+#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <ctype.h>
#include <dlfcn.h>
+#include "pthread_impl.h"
+#include "libc.h"
+#undef libc
static int errflag;
static char errbuf[128];
#ifdef SHARED
-#include "reloc.h"
-
#if ULONG_MAX == 0xffffffff
typedef Elf32_Ehdr Ehdr;
typedef Elf32_Phdr Phdr;
int refcnt;
Sym *syms;
uint32_t *hashtab;
+ uint32_t *ghashtab;
char *strings;
unsigned char *map;
size_t map_len;
char relocated;
char constructed;
struct dso **deps;
+ void *tls_image;
+ size_t tls_len, tls_size, tls_align, tls_id;
char *shortname;
char buf[];
};
+#include "reloc.h"
+
void __init_ssp(size_t *);
+void *__install_initial_tls(void *);
static struct dso *head, *tail, *libc;
static char *env_path, *sys_path, *r_path;
-static int rtld_used;
static int ssp_used;
static int runtime;
static int ldd_mode;
+static int ldso_fail;
static jmp_buf rtld_fail;
static pthread_rwlock_t lock;
static struct debug debug;
+static size_t *auxv;
+static size_t tls_cnt, tls_size;
struct debug *_dl_debug_addr = &debug;
}
}
-static uint32_t hash(const char *s0)
+static int search_vec(size_t *v, size_t *r, size_t key)
+{
+ for (; v[0]!=key; v+=2)
+ if (!v[0]) return 0;
+ *r = v[1];
+ return 1;
+}
+
+static uint32_t sysv_hash(const char *s0)
{
const unsigned char *s = (void *)s0;
uint_fast32_t h = 0;
return h & 0xfffffff;
}
-static Sym *lookup(const char *s, uint32_t h, struct dso *dso)
+static uint32_t gnu_hash(const char *s0)
+{
+ const unsigned char *s = (void *)s0;
+ uint_fast32_t h = 5381;
+ for (; *s; s++)
+ h = h*33 + *s;
+ return h;
+}
+
+static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
{
size_t i;
Sym *syms = dso->syms;
return 0;
}
+static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
+{
+ Sym *sym;
+ char *strings;
+ uint32_t *hashtab = dso->ghashtab;
+ uint32_t nbuckets = hashtab[0];
+ uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
+ uint32_t h2;
+ uint32_t *hashval;
+ uint32_t n = buckets[h1 % nbuckets];
+
+ if (!n) return 0;
+
+ strings = dso->strings;
+ sym = dso->syms + n;
+ hashval = buckets + nbuckets + (n - hashtab[1]);
+
+ for (h1 |= 1; ; sym++) {
+ h2 = *hashval++;
+ if ((h1 == (h2|1)) && !strcmp(s, strings + sym->st_name))
+ return sym;
+ if (h2 & 1) break;
+ }
+
+ return 0;
+}
+
#define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON)
#define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK)
static void *find_sym(struct dso *dso, const char *s, int need_def)
{
- uint32_t h = hash(s);
+ uint32_t h = 0, gh = 0;
void *def = 0;
- if (h==0x6b366be && !strcmp(s, "dlopen")) rtld_used = 1;
- if (h==0x6b3afd && !strcmp(s, "dlsym")) rtld_used = 1;
- if (h==0x595a4cc && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
+ if (dso->ghashtab) {
+ gh = gnu_hash(s);
+ if (gh == 0x1f4039c9 && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
+ } else {
+ h = sysv_hash(s);
+ if (h == 0x595a4cc && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
+ }
for (; dso; dso=dso->next) {
Sym *sym;
if (!dso->global) continue;
- sym = lookup(s, h, dso);
+ if (dso->ghashtab) {
+ if (!gh) gh = gnu_hash(s);
+ sym = gnu_lookup(s, gh, dso);
+ } else {
+ if (!h) h = sysv_hash(s);
+ sym = sysv_lookup(s, h, dso);
+ }
if (sym && (!need_def || sym->st_shndx) && sym->st_value
&& (1<<(sym->st_info&0xf) & OK_TYPES)
&& (1<<(sym->st_info>>4) & OK_BINDS)) {
return def;
}
-static void do_relocs(unsigned char *base, size_t *rel, size_t rel_size, size_t stride, Sym *syms, char *strings, struct dso *dso)
+static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
{
+ unsigned char *base = dso->base;
+ Sym *syms = dso->syms;
+ char *strings = dso->strings;
Sym *sym;
const char *name;
size_t sym_val, sym_size;
if (sym_index) {
sym = syms + sym_index;
name = strings + sym->st_name;
- ctx = IS_COPY(type) ? dso->next : dso;
+ ctx = IS_COPY(type) ? head->next : head;
sym_val = (size_t)find_sym(ctx, name, IS_PLT(type));
if (!sym_val && sym->st_info>>4 != STB_WEAK) {
snprintf(errbuf, sizeof errbuf,
dso->name, name);
if (runtime) longjmp(rtld_fail, 1);
dprintf(2, "%s\n", errbuf);
- _exit(127);
+ ldso_fail = 1;
+ continue;
}
sym_size = sym->st_size;
+ } else {
+ sym_val = sym_size = 0;
}
do_single_reloc(reloc_addr, type, sym_val, sym_size, base, rel[2]);
}
}
}
-static void *map_library(int fd, size_t *lenp, unsigned char **basep, size_t *dynp)
+static void *map_library(int fd, struct dso *dso)
{
Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
size_t phsize;
unsigned prot;
unsigned char *map, *base;
size_t dyn;
+ size_t tls_image=0;
size_t i;
ssize_t l = read(fd, buf, sizeof buf);
for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
if (ph->p_type == PT_DYNAMIC)
dyn = ph->p_vaddr;
+ if (ph->p_type == PT_TLS) {
+ tls_image = ph->p_vaddr;
+ dso->tls_align = ph->p_align;
+ dso->tls_len = ph->p_filesz;
+ dso->tls_size = ph->p_memsz;
+ }
if (ph->p_type != PT_LOAD) continue;
if (ph->p_vaddr < addr_min) {
addr_min = ph->p_vaddr;
}
if (!runtime) reclaim_gaps(base, (void *)((char *)buf + eh->e_phoff),
eh->e_phentsize, eh->e_phnum);
- *lenp = map_len;
- *basep = base;
- *dynp = dyn;
+ dso->map = map;
+ dso->map_len = map_len;
+ dso->base = base;
+ dso->dynv = (void *)(base+dyn);
+ if (dso->tls_size) dso->tls_image = (void *)(base+tls_image);
return map;
error:
munmap(map, map_len);
z = strchr(s, ':');
l = z ? z-s : strlen(s);
snprintf(buf, buf_size, "%.*s/%s", l, s, name);
- if ((fd = open(buf, O_RDONLY))>=0) return fd;
+ if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
s += l;
}
}
size_t dyn[DYN_CNT] = {0};
decode_vec(p->dynv, dyn, DYN_CNT);
p->syms = (void *)(p->base + dyn[DT_SYMTAB]);
- p->hashtab = (void *)(p->base + dyn[DT_HASH]);
p->strings = (void *)(p->base + dyn[DT_STRTAB]);
+ if (dyn[0]&(1<<DT_HASH))
+ p->hashtab = (void *)(p->base + dyn[DT_HASH]);
+ if (search_vec(p->dynv, dyn, DT_GNU_HASH))
+ p->ghashtab = (void *)(p->base + *dyn);
}
static struct dso *load_library(const char *name)
const char *pathname;
unsigned char *base, *map;
size_t dyno, map_len;
- struct dso *p;
+ struct dso *p, temp_dso = {0};
int fd;
struct stat st;
}
if (strchr(name, '/')) {
pathname = name;
- fd = open(name, O_RDONLY);
+ fd = open(name, O_RDONLY|O_CLOEXEC);
} else {
/* Search for the name to see if it's already loaded */
for (p=head->next; p; p=p->next) {
if (fd < 0 && env_path) fd = path_open(name, env_path, buf, sizeof buf);
if (fd < 0) {
if (!sys_path) {
- FILE *f = fopen(ETC_LDSO_PATH, "r");
+ FILE *f = fopen(ETC_LDSO_PATH, "rbe");
if (f) {
if (getline(&sys_path, (size_t[1]){0}, f) > 0)
sys_path[strlen(sys_path)-1]=0;
return p;
}
}
- map = map_library(fd, &map_len, &base, &dyno);
+ map = map_library(fd, &temp_dso);
close(fd);
if (!map) return 0;
- p = calloc(1, sizeof *p + strlen(pathname) + 1);
+ p = malloc(sizeof *p + strlen(pathname) + 1);
if (!p) {
munmap(map, map_len);
return 0;
}
-
- p->map = map;
- p->map_len = map_len;
- p->base = base;
- p->dynv = (void *)(base + dyno);
+ memcpy(p, &temp_dso, sizeof temp_dso);
decode_dyn(p);
-
+ if (p->tls_image) {
+ p->tls_id = ++tls_cnt;
+ tls_size += p->tls_size + p->tls_align + 8*sizeof(size_t) - 1
+ & -4*sizeof(size_t);
+ }
p->dev = st.st_dev;
p->ino = st.st_ino;
p->refcnt = 1;
p->strings + p->dynv[i+1], p->name);
if (runtime) longjmp(rtld_fail, 1);
dprintf(2, "%s\n", errbuf);
- _exit(127);
+ ldso_fail = 1;
+ continue;
}
if (runtime) {
tmp = realloc(*deps, sizeof(*tmp)*(ndeps+2));
for (; p; p=p->next) {
if (p->relocated) continue;
decode_vec(p->dynv, dyn, DYN_CNT);
- do_relocs(p->base, (void *)(p->base+dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
- 2+(dyn[DT_PLTREL]==DT_RELA), p->syms, p->strings, head);
- do_relocs(p->base, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ],
- 2, p->syms, p->strings, head);
- do_relocs(p->base, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ],
- 3, p->syms, p->strings, head);
+#ifdef NEED_ARCH_RELOCS
+ do_arch_relocs(p, head);
+#endif
+ do_relocs(p, (void *)(p->base+dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
+ 2+(dyn[DT_PLTREL]==DT_RELA));
+ do_relocs(p, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ], 2);
+ do_relocs(p, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ], 3);
p->relocated = 1;
}
}
struct dso *n;
while (p) {
n = p->next;
- if (p->map) free(p);
+ if (p->map && p!=libc && p!=head) free(p);
p = n;
}
}
return 0;
}
+static void find_map_range(Phdr *ph, size_t cnt, size_t stride, struct dso *p)
+{
+ size_t min_addr = -1, max_addr = 0;
+ for (; cnt--; ph = (void *)((char *)ph + stride)) {
+ if (ph->p_type != PT_LOAD) continue;
+ if (ph->p_vaddr < min_addr)
+ min_addr = ph->p_vaddr;
+ if (ph->p_vaddr+ph->p_memsz > max_addr)
+ max_addr = ph->p_vaddr+ph->p_memsz;
+ }
+ min_addr &= -PAGE_SIZE;
+ max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
+ p->map = p->base + min_addr;
+ p->map_len = max_addr - min_addr;
+}
+
static void do_init_fini(struct dso *p)
{
size_t dyn[DYN_CNT] = {0};
{
}
+void *__copy_tls(unsigned char *mem, size_t cnt)
+{
+ struct dso *p;
+ void **dtv = (void *)mem;
+ dtv[0] = (void *)cnt;
+ mem = (void *)(dtv + cnt + 1);
+ for (p=tail; p; p=p->prev) {
+ if (p->tls_id-1 >= cnt) continue;
+ mem += -p->tls_len & (4*sizeof(size_t)-1);
+ mem += ((uintptr_t)p->tls_image - (uintptr_t)mem)
+ & (p->tls_align-1);
+ dtv[p->tls_id] = mem;
+ memcpy(mem, p->tls_image, p->tls_len);
+ mem += p->tls_size;
+ }
+ ((pthread_t)mem)->dtv = dtv;
+ return mem;
+}
+
+void *__tls_get_addr(size_t *p)
+{
+ pthread_t self = __pthread_self();
+ if ((size_t)self->dtv[0] < p[0]) {
+ // FIXME: obtain new DTV and TLS from the DSO
+ a_crash();
+ }
+ return (char *)self->dtv[p[0]] + p[1];
+}
+
void *__dynlink(int argc, char **argv)
{
- size_t *auxv, aux[AUX_CNT] = {0};
+ size_t aux[AUX_CNT] = {0};
size_t i;
Phdr *phdr;
Ehdr *ehdr;
struct dso *const lib = builtin_dsos+1;
struct dso *const vdso = builtin_dsos+2;
char *env_preload=0;
+ size_t vdso_base;
/* Find aux vector just past environ[] */
for (i=argc+1; argv[i]; i++)
lib->name = lib->shortname = "libc.so";
lib->global = 1;
ehdr = (void *)lib->base;
+ find_map_range((void *)(aux[AT_BASE]+ehdr->e_phoff),
+ ehdr->e_phnum, ehdr->e_phentsize, lib);
lib->dynv = (void *)(lib->base + find_dyn(
(void *)(aux[AT_BASE]+ehdr->e_phoff),
ehdr->e_phnum, ehdr->e_phentsize));
if (aux[AT_PHDR]) {
size_t interp_off = 0;
+ size_t tls_image = 0;
/* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
phdr = (void *)aux[AT_PHDR];
for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
app->base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
else if (phdr->p_type == PT_INTERP)
interp_off = (size_t)phdr->p_vaddr;
+ else if (phdr->p_type == PT_TLS) {
+ tls_image = phdr->p_vaddr;
+ app->tls_len = phdr->p_filesz;
+ app->tls_size = phdr->p_memsz;
+ app->tls_align = phdr->p_align;
+ }
}
+ if (app->tls_size) app->tls_image = (char *)app->base + tls_image;
if (interp_off) lib->name = (char *)app->base + interp_off;
app->name = argv[0];
app->dynv = (void *)(app->base + find_dyn(
(void *)aux[AT_PHDR], aux[AT_PHNUM], aux[AT_PHENT]));
+ find_map_range((void *)aux[AT_PHDR],
+ aux[AT_PHNUM], aux[AT_PHENT], app);
} else {
int fd;
char *ldname = argv[0];
_exit(1);
}
runtime = 1;
- ehdr = (void *)map_library(fd, &app->map_len, &app->base, &dyno);
+ ehdr = (void *)map_library(fd, app);
if (!ehdr) {
dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
_exit(1);
close(fd);
lib->name = ldname;
app->name = argv[0];
- app->dynv = (void *)(app->base + dyno);
aux[AT_ENTRY] = ehdr->e_entry;
}
+ if (app->tls_size) {
+ app->tls_id = ++tls_cnt;
+ tls_size += app->tls_size+app->tls_align + 8*sizeof(size_t)-1
+ & -4*sizeof(size_t);
+ }
app->global = 1;
app->constructed = 1;
decode_dyn(app);
/* Attach to vdso, if provided by the kernel */
- for (i=0; auxv[i]; i+=2) {
- size_t vdso_base = auxv[i+1];
- if (auxv[i] != AT_SYSINFO_EHDR) continue;
+ if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {
ehdr = (void *)vdso_base;
phdr = (void *)(vdso_base + ehdr->e_phoff);
for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
decode_dyn(vdso);
vdso->prev = lib;
lib->next = vdso;
- break;
}
/* Initial dso chain consists only of the app. We temporarily
reloc_all(app->next);
reloc_all(app);
+ if (ldso_fail) _exit(127);
if (ldd_mode) _exit(0);
/* Switch to runtime mode: any further failures in the dynamic
* all memory used by the dynamic linker. */
runtime = 1;
+#ifndef DYNAMIC_IS_RO
for (i=0; app->dynv[i]; i+=2)
if (app->dynv[i]==DT_DEBUG)
app->dynv[i+1] = (size_t)&debug;
+#endif
debug.ver = 1;
debug.bp = _dl_debug_state;
debug.head = head;
debug.state = 0;
_dl_debug_state();
+ tls_size += sizeof(struct pthread) + 4*sizeof(size_t);
+ __libc.tls_size = tls_size;
+ __libc.tls_cnt = tls_cnt;
+ if (tls_cnt) {
+ void *mem = mmap(0, __libc.tls_size, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ if (mem==MAP_FAILED ||
+ !__install_initial_tls(__copy_tls(mem, tls_cnt))) {
+ dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
+ argv[0], tls_size);
+ _exit(127);
+ }
+ }
if (ssp_used) __init_ssp(auxv);
do_init_fini(tail);
- if (!rtld_used) {
- free_all(head);
- free(sys_path);
- reclaim((void *)builtin_dsos, 0, sizeof builtin_dsos);
- }
-
errno = 0;
return (void *)aux[AT_ENTRY];
}
p->global = 1;
}
+ if (ssp_used) __init_ssp(auxv);
+
_dl_debug_state();
do_init_fini(tail);
static void *do_dlsym(struct dso *p, const char *s, void *ra)
{
size_t i;
- uint32_t h;
+ uint32_t h = 0, gh = 0;
Sym *sym;
if (p == RTLD_NEXT) {
for (p=head; p && (unsigned char *)ra-p->map>p->map_len; p=p->next);
if (!res) goto failed;
return res;
}
- h = hash(s);
- sym = lookup(s, h, p);
+ if (p->ghashtab) {
+ gh = gnu_hash(s);
+ sym = gnu_lookup(s, gh, p);
+ } else {
+ h = sysv_hash(s);
+ sym = sysv_lookup(s, h, p);
+ }
if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
return p->base + sym->st_value;
if (p->deps) for (i=0; p->deps[i]; i++) {
- sym = lookup(s, h, p);
+ if (p->deps[i]->ghashtab) {
+ if (!gh) gh = gnu_hash(s);
+ sym = gnu_lookup(s, gh, p->deps[i]);
+ } else {
+ if (!h) h = sysv_hash(s);
+ sym = sysv_lookup(s, h, p->deps[i]);
+ }
if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
return p->deps[i]->base + sym->st_value;
}
return 0;
}
-void *__dlsym(void *p, const char *s, void *ra)
+int __dladdr(void *addr, Dl_info *info)
+{
+ struct dso *p;
+ Sym *sym;
+ uint32_t nsym;
+ char *strings;
+ size_t i;
+ void *best = 0;
+ char *bestname;
+
+ pthread_rwlock_rdlock(&lock);
+ for (p=head; p && (unsigned char *)addr-p->map>p->map_len; p=p->next);
+ pthread_rwlock_unlock(&lock);
+
+ if (!p) return 0;
+
+ sym = p->syms;
+ strings = p->strings;
+ if (p->hashtab) {
+ nsym = p->hashtab[1];
+ } else {
+ uint32_t *buckets;
+ uint32_t *hashval;
+ buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
+ sym += p->ghashtab[1];
+ for (i = 0; i < p->ghashtab[0]; i++) {
+ if (buckets[i] > nsym)
+ nsym = buckets[i];
+ }
+ if (nsym) {
+ nsym -= p->ghashtab[1];
+ hashval = buckets + p->ghashtab[0] + nsym;
+ do nsym++;
+ while (!(*hashval++ & 1));
+ }
+ }
+
+ for (; nsym; nsym--, sym++) {
+ if (sym->st_shndx && sym->st_value
+ && (1<<(sym->st_info&0xf) & OK_TYPES)
+ && (1<<(sym->st_info>>4) & OK_BINDS)) {
+ void *symaddr = p->base + sym->st_value;
+ if (symaddr > addr || symaddr < best)
+ continue;
+ best = symaddr;
+ bestname = strings + sym->st_name;
+ if (addr == symaddr)
+ break;
+ }
+ }
+
+ if (!best) return 0;
+
+ info->dli_fname = p->name;
+ info->dli_fbase = p->base;
+ info->dli_sname = bestname;
+ info->dli_saddr = best;
+
+ return 1;
+}
+
+void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
{
void *res;
pthread_rwlock_rdlock(&lock);
{
return 0;
}
-void *__dlsym(void *p, const char *s, void *ra)
+void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
+{
+ return 0;
+}
+int __dladdr (void *addr, Dl_info *info)
{
return 0;
}
projects / musl / blobdiff