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#include <camellia/flags.h>
#include <camellia/syscalls.h>
#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <user/lib/fs/misc.h>
static const char *shell = "/bin/shell";
static void cutspace(char *s) {
for (; *s; s++) {
if (isspace(*s)) {
*s = '\0';
break;
}
}
}
static bool accesscheck(const char *path) {
const char *prefix = "/Users/";
if (strlen(path) < strlen(prefix) || memcmp(path, prefix, strlen(prefix)))
return true; /* not an user dir - access allowed */
path += strlen(prefix);
/* skip username */
path = strchr(path, '/');
if (!path) return true;
path++;
/* inside an user dir */
const char *private = "private/";
return strlen(path) < strlen(private) || memcmp(path, private, strlen(private));
}
static void drv(const char *prefix) {
struct fs_wait_response res;
size_t prefixlen = strlen(prefix);
char buf[128];
while (!_syscall_fs_wait(buf, sizeof buf, &res)) {
switch (res.op) {
handle_t h;
case VFSOP_OPEN:
if (res.len == sizeof buf) {
_syscall_fs_respond(NULL, -1, 0);
break;
}
buf[res.len] = '\0';
if (res.len >= prefixlen && !memcmp(prefix, buf, prefixlen)) {
h = _syscall_open(buf, res.len, res.flags);
} else if (accesscheck(buf)) {
h = _syscall_open(buf, res.len, res.flags | OPEN_RO);
} else {
h = -EACCES;
}
_syscall_fs_respond(NULL, h, FSR_DELEGATE);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
}
static void trylogin(const char *user) {
if (strcmp(user, "root")) {
char buf[128];
snprintf(buf, sizeof buf, "/Users/%s/", user);
if (chdir(buf) < 0) {
printf("no such user: %s\n", user);
return;
}
MOUNT_AT("/") { drv(buf); }
}
execv(shell, NULL);
fprintf(stderr, "login: couldn't launch %s\n", shell);
exit(1);
}
int main(void) {
char user[64];
printf("\nCamellia\n");
for (;;) {
printf("login: ");
fgets(user, sizeof user, stdin);
if (ferror(stdin)) return -1;
cutspace(user);
if (user[0]) trylogin(user);
}
}
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