--- /dev/null
+/* $Id$
+*/
+
+/*
+ * REACTOS ELF LOADER
+ *
+ * ELF run-time linker, ported from FreeBSD by KJK::Hyperion as part of the ELF
+ * support initiative. Original copyright, licensing and disclaimers follow
+ */
+
+/*-
+ * Copyright 1996, 1997, 1998, 1999, 2000 John D. Polstra.
+ * Copyright 2003 Alexander Kabaev <kan@FreeBSD.ORG>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD: src/libexec/rtld-elf/rtld.c,v 1.101 2004/11/02 09:42:21 ssouhlal Exp $
+ */
+
+/*
+ * Dynamic linker for ELF.
+ *
+ * John Polstra <jdp@polstra.com>.
+ */
+
+#include <ntdll.h>
+#define NDEBUG
+#include <debug.h>
+
+#if 0
+
+#ifndef __GNUC__
+#error "GCC is needed to compile this file"
+#endif
+
+#include <sys/param.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include <dlfcn.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "debug.h"
+#include "rtld.h"
+#include "libmap.h"
+#include "rtld_tls.h"
+
+#ifndef COMPAT_32BIT
+#define PATH_RTLD "/libexec/ld-elf.so.1"
+#else
+#define PATH_RTLD "/libexec/ld-elf32.so.1"
+#endif
+
+/* Types. */
+typedef void (*func_ptr_type)();
+typedef void * (*path_enum_proc) (const char *path, size_t len, void *arg);
+
+/*
+ * This structure provides a reentrant way to keep a list of objects and
+ * check which ones have already been processed in some way.
+ */
+typedef struct Struct_DoneList {
+ const Obj_Entry **objs; /* Array of object pointers */
+ unsigned int num_alloc; /* Allocated size of the array */
+ unsigned int num_used; /* Number of array slots used */
+} DoneList;
+
+/*
+ * Function declarations.
+ */
+static const char *basename(const char *);
+static void die(void);
+static void digest_dynamic(Obj_Entry *, int);
+static Obj_Entry *digest_phdr(const Elf_Phdr *, int, caddr_t, const char *);
+static Obj_Entry *dlcheck(void *);
+static int do_search_info(const Obj_Entry *obj, int, struct dl_serinfo *);
+static bool donelist_check(DoneList *, const Obj_Entry *);
+static void errmsg_restore(char *);
+static char *errmsg_save(void);
+static void *fill_search_info(const char *, size_t, void *);
+static char *find_library(const char *, const Obj_Entry *);
+static const char *gethints(void);
+static void init_dag(Obj_Entry *);
+static void init_dag1(Obj_Entry *root, Obj_Entry *obj, DoneList *);
+static void init_rtld(caddr_t);
+static void initlist_add_neededs(Needed_Entry *needed, Objlist *list);
+static void initlist_add_objects(Obj_Entry *obj, Obj_Entry **tail,
+ Objlist *list);
+static bool is_exported(const Elf_Sym *);
+static void linkmap_add(Obj_Entry *);
+static void linkmap_delete(Obj_Entry *);
+static int load_needed_objects(Obj_Entry *);
+static int load_preload_objects(void);
+static Obj_Entry *load_object(char *);
+static Obj_Entry *obj_from_addr(const void *);
+static void objlist_call_fini(Objlist *);
+static void objlist_call_init(Objlist *);
+static void objlist_clear(Objlist *);
+static Objlist_Entry *objlist_find(Objlist *, const Obj_Entry *);
+static void objlist_init(Objlist *);
+static void objlist_push_head(Objlist *, Obj_Entry *);
+static void objlist_push_tail(Objlist *, Obj_Entry *);
+static void objlist_remove(Objlist *, Obj_Entry *);
+static void objlist_remove_unref(Objlist *);
+static void *path_enumerate(const char *, path_enum_proc, void *);
+static int relocate_objects(Obj_Entry *, bool, Obj_Entry *);
+static int rtld_dirname(const char *, char *);
+static void rtld_exit(void);
+static char *search_library_path(const char *, const char *);
+static const void **get_program_var_addr(const char *name);
+static void set_program_var(const char *, const void *);
+static const Elf_Sym *symlook_default(const char *, unsigned long hash,
+ const Obj_Entry *refobj, const Obj_Entry **defobj_out, bool in_plt);
+static const Elf_Sym *symlook_list(const char *, unsigned long,
+ Objlist *, const Obj_Entry **, bool in_plt, DoneList *);
+static void trace_loaded_objects(Obj_Entry *obj);
+static void unlink_object(Obj_Entry *);
+static void unload_object(Obj_Entry *);
+static void unref_dag(Obj_Entry *);
+static void ref_dag(Obj_Entry *);
+
+void r_debug_state(struct r_debug*, struct link_map*);
+
+/*
+ * Data declarations.
+ */
+static char *error_message; /* Message for dlerror(), or NULL */
+struct r_debug r_debug; /* for GDB; */
+static bool libmap_disable; /* Disable libmap */
+static bool trust; /* False for setuid and setgid programs */
+static char *ld_bind_now; /* Environment variable for immediate binding */
+static char *ld_debug; /* Environment variable for debugging */
+static char *ld_library_path; /* Environment variable for search path */
+static char *ld_preload; /* Environment variable for libraries to
+ load first */
+static char *ld_tracing; /* Called from ldd to print libs */
+static Obj_Entry *obj_list; /* Head of linked list of shared objects */
+static Obj_Entry **obj_tail; /* Link field of last object in list */
+static Obj_Entry *obj_main; /* The main program shared object */
+static Obj_Entry obj_rtld; /* The dynamic linker shared object */
+static unsigned int obj_count; /* Number of objects in obj_list */
+
+static Objlist list_global = /* Objects dlopened with RTLD_GLOBAL */
+ STAILQ_HEAD_INITIALIZER(list_global);
+static Objlist list_main = /* Objects loaded at program startup */
+ STAILQ_HEAD_INITIALIZER(list_main);
+static Objlist list_fini = /* Objects needing fini() calls */
+ STAILQ_HEAD_INITIALIZER(list_fini);
+
+static Elf_Sym sym_zero; /* For resolving undefined weak refs. */
+
+#define GDB_STATE(s,m) r_debug.r_state = s; r_debug_state(&r_debug,m);
+
+extern Elf_Dyn _DYNAMIC;
+#pragma weak _DYNAMIC
+#ifndef RTLD_IS_DYNAMIC
+#define RTLD_IS_DYNAMIC() (&_DYNAMIC != NULL)
+#endif
+
+/*
+ * These are the functions the dynamic linker exports to application
+ * programs. They are the only symbols the dynamic linker is willing
+ * to export from itself.
+ */
+static func_ptr_type exports[] = {
+ (func_ptr_type) &_rtld_error,
+ (func_ptr_type) &dlclose,
+ (func_ptr_type) &dlerror,
+ (func_ptr_type) &dlopen,
+ (func_ptr_type) &dlsym,
+ (func_ptr_type) &dladdr,
+ (func_ptr_type) &dllockinit,
+ (func_ptr_type) &dlinfo,
+ (func_ptr_type) &_rtld_thread_init,
+#ifdef __i386__
+ (func_ptr_type) &___tls_get_addr,
+#endif
+ (func_ptr_type) &__tls_get_addr,
+ (func_ptr_type) &_rtld_allocate_tls,
+ (func_ptr_type) &_rtld_free_tls,
+ NULL
+};
+
+/*
+ * Global declarations normally provided by crt1. The dynamic linker is
+ * not built with crt1, so we have to provide them ourselves.
+ */
+char *__progname;
+char **environ;
+
+/*
+ * Globals to control TLS allocation.
+ */
+size_t tls_last_offset; /* Static TLS offset of last module */
+size_t tls_last_size; /* Static TLS size of last module */
+size_t tls_static_space; /* Static TLS space allocated */
+int tls_dtv_generation = 1; /* Used to detect when dtv size changes */
+int tls_max_index = 1; /* Largest module index allocated */
+
+/*
+ * Fill in a DoneList with an allocation large enough to hold all of
+ * the currently-loaded objects. Keep this as a macro since it calls
+ * alloca and we want that to occur within the scope of the caller.
+ */
+#define donelist_init(dlp) \
+ ((dlp)->objs = alloca(obj_count * sizeof (dlp)->objs[0]), \
+ assert((dlp)->objs != NULL), \
+ (dlp)->num_alloc = obj_count, \
+ (dlp)->num_used = 0)
+
+/*
+ * Main entry point for dynamic linking. The first argument is the
+ * stack pointer. The stack is expected to be laid out as described
+ * in the SVR4 ABI specification, Intel 386 Processor Supplement.
+ * Specifically, the stack pointer points to a word containing
+ * ARGC. Following that in the stack is a null-terminated sequence
+ * of pointers to argument strings. Then comes a null-terminated
+ * sequence of pointers to environment strings. Finally, there is a
+ * sequence of "auxiliary vector" entries.
+ *
+ * The second argument points to a place to store the dynamic linker's
+ * exit procedure pointer and the third to a place to store the main
+ * program's object.
+ *
+ * The return value is the main program's entry point.
+ */
+func_ptr_type
+_rtld(Elf_Addr *sp, func_ptr_type *exit_proc, Obj_Entry **objp)
+{
+ Elf_Auxinfo *aux_info[AT_COUNT];
+ int i;
+ int argc;
+ char **argv;
+ char **env;
+ Elf_Auxinfo *aux;
+ Elf_Auxinfo *auxp;
+ const char *argv0;
+ Objlist_Entry *entry;
+ Obj_Entry *obj;
+ Obj_Entry **preload_tail;
+ Objlist initlist;
+ int lockstate;
+
+ /*
+ * On entry, the dynamic linker itself has not been relocated yet.
+ * Be very careful not to reference any global data until after
+ * init_rtld has returned. It is OK to reference file-scope statics
+ * and string constants, and to call static and global functions.
+ */
+
+ /* Find the auxiliary vector on the stack. */
+ argc = *sp++;
+ argv = (char **) sp;
+ sp += argc + 1; /* Skip over arguments and NULL terminator */
+ env = (char **) sp;
+ while (*sp++ != 0) /* Skip over environment, and NULL terminator */
+ ;
+ aux = (Elf_Auxinfo *) sp;
+
+ /* Digest the auxiliary vector. */
+ for (i = 0; i < AT_COUNT; i++)
+ aux_info[i] = NULL;
+ for (auxp = aux; auxp->a_type != AT_NULL; auxp++) {
+ if (auxp->a_type < AT_COUNT)
+ aux_info[auxp->a_type] = auxp;
+ }
+
+ /* Initialize and relocate ourselves. */
+ assert(aux_info[AT_BASE] != NULL);
+ init_rtld((caddr_t) aux_info[AT_BASE]->a_un.a_ptr);
+
+ __progname = obj_rtld.path;
+ argv0 = argv[0] != NULL ? argv[0] : "(null)";
+ environ = env;
+
+ trust = !issetugid();
+
+ ld_bind_now = getenv(LD_ "BIND_NOW");
+ if (trust) {
+ ld_debug = getenv(LD_ "DEBUG");
+ libmap_disable = getenv(LD_ "LIBMAP_DISABLE") != NULL;
+ ld_library_path = getenv(LD_ "LIBRARY_PATH");
+ ld_preload = getenv(LD_ "PRELOAD");
+ }
+ ld_tracing = getenv(LD_ "TRACE_LOADED_OBJECTS");
+
+ if (ld_debug != NULL && *ld_debug != '\0')
+ debug = 1;
+ dbg("%s is initialized, base address = %p", __progname,
+ (caddr_t) aux_info[AT_BASE]->a_un.a_ptr);
+ dbg("RTLD dynamic = %p", obj_rtld.dynamic);
+ dbg("RTLD pltgot = %p", obj_rtld.pltgot);
+
+ /*
+ * Load the main program, or process its program header if it is
+ * already loaded.
+ */
+ if (aux_info[AT_EXECFD] != NULL) { /* Load the main program. */
+ int fd = aux_info[AT_EXECFD]->a_un.a_val;
+ dbg("loading main program");
+ obj_main = map_object(fd, argv0, NULL);
+ close(fd);
+ if (obj_main == NULL)
+ die();
+ } else { /* Main program already loaded. */
+ const Elf_Phdr *phdr;
+ int phnum;
+ caddr_t entry;
+
+ dbg("processing main program's program header");
+ assert(aux_info[AT_PHDR] != NULL);
+ phdr = (const Elf_Phdr *) aux_info[AT_PHDR]->a_un.a_ptr;
+ assert(aux_info[AT_PHNUM] != NULL);
+ phnum = aux_info[AT_PHNUM]->a_un.a_val;
+ assert(aux_info[AT_PHENT] != NULL);
+ assert(aux_info[AT_PHENT]->a_un.a_val == sizeof(Elf_Phdr));
+ assert(aux_info[AT_ENTRY] != NULL);
+ entry = (caddr_t) aux_info[AT_ENTRY]->a_un.a_ptr;
+ if ((obj_main = digest_phdr(phdr, phnum, entry, argv0)) == NULL)
+ die();
+ }
+
+ obj_main->path = xstrdup(argv0);
+ obj_main->mainprog = true;
+
+ /*
+ * Get the actual dynamic linker pathname from the executable if
+ * possible. (It should always be possible.) That ensures that
+ * gdb will find the right dynamic linker even if a non-standard
+ * one is being used.
+ */
+ if (obj_main->interp != NULL &&
+ strcmp(obj_main->interp, obj_rtld.path) != 0) {
+ free(obj_rtld.path);
+ obj_rtld.path = xstrdup(obj_main->interp);
+ __progname = obj_rtld.path;
+ }
+
+ digest_dynamic(obj_main, 0);
+
+ linkmap_add(obj_main);
+ linkmap_add(&obj_rtld);
+
+ /* Link the main program into the list of objects. */
+ *obj_tail = obj_main;
+ obj_tail = &obj_main->next;
+ obj_count++;
+ /* Make sure we don't call the main program's init and fini functions. */
+ obj_main->init = obj_main->fini = (Elf_Addr)NULL;
+
+ /* Initialize a fake symbol for resolving undefined weak references. */
+ sym_zero.st_info = ELF_ST_INFO(STB_GLOBAL, STT_NOTYPE);
+ sym_zero.st_shndx = SHN_UNDEF;
+
+ if (!libmap_disable)
+ libmap_disable = (bool)lm_init();
+
+ dbg("loading LD_PRELOAD libraries");
+ if (load_preload_objects() == -1)
+ die();
+ preload_tail = obj_tail;
+
+ dbg("loading needed objects");
+ if (load_needed_objects(obj_main) == -1)
+ die();
+
+ /* Make a list of all objects loaded at startup. */
+ for (obj = obj_list; obj != NULL; obj = obj->next) {
+ objlist_push_tail(&list_main, obj);
+ obj->refcount++;
+ }
+
+ if (ld_tracing) { /* We're done */
+ trace_loaded_objects(obj_main);
+ exit(0);
+ }
+
+ if (getenv(LD_ "DUMP_REL_PRE") != NULL) {
+ dump_relocations(obj_main);
+ exit (0);
+ }
+
+ /* setup TLS for main thread */
+ dbg("initializing initial thread local storage");
+ STAILQ_FOREACH(entry, &list_main, link) {
+ /*
+ * Allocate all the initial objects out of the static TLS
+ * block even if they didn't ask for it.
+ */
+ allocate_tls_offset(entry->obj);
+ }
+ allocate_initial_tls(obj_list);
+
+ if (relocate_objects(obj_main,
+ ld_bind_now != NULL && *ld_bind_now != '\0', &obj_rtld) == -1)
+ die();
+
+ dbg("doing copy relocations");
+ if (do_copy_relocations(obj_main) == -1)
+ die();
+
+ if (getenv(LD_ "DUMP_REL_POST") != NULL) {
+ dump_relocations(obj_main);
+ exit (0);
+ }
+
+ dbg("initializing key program variables");
+ set_program_var("__progname", argv[0] != NULL ? basename(argv[0]) : "");
+ set_program_var("environ", env);
+
+ dbg("initializing thread locks");
+ lockdflt_init();
+
+ /* Make a list of init functions to call. */
+ objlist_init(&initlist);
+ initlist_add_objects(obj_list, preload_tail, &initlist);
+
+ r_debug_state(NULL, &obj_main->linkmap); /* say hello to gdb! */
+
+ objlist_call_init(&initlist);
+ lockstate = wlock_acquire(rtld_bind_lock);
+ objlist_clear(&initlist);
+ wlock_release(rtld_bind_lock, lockstate);
+
+ dbg("transferring control to program entry point = %p", obj_main->entry);
+
+ /* Return the exit procedure and the program entry point. */
+ *exit_proc = rtld_exit;
+ *objp = obj_main;
+ return (func_ptr_type) obj_main->entry;
+}
+
+#endif /* 0 */
+
+Elf_Addr
+_rtld_bind(Obj_Entry *obj, Elf_Word reloff)
+{
+ const Elf_Rel *rel;
+ const Elf_Sym *def;
+ const Obj_Entry *defobj;
+ Elf_Addr *where;
+ Elf_Addr target;
+ int lockstate;
+
+ lockstate = rlock_acquire(rtld_bind_lock);
+ if (obj->pltrel)
+ rel = (const Elf_Rel *) ((caddr_t) obj->pltrel + reloff);
+ else
+ rel = (const Elf_Rel *) ((caddr_t) obj->pltrela + reloff);
+
+ where = (Elf_Addr *) (obj->relocbase + rel->r_offset);
+ def = find_symdef(ELF_R_SYM(rel->r_info), obj, &defobj, true, NULL);
+ if (def == NULL)
+ die();
+
+ target = (Elf_Addr)(defobj->relocbase + def->st_value);
+
+ dbg("\"%s\" in \"%s\" ==> %p in \"%s\"",
+ defobj->strtab + def->st_name, basename(obj->path),
+ (void *)target, basename(defobj->path));
+
+ /*
+ * Write the new contents for the jmpslot. Note that depending on
+ * architecture, the value which we need to return back to the
+ * lazy binding trampoline may or may not be the target
+ * address. The value returned from reloc_jmpslot() is the value
+ * that the trampoline needs.
+ */
+ target = reloc_jmpslot(where, target, defobj, obj, rel);
+ rlock_release(rtld_bind_lock, lockstate);
+ return target;
+}
+
+#if 0
+
+/*
+ * Error reporting function. Use it like printf. If formats the message
+ * into a buffer, and sets things up so that the next call to dlerror()
+ * will return the message.
+ */
+void
+_rtld_error(const char *fmt, ...)
+{
+ static char buf[512];
+ va_list ap;
+
+ va_start(ap, fmt);
+ vsnprintf(buf, sizeof buf, fmt, ap);
+ error_message = buf;
+ va_end(ap);
+}
+
+/*
+ * Return a dynamically-allocated copy of the current error message, if any.
+ */
+static char *
+errmsg_save(void)
+{
+ return error_message == NULL ? NULL : xstrdup(error_message);
+}
+
+/*
+ * Restore the current error message from a copy which was previously saved
+ * by errmsg_save(). The copy is freed.
+ */
+static void
+errmsg_restore(char *saved_msg)
+{
+ if (saved_msg == NULL)
+ error_message = NULL;
+ else {
+ _rtld_error("%s", saved_msg);
+ free(saved_msg);
+ }
+}
+
+static const char *
+basename(const char *name)
+{
+ const char *p = strrchr(name, '/');
+ return p != NULL ? p + 1 : name;
+}
+
+static void
+die(void)
+{
+ const char *msg = dlerror();
+
+ if (msg == NULL)
+ msg = "Fatal error";
+ errx(1, "%s", msg);
+}
+
+#endif /* 0 */
+
+/*
+ * Process a shared object's DYNAMIC section, and save the important
+ * information in its Obj_Entry structure.
+ */
+static void
+digest_dynamic(Obj_Entry *obj, int early)
+{
+ const Elf_Dyn *dynp;
+ Needed_Entry **needed_tail = &obj->needed;
+ const Elf_Dyn *dyn_rpath = NULL;
+ int plttype = DT_REL;
+
+ obj->bind_now = false;
+ for (dynp = obj->dynamic; dynp->d_tag != DT_NULL; dynp++) {
+ switch (dynp->d_tag) {
+
+ case DT_REL:
+ obj->rel = (const Elf_Rel *) (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_RELSZ:
+ obj->relsize = dynp->d_un.d_val;
+ break;
+
+ case DT_RELENT:
+ assert(dynp->d_un.d_val == sizeof(Elf_Rel));
+ break;
+
+ case DT_JMPREL:
+ obj->pltrel = (const Elf_Rel *)
+ (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_PLTRELSZ:
+ obj->pltrelsize = dynp->d_un.d_val;
+ break;
+
+ case DT_RELA:
+ obj->rela = (const Elf_Rela *) (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_RELASZ:
+ obj->relasize = dynp->d_un.d_val;
+ break;
+
+ case DT_RELAENT:
+ assert(dynp->d_un.d_val == sizeof(Elf_Rela));
+ break;
+
+ case DT_PLTREL:
+ plttype = dynp->d_un.d_val;
+ assert(dynp->d_un.d_val == DT_REL || plttype == DT_RELA);
+ break;
+
+ case DT_SYMTAB:
+ obj->symtab = (const Elf_Sym *)
+ (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_SYMENT:
+ assert(dynp->d_un.d_val == sizeof(Elf_Sym));
+ break;
+
+ case DT_STRTAB:
+ obj->strtab = (const char *) (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_STRSZ:
+ obj->strsize = dynp->d_un.d_val;
+ break;
+
+ case DT_HASH:
+ {
+ const Elf_Hashelt *hashtab = (const Elf_Hashelt *)
+ (obj->relocbase + dynp->d_un.d_ptr);
+ obj->nbuckets = hashtab[0];
+ obj->nchains = hashtab[1];
+ obj->buckets = hashtab + 2;
+ obj->chains = obj->buckets + obj->nbuckets;
+ }
+ break;
+
+ case DT_NEEDED:
+ if (!obj->rtld) {
+ Needed_Entry *nep = NEW(Needed_Entry);
+ nep->name = dynp->d_un.d_val;
+ nep->obj = NULL;
+ nep->next = NULL;
+
+ *needed_tail = nep;
+ needed_tail = &nep->next;
+ }
+ break;
+
+ case DT_PLTGOT:
+ obj->pltgot = (Elf_Addr *) (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_TEXTREL:
+ obj->textrel = true;
+ break;
+
+ case DT_SYMBOLIC:
+ obj->symbolic = true;
+ break;
+
+ case DT_RPATH:
+ case DT_RUNPATH: /* XXX: process separately */
+ /*
+ * We have to wait until later to process this, because we
+ * might not have gotten the address of the string table yet.
+ */
+ dyn_rpath = dynp;
+ break;
+
+ case DT_SONAME:
+ /* Not used by the dynamic linker. */
+ break;
+
+ case DT_INIT:
+ obj->init = (Elf_Addr) (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_FINI:
+ obj->fini = (Elf_Addr) (obj->relocbase + dynp->d_un.d_ptr);
+ break;
+
+ case DT_DEBUG:
+ /* XXX - not implemented yet */
+ if (!early)
+ dbg("Filling in DT_DEBUG entry");
+ ((Elf_Dyn*)dynp)->d_un.d_ptr = (Elf_Addr) &r_debug;
+ break;
+
+ case DT_FLAGS:
+ if (dynp->d_un.d_val & DF_ORIGIN) {
+ obj->origin_path = xmalloc(PATH_MAX);
+ if (rtld_dirname(obj->path, obj->origin_path) == -1)
+ die();
+ }
+ if (dynp->d_un.d_val & DF_SYMBOLIC)
+ obj->symbolic = true;
+ if (dynp->d_un.d_val & DF_TEXTREL)
+ obj->textrel = true;
+ if (dynp->d_un.d_val & DF_BIND_NOW)
+ obj->bind_now = true;
+ if (dynp->d_un.d_val & DF_STATIC_TLS)
+ ;
+ break;
+
+ default:
+ if (!early) {
+ dbg("Ignoring d_tag %ld = %#lx", (long)dynp->d_tag,
+ (long)dynp->d_tag);
+ }
+ break;
+ }
+ }
+
+ obj->traced = false;
+
+ if (plttype == DT_RELA) {
+ obj->pltrela = (const Elf_Rela *) obj->pltrel;
+ obj->pltrel = NULL;
+ obj->pltrelasize = obj->pltrelsize;
+ obj->pltrelsize = 0;
+ }
+
+ if (dyn_rpath != NULL)
+ obj->rpath = obj->strtab + dyn_rpath->d_un.d_val;
+}
+
+/*
+ * Process a shared object's program header. This is used only for the
+ * main program, when the kernel has already loaded the main program
+ * into memory before calling the dynamic linker. It creates and
+ * returns an Obj_Entry structure.
+ */
+static Obj_Entry *
+digest_phdr(const Elf_Phdr *phdr, int phnum, caddr_t entry, const char *path)
+{
+ Obj_Entry *obj;
+ const Elf_Phdr *phlimit = phdr + phnum;
+ const Elf_Phdr *ph;
+ int nsegs = 0;
+
+ obj = obj_new();
+ for (ph = phdr; ph < phlimit; ph++) {
+ switch (ph->p_type) {
+
+ case PT_PHDR:
+ if ((const Elf_Phdr *)ph->p_vaddr != phdr) {
+ _rtld_error("%s: invalid PT_PHDR", path);
+ return NULL;
+ }
+ obj->phdr = (const Elf_Phdr *) ph->p_vaddr;
+ obj->phsize = ph->p_memsz;
+ break;
+
+ case PT_INTERP:
+ obj->interp = (const char *) ph->p_vaddr;
+ break;
+
+ case PT_LOAD:
+ if (nsegs == 0) { /* First load segment */
+ obj->vaddrbase = trunc_page(ph->p_vaddr);
+ obj->mapbase = (caddr_t) obj->vaddrbase;
+ obj->relocbase = obj->mapbase - obj->vaddrbase;
+ obj->textsize = round_page(ph->p_vaddr + ph->p_memsz) -
+ obj->vaddrbase;
+ } else { /* Last load segment */
+ obj->mapsize = round_page(ph->p_vaddr + ph->p_memsz) -
+ obj->vaddrbase;
+ }
+ nsegs++;
+ break;
+
+ case PT_DYNAMIC:
+ obj->dynamic = (const Elf_Dyn *) ph->p_vaddr;
+ break;
+
+ case PT_TLS:
+ obj->tlsindex = 1;
+ obj->tlssize = ph->p_memsz;
+ obj->tlsalign = ph->p_align;
+ obj->tlsinitsize = ph->p_filesz;
+ obj->tlsinit = (void*) ph->p_vaddr;
+ break;
+ }
+ }
+ if (nsegs < 1) {
+ _rtld_error("%s: too few PT_LOAD segments", path);
+ return NULL;
+ }
+
+ obj->entry = entry;
+ return obj;
+}
+
+#if 0
+
+static Obj_Entry *
+dlcheck(void *handle)
+{
+ Obj_Entry *obj;
+
+ for (obj = obj_list; obj != NULL; obj = obj->next)
+ if (obj == (Obj_Entry *) handle)
+ break;
+
+ if (obj == NULL || obj->refcount == 0 || obj->dl_refcount == 0) {
+ _rtld_error("Invalid shared object handle %p", handle);
+ return NULL;
+ }
+ return obj;
+}
+
+/*
+ * If the given object is already in the donelist, return true. Otherwise
+ * add the object to the list and return false.
+ */
+static bool
+donelist_check(DoneList *dlp, const Obj_Entry *obj)
+{
+ unsigned int i;
+
+ for (i = 0; i < dlp->num_used; i++)
+ if (dlp->objs[i] == obj)
+ return true;
+ /*
+ * Our donelist allocation should always be sufficient. But if
+ * our threads locking isn't working properly, more shared objects
+ * could have been loaded since we allocated the list. That should
+ * never happen, but we'll handle it properly just in case it does.
+ */
+ if (dlp->num_used < dlp->num_alloc)
+ dlp->objs[dlp->num_used++] = obj;
+ return false;
+}
+
+#endif /* 0 */
+
+/*
+ * Hash function for symbol table lookup. Don't even think about changing
+ * this. It is specified by the System V ABI.
+ */
+unsigned long
+elf_hash(const char *name)
+{
+ const unsigned char *p = (const unsigned char *) name;
+ unsigned long h = 0;
+ unsigned long g;
+
+ while (*p != '\0') {
+ h = (h << 4) + *p++;
+ if ((g = h & 0xf0000000) != 0)
+ h ^= g >> 24;
+ h &= ~g;
+ }
+ return h;
+}
+
+#if 0
+
+/*
+ * Find the library with the given name, and return its full pathname.
+ * The returned string is dynamically allocated. Generates an error
+ * message and returns NULL if the library cannot be found.
+ *
+ * If the second argument is non-NULL, then it refers to an already-
+ * loaded shared object, whose library search path will be searched.
+ *
+ * The search order is:
+ * LD_LIBRARY_PATH
+ * rpath in the referencing file
+ * ldconfig hints
+ * /lib:/usr/lib
+ */
+static char *
+find_library(const char *xname, const Obj_Entry *refobj)
+{
+ char *pathname;
+ char *name;
+
+ if (strchr(xname, '/') != NULL) { /* Hard coded pathname */
+ if (xname[0] != '/' && !trust) {
+ _rtld_error("Absolute pathname required for shared object \"%s\"",
+ xname);
+ return NULL;
+ }
+ return xstrdup(xname);
+ }
+
+ if (libmap_disable || (refobj == NULL) ||
+ (name = lm_find(refobj->path, xname)) == NULL)
+ name = (char *)xname;
+
+ dbg(" Searching for \"%s\"", name);
+
+ if ((pathname = search_library_path(name, ld_library_path)) != NULL ||
+ (refobj != NULL &&
+ (pathname = search_library_path(name, refobj->rpath)) != NULL) ||
+ (pathname = search_library_path(name, gethints())) != NULL ||
+ (pathname = search_library_path(name, STANDARD_LIBRARY_PATH)) != NULL)
+ return pathname;
+
+ if(refobj != NULL && refobj->path != NULL) {
+ _rtld_error("Shared object \"%s\" not found, required by \"%s\"",
+ name, basename(refobj->path));
+ } else {
+ _rtld_error("Shared object \"%s\" not found", name);
+ }
+ return NULL;
+}
+
+#endif /* 0 */
+
+/*
+ * Given a symbol number in a referencing object, find the corresponding
+ * definition of the symbol. Returns a pointer to the symbol, or NULL if
+ * no definition was found. Returns a pointer to the Obj_Entry of the
+ * defining object via the reference parameter DEFOBJ_OUT.
+ */
+const Elf_Sym *
+find_symdef(unsigned long symnum, const Obj_Entry *refobj,
+ const Obj_Entry **defobj_out, bool in_plt, SymCache *cache)
+{
+ const Elf_Sym *ref;
+ const Elf_Sym *def;
+ const Obj_Entry *defobj;
+ const char *name;
+ unsigned long hash;
+
+ /*
+ * If we have already found this symbol, get the information from
+ * the cache.
+ */
+ if (symnum >= refobj->nchains)
+ return NULL; /* Bad object */
+ if (cache != NULL && cache[symnum].sym != NULL) {
+ *defobj_out = cache[symnum].obj;
+ return cache[symnum].sym;
+ }
+
+ ref = refobj->symtab + symnum;
+ name = refobj->strtab + ref->st_name;
+ defobj = NULL;
+
+ /*
+ * We don't have to do a full scale lookup if the symbol is local.
+ * We know it will bind to the instance in this load module; to
+ * which we already have a pointer (ie ref). By not doing a lookup,
+ * we not only improve performance, but it also avoids unresolvable
+ * symbols when local symbols are not in the hash table. This has
+ * been seen with the ia64 toolchain.
+ */
+ if (ELF_ST_BIND(ref->st_info) != STB_LOCAL) {
+ if (ELF_ST_TYPE(ref->st_info) == STT_SECTION) {
+ _rtld_error("%s: Bogus symbol table entry %lu", refobj->path,
+ symnum);
+ }
+ hash = elf_hash(name);
+ def = symlook_default(name, hash, refobj, &defobj, in_plt);
+ } else {
+ def = ref;
+ defobj = refobj;
+ }
+
+ /*
+ * If we found no definition and the reference is weak, treat the
+ * symbol as having the value zero.
+ */
+ if (def == NULL && ELF_ST_BIND(ref->st_info) == STB_WEAK) {
+ def = &sym_zero;
+ defobj = obj_main;
+ }
+
+ if (def != NULL) {
+ *defobj_out = defobj;
+ /* Record the information in the cache to avoid subsequent lookups. */
+ if (cache != NULL) {
+ cache[symnum].sym = def;
+ cache[symnum].obj = defobj;
+ }
+ } else {
+ if (refobj != &obj_rtld)
+ _rtld_error("%s: Undefined symbol \"%s\"", refobj->path, name);
+ }
+ return def;
+}
+
+#if 0
+
+/*
+ * Return the search path from the ldconfig hints file, reading it if
+ * necessary. Returns NULL if there are problems with the hints file,
+ * or if the search path there is empty.
+ */
+static const char *
+gethints(void)
+{
+ static char *hints;
+
+ if (hints == NULL) {
+ int fd;
+ struct elfhints_hdr hdr;
+ char *p;
+
+ /* Keep from trying again in case the hints file is bad. */
+ hints = "";
+
+ if ((fd = open(_PATH_ELF_HINTS, O_RDONLY)) == -1)
+ return NULL;
+ if (read(fd, &hdr, sizeof hdr) != sizeof hdr ||
+ hdr.magic != ELFHINTS_MAGIC ||
+ hdr.version != 1) {
+ close(fd);
+ return NULL;
+ }
+ p = xmalloc(hdr.dirlistlen + 1);
+ if (lseek(fd, hdr.strtab + hdr.dirlist, SEEK_SET) == -1 ||
+ read(fd, p, hdr.dirlistlen + 1) != (ssize_t)hdr.dirlistlen + 1) {
+ free(p);
+ close(fd);
+ return NULL;
+ }
+ hints = p;
+ close(fd);
+ }
+ return hints[0] != '\0' ? hints : NULL;
+}
+
+static void
+init_dag(Obj_Entry *root)
+{
+ DoneList donelist;
+
+ donelist_init(&donelist);
+ init_dag1(root, root, &donelist);
+}
+
+static void
+init_dag1(Obj_Entry *root, Obj_Entry *obj, DoneList *dlp)
+{
+ const Needed_Entry *needed;
+
+ if (donelist_check(dlp, obj))
+ return;
+
+ obj->refcount++;
+ objlist_push_tail(&obj->dldags, root);
+ objlist_push_tail(&root->dagmembers, obj);
+ for (needed = obj->needed; needed != NULL; needed = needed->next)
+ if (needed->obj != NULL)
+ init_dag1(root, needed->obj, dlp);
+}
+
+/*
+ * Initialize the dynamic linker. The argument is the address at which
+ * the dynamic linker has been mapped into memory. The primary task of
+ * this function is to relocate the dynamic linker.
+ */
+static void
+init_rtld(caddr_t mapbase)
+{
+ Obj_Entry objtmp; /* Temporary rtld object */
+
+ /*
+ * Conjure up an Obj_Entry structure for the dynamic linker.
+ *
+ * The "path" member can't be initialized yet because string constatns
+ * cannot yet be acessed. Below we will set it correctly.
+ */
+ memset(&objtmp, 0, sizeof(objtmp));
+ objtmp.path = NULL;
+ objtmp.rtld = true;
+ objtmp.mapbase = mapbase;
+#ifdef PIC
+ objtmp.relocbase = mapbase;
+#endif
+ if (RTLD_IS_DYNAMIC()) {
+ objtmp.dynamic = rtld_dynamic(&objtmp);
+ digest_dynamic(&objtmp, 1);
+ assert(objtmp.needed == NULL);
+ assert(!objtmp.textrel);
+
+ /*
+ * Temporarily put the dynamic linker entry into the object list, so
+ * that symbols can be found.
+ */
+
+ relocate_objects(&objtmp, true, &objtmp);
+ }
+
+ /* Initialize the object list. */
+ obj_tail = &obj_list;
+
+ /* Now that non-local variables can be accesses, copy out obj_rtld. */
+ memcpy(&obj_rtld, &objtmp, sizeof(obj_rtld));
+
+ /* Replace the path with a dynamically allocated copy. */
+ obj_rtld.path = xstrdup(PATH_RTLD);
+
+ r_debug.r_brk = r_debug_state;
+ r_debug.r_state = RT_CONSISTENT;
+}
+
+/*
+ * Add the init functions from a needed object list (and its recursive
+ * needed objects) to "list". This is not used directly; it is a helper
+ * function for initlist_add_objects(). The write lock must be held
+ * when this function is called.
+ */
+static void
+initlist_add_neededs(Needed_Entry *needed, Objlist *list)
+{
+ /* Recursively process the successor needed objects. */
+ if (needed->next != NULL)
+ initlist_add_neededs(needed->next, list);
+
+ /* Process the current needed object. */
+ if (needed->obj != NULL)
+ initlist_add_objects(needed->obj, &needed->obj->next, list);
+}
+
+/*
+ * Scan all of the DAGs rooted in the range of objects from "obj" to
+ * "tail" and add their init functions to "list". This recurses over
+ * the DAGs and ensure the proper init ordering such that each object's
+ * needed libraries are initialized before the object itself. At the
+ * same time, this function adds the objects to the global finalization
+ * list "list_fini" in the opposite order. The write lock must be
+ * held when this function is called.
+ */
+static void
+initlist_add_objects(Obj_Entry *obj, Obj_Entry **tail, Objlist *list)
+{
+ if (obj->init_done)
+ return;
+ obj->init_done = true;
+
+ /* Recursively process the successor objects. */
+ if (&obj->next != tail)
+ initlist_add_objects(obj->next, tail, list);
+
+ /* Recursively process the needed objects. */
+ if (obj->needed != NULL)
+ initlist_add_neededs(obj->needed, list);
+
+ /* Add the object to the init list. */
+ if (obj->init != (Elf_Addr)NULL)
+ objlist_push_tail(list, obj);
+
+ /* Add the object to the global fini list in the reverse order. */
+ if (obj->fini != (Elf_Addr)NULL)
+ objlist_push_head(&list_fini, obj);
+}
+
+#ifndef FPTR_TARGET
+#define FPTR_TARGET(f) ((Elf_Addr) (f))
+#endif
+
+static bool
+is_exported(const Elf_Sym *def)
+{
+ Elf_Addr value;
+ const func_ptr_type *p;
+
+ value = (Elf_Addr)(obj_rtld.relocbase + def->st_value);
+ for (p = exports; *p != NULL; p++)
+ if (FPTR_TARGET(*p) == value)
+ return true;
+ return false;
+}
+
+/*
+ * Given a shared object, traverse its list of needed objects, and load
+ * each of them. Returns 0 on success. Generates an error message and
+ * returns -1 on failure.
+ */
+static int
+load_needed_objects(Obj_Entry *first)
+{
+ Obj_Entry *obj;
+
+ for (obj = first; obj != NULL; obj = obj->next) {
+ Needed_Entry *needed;
+
+ for (needed = obj->needed; needed != NULL; needed = needed->next) {
+ const char *name = obj->strtab + needed->name;
+ char *path = find_library(name, obj);
+
+ needed->obj = NULL;
+ if (path == NULL && !ld_tracing)
+ return -1;
+
+ if (path) {
+ needed->obj = load_object(path);
+ if (needed->obj == NULL && !ld_tracing)
+ return -1; /* XXX - cleanup */
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int
+load_preload_objects(void)
+{
+ char *p = ld_preload;
+ static const char delim[] = " \t:;";
+
+ if (p == NULL)
+ return 0;
+
+ p += strspn(p, delim);
+ while (*p != '\0') {
+ size_t len = strcspn(p, delim);
+ char *path;
+ char savech;
+
+ savech = p[len];
+ p[len] = '\0';
+ if ((path = find_library(p, NULL)) == NULL)
+ return -1;
+ if (load_object(path) == NULL)
+ return -1; /* XXX - cleanup */
+ p[len] = savech;
+ p += len;
+ p += strspn(p, delim);
+ }
+ return 0;
+}
+
+/*
+ * Load a shared object into memory, if it is not already loaded. The
+ * argument must be a string allocated on the heap. This function assumes
+ * responsibility for freeing it when necessary.
+ *
+ * Returns a pointer to the Obj_Entry for the object. Returns NULL
+ * on failure.
+ */
+static Obj_Entry *
+load_object(char *path)
+{
+ Obj_Entry *obj;
+ int fd = -1;
+ struct stat sb;
+
+ for (obj = obj_list->next; obj != NULL; obj = obj->next)
+ if (strcmp(obj->path, path) == 0)
+ break;
+
+ /*
+ * If we didn't find a match by pathname, open the file and check
+ * again by device and inode. This avoids false mismatches caused
+ * by multiple links or ".." in pathnames.
+ *
+ * To avoid a race, we open the file and use fstat() rather than
+ * using stat().
+ */
+ if (obj == NULL) {
+ if ((fd = open(path, O_RDONLY)) == -1) {
+ _rtld_error("Cannot open \"%s\"", path);
+ return NULL;
+ }
+ if (fstat(fd, &sb) == -1) {
+ _rtld_error("Cannot fstat \"%s\"", path);
+ close(fd);
+ return NULL;
+ }
+ for (obj = obj_list->next; obj != NULL; obj = obj->next) {
+ if (obj->ino == sb.st_ino && obj->dev == sb.st_dev) {
+ close(fd);
+ break;
+ }
+ }
+ }
+
+ if (obj == NULL) { /* First use of this object, so we must map it in */
+ dbg("loading \"%s\"", path);
+ obj = map_object(fd, path, &sb);
+ close(fd);
+ if (obj == NULL) {
+ free(path);
+ return NULL;
+ }
+
+ obj->path = path;
+ digest_dynamic(obj, 0);
+
+ *obj_tail = obj;
+ obj_tail = &obj->next;
+ obj_count++;
+ linkmap_add(obj); /* for GDB & dlinfo() */
+
+ dbg(" %p .. %p: %s", obj->mapbase,
+ obj->mapbase + obj->mapsize - 1, obj->path);
+ if (obj->textrel)
+ dbg(" WARNING: %s has impure text", obj->path);
+ } else
+ free(path);
+
+ return obj;
+}
+
+static Obj_Entry *
+obj_from_addr(const void *addr)
+{
+ Obj_Entry *obj;
+
+ for (obj = obj_list; obj != NULL; obj = obj->next) {
+ if (addr < (void *) obj->mapbase)
+ continue;
+ if (addr < (void *) (obj->mapbase + obj->mapsize))
+ return obj;
+ }
+ return NULL;
+}
+
+/*
+ * Call the finalization functions for each of the objects in "list"
+ * which are unreferenced. All of the objects are expected to have
+ * non-NULL fini functions.
+ */
+static void
+objlist_call_fini(Objlist *list)
+{
+ Objlist_Entry *elm;
+ char *saved_msg;
+
+ /*
+ * Preserve the current error message since a fini function might
+ * call into the dynamic linker and overwrite it.
+ */
+ saved_msg = errmsg_save();
+ STAILQ_FOREACH(elm, list, link) {
+ if (elm->obj->refcount == 0) {
+ dbg("calling fini function for %s at %p", elm->obj->path,
+ (void *)elm->obj->fini);
+ call_initfini_pointer(elm->obj, elm->obj->fini);
+ }
+ }
+ errmsg_restore(saved_msg);
+}
+
+/*
+ * Call the initialization functions for each of the objects in
+ * "list". All of the objects are expected to have non-NULL init
+ * functions.
+ */
+static void
+objlist_call_init(Objlist *list)
+{
+ Objlist_Entry *elm;
+ char *saved_msg;
+
+ /*
+ * Preserve the current error message since an init function might
+ * call into the dynamic linker and overwrite it.
+ */
+ saved_msg = errmsg_save();
+ STAILQ_FOREACH(elm, list, link) {
+ dbg("calling init function for %s at %p", elm->obj->path,
+ (void *)elm->obj->init);
+ call_initfini_pointer(elm->obj, elm->obj->init);
+ }
+ errmsg_restore(saved_msg);
+}
+
+static void
+objlist_clear(Objlist *list)
+{
+ Objlist_Entry *elm;
+
+ while (!STAILQ_EMPTY(list)) {
+ elm = STAILQ_FIRST(list);
+ STAILQ_REMOVE_HEAD(list, link);
+ free(elm);
+ }
+}
+
+static Objlist_Entry *
+objlist_find(Objlist *list, const Obj_Entry *obj)
+{
+ Objlist_Entry *elm;
+
+ STAILQ_FOREACH(elm, list, link)
+ if (elm->obj == obj)
+ return elm;
+ return NULL;
+}
+
+static void
+objlist_init(Objlist *list)
+{
+ STAILQ_INIT(list);
+}
+
+static void
+objlist_push_head(Objlist *list, Obj_Entry *obj)
+{
+ Objlist_Entry *elm;
+
+ elm = NEW(Objlist_Entry);
+ elm->obj = obj;
+ STAILQ_INSERT_HEAD(list, elm, link);
+}
+
+static void
+objlist_push_tail(Objlist *list, Obj_Entry *obj)
+{
+ Objlist_Entry *elm;
+
+ elm = NEW(Objlist_Entry);
+ elm->obj = obj;
+ STAILQ_INSERT_TAIL(list, elm, link);
+}
+
+static void
+objlist_remove(Objlist *list, Obj_Entry *obj)
+{
+ Objlist_Entry *elm;
+
+ if ((elm = objlist_find(list, obj)) != NULL) {
+ STAILQ_REMOVE(list, elm, Struct_Objlist_Entry, link);
+ free(elm);
+ }
+}
+
+/*
+ * Remove all of the unreferenced objects from "list".
+ */
+static void
+objlist_remove_unref(Objlist *list)
+{
+ Objlist newlist;
+ Objlist_Entry *elm;
+
+ STAILQ_INIT(&newlist);
+ while (!STAILQ_EMPTY(list)) {
+ elm = STAILQ_FIRST(list);
+ STAILQ_REMOVE_HEAD(list, link);
+ if (elm->obj->refcount == 0)
+ free(elm);
+ else
+ STAILQ_INSERT_TAIL(&newlist, elm, link);
+ }
+ *list = newlist;
+}
+
+#endif /* 0 */
+
+/*
+ * Relocate newly-loaded shared objects. The argument is a pointer to
+ * the Obj_Entry for the first such object. All objects from the first
+ * to the end of the list of objects are relocated. Returns 0 on success,
+ * or -1 on failure.
+ */
+static int
+relocate_objects(Obj_Entry *first, bool bind_now, Obj_Entry *rtldobj)
+{
+ Obj_Entry *obj;
+
+ for (obj = first; obj != NULL; obj = obj->next) {
+ if (obj != rtldobj)
+ dbg("relocating \"%s\"", obj->path);
+ if (obj->nbuckets == 0 || obj->nchains == 0 || obj->buckets == NULL ||
+ obj->symtab == NULL || obj->strtab == NULL) {
+ _rtld_error("%s: Shared object has no run-time symbol table",
+ obj->path);
+ return -1;
+ }
+
+ if (obj->textrel) {
+ /* There are relocations to the write-protected text segment. */
+ if (mprotect(obj->mapbase, obj->textsize,
+ PROT_READ|PROT_WRITE|PROT_EXEC) == -1) {
+ _rtld_error("%s: Cannot write-enable text segment: %s",
+ obj->path, strerror(errno));
+ return -1;
+ }
+ }
+
+ /* Process the non-PLT relocations. */
+ if (reloc_non_plt(obj, rtldobj))
+ return -1;
+
+ if (obj->textrel) { /* Re-protected the text segment. */
+ if (mprotect(obj->mapbase, obj->textsize,
+ PROT_READ|PROT_EXEC) == -1) {
+ _rtld_error("%s: Cannot write-protect text segment: %s",
+ obj->path, strerror(errno));
+ return -1;
+ }
+ }
+
+ /* Process the PLT relocations. */
+ if (reloc_plt(obj) == -1)
+ return -1;
+ /* Relocate the jump slots if we are doing immediate binding. */
+ if (obj->bind_now || bind_now)
+ if (reloc_jmpslots(obj) == -1)
+ return -1;
+
+
+ /*
+ * Set up the magic number and version in the Obj_Entry. These
+ * were checked in the crt1.o from the original ElfKit, so we
+ * set them for backward compatibility.
+ */
+ obj->magic = RTLD_MAGIC;
+ obj->version = RTLD_VERSION;
+
+ /* Set the special PLT or GOT entries. */
+ init_pltgot(obj);
+ }
+
+ return 0;
+}
+
+#if 0
+
+/*
+ * Cleanup procedure. It will be called (by the atexit mechanism) just
+ * before the process exits.
+ */
+static void
+rtld_exit(void)
+{
+ Obj_Entry *obj;
+
+ dbg("rtld_exit()");
+ /* Clear all the reference counts so the fini functions will be called. */
+ for (obj = obj_list; obj != NULL; obj = obj->next)
+ obj->refcount = 0;
+ objlist_call_fini(&list_fini);
+ /* No need to remove the items from the list, since we are exiting. */
+ if (!libmap_disable)
+ lm_fini();
+}
+
+static void *
+path_enumerate(const char *path, path_enum_proc callback, void *arg)
+{
+#ifdef COMPAT_32BIT
+ const char *trans;
+#endif
+ if (path == NULL)
+ return (NULL);
+
+ path += strspn(path, ":;");
+ while (*path != '\0') {
+ size_t len;
+ char *res;
+
+ len = strcspn(path, ":;");
+#ifdef COMPAT_32BIT
+ trans = lm_findn(NULL, path, len);
+ if (trans)
+ res = callback(trans, strlen(trans), arg);
+ else
+#endif
+ res = callback(path, len, arg);
+
+ if (res != NULL)
+ return (res);
+
+ path += len;
+ path += strspn(path, ":;");
+ }
+
+ return (NULL);
+}
+
+struct try_library_args {
+ const char *name;
+ size_t namelen;
+ char *buffer;
+ size_t buflen;
+};
+
+static void *
+try_library_path(const char *dir, size_t dirlen, void *param)
+{
+ struct try_library_args *arg;
+
+ arg = param;
+ if (*dir == '/' || trust) {
+ char *pathname;
+
+ if (dirlen + 1 + arg->namelen + 1 > arg->buflen)
+ return (NULL);
+
+ pathname = arg->buffer;
+ strncpy(pathname, dir, dirlen);
+ pathname[dirlen] = '/';
+ strcpy(pathname + dirlen + 1, arg->name);
+
+ dbg(" Trying \"%s\"", pathname);
+ if (access(pathname, F_OK) == 0) { /* We found it */
+ pathname = xmalloc(dirlen + 1 + arg->namelen + 1);
+ strcpy(pathname, arg->buffer);
+ return (pathname);
+ }
+ }
+ return (NULL);
+}
+
+static char *
+search_library_path(const char *name, const char *path)
+{
+ char *p;
+ struct try_library_args arg;
+
+ if (path == NULL)
+ return NULL;
+
+ arg.name = name;
+ arg.namelen = strlen(name);
+ arg.buffer = xmalloc(PATH_MAX);
+ arg.buflen = PATH_MAX;
+
+ p = path_enumerate(path, try_library_path, &arg);
+
+ free(arg.buffer);
+
+ return (p);
+}
+
+int
+dlclose(void *handle)
+{
+ Obj_Entry *root;
+ int lockstate;
+
+ lockstate = wlock_acquire(rtld_bind_lock);
+ root = dlcheck(handle);
+ if (root == NULL) {
+ wlock_release(rtld_bind_lock, lockstate);
+ return -1;
+ }
+
+ /* Unreference the object and its dependencies. */
+ root->dl_refcount--;
+
+ unref_dag(root);
+
+ if (root->refcount == 0) {
+ /*
+ * The object is no longer referenced, so we must unload it.
+ * First, call the fini functions with no locks held.
+ */
+ wlock_release(rtld_bind_lock, lockstate);
+ objlist_call_fini(&list_fini);
+ lockstate = wlock_acquire(rtld_bind_lock);
+ objlist_remove_unref(&list_fini);
+
+ /* Finish cleaning up the newly-unreferenced objects. */
+ GDB_STATE(RT_DELETE,&root->linkmap);
+ unload_object(root);
+ GDB_STATE(RT_CONSISTENT,NULL);
+ }
+ wlock_release(rtld_bind_lock, lockstate);
+ return 0;
+}
+
+const char *
+dlerror(void)
+{
+ char *msg = error_message;
+ error_message = NULL;
+ return msg;
+}
+
+/*
+ * This function is deprecated and has no effect.
+ */
+void
+dllockinit(void *context,
+ void *(*lock_create)(void *context),
+ void (*rlock_acquire)(void *lock),
+ void (*wlock_acquire)(void *lock),
+ void (*lock_release)(void *lock),
+ void (*lock_destroy)(void *lock),
+ void (*context_destroy)(void *context))
+{
+ static void *cur_context;
+ static void (*cur_context_destroy)(void *);
+
+ /* Just destroy the context from the previous call, if necessary. */
+ if (cur_context_destroy != NULL)
+ cur_context_destroy(cur_context);
+ cur_context = context;
+ cur_context_destroy = context_destroy;
+}
+
+void *
+dlopen(const char *name, int mode)
+{
+ Obj_Entry **old_obj_tail;
+ Obj_Entry *obj;
+ Objlist initlist;
+ int result, lockstate;
+
+ ld_tracing = (mode & RTLD_TRACE) == 0 ? NULL : "1";
+ if (ld_tracing != NULL)
+ environ = (char **)*get_program_var_addr("environ");
+
+ objlist_init(&initlist);
+
+ lockstate = wlock_acquire(rtld_bind_lock);
+ GDB_STATE(RT_ADD,NULL);
+
+ old_obj_tail = obj_tail;
+ obj = NULL;
+ if (name == NULL) {
+ obj = obj_main;
+ obj->refcount++;
+ } else {
+ char *path = find_library(name, obj_main);
+ if (path != NULL)
+ obj = load_object(path);
+ }
+
+ if (obj) {
+ obj->dl_refcount++;
+ if (mode & RTLD_GLOBAL && objlist_find(&list_global, obj) == NULL)
+ objlist_push_tail(&list_global, obj);
+ mode &= RTLD_MODEMASK;
+ if (*old_obj_tail != NULL) { /* We loaded something new. */
+ assert(*old_obj_tail == obj);
+
+ result = load_needed_objects(obj);
+ if (result != -1 && ld_tracing)
+ goto trace;
+
+ if (result == -1 ||
+ (init_dag(obj), relocate_objects(obj, mode == RTLD_NOW,
+ &obj_rtld)) == -1) {
+ obj->dl_refcount--;
+ unref_dag(obj);
+ if (obj->refcount == 0)
+ unload_object(obj);
+ obj = NULL;
+ } else {
+ /* Make list of init functions to call. */
+ initlist_add_objects(obj, &obj->next, &initlist);
+ }
+ } else {
+
+ /* Bump the reference counts for objects on this DAG. */
+ ref_dag(obj);
+
+ if (ld_tracing)
+ goto trace;
+ }
+ }
+
+ GDB_STATE(RT_CONSISTENT,obj ? &obj->linkmap : NULL);
+
+ /* Call the init functions with no locks held. */
+ wlock_release(rtld_bind_lock, lockstate);
+ objlist_call_init(&initlist);
+ lockstate = wlock_acquire(rtld_bind_lock);
+ objlist_clear(&initlist);
+ wlock_release(rtld_bind_lock, lockstate);
+ return obj;
+trace:
+ trace_loaded_objects(obj);
+ wlock_release(rtld_bind_lock, lockstate);
+ exit(0);
+}
+
+void *
+dlsym(void *handle, const char *name)
+{
+ const Obj_Entry *obj;
+ unsigned long hash;
+ const Elf_Sym *def;
+ const Obj_Entry *defobj;
+ int lockstate;
+
+ hash = elf_hash(name);
+ def = NULL;
+ defobj = NULL;
+
+ lockstate = rlock_acquire(rtld_bind_lock);
+ if (handle == NULL || handle == RTLD_NEXT ||
+ handle == RTLD_DEFAULT || handle == RTLD_SELF) {
+ void *retaddr;
+
+ retaddr = __builtin_return_address(0); /* __GNUC__ only */
+ if ((obj = obj_from_addr(retaddr)) == NULL) {
+ _rtld_error("Cannot determine caller's shared object");
+ rlock_release(rtld_bind_lock, lockstate);
+ return NULL;
+ }
+ if (handle == NULL) { /* Just the caller's shared object. */
+ def = symlook_obj(name, hash, obj, true);
+ defobj = obj;
+ } else if (handle == RTLD_NEXT || /* Objects after caller's */
+ handle == RTLD_SELF) { /* ... caller included */
+ if (handle == RTLD_NEXT)
+ obj = obj->next;
+ for (; obj != NULL; obj = obj->next) {
+ if ((def = symlook_obj(name, hash, obj, true)) != NULL) {
+ defobj = obj;
+ break;
+ }
+ }
+ } else {
+ assert(handle == RTLD_DEFAULT);
+ def = symlook_default(name, hash, obj, &defobj, true);
+ }
+ } else {
+ if ((obj = dlcheck(handle)) == NULL) {
+ rlock_release(rtld_bind_lock, lockstate);
+ return NULL;
+ }
+
+ if (obj->mainprog) {
+ DoneList donelist;
+
+ /* Search main program and all libraries loaded by it. */
+ donelist_init(&donelist);
+ def = symlook_list(name, hash, &list_main, &defobj, true,
+ &donelist);
+ } else {
+ /*
+ * XXX - This isn't correct. The search should include the whole
+ * DAG rooted at the given object.
+ */
+ def = symlook_obj(name, hash, obj, true);
+ defobj = obj;
+ }
+ }
+
+ if (def != NULL) {
+ rlock_release(rtld_bind_lock, lockstate);
+
+ /*
+ * The value required by the caller is derived from the value
+ * of the symbol. For the ia64 architecture, we need to
+ * construct a function descriptor which the caller can use to
+ * call the function with the right 'gp' value. For other
+ * architectures and for non-functions, the value is simply
+ * the relocated value of the symbol.
+ */
+ if (ELF_ST_TYPE(def->st_info) == STT_FUNC)
+ return make_function_pointer(def, defobj);
+ else
+ return defobj->relocbase + def->st_value;
+ }
+
+ _rtld_error("Undefined symbol \"%s\"", name);
+ rlock_release(rtld_bind_lock, lockstate);
+ return NULL;
+}
+
+int
+dladdr(const void *addr, Dl_info *info)
+{
+ const Obj_Entry *obj;
+ const Elf_Sym *def;
+ void *symbol_addr;
+ unsigned long symoffset;
+ int lockstate;
+
+ lockstate = rlock_acquire(rtld_bind_lock);
+ obj = obj_from_addr(addr);
+ if (obj == NULL) {
+ _rtld_error("No shared object contains address");
+ rlock_release(rtld_bind_lock, lockstate);
+ return 0;
+ }
+ info->dli_fname = obj->path;
+ info->dli_fbase = obj->mapbase;
+ info->dli_saddr = (void *)0;
+ info->dli_sname = NULL;
+
+ /*
+ * Walk the symbol list looking for the symbol whose address is
+ * closest to the address sent in.
+ */
+ for (symoffset = 0; symoffset < obj->nchains; symoffset++) {
+ def = obj->symtab + symoffset;
+
+ /*
+ * For skip the symbol if st_shndx is either SHN_UNDEF or
+ * SHN_COMMON.
+ */
+ if (def->st_shndx == SHN_UNDEF || def->st_shndx == SHN_COMMON)
+ continue;
+
+ /*
+ * If the symbol is greater than the specified address, or if it
+ * is further away from addr than the current nearest symbol,
+ * then reject it.
+ */
+ symbol_addr = obj->relocbase + def->st_value;
+ if (symbol_addr > addr || symbol_addr < info->dli_saddr)
+ continue;
+
+ /* Update our idea of the nearest symbol. */
+ info->dli_sname = obj->strtab + def->st_name;
+ info->dli_saddr = symbol_addr;
+
+ /* Exact match? */
+ if (info->dli_saddr == addr)
+ break;
+ }
+ rlock_release(rtld_bind_lock, lockstate);
+ return 1;
+}
+
+int
+dlinfo(void *handle, int request, void *p)
+{
+ const Obj_Entry *obj;
+ int error, lockstate;
+
+ lockstate = rlock_acquire(rtld_bind_lock);
+
+ if (handle == NULL || handle == RTLD_SELF) {
+ void *retaddr;
+
+ retaddr = __builtin_return_address(0); /* __GNUC__ only */
+ if ((obj = obj_from_addr(retaddr)) == NULL)
+ _rtld_error("Cannot determine caller's shared object");
+ } else
+ obj = dlcheck(handle);
+
+ if (obj == NULL) {
+ rlock_release(rtld_bind_lock, lockstate);
+ return (-1);
+ }
+
+ error = 0;
+ switch (request) {
+ case RTLD_DI_LINKMAP:
+ *((struct link_map const **)p) = &obj->linkmap;
+ break;
+ case RTLD_DI_ORIGIN:
+ error = rtld_dirname(obj->path, p);
+ break;
+
+ case RTLD_DI_SERINFOSIZE:
+ case RTLD_DI_SERINFO:
+ error = do_search_info(obj, request, (struct dl_serinfo *)p);
+ break;
+
+ default:
+ _rtld_error("Invalid request %d passed to dlinfo()", request);
+ error = -1;
+ }
+
+ rlock_release(rtld_bind_lock, lockstate);
+
+ return (error);
+}
+
+struct fill_search_info_args {
+ int request;
+ unsigned int flags;
+ Dl_serinfo *serinfo;
+ Dl_serpath *serpath;
+ char *strspace;
+};
+
+static void *
+fill_search_info(const char *dir, size_t dirlen, void *param)
+{
+ struct fill_search_info_args *arg;
+
+ arg = param;
+
+ if (arg->request == RTLD_DI_SERINFOSIZE) {
+ arg->serinfo->dls_cnt ++;
+ arg->serinfo->dls_size += dirlen + 1;
+ } else {
+ struct dl_serpath *s_entry;
+
+ s_entry = arg->serpath;
+ s_entry->dls_name = arg->strspace;
+ s_entry->dls_flags = arg->flags;
+
+ strncpy(arg->strspace, dir, dirlen);
+ arg->strspace[dirlen] = '\0';
+
+ arg->strspace += dirlen + 1;
+ arg->serpath++;
+ }
+
+ return (NULL);
+}
+
+static int
+do_search_info(const Obj_Entry *obj, int request, struct dl_serinfo *info)
+{
+ struct dl_serinfo _info;
+ struct fill_search_info_args args;
+
+ args.request = RTLD_DI_SERINFOSIZE;
+ args.serinfo = &_info;
+
+ _info.dls_size = __offsetof(struct dl_serinfo, dls_serpath);
+ _info.dls_cnt = 0;
+
+ path_enumerate(ld_library_path, fill_search_info, &args);
+ path_enumerate(obj->rpath, fill_search_info, &args);
+ path_enumerate(gethints(), fill_search_info, &args);
+ path_enumerate(STANDARD_LIBRARY_PATH, fill_search_info, &args);
+
+
+ if (request == RTLD_DI_SERINFOSIZE) {
+ info->dls_size = _info.dls_size;
+ info->dls_cnt = _info.dls_cnt;
+ return (0);
+ }
+
+ if (info->dls_cnt != _info.dls_cnt || info->dls_size != _info.dls_size) {
+ _rtld_error("Uninitialized Dl_serinfo struct passed to dlinfo()");
+ return (-1);
+ }
+
+ args.request = RTLD_DI_SERINFO;
+ args.serinfo = info;
+ args.serpath = &info->dls_serpath[0];
+ args.strspace = (char *)&info->dls_serpath[_info.dls_cnt];
+
+ args.flags = LA_SER_LIBPATH;
+ if (path_enumerate(ld_library_path, fill_search_info, &args) != NULL)
+ return (-1);
+
+ args.flags = LA_SER_RUNPATH;
+ if (path_enumerate(obj->rpath, fill_search_info, &args) != NULL)
+ return (-1);
+
+ args.flags = LA_SER_CONFIG;
+ if (path_enumerate(gethints(), fill_search_info, &args) != NULL)
+ return (-1);
+
+ args.flags = LA_SER_DEFAULT;
+ if (path_enumerate(STANDARD_LIBRARY_PATH, fill_search_info, &args) != NULL)
+ return (-1);
+ return (0);
+}
+
+static int
+rtld_dirname(const char *path, char *bname)
+{
+ const char *endp;
+
+ /* Empty or NULL string gets treated as "." */
+ if (path == NULL || *path == '\0') {
+ bname[0] = '.';
+ bname[1] = '\0';
+ return (0);
+ }
+
+ /* Strip trailing slashes */
+ endp = path + strlen(path) - 1;
+ while (endp > path && *endp == '/')
+ endp--;
+
+ /* Find the start of the dir */
+ while (endp > path && *endp != '/')
+ endp--;
+
+ /* Either the dir is "/" or there are no slashes */
+ if (endp == path) {
+ bname[0] = *endp == '/' ? '/' : '.';
+ bname[1] = '\0';
+ return (0);
+ } else {
+ do {
+ endp--;
+ } while (endp > path && *endp == '/');
+ }
+
+ if (endp - path + 2 > PATH_MAX)
+ {
+ _rtld_error("Filename is too long: %s", path);
+ return(-1);
+ }
+
+ strncpy(bname, path, endp - path + 1);
+ bname[endp - path + 1] = '\0';
+ return (0);
+}
+
+static void
+linkmap_add(Obj_Entry *obj)
+{
+ struct link_map *l = &obj->linkmap;
+ struct link_map *prev;
+
+ obj->linkmap.l_name = obj->path;
+ obj->linkmap.l_addr = obj->mapbase;
+ obj->linkmap.l_ld = obj->dynamic;
+#ifdef __mips__
+ /* GDB needs load offset on MIPS to use the symbols */
+ obj->linkmap.l_offs = obj->relocbase;
+#endif
+
+ if (r_debug.r_map == NULL) {
+ r_debug.r_map = l;
+ return;
+ }
+
+ /*
+ * Scan to the end of the list, but not past the entry for the
+ * dynamic linker, which we want to keep at the very end.
+ */
+ for (prev = r_debug.r_map;
+ prev->l_next != NULL && prev->l_next != &obj_rtld.linkmap;
+ prev = prev->l_next)
+ ;
+
+ /* Link in the new entry. */
+ l->l_prev = prev;
+ l->l_next = prev->l_next;
+ if (l->l_next != NULL)
+ l->l_next->l_prev = l;
+ prev->l_next = l;
+}
+
+static void
+linkmap_delete(Obj_Entry *obj)
+{
+ struct link_map *l = &obj->linkmap;
+
+ if (l->l_prev == NULL) {
+ if ((r_debug.r_map = l->l_next) != NULL)
+ l->l_next->l_prev = NULL;
+ return;
+ }
+
+ if ((l->l_prev->l_next = l->l_next) != NULL)
+ l->l_next->l_prev = l->l_prev;
+}
+
+/*
+ * Function for the debugger to set a breakpoint on to gain control.
+ *
+ * The two parameters allow the debugger to easily find and determine
+ * what the runtime loader is doing and to whom it is doing it.
+ *
+ * When the loadhook trap is hit (r_debug_state, set at program
+ * initialization), the arguments can be found on the stack:
+ *
+ * +8 struct link_map *m
+ * +4 struct r_debug *rd
+ * +0 RetAddr
+ */
+void
+r_debug_state(struct r_debug* rd, struct link_map *m)
+{
+}
+
+/*
+ * Get address of the pointer variable in the main program.
+ */
+static const void **
+get_program_var_addr(const char *name)
+{
+ const Obj_Entry *obj;
+ unsigned long hash;
+
+ hash = elf_hash(name);
+ for (obj = obj_main; obj != NULL; obj = obj->next) {
+ const Elf_Sym *def;
+
+ if ((def = symlook_obj(name, hash, obj, false)) != NULL) {
+ const void **addr;
+
+ addr = (const void **)(obj->relocbase + def->st_value);
+ return addr;
+ }
+ }
+ return NULL;
+}
+
+/*
+ * Set a pointer variable in the main program to the given value. This
+ * is used to set key variables such as "environ" before any of the
+ * init functions are called.
+ */
+static void
+set_program_var(const char *name, const void *value)
+{
+ const void **addr;
+
+ if ((addr = get_program_var_addr(name)) != NULL) {
+ dbg("\"%s\": *%p <-- %p", name, addr, value);
+ *addr = value;
+ }
+}
+
+/*
+ * Given a symbol name in a referencing object, find the corresponding
+ * definition of the symbol. Returns a pointer to the symbol, or NULL if
+ * no definition was found. Returns a pointer to the Obj_Entry of the
+ * defining object via the reference parameter DEFOBJ_OUT.
+ */
+static const Elf_Sym *
+symlook_default(const char *name, unsigned long hash,
+ const Obj_Entry *refobj, const Obj_Entry **defobj_out, bool in_plt)
+{
+ DoneList donelist;
+ const Elf_Sym *def;
+ const Elf_Sym *symp;
+ const Obj_Entry *obj;
+ const Obj_Entry *defobj;
+ const Objlist_Entry *elm;
+ def = NULL;
+ defobj = NULL;
+ donelist_init(&donelist);
+
+ /* Look first in the referencing object if linked symbolically. */
+ if (refobj->symbolic && !donelist_check(&donelist, refobj)) {
+ symp = symlook_obj(name, hash, refobj, in_plt);
+ if (symp != NULL) {
+ def = symp;
+ defobj = refobj;
+ }
+ }
+
+ /* Search all objects loaded at program start up. */
+ if (def == NULL || ELF_ST_BIND(def->st_info) == STB_WEAK) {
+ symp = symlook_list(name, hash, &list_main, &obj, in_plt, &donelist);
+ if (symp != NULL &&
+ (def == NULL || ELF_ST_BIND(symp->st_info) != STB_WEAK)) {
+ def = symp;
+ defobj = obj;
+ }
+ }
+
+ /* Search all DAGs whose roots are RTLD_GLOBAL objects. */
+ STAILQ_FOREACH(elm, &list_global, link) {
+ if (def != NULL && ELF_ST_BIND(def->st_info) != STB_WEAK)
+ break;
+ symp = symlook_list(name, hash, &elm->obj->dagmembers, &obj, in_plt,
+ &donelist);
+ if (symp != NULL &&
+ (def == NULL || ELF_ST_BIND(symp->st_info) != STB_WEAK)) {
+ def = symp;
+ defobj = obj;
+ }
+ }
+
+ /* Search all dlopened DAGs containing the referencing object. */
+ STAILQ_FOREACH(elm, &refobj->dldags, link) {
+ if (def != NULL && ELF_ST_BIND(def->st_info) != STB_WEAK)
+ break;
+ symp = symlook_list(name, hash, &elm->obj->dagmembers, &obj, in_plt,
+ &donelist);
+ if (symp != NULL &&
+ (def == NULL || ELF_ST_BIND(symp->st_info) != STB_WEAK)) {
+ def = symp;
+ defobj = obj;
+ }
+ }
+
+ /*
+ * Search the dynamic linker itself, and possibly resolve the
+ * symbol from there. This is how the application links to
+ * dynamic linker services such as dlopen. Only the values listed
+ * in the "exports" array can be resolved from the dynamic linker.
+ */
+ if (def == NULL || ELF_ST_BIND(def->st_info) == STB_WEAK) {
+ symp = symlook_obj(name, hash, &obj_rtld, in_plt);
+ if (symp != NULL && is_exported(symp)) {
+ def = symp;
+ defobj = &obj_rtld;
+ }
+ }
+
+ if (def != NULL)
+ *defobj_out = defobj;
+ return def;
+}
+
+static const Elf_Sym *
+symlook_list(const char *name, unsigned long hash, Objlist *objlist,
+ const Obj_Entry **defobj_out, bool in_plt, DoneList *dlp)
+{
+ const Elf_Sym *symp;
+ const Elf_Sym *def;
+ const Obj_Entry *defobj;
+ const Objlist_Entry *elm;
+
+ def = NULL;
+ defobj = NULL;
+ STAILQ_FOREACH(elm, objlist, link) {
+ if (donelist_check(dlp, elm->obj))
+ continue;
+ if ((symp = symlook_obj(name, hash, elm->obj, in_plt)) != NULL) {
+ if (def == NULL || ELF_ST_BIND(symp->st_info) != STB_WEAK) {
+ def = symp;
+ defobj = elm->obj;
+ if (ELF_ST_BIND(def->st_info) != STB_WEAK)
+ break;
+ }
+ }
+ }
+ if (def != NULL)
+ *defobj_out = defobj;
+ return def;
+}
+
+#endif /* 0 */
+
+/*
+ * Search the symbol table of a single shared object for a symbol of
+ * the given name. Returns a pointer to the symbol, or NULL if no
+ * definition was found.
+ *
+ * The symbol's hash value is passed in for efficiency reasons; that
+ * eliminates many recomputations of the hash value.
+ */
+const Elf_Sym *
+symlook_obj(const char *name, unsigned long hash, const Obj_Entry *obj,
+ bool in_plt)
+{
+ if (obj->buckets != NULL) {
+ unsigned long symnum = obj->buckets[hash % obj->nbuckets];
+
+ while (symnum != STN_UNDEF) {
+ const Elf_Sym *symp;
+ const char *strp;
+
+ if (symnum >= obj->nchains)
+ return NULL; /* Bad object */
+ symp = obj->symtab + symnum;
+ strp = obj->strtab + symp->st_name;
+
+ if (name[0] == strp[0] && strcmp(name, strp) == 0)
+ return symp->st_shndx != SHN_UNDEF ||
+ (!in_plt && symp->st_value != 0 &&
+ ELF_ST_TYPE(symp->st_info) == STT_FUNC) ? symp : NULL;
+
+ symnum = obj->chains[symnum];
+ }
+ }
+ return NULL;
+}
+
+#if 0
+
+static void
+trace_loaded_objects(Obj_Entry *obj)
+{
+ char *fmt1, *fmt2, *fmt, *main_local, *list_containers;
+ int c;
+
+ if ((main_local = getenv(LD_ "TRACE_LOADED_OBJECTS_PROGNAME")) == NULL)
+ main_local = "";
+
+ if ((fmt1 = getenv(LD_ "TRACE_LOADED_OBJECTS_FMT1")) == NULL)
+ fmt1 = "\t%o => %p (%x)\n";
+
+ if ((fmt2 = getenv(LD_ "TRACE_LOADED_OBJECTS_FMT2")) == NULL)
+ fmt2 = "\t%o (%x)\n";
+
+ list_containers = getenv(LD_ "TRACE_LOADED_OBJECTS_ALL");
+
+ for (; obj; obj = obj->next) {
+ Needed_Entry *needed;
+ char *name, *path;
+ bool is_lib;
+
+ if (list_containers && obj->needed != NULL)
+ printf("%s:\n", obj->path);
+ for (needed = obj->needed; needed; needed = needed->next) {
+ if (needed->obj != NULL) {
+ if (needed->obj->traced && !list_containers)
+ continue;
+ needed->obj->traced = true;
+ path = needed->obj->path;
+ } else
+ path = "not found";
+
+ name = (char *)obj->strtab + needed->name;
+ is_lib = strncmp(name, "lib", 3) == 0; /* XXX - bogus */
+
+ fmt = is_lib ? fmt1 : fmt2;
+ while ((c = *fmt++) != '\0') {
+ switch (c) {
+ default:
+ putchar(c);
+ continue;
+ case '\\':
+ switch (c = *fmt) {
+ case '\0':
+ continue;
+ case 'n':
+ putchar('\n');
+ break;
+ case 't':
+ putchar('\t');
+ break;
+ }
+ break;
+ case '%':
+ switch (c = *fmt) {
+ case '\0':
+ continue;
+ case '%':
+ default:
+ putchar(c);
+ break;
+ case 'A':
+ printf("%s", main_local);
+ break;
+ case 'a':
+ printf("%s", obj_main->path);
+ break;
+ case 'o':
+ printf("%s", name);
+ break;
+#if 0
+ case 'm':
+ printf("%d", sodp->sod_major);
+ break;
+ case 'n':
+ printf("%d", sodp->sod_minor);
+ break;
+#endif
+ case 'p':
+ printf("%s", path);
+ break;
+ case 'x':
+ printf("%p", needed->obj ? needed->obj->mapbase : 0);
+ break;
+ }
+ break;
+ }
+ ++fmt;
+ }
+ }
+ }
+}
+
+/*
+ * Unload a dlopened object and its dependencies from memory and from
+ * our data structures. It is assumed that the DAG rooted in the
+ * object has already been unreferenced, and that the object has a
+ * reference count of 0.
+ */
+static void
+unload_object(Obj_Entry *root)
+{
+ Obj_Entry *obj;
+ Obj_Entry **linkp;
+
+ assert(root->refcount == 0);
+
+ /*
+ * Pass over the DAG removing unreferenced objects from
+ * appropriate lists.
+ */
+ unlink_object(root);
+
+ /* Unmap all objects that are no longer referenced. */
+ linkp = &obj_list->next;
+ while ((obj = *linkp) != NULL) {
+ if (obj->refcount == 0) {
+ dbg("unloading \"%s\"", obj->path);
+ munmap(obj->mapbase, obj->mapsize);
+ linkmap_delete(obj);
+ *linkp = obj->next;
+ obj_count--;
+ obj_free(obj);
+ } else
+ linkp = &obj->next;
+ }
+ obj_tail = linkp;
+}
+
+static void
+unlink_object(Obj_Entry *root)
+{
+ Objlist_Entry *elm;
+
+ if (root->refcount == 0) {
+ /* Remove the object from the RTLD_GLOBAL list. */
+ objlist_remove(&list_global, root);
+
+ /* Remove the object from all objects' DAG lists. */
+ STAILQ_FOREACH(elm, &root->dagmembers , link) {
+ objlist_remove(&elm->obj->dldags, root);
+ if (elm->obj != root)
+ unlink_object(elm->obj);
+ }
+ }
+}
+
+static void
+ref_dag(Obj_Entry *root)
+{
+ Objlist_Entry *elm;
+
+ STAILQ_FOREACH(elm, &root->dagmembers , link)
+ elm->obj->refcount++;
+}
+
+static void
+unref_dag(Obj_Entry *root)
+{
+ Objlist_Entry *elm;
+
+ STAILQ_FOREACH(elm, &root->dagmembers , link)
+ elm->obj->refcount--;
+}
+
+/*
+ * Common code for MD __tls_get_addr().
+ */
+void *
+tls_get_addr_common(Elf_Addr** dtvp, int index, size_t offset)
+{
+ Elf_Addr* dtv = *dtvp;
+
+ /* Check dtv generation in case new modules have arrived */
+ if (dtv[0] != tls_dtv_generation) {
+ Elf_Addr* newdtv;
+ int to_copy;
+
+ newdtv = calloc(1, (tls_max_index + 2) * sizeof(Elf_Addr));
+ to_copy = dtv[1];
+ if (to_copy > tls_max_index)
+ to_copy = tls_max_index;
+ memcpy(&newdtv[2], &dtv[2], to_copy * sizeof(Elf_Addr));
+ newdtv[0] = tls_dtv_generation;
+ newdtv[1] = tls_max_index;
+ free(dtv);
+ *dtvp = newdtv;
+ }
+
+ /* Dynamically allocate module TLS if necessary */
+ if (!dtv[index + 1])
+ dtv[index + 1] = (Elf_Addr)allocate_module_tls(index);
+
+ return (void*) (dtv[index + 1] + offset);
+}
+
+/* XXX not sure what variants to use for arm. */
+
+#if defined(__ia64__) || defined(__alpha__) || defined(__powerpc__)
+
+/*
+ * Allocate Static TLS using the Variant I method.
+ */
+void *
+allocate_tls(Obj_Entry *objs, void *oldtls, size_t tcbsize, size_t tcbalign)
+{
+ Obj_Entry *obj;
+ size_t size;
+ char *tls;
+ Elf_Addr *dtv, *olddtv;
+ Elf_Addr addr;
+ int i;
+
+ size = tls_static_space;
+
+ tls = malloc(size);
+ dtv = malloc((tls_max_index + 2) * sizeof(Elf_Addr));
+
+ *(Elf_Addr**) tls = dtv;
+
+ dtv[0] = tls_dtv_generation;
+ dtv[1] = tls_max_index;
+
+ if (oldtls) {
+ /*
+ * Copy the static TLS block over whole.
+ */
+ memcpy(tls + tcbsize, oldtls + tcbsize, tls_static_space - tcbsize);
+
+ /*
+ * If any dynamic TLS blocks have been created tls_get_addr(),
+ * move them over.
+ */
+ olddtv = *(Elf_Addr**) oldtls;
+ for (i = 0; i < olddtv[1]; i++) {
+ if (olddtv[i+2] < (Elf_Addr)oldtls ||
+ olddtv[i+2] > (Elf_Addr)oldtls + tls_static_space) {
+ dtv[i+2] = olddtv[i+2];
+ olddtv[i+2] = 0;
+ }
+ }
+
+ /*
+ * We assume that all tls blocks are allocated with the same
+ * size and alignment.
+ */
+ free_tls(oldtls, tcbsize, tcbalign);
+ } else {
+ for (obj = objs; obj; obj = obj->next) {
+ if (obj->tlsoffset) {
+ addr = (Elf_Addr)tls + obj->tlsoffset;
+ memset((void*) (addr + obj->tlsinitsize),
+ 0, obj->tlssize - obj->tlsinitsize);
+ if (obj->tlsinit)
+ memcpy((void*) addr, obj->tlsinit,
+ obj->tlsinitsize);
+ dtv[obj->tlsindex + 1] = addr;
+ } else if (obj->tlsindex) {
+ dtv[obj->tlsindex + 1] = 0;
+ }
+ }
+ }
+
+ return tls;
+}
+
+void
+free_tls(void *tls, size_t tcbsize, size_t tcbalign)
+{
+ size_t size;
+ Elf_Addr* dtv;
+ int dtvsize, i;
+ Elf_Addr tlsstart, tlsend;
+
+ /*
+ * Figure out the size of the initial TLS block so that we can
+ * find stuff which __tls_get_addr() allocated dynamically.
+ */
+ size = tls_static_space;
+
+ dtv = ((Elf_Addr**)tls)[0];
+ dtvsize = dtv[1];
+ tlsstart = (Elf_Addr) tls;
+ tlsend = tlsstart + size;
+ for (i = 0; i < dtvsize; i++) {
+ if (dtv[i+2] < tlsstart || dtv[i+2] > tlsend) {
+ free((void*) dtv[i+2]);
+ }
+ }
+
+ free((void*) tlsstart);
+}
+
+#endif
+
+#if defined(__i386__) || defined(__amd64__) || defined(__sparc64__) || \
+ defined(__arm__)
+
+/*
+ * Allocate Static TLS using the Variant II method.
+ */
+void *
+allocate_tls(Obj_Entry *objs, void *oldtls, size_t tcbsize, size_t tcbalign)
+{
+ Obj_Entry *obj;
+ size_t size;
+ char *tls;
+ Elf_Addr *dtv, *olddtv;
+ Elf_Addr segbase, oldsegbase, addr;
+ int i;
+
+ size = round(tls_static_space, tcbalign);
+
+ assert(tcbsize >= 2*sizeof(Elf_Addr));
+ tls = malloc(size + tcbsize);
+ dtv = malloc((tls_max_index + 2) * sizeof(Elf_Addr));
+
+ segbase = (Elf_Addr)(tls + size);
+ ((Elf_Addr*)segbase)[0] = segbase;
+ ((Elf_Addr*)segbase)[1] = (Elf_Addr) dtv;
+
+ dtv[0] = tls_dtv_generation;
+ dtv[1] = tls_max_index;
+
+ if (oldtls) {
+ /*
+ * Copy the static TLS block over whole.
+ */
+ oldsegbase = (Elf_Addr) oldtls;
+ memcpy((void *)(segbase - tls_static_space),
+ (const void *)(oldsegbase - tls_static_space),
+ tls_static_space);
+
+ /*
+ * If any dynamic TLS blocks have been created tls_get_addr(),
+ * move them over.
+ */
+ olddtv = ((Elf_Addr**)oldsegbase)[1];
+ for (i = 0; i < olddtv[1]; i++) {
+ if (olddtv[i+2] < oldsegbase - size || olddtv[i+2] > oldsegbase) {
+ dtv[i+2] = olddtv[i+2];
+ olddtv[i+2] = 0;
+ }
+ }
+
+ /*
+ * We assume that this block was the one we created with
+ * allocate_initial_tls().
+ */
+ free_tls(oldtls, 2*sizeof(Elf_Addr), sizeof(Elf_Addr));
+ } else {
+ for (obj = objs; obj; obj = obj->next) {
+ if (obj->tlsoffset) {
+ addr = segbase - obj->tlsoffset;
+ memset((void*) (addr + obj->tlsinitsize),
+ 0, obj->tlssize - obj->tlsinitsize);
+ if (obj->tlsinit)
+ memcpy((void*) addr, obj->tlsinit, obj->tlsinitsize);
+ dtv[obj->tlsindex + 1] = addr;
+ } else if (obj->tlsindex) {
+ dtv[obj->tlsindex + 1] = 0;
+ }
+ }
+ }
+
+ return (void*) segbase;
+}
+
+void
+free_tls(void *tls, size_t tcbsize, size_t tcbalign)
+{
+ size_t size;
+ Elf_Addr* dtv;
+ int dtvsize, i;
+ Elf_Addr tlsstart, tlsend;
+
+ /*
+ * Figure out the size of the initial TLS block so that we can
+ * find stuff which ___tls_get_addr() allocated dynamically.
+ */
+ size = round(tls_static_space, tcbalign);
+
+ dtv = ((Elf_Addr**)tls)[1];
+ dtvsize = dtv[1];
+ tlsend = (Elf_Addr) tls;
+ tlsstart = tlsend - size;
+ for (i = 0; i < dtvsize; i++) {
+ if (dtv[i+2] < tlsstart || dtv[i+2] > tlsend) {
+ free((void*) dtv[i+2]);
+ }
+ }
+
+ free((void*) tlsstart);
+}
+
+#endif
+
+/*
+ * Allocate TLS block for module with given index.
+ */
+void *
+allocate_module_tls(int index)
+{
+ Obj_Entry* obj;
+ char* p;
+
+ for (obj = obj_list; obj; obj = obj->next) {
+ if (obj->tlsindex == index)
+ break;
+ }
+ if (!obj) {
+ _rtld_error("Can't find module with TLS index %d", index);
+ die();
+ }
+
+ p = malloc(obj->tlssize);
+ memcpy(p, obj->tlsinit, obj->tlsinitsize);
+ memset(p + obj->tlsinitsize, 0, obj->tlssize - obj->tlsinitsize);
+
+ return p;
+}
+
+bool
+allocate_tls_offset(Obj_Entry *obj)
+{
+ size_t off;
+
+ if (obj->tls_done)
+ return true;
+
+ if (obj->tlssize == 0) {
+ obj->tls_done = true;
+ return true;
+ }
+
+ if (obj->tlsindex == 1)
+ off = calculate_first_tls_offset(obj->tlssize, obj->tlsalign);
+ else
+ off = calculate_tls_offset(tls_last_offset, tls_last_size,
+ obj->tlssize, obj->tlsalign);
+
+ /*
+ * If we have already fixed the size of the static TLS block, we
+ * must stay within that size. When allocating the static TLS, we
+ * leave a small amount of space spare to be used for dynamically
+ * loading modules which use static TLS.
+ */
+ if (tls_static_space) {
+ if (calculate_tls_end(off, obj->tlssize) > tls_static_space)
+ return false;
+ }
+
+ tls_last_offset = obj->tlsoffset = off;
+ tls_last_size = obj->tlssize;
+ obj->tls_done = true;
+
+ return true;
+}
+
+void *
+_rtld_allocate_tls(void *oldtls, size_t tcbsize, size_t tcbalign)
+{
+ return allocate_tls(obj_list, oldtls, tcbsize, tcbalign);
+}
+
+void
+_rtld_free_tls(void *tcb, size_t tcbsize, size_t tcbalign)
+{
+ free_tls(tcb, tcbsize, tcbalign);
+}
+
+#endif /* 0 */