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authorKristian Lyngstol <kristian@bohemians.org>2016-02-26 10:59:08 +0100
committerKristian Lyngstol <kristian@bohemians.org>2016-02-26 10:59:08 +0100
commit9da864a8da29082369cdd2dd91a735b03577a117 (patch)
tree543d881f3746ddd4805dd0da449783eb42a8a92c /examples/historical/mbd/packetpusher.c
parent9ecc4690b2546ac117204207bec21ee1f6d585cf (diff)
Archive old/unused things
Diffstat (limited to 'examples/historical/mbd/packetpusher.c')
-rw-r--r--examples/historical/mbd/packetpusher.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/examples/historical/mbd/packetpusher.c b/examples/historical/mbd/packetpusher.c
new file mode 100644
index 0000000..c21a084
--- /dev/null
+++ b/examples/historical/mbd/packetpusher.c
@@ -0,0 +1,127 @@
+#include <stdio.h>
+#include <sys/socket.h>
+#include <stdlib.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/udp.h>
+#include <stdint.h>
+#include <arpa/inet.h>
+
+char encoded_pkt[4096], workspace[4096];
+unsigned char pkt[2048];
+
+typedef uint32_t u_int32_t;
+
+u_int32_t checksum(unsigned char *buf, unsigned nbytes, u_int32_t sum)
+{
+ int i;
+ /* Checksum all the pairs of bytes first... */
+ for (i = 0; i < (nbytes & ~1U); i += 2) {
+ sum += (u_int16_t)ntohs(*((u_int16_t *)(buf + i)));
+ if (sum > 0xFFFF)
+ sum -= 0xFFFF;
+ }
+
+ /*
+ * If there's a single byte left over, checksum it, too.
+ * Network byte order is big-endian, so the remaining byte is
+ * the high byte.
+ */
+
+ if (i < nbytes) {
+ sum += buf[i] << 8;
+ if (sum > 0xFFFF)
+ sum -= 0xFFFF;
+ }
+
+ return (sum);
+}
+
+u_int32_t wrapsum(u_int32_t sum)
+{
+ sum = ~sum & 0xFFFF;
+ return (htons(sum));
+}
+
+int main(int argc, char **argv)
+{
+ int sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
+ if (sock == -1) {
+ perror("socket");
+ exit(1);
+ }
+
+ for ( ;; ) {
+ int num_pkts;
+ int ret = scanf("%d %s", &num_pkts, encoded_pkt);
+ if (ret != 2) {
+ fprintf(stderr, "error parsing! ret=%d\n", ret);
+ exit(1);
+ }
+ if ((strlen(encoded_pkt) % 2) != 0) {
+ fprintf(stderr, "hex packet has odd length\n");
+ exit(1);
+ }
+
+ // de-hex packet
+ for (int i = 0; i < strlen(encoded_pkt); i += 2) {
+ char c[3];
+ c[0] = encoded_pkt[i];
+ c[1] = encoded_pkt[i + 1];
+ c[2] = 0;
+ int h = strtol(c, NULL, 16);
+ pkt[i / 2] = h;
+ }
+
+ int datalen = strlen(encoded_pkt) / 2;
+
+ for (int i = 0; i < num_pkts; ++i) {
+ char from_ip[256], to_ip[256];
+ int sport, dport;
+ if (scanf("%s %d %s %d", from_ip, &sport, to_ip, &dport) != 4) {
+ fprintf(stderr, "error parsing packet %d!\n", i);
+ exit(1);
+ }
+
+ // IP header
+ struct iphdr *ip = (struct iphdr *)workspace;
+ ip->version = 4;
+ ip->ihl = 5;
+ ip->tos = 0;
+ ip->tot_len = htons(datalen + sizeof(struct iphdr) + sizeof(struct udphdr));
+ ip->id = 0;
+ ip->frag_off = 0;
+ ip->ttl = 64;
+ ip->protocol = 17; // UDP
+ ip->saddr = inet_addr(from_ip);
+ ip->daddr = inet_addr(to_ip);
+ ip->check = 0;
+ ip->check = wrapsum(checksum((unsigned char *)ip, sizeof(*ip), 0));
+
+ // UDP header
+ struct udphdr *udp = (struct udphdr *)(workspace + sizeof(struct iphdr));
+ udp->source = htons(sport);
+ udp->dest = htons(dport);
+ udp->len = htons(datalen + sizeof(struct udphdr));
+ udp->check = 0;
+
+ int sum = checksum((unsigned char *)&ip->saddr, 2 * sizeof(ip->saddr), IPPROTO_UDP + ntohs(udp->len));
+ sum = checksum((unsigned char *)pkt, datalen, sum);
+ sum = checksum((unsigned char *)udp, sizeof(*udp), sum);
+ udp->check = wrapsum(sum);
+
+ // Data
+ memcpy(workspace + sizeof(struct iphdr) + sizeof(struct udphdr),
+ pkt, datalen);
+
+ // Send out the packet physically
+ struct sockaddr_in to;
+ to.sin_family = AF_INET;
+ to.sin_addr.s_addr = inet_addr(to_ip);
+ to.sin_port = htons(dport);
+
+ sendto(sock, workspace, ntohs(ip->tot_len), 0, (struct sockaddr *)&to, sizeof(to));
+ }
+ }
+}