Started writing the management program.

.gitignore

@@ -0,0 +1 @@
+[bB]in/

Makefile

@@ -0,0 +1,28 @@
+# ---- ---- #
+
+CC = clang
+CF = -Wall -lkrb5 -lvirt -ljson-c -g
+
+# ---- ---- #
+
+build: $(shell find . -name "*.c") $(shell find . -name "*.h")
+	@echo "Building sandbox..."
+	@mkdir -p bin
+	@$(CC) $(CF) -o ./bin/sandbox $(shell find . -name "*.c")
+
+run: build
+	@echo "Running sandbox..."
+	@./bin/sandbox
+
+debug: build
+	@echo "Debugging sandbox..."
+	@gdb -q ./bin/sandbox
+
+clean:
+	@echo "Cleaning sandbox..."
+	@rm -rf ./bin
+
+.PHONY: build run clean
+
+# ---- ---- #
+

src/backing.c

@@ -0,0 +1,66 @@
+#include "backing.h"
+
+#include "utils.h"
+#include "sandbox.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+char* get_backings_path(void) {
+	return format("%s/%s", MASTER_DIRECTORY, BACKINGS_DIRECTORY);
+}
+
+bool is_valid_backing_name(const char* name) {
+	if (name == NULL)
+		return false;
+
+	// Check that the name is not empty
+	size_t length = strlen(name);
+	if (length == 0)
+		return false;
+
+	// Check that the name is a number (the number is the timestamp of the backing disk creation)
+	for (size_t i = 0; i < length; i++)
+		if (name[i] < '0' || name[i] > '9')
+			return false;
+
+	return true;
+}
+
+char* get_backing_path(const char* backing) {
+	char* backings_path = get_backings_path();
+	if (backings_path == NULL)
+		return NULL;
+
+	// Combine the backings path with the backing name
+	char* backing_path = format("%s/%s", backings_path, backing);
+
+	// Free the backings path
+	free(backings_path);
+
+	return backing_path;
+}
+
+bool backing_exists(const char* backing) {
+	char* backing_path = get_backing_path(backing);
+	if (backing_path == NULL)
+		return false;
+
+	// Check if the backing path exists
+	struct stat statbuf;
+	int result = stat(backing_path, &statbuf);
+
+	// Free the backing path
+	free(backing_path);
+
+	if (result != 0)
+		return false;
+
+	if (!S_ISREG(statbuf.st_mode))
+		return false;
+
+	return true;
+}

src/backing.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/// @brief Returns the directory path where the backing disks are stored.
+/// @return The directory path where the backing disks are stored. The caller is responsible for freeing the returned string. This function can return NULL.
+char* get_backings_path(void);
+
+/// @brief Checks if the specified backing disk name is valid.
+/// @param name The backing disk name to check.
+/// @return true if the backing disk name is valid, otherwise false.
+bool is_valid_backing_name(const char* name);
+
+/// @brief Returns the path to the specified backing disk.
+/// @param backing The valid backing disk name.
+/// @return The path to the specified backing disk. The caller is responsible for freeing the returned string. This function can return NULL.
+char* get_backing_path(const char* backing);
+
+/// @brief Checks if the specified backing disk exists.
+/// @param backing The valid backing disk name.
+/// @return true if the backing disk exists, otherwise false.
+bool backing_exists(const char* backing);
+
+/// @brief Lists the backing disks.
+/// @return The list of backing disks. The caller is responsible for freeing the returned array and strings. This function can return NULL.
+char** list_backings(void);
+
+/// @brief Creates a new backing disk.
+/// @param backing_disk The disk to use as the backing disk. Warning: the disk must be part of the backing disks.
+/// @return true if the backing disk was created, otherwise false.
+bool create_backing(const char* backing_disk);

src/disk.c

@@ -0,0 +1,121 @@
+#include "disk.h"
+
+#include "utils.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <json-c/json.h>
+
+bool create_empty_disk(const char* disk, uint64_t size) {
+	char* stdoutb = NULL;
+	char* stderrb = NULL;
+
+	// Create an empty disk
+	int result = execute(&stdoutb, &stderrb, "qemu-img", "create", "-c", "-f", "qcow2", disk, format("%lu", size), NULL);
+
+	// Check if the command was successful
+	if (result != 0) {
+		// Remove the newline character from the stderr buffer
+		size_t length = strlen(stderrb);
+		for (size_t i = 0; i < length; i++)
+			if (stderrb[i] == '\n')
+				stderrb[i] = ' ';
+		log_msg(LOG_ERROR, "Failed to create the empty disk %s (%s)", disk, stderrb);
+
+		free(stdoutb);
+		free(stderrb);
+
+		return false;
+	}
+
+	free(stdoutb);
+	free(stderrb);
+
+	return true;
+}
+
+bool create_backed_disk(const char* disk, const char* backing) {
+	char* stdoutb = NULL;
+	char* stderrb = NULL;
+
+	// Create a backed disk
+	int result = execute(&stdoutb, &stderrb, "qemu-img", "create", "-c", "-f", "qcow2", "-F", "qcow2", "-b", backing, disk, NULL);
+
+	// Check if the command was successful
+	if (result != 0) {
+		// Remove the newline character from the stderr buffer
+		size_t length = strlen(stderrb);
+		for (size_t i = 0; i < length; i++)
+			if (stderrb[i] == '\n')
+				stderrb[i] = ' ';
+		log_msg(LOG_ERROR, "Failed to create the backed disk %s (%s)", disk, stderrb);
+
+		free(stdoutb);
+		free(stderrb);
+
+		return false;
+	}
+
+	free(stdoutb);
+	free(stderrb);
+
+	return true;
+}
+
+char* get_backing_file(const char* disk) {
+	char* stdoutb = NULL;
+	char* stderrb = NULL;
+
+	// Get the backing file of the disk
+	int result = execute(&stdoutb, &stderrb, "qemu-img", "info", "--output", "json", disk, NULL);
+
+	// Check if the command was successful
+	if (result != 0) {
+		// Remove the newline character from the stderr buffer
+		size_t length = strlen(stderrb);
+		for (size_t i = 0; i < length; i++)
+			if (stderrb[i] == '\n')
+				stderrb[i] = ' ';
+		log_msg(LOG_ERROR, "Failed to get the backing file of the disk %s (%s)", disk, stderrb);
+
+		free(stdoutb);
+		free(stderrb);
+
+		return NULL;
+	}
+
+	free(stderrb);
+
+	// Parse the JSON output
+	json_object* root = json_tokener_parse(stdoutb);
+	if (root == NULL) {
+		log_msg(LOG_ERROR, "Failed to parse the JSON output of the command.");
+
+		free(stdoutb);
+
+		return NULL;
+	}
+
+	// Get the backing file
+	json_object* backing_file = NULL;
+	if (!json_object_object_get_ex(root, "backing-filename", &backing_file)) {
+		json_object_put(root);
+		free(stdoutb);
+
+		return NULL;
+	}
+
+	// Get the backing file as a string0
+	char* backing_file_str = strdup(json_object_get_string(backing_file));
+	if (backing_file_str == NULL) {
+		log_msg(LOG_ERROR, "Failed to get the backing file of the disk %s.", disk);
+
+		json_object_put(root);
+		free(stdoutb);
+
+		return NULL;
+	}
+
+	return backing_file_str;
+}

src/disk.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/// @brief Creates an empty disk.
+/// @param disk The path to the disk to create. Warning: the disk must not exist, otherwise it will be overwritten.
+/// @param size The size of the disk to create in bytes.
+/// @return true if the disk is created, otherwise false.
+bool create_empty_disk(const char* disk, uint64_t size);
+
+/// @brief Creates a backed disk.
+/// @param disk The path to the disk to create. Warning: the disk must not exist, otherwise it will be overwritten.
+/// @param backing The path to the backing file, which exists.
+/// @return true if the disk is created, otherwise false.
+bool create_backed_disk(const char* disk, const char* backing);
+
+/// @brief Packs the disk to reduce its size.
+/// @param disk The path to the disk to pack, which exists.
+/// @return true if the disk is packed, otherwise false.
+bool pack_disk(const char* disk);
+
+/// @brief Gets the backing file of a disk.
+/// @param disk The path to the disk, which exists.
+/// @return The backing file of the disk. The caller is responsible for freeing the returned string. This function can return NULL.
+char* get_backing_file(const char* disk);

src/entry.c

@@ -0,0 +1,70 @@
+#include "entry.h"
+
+#include "sandbox.h"
+#include "utils.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+char* get_entries_path(void) {
+	return format("%s/%s", MASTER_DIRECTORY, ENTRIES_DIRECTORY);
+}
+
+bool is_valid_entry_name(const char* name) {
+	if (name == NULL)
+		return false;
+
+	// Check that the name is not empty
+	size_t length = strlen(name);
+	if (length == 0)
+		return false;
+
+	// Check that the name does not contain /
+	for (size_t i = 0; i < length; i++)
+		if (name[i] == '/')
+			return false;
+
+	// Check that the name is not . or ..
+	if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0)
+		return false;
+
+	return true;
+}
+
+char* get_entry_path(const char* entry) {
+	char* entries_path = get_entries_path();
+	if (entries_path == NULL)
+		return NULL;
+
+	// Combine the entries path with the entry name
+	char* entry_path = format("%s/%s", entries_path, entry);
+
+	// Free the entries path
+	free(entries_path);
+
+	return entry_path;
+}
+
+bool entry_exists(const char* entry) {
+	char* entry_path = get_entry_path(entry);
+	if (entry_path == NULL)
+		return false;
+
+	// Check if the entry path exists
+	struct stat statbuf;
+	int result = stat(entry_path, &statbuf);
+
+	// Free the entry path
+	free(entry_path);
+
+	if (result != 0)
+		return false;
+
+	if (!S_ISDIR(statbuf.st_mode))
+		return false;
+
+	return true;
+}

src/entry.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+/// @brief Returns the directory path where the entries are stored.
+/// @return The directory path where the entries are stored. The caller is responsible for freeing the returned string. This function can return NULL.
+char* get_entries_path(void);
+
+/// @brief Checks if the specified entry name is valid.
+/// @param name The entry name to check.
+/// @return true if the entry name is valid, otherwise false.
+bool is_valid_entry_name(const char* name);
+
+/// @brief Returns the path to the specified entry.
+/// @param entry The valid entry name.
+/// @return The path to the specified entry. The caller is responsible for freeing the returned string. This function can return NULL.
+char* get_entry_path(const char* entry);
+
+/// @brief Checks if the specified entry exists.
+/// @param entry The valid entry name.
+/// @return true if the entry exists, otherwise false.
+bool entry_exists(const char* entry);
+
+/// @brief Lists the entries.
+/// @return The list of entries. The caller is responsible for freeing the returned array and strings. This function can return NULL.
+char** list_entries(void);

src/sandbox.c

@@ -0,0 +1,16 @@
+#include "sandbox.h"
+
+#include "utils.h"
+
+#include "backing.h"
+#include "entry.h"
+#include "disk.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <libgen.h>
+
+int main(int argc, char* argv[]) {
+	char** backings = list_backings();
+}

src/sandbox.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#define MASTER_DIRECTORY "/var/lib/sandbox"
+
+#define BACKINGS_DIRECTORY "backings"
+#define ENTRIES_DIRECTORY "entries"
+
+int main(int argc, char* argv[]);

src/utils.c

@@ -0,0 +1,271 @@
+#include "utils.h"
+
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+
+char* format(const char* fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+
+	// Calculate the length of the formatted string
+	size_t length = vsnprintf(NULL, 0, fmt, args) + 1;
+
+	va_end(args);
+
+	if (length <= 0)
+		return NULL;
+
+	// Allocate a buffer for the formatted string
+	char* buffer = calloc(length, sizeof(char));
+	if (buffer == NULL) {
+		log_msg(LOG_ERROR, "Failed to allocate memory for the formatted string.");
+		return NULL;
+	}
+
+	va_start(args, fmt);
+
+	// Format the string
+	vsnprintf(buffer, length, fmt, args);
+
+	va_end(args);
+
+	return buffer;
+}
+
+void log_msg(LogLevel level, const char* fmt, ...) {
+	va_list args;
+	va_start(args, fmt);
+
+	const char* color;
+	const char* level_str;
+
+	// Set the color and level string based on the log level
+	switch (level) {
+	case LOG_DEBUG:
+		color = "\033[0;90m";
+		level_str = "DEBUG";
+		break;
+	case LOG_INFO:
+		color = "\033[0;34m";
+		level_str = "INFO";
+		break;
+	case LOG_WARN:
+		color = "\033[0;33m";
+		level_str = "WARN";
+		break;
+	case LOG_ERROR:
+		color = "\033[0;31m";
+		level_str = "ERROR";
+		break;
+	default:
+		color = "";
+		level_str = "UNKNOWN";
+		break;
+	}
+
+	// Get the current time
+	time_t t = time(NULL);
+	struct tm* tm_info = localtime(&t);
+
+	// Print the label
+	fprintf(stderr, "%s[%02d/%02d/%02d %02d:%02d:%02d - %s]\033[m ", color, tm_info->tm_mday, tm_info->tm_mon + 1, (tm_info->tm_year + 1900) % 100, tm_info->tm_hour, tm_info->tm_min, tm_info->tm_sec, level_str);
+
+	// Print the message
+	vfprintf(stderr, fmt, args);
+
+	// Print a newline
+	fprintf(stderr, "\n");
+
+	// Flush the output
+	fflush(stderr);
+
+	va_end(args);
+}
+
+int execute(char** stdout_buffer, char** stderr_buffer, const char* file, ...) {
+	// Count the number of arguments
+	int argc = 1; // Include space for the file name
+	va_list args;
+	va_start(args, file);
+	while (va_arg(args, char*) != NULL)
+		argc++;
+	va_end(args);
+
+	// Allocate an array for the arguments
+	char** argv = calloc(argc + 1, sizeof(char*)); // Include space for the NULL terminator
+	if (argv == NULL) {
+		log_msg(LOG_ERROR, "Failed to allocate memory for the argument array.");
+		return -1;
+	}
+
+	// Fill the argument array
+	va_start(args, file);
+	argv[0] = strdup(file);
+	for (int i = 1; i < argc; i++)
+		argv[i] = strdup(va_arg(args, char*));
+	argv[argc] = NULL;
+	va_end(args);
+
+	// Create the stdout pipe for the child process
+	int stdout_pipe[2];
+	if (pipe(stdout_pipe) == -1) {
+		log_msg(LOG_ERROR, "Failed to create pipe for stdout.");
+
+		for (int i = 0; i < argc; i++)
+			free(argv[i]);
+		free(argv);
+
+		return -1;
+	}
+
+	// Create the stderr pipe for the child process
+	int stderr_pipe[2];
+	if (pipe(stderr_pipe) == -1) {
+		log_msg(LOG_ERROR, "Failed to create pipe for stderr.");
+
+		close(stdout_pipe[0]);
+		close(stdout_pipe[1]);
+
+		for (int i = 0; i < argc; i++)
+			free(argv[i]);
+		free(argv);
+
+		return -1;
+	}
+
+	// Fork the child process
+	pid_t pid = fork();
+
+	if (pid == -1) {
+		log_msg(LOG_ERROR, "Failed to fork child process.");
+
+		close(stdout_pipe[0]);
+		close(stdout_pipe[1]);
+		close(stderr_pipe[0]);
+		close(stderr_pipe[1]);
+
+		for (int i = 0; i < argc; i++)
+			free(argv[i]);
+		free(argv);
+
+		return -1;
+	}
+
+	if (pid == 0) {
+		// Redirect stdout and stderr to the pipes
+		dup2(stdout_pipe[1], STDOUT_FILENO);
+		dup2(stderr_pipe[1], STDERR_FILENO);
+
+		// Close the pipe file descriptors
+		close(stdout_pipe[0]);
+		close(stdout_pipe[1]);
+		close(stderr_pipe[0]);
+		close(stderr_pipe[1]);
+
+		// Execute the command
+		execvp(file, argv);
+
+		// If execvp fails, log an error
+		log_msg(LOG_ERROR, "Failed to execute command '%s'.", file);
+
+		// Free the argument array
+		for (int i = 0; i < argc; i++)
+			free(argv[i]);
+		free(argv);
+
+		exit(1);
+	}
+
+	// Close the write end of the pipes
+	close(stdout_pipe[1]);
+	close(stderr_pipe[1]);
+
+	// Wait for the child process to finish
+	int status;
+	waitpid(pid, &status, 0);
+
+	// Read the stdout buffer
+	char buffer[4096];
+	ssize_t bytes_read;
+
+	if (stdout_buffer != NULL) {
+		size_t stdout_length = 0;
+		*stdout_buffer = NULL;
+
+		// Read the stdout buffer
+		while ((bytes_read = read(stdout_pipe[0], buffer, sizeof(buffer))) > 0) {
+			char* new_stdout_buffer = realloc(*stdout_buffer, stdout_length + bytes_read + 1); // Include space for the null terminator
+			if (new_stdout_buffer == NULL) {
+				log_msg(LOG_ERROR, "Failed to allocate memory for the stdout buffer.");
+
+				free(*stdout_buffer);
+
+				close(stdout_pipe[0]);
+				close(stderr_pipe[0]);
+
+				for (int i = 0; i < argc; i++)
+					free(argv[i]);
+				free(argv);
+
+				return -1;
+			}
+			*stdout_buffer = new_stdout_buffer;
+
+			memcpy(*stdout_buffer + stdout_length, buffer, bytes_read);
+			stdout_length += bytes_read;
+			(*stdout_buffer)[stdout_length] = '\0';
+		}
+	}
+
+	// Close the read end of the stdout pipe
+	close(stdout_pipe[0]);
+
+	// Read the stderr buffer
+	if (stderr_buffer != NULL) {
+		size_t stderr_length = 0;
+		*stderr_buffer = NULL;
+
+		// Read the stderr buffer
+		while ((bytes_read = read(stderr_pipe[0], buffer, sizeof(buffer))) > 0) {
+			char* new_stderr_buffer = realloc(*stderr_buffer, stderr_length + bytes_read + 1); // Include space for the null terminator
+			if (new_stderr_buffer == NULL) {
+				log_msg(LOG_ERROR, "Failed to allocate memory for the stderr buffer.");
+
+				free(*stdout_buffer);
+				free(*stderr_buffer);
+
+				close(stderr_pipe[0]);
+
+				for (int i = 0; i < argc; i++)
+					free(argv[i]);
+				free(argv);
+
+				return -1;
+			}
+			*stderr_buffer = new_stderr_buffer;
+
+			memcpy(*stderr_buffer + stderr_length, buffer, bytes_read);
+			stderr_length += bytes_read;
+			(*stderr_buffer)[stderr_length] = '\0';
+		}
+	}
+
+	// Close the read end of the stderr pipe
+	close(stderr_pipe[0]);
+
+	// Free the argument array
+	for (int i = 0; i < argc; i++)
+		free(argv[i]);
+	free(argv);
+
+	// Return the exit status
+	return WIFEXITED(status) ? WEXITSTATUS(status) : -1;
+}
+

src/utils.h

@@ -0,0 +1,34 @@
+#pragma once
+
+/// @brief The log levels.
+typedef enum {
+	LOG_DEBUG,
+	LOG_INFO,
+	LOG_WARN,
+	LOG_ERROR,
+} LogLevel;
+
+/// @brief Formats a string using the specified format and arguments.
+/// @param fmt The format string.
+/// @param ... The arguments to use when formatting the string.
+/// @return The formatted string. The caller is responsible for freeing the returned string. This function can return NULL.
+char* format(const char* fmt, ...);
+
+/// @brief Logs a formatted message to the console.
+/// @param level The log level.
+/// @param fmt The format string.
+/// @param ... The arguments to use when formatting the string.
+void log_msg(LogLevel level, const char* fmt, ...);
+
+/// @brief Executes a command and returns the exit code.
+/// @param stdout_buffer A pointer to a buffer that will receive the standard output of the command. The caller is responsible for freeing the buffer. This parameter can be NULL.
+/// @param stderr_buffer A pointer to a buffer that will receive the standard error of the command. The caller is responsible for freeing the buffer. This parameter can be NULL.
+/// @param file The path to the command to execute.
+/// @param ... The arguments to pass to the command, followed by a NULL pointer. No need to include the command name in the arguments.
+/// @return The exit code of the command.
+int execute(char** stdout_buffer, char** stderr_buffer, const char* file, ...);
+
+/// @brief Returns a list of the files in the specified directory.
+/// @param directory The directory to list.
+/// @return The list of files in the specified directory. The caller is responsible for freeing the returned array and strings. This function can return NULL.
+char** list_files(const char* directory);