bsd-user: Implement getgroups(2) and setgroups(2) system calls.

Signed-off-by: Stacey Son <sson@FreeBSD.org>
Signed-off-by: Karim Taha <kariem.taha2.7@gmail.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20230925182425.3163-12-kariem.taha2.7@gmail.com>

bsd-user/bsd-proc.h

@@ -41,4 +41,48 @@ static inline abi_long do_bsd_exit(void *cpu_env, abi_long arg1)
     return 0;
 }
 
+/* getgroups(2) */
+static inline abi_long do_bsd_getgroups(abi_long gidsetsize, abi_long arg2)
+{
+    abi_long ret;
+    uint32_t *target_grouplist;
+    g_autofree gid_t *grouplist;
+    int i;
+
+    grouplist = g_try_new(gid_t, gidsetsize);
+    ret = get_errno(getgroups(gidsetsize, grouplist));
+    if (gidsetsize != 0) {
+        if (!is_error(ret)) {
+            target_grouplist = lock_user(VERIFY_WRITE, arg2, gidsetsize * 2, 0);
+            if (!target_grouplist) {
+                return -TARGET_EFAULT;
+            }
+            for (i = 0; i < ret; i++) {
+                target_grouplist[i] = tswap32(grouplist[i]);
+            }
+            unlock_user(target_grouplist, arg2, gidsetsize * 2);
+        }
+    }
+    return ret;
+}
+
+/* setgroups(2) */
+static inline abi_long do_bsd_setgroups(abi_long gidsetsize, abi_long arg2)
+{
+    uint32_t *target_grouplist;
+    g_autofree gid_t *grouplist;
+    int i;
+
+    grouplist = g_try_new(gid_t, gidsetsize);
+    target_grouplist = lock_user(VERIFY_READ, arg2, gidsetsize * 2, 1);
+    if (!target_grouplist) {
+        return -TARGET_EFAULT;
+    }
+    for (i = 0; i < gidsetsize; i++) {
+        grouplist[i] = tswap32(target_grouplist[i]);
+    }
+    unlock_user(target_grouplist, arg2, 0);
+    return get_errno(setgroups(gidsetsize, grouplist));
+}
+
 #endif /* !BSD_PROC_H_ */

bsd-user/freebsd/os-syscall.c

@@ -223,6 +223,15 @@ static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
         ret = do_bsd_exit(cpu_env, arg1);
         break;
 
+    case TARGET_FREEBSD_NR_getgroups: /* getgroups(2) */
+        ret = do_bsd_getgroups(arg1, arg2);
+        break;
+
+    case TARGET_FREEBSD_NR_setgroups: /* setgroups(2) */
+        ret = do_bsd_setgroups(arg1, arg2);
+        break;
+
+
         /*
          * File system calls.
          */