Skip to content

Commit

Permalink
src: memory management using smart pointer
Browse files Browse the repository at this point in the history 
Introduced use of smart pointers instead of MallocedBuffer to manage
memory allocated in the cares library.

PR-URL: #23628
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Joyee Cheung <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Refael Ackermann <[email protected]>
  • Loading branch information
@uttampawar @MylesBorins
uttampawar authored and MylesBorins committed Dec 26, 2018
1 parent c6a43fa commit 383d512
Showing 1 changed file with 54 additions and 55 deletions.
109 changes: 54 additions & 55 deletions src/cares_wrap.cc
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1061,118 +1061,117 @@ int ParseSoaReply(Environment* env,
EscapableHandleScope handle_scope(env->isolate());
auto context = env->context();

/* Can't use ares_parse_soa_reply() here which can only parse single record */
unsigned int ancount = cares_get_16bit(buf + 6);
// Manage memory using standardard smart pointer std::unique_tr
struct AresDeleter {
void operator()(char* ptr) const noexcept { ares_free_string(ptr); }
};
using ares_unique_ptr = std::unique_ptr<char[], AresDeleter>;

// Can't use ares_parse_soa_reply() here which can only parse single record
const unsigned int ancount = cares_get_16bit(buf + 6);
unsigned char* ptr = buf + NS_HFIXEDSZ;
char* name;
char* rr_name;
char* name_temp;
long temp_len; // NOLINT(runtime/int)
int status = ares_expand_name(ptr, buf, len, &name, &temp_len);
int status = ares_expand_name(ptr, buf, len, &name_temp, &temp_len);
const ares_unique_ptr name(name_temp);
if (status != ARES_SUCCESS) {
/* returns EBADRESP in case of invalid input */
// returns EBADRESP in case of invalid input
return status == ARES_EBADNAME ? ARES_EBADRESP : status;
}

if (ptr + temp_len + NS_QFIXEDSZ > buf + len) {
free(name);
return ARES_EBADRESP;
}
ptr += temp_len + NS_QFIXEDSZ;

for (unsigned int i = 0; i < ancount; i++) {
status = ares_expand_name(ptr, buf, len, &rr_name, &temp_len);
char* rr_name_temp;
long rr_temp_len; // NOLINT(runtime/int)
int status2 = ares_expand_name(ptr, buf, len, &rr_name_temp, &rr_temp_len);
const ares_unique_ptr rr_name(rr_name_temp);

if (status != ARES_SUCCESS)
break;
if (status2 != ARES_SUCCESS)
return status2 == ARES_EBADNAME ? ARES_EBADRESP : status2;

ptr += temp_len;
ptr += rr_temp_len;
if (ptr + NS_RRFIXEDSZ > buf + len) {
free(rr_name);
status = ARES_EBADRESP;
break;
return ARES_EBADRESP;
}

const int rr_type = cares_get_16bit(ptr);
const int rr_len = cares_get_16bit(ptr + 8);
ptr += NS_RRFIXEDSZ;

/* only need SOA */
// only need SOA
if (rr_type == ns_t_soa) {
ares_soa_reply soa;

status = ares_expand_name(ptr, buf, len, &soa.nsname, &temp_len);
if (status != ARES_SUCCESS) {
free(rr_name);
break;
char* nsname_temp;
long nsname_temp_len; // NOLINT(runtime/int)

int status3 = ares_expand_name(ptr, buf, len,
&nsname_temp,
&nsname_temp_len);
const ares_unique_ptr nsname(nsname_temp);
if (status3 != ARES_SUCCESS) {
return status3 == ARES_EBADNAME ? ARES_EBADRESP : status3;
}
ptr += temp_len;

status = ares_expand_name(ptr, buf, len, &soa.hostmaster, &temp_len);
if (status != ARES_SUCCESS) {
free(rr_name);
free(soa.nsname);
break;
ptr += nsname_temp_len;

char* hostmaster_temp;
long hostmaster_temp_len; // NOLINT(runtime/int)
int status4 = ares_expand_name(ptr, buf, len,
&hostmaster_temp,
&hostmaster_temp_len);
const ares_unique_ptr hostmaster(hostmaster_temp);
if (status4 != ARES_SUCCESS) {
return status4 == ARES_EBADNAME ? ARES_EBADRESP : status4;
}
ptr += temp_len;
ptr += hostmaster_temp_len;

if (ptr + 5 * 4 > buf + len) {
free(rr_name);
free(soa.nsname);
free(soa.hostmaster);
status = ARES_EBADRESP;
break;
return ARES_EBADRESP;
}

soa.serial = cares_get_32bit(ptr + 0 * 4);
soa.refresh = cares_get_32bit(ptr + 1 * 4);
soa.retry = cares_get_32bit(ptr + 2 * 4);
soa.expire = cares_get_32bit(ptr + 3 * 4);
soa.minttl = cares_get_32bit(ptr + 4 * 4);
const unsigned int serial = cares_get_32bit(ptr + 0 * 4);
const unsigned int refresh = cares_get_32bit(ptr + 1 * 4);
const unsigned int retry = cares_get_32bit(ptr + 2 * 4);
const unsigned int expire = cares_get_32bit(ptr + 3 * 4);
const unsigned int minttl = cares_get_32bit(ptr + 4 * 4);

Local<Object> soa_record = Object::New(env->isolate());
soa_record->Set(context,
env->nsname_string(),
OneByteString(env->isolate(), soa.nsname)).FromJust();
OneByteString(env->isolate(), nsname.get())).FromJust();
soa_record->Set(context,
env->hostmaster_string(),
OneByteString(env->isolate(),
soa.hostmaster)).FromJust();
hostmaster.get())).FromJust();
soa_record->Set(context,
env->serial_string(),
Integer::New(env->isolate(), soa.serial)).FromJust();
Integer::New(env->isolate(), serial)).FromJust();
soa_record->Set(context,
env->refresh_string(),
Integer::New(env->isolate(), soa.refresh)).FromJust();
Integer::New(env->isolate(), refresh)).FromJust();
soa_record->Set(context,
env->retry_string(),
Integer::New(env->isolate(), soa.retry)).FromJust();
Integer::New(env->isolate(), retry)).FromJust();
soa_record->Set(context,
env->expire_string(),
Integer::New(env->isolate(), soa.expire)).FromJust();
Integer::New(env->isolate(), expire)).FromJust();
soa_record->Set(context,
env->minttl_string(),
Integer::New(env->isolate(), soa.minttl)).FromJust();
Integer::New(env->isolate(), minttl)).FromJust();
soa_record->Set(context,
env->type_string(),
env->dns_soa_string()).FromJust();

free(soa.nsname);
free(soa.hostmaster);

*ret = handle_scope.Escape(soa_record);
break;
}

free(rr_name);
ptr += rr_len;
}

free(name);

if (status != ARES_SUCCESS) {
return status == ARES_EBADNAME ? ARES_EBADRESP : status;
}

return ARES_SUCCESS;
}

Expand Down

0 comments on commit 383d512

Please sign in to comment.