feat: added basic structures for fight results parsing and base functionallity of finding only the necessary data. Still need to do tcp stream reassembly and the actual parsing of the data.

8 files changed, 173 insertions, 13 deletions

diff --git a/Makefile b/Makefile
index d0a760e..f298b4d 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@ global: compile
 local: compile
 	mv branal ${HOME}/.local/bin
 
-compile: utils capture analyzer
+compile: utils capture analyzer parser
 	gcc *.o main.c -lpcap -o branal
 	rm *.o
 
@@ -19,4 +19,8 @@ capture:
 analyzer:
 	gcc -c analyzer/analyzer.c
 
+parser:
+	gcc -c analyzer/parser/parser.c
+	gcc -c analyzer/parser/fight_results.c
+
 .PHONY: analyzer
diff --git a/analyzer/analyzer.c b/analyzer/analyzer.c
index 7790f41..acbd5de 100644
--- a/analyzer/analyzer.c
+++ b/analyzer/analyzer.c
@@ -1,7 +1,6 @@
 #include "analyzer.h"
 
-#include <unistd.h>
-
+#include "parser/parser.h"
 #include "utils/pcap.h"
 
 void analyze_file(char *path) {
@@ -22,14 +21,11 @@ void analyze_file(char *path) {
     // read packets from the file
     while (pcap_next_ex(handle, &packet_data, &packet) == 1) {
         int payload_len;
-        payload = get_payload_from_packet(packet, packet_data, &payload_len);
-        if (payload_len > 0) {
-            printf("\n----------------\n");
-            printf("Payload length: %d\n", payload_len);
-            printf("Payload:\n");
-            fflush(stdout);
-            write(STDOUT_FILENO, payload, payload_len);
-        }
+        uint32_t tcp_seq;
+        payload = get_payload_from_packet(packet, packet_data, &payload_len, &tcp_seq);
+        // TODO: Stream reassembly using TCP sequence number
+        int parsed_len;
+        parse_stream((char *)payload, payload_len, &parsed_len);
     }
 
     pcap_close(handle);
diff --git a/analyzer/parser/fight_results.c b/analyzer/parser/fight_results.c
new file mode 100644
index 0000000..c6ad7cc
--- /dev/null
+++ b/analyzer/parser/fight_results.c
@@ -0,0 +1,18 @@
+#include "fight_results.h"
+
+#include <stdio.h>
+#include <string.h>
+
+char *find_fight_results(char *stream, int stream_len, int *length) {
+    char *start = memmem(stream, stream_len, FIGHT_RESULTS_START, strlen(FIGHT_RESULTS_START));
+    char *end = memmem(stream, stream_len, FIGHT_RESULTS_END, strlen(FIGHT_RESULTS_END));
+    *length = start != NULL && end != NULL ? end - start + strlen(FIGHT_RESULTS_END) : -1;
+    return start;
+}
+
+FightResults parse_fight_results(char *data, int length) {
+    // TODO: actually parse that data
+    printf("len=%d\n%.*s\n----------------\n", length, length, data);
+    FightResults tmp;
+    return tmp;
+}
diff --git a/analyzer/parser/fight_results.h b/analyzer/parser/fight_results.h
new file mode 100644
index 0000000..270aba8
--- /dev/null
+++ b/analyzer/parser/fight_results.h
@@ -0,0 +1,102 @@
+// parser/fight_results.h
+// utilities for parsing the fight results data
+
+// Payload structure:
+// FIGHT_RESULTS_START EntityResults (SEPARATOR_ENTITY EntityResults)* FIGHT_RESULTS_END
+//
+// EntityResults structure:
+// field (SEPARATOR_RESULT field)*
+// fields are defined in order in the EntityResults struct
+
+#define FIGHT_RESULTS_START "3;19;"
+#define FIGHT_RESULTS_END "[--];"
+#define SEPARATOR_ENTITY "[--]"
+#define SEPARATOR_RESULT "&"
+
+typedef struct {
+    int team; // friend or enemy
+    char *name;
+    int exp;
+    float field4;
+    int gold;
+    float field6;
+    char *field7;
+    char *gear; // rares, sets, syngs, orbs
+    int field9;
+    char *items; // regular items
+    int field11;
+    int field12;
+    float field13;
+    float field14; // some multiplier most likely exp/gold/psycho/something else idk
+    float field15;
+    int level;
+    double field17;
+    float field18;
+    int field19;
+    int field20;
+    float field21;
+    float field22;
+    int field23;
+    int field24;
+    int psycho;
+    char *drifs;
+    int splinters;
+    int field28;
+    char *field29;
+    int field30;
+    int field31; // possibly information who is the player - 1 for current player, 0 for others (need to double check)
+    int field32;
+    int field33;
+    char *field34;
+    char *saturation;
+} EntityResults;
+
+// values of field "team"
+#define TEAM_FRIEND 1
+#define TEAM_ENEMY 2
+
+// fight results data for friendly
+typedef struct {
+    char *name;
+    int exp;
+    int gold;
+    char *gear;
+    char *items;
+    int level;
+    int psycho;
+    char *drifs;
+    int splinters;
+    char *saturation_type;
+    int saturation;
+} FriendlyResults;
+
+// fight results data for enemy
+typedef struct {
+    char *name;
+    int level;
+} EnemyResults;
+
+// entire fight resutls
+typedef struct {
+    int num_friendly;
+    FriendlyResults *friendly_results;
+    int num_enemy;
+    EnemyResults *enemy_results;
+} FightResults;
+
+// find the first fight results data in stream
+// params:
+//      - stream - stream to find the fight results in
+//      - stream_len - length of the stream
+//      - length - length of the fight results data or -1 if there's no end yet
+// returns:
+//      pointer to the beggining of fight results data or NULL if there's none
+extern char *find_fight_results(char *stream, int stream_len, int *length);
+
+// parse given fight results
+// params:
+//      - data - fight results data to parse
+//      - length - length of fight results data
+// returns:
+//      FightResults struct containing parsed data
+extern FightResults parse_fight_results(char *data, int length);
diff --git a/analyzer/parser/parser.c b/analyzer/parser/parser.c
new file mode 100644
index 0000000..b551d8e
--- /dev/null
+++ b/analyzer/parser/parser.c
@@ -0,0 +1,15 @@
+#include "parser.h"
+
+#include <stdlib.h>
+
+ParsedData *parse_stream(char *stream, int stream_len, int *parsed_len) {
+    // TODO: Need to do parsing of the entire thing (loop) and return all of the parsed data
+    if (stream_len > 0) {
+        int length;
+        char *start = find_fight_results(stream, stream_len, &length);
+        if (start != NULL) {
+            parse_fight_results(start, length);
+        }
+    }
+    return NULL;
+}
diff --git a/analyzer/parser/parser.h b/analyzer/parser/parser.h
new file mode 100644
index 0000000..18b4b83
--- /dev/null
+++ b/analyzer/parser/parser.h
@@ -0,0 +1,21 @@
+// parser/parser.h
+// main parser file
+
+#include "fight_results.h"
+
+// "generic" type for parsed data
+typedef struct {
+    enum { FIGHT_RESULTS } data_type;
+    union {
+        FightResults fight_results;
+    } data;
+} ParsedData;
+
+// parse a stream of TCP data
+// params:
+//      - stream - the stream to parse
+//      - stream_len - length of the stream to parse
+//      - parsed_len - pointer to inform how much of the stream was parsed (not all if e.g. start of data is there, but the end isn't yet)
+// returns:
+//      pointer to the array of parsed data
+extern ParsedData *parse_stream(char *stream, int stream_len, int *parsed_len);
diff --git a/analyzer/utils/pcap.c b/analyzer/utils/pcap.c
index cdefba7..5e9b611 100644
--- a/analyzer/utils/pcap.c
+++ b/analyzer/utils/pcap.c
@@ -4,7 +4,7 @@
 #include <netinet/ip.h>
 #include <netinet/tcp.h>
 
-const unsigned char *get_payload_from_packet(const unsigned char *packet, const struct pcap_pkthdr *packet_data, int *payload_len) {
+const unsigned char *get_payload_from_packet(const unsigned char *packet, const struct pcap_pkthdr *packet_data, int *payload_len, uint32_t *tcp_seq) {
     // get Ethernet header
     const struct ether_header *eth_header = (const struct ether_header *)packet;
     int eth_header_len = sizeof(struct ether_header);
@@ -29,6 +29,9 @@ const unsigned char *get_payload_from_packet(const unsigned char *packet, const
     const struct tcphdr *tcp_header = (const struct tcphdr *)(packet + eth_header_len + ip_header_len);
     int tcp_header_len = tcp_header->th_off * 4;
 
+    // get TCP sequence number
+    *tcp_seq = ntohl(tcp_header->seq);
+
     // get payload
     int total_header_len = eth_header_len + ip_header_len + tcp_header_len;
     *payload_len = packet_data->caplen - total_header_len;
diff --git a/analyzer/utils/pcap.h b/analyzer/utils/pcap.h
index d31b961..16da7cd 100644
--- a/analyzer/utils/pcap.h
+++ b/analyzer/utils/pcap.h
@@ -8,6 +8,7 @@
 //      - packet - captured packet
 //      - packet_data - metadata about packet
 //      - payload_len - pointer to save the payload length to or -1 if not a correct packet
+//      - tcp_seq - pointer to save the TCP sequence number
 // returns:
 //      pointer to the payload or NULL if not a correct packet
-extern const unsigned char *get_payload_from_packet(const unsigned char *packet, const struct pcap_pkthdr *packet_data, int *payload_len);
+extern const unsigned char *get_payload_from_packet(const unsigned char *packet, const struct pcap_pkthdr *packet_data, int *payload_len, uint32_t *tcp_seq);