0,0 → 1,218 |
/* |
* Copyright (c) 2008 Jiri Svoboda |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - 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. |
* - 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. |
*/ |
|
/** @addtogroup rtld rtld |
* @brief |
* @{ |
*/ |
/** |
* @file |
*/ |
|
#include <stdio.h> |
#include <stdlib.h> |
#include <unistd.h> |
#include <fcntl.h> |
#include <libadt/list.h> |
|
#include <rtld.h> |
#include <dynamic.h> |
#include <pcb.h> |
#include <elf_load.h> |
#include <arch.h> |
#include <module.h> |
|
/** (Eagerly) process all relocation tables in a module. |
* |
* Currently works as if LD_BIND_NOW was specified. |
*/ |
void module_process_relocs(module_t *m) |
{ |
printf("module_process_relocs('%s')\n", m->dyn.soname); |
if (m->dyn.plt_rel == DT_REL) { |
if (m->dyn.rel != NULL) |
rel_table_process(m, m->dyn.rel, m->dyn.rel_sz); |
/* FIXME: this seems wrong */ |
if (m->dyn.jmp_rel != NULL) |
rel_table_process(m, m->dyn.jmp_rel, m->dyn.plt_rel_sz); |
} else { /* (m->dyn.plt_rel == DT_RELA) */ |
printf("table type DT_RELA\n"); |
if (m->dyn.rela != NULL) { |
printf("non-empty\n"); |
rela_table_process(m, m->dyn.rela, m->dyn.rela_sz); |
} |
} |
} |
|
/** Find module structure by soname. |
* |
* Used primarily to see if a module has already been loaded. |
*/ |
module_t *module_find(char *soname) |
{ |
link_t *head = &runtime_env.modules_head; |
|
link_t *cur; |
module_t *m; |
|
/* FIXME!! */ |
if (soname[0] == '.') return &runtime_env.rtld; |
|
for (cur = head->next; cur != head; cur = cur->next) { |
m = list_get_instance(cur, module_t, modules_link); |
if (strcmp(m->dyn.soname, soname) == 0) { |
return m; /* Found */ |
} |
} |
|
return NULL; /* Not found */ |
} |
|
#define NAME_BUF_SIZE 64 |
|
/** Load a module. |
* |
* Currently this trivially tries to load '/<soname>'. |
*/ |
module_t *module_load(char *soname) |
{ |
elf_info_t info; |
char name_buf[NAME_BUF_SIZE]; |
module_t *m; |
int rc; |
|
m = malloc(sizeof(module_t)); |
if (!m) { |
printf("malloc failed\n"); |
exit(1); |
} |
|
printf("Requested load of module '%s'\n", soname); |
|
if (strlen(soname) > NAME_BUF_SIZE - 2) { |
printf("soname too long. increase NAME_BUF_SIZE\n"); |
exit(1); |
} |
|
/* Prepend soname with slash */ |
name_buf[0] = '/'; |
strcpy(name_buf + 1, soname); |
|
/* FIXME: need to vary bias / allocate address space */ |
m->bias = 0x20000; |
printf("filename:'%s'\n", name_buf); |
|
rc = elf_load_file(name_buf, m->bias, &info); |
if (rc < 0) { |
printf("Failed to load '%s'\n"); |
exit(1); |
} |
|
printf("parse dynamic section\n"); |
/* Parse ELF .dynamic section. Store info to m->dyn. */ |
dynamic_parse(info.dynamic, m->bias, &m->dyn); |
printf("...\n"); |
|
/* Insert into the list of loaded modules */ |
list_append(&m->modules_link, &runtime_env.modules_head); |
|
return m; |
} |
|
/** Load all modules on which m (transitively) depends. |
*/ |
void module_load_deps(module_t *m) |
{ |
elf_dyn_t *dp; |
char *dep_soname; |
module_t *dm; |
size_t n, i; |
|
/* Count direct dependencies */ |
|
dp = m->dyn.dynamic; |
n = 0; |
|
while (dp->d_tag != DT_NULL) { |
if (dp->d_tag == DT_NEEDED) ++n; |
++dp; |
} |
|
/* Create an array of pointers to direct dependencies */ |
|
m->n_deps = n; |
if (n > 0) |
m->deps = malloc(n * sizeof(module_t *)); |
else |
m->deps = NULL; |
|
if (!m->deps) { |
printf("malloc failed\n"); |
exit(1); |
} |
|
i = 0; /* Current dependency index */ |
dp = m->dyn.dynamic; |
|
while (dp->d_tag != DT_NULL) { |
if (dp->d_tag == DT_NEEDED) { |
dep_soname = m->dyn.str_tab + dp->d_un.d_val; |
printf("needed:'%s'\n", dep_soname); |
|
dm = module_find(dep_soname); |
if (!dm) { |
dm = module_load(dep_soname); |
module_load_deps(dm); |
} |
|
/* Save into deps table */ |
m->deps[i++] = dm; |
} |
++dp; |
} |
} |
|
void modules_process_relocs(void) |
{ |
link_t *head = &runtime_env.modules_head; |
|
link_t *cur; |
module_t *m; |
|
for (cur = head->next; cur != head; cur = cur->next) { |
m = list_get_instance(cur, module_t, modules_link); |
|
/* Skip rtld, since it has already been processed */ |
if (m != &runtime_env.rtld) { |
module_process_relocs(m); |
} |
} |
} |
|
/** @} |
*/ |