// Changes the permissions of the file
unsigned int fs_chmod(char * filename, int perms) {
int current_uid = current_ttyc()->uid;
int start_inode = current_ttyc()->pwd;
int namenode = fs_indir(filename, start_inode);
if (namenode) {
inode_read(namenode, &n);
if (n.uid == current_uid || current_uid == 0) {
n.i_file_acl = perms;
inode_write(namenode, &n);
} else {
return ERR_PERMS;
}
return 1;
} else {
return ERR_NO_EXIST;
}
}
// Returns the inode's permissions
unsigned int fs_getmod(char * filename) {
int start_inode = current_ttyc()->pwd;
int namenode = fs_indir(filename, start_inode);
if (namenode) {
inode_read(namenode, &n);
return n.i_file_acl & 0777;
} else {
return ERR_NO_EXIST;
}
}
// Changes the inode's owner
unsigned int fs_chown(char * filename, char * username) {
int new_uid = user_exists(username);
int current_uid = current_ttyc()->uid;
int start_inode = current_ttyc()->pwd;
int namenode = fs_indir(filename, start_inode);
if (namenode && new_uid != -1) {
inode_read(namenode, &n);
if (n.uid == current_uid || current_uid == 0) {
n.uid = new_uid;
inode_write(namenode, &n);
} else {
return ERR_PERMS;
}
return 1;
} else {
return ERR_NO_EXIST;
}
}
/* Opens a file descriptor and sets it's type, data and permissions*/
int fd_open_with_index (int fd, int type, void * data, int perms) {
if(files_allocd == 0) {
files_alloc();
}
if(!files[fd].used) {
files[fd].type = type;
files[fd].data = data;
files[fd].perms = perms;
switch(files[fd].type) {
case _FD_TTY:
//
break;
case _FD_FIFO:
files[fd].fifo_inode = (int) fs_open_fifo(data, current_ttyc()->pwd, perms); // Fifos are stored with their own id...
if(files[fd].fifo_inode > 0) {
files[fd].data = (void *) fifo_make(files[fd].fifo_inode);
}
break;
case _FD_FILE:
files[fd].data = (void *)fs_open_reg_file(data, current_ttyc()->pwd, perms); // Inodes are stoded with their inode number.
if(files[fd].data > 0 && fs_is_fifo((int)files[fd].data))
{
files[fd].fifo_inode = (int) files[fd].data;
files[fd].data = (void *) fifo_make(files[fd].fifo_inode);
files[fd].type = _FD_FIFO;
}
break;
default:
return -1;
}
}
// Errors...
if((int)files[fd].fifo_inode < 0 && type == _FD_FIFO) {
return (int)files[fd].fifo_inode;
}
if((int)files[fd].data < 0 && type == _FD_FILE) {
return (int)files[fd].data;
}
files[fd].used++;
return fd;
}
// Changes the directory
int fs_cd(char * name) {
int start_inode = current_ttyc()->pwd;
int namenode = fs_indir(name, start_inode);
if (namenode) {
inode_read(namenode, &n);
if(n.mode & EXT2_S_IFLNK) {
if (bitmap_read(bm_inodes, n.data_blocks[0] - 1))
current_ttyc()->pwd = n.data_blocks[0];
else {
return ERR_NO_EXIST;
}
} else {
current_ttyc()->pwd = namenode;
}
return 1;
} else {
return ERR_NO_EXIST;
}
}
// Gets info from the file
void fs_finfo(char * filename, int * data) {
int start_inode = current_ttyc()->pwd;
int namenode = fs_indir(filename, start_inode);
if(namenode)
{
inode_read(namenode, &n);
data[0] = namenode; // Inode
data[1] = n.blocks / 2; // Blocks
data[2] = n.blocks / 2 * 1024; // Bytes
data[3] = n.i_file_acl; // Permissions
data[4] = n.uid; // UID
data[5] = n._dir_inode; // Directory inode
}
}
// Opens a link filetype
unsigned int fs_open_link(char * name, char * target_name) {
unsigned int folder_inode = current_ttyc()->pwd;
int target_inode = fs_indir(target_name, folder_inode);
if(target_inode > 0)
{
int result = fs_open_file(name, folder_inode, O_NEW, EXT2_S_IFLNK);
if(result > 0) {
inode_read(result, &n);
n.data_blocks[0] = target_inode;
inode_write(result, &n);
return 1;
}
else {
return result;
}
} else {
return ERR_NO_EXIST;
}
}
// Tells the current location
char * fs_pwd() {
int j = 1023;
int i = 0;
for(; i < 1024; ++i) {
pwd_string[i] = 0;
}
int start_inode = current_ttyc()->pwd;
inode_read(start_inode, &n);
while(n._dir_inode != start_inode) {
int _old_dirnode = n._dir_inode;
char * name = fs_iname(start_inode, n._dir_inode);
int k = strlen(name) - 2;
for(; k >= 0; k--, j--) {
pwd_string[j] = name[k];
}
pwd_string[j] = '/';
j--;
start_inode = _old_dirnode;
inode_read(start_inode, &n);
}
if(j == 1023)
{
pwd_string[j] = '/';
} else {
j++;
}
for(i = 0; j < 1024; i++,j++)
{
pwd_string[i] = pwd_string[j];
pwd_string[j] = 0;
}
return pwd_string;
}
// Tells if the current user has permissions to make an action in the given inode
unsigned int fs_has_perms(inode * n, int for_what) {
if (!fs_done) {
// If the kernel's not ready then we can do anything.
// We're like, Chuck Norris, a superroot or Chuck Testa.
return 1;
}
int current_uid = current_ttyc()->uid;
int current_gid = user_gid(current_uid);
int file_gid = user_gid(n->uid);
int can = 0;
if(for_what == ACTION_READ)
{
if (n->uid == current_uid && (n->i_file_acl & 0400)) {
can = 1;
}
if (file_gid == current_gid && (n->i_file_acl & 0040)) {
can = 1;
}
if (n->i_file_acl & 0004) {
can = 1;
}
} else if(for_what == ACTION_WRITE)
{
if (n->uid == current_uid && (n->i_file_acl & 0200)) {
can = 1;
}
if (file_gid == current_gid && (n->i_file_acl & 0020)) {
can = 1;
}
if (n->i_file_acl & 0002) {
can = 1;
}
}
return can;
}
// Makes a new directory
unsigned int fs_mkdir(char * name, unsigned int parent_inode) {
unsigned int inode_id = 0;
if ((inode_id = fs_indir(name, parent_inode))) {
return 0;
}
inode_id = bitmap_first_valued(bm_inodes, FS_INODE_BITMAP_SIZE, 0) + 1;
if (!parent_inode) {
parent_inode = inode_id;
}
int log_block;
if (parent_inode != inode_id) {
inode_read(parent_inode, &n);
if(!fs_has_perms(&n, ACTION_WRITE)) {
return ERR_PERMS;
}
log_block = n.blocks / 2;
block_clear(&b);
dir_op_offset = 0;
log_block_read(&n, &log_block);
add_dir_entry(&n, EXT2_FT_DIR, inode_id, name, &log_block);
log_block_write(&n, &log_block);
inode_write(parent_inode, &n);
}
bitmap_write(bm_inodes, inode_id - 1, 1);
inode_clear(&n);
if(!fs_done)
{
n.uid = 0;
} else {
n.uid = current_ttyc()->uid;
}
n.mode = EXT2_S_IFDIR;
n.size = 0;
n.blocks = 0; // Beware! This represents the SECTORS!
log_block = n.blocks / 2;
block_clear(&b);
dir_op_offset = 0;
add_dir_entry(&n, EXT2_FT_DIR, inode_id, ".", &log_block);
add_dir_entry(&n, EXT2_FT_DIR, parent_inode, "..", &log_block);
log_block_write(&n, &log_block);
n.blocks = (log_block) * 2;
n.i_file_acl = 511;
n._dir_inode = parent_inode;
n._last_write_offset = dir_op_offset;
inode_write(inode_id, &n);
fs_bitmaps_write_all();
return inode_id;
}
// Opens a file
unsigned int fs_open_file(char * name, unsigned int folder_inode, int mode, int type) {
unsigned int inode_id = 0;
if(strcmp(name, "/") == 0 && strlen(name) == strlen("/")) {
return 1; // root
}
if(name[0] == 0)
{
inode_id = current_ttyc()->pwd;
} else {
inode_id = fs_indir(name, folder_inode);
}
if (inode_id) {
if (mode & O_CREAT) {
int _rm_res = fs_rm(inode_id, 0);
if(_rm_res < 0) {
return _rm_res;
}
} else if(mode & O_NEW) {
inode_read(inode_id, &n);
if(n.mode == EXT2_S_IFLNK) {
return n.data_blocks[0];
}
return inode_id;
}
else {
inode_read(inode_id, &n);
int can = 1;
if((mode & O_RD) && !fs_has_perms(&n, ACTION_READ)) {
can = 0;
}
if((mode & O_WR) && !fs_has_perms(&n, ACTION_WRITE)) {
can = 0;
}
if(can || !fs_done) {
if(n.mode == EXT2_S_IFLNK) {
return n.data_blocks[0];
}
return inode_id;
} else {
return ERR_PERMS;
}
}
} else if (!(mode & (O_NEW | O_CREAT))) {
return ERR_NO_EXIST;
}
inode_id = bitmap_first_valued(bm_inodes, FS_INODE_BITMAP_SIZE, 0) + 1;
if (!folder_inode) {
folder_inode = inode_id;
}
int log_block;
if (folder_inode != inode_id) {
inode_read(folder_inode, &n);
if(!fs_has_perms(&n, ACTION_WRITE)) {
return ERR_PERMS;
}
log_block = n.blocks / 2;
block_clear(&b);
dir_op_offset = 0;
log_block_read(&n, &log_block);
add_dir_entry(&n, EXT2_FT_DIR, inode_id, name, &log_block);
log_block_write(&n, &log_block);
inode_write(folder_inode, &n);
}
bitmap_write(bm_inodes, inode_id - 1, 1);
inode_clear(&n);
if(!fs_done)
{
n.uid = 0;
} else {
n.uid = current_ttyc()->uid;
}
n.mode = type;
n.size = 0;
n.blocks = 0; // Beware! This represents the SECTORS!
n._last_write_offset = 0;
n.i_file_acl = 511;
n._dir_inode = folder_inode;
inode_write(inode_id, &n);
inode_clear(&n);
if(n.mode == EXT2_S_IFLNK) {
return n.data_blocks[0];
}
return inode_id;
}
// INT 80h Handler, kernel entry.
void int_80() {
if(krn) {
return;
}
krn++;
int systemCall = kernel_buffer[0];
int fd = kernel_buffer[1];
int buffer = kernel_buffer[2];
int count = kernel_buffer[3];
int i, j;
Process * current;
Process * p;
int inode;
int _fd;
// Yeah, wanna know why we don't access an array directly? ... Because of big bugs we might have.
switch(systemCall) {
case READY:
kernel_buffer[KERNEL_RETURN] = kernel_ready();
break;
case WRITE:
current = getp();
kernel_buffer[KERNEL_RETURN] = fd_write(current->file_descriptors[fd],(char *)buffer,count);
break;
case READ:
current = getp();
kernel_buffer[KERNEL_RETURN] = fd_read(current->file_descriptors[fd],(char *)buffer,count);
break;
case MKFIFO:
_fd = process_getfreefd();
fd = fd_open(_FD_FIFO, (void *)kernel_buffer[1],kernel_buffer[2]);
if(_fd != -1 && fd != -1) {
getp()->file_descriptors[_fd] = fd;
kernel_buffer[KERNEL_RETURN] = _fd;
}
else {
kernel_buffer[KERNEL_RETURN] = -1;
}
break;
case OPEN:
_fd = process_getfreefd();
fd = fd_open(_FD_FILE, (void *) kernel_buffer[1], kernel_buffer[2]);
if(_fd != -1 && fd >= 0)
{
getp()->file_descriptors[_fd] = fd;
kernel_buffer[KERNEL_RETURN] = _fd;
}
else {
kernel_buffer[KERNEL_RETURN] = fd;
}
break;
case CLOSE:
kernel_buffer[KERNEL_RETURN] = fd_close(getp()->file_descriptors[fd]);
break;
case PCREATE:
kernel_buffer[KERNEL_RETURN] = sched_pcreate(kernel_buffer[1],kernel_buffer[2],kernel_buffer[3]);
break;
case PRUN:
kernel_buffer[KERNEL_RETURN] = sched_prun(kernel_buffer[1]);
break;
case PDUP2:
kernel_buffer[KERNEL_RETURN] = sched_pdup2(kernel_buffer[1],kernel_buffer[2],kernel_buffer[3]);
break;
case GETPID:
kernel_buffer[KERNEL_RETURN] = sched_getpid();
break;
case WAITPID:
kernel_buffer[KERNEL_RETURN] = sched_waitpid(kernel_buffer[1]);
break;
case PTICKS:
kernel_buffer[KERNEL_RETURN] = (int) storage_index();
break;
case PNAME:
p = process_getbypid(kernel_buffer[1]);
if(p == NULL)
{
kernel_buffer[KERNEL_RETURN] = (int) NULL;
} else {
kernel_buffer[KERNEL_RETURN] = (int) p->name;
}
break;
case PSTATUS:
p = process_getbypid(kernel_buffer[1]);
if(p == NULL)
{
kernel_buffer[KERNEL_RETURN] = (int) -1;
} else {
kernel_buffer[KERNEL_RETURN] = (int) p->state;
}
break;
case PPRIORITY:
p = process_getbypid(kernel_buffer[1]);
if(p == NULL)
{
kernel_buffer[KERNEL_RETURN] = (int) -1;
} else {
kernel_buffer[KERNEL_RETURN] = (int) p->priority;
}
break;
case PGID:
p = process_getbypid(kernel_buffer[1]);
if(p == NULL)
{
kernel_buffer[KERNEL_RETURN] = (int) -1;
} else {
kernel_buffer[KERNEL_RETURN] = (int) p->gid;
}
break;
case PGETPID_AT:
p = process_getbypindex(kernel_buffer[1]);
if (p->state != -1) {
kernel_buffer[KERNEL_RETURN] = (int) p->pid;
} else {
kernel_buffer[KERNEL_RETURN] = -1;
}
break;
case KILL:
kernel_buffer[KERNEL_RETURN - 1] = kernel_buffer[1];
kernel_buffer[KERNEL_RETURN - 2] = kernel_buffer[2];
break;
case PSETP:
p = process_getbypid(kernel_buffer[1]);
if(p == NULL) {
kernel_buffer[KERNEL_RETURN] = (int) -1;
} else {
if(kernel_buffer[2] <= 4 && kernel_buffer[2] >= 0) {
p->priority = kernel_buffer[2];
}
kernel_buffer[KERNEL_RETURN] = (int) p->gid;
}
break;
case SETSCHED:
sched_set_mode(kernel_buffer[1]);
break;
case PWD:
kernel_buffer[KERNEL_RETURN] = (int) fs_pwd();
break;
case CD:
kernel_buffer[KERNEL_RETURN] = (int) fs_cd(kernel_buffer[1]);
break;
case FINFO:
fs_finfo(kernel_buffer[1], kernel_buffer[2]);
break;
case MOUNT:
fs_init();
break;
case MKDIR:
kernel_buffer[KERNEL_RETURN] = (int) fs_mkdir(kernel_buffer[1],current_ttyc()->pwd);
break;
case RM:
inode = fs_indir(kernel_buffer[1],current_ttyc()->pwd);
if (inode) {
kernel_buffer[KERNEL_RETURN] = (int) fs_rm(inode,0);
} else {
kernel_buffer[KERNEL_RETURN] = ERR_NO_EXIST;
}
break;
case GETUID:
if(kernel_buffer[1] == 0)
{
kernel_buffer[KERNEL_RETURN] = (int) current_ttyc()->uid;
} else {
kernel_buffer[KERNEL_RETURN] = (int) user_exists(kernel_buffer[1]);
}
break;
case GETGID:
if(kernel_buffer[1] == 0)
{
kernel_buffer[KERNEL_RETURN] = (int) user_gid(current_ttyc()->uid);
} else {
kernel_buffer[KERNEL_RETURN] = (int) user_gid(kernel_buffer[1]);
}
break;
case MAKEUSER:
kernel_buffer[KERNEL_RETURN] = user_create(kernel_buffer[1],
kernel_buffer[2], user_gid(current_ttyc()->uid));
break;
case SETGID:
kernel_buffer[KERNEL_RETURN] = user_setgid(kernel_buffer[1],
kernel_buffer[2]);
break;
case UDELETE:
kernel_buffer[KERNEL_RETURN] = user_delete(kernel_buffer[1]);
break;
case UEXISTS:
kernel_buffer[KERNEL_RETURN] = user_exists(kernel_buffer[1]);
break;
case ULOGIN:
kernel_buffer[KERNEL_RETURN] = user_login(kernel_buffer[1],
kernel_buffer[2]);
break;
case ULOGOUT:
kernel_buffer[KERNEL_RETURN] = user_logout();
break;
case CHOWN:
kernel_buffer[KERNEL_RETURN] = fs_chown(kernel_buffer[1],
kernel_buffer[2]);
break;
case CHMOD:
kernel_buffer[KERNEL_RETURN] = fs_chmod(kernel_buffer[1],
kernel_buffer[2]);
break;
case GETOWN:
kernel_buffer[KERNEL_RETURN] = fs_getown(kernel_buffer[1]);
break;
case GETMOD:
kernel_buffer[KERNEL_RETURN] = fs_getmod(kernel_buffer[1]);
break;
case CP:
kernel_buffer[KERNEL_RETURN] = fs_cp(kernel_buffer[1], kernel_buffer[2], current_ttyc()->pwd, current_ttyc()->pwd);
break;
case MV:
kernel_buffer[KERNEL_RETURN] = fs_mv(kernel_buffer[1], kernel_buffer[2], current_ttyc()->pwd);
break;
case LINK:
kernel_buffer[KERNEL_RETURN] = fs_open_link(kernel_buffer[1], kernel_buffer[2], current_ttyc()->pwd);
break;
case FSSTAT:
kernel_buffer[KERNEL_RETURN] = fs_stat(kernel_buffer[1]);
break;
case SLEEP:
kernel_buffer[KERNEL_RETURN] = scheduler_sleep(kernel_buffer[1]);
break;
default:
break;
}
krn--;
}
