aboutsummaryrefslogtreecommitdiff
path: root/Semestr 4/sieci/pracownia2
diff options
context:
space:
mode:
Diffstat (limited to 'Semestr 4/sieci/pracownia2')
-rw-r--r--Semestr 4/sieci/pracownia2/router.c212
-rwxr-xr-xSemestr 4/sieci/pracownia2/udp_client.c33
-rwxr-xr-xSemestr 4/sieci/pracownia2/udp_server.c59
3 files changed, 304 insertions, 0 deletions
diff --git a/Semestr 4/sieci/pracownia2/router.c b/Semestr 4/sieci/pracownia2/router.c
new file mode 100644
index 0000000..79754b3
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/router.c
@@ -0,0 +1,212 @@
+#include <stdio.h>
+#include <errno.h>
+#include <strings.h>
+#include <string.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <poll.h>
+#include <time.h>
+#include <unistd.h>
+
+#define SERVER_PORT 54321
+#define TURN_LEN_S 5
+#define TURN_LEN_MS (1000 * TURN_LEN_S)
+#define TURN_LEN_US (1000000 * TURN_LEN_S)
+#define NS_TO_MS(X) ((long)(X) / (long)1000000)
+#define S_TO_MS(X) ((long)(X) * (long)1000)
+
+struct router_addr {
+ struct in_addr addr;
+ uint16_t distance;
+ uint8_t netmask;
+};
+
+struct in_addr get_broadcast_address(struct router_addr ra) {
+ struct in_addr result = ra.addr;
+ /* bitshift by more than 31 is UB */
+ if (ra.netmask < 32) {
+ result.s_addr |= ~((1<<ra.netmask) - 1);
+ }
+ return result;
+}
+
+void pretty_print(struct router_addr ra) {
+ char ip_addr[20];
+ inet_ntop(AF_INET, &ra.addr, ip_addr, sizeof(ip_addr));
+ printf("%s/%d distance %d\n", ip_addr, ra.netmask, ra.distance);
+}
+
+/* converts string of IP with netmask in CIDR notation to router_addr */
+struct router_addr stora(char *str) {
+ struct router_addr result;
+ char addr[20];
+ size_t ip_preffix = strcspn(str, "/");
+
+ strncpy(addr, str, strlen(str));
+ addr[ip_preffix] = 0;
+ inet_pton(AF_INET, addr, &(result.addr));
+ result.netmask = atoi(str + ip_preffix + 1);
+ return result;
+}
+
+int get_socket() {
+ int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sockfd < 0) {
+ fprintf(stderr, "Socket error: %s\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ return sockfd;
+}
+
+void bind_to_port(int sockfd, uint16_t port) {
+ struct sockaddr_in server_address;
+ bzero(&server_address, sizeof(server_address));
+ server_address.sin_family = AF_INET;
+ server_address.sin_port = htons(port);
+ server_address.sin_addr.s_addr = htonl(INADDR_ANY);
+ if (bind(sockfd, (struct sockaddr*)&server_address, sizeof(server_address)) < 0) {
+ fprintf(stderr, "Bind error: %s\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+
+ int broadcastPermission = 1;
+ setsockopt (sockfd, SOL_SOCKET, SO_BROADCAST, (void *)&broadcastPermission, sizeof(broadcastPermission));
+}
+
+uint16_t read_configuration(struct router_addr** networks) {
+ uint16_t n;
+ scanf("%hd", &n);
+ *networks = malloc(n * sizeof(struct router_addr));
+ for (int i = 0; i < n; i++) {
+ char addr[20];
+ char _dist[10];
+ uint16_t dist;
+ scanf(" %s %s %hd", addr, _dist, &dist);
+ (*networks)[i] = stora(addr);
+ (*networks)[i].distance = dist;
+ }
+ return n;
+}
+
+long get_time_interval(struct timespec start, struct timespec finish) {
+ return S_TO_MS(finish.tv_sec - start.tv_sec) + NS_TO_MS(finish.tv_nsec - start.tv_nsec);
+}
+
+int poll_modify_timeout(struct pollfd *fds, nfds_t nfd, int *timeout) {
+ if (*timeout < 0) {
+ fprintf(stderr, "poll_modify_timeout: timeout is negative.\n");
+ exit(EXIT_FAILURE);
+ }
+
+ struct timespec start;
+ clock_gettime(CLOCK_REALTIME, &start);
+ int result = poll(fds, nfd, *timeout);
+
+ if (result == -1) {
+ fprintf(stderr, "poll error: %s\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ if (result == 0) {
+ *timeout = 0;
+ return 0;
+ }
+ struct timespec finish;
+ clock_gettime(CLOCK_REALTIME, &finish);
+ *timeout -= get_time_interval(start, finish);
+ printf("Timeout: %dms, time waiting: %ldms.\n", *timeout, get_time_interval(start, finish));
+ return result;
+}
+
+/* For debug purposes only */
+void recv_and_print(int sockfd, int networks_number, struct router_addr *networks) {
+ struct sockaddr_in sender;
+ socklen_t sender_len = sizeof(sender);
+ uint8_t buffer[IP_MAXPACKET + 1];
+ ssize_t datagram_len = recvfrom(sockfd, buffer, IP_MAXPACKET, 0,
+ (struct sockaddr*)&sender, &sender_len);
+ if (datagram_len < 0) {
+ fprintf(stderr, "recvfrom error: %s\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ for (int i = 0; i < networks_number; i++) {
+ if (networks[i].addr.s_addr == sender.sin_addr.s_addr) {
+ return;
+ }
+ }
+
+ char sender_ip_str[20];
+ inet_ntop(AF_INET, &(sender.sin_addr), sender_ip_str, sizeof(sender_ip_str));
+ printf("Received UDP packet from IP address: %s, port %d\n",
+ sender_ip_str, ntohs(sender.sin_port));
+
+ buffer[datagram_len] = 0;
+ printf("%ld-byte message: +%s+\n", datagram_len, buffer);
+
+}
+
+void listen_for_routers(int sockfd, int timeout, int networks_number, struct router_addr *netowrks) {
+ printf("Listening for %dms.\n", timeout);
+ struct pollfd fds;
+ fds.fd = sockfd;
+ fds.events = POLLIN;
+ fds.revents = 0;
+ while (poll_modify_timeout(&fds, 1, &timeout)) {
+ printf("Poll returned, remaining timeout: %dms.\n", timeout);
+ recv_and_print(sockfd, networks_number, netowrks);
+ }
+ printf("Finished listening\n");
+}
+
+int send_distance_vector(int sockfd, struct in_addr network) {
+ struct sockaddr_in network_address;
+ bzero (&network_address, sizeof(network_address));
+ network_address.sin_family = AF_INET;
+ network_address.sin_port = htons(SERVER_PORT);
+ network_address.sin_addr = network;
+
+ char* message = "Hello server! My name is S1\n";
+ ssize_t message_len = strlen(message);
+ int result;
+
+ char addr[20];
+ inet_ntop(AF_INET, &network, addr, sizeof(addr));
+ printf("Sending datagram to %s\n", addr);
+ if ((result = sendto(sockfd, message, message_len, 0, (struct sockaddr*) &network_address, sizeof(network_address))) != message_len) {
+ fprintf(stderr, "sendto error: %s\n", strerror(errno));
+ // return EXIT_FAILURE;
+ }
+}
+
+void propagate_distance_vector(int sockfd, int networks_number, struct router_addr *networks) {
+ printf("Propagating distance vector\n");
+ for (int i = 0; i < networks_number; i++) {
+ struct in_addr broadcast_address = get_broadcast_address(networks[i]);
+ send_distance_vector(sockfd, broadcast_address);
+ }
+ printf("Distance vector propagated.\n");
+}
+
+void router_loop(int sockfd, int networks_number, struct router_addr *networks) {
+ printf("Starting the router loop...\n");
+ for (;;) {
+ listen_for_routers(sockfd, TURN_LEN_MS, networks_number, networks);
+ propagate_distance_vector(sockfd, networks_number, networks);
+ }
+}
+
+int main() {
+ struct router_addr* networks;
+ int n = read_configuration(&networks);
+ for (int i = 0; i < n; i++) {
+ pretty_print(networks[i]);
+ }
+
+ int sockfd = get_socket();
+ bind_to_port(sockfd, SERVER_PORT);
+ router_loop(sockfd, n, networks);
+
+ close(sockfd);
+ free(networks);
+} \ No newline at end of file
diff --git a/Semestr 4/sieci/pracownia2/udp_client.c b/Semestr 4/sieci/pracownia2/udp_client.c
new file mode 100755
index 0000000..5624484
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/udp_client.c
@@ -0,0 +1,33 @@
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+int main()
+{
+ int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sockfd < 0) {
+ fprintf(stderr, "socket error: %s\n", strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ struct sockaddr_in server_address;
+ bzero (&server_address, sizeof(server_address));
+ server_address.sin_family = AF_INET;
+ server_address.sin_port = htons(54321);
+ inet_pton(AF_INET, "192.168.1.2", &server_address.sin_addr);
+
+ char* message = "Hello server!";
+ ssize_t message_len = strlen(message);
+ if (sendto(sockfd, message, message_len, 0, (struct sockaddr*) &server_address, sizeof(server_address)) != message_len) {
+ fprintf(stderr, "sendto error: %s\n", strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ close (sockfd);
+ return EXIT_SUCCESS;
+}
+
diff --git a/Semestr 4/sieci/pracownia2/udp_server.c b/Semestr 4/sieci/pracownia2/udp_server.c
new file mode 100755
index 0000000..b5ae6d1
--- /dev/null
+++ b/Semestr 4/sieci/pracownia2/udp_server.c
@@ -0,0 +1,59 @@
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+int main()
+{
+ int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sockfd < 0) {
+ fprintf(stderr, "socket error: %s\n", strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ struct sockaddr_in server_address;
+ bzero (&server_address, sizeof(server_address));
+ server_address.sin_family = AF_INET;
+ server_address.sin_port = htons(54321);
+ server_address.sin_addr.s_addr = htonl(INADDR_ANY);
+ if (bind (sockfd, (struct sockaddr*)&server_address, sizeof(server_address)) < 0) {
+ fprintf(stderr, "bind error: %s\n", strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ for (;;) {
+
+ struct sockaddr_in sender;
+ socklen_t sender_len = sizeof(sender);
+ u_int8_t buffer[IP_MAXPACKET+1];
+
+ ssize_t datagram_len = recvfrom (sockfd, buffer, IP_MAXPACKET, 0, (struct sockaddr*)&sender, &sender_len);
+ if (datagram_len < 0) {
+ fprintf(stderr, "recvfrom error: %s\n", strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ char sender_ip_str[20];
+ inet_ntop(AF_INET, &(sender.sin_addr), sender_ip_str, sizeof(sender_ip_str));
+ printf ("Received UDP packet from IP address: %s, port: %d\n", sender_ip_str, ntohs(sender.sin_port));
+
+ buffer[datagram_len] = 0;
+ printf ("%ld-byte message: +%s+\n", datagram_len, buffer);
+
+ char* reply = "Thank you!";
+ ssize_t reply_len = strlen(reply);
+ if (sendto(sockfd, reply, reply_len, 0, (struct sockaddr*)&sender, sender_len) != reply_len) {
+ fprintf(stderr, "sendto error: %s\n", strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ fflush(stdout);
+ }
+
+ close (sockfd);
+ return EXIT_SUCCESS;
+}
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-23 03:32:37 +0000