/**
* Add a symbol name in .strtab
* @param file
* @param name
* @return
*/
int elfsh_insert_in_strtab(elfshobj_t *file, char *name)
{
elfshsect_t *sect;
u_int len;
u_int index;
int ret;
PROFILER_IN(__FILE__, __FUNCTION__, __LINE__);
if (file == NULL || name == NULL)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Invalid NULL parameter", -1);
sect = elfsh_get_strtab(file, -1);
if (sect == NULL)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Unable to get STRTAB", -1);
len = strlen(name);
if (!len)
for (index = 0; index < sect->shdr->sh_size; index++)
if (*(char *) sect->data + index == 0x00)
PROFILER_ROUT(__FILE__, __FUNCTION__, __LINE__, (index));
ret = elfsh_append_data_to_section(sect, name, len + 1);
if (ret < 0)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Failed to append data to strtab", -1);
PROFILER_ROUT(__FILE__, __FUNCTION__, __LINE__, ret);
}
/**
* Add a section name in runtime section string table
* @param file
* @param name
* @return
*/
int elfsh_insert_in_rshstrtab(elfshobj_t *file, char *name)
{
int ret;
PROFILER_IN(__FILE__, __FUNCTION__, __LINE__);
if (name == NULL || file == NULL ||
file->secthash[ELFSH_SECTION_RSHSTRTAB] == NULL)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Invalid NULL parameter", -1);
ret = elfsh_append_data_to_section(file->secthash[ELFSH_SECTION_RSHSTRTAB],
name, strlen(name) + 1);
if (ret < 0)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Failed to append data to rshstrtab", -1);
else
PROFILER_ROUT(__FILE__, __FUNCTION__, __LINE__, ret);
}
/**
* Add a symbol name in .dynstr
* @param file
* @param name
* @return
*/
int elfsh_insert_in_dynstr(elfshobj_t *file, char *name)
{
elfshsect_t *sect;
int ret;
PROFILER_IN(__FILE__, __FUNCTION__, __LINE__);
if (file == NULL || name == NULL)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Invalid NULL parameter", -1);
sect = elfsh_get_section_by_name(file, ELFSH_SECTION_NAME_DYNSTR, NULL, NULL, NULL);
if (sect == NULL)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Unable to find DYNSTR by name", -1);
ret = elfsh_append_data_to_section(sect, name, strlen(name) + 1);
if (ret < 0)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Failed to append data to dynstr", -1);
else
PROFILER_ROUT(__FILE__, __FUNCTION__, __LINE__, ret);
}
/**
* Insert a symbol in the given symbol table
* This function is not e2dbg safe
* @param sect
* @param sym
* @param name
* @return
*/
int elfsh_insert_symbol(elfshsect_t *sect,
elfsh_Sym *sym,
char *name)
{
elfsh_Sym *orig;
int index;
int mode;
hash_t *uptable;
PROFILER_IN(__FILE__, __FUNCTION__, __LINE__);
//fprintf(stderr, "Adding symbol %s \n", name);
/* Sanity checks */
if (sect == NULL || sect->shdr == NULL ||
(sect->shdr->sh_type != SHT_SYMTAB &&
sect->shdr->sh_type != SHT_DYNSYM))
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Input section is not SYMTAB", -1);
if (name == NULL)
name = ELFSH_NULL_STRING;
/* Check if symbol already exists */
orig = elfsh_get_symbol_by_name(sect->parent, name);
if (orig != NULL && sym->st_value == orig->st_value)
PROFILER_ROUT(__FILE__, __FUNCTION__, __LINE__,
(((char *) orig - (char *) sect->data) /
ELFSH_SYMTAB_ENTRY_SIZE));
/* Shift some special symbols */
//if (sect->shdr->sh_type == SHT_DYNSYM)
//fprintf(stderr, "Shifting usual symbols\n");
mode = elfsh_get_mode();
elfsh_set_static_mode();
elfsh_shift_usualsyms(sect, sym);
elfsh_set_mode(mode);
//fprintf(stderr, "Shifted usual symbols\n");
/* Insert symbol name in .shstrtab */
index = elfsh_insert_in_strtab(sect->parent, name);
if (index < 0)
PROFILER_ERR(__FILE__, __FUNCTION__, __LINE__,
"Unable to insert in SHSTRTAB", -1);
#if __DEBUG_RELADD__
fprintf(stderr, "[DEBUG_RELADD] Injected symbol %-20s [" AFMT "] \n",
name, (eresi_Addr) sym->st_value);
#endif
/* Insert symbol in .symtab */
sym->st_name = index;
index = elfsh_append_data_to_section(sect, sym, sizeof(elfsh_Sym));
/* Update hashtable */
switch(sect->shdr->sh_type)
{
case SHT_SYMTAB:
uptable = §->parent->symhash;
break;
case SHT_DYNSYM:
uptable = §->parent->dynsymhash;
break;
default:
uptable = NULL;
break;
}
if (uptable && uptable->ent)
hash_add(uptable, strdup(name), (void *) index);
PROFILER_ROUT(__FILE__, __FUNCTION__, __LINE__, sym->st_name);
}
