summaryrefslogtreecommitdiff
path: root/pcap2tzsp.c
diff options
context:
space:
mode:
Diffstat (limited to 'pcap2tzsp.c')
-rw-r--r--pcap2tzsp.c153
1 files changed, 105 insertions, 48 deletions
diff --git a/pcap2tzsp.c b/pcap2tzsp.c
index 16b6e56..656e84a 100644
--- a/pcap2tzsp.c
+++ b/pcap2tzsp.c
@@ -55,6 +55,9 @@ TODO List
SOCKET make_dgram_socket(char host[], char service[], int hint_flags, char **resolved_address);
void start_capture_loop(char *pcap_filter);
void process_packet(u_char *void_args, const struct pcap_pkthdr* pkthdr, const u_char * packet);
+void make_tzsp_notags(u_char *out_tzsp, size_t *tzsplen, const u_char *pdu, size_t pdu_len);
+void make_tzsp_basic(u_char *out_tzsp, size_t *tzsplen, const u_char *pdu, size_t pdu_len, time_t original_packet_timestamp, size_t original_packet_len );
+
/* Custom types definition */
typedef struct _process_packet_args {
@@ -299,7 +302,7 @@ void start_capture_loop(char *pcap_filter) {
if (opt_iface == NULL) {
/* Get the name of the first device suitable for capture */
if ( (pcap_device = pcap_lookupdev(pcap_errbuf)) == NULL){
- fprintf(stderr, "ERROR: %s\n", pcap_errbuf);
+ fprintf(stderr, "ERROR: %s (maybe you forget start this as root)\n", pcap_errbuf);
exit(20);
}
} else {
@@ -389,13 +392,11 @@ void process_packet(u_char *void_args, const struct pcap_pkthdr* pkthdr, const u
static time_t old_tv_sec=0;
static u_int old_captured_pkt_count=0;
- int res, tzsp_len;
+ int res;
+ size_t tzsp_len;
double throughput;
- /*uint32_t pkt_num; // In network byte order */
- uint32_t field_ts; /* In network byte order */
- uint16_t field_len; /* In network byte order */
- char buf[UDP_SEND_BUFLEN];
+ u_char buf[UDP_SEND_BUFLEN];
/* struct timespec ts_reqsleep; // For simulation */
process_packet_args_t *args=(process_packet_args_t *)void_args;
@@ -416,58 +417,114 @@ void process_packet(u_char *void_args, const struct pcap_pkthdr* pkthdr, const u
//TODO : bwlimit HERE (not before, not after)
- /* Variable fields for TZSP packet */
- field_ts=htonl((uint32_t) pkthdr->ts.tv_sec); /* TODO : this cast is bullshit ? */
- field_len=htons((uint16_t) pkthdr->len);
- //pkt_num=htons((uint32_t) args->captured_pkt_count);
-
/* TaZmen Sniffing Protocol (TZSP) packet forging */
+ tzsp_len=UDP_SEND_BUFLEN;
+ switch(0) { /* TODO */
+ case 1:
+ make_tzsp_notags(buf, &tzsp_len,packet,pkthdr->caplen);
+ break;
+ default:
+ make_tzsp_basic(buf, &tzsp_len,packet,pkthdr->caplen, pkthdr->ts.tv_sec, pkthdr->len);
+ }
+ if (tzsp_len < 0) {
+ fprintf(stderr, "make_tzsp_*() problem\n");
+ return;
+ }
- //memset((char *) &buf, 0, UDP_SEND_BUFLEN); /* Buffer reset not useful for now */
- buf[0]=0x01; /* Version */
- buf[1]=0x01; /* Type == Packet for transmit */
- buf[2]=0x00; /* Encapsuled protocol (2 bytes) 0x0001 == Ethernet */
- buf[3]=0x01;
+ /* TZSP packet sending (over the UDP socket) */
- buf[4]=0x0D; /* Tag type == TAG_TIMESTAMP */
- buf[5]=0x04; /* Tag length == 4 bytes */
+ /* Slow sending simulation
+ ts_reqsleep.tv_sec=0;
+ ts_reqsleep.tv_nsec=10000;
+ nanosleep(&ts_reqsleep, NULL);
+ */
+#ifdef WIN32
+ res=send(args->socket, buf, tzsp_len, 0);
+#else
+ res=write(args->socket, buf, tzsp_len);
+#endif
+ if (res != tzsp_len) {
+ fprintf(stderr, "write() on UDP socket error (written %i of %zu bytes)\n", res, tzsp_len);
+ return;
+ }
+
+ args->sent_pkt_count++;
+}
- /* buf[6,7,8,9] Timestamp on 4 bytes (network order) */
- memcpy(buf+6, &field_ts, 4);
+void make_tzsp_notags(u_char *out_tzsp, size_t *tzsplen, const u_char *pdu, size_t pdu_len) {
+ const char tzsp_header_tpl[] = {
+ 0x01, /* Version 1 */
+ 0x01, /* Type : Packet for transmit */
+ 0x00, 0x01, /* Encapsulated protocol : 0x001 == Ethernet */
+ 0x01 /* Tag type : TAG END */
+ };
+ const size_t tzsp_header_len = sizeof(tzsp_header_tpl);
+ size_t needed = tzsp_header_len + pdu_len;
+
+ /* Check if enought space in out buffer */
+ if ( *tzsplen < needed ) {
+ *tzsplen=-1;
+ return;
+ }
- /* Wireshark don't dissect that */
- //buf[10]=0x28; /* Tag type TAG_PACKET_COUNT */
- //buf[11]=0x04; /* Tag length == 4 bytes */
- //memcpy(buf+12,&pkt_num, 4);
+ /* Header copy */
+ memcpy(out_tzsp, tzsp_header_tpl, tzsp_header_len);
- buf[10]=0x29; /* Tag type TAG_RX_FRAME_LENGTH */
- buf[11]=0x02; /* Tag length == 2 bytes */
- memcpy(buf+12, &field_len, 2);
+ /* Raw packet copy */
+ memcpy(out_tzsp + tzsp_header_len, pdu, pdu_len);
- buf[14]=0x00; /* Tag type TAG PADDING (for alignement) */
- buf[15]=0x01; /* Tag type TAG END */
+ /* Update tzsplen to the effecive len */
+ *tzsplen=needed;
- /* Raw packet copy */
- //TODO : assert that pkthdr->caplen < MAX_TZSP_PAYLOAD
- memcpy(buf+16,packet, pkthdr->caplen);
+ return;
+}
- /* TZSP packet sending (over the UDP socket) */
- tzsp_len=16+pkthdr->caplen;
-#ifdef WIN32
- res=send(args->socket, buf, tzsp_len,0);
-#else
- res=write(args->socket, buf, tzsp_len);
-#endif
- if (res != tzsp_len) {
- fprintf(stderr, "write() on UDP socket error (written %i of %i bytes)\n", res, tzsp_len);
- } else {
- args->sent_pkt_count++;
+void make_tzsp_basic(u_char *out_tzsp, size_t *tzsplen, const u_char *pdu, size_t pdu_len, time_t original_packet_timestamp, size_t original_packet_len ) {
+ const char tzsp_header_tpl[] = {
+ 0x01, /* Version 1 */
+ 0x01, /* Type : 0x01 == Packet for transmit */
+ 0x00, 0x01, /* Encapsulated protocol : 0x0001 == Ethernet */
+
+ 0x0D, /* Tag type TAG_TIMESTAMP */
+ 0x04, /* Tag len : 4 bytes */
+ 0x00, 0x00, 0x00, 0x00, /* Tag Value (placeholder) */
+
+ 0x29, /* Tag type TAG_RX_FRAME_LENGTH */
+ 0x02, /* Tag len : 2 bytes */
+ 0x00, 0x00, /* Tag Value (placeholder) */
+
+ 0x00, /* Tag type : TAG PADDING (for alignement) */
+ 0x01 /* Tag type : TAG END */
+ };
+ const size_t tzsp_header_len = sizeof(tzsp_header_tpl);
+ uint32_t tag_timestamp_value;
+ uint16_t tag_packet_len_value;
+ size_t needed;
+
+ /* Check if enough space in out buffer */
+ needed = tzsp_header_len + pdu_len;
+ if ( *tzsplen < needed ) {
+ *tzsplen=-1;
+ return;
}
- /* Slow sending simulation
- ts_reqsleep.tv_sec=0;
- ts_reqsleep.tv_nsec=10000;
- nanosleep(&ts_reqsleep, NULL);
- */
+ /* "Compute" tags values (network byte order) */
+ tag_timestamp_value=htonl((uint32_t) original_packet_timestamp);
+ tag_packet_len_value=htons((uint16_t) original_packet_len);
+
+ /* Header template copy */
+ memcpy(out_tzsp, tzsp_header_tpl, tzsp_header_len);
+
+ /* Tag values copy */
+ memcpy(out_tzsp+6, &tag_timestamp_value, sizeof(uint32_t));
+ memcpy(out_tzsp+12, &tag_packet_len_value, sizeof(uint16_t));
+
+ /* Raw packet copy */
+ memcpy(out_tzsp + tzsp_header_len, pdu, pdu_len);
+
+ /* Update tzsplen to the effecive len */
+ *tzsplen=needed;
+
+ return;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 02:38:14 +0000