Merge pull request #4 from Mosder/2-simple-capturing-mode

Simple capturing mode

11 files changed, 308 insertions, 4 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..dc2bf7f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+compile_commands.json
+sample_data/
+analyzer/headers/server.h
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..a85df64
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,16 @@
+global: compile
+	sudo mv branal /usr/bin
+
+local: compile
+	mv branal ${HOME}/.local/bin
+
+compile: utils capture
+	gcc *.o main.c -o branal
+	rm *.o
+
+utils:
+	gcc -c analyzer/utils/fs.c
+	gcc -c analyzer/utils/time.c
+
+capture:
+	gcc -c analyzer/capture.c
diff --git a/README.md b/README.md
index 7d64ae9..780548b 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,102 @@
-# A (to be) bare-bones analyzer for the game Broken Ranks
+# A bare-bones analyzer for the game Broken Ranks
 
-Yet to be implemented, analyzer for the game Broken Ranks.
-Inspired by [BrokenHUD](https://github.com/Brok3nSign/BrokenTools/releases).
-Will definitely be way more primitive than the one it's inspired on, because I just can't be bothered to add all those features.
+Inspired by [BrokenHUD](https://github.com/Brok3nSign/BrokenTools/releases).  
+Way more primitive than the one it's inspired by, because I just can't be bothered to add all those features.  
 Unless you value FOSS or have troubles setting up BrokenHUD on your linux system, then you should use [it](https://github.com/Brok3nSign/BrokenTools/releases) instead.
+
+## Features
+- Capturing packets sent by the game and saving them to a file for later use
+
+### Planned features
+- Analyzer for the `.pcap` files containing captured packets:
+  - List of fight results in the given file with rewards gained for each player
+  - Total gained rewards in all fights in the given file
+- Live analyzer parsing packets in real time:
+  - Results of the last fight
+  - Total gained rewards, since starting the analyzer
+
+## Getting started
+
+### Prerequisites
+- Base utils: `git`, `gcc`, `make`
+- [tshark](https://tshark.dev/setup/install/#installing-tshark-only)
+
+### Installation
+**1. Clone and enter the repository:**
+```
+git clone https://github.com/Mosder/branal
+cd branal
+```
+
+**2. Create the server header file:**  
+You will need to find out the IP address of the game server.  
+To do so, use [termshark](https://github.com/gcla/termshark) or any other tool you'd prefer.  
+Then, create the file (replace `<ip>` with the IP address you found):
+```
+echo "#define SERVER_IP \"<ip>\"" > analyzer/headers/server.h
+```
+It's not included in the repository to avoid it being scraped by bots or something.
+
+**3. Modify the interface header file:**  
+Right now the used interface is `enp8s0`, which likely isn't the name of your interface.  
+To find the name of your interface, use:
+```
+ip address
+```
+Then, modify the file (replace `<interface>` with your interface name):
+```
+echo "#define INTERFACE \"<interface>\"" > analyzer/headers/interface.h
+```
+
+**4. Compile the code**:  
+Finally, compile the code with `make`.  
+To install it into `/usr/bin`:
+```
+make
+```
+that will use sudo and require password.
+
+You can instead install it into `~/.local/bin`:
+```
+make local
+```
+
+You can also just compile it in place:
+```
+make compile
+```
+and just move the `branal` binary to your preferred directory.
+
+## Usage
+
+### Live analyzer (NOT IMPLEMENTED)
+To start live analyzer, use:
+```
+branal
+```
+or
+```
+branal (l | live)
+```
+It will open the live analyzer in your terminal.
+
+### File analyzer (NOT IMPLEMENTED)
+To analize a `.pcap` file, use:
+```
+branal (f | file) <file>
+```
+It will perform analysis of the specified `<file>`.
+
+### Capturing packets
+To just capture packets from the server, use:
+```
+branal (c | capture) [file]
+```
+It will start capturing packets to the specified `[file]`.  
+If `[file]` is not specified, it will capture them to the default location (`~/.local/share/branal/captures`).
+
+### Help
+You can display help using:
+```
+branal (h | help)
+```
diff --git a/analyzer/capture.c b/analyzer/capture.c
new file mode 100644
index 0000000..0a75e09
--- /dev/null
+++ b/analyzer/capture.c
@@ -0,0 +1,28 @@
+#include "capture.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "headers/interface.h"
+#include "headers/server.h"
+#include "utils/fs.h"
+#include "utils/time.h"
+
+void capture_to_file(char *path) {
+    char command[128];
+    sprintf(command, "tshark -i %s -f \"src host %s\" -w %s", INTERFACE, SERVER_IP, path);
+    system(command);
+}
+
+void capturing_mode(char *path) {
+    if (path != NULL) {
+        capture_to_file(path);
+        return;
+    }
+
+    char capture_dir[256], new_path[256], date_time[128];
+    get_capture_dir(capture_dir);
+    get_date_time_string(date_time);
+    sprintf(new_path, "%s/capture-%s.pcap", capture_dir, date_time);
+    capture_to_file(new_path);
+}
diff --git a/analyzer/capture.h b/analyzer/capture.h
new file mode 100644
index 0000000..648e5ad
--- /dev/null
+++ b/analyzer/capture.h
@@ -0,0 +1,8 @@
+// capture.h
+// functions for capturing packets using tshark
+
+// starts capturing mode
+// params:
+//      - path - file path to capture the .pcap file to,
+//               if NULL, saves it to default capture directory as capture-<date>_<time>.pcap
+extern void capturing_mode(char *path);
diff --git a/analyzer/headers/interface.h b/analyzer/headers/interface.h
new file mode 100644
index 0000000..8b407c4
--- /dev/null
+++ b/analyzer/headers/interface.h
@@ -0,0 +1 @@
+#define INTERFACE "enp8s0"
diff --git a/analyzer/utils/fs.c b/analyzer/utils/fs.c
new file mode 100644
index 0000000..76fb581
--- /dev/null
+++ b/analyzer/utils/fs.c
@@ -0,0 +1,43 @@
+#include "utils.h"
+
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+void get_home_dir(char *home_dir) {
+    strcpy(home_dir, getenv("HOME"));
+}
+
+void get_main_dir(char *main_dir) {
+    char home_dir[256];
+    get_home_dir(home_dir);
+    sprintf(main_dir, "%s/.local/share/branal", home_dir);
+}
+
+void get_capture_dir(char *capture_dir) {
+    char main_dir[256];
+    get_main_dir(main_dir);
+    sprintf(capture_dir, "%s/captures", main_dir);
+}
+
+void get_saves_dir(char *saves_dir) {
+    char main_dir[256];
+    get_main_dir(main_dir);
+    sprintf(saves_dir, "%s/saves", main_dir);
+}
+
+void create_necessary_directories() {
+    char main_dir[256], capture_dir[256], saves_dir[256];
+    get_main_dir(main_dir);
+    get_capture_dir(capture_dir);
+    get_saves_dir(saves_dir);
+    mkdir(main_dir, 0755);
+    mkdir(capture_dir, 0755);
+    mkdir(saves_dir, 0755);
+}
+
+void write_file(char *path, void *contents, int contents_len, int flags, mode_t permissions) {
+    int fd = open(path, flags, permissions);
+    write(fd, contents, contents_len);
+    close(fd);
+}
diff --git a/analyzer/utils/fs.h b/analyzer/utils/fs.h
new file mode 100644
index 0000000..6335799
--- /dev/null
+++ b/analyzer/utils/fs.h
@@ -0,0 +1,31 @@
+// utils/fs.h
+// functions for operating on the file system, i.e. creating directories, writing files, etc.
+
+#include <sys/types.h>
+
+// get main directory used by the program
+// params:
+//      - main_dir - buffer to save the directory to
+extern void get_main_dir(char *main_dir);
+
+// get directory to save the .pcap files to
+// params:
+//      - capture_dir - buffer to save the directory to
+extern void get_capture_dir(char *capture_dir);
+
+// get directory of save data of the program
+// params:
+//      - saves_dir - buffer to save the directory to
+extern void get_saves_dir(char *saves_dir);
+
+// create directories that will be used by the program
+extern void create_necessary_directories();
+
+// writes file to the specified path
+// params:
+//      - path - path to write the file to
+//      - contents - contents of the file
+//      - contents_len - amount of bytes of contents to write
+//      - flags - flags to open the file with
+//      - permissions - permissions of the written file
+extern void write_file(char *path, void *contents, int contents_len, int flags, mode_t permissions);
diff --git a/analyzer/utils/time.c b/analyzer/utils/time.c
new file mode 100644
index 0000000..72c0bc7
--- /dev/null
+++ b/analyzer/utils/time.c
@@ -0,0 +1,10 @@
+#include "time.h"
+
+#include <stdio.h>
+#include <time.h>
+
+void get_date_time_string(char *date_time) {
+    time_t now = time(NULL);
+    struct tm *t = localtime(&now);
+    sprintf(date_time, "%02d%02d%02d_%02d%02d%02d", t->tm_year - 100, t->tm_mon + 1, t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec);
+}
diff --git a/analyzer/utils/time.h b/analyzer/utils/time.h
new file mode 100644
index 0000000..0bd0df1
--- /dev/null
+++ b/analyzer/utils/time.h
@@ -0,0 +1,7 @@
+// utils/time.h
+// functions regarding date and time
+
+// gets a string <date>_<time> for current localtime
+// params:
+//      date_time - buffer to save the datetime string to
+extern void get_date_time_string(char *date_time);
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..456b590
--- /dev/null
+++ b/main.c
@@ -0,0 +1,61 @@
+#include <stdio.h>
+#include <string.h>
+
+#include "analyzer/capture.h"
+#include "analyzer/utils/fs.h"
+
+// prints help
+void print_help() {
+    printf("A bare-bones analyzer for the game Broken Ranks\n");
+    printf("\nUsage:\n");
+    printf("  branal                      - start live analysis\n");
+    printf("  branal (l | live)           - start live analysis (same as above)\n");
+    printf("  branal (c | capture) [file] - start capturing packets to [file].\n");
+    printf("                                If [file] not given - captures to $HOME/.local/share/branal/captures\n");
+    printf("  branal (f | file) <file>    - analyze the specified <file>\n");
+    printf("  branal (h | help)           - display this help\n");
+}
+
+// starts live analyzer mode
+void start_live_analyzer() {
+    // TODO: implement
+    printf("Not implemented\n");
+}
+
+// analyzes the specified file
+// params:
+// 	- file_path - path to the .pcap file to be analyzed
+void analyze_file(char *file_path) {
+    // TODO: implement
+    printf("Not implemented\n");
+}
+
+int main(int argc, char *argv[]) {
+    create_necessary_directories();
+
+    // start live analysis if no arguments provided
+    if (argc < 2) {
+        start_live_analyzer();
+        return 0;
+    }
+
+    if (strcmp("l", argv[1]) == 0 || strcmp("live", argv[1]) == 0) {
+        start_live_analyzer();
+    }
+    else if (strcmp("c", argv[1]) == 0 || strcmp("capture", argv[1]) == 0) {
+        capturing_mode(argc >= 3 ? argv[2] : NULL);
+    }
+    else if (strcmp("h", argv[1]) == 0 || strcmp("help", argv[1]) == 0) {
+        print_help();
+    }
+    else if (argc >= 3 && (strcmp("f", argv[1]) == 0 || strcmp("file", argv[1]) == 0)) {
+        analyze_file(argv[2]);
+    }
+    else {
+        printf("Command not recognized\n");
+        printf("Use \"branal (h | help)\" for help\n");
+        return 1;
+    }
+
+    return 0;
+}