// binary search function for get_aon_index_binary()
static int
find_aon_idx_bin(
vmi_instance_t vmi,
const char *symbol,
addr_t aon_base_va,
int low,
int high,
addr_t base_addr,
vmi_pid_t pid)
{
int mid, cmp;
addr_t str_rva_loc; // location of curr name's RVA
uint32_t str_rva; // RVA of curr name
char *name = 0; // curr name
if (high < low)
goto not_found;
// calc the current index ("mid")
mid = (low + high) / 2;
str_rva_loc = aon_base_va + mid * sizeof(uint32_t);
vmi_read_32_va(vmi, str_rva_loc, pid, &str_rva);
if (!str_rva)
goto not_found;
// get the curr string & compare to symbol
name = rva_to_string(vmi, (addr_t) str_rva, base_addr, pid);
if(!name)
goto not_found;
cmp = strcmp(symbol, name);
free(name);
if (cmp < 0) { // symbol < name ==> try lower region
return find_aon_idx_bin(vmi, symbol, aon_base_va, low, mid - 1, base_addr, pid);
}
else if (cmp > 0) { // symbol > name ==> try higher region
return find_aon_idx_bin(vmi, symbol, aon_base_va, mid + 1, high, base_addr, pid);
}
else { // symbol == name
return mid; // found
}
not_found:
return -1;
}
// binary search function for get_aon_index_binary()
static int
find_aon_idx_bin(
vmi_instance_t vmi,
const char *symbol,
addr_t aon_base_va,
int low,
int high,
const access_context_t *ctx)
{
access_context_t _ctx = *ctx;
int mid, cmp;
uint32_t str_rva = 0; // RVA of curr name
char *name = 0; // curr name
if (high < low)
goto not_found;
// calc the current index ("mid")
mid = (low + high) / 2;
_ctx.addr = aon_base_va + mid * sizeof(uint32_t);
if (VMI_FAILURE == vmi_read_32(vmi, &_ctx, &str_rva) || !str_rva)
goto not_found;
// get the curr string & compare to symbol
_ctx.addr = ctx->addr + str_rva;
name = vmi_read_str(vmi, &_ctx);
if (!name)
goto not_found;
cmp = strcmp(symbol, name);
free(name);
if (cmp < 0) { // symbol < name ==> try lower region
return find_aon_idx_bin(vmi, symbol, aon_base_va, low, mid - 1, ctx);
} else if (cmp > 0) { // symbol > name ==> try higher region
return find_aon_idx_bin(vmi, symbol, aon_base_va, mid + 1, high, ctx);
} else { // symbol == name
return mid; // found
}
not_found:
return -1;
}
// Finds the index of the exported symbol specified - binary search
int
get_aon_index_binary(
vmi_instance_t vmi,
const char *symbol,
struct export_table *et,
const access_context_t *ctx)
{
addr_t aon_base_addr = ctx->addr + et->address_of_names;
int name_ct = et->number_of_names;
return find_aon_idx_bin(vmi, symbol, aon_base_addr, 0, name_ct - 1, ctx);
}
// Finds the index of the exported symbol specified - binary search
int
get_aon_index_binary(
vmi_instance_t vmi,
const char *symbol,
struct export_table *et,
addr_t base_addr,
vmi_pid_t pid)
{
addr_t aon_base_addr = base_addr + et->address_of_names;
int name_ct = et->number_of_names;
return find_aon_idx_bin(vmi, symbol, aon_base_addr, 0, name_ct - 1, base_addr, pid);
}
