freebsd-dev/libexec/rtld-aout/rtld.c
Bruce Evans dd8e0158cf Unmap hints file when finished with it, so that it can go away
completely when ldconfig unlinks it.  If init is shared, then the
referenced unlinked copy of the hints file created by running
ldconfig in /etc/rc caused the file system to be unclean after
every reboot.
1994-09-15 20:48:55 +00:00

1282 lines
28 KiB
C

/*
* Copyright (c) 1993 Paul Kranenburg
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Paul Kranenburg.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* 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.
*
* $Id: rtld.c,v 1.17 1994/06/15 22:41:15 rich Exp $
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/errno.h>
#include <sys/mman.h>
#ifndef BSD
#define MAP_COPY MAP_PRIVATE
#define MAP_ANON 0
#endif
#include <err.h>
#include <fcntl.h>
#include <a.out.h>
#include <stab.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#if __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#include "ld.h"
#ifndef BSD /* Need do better than this */
#define NEED_DEV_ZERO 1
#endif
/*
* Loader private data, hung off <so_map>->som_spd
*/
struct somap_private {
int spd_version;
struct so_map *spd_parent;
int spd_refcount;
int spd_flags;
#define RTLD_MAIN 1
#define RTLD_RTLD 2
#define RTLD_DL 4
#ifdef SUN_COMPAT
long spd_offset; /* Correction for Sun main programs */
#endif
};
#define LM_PRIVATE(smp) ((struct somap_private *)(smp)->som_spd)
#ifdef SUN_COMPAT
#define LM_OFFSET(smp) (LM_PRIVATE(smp)->spd_offset)
#else
#define LM_OFFSET(smp) (0)
#endif
/* Base address for section_dispatch_table entries */
#define LM_LDBASE(smp) (smp->som_addr + LM_OFFSET(smp))
/* Start of text segment */
#define LM_TXTADDR(smp) (smp->som_addr == (caddr_t)0 ? PAGSIZ : 0)
/* Start of run-time relocation_info */
#define LM_REL(smp) ((struct relocation_info *) \
(smp->som_addr + LM_OFFSET(smp) + LD_REL((smp)->som_dynamic)))
/* Start of symbols */
#define LM_SYMBOL(smp, i) ((struct nzlist *) \
(smp->som_addr + LM_OFFSET(smp) + LD_SYMBOL((smp)->som_dynamic) + \
i * (LD_VERSION_NZLIST_P(smp->som_dynamic->d_version) ? \
sizeof(struct nzlist) : sizeof(struct nlist))))
/* Start of hash table */
#define LM_HASH(smp) ((struct rrs_hash *) \
((smp)->som_addr + LM_OFFSET(smp) + LD_HASH((smp)->som_dynamic)))
/* Start of strings */
#define LM_STRINGS(smp) ((char *) \
((smp)->som_addr + LM_OFFSET(smp) + LD_STRINGS((smp)->som_dynamic)))
/* End of text */
#define LM_ETEXT(smp) ((char *) \
((smp)->som_addr + LM_TXTADDR(smp) + LD_TEXTSZ((smp)->som_dynamic)))
/* PLT is in data segment, so don't use LM_OFFSET here */
#define LM_PLT(smp) ((jmpslot_t *) \
((smp)->som_addr + LD_PLT((smp)->som_dynamic)))
/* Parent of link map */
#define LM_PARENT(smp) (LM_PRIVATE(smp)->spd_parent)
char **environ;
char *__progname;
int errno;
static uid_t uid, euid;
static gid_t gid, egid;
static int careful;
static char __main_progname[] = "main";
static char *main_progname = __main_progname;
static char us[] = "/usr/libexec/ld.so";
struct so_map *link_map_head, *main_map;
struct so_map **link_map_tail = &link_map_head;
struct rt_symbol *rt_symbol_head;
static void *__dlopen __P((char *, int));
static int __dlclose __P((void *));
static void *__dlsym __P((void *, char *));
static int __dlctl __P((void *, int, void *));
static struct ld_entry ld_entry = {
__dlopen, __dlclose, __dlsym, __dlctl
};
void xprintf __P((char *, ...));
static void load_objects __P(( struct crt_ldso *,
struct _dynamic *));
static struct so_map *map_object __P((struct sod *, struct so_map *));
static struct so_map *alloc_link_map __P(( char *, struct sod *,
struct so_map *, caddr_t,
struct _dynamic *));
static inline void check_text_reloc __P(( struct relocation_info *,
struct so_map *,
caddr_t));
static void reloc_map __P((struct so_map *));
static void reloc_copy __P((struct so_map *));
static void init_map __P((struct so_map *, char *));
static char *rtfindlib __P((char *, int, int, int *));
void binder_entry __P((void));
long binder __P((jmpslot_t *));
static void unmaphints __P((void));
static struct nzlist *lookup __P((char *, struct so_map **, int));
static inline struct rt_symbol *lookup_rts __P((char *));
static struct rt_symbol *enter_rts __P((char *, long, int, caddr_t,
long, struct so_map *));
static inline int
strcmp (register const char *s1, register const char *s2)
{
while (*s1 == *s2++)
if (*s1++ == 0)
return (0);
return (*(unsigned char *)s1 - *(unsigned char *)--s2);
}
#include "md-static-funcs.c"
/*
* Called from assembler stub that has set up crtp (passed from crt0)
* and dp (our __DYNAMIC).
*/
int
rtld(version, crtp, dp)
int version;
struct crt_ldso *crtp;
struct _dynamic *dp;
{
int n;
int nreloc; /* # of ld.so relocations */
struct relocation_info *reloc;
struct so_debug *ddp;
struct so_map *smp;
/* Check version */
if ( version != CRT_VERSION_BSD_2 &&
version != CRT_VERSION_BSD_3 &&
version != CRT_VERSION_SUN)
return -1;
/* Fixup __DYNAMIC structure */
(long)dp->d_un.d_sdt += crtp->crt_ba;
/* Divide by hand to avoid possible use of library division routine */
for ( nreloc = 0, n = LD_RELSZ(dp);
n > 0;
n -= sizeof(struct relocation_info) ) nreloc++;
/* Relocate ourselves */
for ( reloc = (struct relocation_info *)(LD_REL(dp) + crtp->crt_ba);
nreloc;
nreloc--, reloc++) {
register long addr = reloc->r_address + crtp->crt_ba;
md_relocate_simple(reloc, crtp->crt_ba, addr);
}
__progname = "ld.so";
if (version >= CRT_VERSION_BSD_3)
main_progname = crtp->crt_prog;
/* Setup out (private) environ variable */
environ = crtp->crt_ep;
/* Get user and group identifiers */
uid = getuid(); euid = geteuid();
gid = getgid(); egid = getegid();
careful = (uid != euid) || (gid != egid);
if (careful) {
unsetenv("LD_LIBRARY_PATH");
unsetenv("LD_PRELOAD");
unsetenv("LD_RUN_PATH"); /* In case we ever implement this */
}
/* Setup directory search */
add_search_path(getenv("LD_RUN_PATH"));
add_search_path(getenv("LD_LIBRARY_PATH"));
if (getenv("LD_NOSTD_PATH") == NULL)
std_search_path();
/* Load required objects into the process address space */
load_objects(crtp, dp);
/* Relocate all loaded objects according to their RRS segments */
for (smp = link_map_head; smp; smp = smp->som_next) {
if (LM_PRIVATE(smp)->spd_flags & RTLD_RTLD)
continue;
reloc_map(smp);
}
/* Copy any relocated initialized data. */
for (smp = link_map_head; smp; smp = smp->som_next) {
if (LM_PRIVATE(smp)->spd_flags & RTLD_RTLD)
continue;
reloc_copy(smp);
}
/* Call any object initialization routines. */
for (smp = link_map_head; smp; smp = smp->som_next) {
if (LM_PRIVATE(smp)->spd_flags & RTLD_RTLD)
continue;
init_map(smp, ".init");
}
/* Fill in some field in main's __DYNAMIC structure */
crtp->crt_dp->d_entry = &ld_entry;
crtp->crt_dp->d_un.d_sdt->sdt_loaded = link_map_head->som_next;
ddp = crtp->crt_dp->d_debug;
ddp->dd_cc = rt_symbol_head;
if (ddp->dd_in_debugger) {
caddr_t addr = (caddr_t)((long)crtp->crt_bp & (~(PAGSIZ - 1)));
/* Set breakpoint for the benefit of debuggers */
if (mprotect(addr, PAGSIZ,
PROT_READ|PROT_WRITE|PROT_EXEC) == -1) {
err(1, "Cannot set breakpoint (%s)", main_progname);
}
md_set_breakpoint((long)crtp->crt_bp, (long *)&ddp->dd_bpt_shadow);
if (mprotect(addr, PAGSIZ, PROT_READ|PROT_EXEC) == -1) {
err(1, "Cannot re-protect breakpoint (%s)",
main_progname);
}
ddp->dd_bpt_addr = crtp->crt_bp;
if (link_map_head)
ddp->dd_sym_loaded = 1;
}
/* Forget hints so that hints file can go away if it is unlinked */
unmaphints();
/* Close our file descriptor */
(void)close(crtp->crt_ldfd);
return 0;
}
static void
load_objects(crtp, dp)
struct crt_ldso *crtp;
struct _dynamic *dp;
{
struct so_map *smp;
int tracing = (int)getenv("LD_TRACE_LOADED_OBJECTS");
/* Handle LD_PRELOAD's here */
/* Make an entry for the main program */
smp = alloc_link_map(main_progname, (struct sod *)0, (struct so_map *)0,
(caddr_t)0, crtp->crt_dp);
LM_PRIVATE(smp)->spd_refcount++;
LM_PRIVATE(smp)->spd_flags |= RTLD_MAIN;
/* Make an entry for ourselves */
smp = alloc_link_map(us, (struct sod *)0, (struct so_map *)0,
(caddr_t)crtp->crt_ba, dp);
LM_PRIVATE(smp)->spd_refcount++;
LM_PRIVATE(smp)->spd_flags |= RTLD_RTLD;
for (smp = link_map_head; smp; smp = smp->som_next) {
struct sod *sodp;
long next = 0;
if (LM_PRIVATE(smp)->spd_flags & RTLD_RTLD)
continue;
if (smp->som_dynamic)
next = LD_NEED(smp->som_dynamic);
while (next) {
struct so_map *newmap;
sodp = (struct sod *)(LM_LDBASE(smp) + next);
if ((newmap = map_object(sodp, smp)) == NULL) {
if (!tracing) {
char *name = (char *)
(sodp->sod_name + LM_LDBASE(smp));
char *fmt = sodp->sod_library ?
"%s: lib%s.so.%d.%d" :
"%s: %s";
err(1, fmt, main_progname, name,
sodp->sod_major,
sodp->sod_minor);
}
newmap = alloc_link_map(NULL, sodp, smp, 0, 0);
}
LM_PRIVATE(newmap)->spd_refcount++;
next = sodp->sod_next;
}
}
if (! tracing)
return;
for (smp = link_map_head; smp; smp = smp->som_next) {
struct sod *sodp;
char *name, *path;
if ((sodp = smp->som_sod) == NULL)
continue;
name = sodp->sod_name + LM_LDBASE(LM_PARENT(smp));
if ((path = smp->som_path) == NULL)
path = "not found";
if (sodp->sod_library)
printf("\t-l%s.%d => %s (%p)\n", name,
sodp->sod_major, path, smp->som_addr);
else
printf("\t%s => %s (%p)\n", name, path, smp->som_addr);
}
exit(0);
}
/*
* Allocate a new link map for shared object NAME loaded at ADDR as a
* result of the presence of link object LOP in the link map PARENT.
*/
static struct so_map *
alloc_link_map(path, sodp, parent, addr, dp)
char *path;
struct sod *sodp;
struct so_map *parent;
caddr_t addr;
struct _dynamic *dp;
{
struct so_map *smp;
struct somap_private *smpp;
smpp = (struct somap_private *)xmalloc(sizeof(struct somap_private));
smp = (struct so_map *)xmalloc(sizeof(struct so_map));
smp->som_next = NULL;
*link_map_tail = smp;
link_map_tail = &smp->som_next;
smp->som_addr = addr;
smp->som_path = strdup(path);
smp->som_sod = sodp;
smp->som_dynamic = dp;
smp->som_spd = (caddr_t)smpp;
/*XXX*/ if (addr == 0) main_map = smp;
smpp->spd_refcount = 0;
smpp->spd_flags = 0;
smpp->spd_parent = parent;
#ifdef SUN_COMPAT
smpp->spd_offset =
(addr==0 && dp && dp->d_version==LD_VERSION_SUN) ? PAGSIZ : 0;
#endif
return smp;
}
/*
* Map object identified by link object LOP which was found
* in link map LMP.
*/
static struct so_map *
map_object(sodp, smp)
struct sod *sodp;
struct so_map *smp;
{
struct _dynamic *dp;
char *path, *name = (char *)(sodp->sod_name + LM_LDBASE(smp));
int fd;
caddr_t addr;
struct exec hdr;
int usehints = 0;
struct so_map *p;
if (sodp->sod_library) {
usehints = 1;
again:
path = rtfindlib(name, sodp->sod_major,
sodp->sod_minor, &usehints);
if (path == NULL) {
errno = ENOENT;
return NULL;
}
} else {
if (careful && *name != '/') {
errno = EACCES;
return NULL;
}
path = name;
}
/* Check if already loaded */
for (p = link_map_head; p; p = p->som_next)
if (p->som_path && strcmp(p->som_path, path) == 0)
break;
if (p != NULL)
return p;
if ((fd = open(path, O_RDONLY, 0)) == -1) {
if (usehints) {
usehints = 0;
goto again;
}
return NULL;
}
if (read(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) {
(void)close(fd);
/*errno = x;*/
return NULL;
}
if (N_BADMAG(hdr)) {
(void)close(fd);
errno = EFTYPE;
return NULL;
}
if ((addr = mmap(0, hdr.a_text + hdr.a_data,
PROT_READ|PROT_EXEC,
MAP_FILE|MAP_COPY, fd, 0)) == (caddr_t)-1) {
(void)close(fd);
return NULL;
}
#if 0
if (mmap(addr + hdr.a_text, hdr.a_data,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_FILE|MAP_FIXED|MAP_COPY,
fd, hdr.a_text) == (caddr_t)-1) {
(void)close(fd);
return NULL;
}
#endif
if (mprotect(addr + hdr.a_text, hdr.a_data,
PROT_READ|PROT_WRITE|PROT_EXEC) != 0) {
(void)close(fd);
return NULL;
}
(void)close(fd);
fd = -1;
#ifdef NEED_DEV_ZERO
if ((fd = open("/dev/zero", O_RDWR, 0)) == -1)
warn("open: %s", "/dev/zero");
#endif
if (hdr.a_bss && mmap(addr + hdr.a_text + hdr.a_data, hdr.a_bss,
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_ANON|MAP_FIXED|MAP_COPY,
fd, hdr.a_text + hdr.a_data) == (caddr_t)-1)
return NULL;
#ifdef NEED_DEV_ZERO
close(fd);
#endif
/* Assume _DYNAMIC is the first data item */
dp = (struct _dynamic *)(addr+hdr.a_text);
/* Fixup __DYNAMIC structure */
(long)dp->d_un.d_sdt += (long)addr;
return alloc_link_map(path, sodp, smp, addr, dp);
}
static inline void
check_text_reloc(r, smp, addr)
struct relocation_info *r;
struct so_map *smp;
caddr_t addr;
{
char *sym;
if (addr >= LM_ETEXT(smp))
return;
if (RELOC_EXTERN_P(r))
sym = LM_STRINGS(smp) +
LM_SYMBOL(smp, RELOC_SYMBOL(r))->nz_strx;
else
sym = "";
if (getenv("LD_WARN_NON_PURE_CODE") != NULL)
fprintf(stderr,
"ld.so: warning: non pure code in %s at %x (%s)\n",
smp->som_path, r->r_address, sym);
if (smp->som_write == 0 &&
mprotect(smp->som_addr + LM_TXTADDR(smp),
LD_TEXTSZ(smp->som_dynamic),
PROT_READ|PROT_WRITE|PROT_EXEC) == -1) {
err(1, "Cannot enable writes to %s:%s",
main_progname, smp->som_path);
}
smp->som_write = 1;
}
static void
reloc_map(smp)
struct so_map *smp;
{
struct _dynamic *dp = smp->som_dynamic;
struct relocation_info *r = LM_REL(smp);
struct relocation_info *rend = r + LD_RELSZ(dp)/sizeof(*r);
long symbolbase = (long)LM_SYMBOL(smp, 0);
char *stringbase = LM_STRINGS(smp);
int symsize = LD_VERSION_NZLIST_P(dp->d_version) ?
sizeof(struct nzlist) :
sizeof(struct nlist);
if (LD_PLTSZ(dp))
md_fix_jmpslot(LM_PLT(smp),
(long)LM_PLT(smp), (long)binder_entry);
for (; r < rend; r++) {
char *sym;
caddr_t addr = smp->som_addr + r->r_address;
check_text_reloc(r, smp, addr);
if (RELOC_EXTERN_P(r)) {
struct so_map *src_map = NULL;
struct nzlist *p, *np;
long relocation = md_get_addend(r, addr);
if (RELOC_LAZY_P(r))
continue;
p = (struct nzlist *)
(symbolbase + symsize * RELOC_SYMBOL(r));
if (p->nz_type == (N_SETV + N_EXT))
src_map = smp;
sym = stringbase + p->nz_strx;
np = lookup(sym, &src_map, 0/*XXX-jumpslots!*/);
if (np == NULL)
errx(1, "Undefined symbol \"%s\" in %s:%s\n",
sym, main_progname, smp->som_path);
/*
* Found symbol definition.
* If it's in a link map, adjust value
* according to the load address of that map.
* Otherwise it's a run-time allocated common
* whose value is already up-to-date.
*/
relocation += np->nz_value;
if (src_map)
relocation += (long)src_map->som_addr;
if (RELOC_PCREL_P(r))
relocation -= (long)smp->som_addr;
if (RELOC_COPY_P(r) && src_map) {
(void)enter_rts(sym,
(long)addr,
N_DATA + N_EXT,
src_map->som_addr + np->nz_value,
np->nz_size, src_map);
continue;
}
md_relocate(r, relocation, addr, 0);
} else {
md_relocate(r,
#ifdef SUN_COMPAT
md_get_rt_segment_addend(r, addr)
#else
md_get_addend(r, addr)
#endif
+ (long)smp->som_addr, addr, 0);
}
}
if (smp->som_write) {
if (mprotect(smp->som_addr + LM_TXTADDR(smp),
LD_TEXTSZ(smp->som_dynamic),
PROT_READ|PROT_EXEC) == -1) {
err(1, "Cannot disable writes to %s:%s\n",
main_progname, smp->som_path);
}
smp->som_write = 0;
}
}
static void
reloc_copy(smp)
struct so_map *smp;
{
struct rt_symbol *rtsp;
for (rtsp = rt_symbol_head; rtsp; rtsp = rtsp->rt_next)
if ((rtsp->rt_smp == NULL || rtsp->rt_smp == smp) &&
rtsp->rt_sp->nz_type == N_DATA + N_EXT) {
bcopy(rtsp->rt_srcaddr, (caddr_t)rtsp->rt_sp->nz_value,
rtsp->rt_sp->nz_size);
}
}
static void
init_map(smp, sym)
struct so_map *smp;
char *sym;
{
struct so_map *src_map = smp;
struct nzlist *np;
np = lookup(sym, &src_map, 1);
if (np)
(*(void (*)())(src_map->som_addr + np->nz_value))();
}
/*
* Run-time common symbol table.
*/
#define RTC_TABSIZE 57
static struct rt_symbol *rt_symtab[RTC_TABSIZE];
/*
* Compute hash value for run-time symbol table
*/
static inline int
hash_string(key)
char *key;
{
register char *cp;
register int k;
cp = key;
k = 0;
while (*cp)
k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
return k;
}
/*
* Lookup KEY in the run-time common symbol table.
*/
static inline struct rt_symbol *
lookup_rts(key)
char *key;
{
register int hashval;
register struct rt_symbol *rtsp;
/* Determine which bucket. */
hashval = hash_string(key) % RTC_TABSIZE;
/* Search the bucket. */
for (rtsp = rt_symtab[hashval]; rtsp; rtsp = rtsp->rt_link)
if (strcmp(key, rtsp->rt_sp->nz_name) == 0)
return rtsp;
return NULL;
}
static struct rt_symbol *
enter_rts(name, value, type, srcaddr, size, smp)
char *name;
long value;
int type;
caddr_t srcaddr;
long size;
struct so_map *smp;
{
register int hashval;
register struct rt_symbol *rtsp, **rpp;
/* Determine which bucket */
hashval = hash_string(name) % RTC_TABSIZE;
/* Find end of bucket */
for (rpp = &rt_symtab[hashval]; *rpp; rpp = &(*rpp)->rt_link)
;
/* Allocate new common symbol */
rtsp = (struct rt_symbol *)malloc(sizeof(struct rt_symbol));
rtsp->rt_sp = (struct nzlist *)malloc(sizeof(struct nzlist));
rtsp->rt_sp->nz_name = strdup(name);
rtsp->rt_sp->nz_value = value;
rtsp->rt_sp->nz_type = type;
rtsp->rt_sp->nz_size = size;
rtsp->rt_srcaddr = srcaddr;
rtsp->rt_smp = smp;
rtsp->rt_link = NULL;
/* Link onto linear list as well */
rtsp->rt_next = rt_symbol_head;
rt_symbol_head = rtsp;
*rpp = rtsp;
return rtsp;
}
/*
* Lookup NAME in the link maps. The link map producing a definition
* is returned in SRC_MAP. If SRC_MAP is not NULL on entry the search is
* confined to that map. If STRONG is set, the symbol returned must
* have a proper type (used by binder()).
*/
static struct nzlist *
lookup(name, src_map, strong)
char *name;
struct so_map **src_map; /* IN/OUT */
int strong;
{
long common_size = 0;
struct so_map *smp;
struct rt_symbol *rtsp;
if ((rtsp = lookup_rts(name)) != NULL)
return rtsp->rt_sp;
/*
* Search all maps for a definition of NAME
*/
for (smp = link_map_head; smp; smp = smp->som_next) {
int buckets = LD_BUCKETS(smp->som_dynamic);
long hashval;
struct rrs_hash *hp;
char *cp;
struct nzlist *np;
/* Some local caching */
long symbolbase;
struct rrs_hash *hashbase;
char *stringbase;
int symsize;
if (LM_PRIVATE(smp)->spd_flags & RTLD_RTLD)
continue;
if (*src_map && smp != *src_map)
continue;
restart:
/*
* Compute bucket in which the symbol might be found.
*/
for (hashval = 0, cp = name; *cp; cp++)
hashval = (hashval << 1) + *cp;
hashval = (hashval & 0x7fffffff) % buckets;
hashbase = LM_HASH(smp);
hp = hashbase + hashval;
if (hp->rh_symbolnum == -1)
/* Nothing in this bucket */
continue;
symbolbase = (long)LM_SYMBOL(smp, 0);
stringbase = LM_STRINGS(smp);
symsize = LD_VERSION_NZLIST_P(smp->som_dynamic->d_version)?
sizeof(struct nzlist) :
sizeof(struct nlist);
while (hp) {
np = (struct nzlist *)
(symbolbase + hp->rh_symbolnum * symsize);
cp = stringbase + np->nz_strx;
if (strcmp(cp, name) == 0)
break;
if (hp->rh_next == 0)
hp = NULL;
else
hp = hashbase + hp->rh_next;
}
if (hp == NULL)
/* Nothing in this bucket */
continue;
/*
* We have a symbol with the name we're looking for.
*/
if (np->nz_type == N_INDR+N_EXT) {
/*
* Next symbol gives the aliased name. Restart
* search with new name and confine to this map.
*/
name = stringbase + (++np)->nz_strx;
*src_map = smp;
goto restart;
}
if (np->nz_value == 0)
/* It's not a definition */
continue;
if (np->nz_type == N_UNDF+N_EXT && np->nz_value != 0) {
if (np->nz_other == AUX_FUNC) {
/* It's a weak function definition */
if (strong)
continue;
} else {
/* It's a common, note value and continue search */
if (common_size < np->nz_value)
common_size = np->nz_value;
continue;
}
}
*src_map = smp;
return np;
}
if (common_size == 0)
/* Not found */
return NULL;
/*
* It's a common, enter into run-time common symbol table.
*/
rtsp = enter_rts(name, (long)calloc(1, common_size),
N_UNDF + N_EXT, 0, common_size, NULL);
#if DEBUG
xprintf("Allocating common: %s size %d at %#x\n", name, common_size, rtsp->rt_sp->nz_value);
#endif
return rtsp->rt_sp;
}
/*
* This routine is called from the jumptable to resolve
* procedure calls to shared objects.
*/
long
binder(jsp)
jmpslot_t *jsp;
{
struct so_map *smp, *src_map = NULL;
long addr;
char *sym;
struct nzlist *np;
int index;
/*
* Find the PLT map that contains JSP.
*/
for (smp = link_map_head; smp; smp = smp->som_next) {
if (LM_PLT(smp) < jsp &&
jsp < LM_PLT(smp) + LD_PLTSZ(smp->som_dynamic)/sizeof(*jsp))
break;
}
if (smp == NULL)
errx(1, "Call to binder from unknown location: %#x\n", jsp);
index = jsp->reloc_index & JMPSLOT_RELOC_MASK;
/* Get the local symbol this jmpslot refers to */
sym = LM_STRINGS(smp) +
LM_SYMBOL(smp,RELOC_SYMBOL(&LM_REL(smp)[index]))->nz_strx;
np = lookup(sym, &src_map, 1);
if (np == NULL)
errx(1, "Undefined symbol \"%s\" called from %s:%s at %#x",
sym, main_progname, smp->som_path, jsp);
/* Fixup jmpslot so future calls transfer directly to target */
addr = np->nz_value;
if (src_map)
addr += (long)src_map->som_addr;
md_fix_jmpslot(jsp, (long)jsp, addr);
#if DEBUG
xprintf(" BINDER: %s located at = %#x in %s\n", sym, addr, src_map->som_path);
#endif
return addr;
}
static struct hints_header *hheader;
static long hmsize;
static struct hints_bucket *hbuckets;
static char *hstrtab;
#define HINTS_VALID (hheader != NULL && hheader != (struct hints_header *)-1)
static void
maphints()
{
caddr_t addr;
long msize;
int fd;
if ((fd = open(_PATH_LD_HINTS, O_RDONLY, 0)) == -1) {
hheader = (struct hints_header *)-1;
return;
}
msize = PAGSIZ;
addr = mmap(0, msize, PROT_READ, MAP_FILE|MAP_COPY, fd, 0);
if (addr == (caddr_t)-1) {
close(fd);
hheader = (struct hints_header *)-1;
return;
}
hheader = (struct hints_header *)addr;
if (HH_BADMAG(*hheader)) {
munmap(addr, msize);
close(fd);
hheader = (struct hints_header *)-1;
return;
}
if (hheader->hh_version != LD_HINTS_VERSION_1) {
munmap(addr, msize);
close(fd);
hheader = (struct hints_header *)-1;
return;
}
hmsize = msize;
if (hheader->hh_ehints > msize) {
hmsize = hheader->hh_ehints;
if (mmap(addr+msize, hheader->hh_ehints - msize,
PROT_READ, MAP_FILE|MAP_COPY|MAP_FIXED,
fd, msize) != (caddr_t)(addr+msize)) {
munmap((caddr_t)hheader, msize);
close(fd);
hheader = (struct hints_header *)-1;
return;
}
}
close(fd);
hbuckets = (struct hints_bucket *)(addr + hheader->hh_hashtab);
hstrtab = (char *)(addr + hheader->hh_strtab);
}
static void
unmaphints()
{
if (HINTS_VALID) {
munmap((caddr_t)hheader, hmsize);
hheader = NULL;
}
}
int
hinthash(cp, vmajor, vminor)
char *cp;
int vmajor, vminor;
{
int k = 0;
while (*cp)
k = (((k << 1) + (k >> 14)) ^ (*cp++)) & 0x3fff;
k = (((k << 1) + (k >> 14)) ^ (vmajor*257)) & 0x3fff;
k = (((k << 1) + (k >> 14)) ^ (vminor*167)) & 0x3fff;
return k;
}
#undef major
#undef minor
static char *
findhint(name, major, minor, preferred_path)
char *name;
int major, minor;
char *preferred_path;
{
struct hints_bucket *bp;
bp = hbuckets + (hinthash(name, major, minor) % hheader->hh_nbucket);
while (1) {
/* Sanity check */
if (bp->hi_namex >= hheader->hh_strtab_sz) {
fprintf(stderr, "Bad name index: %#x\n", bp->hi_namex);
break;
}
if (bp->hi_pathx >= hheader->hh_strtab_sz) {
fprintf(stderr, "Bad path index: %#x\n", bp->hi_pathx);
break;
}
if (strcmp(name, hstrtab + bp->hi_namex) == 0) {
/* It's `name', check version numbers */
if (bp->hi_major == major &&
(bp->hi_ndewey < 2 || bp->hi_minor == minor)) {
if (preferred_path == NULL ||
strcmp(preferred_path,
hstrtab + bp->hi_pathx) == 0) {
return hstrtab + bp->hi_pathx;
}
}
}
if (bp->hi_next == -1)
break;
/* Move on to next in bucket */
bp = &hbuckets[bp->hi_next];
}
/* No hints available for name */
return NULL;
}
static char *
rtfindlib(name, major, minor, usehints)
char *name;
int major, minor;
int *usehints;
{
char *hint;
char *cp, *ld_path = getenv("LD_LIBRARY_PATH");
if (hheader == NULL)
maphints();
if (!HINTS_VALID || !(*usehints)) {
*usehints = 0;
return (char *)findshlib(name, &major, &minor, 0);
}
if (ld_path != NULL) {
/* Prefer paths from LD_LIBRARY_PATH */
while ((cp = strsep(&ld_path, ":")) != NULL) {
hint = findhint(name, major, minor, cp);
if (ld_path)
*(ld_path-1) = ':';
if (hint)
return hint;
}
/* Not found in hints, try directory search */
hint = (char *)findshlib(name, &major, &minor, 0);
if (hint)
return hint;
}
/* No LD_LIBRARY_PATH or lib not found in there; check default */
hint = findhint(name, major, minor, NULL);
if (hint)
return hint;
/* No hints available for name */
*usehints = 0;
return (char *)findshlib(name, &major, &minor, 0);
}
static struct somap_private dlmap_private = {
0,
(struct so_map *)0,
0,
#ifdef SUN_COMPAT
0,
#endif
};
static struct so_map dlmap = {
(caddr_t)0,
"internal",
(struct so_map *)0,
(struct sod *)0,
(caddr_t)0,
(u_int)0,
(struct _dynamic *)0,
(caddr_t)&dlmap_private
};
static int dlerrno;
static void *
__dlopen(name, mode)
char *name;
int mode;
{
struct sod *sodp;
struct so_map *smp;
/*
* A NULL argument returns the current set of mapped objects.
*/
if (name == NULL)
return link_map_head;
if ((sodp = (struct sod *)malloc(sizeof(struct sod))) == NULL) {
dlerrno = ENOMEM;
return NULL;
}
sodp->sod_name = (long)strdup(name);
sodp->sod_library = 0;
sodp->sod_major = sodp->sod_minor = 0;
if ((smp = map_object(sodp, &dlmap)) == NULL) {
#ifdef DEBUG
xprintf("%s: %s\n", name, strerror(errno));
#endif
dlerrno = errno;
return NULL;
}
if (LM_PRIVATE(smp)->spd_refcount++ == 0) {
LM_PRIVATE(smp)->spd_flags |= RTLD_DL;
reloc_map(smp);
reloc_copy(smp);
init_map(smp, ".init");
init_map(smp, "_init");
}
return smp;
}
static int
__dlclose(fd)
void *fd;
{
struct so_map *smp = (struct so_map *)fd;
#ifdef DEBUG
xprintf("dlclose(%s): refcount = %d\n", smp->som_path, LM_PRIVATE(smp)->spd_refcount);
#endif
if (--LM_PRIVATE(smp)->spd_refcount != 0)
return 0;
/* Dismantle shared object map and descriptor */
init_map(smp, "_fini");
#if 0
unmap_object(smp);
free(smp->som_sod->sod_name);
free(smp->som_sod);
free(smp);
#endif
return 0;
}
static void *
__dlsym(fd, sym)
void *fd;
char *sym;
{
struct so_map *smp = (struct so_map *)fd, *src_map = NULL;
struct nzlist *np;
long addr;
/*
* Restrict search to passed map if dlopen()ed.
*/
if (LM_PRIVATE(smp)->spd_flags & RTLD_DL)
src_map = smp;
np = lookup(sym, &src_map, 1);
if (np == NULL)
return NULL;
/* Fixup jmpslot so future calls transfer directly to target */
addr = np->nz_value;
if (src_map)
addr += (long)src_map->som_addr;
return (void *)addr;
}
static int
__dlctl(fd, cmd, arg)
void *fd, *arg;
int cmd;
{
switch (cmd) {
case DL_GETERRNO:
*(int *)arg = dlerrno;
return 0;
default:
dlerrno = EOPNOTSUPP;
return -1;
}
return 0;
}
void
#if __STDC__
xprintf(char *fmt, ...)
#else
xprintf(fmt, va_alist)
char *fmt;
#endif
{
char buf[256];
va_list ap;
#if __STDC__
va_start(ap, fmt);
#else
va_start(ap);
#endif
vsprintf(buf, fmt, ap);
(void)write(1, buf, strlen(buf));
va_end(ap);
}