Better ICMP code encapsulation

1 files changed, 18 insertions, 89 deletions

diff --git a/server.c b/server.c
index db269e5..9b16173 100644
--- a/server.c
+++ b/server.c
@@ -1,108 +1,37 @@
 #include <stdio.h>
 #include <stdbool.h>
-#include <stddef.h>
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
-#include <stdint.h>
-#include <arpa/inet.h>
-#include <netinet/ip.h>
-#include <netinet/ip_icmp.h>
-#include "icmp.h"
+#include "icmp_server.h"
 #include "util.h"
 
 
-struct state {
-	int socket;
-};
-
-#if 0
-static int icmp_callback(struct nflog_data *ldata, void *state_) {
-	(void)gh; (void)nfmsg;
-
-	struct state *state = (struct state*)state_;
-
-	uint8_t *ip_start;  // received packet, starting at the IP buffer
-	int ip_len = nflog_get_payload(ldata, (char**)&ip_start);
-
-	struct iphdr *hdr = (struct iphdr*)ip_start;
-	int hdr_len = hdr->ihl * 4;
-	uint32_t saddr = hdr->saddr;
-
-	struct icmp_echo *msg = (struct icmp_echo*)(ip_start + hdr_len);
-	int msg_len = ip_len - hdr_len;
-	printf("Received: type %u   code %u   id %hu   seqnum %hu   payload:\n",
-			(unsigned)msg->type, (unsigned)msg->code, msg->id, msg->seqnum);
-	xxd(msg->payload, msg_len - offsetof(struct icmp_echo, payload));
-
-	uint8_t *saddr_bytes = (uint8_t*)&saddr;
-	char ip_address[16];
-	sprintf(ip_address, "%u.%u.%u.%u", saddr_bytes[0], saddr_bytes[1], saddr_bytes[2], saddr_bytes[3]);
-	if (icmp_send_echo_reply(ip_address, msg->id, msg->seqnum, "dank je wel", 11) < 0) {
-		perror("icmp_send_echo_reply");
-	}
-
-	return 0;
-}
-#endif
-
-
 int main(void) {
-	// struct state state;
-	// state.socket = icmp_open_socket();
-	// if (state.socket < 0) {
-	//     perror("icmp_open_socket");
-	//     return 1;
-	// }
-
-	int sock = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
-
-	struct icmp_echo msg;
+	int sock = icmp_server_open_socket();
+	if (sock < 0) {
+		perror("icmp_server_open_socket");
+		return 1;
+	}
 
-	char buf[MAX_IP_PACKET_SIZE];
 	while (true) {
-		struct iovec iov1;
-		memset(&iov1, 0, sizeof iov1);
-		iov1.iov_base = buf;
-		iov1.iov_len = sizeof buf;
-
-		struct sockaddr_in addr;
-
-		struct msghdr recv_msghdr;
-		memset(&recv_msghdr, 0, sizeof recv_msghdr);
-		recv_msghdr.msg_name = &addr;
-		recv_msghdr.msg_namelen = sizeof addr;
-		recv_msghdr.msg_iov = &iov1;
-		recv_msghdr.msg_iovlen = 1;
-
-		ssize_t nr = recvmsg(sock, &recv_msghdr, 0);
-		if (nr < 0) break;
-
-		// buf now contains received data starting at the IP header
-
-		printf("Full packet received:\n");
-		xxd(buf, nr);
-
-		struct iphdr *hdr = (struct iphdr*)buf;
-		int hdr_len = hdr->ihl * 4;
-		uint32_t saddr = hdr->saddr;
+		struct icmp_server_incoming msg = icmp_server_receive(sock);
+		if (msg.data == NULL) {
+			perror("icmp_server_communicate");
+			return 1;
+		}
 
-		struct icmp_echo *msg = (struct icmp_echo*)(buf + hdr_len);
-		int msg_len = nr - hdr_len;
-		printf("Received: type %u   code %u   id %hu   seqnum %hu   payload:\n",
-				(unsigned)msg->type, (unsigned)msg->code, msg->id, msg->seqnum);
-		xxd(msg->payload, msg_len - offsetof(struct icmp_echo, payload));
+		printf("Received: type %d   id %d   seqnum %d   data:\n", msg.type, msg.id, msg.seqnum);
+		xxd(msg.data, msg.length);
 
-		if (msg->type != ICMP_ECHO) {
+		if (msg.type != ICMP_ECHO) {
 			printf("Not an ICMP_ECHO, ignoring\n");
 			continue;
 		}
 
-		uint8_t *saddr_bytes = (uint8_t*)&saddr;
-		char ip_address[16];
-		sprintf(ip_address, "%u.%u.%u.%u", saddr_bytes[0], saddr_bytes[1], saddr_bytes[2], saddr_bytes[3]);
-		if (icmp_send_echo_reply(ip_address, msg->id, msg->seqnum, "dank je wel", 11) < 0) {
-			perror("icmp_send_echo_reply");
+		if (icmp_server_send_reply(sock, msg.source_addr, msg.id, msg.seqnum, "dank je wel", 11) < 0) {
+			perror("icmp_server_send_reply");
 		}
 	}
+
+	close(sock);
 }