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#include <camellia/flags.h>
#include <camellia/syscalls.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <user/lib/compat.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;
}
}
}
bool segcmp(const char *path, int idx, const char *s2) {
if (idx < 0) return false;
while (idx > 0) {
if (*path == '\0') return false;
if (*path == '/') idx--;
path++;
}
/* path is at the start of the selected segment */
while (*s2 && *path++ == *s2++);
return (*path == '\0' || *path == '/') && *s2 == '\0';
}
static void drv(const char *user) {
struct ufs_request res;
char *buf = malloc(PATH_MAX);
while (!c0_fs_wait(buf, PATH_MAX, &res)) {
switch (res.op) {
handle_t h;
case VFSOP_OPEN:
/* null terminate */
if (res.len == PATH_MAX) {
c0_fs_respond(NULL, -1, 0);
break;
}
buf[res.len] = '\0';
// TODO use forward_open
if (segcmp(buf, 1, "Users") && segcmp(buf, 2, user)) {
// allow full rw access to /Users/$user/**
h = _syscall_open(buf, res.len, res.flags);
} else if (segcmp(buf, 1, "Users") && segcmp(buf, 3, "private")) {
// disallow access to /Users/*/private/**
h = -EACCES;
} else {
// allow ro access to everything else
h = _syscall_open(buf, res.len, res.flags | OPEN_RO);
}
c0_fs_respond(NULL, h, FSR_DELEGATE);
break;
default:
c0_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(user); }
}
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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