Move POSIX.1e-specific utility routines from kern_acl.c to

subr_acl_posix1e.c, leaving kern_acl.c containing only ACL system
calls and utility routines common across ACL types.

Add subr_acl_posix1e.c to the build.

Obtained from:	TrustedBSD Project

1 files changed, 4 insertions, 584 deletions

diff --git a/sys/kern/vfs_acl.c b/sys/kern/vfs_acl.c
index f346f61..64ffe5c 100644
--- a/sys/kern/vfs_acl.c
+++ b/sys/kern/vfs_acl.c
@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 1999-2003 Robert N. M. Watson
+ * Copyright (c) 1999-2006 Robert N. M. Watson
  * All rights reserved.
  *
  * This software was developed by Robert Watson for the TrustedBSD Project.
@@ -27,7 +27,9 @@
  */
 /*
  * Developed by the TrustedBSD Project.
- * Support for POSIX.1e access control lists.
+ *
+ * ACL system calls and other functions common across different ACL types.
+ * Type-specific routines go into subr_acl_<type>.c.
  */
 
 #include <sys/cdefs.h>
@@ -50,8 +52,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/filedesc.h>
 #include <sys/proc.h>
 #include <sys/sysent.h>
-#include <sys/errno.h>
-#include <sys/stat.h>
 #include <sys/acl.h>
 
 #include <vm/uma.h>
@@ -65,586 +65,6 @@ static int	vacl_aclcheck(struct thread *td, struct vnode *vp,
 		    acl_type_t type, struct acl *aclp);
 
 /*
- * Implement a version of vaccess() that understands POSIX.1e ACL semantics.
- * Return 0 on success, else an errno value.  Should be merged into
- * vaccess() eventually.
- */
-int
-vaccess_acl_posix1e(enum vtype type, uid_t file_uid, gid_t file_gid,
-    struct acl *acl, mode_t acc_mode, struct ucred *cred, int *privused)
-{
-	struct acl_entry *acl_other, *acl_mask;
-	mode_t dac_granted;
-	mode_t cap_granted;
-	mode_t acl_mask_granted;
-	int group_matched, i;
-
-	/*
-	 * Look for a normal, non-privileged way to access the file/directory
-	 * as requested.  If it exists, go with that.  Otherwise, attempt
-	 * to use privileges granted via cap_granted.  In some cases,
-	 * which privileges to use may be ambiguous due to "best match",
-	 * in which case fall back on first match for the time being.
-	 */
-	if (privused != NULL)
-		*privused = 0;
-
-	/*
-	 * Determine privileges now, but don't apply until we've found
-	 * a DAC entry that matches but has failed to allow access.
-	 */
-#ifndef CAPABILITIES
-	if (suser_cred(cred, SUSER_ALLOWJAIL) == 0)
-		cap_granted = VALLPERM;
-	else
-		cap_granted = 0;
-#else
-	cap_granted = 0;
-
-	if (type == VDIR) {
-		if ((acc_mode & VEXEC) && !cap_check(cred, NULL,
-		     CAP_DAC_READ_SEARCH, SUSER_ALLOWJAIL))
-			cap_granted |= VEXEC;
-	} else {
-		if ((acc_mode & VEXEC) && !cap_check(cred, NULL,
-		    CAP_DAC_EXECUTE, SUSER_ALLOWJAIL))
-			cap_granted |= VEXEC;
-	}
-
-	if ((acc_mode & VREAD) && !cap_check(cred, NULL, CAP_DAC_READ_SEARCH,
-	    SUSER_ALLOWJAIL))
-		cap_granted |= VREAD;
-
-	if (((acc_mode & VWRITE) || (acc_mode & VAPPEND)) &&
-	    !cap_check(cred, NULL, CAP_DAC_WRITE, SUSER_ALLOWJAIL))
-		cap_granted |= (VWRITE | VAPPEND);
-
-	if ((acc_mode & VADMIN) && !cap_check(cred, NULL, CAP_FOWNER,
-	    SUSER_ALLOWJAIL))
-		cap_granted |= VADMIN;
-#endif /* CAPABILITIES */
-
-	/*
-	 * The owner matches if the effective uid associated with the
-	 * credential matches that of the ACL_USER_OBJ entry.  While we're
-	 * doing the first scan, also cache the location of the ACL_MASK
-	 * and ACL_OTHER entries, preventing some future iterations.
-	 */
-	acl_mask = acl_other = NULL;
-	for (i = 0; i < acl->acl_cnt; i++) {
-		switch (acl->acl_entry[i].ae_tag) {
-		case ACL_USER_OBJ:
-			if (file_uid != cred->cr_uid)
-				break;
-			dac_granted = 0;
-			dac_granted |= VADMIN;
-			if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
-				dac_granted |= VEXEC;
-			if (acl->acl_entry[i].ae_perm & ACL_READ)
-				dac_granted |= VREAD;
-			if (acl->acl_entry[i].ae_perm & ACL_WRITE)
-				dac_granted |= (VWRITE | VAPPEND);
-			if ((acc_mode & dac_granted) == acc_mode)
-				return (0);
-			if ((acc_mode & (dac_granted | cap_granted)) ==
-			    acc_mode) {
-				if (privused != NULL)
-					*privused = 1;
-				return (0);
-			}
-			goto error;
-
-		case ACL_MASK:
-			acl_mask = &acl->acl_entry[i];
-			break;
-
-		case ACL_OTHER:
-			acl_other = &acl->acl_entry[i];
-			break;
-
-		default:
-			break;
-		}
-	}
-
-	/*
-	 * An ACL_OTHER entry should always exist in a valid access
-	 * ACL.  If it doesn't, then generate a serious failure.  For now,
-	 * this means a debugging message and EPERM, but in the future
-	 * should probably be a panic.
-	 */
-	if (acl_other == NULL) {
-		/*
-		 * XXX This should never happen
-		 */
-		printf("vaccess_acl_posix1e: ACL_OTHER missing\n");
-		return (EPERM);
-	}
-
-	/*
-	 * Checks against ACL_USER, ACL_GROUP_OBJ, and ACL_GROUP fields
-	 * are masked by an ACL_MASK entry, if any.  As such, first identify
-	 * the ACL_MASK field, then iterate through identifying potential
-	 * user matches, then group matches.  If there is no ACL_MASK,
-	 * assume that the mask allows all requests to succeed.
-	 */
-	if (acl_mask != NULL) {
-		acl_mask_granted = 0;
-		if (acl_mask->ae_perm & ACL_EXECUTE)
-			acl_mask_granted |= VEXEC;
-		if (acl_mask->ae_perm & ACL_READ)
-			acl_mask_granted |= VREAD;
-		if (acl_mask->ae_perm & ACL_WRITE)
-			acl_mask_granted |= (VWRITE | VAPPEND);
-	} else
-		acl_mask_granted = VEXEC | VREAD | VWRITE | VAPPEND;
-
-	/*
-	 * Iterate through user ACL entries.  Do checks twice, first
-	 * without privilege, and then if a match is found but failed,
-	 * a second time with privilege.
-	 */
-
-	/*
-	 * Check ACL_USER ACL entries.
-	 */
-	for (i = 0; i < acl->acl_cnt; i++) {
-		switch (acl->acl_entry[i].ae_tag) {
-		case ACL_USER:
-			if (acl->acl_entry[i].ae_id != cred->cr_uid)
-				break;
-			dac_granted = 0;
-			if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
-				dac_granted |= VEXEC;
-			if (acl->acl_entry[i].ae_perm & ACL_READ)
-				dac_granted |= VREAD;
-			if (acl->acl_entry[i].ae_perm & ACL_WRITE)
-				dac_granted |= (VWRITE | VAPPEND);
-			dac_granted &= acl_mask_granted;
-			if ((acc_mode & dac_granted) == acc_mode)
-				return (0);
-			if ((acc_mode & (dac_granted | cap_granted)) !=
-			    acc_mode)
-				goto error;
-
-			if (privused != NULL)
-				*privused = 1;
-			return (0);
-		}
-	}
-
-	/*
-	 * Group match is best-match, not first-match, so find a 
-	 * "best" match.  Iterate across, testing each potential group
-	 * match.  Make sure we keep track of whether we found a match
-	 * or not, so that we know if we should try again with any
-	 * available privilege, or if we should move on to ACL_OTHER.
-	 */
-	group_matched = 0;
-	for (i = 0; i < acl->acl_cnt; i++) {
-		switch (acl->acl_entry[i].ae_tag) {
-		case ACL_GROUP_OBJ:
-			if (!groupmember(file_gid, cred))
-				break;
-			dac_granted = 0;
-			if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
-				dac_granted |= VEXEC;
-			if (acl->acl_entry[i].ae_perm & ACL_READ)
-				dac_granted |= VREAD;
-			if (acl->acl_entry[i].ae_perm & ACL_WRITE)
-				dac_granted |= (VWRITE | VAPPEND);
-			dac_granted  &= acl_mask_granted;
-
-			if ((acc_mode & dac_granted) == acc_mode)
-				return (0);
-
-			group_matched = 1;
-			break;
-
-		case ACL_GROUP:
-			if (!groupmember(acl->acl_entry[i].ae_id, cred))
-				break;
-			dac_granted = 0;
-			if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
-				dac_granted |= VEXEC;
-			if (acl->acl_entry[i].ae_perm & ACL_READ)
-				dac_granted |= VREAD;
-			if (acl->acl_entry[i].ae_perm & ACL_WRITE)
-				dac_granted |= (VWRITE | VAPPEND);
-			dac_granted  &= acl_mask_granted;
-
-			if ((acc_mode & dac_granted) == acc_mode)
-				return (0);
-
-			group_matched = 1;
-			break;
-
-		default:
-			break;
-		}
-	}
-
-	if (group_matched == 1) {
-		/*
-		 * There was a match, but it did not grant rights via
-		 * pure DAC.  Try again, this time with privilege.
-		 */
-		for (i = 0; i < acl->acl_cnt; i++) {
-			switch (acl->acl_entry[i].ae_tag) {
-			case ACL_GROUP_OBJ:
-				if (!groupmember(file_gid, cred))
-					break;
-				dac_granted = 0;
-				if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
-					dac_granted |= VEXEC;
-				if (acl->acl_entry[i].ae_perm & ACL_READ)
-					dac_granted |= VREAD;
-				if (acl->acl_entry[i].ae_perm & ACL_WRITE)
-					dac_granted |= (VWRITE | VAPPEND);
-				dac_granted &= acl_mask_granted;
-
-				if ((acc_mode & (dac_granted | cap_granted)) !=
-				    acc_mode)
-					break;
-
-				if (privused != NULL)
-					*privused = 1;
-				return (0);
-
-			case ACL_GROUP:
-				if (!groupmember(acl->acl_entry[i].ae_id,
-				    cred))
-					break;
-				dac_granted = 0;
-				if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
-				dac_granted |= VEXEC;
-				if (acl->acl_entry[i].ae_perm & ACL_READ)
-					dac_granted |= VREAD;
-				if (acl->acl_entry[i].ae_perm & ACL_WRITE)
-					dac_granted |= (VWRITE | VAPPEND);
-				dac_granted &= acl_mask_granted;
-
-				if ((acc_mode & (dac_granted | cap_granted)) !=
-				    acc_mode)
-					break;
-
-				if (privused != NULL)
-					*privused = 1;
-				return (0);
-
-			default:
-				break;
-			}
-		}
-		/*
-		 * Even with privilege, group membership was not sufficient.
-		 * Return failure.
-		 */
-		goto error;
-	}
-		
-	/*
-	 * Fall back on ACL_OTHER.  ACL_MASK is not applied to ACL_OTHER.
-	 */
-	dac_granted = 0;
-	if (acl_other->ae_perm & ACL_EXECUTE)
-		dac_granted |= VEXEC;
-	if (acl_other->ae_perm & ACL_READ)
-		dac_granted |= VREAD;
-	if (acl_other->ae_perm & ACL_WRITE)
-		dac_granted |= (VWRITE | VAPPEND);
-
-	if ((acc_mode & dac_granted) == acc_mode)
-		return (0);
-	if ((acc_mode & (dac_granted | cap_granted)) == acc_mode) {
-		if (privused != NULL)
-			*privused = 1;
-		return (0);
-	}
-
-error:
-	return ((acc_mode & VADMIN) ? EPERM : EACCES);
-}
-
-/*
- * For the purposes of filesystems maintaining the _OBJ entries in an
- * inode with a mode_t field, this routine converts a mode_t entry
- * to an acl_perm_t.
- */
-acl_perm_t
-acl_posix1e_mode_to_perm(acl_tag_t tag, mode_t mode)
-{
-	acl_perm_t	perm = 0;
-
-	switch(tag) {
-	case ACL_USER_OBJ:
-		if (mode & S_IXUSR)
-			perm |= ACL_EXECUTE;
-		if (mode & S_IRUSR)
-			perm |= ACL_READ;
-		if (mode & S_IWUSR)
-			perm |= ACL_WRITE;
-		return (perm);
-
-	case ACL_GROUP_OBJ:
-		if (mode & S_IXGRP)
-			perm |= ACL_EXECUTE;
-		if (mode & S_IRGRP)
-			perm |= ACL_READ;
-		if (mode & S_IWGRP)
-			perm |= ACL_WRITE;
-		return (perm);
-
-	case ACL_OTHER:
-		if (mode & S_IXOTH)
-			perm |= ACL_EXECUTE;
-		if (mode & S_IROTH)
-			perm |= ACL_READ;
-		if (mode & S_IWOTH)
-			perm |= ACL_WRITE;
-		return (perm);
-
-	default:
-		printf("acl_posix1e_mode_to_perm: invalid tag (%d)\n", tag);
-		return (0);
-	}
-}
-
-/*
- * Given inode information (uid, gid, mode), return an acl entry of the
- * appropriate type.
- */
-struct acl_entry
-acl_posix1e_mode_to_entry(acl_tag_t tag, uid_t uid, gid_t gid, mode_t mode)
-{
-	struct acl_entry	acl_entry;
-
-	acl_entry.ae_tag = tag;
-	acl_entry.ae_perm = acl_posix1e_mode_to_perm(tag, mode);
-	switch(tag) {
-	case ACL_USER_OBJ:
-		acl_entry.ae_id = uid;
-		break;
-
-	case ACL_GROUP_OBJ:
-		acl_entry.ae_id = gid;
-		break;
-
-	case ACL_OTHER:
-		acl_entry.ae_id = ACL_UNDEFINED_ID;
-		break;
-
-	default:
-		acl_entry.ae_id = ACL_UNDEFINED_ID;
-		printf("acl_posix1e_mode_to_entry: invalid tag (%d)\n", tag);
-	}
-
-	return (acl_entry);
-}
-
-/*
- * Utility function to generate a file mode given appropriate ACL entries.
- */
-mode_t
-acl_posix1e_perms_to_mode(struct acl_entry *acl_user_obj_entry,
-    struct acl_entry *acl_group_obj_entry, struct acl_entry *acl_other_entry)
-{
-	mode_t	mode;
-
-	mode = 0;
-	if (acl_user_obj_entry->ae_perm & ACL_EXECUTE)
-		mode |= S_IXUSR;
-	if (acl_user_obj_entry->ae_perm & ACL_READ)
-		mode |= S_IRUSR;
-	if (acl_user_obj_entry->ae_perm & ACL_WRITE)
-		mode |= S_IWUSR;
-	if (acl_group_obj_entry->ae_perm & ACL_EXECUTE)
-		mode |= S_IXGRP;
-	if (acl_group_obj_entry->ae_perm & ACL_READ)
-		mode |= S_IRGRP;
-	if (acl_group_obj_entry->ae_perm & ACL_WRITE)
-		mode |= S_IWGRP;
-	if (acl_other_entry->ae_perm & ACL_EXECUTE)
-		mode |= S_IXOTH;
-	if (acl_other_entry->ae_perm & ACL_READ)
-		mode |= S_IROTH;
-	if (acl_other_entry->ae_perm & ACL_WRITE)
-		mode |= S_IWOTH;
-
-	return (mode);
-}
-
-/*
- * Utility function to generate a file mode given a complete POSIX.1e
- * access ACL.  Note that if the ACL is improperly formed, this may
- * result in a panic.
- */
-mode_t
-acl_posix1e_acl_to_mode(struct acl *acl)
-{
-	struct acl_entry *acl_mask, *acl_user_obj, *acl_group_obj, *acl_other;
-	int i;
-
-	/*
-	 * Find the ACL entries relevant to a POSIX permission mode.
-	 */
-	acl_user_obj = acl_group_obj = acl_other = acl_mask = NULL;
-	for (i = 0; i < acl->acl_cnt; i++) {
-		switch (acl->acl_entry[i].ae_tag) {
-		case ACL_USER_OBJ:
-			acl_user_obj = &acl->acl_entry[i];
-			break;
-
-		case ACL_GROUP_OBJ:
-			acl_group_obj = &acl->acl_entry[i];
-			break;
-
-		case ACL_OTHER:
-			acl_other = &acl->acl_entry[i];
-			break;
-
-		case ACL_MASK:
-			acl_mask = &acl->acl_entry[i];
-			break;
-
-		case ACL_USER:
-		case ACL_GROUP:
-			break;
-
-		default:
-			panic("acl_posix1e_acl_to_mode: bad ae_tag");
-		}
-	}
-
-	if (acl_user_obj == NULL || acl_group_obj == NULL || acl_other == NULL)
-		panic("acl_posix1e_acl_to_mode: missing base ae_tags");
-
-	/*
-	 * POSIX.1e specifies that if there is an ACL_MASK entry, we replace
-	 * the mode "group" bits with its permissions.  If there isn't, we
-	 * use the ACL_GROUP_OBJ permissions.
-	 */
-	if (acl_mask != NULL)
-		return (acl_posix1e_perms_to_mode(acl_user_obj, acl_mask,
-		    acl_other));
-	else
-		return (acl_posix1e_perms_to_mode(acl_user_obj, acl_group_obj,
-		    acl_other));
-}
-
-/*
- * Perform a syntactic check of the ACL, sufficient to allow an
- * implementing filesystem to determine if it should accept this and
- * rely on the POSIX.1e ACL properties.
- */
-int
-acl_posix1e_check(struct acl *acl)
-{
-	int num_acl_user_obj, num_acl_user, num_acl_group_obj, num_acl_group;
-	int num_acl_mask, num_acl_other, i;
-
-	/*
-	 * Verify that the number of entries does not exceed the maximum
-	 * defined for acl_t.
-	 * Verify that the correct number of various sorts of ae_tags are
-	 * present:
-	 *   Exactly one ACL_USER_OBJ
-	 *   Exactly one ACL_GROUP_OBJ
-	 *   Exactly one ACL_OTHER
-	 *   If any ACL_USER or ACL_GROUP entries appear, then exactly one
-	 *   ACL_MASK entry must also appear.
-	 * Verify that all ae_perm entries are in ACL_PERM_BITS.
-	 * Verify all ae_tag entries are understood by this implementation.
-	 * Note: Does not check for uniqueness of qualifier (ae_id) field.
-	 */
-	num_acl_user_obj = num_acl_user = num_acl_group_obj = num_acl_group =
-	    num_acl_mask = num_acl_other = 0;
-	if (acl->acl_cnt > ACL_MAX_ENTRIES || acl->acl_cnt < 0)
-		return (EINVAL);
-	for (i = 0; i < acl->acl_cnt; i++) {
-		/*
-		 * Check for a valid tag.
-		 */
-		switch(acl->acl_entry[i].ae_tag) {
-		case ACL_USER_OBJ:
-			acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
-			if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
-				return (EINVAL);
-			num_acl_user_obj++;
-			break;
-		case ACL_GROUP_OBJ:
-			acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
-			if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
-				return (EINVAL);
-			num_acl_group_obj++;
-			break;
-		case ACL_USER:
-			if (acl->acl_entry[i].ae_id == ACL_UNDEFINED_ID)
-				return (EINVAL);
-			num_acl_user++;
-			break;
-		case ACL_GROUP:
-			if (acl->acl_entry[i].ae_id == ACL_UNDEFINED_ID)
-				return (EINVAL);
-			num_acl_group++;
-			break;
-		case ACL_OTHER:
-			acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
-			if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
-				return (EINVAL);
-			num_acl_other++;
-			break;
-		case ACL_MASK:
-			acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
-			if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
-				return (EINVAL);
-			num_acl_mask++;
-			break;
-		default:
-			return (EINVAL);
-		}
-		/*
-		 * Check for valid perm entries.
-		 */
-		if ((acl->acl_entry[i].ae_perm | ACL_PERM_BITS) !=
-		    ACL_PERM_BITS)
-			return (EINVAL);
-	}
-	if ((num_acl_user_obj != 1) || (num_acl_group_obj != 1) ||
-	    (num_acl_other != 1) || (num_acl_mask != 0 && num_acl_mask != 1))
-		return (EINVAL);
-	if (((num_acl_group != 0) || (num_acl_user != 0)) &&
-	    (num_acl_mask != 1))
-		return (EINVAL);
-	return (0);
-}
-
-/*
- * Given a requested mode for a new object, and a default ACL, combine
- * the two to produce a new mode.  Be careful not to clear any bits that
- * aren't intended to be affected by the POSIX.1e ACL.  Eventually,
- * this might also take the cmask as an argument, if we push that down
- * into per-filesystem-code.
- */
-mode_t
-acl_posix1e_newfilemode(mode_t cmode, struct acl *dacl)
-{
-	mode_t mode;
-
-	mode = cmode;
-	/*
-	 * The current composition policy is that a permission bit must
-	 * be set in *both* the ACL and the requested creation mode for
-	 * it to appear in the resulting mode/ACL.  First clear any
-	 * possibly effected bits, then reconstruct.
-	 */
-	mode &= ACL_PRESERVE_MASK;
-	mode |= (ACL_OVERRIDE_MASK & cmode & acl_posix1e_acl_to_mode(dacl));
-
-	return (mode);
-}
-
-/*
  * These calls wrap the real vnode operations, and are called by the 
  * syscall code once the syscall has converted the path or file
  * descriptor to a vnode (unlocked).  The aclp pointer is assumed