Add server with challenges

Co-authored-by: Ezequiel Bellver <ebellver@itba.edu.ar>
Co-authored-by: Juan Barmasch <jbarmasch@itba.edu.ar>

.gitignore

@@ -0,0 +1,8 @@
+.bash_history
+.bashrc
+.config/
+.gdb_history
+.gdbinit
+.idea/
+.inputrc
+.viminfo

.vscode/settings.json

@@ -2,6 +2,8 @@
     "files.associations": {
         "error.h": "c",
         "client.h": "c",
-        "errors.h": "c"
+        "errors.h": "c",
+        "server.h": "c",
+        "challenges.h": "c"
     }
 }

Makefile

@@ -1,19 +1,25 @@
 CC = gcc
 CCFLAGS = -Wall -std=c99 -pedantic -g
 
-OBJECTS = server.o errors.o client.o 
+# OBJECTS = errors.o server.o client.o 
 
-all: $(OBJECTS)
+CLIENT=client.o
+SERVER=server.o
+ERROR=errors.o
+CHALLENGE=challenges.o
 
-server.o: server.c include/errors.h
-	$(CC) $(CCFLAGS) -c server.c
-errors.o: errors.c include/errors.h
-	$(CC) $(CCFLAGS) -c errors.c
-client.o: client.c errors.o
-	$(CC) $(CCFLAGS) client.c -o client.o errors.o
+all: $(ERROR) $(CHALLENGE) $(CLIENT) $(SERVER)
+
+$(SERVER):
+	$(CC) $(CCFLAGS) server.c -o server challenges.o errors.o
+$(CLIENT):
+	$(CC) $(CCFLAGS) client.c -o client errors.o
+
+%.o: %.c
+	$(CC) $(CCFLAGS) -I./include -c $<
 
 clean:
-	rm -rf $(OBJECTS)
+	rm -rf $(ERROR) $(CHALLENGE) $(CLIENT) $(SERVER) server client
 
 test:
 	pvs-studio-analyzer trace -- make

challenges.c

@@ -0,0 +1,47 @@
+#include "include/challenges.h"
+
+// char introChallenge(int fd, char * output, char * message, char * question, char * flag) {
+//     printf("%s\n", message);
+    
+//     int readChars;
+//     while ((readChars = read(fd, output, MAX_LEN - 1)) != 0) {
+//         if (readChars < 0)
+//             printSystemError("Challenges: read()");
+//         output[readChars] = '\0';
+//     }
+
+//     printf("%s\n", question);
+
+//     return strcmp(output, flag) == 0;
+// }
+
+// char genChallenge(int fd, char * output, char * message, char * question, char * flag) {
+//     printf("%s\n", message);
+    
+//     int readChars;
+//     while ((readChars = read(fd, output, MAX_LEN - 1)) != 0) {
+//         if (readChars < 0)
+//             printSystemError("Challenges: read()");
+//         output[readChars] = '\0';
+//     }
+
+//     printf("%s\n", question);
+
+//     return !strcmp(output, flag);
+// }
+
+char genChallenge(int fd, char * output, challenge_t challenge) {
+    printf("%s\n", challenge.message);
+    
+    int readChars;
+    // while ((readChars = read(fd, output, MAX_LEN - 1)) != 0) {
+    readChars = read(fd, output, MAX_LEN - 1);
+        if (readChars < 0)
+            printSystemError("Challenges: read()");
+        output[readChars] = '\0';
+    // }
+
+    printf("%s\n", challenge.question);
+
+    return strcmp(output, challenge.flag);
+}

client.c

@@ -2,19 +2,16 @@
 
 int main(int argc, char *argv[]) {
     int fd = 0;
-    struct sockaddr_in serv_addr;
-
-    if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
+    if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
         printSystemError("User: socket()");
-    }
    
+    struct sockaddr_in serv_addr;
     serv_addr.sin_family = AF_INET;
     serv_addr.sin_port = htons(PORT);
     serv_addr.sin_addr.s_addr = inet_addr(ADDRESS);
 
-    if (connect(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
+    if (connect(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
         printSystemError("User: connect()");
-    }
 
     char input[MAX_LEN] = {0};
     int readChars;
@@ -23,9 +20,8 @@ int main(int argc, char *argv[]) {
             printSystemError("User: read()");
         input[readChars] = '\0';
 
-        if (write(fd, input, readChars) < 0) {
+        if (write(fd, input, readChars) < 0)
             printSystemError("User: write()");
-        }
     }
 
     close(fd);

include/challenges.h

@@ -0,0 +1,22 @@
+#ifndef CHALLENGES_H 
+#define CHALLENGES_H 
+
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include "errors.h"
+
+#define MAX_LEN 100
+
+typedef struct challenge_t {
+    // char (* challenge) (int fd, char * output, char * message, char * question, char * flag);
+    char * message;
+    char * question;
+    char * flag;
+} challenge_t;
+
+// char genChallenge(int fd, char * output, char * message, char * question, char * flag);
+char genChallenge(int fd, char * output, challenge_t challenge);
+
+#endif

include/client.h

@@ -9,7 +9,6 @@
 #include <stdlib.h>
 #include "errors.h"
 
-#define MAX_ARGS 3
 #define MAX_LEN 100
 #define PORT 8080
 #define ADDRESS "127.0.0.1"

include/server.h

@@ -0,0 +1,23 @@
+#ifndef SERVER_H
+#define SERVER_H
+
+#include <stdio.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include "errors.h"
+#include <netinet/in.h>
+#include "challenges.h"
+
+#define MAX_LEN 100
+#define PORT 8080
+#define ADDRESS "127.0.0.1"
+#define MAX_PEND_REQ 3
+#define MAX_CHALLENGES 2
+#define TIME_SLEEP 2
+
+void startChallenge();
+
+#endif

server.c

@@ -0,0 +1,60 @@
+#include "include/server.h"
+
+int clientFd;
+
+challenge_t challenges[] = {
+    {"A volar bobby", "Cómo es que matan?", "IZPUAN"},
+    {"A cagar bobby", "A una niña", "PUANIZ"}
+};
+
+int main(int argc, char *argv[]) {
+    int fd;
+    if ((fd = socket(AF_INET, SOCK_STREAM, 0)) == 0)
+        printSystemError("Server: socket()");
+       
+    int opt = 1;
+    if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)))
+        printSystemError("Server: setsockopt()");
+
+    struct sockaddr_in address;
+    address.sin_family = AF_INET;
+    // address.sin_addr.s_addr = INADDR_ANY;
+    address.sin_addr.s_addr = inet_addr(ADDRESS);
+    address.sin_port = htons(PORT);
+       
+    if (bind(fd, (struct sockaddr *) &address, sizeof(address)) < 0) 
+        printSystemError("Server: bind()");
+
+    if (listen(fd, MAX_PEND_REQ) < 0)
+        printSystemError("Server: listen()");
+
+    int addrlen = sizeof(address);
+    if ((clientFd = accept(fd, (struct sockaddr *) &address, (socklen_t *) &addrlen)) < 0)
+        printSystemError("Server: accept()");
+
+    startChallenge();
+
+    close(clientFd);
+    close(fd);
+
+    return EXIT_SUCCESS;
+}
+
+void startChallenge() {
+    int challengeCount = 0;
+    char ansChallenge = 1, output[MAX_LEN] = {0};
+
+    while (challengeCount < MAX_CHALLENGES && ansChallenge) {
+        challenge_t currentChallenge = challenges[challengeCount];
+        printf("\033[1;1H\033[2J"); // Limpiamos shell
+        if ((ansChallenge = genChallenge(clientFd, output, currentChallenge))) {
+            challengeCount++;
+        }
+        else {
+            printf("Incorrecta\n");
+            sleep(TIME_SLEEP);
+        }
+    }
+
+    return;
+}