[dhcp_relay] fix data type in dhcp6relay, add protection in packet data parsing (#9036)

This commit is contained in:
kellyyeh 2021-10-21 23:00:37 -07:00 committed by Ying Xie
parent bb1bc59a22
commit 517d81a57a

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@ -515,14 +515,16 @@ void relay_client(int sock, const uint8_t *msg, int32_t len, const ip6_hdr *ip_h
void callback(evutil_socket_t fd, short event, void *arg) {
struct relay_config *config = (struct relay_config *)arg;
static uint8_t message_buffer[4096];
uint32_t len = recv(config->filter, message_buffer, 4096, 0);
int32_t len = recv(config->filter, message_buffer, 4096, 0);
if (len <= 0) {
syslog(LOG_WARNING, "recv: Failed to receive data at filter socket\n");
syslog(LOG_WARNING, "recv: Failed to receive data at filter socket: %s\n", strerror(errno));
return;
}
char* ptr = (char *)message_buffer;
const uint8_t *current_position = (uint8_t *)ptr;
const uint8_t *current_position = (uint8_t *)ptr;
const uint8_t *tmp = NULL;
const uint8_t *prev = NULL;
auto ether_header = parse_ether_frame(current_position, &tmp);
current_position = tmp;
@ -530,14 +532,19 @@ void callback(evutil_socket_t fd, short event, void *arg) {
auto ip_header = parse_ip6_hdr(current_position, &tmp);
current_position = tmp;
prev = current_position;
if (ip_header->ip6_ctlun.ip6_un1.ip6_un1_nxt != IPPROTO_UDP) {
const struct ip6_ext *ext_header;
do {
ext_header = (const struct ip6_ext *)current_position;
current_position += ext_header->ip6e_len;
if((current_position == prev) || (current_position >= (uint8_t *)ptr + sizeof(message_buffer))) {
return;
}
prev = current_position;
}
while (ext_header->ip6e_nxt != IPPROTO_UDP);
}
}
auto udp_header = parse_udp(current_position, &tmp);
current_position = tmp;