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#include "pdesc.h"
#include "ppkt.h"
#include "psock.h"
#include <arpa/inet.h>
#include <netinet/ip_icmp.h>
void pdesc_init(struct pdesc * desc, uint16_t identifier)
{
desc->state = PDESC_STATE_AUTH;
desc->identifier = identifier;
desc->sequence = 0;
}
static enum pdesc_remote_errno pdesc_check_icmp_type(struct psock * sock, struct pdesc * const desc)
{
if (sock->current.pkt_buf.icmphdr.type == ICMP_ECHO && sock->local.is_client != 0) {
return REMOTE_ICMP_ECHO_CLIENT;
}
if (sock->current.pkt_buf.icmphdr.type == ICMP_ECHOREPLY && sock->local.is_client == 0) {
return REMOTE_ICMP_REPLY_SERVER;
}
return REMOTE_EXISTS;
}
enum pdesc_remote_errno pdesc_find_current_remote(struct psock * sock, struct pdesc ** const desc)
{
size_t i;
*desc = NULL;
if (ppkt_process_icmp(sock) != 0 || ppkt_process_ppkt(sock) != 0) {
return REMOTE_PACKET_INVALID;
}
for (i = 0; i < sock->remotes.used; ++i) {
if (sock->remotes.descriptors[i].state != PDESC_STATE_INVALID &&
sock->current.pkt_buf.icmphdr.un.echo.id == sock->remotes.descriptors[i].identifier) {
*desc = &sock->remotes.descriptors[i];
return pdesc_check_icmp_type(sock, *desc);
}
}
if (i == sock->remotes.max) {
return REMOTE_MAX_DESCRIPTORS;
}
pdesc_init(&sock->remotes.descriptors[i], sock->current.pkt_buf.icmphdr.un.echo.id);
if (pdesc_set_addr(&sock->remotes.descriptors[i].peer, &sock->current.peer_sockaddr) != 0) {
return REMOTE_ADDR_INVALID;
}
*desc = &sock->remotes.descriptors[i];
sock->remotes.used++;
return REMOTE_NOT_FOUND;
}
int pdesc_set_addr(struct paddr * addr, struct sockaddr_storage const * sockaddr)
{
addr->sockaddr = *sockaddr;
switch (sockaddr->ss_family) {
case AF_INET:
struct in_addr in_addr = ((struct sockaddr_in *)sockaddr)->sin_addr;
if (inet_ntop(AF_INET, &in_addr, addr->str, sizeof(struct sockaddr_in)) == NULL) {
return -1;
}
break;
case AF_INET6:
struct in6_addr in6_addr = ((struct sockaddr_in6 *)sockaddr)->sin6_addr;
if (inet_ntop(AF_INET, &in6_addr, addr->str, sizeof(struct sockaddr_in6)) == NULL) {
return -1;
}
break;
default:
return -1;
}
return 0;
}
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