1 files changed, 119 insertions, 0 deletions
diff --git a/lib/libposix1e/acl_calc_mask.c b/lib/libposix1e/acl_calc_mask.c
new file mode 100644
index 0000000..ebacb02
--- /dev/null
+++ b/lib/libposix1e/acl_calc_mask.c
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2001 Chris D. Faulhaber
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR THE VOICES IN HIS HEAD BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/types.h>
+#include <sys/acl.h>
+
+#include <errno.h>
+
+/*
+ * acl_calc_mask() calculates and set the permissions associated
+ * with the ACL_MASK ACL entry.  If the ACL already contains an
+ * ACL_MASK entry, its permissions shall be overwritten; if not,
+ * one shall be added.
+ */
+int
+acl_calc_mask(acl_t *acl_p)
+{
+	acl_t acl_new;
+	int group_obj, i, mask_mode, mask_num, other_obj, user_obj;
+
+	/* check args */
+	if (!acl_p || !*acl_p || ((*acl_p)->acl_cnt < 3) ||
+	    ((*acl_p)->acl_cnt > ACL_MAX_ENTRIES)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	acl_new = acl_dup(*acl_p);
+	if (!acl_new)
+		return -1;
+
+	user_obj = group_obj = other_obj = mask_mode = 0;
+	mask_num = -1;
+
+	/* gather permissions and find a mask entry */
+	for (i = 0; i < acl_new->acl_cnt; i++) {
+		switch(acl_new->acl_entry[i].ae_tag) {
+		case ACL_USER_OBJ:
+			user_obj++;
+			break;
+		case ACL_OTHER:
+			other_obj++;
+			break;
+		case ACL_GROUP_OBJ:
+			group_obj++;
+			/* FALLTHROUGH */
+		case ACL_GROUP:
+		case ACL_USER:
+			mask_mode |=
+			    acl_new->acl_entry[i].ae_perm & ACL_PERM_BITS;
+			break;
+		case ACL_MASK:
+			mask_num = i;
+			break;
+		default:
+			errno = EINVAL;
+			acl_free(acl_new);
+			return -1;
+			/* NOTREACHED */
+		}
+	}
+	if ((user_obj != 1) || (group_obj != 1) || (other_obj != 1)) {
+		errno = EINVAL;
+		acl_free(acl_new);
+		return -1;
+	}
+	/* if a mask entry already exists, overwrite the perms */
+	if (mask_num != -1) {
+		acl_new->acl_entry[mask_num].ae_perm = mask_mode;
+	} else {
+		/* if no mask exists, check acl_cnt... */
+		if (acl_new->acl_cnt == ACL_MAX_ENTRIES) {
+			errno = EINVAL;
+			acl_free(acl_new);
+			return -1;
+		}
+		/* ...and add the mask entry */
+		acl_new->acl_entry[acl_new->acl_cnt].ae_tag  = ACL_MASK;
+		acl_new->acl_entry[acl_new->acl_cnt].ae_id   = 0;
+		acl_new->acl_entry[acl_new->acl_cnt].ae_perm = mask_mode;
+		acl_new->acl_cnt++;
+	}
+
+	if (acl_valid(acl_new) == -1) {
+		errno = EINVAL;
+		acl_free(acl_new);
+		return -1;
+	}
+
+	**acl_p = *acl_new;
+	acl_free(acl_new);
+
+	return 0;
+}