the objects dependencies will not yet have been processed. These * dependencies will be added on later calls to load_one(). Otherwise, * this object already exists, so add all of its dependencies to the * handle were operating on. */ if (((ghp->gh_flags & GPH_INITIAL) && (promote == 0)) || ((FLAGS(nlmp) & FLG_RT_ANALYZED) == 0)) { ghp->gh_flags |= GPH_INITIAL; return (1); } DBG_CALL(Dbg_file_hdl_title(DBG_DEP_ADD)); for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) { Rt_map * lmp = gdp->gd_depend; Aliste off1; Bnd_desc ** bdpp; /* * If this dependency doesn't indicate that its dependencies * should be added to a handle, ignore it. This case identifies * a parent of a dlopen(RTLD_PARENT) request. */ if ((gdp->gd_flags & GPD_ADDEPS) == 0) continue; for (ALIST_TRAVERSE(DEPENDS(lmp), off1, bdpp)) { Bnd_desc *bdp = *bdpp; Rt_map *dlmp = bdp->b_depend; if ((bdp->b_flags & BND_NEEDED) == 0) continue; if (hdl_add(ghp, dlmp, (GPD_AVAIL | GPD_ADDEPS)) != 0) (void) update_mode(dlmp, MODE(dlmp), mode); else { /* * Something failed. Remove the new handle. */ (void) dlclose_intn(ghp, clmp); return (0); } } } ghp->gh_flags |= GPH_INITIAL; return (1); } /* * Sanity check a program-provided handle. */ static int hdl_validate(Grp_hdl *ghp) { Listnode *lnp; Grp_hdl *lghp; uint_t ndx; /* LINTED */ ndx = (uintptr_t)ghp % HDLIST_SZ; for (LIST_TRAVERSE(&hdl_list[ndx], lnp, lghp)) { if ((lghp == ghp) && (ghp->gh_refcnt != 0)) return (1); } return (0); } /* * Core dlclose activity. */ int dlclose_core(Grp_hdl *ghp, Rt_map *clmp) { /* * If we're already at atexit() there's no point processing further, * all objects have already been tsorted for fini processing. */ if ((rtld_flags & RT_FL_ATEXIT) != 0) return (0); /* * Diagnose what we're up to. */ if (ghp->gh_flags & GPH_ZERO) { DBG_CALL(Dbg_file_dlclose(LIST(clmp), MSG_ORIG(MSG_STR_ZERO), DBG_DLCLOSE_IGNORE)); } else { Rt_map *olmp; const char *owner; /* * Determine if we've an owner for this handle. */ if ((olmp = ghp->gh_ownlmp) != 0) owner = NAME(olmp); else owner = MSG_INTL(MSG_STR_UNKNOWN); DBG_CALL(Dbg_file_dlclose(LIST(clmp), owner, DBG_DLCLOSE_NULL)); } /* * Decrement reference count of this object. */ if (--(ghp->gh_refcnt)) return (0); /* * If this handle is special (dlopen(0)), then leave it around - it * has little overhead. */ if (ghp->gh_flags & GPH_ZERO) return (0); /* * This handle is no longer being referenced, remove it. */ return (remove_hdl(ghp, clmp, 0)); } /* * Internal dlclose activity. Called from user level or directly for internal * error cleanup. */ int dlclose_intn(Grp_hdl *ghp, Rt_map *clmp) { Rt_map *nlmp = 0; Lm_list *olml = 0; int error; /* * Although we're deleting object(s) it's quite possible that additional * objects get loaded from running the .fini section(s) of the objects * being deleted. These objects will have been added to the same * link-map list as those objects being deleted. Remember this list * for later investigation. */ olml = ghp->gh_ownlml; error = dlclose_core(ghp, clmp); /* * Determine whether the original link-map list still exists. In the * case of a dlclose of an alternative (dlmopen) link-map the whole * list may have been removed. */ if (olml) { Listnode *lnp; Lm_list *lml; for (LIST_TRAVERSE(&dynlm_list, lnp, lml)) { if (olml == lml) { nlmp = olml->lm_head; break; } } } load_completion(nlmp, clmp); return (error); } /* * Argument checking for dlclose. Only called via external entry. */ static int dlclose_check(void *handle, Rt_map *clmp) { Grp_hdl *ghp = (Grp_hdl *)handle; if (hdl_validate(ghp) == 0) { eprintf(LIST(clmp), ERR_FATAL, MSG_INTL(MSG_ARG_INVHNDL)); return (1); } return (dlclose_intn(ghp, clmp)); } #pragma weak dlclose = _dlclose /* * External entry for dlclose(3dl). Returns 0 for success, non-zero otherwise. */ int _dlclose(void *handle) { int error, entry; Rt_map *clmp; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); error = dlclose_check(handle, clmp); if (entry) leave(LIST(clmp)); return (error); } static uint_t lmid = 0; /* * The addition of new link-map lists is assumed to be in small quantities. * Here, we assign a unique link-map id for diagnostic use. Simply update the * running link-map count until we max out. */ int newlmid(Lm_list *lml) { char buffer[MSG_LMID_ALT_SIZE + 12]; if (lmid == UINT_MAX) { lml->lm_lmid = UINT_MAX; (void) strncpy(buffer, MSG_ORIG(MSG_LMID_MAXED), MSG_LMID_ALT_SIZE + 12); } else { lml->lm_lmid = lmid++; (void) snprintf(buffer, MSG_LMID_ALT_SIZE + 12, MSG_ORIG(MSG_LMID_FMT), MSG_ORIG(MSG_LMID_ALT), lml->lm_lmid); } if ((lml->lm_lmidstr = strdup(buffer)) == 0) return (0); return (1); } /* * Core dlopen activity. */ static Grp_hdl * dlmopen_core(Lm_list *lml, const char *path, int mode, Rt_map *clmp, uint_t flags, uint_t orig) { Rt_map *nlmp; Grp_hdl *ghp; Pnode *pnp; Aliste olmco, nlmco; Lm_cntl *lmc; DBG_CALL(Dbg_file_dlopen(clmp, (path ? path : MSG_ORIG(MSG_STR_ZERO)), mode)); /* * If the path specified is null then we're operating on global * objects. Associate a dummy handle with the link-map list. */ if (path == 0) { Grp_hdl *ghp; uint_t hflags = GPH_ZERO; int promote = 0; if (mode & RTLD_PARENT) hflags |= GPH_PARENT; if (mode & RTLD_FIRST) hflags |= GPH_FIRST; if ((ghp = hdl_create(lml, 0, clmp, hflags)) == 0) return (0); /* * Traverse the main link-map control list, updating the mode * of any objects as necessary. Call the relocation engine if * this mode promotes the existing state of any relocations. * crle()'s first pass loads all objects necessary for building * a configuration file, however none of them are relocated. * crle()'s second pass relocates objects in preparation for * dldump()'ing using dlopen(0, RTLD_NOW). */ if ((mode & (RTLD_NOW | RTLD_CONFGEN)) == RTLD_CONFGEN) return (ghp); for (nlmp = lml->lm_head; nlmp; nlmp = (Rt_map *)NEXT(nlmp)) { if (((MODE(nlmp) & RTLD_GLOBAL) == 0) || (FLAGS(nlmp) & FLG_RT_DELETE)) continue; if (update_mode(nlmp, MODE(nlmp), mode)) promote = 1; } if (promote) (void) relocate_lmc(lml, ALO_DATA, lml->lm_head); return (ghp); } /* * Fix the pathname. If this object expands to multiple paths (ie. * $ISALIST or $HWCAP have been used), then make sure the user has also * furnished the RTLD_FIRST flag. As yet, we don't support opening * more than one object at a time, so enforcing the RTLD_FIRST flag * provides flexibility should we be able to support dlopening more * than one object in the future. */ if ((pnp = LM_FIX_NAME(clmp)(path, clmp, orig)) == 0) { remove_lml(lml); return (0); } if (((pnp->p_orig & (PN_TKN_ISALIST | PN_TKN_HWCAP)) || pnp->p_next) && ((mode & RTLD_FIRST) == 0)) { remove_pnode(pnp); remove_lml(lml); eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLMODE_5)); return (0); } /* * Create a new link-map control list for this request, and load the * associated object. */ if ((lmc = alist_append(&(lml->lm_lists), 0, sizeof (Lm_cntl), AL_CNT_LMLISTS)) == 0) { remove_pnode(pnp); remove_lml(lml); return (0); } olmco = nlmco = (Aliste)((char *)lmc - (char *)lml->lm_lists); nlmp = load_one(lml, nlmco, pnp, clmp, mode, (flags | FLG_RT_HANDLE), &ghp); /* * Remove any expanded pathname infrastructure, and if the dependency * couldn't be loaded, cleanup. */ remove_pnode(pnp); if (nlmp == 0) { remove_cntl(lml, olmco); remove_lml(lml); return (0); } /* * If loading an auditor was requested, and the auditor already existed, * then the link-map returned will be to the original auditor. The new * link-map list that was initially created, and the associated link-map * control list are no longer needed. As the auditor is already loaded, * we're probably done, but fall through in case additional relocations * would be triggered by the mode of the caller. */ if ((flags & FLG_RT_AUDIT) && (LIST(nlmp) != lml)) { remove_cntl(lml, olmco); remove_lml(lml); lml = LIST(nlmp); olmco = 0; nlmco = ALO_DATA; } /* * Finish processing the objects associated with this request. */ if ((analyze_lmc(lml, nlmco, nlmp) == 0) || (relocate_lmc(lml, nlmco, nlmp) == 0)) { (void) dlclose_core(ghp, clmp); if (olmco && lm_salvage(lml, 1, olmco)) { remove_cntl(lml, olmco); remove_lml(lml); } return (0); } /* * After a successful load, any objects collected on the new link-map * control list will have been moved to the callers link-map control * list. This control list can now be deleted. */ if (olmco) remove_cntl(lml, olmco); return (ghp); } /* * Internal dlopen() activity. Called from user level or directly for internal * opens that require a handle. */ Grp_hdl * dlmopen_intn(Lm_list * lml, const char *path, int mode, Rt_map * clmp, uint_t flags, uint_t orig, int *loaded) { Rt_map *dlmp = 0; Grp_hdl *ghp; int objcnt; /* * Check for magic link-map list values: * * LM_ID_BASE: Operate on the PRIMARY (executables) link map * LM_ID_LDSO: Operation on ld.so.1's link map * LM_ID_NEWLM: Create a new link-map. */ if (lml == (Lm_list *)LM_ID_NEWLM) { if ((lml = calloc(sizeof (Lm_list), 1)) == 0) return (0); /* * Establish the new link-map flags from the callers and those * explicitly provided. */ lml->lm_tflags = LIST(clmp)->lm_tflags; if (flags & FLG_RT_AUDIT) { /* * Unset any auditing flags - an auditor shouldn't be * audited. Insure all audit dependencies are loaded. */ lml->lm_tflags &= ~LML_TFLG_AUD_MASK; lml->lm_tflags |= (LML_TFLG_NOLAZYLD | LML_TFLG_LOADFLTR); lml->lm_flags |= LML_FLG_NOAUDIT; } if ((list_append(&dynlm_list, lml) == 0) || (newlmid(lml) == 0)) { free(lml); return (0); } } else if ((uintptr_t)lml < LM_ID_NUM) { if ((uintptr_t)lml == LM_ID_BASE) lml = &lml_main; else if ((uintptr_t)lml == LM_ID_LDSO) lml = &lml_rtld; } objcnt = lml->lm_obj; /* * Open the required object on the associated link-map list. */ if ((ghp = dlmopen_core(lml, path, mode, clmp, flags, (orig | PN_SER_DLOPEN))) != 0) { /* * Establish the new link-map from which .init processing will * begin. Ignore .init firing when constructing a configuration * file (crle(1)). */ if ((mode & RTLD_CONFGEN) == 0) dlmp = ghp->gh_ownlmp; } /* * Return the number of objects loaded if required. This is used to * trigger used() processing on return from a dlopen(). */ if (loaded && dlmp) *loaded = lml->lm_obj - objcnt; load_completion(dlmp, clmp); return (ghp); } /* * Argument checking for dlopen. Only called via external entry. */ static Grp_hdl * dlmopen_check(Lm_list *lml, const char *path, int mode, Rt_map *clmp, int *loaded) { /* * Verify that a valid pathname has been supplied. */ if (path && (*path == '\0')) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLPATH)); return (0); } /* * Historically we've always verified the mode is either RTLD_NOW or * RTLD_LAZY. RTLD_NOLOAD is valid by itself. Use of LM_ID_NEWLM * requires a specific pathname, and use of RTLD_PARENT is meaningless. */ if ((mode & (RTLD_NOW | RTLD_LAZY | RTLD_NOLOAD)) == 0) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLMODE_1)); return (0); } if ((mode & (RTLD_NOW | RTLD_LAZY)) == (RTLD_NOW | RTLD_LAZY)) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLMODE_2)); return (0); } if ((lml == (Lm_list *)LM_ID_NEWLM) && (path == 0)) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLMODE_3)); return (0); } if ((lml == (Lm_list *)LM_ID_NEWLM) && (mode & RTLD_PARENT)) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLMODE_4)); return (0); } if (((mode & (RTLD_GROUP | RTLD_WORLD)) == 0) && ((mode & RTLD_NOLOAD) == 0)) mode |= (RTLD_GROUP | RTLD_WORLD); if ((mode & RTLD_NOW) && (rtld_flags2 & RT_FL2_BINDLAZY)) { mode &= ~RTLD_NOW; mode |= RTLD_LAZY; } return (dlmopen_intn(lml, path, mode, clmp, 0, 0, loaded)); } #pragma weak dlopen = _dlopen /* * External entry for dlopen(3dl). On success, returns a pointer (handle) to * the structure containing information about the newly added object, ie. can * be used by dlsym(). On failure, returns a null pointer. */ void * _dlopen(const char *path, int mode) { int entry, loaded = 0; Rt_map *clmp; Grp_hdl *ghp; Lm_list *lml; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); lml = LIST(clmp); ghp = dlmopen_check(lml, path, mode, clmp, &loaded); if (entry && ghp && loaded) unused(lml); if (entry) leave(lml); return ((void *)ghp); } /* * External entry for dlmopen(3dl). */ #pragma weak dlmopen = _dlmopen void * _dlmopen(Lmid_t lmid, const char *path, int mode) { int entry, loaded = 0; Rt_map *clmp; Grp_hdl *ghp; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); ghp = dlmopen_check((Lm_list *)lmid, path, mode, clmp, &loaded); if (entry && ghp && ghp->gh_ownlmp && loaded) unused(LIST(ghp->gh_ownlmp)); if (entry) leave(LIST(clmp)); return ((void *)ghp); } /* * Handle processing for dlsym. */ Sym * dlsym_handle(Grp_hdl * ghp, Slookup * slp, Rt_map ** _lmp, uint_t *binfo) { Rt_map *nlmp, * lmp = ghp->gh_ownlmp; Rt_map *clmp = slp->sl_cmap; const char *name = slp->sl_name; Sym *sym = 0; Slookup sl = *slp; sl.sl_flags = (LKUP_FIRST | LKUP_SPEC); /* * Continue processing a dlsym request. Lookup the required symbol in * each link-map specified by the handle. * * To leverage off of lazy loading, dlsym() requests can result in two * passes. The first descends the link-maps of any objects already in * the address space. If the symbol isn't located, and lazy * dependencies still exist, then a second pass is made to load these * dependencies if applicable. This model means that in the case where * a symbols exists in more than one object, the one located may not be * constant - this is the standard issue with lazy loading. In addition, * attempting to locate a symbol that doesn't exist will result in the * loading of all lazy dependencies on the given handle, which can * defeat some of the advantages of lazy loading (look out JVM). */ if (ghp->gh_flags & GPH_ZERO) { /* * If this symbol lookup is triggered from a dlopen(0) handle, * traverse the present link-map list looking for promiscuous * entries. */ for (nlmp = lmp; nlmp; nlmp = (Rt_map *)NEXT(nlmp)) { /* * If this handle indicates we're only to look in the * first object check whether we're done. */ if ((nlmp != lmp) && (ghp->gh_flags & GPH_FIRST)) return ((Sym *)0); if (!(MODE(nlmp) & RTLD_GLOBAL)) continue; if ((FLAGS(nlmp) & FLG_RT_DELETE) && ((FLAGS(clmp) & FLG_RT_DELETE) == 0)) continue; sl.sl_imap = nlmp; if (sym = LM_LOOKUP_SYM(clmp)(&sl, _lmp, binfo)) return (sym); } /* * If we're unable to locate the symbol and this link-map still * has pending lazy dependencies, start loading them in an * attempt to exhaust the search. Note that as we're already * traversing a dynamic linked list of link-maps there's no * need for elf_lazy_find_sym() to descend the link-maps itself. */ if (LIST(lmp)->lm_lazy) { DBG_CALL(Dbg_syms_lazy_rescan(LIST(lmp), name)); sl.sl_flags |= LKUP_NODESCENT; for (nlmp = lmp; nlmp; nlmp = (Rt_map *)NEXT(nlmp)) { if (!(MODE(nlmp) & RTLD_GLOBAL) || !LAZY(nlmp)) continue; if ((FLAGS(nlmp) & FLG_RT_DELETE) && ((FLAGS(clmp) & FLG_RT_DELETE) == 0)) continue; sl.sl_imap = nlmp; if (sym = elf_lazy_find_sym(&sl, _lmp, binfo)) return (sym); } } } else { /* * Traverse the dlopen() handle for the presently loaded * link-maps. */ Grp_desc * gdp; Aliste off; for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) { if ((gdp->gd_flags & GPD_AVAIL) == 0) continue; sl.sl_imap = gdp->gd_depend; if (sym = LM_LOOKUP_SYM(clmp)(&sl, _lmp, binfo)) return (sym); if (ghp->gh_flags & GPH_FIRST) return ((Sym *)0); } /* * If we're unable to locate the symbol and this link-map still * has pending lazy dependencies, start loading them in an * attempt to exhaust the search. */ if (LIST(lmp)->lm_lazy) { DBG_CALL(Dbg_syms_lazy_rescan(LIST(lmp), name)); for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) { nlmp = gdp->gd_depend; if (((gdp->gd_flags & GPD_AVAIL) == 0) || (LAZY(nlmp) == 0)) continue; sl.sl_imap = nlmp; if (sym = elf_lazy_find_sym(&sl, _lmp, binfo)) return (sym); } } } return ((Sym *)0); } /* * Core dlsym activity. Selects symbol lookup method from handle. */ void * dlsym_core(void *handle, const char *name, Rt_map *clmp, Rt_map **dlmp) { Sym *sym; Syminfo *sip; Slookup sl; uint_t binfo; sl.sl_name = name; sl.sl_cmap = clmp; sl.sl_hash = 0; sl.sl_rsymndx = 0; /* * Standard relocations are evaluated using the symbol index of the * associated relocation symbol. This index provides for loading * any lazy dependency and establishing a direct binding if necessary. * If a dlsym() operation originates from an object that contains a * symbol table entry for the same name, then establish the symbol * index so that any dependency requirements can be triggered. */ if (((intptr_t)handle < 0) && (sip = SYMINFO(clmp)) != 0) { sl.sl_imap = clmp; sl.sl_flags = LKUP_SYMNDX; sl.sl_hash = elf_hash(name); if ((sym = SYMINTP(clmp)(&sl, 0, 0)) != NULL) { sl.sl_rsymndx = (((ulong_t)sym - (ulong_t)SYMTAB(clmp)) / SYMENT(clmp)); } } if (handle == RTLD_NEXT) { Rt_map *nlmp; /* * If this handle is RTLD_NEXT determine whether a lazy load * from the caller might provide the next object. This mimics * the lazy loading initialization normally carried out by * lookup_sym(), however here, we must do this up-front, as * lookup_sym() will be used to inspect the next object. */ if (sl.sl_rsymndx) { /* LINTED */ sip = (Syminfo *)((char *)sip + (sl.sl_rsymndx * SYMINENT(clmp))); if ((sip->si_flags & SYMINFO_FLG_DIRECT) && (sip->si_boundto < SYMINFO_BT_LOWRESERVE)) (void) elf_lazy_load(clmp, sip->si_boundto, name); /* * Clear the symbol index, so as not to confuse * lookup_sym() of the next object. */ sl.sl_rsymndx = 0; } /* * If the handle is RTLD_NEXT start searching in the next link * map from the callers. Determine permissions from the * present link map. Indicate to lookup_sym() that we're on an * RTLD_NEXT request so that it will use the callers link map to * start any possible lazy dependency loading. */ sl.sl_imap = nlmp = (Rt_map *)NEXT(clmp); DBG_CALL(Dbg_syms_dlsym(clmp, name, (nlmp ? NAME(nlmp) : MSG_INTL(MSG_STR_NULL)), DBG_DLSYM_NEXT)); if (nlmp == 0) return (0); sl.sl_flags = LKUP_NEXT; sym = LM_LOOKUP_SYM(clmp)(&sl, dlmp, &binfo); } else if (handle == RTLD_SELF) { /* * If the handle is RTLD_SELF start searching from the caller. */ DBG_CALL(Dbg_syms_dlsym(clmp, name, NAME(clmp), DBG_DLSYM_SELF)); sl.sl_imap = clmp; sl.sl_flags = LKUP_SPEC; sym = LM_LOOKUP_SYM(clmp)(&sl, dlmp, &binfo); } else if (handle == RTLD_DEFAULT) { Rt_map *hlmp = LIST(clmp)->lm_head; /* * If the handle is RTLD_DEFAULT mimic the standard symbol * lookup as would be triggered by a relocation. */ DBG_CALL(Dbg_syms_dlsym(clmp, name, 0, DBG_DLSYM_DEFAULT)); sl.sl_imap = hlmp; sl.sl_flags = LKUP_SPEC; sym = LM_LOOKUP_SYM(clmp)(&sl, dlmp, &binfo); } else if (handle == RTLD_PROBE) { Rt_map *hlmp = LIST(clmp)->lm_head; /* * If the handle is RTLD_PROBE, mimic the standard symbol * lookup as would be triggered by a relocation, however do * not fall back to a lazy loading rescan if the symbol can't be * found within the currently loaded objects. Note, a lazy * loaded dependency required by the caller might still get * loaded to satisfy this request, but no exhaustive lazy load * rescan is carried out. */ DBG_CALL(Dbg_syms_dlsym(clmp, name, 0, DBG_DLSYM_PROBE)); sl.sl_imap = hlmp; sl.sl_flags = (LKUP_SPEC | LKUP_NOFALBACK); sym = LM_LOOKUP_SYM(clmp)(&sl, dlmp, &binfo); } else { Grp_hdl *ghp = (Grp_hdl *)handle; /* * Look in the shared object specified by the handle and in all * of its dependencies. */ DBG_CALL(Dbg_syms_dlsym(clmp, name, NAME(ghp->gh_ownlmp), DBG_DLSYM_DEF)); sym = LM_DLSYM(clmp)(ghp, &sl, dlmp, &binfo); } if (sym) { Lm_list *lml = LIST(clmp); Addr addr = sym->st_value; if (!(FLAGS(*dlmp) & FLG_RT_FIXED)) addr += ADDR(*dlmp); DBG_CALL(Dbg_bind_global(clmp, 0, 0, (Xword)-1, PLT_T_NONE, *dlmp, addr, sym->st_value, name, binfo)); if ((lml->lm_tflags | FLAGS1(clmp)) & LML_TFLG_AUD_SYMBIND) { uint_t sb_flags = LA_SYMB_DLSYM; /* LINTED */ uint_t symndx = (uint_t)(((Xword)sym - (Xword)SYMTAB(*dlmp)) / SYMENT(*dlmp)); addr = audit_symbind(clmp, *dlmp, sym, symndx, addr, &sb_flags); } return ((void *)addr); } else return (0); } /* * Internal dlsym activity. Called from user level or directly for internal * symbol lookup. */ void * dlsym_intn(void *handle, const char *name, Rt_map *clmp, Rt_map **dlmp) { Rt_map *llmp = 0; void *error; Aliste off; Grp_desc *gdp; /* * While looking for symbols it's quite possible that additional objects * get loaded from lazy loading. These objects will have been added to * the same link-map list as those objects on the handle. Remember this * list for later investigation. */ if ((handle == RTLD_NEXT) || (handle == RTLD_DEFAULT) || (handle == RTLD_SELF) || (handle == RTLD_PROBE)) llmp = LIST(clmp)->lm_tail; else { Grp_hdl * ghp = (Grp_hdl *)handle; if (ghp->gh_ownlmp) llmp = LIST(ghp->gh_ownlmp)->lm_tail; else { for (ALIST_TRAVERSE(ghp->gh_depends, off, gdp)) { if ((llmp = LIST(gdp->gd_depend)->lm_tail) != 0) break; } } } if ((error = dlsym_core(handle, name, clmp, dlmp)) == 0) { /* * Cache the error message, as Java tends to fall through this * code many times. */ if (nosym_str == 0) nosym_str = MSG_INTL(MSG_GEN_NOSYM); eprintf(LIST(clmp), ERR_FATAL, nosym_str, name); } load_completion(llmp, clmp); return (error); } /* * Argument checking for dlsym. Only called via external entry. */ static void * dlsym_check(void *handle, const char *name, Rt_map *clmp, Rt_map **dlmp) { /* * Verify the arguments. */ if (name == 0) { eprintf(LIST(clmp), ERR_FATAL, MSG_INTL(MSG_ARG_ILLSYM)); return (0); } if ((handle != RTLD_NEXT) && (handle != RTLD_DEFAULT) && (handle != RTLD_SELF) && (handle != RTLD_PROBE) && (hdl_validate((Grp_hdl *)handle) == 0)) { eprintf(LIST(clmp), ERR_FATAL, MSG_INTL(MSG_ARG_INVHNDL)); return (0); } return (dlsym_intn(handle, name, clmp, dlmp)); } #pragma weak dlsym = _dlsym /* * External entry for dlsym(). On success, returns the address of the specified * symbol. On error returns a null. */ void * _dlsym(void *handle, const char *name) { int entry; Rt_map *clmp, *dlmp = 0; void *addr; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); addr = dlsym_check(handle, name, clmp, &dlmp); if (dlmp) is_dep_ready(dlmp, clmp, DBG_WAIT_SYMBOL); if (entry && dlmp) is_dep_init(dlmp, clmp); if (entry) leave(LIST(clmp)); return (addr); } /* * Core dladdr activity. */ static void dladdr_core(Rt_map *clmp, void *addr, Dl_info *dlip, void **info, int flags) { /* * Set up generic information and any defaults. */ dlip->dli_fname = PATHNAME(clmp); dlip->dli_fbase = (void *)ADDR(clmp); dlip->dli_sname = 0; dlip->dli_saddr = 0; /* * Determine the nearest symbol to this address. */ LM_DLADDR(clmp)((ulong_t)addr, clmp, dlip, info, flags); } #pragma weak dladdr = _dladdr /* * External entry for dladdr(3dl) and dladdr1(3dl). Returns an information * structure that reflects the symbol closest to the address specified. */ int _dladdr(void *addr, Dl_info *dlip) { int entry, error; Rt_map *clmp; entry = enter(); /* * Use our calling technique to determine what object is associated * with the supplied address. If a caller can't be determined, * indicate the failure. */ if ((clmp = _caller((caddr_t)addr, CL_NONE)) == 0) { eprintf(0, ERR_FATAL, MSG_INTL(MSG_ARG_INVADDR), EC_NATPTR(addr)); error = 0; } else { dladdr_core(clmp, addr, dlip, 0, 0); error = 1; } if (entry) leave(0); return (error); } #pragma weak dladdr1 = _dladdr1 int _dladdr1(void *addr, Dl_info *dlip, void **info, int flags) { int entry, error = 0; Rt_map *clmp; /* * Validate any flags. */ if (flags) { int request; if (((request = (flags & RTLD_DL_MASK)) != RTLD_DL_SYMENT) && (request != RTLD_DL_LINKMAP)) { eprintf(0, ERR_FATAL, MSG_INTL(MSG_ARG_ILLFLAGS), flags); return (0); } if (info == 0) { eprintf(0, ERR_FATAL, MSG_INTL(MSG_ARG_ILLINFO), flags); return (0); } } entry = enter(); /* * Use our calling technique to determine what object is associated * with the supplied address. If a caller can't be determined, * indicate the failure. */ if ((clmp = _caller((caddr_t)addr, CL_NONE)) == 0) { eprintf(0, ERR_FATAL, MSG_INTL(MSG_ARG_INVADDR), EC_NATPTR(addr)); error = 0; } else { dladdr_core(clmp, addr, dlip, info, flags); error = 1; } if (entry) leave(0); return (error); } /* * Core dldump activity. */ static int dldump_core(Lm_list *lml, const char *ipath, const char *opath, int flags) { Addr addr = 0; Rt_map *lmp; /* * Verify any arguments first. */ if ((!opath || (*opath == '\0')) || (ipath && (*ipath == '\0'))) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLPATH)); return (1); } /* * If an input file is specified make sure its one of our dependencies * on the main link-map list. Note, this has really all evolved for * crle(), which uses libcrle.so on an alternative link-map to trigger * dumping objects from the main link-map list. If we ever want to * dump objects from alternative link-maps, this model is going to * have to be revisited. */ if (ipath) { if ((lmp = is_so_loaded(&lml_main, ipath, 0)) == 0) lmp = is_so_loaded(&lml_main, ipath, 1); if (lmp == 0) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_NOFILE), ipath); return (1); } if (FLAGS(lmp) & FLG_RT_ALTER) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_ALTER), ipath); return (1); } if (FLAGS(lmp) & FLG_RT_NODUMP) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_GEN_NODUMP), ipath); return (1); } } else lmp = lml_main.lm_head; DBG_CALL(Dbg_file_dldump(lmp, opath, flags)); /* * If the object being dump'ed isn't fixed identify its mapping. */ if (!(FLAGS(lmp) & FLG_RT_FIXED)) addr = ADDR(lmp); /* * As rt_dldump() will effectively lazy load the necessary support * libraries, make sure ld.so.1 is initialized for plt relocations. */ if (elf_rtld_load() == 0) return (0); /* * Dump the required image. */ return (rt_dldump(lmp, opath, flags, addr)); } #pragma weak dldump = _dldump /* * External entry for dldump(3c). Returns 0 on success, non-zero otherwise. */ int _dldump(const char *ipath, const char *opath, int flags) { int error, entry; Rt_map *clmp; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); error = dldump_core(LIST(clmp), ipath, opath, flags); if (entry) leave(LIST(clmp)); return (error); } /* * get_linkmap_id() translates Lm_list * pointers to the Link_map id as used by * the rtld_db and dlmopen() interfaces. It checks to see if the Link_map is * one of the primary ones and if so returns it's special token: * LM_ID_BASE * LM_ID_LDSO * * If it's not one of the primary link_map id's it will instead returns a * pointer to the Lm_list structure which uniquely identifies the Link_map. */ Lmid_t get_linkmap_id(Lm_list *lml) { if (lml->lm_flags & LML_FLG_BASELM) return (LM_ID_BASE); if (lml->lm_flags & LML_FLG_RTLDLM) return (LM_ID_LDSO); return ((Lmid_t)lml); } /* * Extract information for a dlopen() handle. */ static int dlinfo_core(void *handle, int request, void *p, Rt_map *clmp) { Lm_list *lml = LIST(clmp); Rt_map *lmp; if ((request > RTLD_DI_MAX) || (p == 0)) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLVAL)); return (-1); } /* * Return configuration cache name and address. */ if (request == RTLD_DI_CONFIGADDR) { Dl_info *dlip = (Dl_info *)p; if ((config->c_name == 0) || (config->c_bgn == 0) || (config->c_end == 0)) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_NOCONFIG)); return (-1); } dlip->dli_fname = config->c_name; dlip->dli_fbase = (void *)config->c_bgn; return (0); } /* * Return profiled object name (used by ldprof audit library). */ if (request == RTLD_DI_PROFILENAME) { if (profile_name == 0) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_NOPROFNAME)); return (-1); } *(const char **)p = profile_name; return (0); } if (request == RTLD_DI_PROFILEOUT) { /* * If a profile destination directory hasn't been specified * provide a default. */ if (profile_out == 0) profile_out = MSG_ORIG(MSG_PTH_VARTMP); *(const char **)p = profile_out; return (0); } /* * Obtain or establish a termination signal. */ if (request == RTLD_DI_GETSIGNAL) { *(int *)p = killsig; return (0); } if (request == RTLD_DI_SETSIGNAL) { sigset_t set; int sig = *(int *)p; /* * Determine whether the signal is in range. */ (void) sigfillset(&set); if (sigismember(&set, sig) != 1) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_INVSIG), sig); return (-1); } killsig = sig; return (0); } /* * For any other request a link-map is required. Verify the handle. */ if (handle == RTLD_SELF) lmp = clmp; else { Grp_hdl * ghp = (Grp_hdl *)handle; if (!hdl_validate(ghp)) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_INVHNDL)); return (-1); } lmp = ghp->gh_ownlmp; } /* * Obtain the process arguments, environment and auxv. Note, as the * environment can be modified by the user (putenv(3c)), reinitialize * the environment pointer on each request. */ if (request == RTLD_DI_ARGSINFO) { Dl_argsinfo *aip = (Dl_argsinfo *)p; Lm_list *lml = LIST(lmp); *aip = argsinfo; if (lml->lm_flags & LML_FLG_ENVIRON) aip->dla_envp = *(lml->lm_environ); return (0); } /* * Return Lmid_t of the Link-Map list that the specified object is * loaded on. */ if (request == RTLD_DI_LMID) { *(Lmid_t *)p = get_linkmap_id(LIST(lmp)); return (0); } /* * Return a pointer to the Link-Map structure associated with the * specified object. */ if (request == RTLD_DI_LINKMAP) { *(Link_map **)p = (Link_map *)lmp; return (0); } /* * Return search path information, or the size of the buffer required * to store the information. */ if ((request == RTLD_DI_SERINFO) || (request == RTLD_DI_SERINFOSIZE)) { Pnode *dir, *dirlist = (Pnode *)0; Dl_serinfo *info; Dl_serpath *path; char *strs; size_t size = sizeof (Dl_serinfo); uint_t cnt = 0; info = (Dl_serinfo *)p; path = &info->dls_serpath[0]; strs = (char *)&info->dls_serpath[info->dls_cnt]; /* * Traverse search path entries for this object. */ while ((dir = get_next_dir(&dirlist, lmp, 0)) != 0) { size_t _size; if (dir->p_name == 0) continue; /* * If configuration information exists, it's possible * this path has been identified as non-existent, if so * ignore it. */ if (dir->p_info) { Rtc_obj *dobj = (Rtc_obj *)dir->p_info; if (dobj->co_flags & RTC_OBJ_NOEXIST) continue; } /* * Keep track of search path count and total info size. */ if (cnt++) size += sizeof (Dl_serpath); _size = strlen(dir->p_name) + 1; size += _size; if (request == RTLD_DI_SERINFOSIZE) continue; /* * If we're filling in search path information, confirm * there's sufficient space. */ if (size > info->dls_size) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_SERSIZE), EC_OFF(info->dls_size)); return (-1); } if (cnt > info->dls_cnt) { eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_SERCNT), info->dls_cnt); return (-1); } /* * Append the path to the information buffer. */ (void) strcpy(strs, dir->p_name); path->dls_name = strs; path->dls_flags = dir->p_orig; strs = strs + _size; path++; } /* * If we're here to size the search buffer fill it in. */ if (request == RTLD_DI_SERINFOSIZE) { info->dls_size = size; info->dls_cnt = cnt; } } /* * Return the origin of the object associated with this link-map. * Basically return the dirname(1) of the objects fullpath. */ if (request == RTLD_DI_ORIGIN) { char *str = (char *)p; if (DIRSZ(lmp) == 0) (void) fullpath(lmp, 0); (void) strncpy(str, ORIGNAME(lmp), DIRSZ(lmp)); str += DIRSZ(lmp); *str = '\0'; return (0); } return (0); } #pragma weak dlinfo = _dlinfo /* * External entry for dlinfo(3dl). */ int _dlinfo(void *handle, int request, void *p) { int error, entry; Rt_map *clmp; entry = enter(); clmp = _caller(caller(), CL_EXECDEF); error = dlinfo_core(handle, request, p, clmp); if (entry) leave(LIST(clmp)); return (error); }