X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/4452a7af2eac33dbad800bcc91f2399d62c18f53..cb3231590a3c94ab4375e2228bd5e86b0cf1ad7e:/bsd/vfs/vfs_xattr.c diff --git a/bsd/vfs/vfs_xattr.c b/bsd/vfs/vfs_xattr.c index 0ecdcd307..dacd51db9 100644 --- a/bsd/vfs/vfs_xattr.c +++ b/bsd/vfs/vfs_xattr.c @@ -1,8 +1,8 @@ /* - * Copyright (c) 2004-2005 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2004-2012 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ - * + * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in @@ -11,10 +11,10 @@ * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. - * + * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. - * + * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, @@ -22,10 +22,16 @@ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. - * + * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ - +/* + * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce + * support for mandatory and extensible security protections. This notice + * is included in support of clause 2.2 (b) of the Apple Public License, + * Version 2.0. + */ + #include #include @@ -33,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -40,63 +47,130 @@ #include #include #include - #include #include #include +#if CONFIG_MACF +#include +#endif + + +#if NAMEDSTREAMS + +static int shadow_sequence; + /* - * Default xattr support routines. + * We use %p to prevent loss of precision for pointers on varying architectures. */ -static int default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, - int options, vfs_context_t context); -static int default_setxattr(vnode_t vp, const char *name, uio_t uio, - int options, vfs_context_t context); +#define SHADOW_NAME_FMT ".vfs_rsrc_stream_%p%08x%p" +#define SHADOW_DIR_FMT ".vfs_rsrc_streams_%p%x" +#define SHADOW_DIR_CONTAINER "/var/run" -static int default_removexattr(vnode_t vp, const char *name, int options, vfs_context_t context); +#define MAKE_SHADOW_NAME(VP, NAME) \ + snprintf((NAME), sizeof((NAME)), (SHADOW_NAME_FMT), \ + ((void*)(VM_KERNEL_ADDRPERM(VP))), \ + (VP)->v_id, \ + ((void*)(VM_KERNEL_ADDRPERM((VP)->v_data)))) -static int default_listxattr(vnode_t vp, uio_t uio, size_t *size, int options, - vfs_context_t context); +/* The full path to the shadow directory */ +#define MAKE_SHADOW_DIRNAME(VP, NAME) \ + snprintf((NAME), sizeof((NAME)), (SHADOW_DIR_CONTAINER "/" SHADOW_DIR_FMT), \ + ((void*)(VM_KERNEL_ADDRPERM(VP))), shadow_sequence) +/* The shadow directory as a 'leaf' entry */ +#define MAKE_SHADOW_DIR_LEAF(VP, NAME) \ + snprintf((NAME), sizeof((NAME)), (SHADOW_DIR_FMT), \ + ((void*)(VM_KERNEL_ADDRPERM(VP))), shadow_sequence) +static int default_getnamedstream(vnode_t vp, vnode_t *svpp, const char *name, enum nsoperation op, vfs_context_t context); + +static int default_makenamedstream(vnode_t vp, vnode_t *svpp, const char *name, vfs_context_t context); + +static int default_removenamedstream(vnode_t vp, const char *name, vfs_context_t context); + +static int getshadowfile(vnode_t vp, vnode_t *svpp, int makestream, size_t *rsrcsize, int *creator, vfs_context_t context); + +static int get_shadow_dir(vnode_t *sdvpp); + +#endif /* NAMEDSTREAMS */ + +/* + * Default xattr support routines. + */ + +static int default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, int options, + vfs_context_t context); +static int default_setxattr(vnode_t vp, const char *name, uio_t uio, int options, + vfs_context_t context); +static int default_listxattr(vnode_t vp, uio_t uio, size_t *size, int options, + vfs_context_t context); +static int default_removexattr(vnode_t vp, const char *name, int options, + vfs_context_t context); /* * Retrieve the data of an extended attribute. */ int vn_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, - int options, vfs_context_t context) + int options, vfs_context_t context) { int error; - if (!(vp->v_type == VREG || vp->v_type == VDIR || vp->v_type == VLNK)) { - return (EPERM); + if (!XATTR_VNODE_SUPPORTED(vp)) { + return EPERM; } - if ((error = xattr_validatename(name))) { - return (error); - } - if (!(options & XATTR_NOSECURITY) && (error = vnode_authorize(vp, NULL, KAUTH_VNODE_READ_EXTATTRIBUTES, context))) +#if NAMEDSTREAMS + /* getxattr calls are not allowed for streams. */ + if (vp->v_flag & VISNAMEDSTREAM) { + error = EPERM; goto out; + } +#endif + /* + * Non-kernel request need extra checks performed. + * + * The XATTR_NOSECURITY flag implies a kernel request. + */ + if (!(options & XATTR_NOSECURITY)) { +#if CONFIG_MACF + error = mac_vnode_check_getextattr(context, vp, name, uio); + if (error) { + goto out; + } +#endif /* MAC */ + if ((error = xattr_validatename(name))) { + goto out; + } + if ((error = vnode_authorize(vp, NULL, KAUTH_VNODE_READ_EXTATTRIBUTES, context))) { + goto out; + } + /* The offset can only be non-zero for resource forks. */ + if (uio != NULL && uio_offset(uio) != 0 && + bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0) { + error = EINVAL; + goto out; + } + } /* The offset can only be non-zero for resource forks. */ - if (uio != NULL && uio_offset(uio) != 0 && + if (uio != NULL && uio_offset(uio) != 0 && bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0) { error = EINVAL; goto out; } error = VNOP_GETXATTR(vp, name, uio, size, options, context); - if (error == ENOTSUP) { + if (error == ENOTSUP && !(options & XATTR_NODEFAULT)) { /* * A filesystem may keep some EAs natively and return ENOTSUP for others. - * SMB returns ENOTSUP for finderinfo and resource forks. */ error = default_getxattr(vp, name, uio, size, options, context); } out: - return (error); + return error; } /* @@ -107,21 +181,37 @@ vn_setxattr(vnode_t vp, const char *name, uio_t uio, int options, vfs_context_t { int error; - if (!(vp->v_type == VREG || vp->v_type == VDIR || vp->v_type == VLNK)) { - return (EPERM); + if (!XATTR_VNODE_SUPPORTED(vp)) { + return EPERM; } - if ((options & (XATTR_REPLACE|XATTR_CREATE)) == (XATTR_REPLACE|XATTR_CREATE)) { - return (EINVAL); +#if NAMEDSTREAMS + /* setxattr calls are not allowed for streams. */ + if (vp->v_flag & VISNAMEDSTREAM) { + error = EPERM; + goto out; + } +#endif + if ((options & (XATTR_REPLACE | XATTR_CREATE)) == (XATTR_REPLACE | XATTR_CREATE)) { + return EINVAL; } if ((error = xattr_validatename(name))) { - return (error); + return error; + } + if (!(options & XATTR_NOSECURITY)) { +#if CONFIG_MACF + error = mac_vnode_check_setextattr(context, vp, name, uio); + if (error) { + goto out; + } +#endif /* MAC */ + error = vnode_authorize(vp, NULL, KAUTH_VNODE_WRITE_EXTATTRIBUTES, context); + if (error) { + goto out; + } } - if (!(options & XATTR_NOSECURITY) && (error = vnode_authorize(vp, NULL, KAUTH_VNODE_WRITE_EXTATTRIBUTES, context))) - goto out; - /* The offset can only be non-zero for resource forks. */ - if (uio_offset(uio) != 0 && - bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0 ) { + if (uio_offset(uio) != 0 && + bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0) { error = EINVAL; goto out; } @@ -139,7 +229,7 @@ vn_setxattr(vnode_t vp, const char *name, uio_t uio, int options, vfs_context_t */ if (error == EJUSTRETURN) { int native = 0, dufile = 0; - size_t sz; /* not used */ + size_t sz; /* not used */ native = VNOP_GETXATTR(vp, name, NULL, &sz, 0, context) ? 0 : 1; dufile = default_getxattr(vp, name, NULL, &sz, 0, context) ? 0 : 1; @@ -160,15 +250,22 @@ vn_setxattr(vnode_t vp, const char *name, uio_t uio, int options, vfs_context_t /* the mainline path here is to have error==ENOTSUP ... */ } #endif /* DUAL_EAS */ - if (error == ENOTSUP) { + if (error == ENOTSUP && !(options & XATTR_NODEFAULT)) { /* * A filesystem may keep some EAs natively and return ENOTSUP for others. - * SMB returns ENOTSUP for finderinfo and resource forks. */ error = default_setxattr(vp, name, uio, options, context); } +#if CONFIG_MACF + if ((error == 0) && !(options & XATTR_NOSECURITY)) { + mac_vnode_notify_setextattr(context, vp, name, uio); + if (vfs_flags(vnode_mount(vp)) & MNT_MULTILABEL) { + mac_vnode_label_update_extattr(vnode_mount(vp), vp, name); + } + } +#endif out: - return (error); + return error; } /* @@ -179,19 +276,35 @@ vn_removexattr(vnode_t vp, const char * name, int options, vfs_context_t context { int error; - if (!(vp->v_type == VREG || vp->v_type == VDIR || vp->v_type == VLNK)) { - return (EPERM); + if (!XATTR_VNODE_SUPPORTED(vp)) { + return EPERM; + } +#if NAMEDSTREAMS + /* removexattr calls are not allowed for streams. */ + if (vp->v_flag & VISNAMEDSTREAM) { + error = EPERM; + goto out; } +#endif if ((error = xattr_validatename(name))) { - return (error); + return error; + } + if (!(options & XATTR_NOSECURITY)) { +#if CONFIG_MACF + error = mac_vnode_check_deleteextattr(context, vp, name); + if (error) { + goto out; + } +#endif /* MAC */ + error = vnode_authorize(vp, NULL, KAUTH_VNODE_WRITE_EXTATTRIBUTES, context); + if (error) { + goto out; + } } - if (!(options & XATTR_NOSECURITY) && (error = vnode_authorize(vp, NULL, KAUTH_VNODE_WRITE_EXTATTRIBUTES, context))) - goto out; error = VNOP_REMOVEXATTR(vp, name, options, context); - if (error == ENOTSUP) { + if (error == ENOTSUP && !(options & XATTR_NODEFAULT)) { /* * A filesystem may keep some EAs natively and return ENOTSUP for others. - * SMB returns ENOTSUP for finderinfo and resource forks. */ error = default_removexattr(vp, name, options, context); #ifdef DUAL_EAS @@ -203,12 +316,21 @@ vn_removexattr(vnode_t vp, const char * name, int options, vfs_context_t context * default_removexattr should not be considered an error. */ error = default_removexattr(vp, name, options, context); - if (error == ENOATTR) + if (error == ENOATTR) { error = 0; + } #endif /* DUAL_EAS */ } +#if CONFIG_MACF + if ((error == 0) && !(options & XATTR_NOSECURITY)) { + mac_vnode_notify_deleteextattr(context, vp, name); + if (vfs_flags(vnode_mount(vp)) & MNT_MULTILABEL) { + mac_vnode_label_update_extattr(vnode_mount(vp), vp, name); + } + } +#endif out: - return (error); + return error; } /* @@ -219,24 +341,41 @@ vn_listxattr(vnode_t vp, uio_t uio, size_t *size, int options, vfs_context_t con { int error; - if (!(vp->v_type == VREG || vp->v_type == VDIR || vp->v_type == VLNK)) { - return (EPERM); + if (!XATTR_VNODE_SUPPORTED(vp)) { + return EPERM; + } +#if NAMEDSTREAMS + /* listxattr calls are not allowed for streams. */ + if (vp->v_flag & VISNAMEDSTREAM) { + return EPERM; + } +#endif + + if (!(options & XATTR_NOSECURITY)) { +#if CONFIG_MACF + error = mac_vnode_check_listextattr(context, vp); + if (error) { + goto out; + } +#endif /* MAC */ + + error = vnode_authorize(vp, NULL, KAUTH_VNODE_READ_EXTATTRIBUTES, context); + if (error) { + goto out; + } } - if (!(options & XATTR_NOSECURITY) && (error = vnode_authorize(vp, NULL, KAUTH_VNODE_READ_EXTATTRIBUTES, context))) - goto out; error = VNOP_LISTXATTR(vp, uio, size, options, context); - if (error == ENOTSUP) { + if (error == ENOTSUP && !(options & XATTR_NODEFAULT)) { /* * A filesystem may keep some but not all EAs natively, in which case * the native EA names will have been uiomove-d out (or *size updated) - * and the default_listxattr here will finish the job. Note SMB takes - * advantage of this for its finder-info and resource forks. + * and the default_listxattr here will finish the job. */ error = default_listxattr(vp, uio, size, options, context); } out: - return (error); + return error; } int @@ -245,16 +384,18 @@ xattr_validatename(const char *name) int namelen; if (name == NULL || name[0] == '\0') { - return (EINVAL); + return EINVAL; } namelen = strlen(name); - if (namelen > XATTR_MAXNAMELEN) { - return (ENAMETOOLONG); + if (name[namelen] != '\0') { + return ENAMETOOLONG; } - if (utf8_validatestr(name, namelen) != 0) { - return (EINVAL); + + if (utf8_validatestr((const unsigned char *)name, namelen) != 0) { + return EINVAL; } - return (0); + + return 0; } @@ -264,63 +405,893 @@ xattr_validatename(const char *name) int xattr_protected(const char *attrname) { - return(!strncmp(attrname, "com.apple.system.", 17)); + return !strncmp(attrname, "com.apple.system.", 17); +} + + +static void +vnode_setasnamedstream_internal(vnode_t vp, vnode_t svp) +{ + uint32_t streamflags = VISNAMEDSTREAM; + + if ((vp->v_mount->mnt_kern_flag & MNTK_NAMED_STREAMS) == 0) { + streamflags |= VISSHADOW; + } + + /* Tag the vnode. */ + vnode_lock_spin(svp); + svp->v_flag |= streamflags; + vnode_unlock(svp); + + /* Tag the parent so we know to flush credentials for streams on setattr */ + vnode_lock_spin(vp); + vp->v_lflag |= VL_HASSTREAMS; + vnode_unlock(vp); + + /* Make the file it's parent. + * Note: This parent link helps us distinguish vnodes for + * shadow stream files from vnodes for resource fork on file + * systems that support namedstream natively (both have + * VISNAMEDSTREAM set) by allowing access to mount structure + * for checking MNTK_NAMED_STREAMS bit at many places in the + * code. + */ + vnode_update_identity(svp, vp, NULL, 0, 0, VNODE_UPDATE_NAMEDSTREAM_PARENT); + + return; +} + +errno_t +vnode_setasnamedstream(vnode_t vp, vnode_t svp) +{ + if ((vp->v_mount->mnt_kern_flag & MNTK_NAMED_STREAMS) == 0) { + return EINVAL; + } + + vnode_setasnamedstream_internal(vp, svp); + return 0; +} + +#if NAMEDSTREAMS + +/* + * Obtain a named stream from vnode vp. + */ +errno_t +vnode_getnamedstream(vnode_t vp, vnode_t *svpp, const char *name, enum nsoperation op, int flags, vfs_context_t context) +{ + int error; + + if (vp->v_mount->mnt_kern_flag & MNTK_NAMED_STREAMS) { + error = VNOP_GETNAMEDSTREAM(vp, svpp, name, op, flags, context); + } else { + if (flags) { + error = ENOTSUP; + } else { + error = default_getnamedstream(vp, svpp, name, op, context); + } + } + + if (error == 0) { + vnode_setasnamedstream_internal(vp, *svpp); + } + + return error; +} + +/* + * Make a named stream for vnode vp. + */ +errno_t +vnode_makenamedstream(vnode_t vp, vnode_t *svpp, const char *name, int flags, vfs_context_t context) +{ + int error; + + if (vp->v_mount->mnt_kern_flag & MNTK_NAMED_STREAMS) { + error = VNOP_MAKENAMEDSTREAM(vp, svpp, name, flags, context); + } else { + error = default_makenamedstream(vp, svpp, name, context); + } + + if (error == 0) { + vnode_setasnamedstream_internal(vp, *svpp); + } + + return error; } +/* + * Remove a named stream from vnode vp. + */ +errno_t +vnode_removenamedstream(vnode_t vp, vnode_t svp, const char *name, int flags, vfs_context_t context) +{ + int error; + + if (vp->v_mount->mnt_kern_flag & MNTK_NAMED_STREAMS) { + error = VNOP_REMOVENAMEDSTREAM(vp, svp, name, flags, context); + } else { + error = default_removenamedstream(vp, name, context); + } + + return error; +} + +#define NS_IOBUFSIZE (128 * 1024) + +/* + * Release a named stream shadow file. + * + * Note: This function is called from two places where we do not need + * to check if the vnode has any references held before deleting the + * shadow file. Once from vclean() when the vnode is being reclaimed + * and we do not hold any references on the vnode. Second time from + * default_getnamedstream() when we get an error during shadow stream + * file initialization so that other processes who are waiting for the + * shadow stream file initialization by the creator will get opportunity + * to create and initialize the file again. + */ +errno_t +vnode_relenamedstream(vnode_t vp, vnode_t svp) +{ + vnode_t dvp; + struct componentname cn; + char tmpname[80]; + errno_t err; + + /* + * We need to use the kernel context here. If we used the supplied + * VFS context we have no clue whether or not it originated from userland + * where it could be subject to a chroot jail. We need to ensure that all + * filesystem access to shadow files is done on the same FS regardless of + * userland process restrictions. + */ + vfs_context_t kernelctx = vfs_context_kernel(); + + cache_purge(svp); + + vnode_lock(svp); + MAKE_SHADOW_NAME(vp, tmpname); + vnode_unlock(svp); + + cn.cn_nameiop = DELETE; + cn.cn_flags = ISLASTCN; + cn.cn_context = kernelctx; + cn.cn_pnbuf = tmpname; + cn.cn_pnlen = sizeof(tmpname); + cn.cn_nameptr = cn.cn_pnbuf; + cn.cn_namelen = strlen(tmpname); + + /* + * Obtain the vnode for the shadow files directory. Make sure to + * use the kernel ctx as described above. + */ + err = get_shadow_dir(&dvp); + if (err != 0) { + return err; + } + + (void) VNOP_REMOVE(dvp, svp, &cn, 0, kernelctx); + vnode_put(dvp); + + return 0; +} + +/* + * Flush a named stream shadow file. + * + * 'vp' represents the AppleDouble file. + * 'svp' represents the shadow file. + */ +errno_t +vnode_flushnamedstream(vnode_t vp, vnode_t svp, vfs_context_t context) +{ + struct vnode_attr va; + uio_t auio = NULL; + caddr_t bufptr = NULL; + size_t bufsize = 0; + size_t offset; + size_t iosize; + size_t datasize; + int error; + /* + * The kernel context must be used for all I/O to the shadow file + * and its namespace operations + */ + vfs_context_t kernelctx = vfs_context_kernel(); + + /* The supplied context is used for access to the AD file itself */ + + VATTR_INIT(&va); + VATTR_WANTED(&va, va_data_size); + if (VNOP_GETATTR(svp, &va, context) != 0 || + !VATTR_IS_SUPPORTED(&va, va_data_size)) { + return 0; + } + datasize = va.va_data_size; + if (datasize == 0) { + (void) default_removexattr(vp, XATTR_RESOURCEFORK_NAME, 0, context); + return 0; + } + + iosize = bufsize = MIN(datasize, NS_IOBUFSIZE); + if (kmem_alloc(kernel_map, (vm_offset_t *)&bufptr, bufsize, VM_KERN_MEMORY_FILE)) { + return ENOMEM; + } + auio = uio_create(1, 0, UIO_SYSSPACE, UIO_READ); + offset = 0; + + /* + * Copy the shadow stream file data into the resource fork. + */ + error = VNOP_OPEN(svp, 0, kernelctx); + if (error) { + printf("vnode_flushnamedstream: err %d opening file\n", error); + goto out; + } + while (offset < datasize) { + iosize = MIN(datasize - offset, iosize); + + uio_reset(auio, offset, UIO_SYSSPACE, UIO_READ); + uio_addiov(auio, (uintptr_t)bufptr, iosize); + error = VNOP_READ(svp, auio, 0, kernelctx); + if (error) { + break; + } + /* Since there's no truncate xattr we must remove the resource fork. */ + if (offset == 0) { + error = default_removexattr(vp, XATTR_RESOURCEFORK_NAME, 0, context); + if ((error != 0) && (error != ENOATTR)) { + break; + } + } + uio_reset(auio, offset, UIO_SYSSPACE, UIO_WRITE); + uio_addiov(auio, (uintptr_t)bufptr, iosize); + error = vn_setxattr(vp, XATTR_RESOURCEFORK_NAME, auio, XATTR_NOSECURITY, context); + if (error) { + break; + } + offset += iosize; + } + + /* close shadowfile */ + (void) VNOP_CLOSE(svp, 0, kernelctx); +out: + if (bufptr) { + kmem_free(kernel_map, (vm_offset_t)bufptr, bufsize); + } + if (auio) { + uio_free(auio); + } + return error; +} + + +/* + * Verify that the vnode 'vp' is a vnode that lives in the shadow + * directory. We can't just query the parent pointer directly since + * the shadowfile is hooked up to the actual file it's a stream for. + */ +errno_t +vnode_verifynamedstream(vnode_t vp) +{ + int error; + struct vnode *shadow_dvp = NULL; + struct vnode *shadowfile = NULL; + struct componentname cn; + + /* + * We need to use the kernel context here. If we used the supplied + * VFS context we have no clue whether or not it originated from userland + * where it could be subject to a chroot jail. We need to ensure that all + * filesystem access to shadow files is done on the same FS regardless of + * userland process restrictions. + */ + vfs_context_t kernelctx = vfs_context_kernel(); + char tmpname[80]; + + + /* Get the shadow directory vnode */ + error = get_shadow_dir(&shadow_dvp); + if (error) { + return error; + } + + /* Re-generate the shadow name in the buffer */ + MAKE_SHADOW_NAME(vp, tmpname); + + /* Look up item in shadow dir */ + bzero(&cn, sizeof(cn)); + cn.cn_nameiop = LOOKUP; + cn.cn_flags = ISLASTCN | CN_ALLOWRSRCFORK; + cn.cn_context = kernelctx; + cn.cn_pnbuf = tmpname; + cn.cn_pnlen = sizeof(tmpname); + cn.cn_nameptr = cn.cn_pnbuf; + cn.cn_namelen = strlen(tmpname); + + if (VNOP_LOOKUP(shadow_dvp, &shadowfile, &cn, kernelctx) == 0) { + /* is the pointer the same? */ + if (shadowfile == vp) { + error = 0; + } else { + error = EPERM; + } + /* drop the iocount acquired */ + vnode_put(shadowfile); + } + + /* Drop iocount on shadow dir */ + vnode_put(shadow_dvp); + return error; +} /* - * Default Implementation (Non-native EA) + * Access or create the shadow file as needed. + * + * 'makestream' with non-zero value means that we need to guarantee we were the + * creator of the shadow file. + * + * 'context' is the user supplied context for the original VFS operation that + * caused us to need a shadow file. + * + * int pointed to by 'creator' is nonzero if we created the shadowfile. */ +static int +getshadowfile(vnode_t vp, vnode_t *svpp, int makestream, size_t *rsrcsize, + int *creator, vfs_context_t context) +{ + vnode_t dvp = NULLVP; + vnode_t svp = NULLVP; + struct componentname cn; + struct vnode_attr va; + char tmpname[80]; + size_t datasize = 0; + int error = 0; + int retries = 0; + vfs_context_t kernelctx = vfs_context_kernel(); + +retry_create: + *creator = 0; + /* Establish a unique file name. */ + MAKE_SHADOW_NAME(vp, tmpname); + bzero(&cn, sizeof(cn)); + cn.cn_nameiop = LOOKUP; + cn.cn_flags = ISLASTCN; + cn.cn_context = context; + cn.cn_pnbuf = tmpname; + cn.cn_pnlen = sizeof(tmpname); + cn.cn_nameptr = cn.cn_pnbuf; + cn.cn_namelen = strlen(tmpname); + + /* Pick up uid, gid, mode and date from original file. */ + VATTR_INIT(&va); + VATTR_WANTED(&va, va_uid); + VATTR_WANTED(&va, va_gid); + VATTR_WANTED(&va, va_mode); + VATTR_WANTED(&va, va_create_time); + VATTR_WANTED(&va, va_modify_time); + if (VNOP_GETATTR(vp, &va, context) != 0 || + !VATTR_IS_SUPPORTED(&va, va_uid) || + !VATTR_IS_SUPPORTED(&va, va_gid) || + !VATTR_IS_SUPPORTED(&va, va_mode)) { + va.va_uid = KAUTH_UID_NONE; + va.va_gid = KAUTH_GID_NONE; + va.va_mode = S_IRUSR | S_IWUSR; + } + va.va_vaflags = VA_EXCLUSIVE; + VATTR_SET(&va, va_type, VREG); + /* We no longer change the access, but we still hide it. */ + VATTR_SET(&va, va_flags, UF_HIDDEN); + + /* Obtain the vnode for the shadow files directory. */ + if (get_shadow_dir(&dvp) != 0) { + error = ENOTDIR; + goto out; + } + if (!makestream) { + /* See if someone else already has it open. */ + if (VNOP_LOOKUP(dvp, &svp, &cn, kernelctx) == 0) { + /* Double check existence by asking for size. */ + VATTR_INIT(&va); + VATTR_WANTED(&va, va_data_size); + if (VNOP_GETATTR(svp, &va, context) == 0 && + VATTR_IS_SUPPORTED(&va, va_data_size)) { + goto out; /* OK to use. */ + } + } + + /* + * Otherwise make sure the resource fork data exists. + * Use the supplied context for accessing the AD file. + */ + error = vn_getxattr(vp, XATTR_RESOURCEFORK_NAME, NULL, &datasize, + XATTR_NOSECURITY, context); + /* + * To maintain binary compatibility with legacy Carbon + * emulated resource fork support, if the resource fork + * doesn't exist but the Finder Info does, then act as + * if an empty resource fork is present (see 4724359). + */ + if ((error == ENOATTR) && + (vn_getxattr(vp, XATTR_FINDERINFO_NAME, NULL, &datasize, + XATTR_NOSECURITY, context) == 0)) { + datasize = 0; + error = 0; + } else { + if (error) { + goto out; + } + + /* If the resource fork exists, its size is expected to be non-zero. */ + if (datasize == 0) { + error = ENOATTR; + goto out; + } + } + } + /* Create the shadow stream file. */ + error = VNOP_CREATE(dvp, &svp, &cn, &va, kernelctx); + if (error == 0) { + vnode_recycle(svp); + *creator = 1; + } else if ((error == EEXIST) && !makestream) { + error = VNOP_LOOKUP(dvp, &svp, &cn, kernelctx); + } else if ((error == ENOENT) && !makestream) { + /* + * We could have raced with a rmdir on the shadow directory + * post-lookup. Retry from the beginning, 1x only, to + * try and see if we need to re-create the shadow directory + * in get_shadow_dir. + */ + if (retries == 0) { + retries++; + if (dvp) { + vnode_put(dvp); + dvp = NULLVP; + } + if (svp) { + vnode_put(svp); + svp = NULLVP; + } + goto retry_create; + } + /* Otherwise, just error out normally below */ + } + +out: + if (dvp) { + vnode_put(dvp); + } + if (error) { + /* On errors, clean up shadow stream file. */ + if (svp) { + vnode_put(svp); + svp = NULLVP; + } + } + *svpp = svp; + if (rsrcsize) { + *rsrcsize = datasize; + } + return error; +} + + +static int +default_getnamedstream(vnode_t vp, vnode_t *svpp, const char *name, enum nsoperation op, vfs_context_t context) +{ + vnode_t svp = NULLVP; + uio_t auio = NULL; + caddr_t bufptr = NULL; + size_t bufsize = 0; + size_t datasize = 0; + int creator; + int error; + + /* need the kernel context for accessing the shadowfile */ + vfs_context_t kernelctx = vfs_context_kernel(); + + /* + * Only the "com.apple.ResourceFork" stream is supported here. + */ + if (bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0) { + *svpp = NULLVP; + return ENOATTR; + } +retry: + /* + * Obtain a shadow file for the resource fork I/O. + * + * Need to pass along the supplied context so that getshadowfile + * can access the AD file as needed, using it. + */ + error = getshadowfile(vp, &svp, 0, &datasize, &creator, context); + if (error) { + *svpp = NULLVP; + return error; + } + + /* + * The creator of the shadow file provides its file data, + * all other threads should wait until its ready. In order to + * prevent a deadlock during error codepaths, we need to check if the + * vnode is being created, or if it has failed out. Regardless of success or + * failure, we set the VISSHADOW bit on the vnode, so we check that + * if the vnode's flags don't have VISNAMEDSTREAM set. If it doesn't, + * then we can infer the creator isn't done yet. If it's there, but + * VISNAMEDSTREAM is not set, then we can infer it errored out and we should + * try again. + */ + if (!creator) { + vnode_lock(svp); + if (svp->v_flag & VISNAMEDSTREAM) { + /* data is ready, go use it */ + vnode_unlock(svp); + goto out; + } else { + /* It's not ready, wait for it (sleep using v_parent as channel) */ + if ((svp->v_flag & VISSHADOW)) { + /* + * No VISNAMEDSTREAM, but we did see VISSHADOW, indicating that the other + * thread is done with this vnode. Just unlock the vnode and try again + */ + vnode_unlock(svp); + } else { + /* Otherwise, sleep if the shadow file is not created yet */ + msleep((caddr_t)&svp->v_parent, &svp->v_lock, PINOD | PDROP, + "getnamedstream", NULL); + } + vnode_put(svp); + svp = NULLVP; + goto retry; + } + } + + /* + * Copy the real resource fork data into shadow stream file. + */ + if (op == NS_OPEN && datasize != 0) { + size_t offset; + size_t iosize; + + iosize = bufsize = MIN(datasize, NS_IOBUFSIZE); + if (kmem_alloc(kernel_map, (vm_offset_t *)&bufptr, bufsize, VM_KERN_MEMORY_FILE)) { + error = ENOMEM; + goto out; + } + + auio = uio_create(1, 0, UIO_SYSSPACE, UIO_READ); + offset = 0; + + /* open the shadow file */ + error = VNOP_OPEN(svp, 0, kernelctx); + if (error) { + goto out; + } + while (offset < datasize) { + size_t tmpsize; + + iosize = MIN(datasize - offset, iosize); + + uio_reset(auio, offset, UIO_SYSSPACE, UIO_READ); + uio_addiov(auio, (uintptr_t)bufptr, iosize); + /* use supplied ctx for AD file */ + error = vn_getxattr(vp, XATTR_RESOURCEFORK_NAME, auio, &tmpsize, + XATTR_NOSECURITY, context); + if (error) { + break; + } + + uio_reset(auio, offset, UIO_SYSSPACE, UIO_WRITE); + uio_addiov(auio, (uintptr_t)bufptr, iosize); + /* kernel context for writing shadowfile */ + error = VNOP_WRITE(svp, auio, 0, kernelctx); + if (error) { + break; + } + offset += iosize; + } + + /* close shadow file */ + (void) VNOP_CLOSE(svp, 0, kernelctx); + } +out: + /* Wake up anyone waiting for svp file content */ + if (creator) { + if (error == 0) { + vnode_lock(svp); + /* VISSHADOW would be set later on anyway, so we set it now */ + svp->v_flag |= (VISNAMEDSTREAM | VISSHADOW); + wakeup((caddr_t)&svp->v_parent); + vnode_unlock(svp); + } else { + /* On post create errors, get rid of the shadow file. This + * way if there is another process waiting for initialization + * of the shadowfile by the current process will wake up and + * retry by creating and initializing the shadow file again. + * Also add the VISSHADOW bit here to indicate we're done operating + * on this vnode. + */ + (void)vnode_relenamedstream(vp, svp); + vnode_lock(svp); + svp->v_flag |= VISSHADOW; + wakeup((caddr_t)&svp->v_parent); + vnode_unlock(svp); + } + } + + if (bufptr) { + kmem_free(kernel_map, (vm_offset_t)bufptr, bufsize); + } + if (auio) { + uio_free(auio); + } + if (error) { + /* On errors, clean up shadow stream file. */ + if (svp) { + vnode_put(svp); + svp = NULLVP; + } + } + *svpp = svp; + return error; +} + +static int +default_makenamedstream(vnode_t vp, vnode_t *svpp, const char *name, vfs_context_t context) +{ + int creator; + int error; + + /* + * Only the "com.apple.ResourceFork" stream is supported here. + */ + if (bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0) { + *svpp = NULLVP; + return ENOATTR; + } + + /* Supply the context to getshadowfile so it can manipulate the AD file */ + error = getshadowfile(vp, svpp, 1, NULL, &creator, context); + /* + * Wake up any waiters over in default_getnamedstream(). + */ + if ((error == 0) && (*svpp != NULL) && creator) { + vnode_t svp = *svpp; + + vnode_lock(svp); + /* If we're the creator, mark it as a named stream */ + svp->v_flag |= (VISNAMEDSTREAM | VISSHADOW); + /* Wakeup any waiters on the v_parent channel */ + wakeup((caddr_t)&svp->v_parent); + vnode_unlock(svp); + } + + return error; +} + +static int +default_removenamedstream(vnode_t vp, const char *name, vfs_context_t context) +{ + /* + * Only the "com.apple.ResourceFork" stream is supported here. + */ + if (bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) != 0) { + return ENOATTR; + } + /* + * XXX - what about other opened instances? + */ + return default_removexattr(vp, XATTR_RESOURCEFORK_NAME, 0, context); +} + +static int +get_shadow_dir(vnode_t *sdvpp) +{ + vnode_t dvp = NULLVP; + vnode_t sdvp = NULLVP; + struct componentname cn; + struct vnode_attr va; + char tmpname[80]; + uint32_t tmp_fsid; + int error; + vfs_context_t kernelctx = vfs_context_kernel(); + + bzero(tmpname, sizeof(tmpname)); + MAKE_SHADOW_DIRNAME(rootvnode, tmpname); + /* + * Look up the shadow directory to ensure that it still exists. + * By looking it up, we get an iocounted dvp to use, and avoid some coherency issues + * in caching it when multiple threads may be trying to manipulate the pointers. + * + * Make sure to use the kernel context. We want a singular view of + * the shadow dir regardless of chrooted processes. + */ + error = vnode_lookup(tmpname, 0, &sdvp, kernelctx); + if (error == 0) { + /* + * If we get here, then we have successfully looked up the shadow dir, + * and it has an iocount from the lookup. Return the vp in the output argument. + */ + *sdvpp = sdvp; + return 0; + } + /* In the failure case, no iocount is acquired */ + sdvp = NULLVP; + bzero(tmpname, sizeof(tmpname)); + + /* + * Obtain the vnode for "/var/run" directory using the kernel + * context. + * + * This is defined in the SHADOW_DIR_CONTAINER macro + */ + if (vnode_lookup(SHADOW_DIR_CONTAINER, 0, &dvp, kernelctx) != 0) { + error = ENOTSUP; + goto out; + } + /* + * Create the shadow stream directory. + * 'dvp' below suggests the parent directory so + * we only need to provide the leaf entry name + */ + MAKE_SHADOW_DIR_LEAF(rootvnode, tmpname); + bzero(&cn, sizeof(cn)); + cn.cn_nameiop = LOOKUP; + cn.cn_flags = ISLASTCN; + cn.cn_context = kernelctx; + cn.cn_pnbuf = tmpname; + cn.cn_pnlen = sizeof(tmpname); + cn.cn_nameptr = cn.cn_pnbuf; + cn.cn_namelen = strlen(tmpname); + + /* + * owned by root, only readable by root, hidden + */ + VATTR_INIT(&va); + VATTR_SET(&va, va_uid, 0); + VATTR_SET(&va, va_gid, 0); + VATTR_SET(&va, va_mode, S_IRUSR | S_IXUSR); + VATTR_SET(&va, va_type, VDIR); + VATTR_SET(&va, va_flags, UF_HIDDEN); + va.va_vaflags = VA_EXCLUSIVE; + + error = VNOP_MKDIR(dvp, &sdvp, &cn, &va, kernelctx); + + /* + * There can be only one winner for an exclusive create. + */ + if (error == EEXIST) { + /* loser has to look up directory */ + error = VNOP_LOOKUP(dvp, &sdvp, &cn, kernelctx); + if (error == 0) { + /* Make sure its in fact a directory */ + if (sdvp->v_type != VDIR) { + goto baddir; + } + /* Obtain the fsid for /var/run directory */ + VATTR_INIT(&va); + VATTR_WANTED(&va, va_fsid); + if (VNOP_GETATTR(dvp, &va, kernelctx) != 0 || + !VATTR_IS_SUPPORTED(&va, va_fsid)) { + goto baddir; + } + tmp_fsid = va.va_fsid; + + VATTR_INIT(&va); + VATTR_WANTED(&va, va_uid); + VATTR_WANTED(&va, va_gid); + VATTR_WANTED(&va, va_mode); + VATTR_WANTED(&va, va_fsid); + VATTR_WANTED(&va, va_dirlinkcount); + VATTR_WANTED(&va, va_acl); + /* Provide defaults for attrs that may not be supported */ + va.va_dirlinkcount = 1; + va.va_acl = (kauth_acl_t) KAUTH_FILESEC_NONE; + + if (VNOP_GETATTR(sdvp, &va, kernelctx) != 0 || + !VATTR_IS_SUPPORTED(&va, va_uid) || + !VATTR_IS_SUPPORTED(&va, va_gid) || + !VATTR_IS_SUPPORTED(&va, va_mode) || + !VATTR_IS_SUPPORTED(&va, va_fsid)) { + goto baddir; + } + /* + * Make sure its what we want: + * - owned by root + * - not writable by anyone + * - on same file system as /var/run + * - not a hard-linked directory + * - no ACLs (they might grant write access) + */ + if ((va.va_uid != 0) || (va.va_gid != 0) || + (va.va_mode & (S_IWUSR | S_IRWXG | S_IRWXO)) || + (va.va_fsid != tmp_fsid) || + (va.va_dirlinkcount != 1) || + (va.va_acl != (kauth_acl_t) KAUTH_FILESEC_NONE)) { + goto baddir; + } + } + } +out: + if (dvp) { + vnode_put(dvp); + } + if (error) { + /* On errors, clean up shadow stream directory. */ + if (sdvp) { + vnode_put(sdvp); + sdvp = NULLVP; + } + } + *sdvpp = sdvp; + return error; + +baddir: + /* This is not the dir we're looking for, move along */ + ++shadow_sequence; /* try something else next time */ + error = ENOTDIR; + goto out; +} +#endif /* NAMEDSTREAMS */ + + +#if CONFIG_APPLEDOUBLE /* - Typical "._" AppleDouble Header File layout: - ------------------------------------------------------------ - MAGIC 0x00051607 - VERSION 0x00020000 - FILLER 0 - COUNT 2 - .-- AD ENTRY[0] Finder Info Entry (must be first) - .--+-- AD ENTRY[1] Resource Fork Entry (must be last) - | '-> FINDER INFO - | ///////////// Fixed Size Data (32 bytes) - | EXT ATTR HDR - | ///////////// - | ATTR ENTRY[0] --. - | ATTR ENTRY[1] --+--. - | ATTR ENTRY[2] --+--+--. - | ... | | | - | ATTR ENTRY[N] --+--+--+--. - | ATTR DATA 0 <-' | | | - | //////////// | | | - | ATTR DATA 1 <----' | | - | ///////////// | | - | ATTR DATA 2 <-------' | - | ///////////// | - | ... | - | ATTR DATA N <----------' - | ///////////// - | Attribute Free Space - | - '----> RESOURCE FORK - ///////////// Variable Sized Data - ///////////// - ///////////// - ///////////// - ///////////// - ///////////// - ... - ///////////// - - ------------------------------------------------------------ - - NOTE: The EXT ATTR HDR, ATTR ENTRY's and ATTR DATA's are - stored as part of the Finder Info. The length in the Finder - Info AppleDouble entry includes the length of the extended - attribute header, attribute entries, and attribute data. -*/ + * Default Implementation (Non-native EA) + */ +/* + * Typical "._" AppleDouble Header File layout: + * ------------------------------------------------------------ + * MAGIC 0x00051607 + * VERSION 0x00020000 + * FILLER 0 + * COUNT 2 + * .-- AD ENTRY[0] Finder Info Entry (must be first) + * .--+-- AD ENTRY[1] Resource Fork Entry (must be last) + * | '-> FINDER INFO + * | ///////////// Fixed Size Data (32 bytes) + * | EXT ATTR HDR + * | ///////////// + * | ATTR ENTRY[0] --. + * | ATTR ENTRY[1] --+--. + * | ATTR ENTRY[2] --+--+--. + * | ... | | | + * | ATTR ENTRY[N] --+--+--+--. + * | ATTR DATA 0 <-' | | | + * | //////////// | | | + * | ATTR DATA 1 <----' | | + * | ///////////// | | + * | ATTR DATA 2 <-------' | + * | ///////////// | + * | ... | + * | ATTR DATA N <----------' + * | ///////////// + * | Attribute Free Space + * | + * '----> RESOURCE FORK + * ///////////// Variable Sized Data + * ///////////// + * ///////////// + * ///////////// + * ///////////// + * ///////////// + * ... + * ///////////// + * + * ------------------------------------------------------------ + * + * NOTE: The EXT ATTR HDR, ATTR ENTRY's and ATTR DATA's are + * stored as part of the Finder Info. The length in the Finder + * Info AppleDouble entry includes the length of the extended + * attribute header, attribute entries, and attribute data. + */ + /* * On Disk Data Structures * @@ -339,7 +1310,7 @@ xattr_protected(const char *attrname) */ #define AD_DATA 1 /* Data fork */ #define AD_RESOURCE 2 /* Resource fork */ -#define AD_REALNAME 3 /* FileÕs name on home file system */ +#define AD_REALNAME 3 /* File's name on home file system */ #define AD_COMMENT 4 /* Standard Mac comment */ #define AD_ICONBW 5 /* Mac black & white icon */ #define AD_ICONCOLOR 6 /* Mac color icon */ @@ -351,7 +1322,7 @@ xattr_protected(const char *attrname) #define AD_MSDOSINFO 12 /* MS-DOS file info, attributes, etc */ #define AD_AFPNAME 13 /* Short name on AFP server */ #define AD_AFPINFO 14 /* AFP file info, attrib., etc */ -#define AD_AFPDIRID 15 /* AFP directory ID */ +#define AD_AFPDIRID 15 /* AFP directory ID */ #define AD_ATTRIBUTES AD_FINDERINFO @@ -361,7 +1332,7 @@ xattr_protected(const char *attrname) #define ATTR_BUF_SIZE 4096 /* default size of the attr file and how much we'll grow by */ /* Implementation Limits */ -#define ATTR_MAX_SIZE (128*1024) /* 128K maximum attribute data size */ +#define ATTR_MAX_SIZE AD_XATTR_MAXSIZE #define ATTR_MAX_HDR_SIZE 65536 /* * Note: ATTR_MAX_HDR_SIZE is the largest attribute header @@ -369,30 +1340,36 @@ xattr_protected(const char *attrname) * the attribute entries must reside within this limit. If * any of the attribute data crosses the ATTR_MAX_HDR_SIZE * boundry, then all of the attribute data I/O is performed - * seperately from the attribute header I/O. + * separately from the attribute header I/O. + * + * In particular, all of the attr_entry structures must lie + * completely within the first ATTR_MAX_HDR_SIZE bytes of the + * AppleDouble file. However, the attribute data (i.e. the + * contents of the extended attributes) may extend beyond the + * first ATTR_MAX_HDR_SIZE bytes of the file. Note that this + * limit is to allow the implementation to optimize by reading + * the first ATTR_MAX_HDR_SIZE bytes of the file. */ -#pragma options align=mac68k - -#define FINDERINFOSIZE 32 +#define FINDERINFOSIZE 32 typedef struct apple_double_entry { - u_int32_t type; /* entry type: see list, 0 invalid */ + u_int32_t type; /* entry type: see list, 0 invalid */ u_int32_t offset; /* entry data offset from the beginning of the file. */ - u_int32_t length; /* entry data length in bytes. */ -} apple_double_entry_t; + u_int32_t length; /* entry data length in bytes. */ +} __attribute__((aligned(2), packed)) apple_double_entry_t; typedef struct apple_double_header { u_int32_t magic; /* == ADH_MAGIC */ - u_int32_t version; /* format version: 2 = 0x00020000 */ + u_int32_t version; /* format version: 2 = 0x00020000 */ u_int32_t filler[4]; - u_int16_t numEntries; /* number of entries which follow */ + u_int16_t numEntries; /* number of entries which follow */ apple_double_entry_t entries[2]; /* 'finfo' & 'rsrc' always exist */ u_int8_t finfo[FINDERINFOSIZE]; /* Must start with Finder Info (32 bytes) */ u_int8_t pad[2]; /* get better alignment inside attr_header */ -} apple_double_header_t; +} __attribute__((aligned(2), packed)) apple_double_header_t; #define ADHDRSIZE (4+4+16+2) @@ -403,21 +1380,21 @@ typedef struct attr_entry { u_int16_t flags; u_int8_t namelen; u_int8_t name[1]; /* NULL-terminated UTF-8 name (up to 128 bytes max) */ -} attr_entry_t; +} __attribute__((aligned(2), packed)) attr_entry_t; -/* Header + entries must fit into 64K */ +/* Header + entries must fit into 64K. Data may extend beyond 64K. */ typedef struct attr_header { apple_double_header_t appledouble; u_int32_t magic; /* == ATTR_HDR_MAGIC */ u_int32_t debug_tag; /* for debugging == file id of owning file */ - u_int32_t total_size; /* total size of attribute header + entries + data */ + u_int32_t total_size; /* file offset of end of attribute header + entries + data */ u_int32_t data_start; /* file offset to attribute data area */ u_int32_t data_length; /* length of attribute data area */ u_int32_t reserved[3]; u_int16_t flags; u_int16_t num_attrs; -} attr_header_t; +} __attribute__((aligned(2), packed)) attr_header_t; /* Empty Resource Fork Header */ @@ -439,14 +1416,12 @@ typedef struct rsrcfork_header { u_int16_t mh_Types; u_int16_t mh_Names; u_int16_t typeCount; -} rsrcfork_header_t; +} __attribute__((aligned(2), packed)) rsrcfork_header_t; #define RF_FIRST_RESOURCE 256 #define RF_NULL_MAP_LENGTH 30 #define RF_EMPTY_TAG "This resource fork intentionally left blank " -#pragma options align=reset - /* Runtime information about the attribute file. */ typedef struct attr_info { vfs_context_t context; @@ -454,7 +1429,7 @@ typedef struct attr_info { size_t filesize; size_t iosize; u_int8_t *rawdata; - size_t rawsize; /* raw size of AppleDouble file */ + size_t rawsize; /* minimum of filesize or ATTR_MAX_HDR_SIZE */ apple_double_header_t *filehdr; apple_double_entry_t *finderinfo; apple_double_entry_t *rsrcfork; @@ -470,7 +1445,7 @@ typedef struct attr_info { #define ATTR_ALIGN 3L /* Use four-byte alignment */ #define ATTR_ENTRY_LENGTH(namelen) \ - ((sizeof(attr_entry_t) - 1 + (namelen) + ATTR_ALIGN) & (~ATTR_ALIGN)) + ((sizeof(attr_entry_t) - 1 + (namelen) + ATTR_ALIGN) & (~ATTR_ALIGN)) #define ATTR_NEXT(ae) \ (attr_entry_t *)((u_int8_t *)(ae) + ATTR_ENTRY_LENGTH((ae)->namelen)) @@ -478,7 +1453,6 @@ typedef struct attr_info { #define ATTR_VALID(ae, ai) \ ((u_int8_t *)ATTR_NEXT(ae) <= ((ai).rawdata + (ai).rawsize)) - #define SWAP16(x) OSSwapBigToHostInt16((x)) #define SWAP32(x) OSSwapBigToHostInt32((x)) #define SWAP64(x) OSSwapBigToHostInt64((x)) @@ -512,25 +1486,120 @@ static int unlock_xattrfile(vnode_t xvp, vfs_context_t context); #if BYTE_ORDER == LITTLE_ENDIAN - static void swap_adhdr(apple_double_header_t *adh); - static void swap_attrhdr(attr_header_t *ah); +static void swap_adhdr(apple_double_header_t *adh); +static void swap_attrhdr(attr_header_t *ah, attr_info_t* info); #else #define swap_adhdr(x) -#define swap_attrhdr(x) +#define swap_attrhdr(x, y) #endif -static int validate_attrhdr(attr_header_t *ah, size_t bufsize); +static int check_and_swap_attrhdr(attr_header_t *ah, attr_info_t* ainfop); static int shift_data_down(vnode_t xvp, off_t start, size_t len, off_t delta, vfs_context_t context); static int shift_data_up(vnode_t xvp, off_t start, size_t len, off_t delta, vfs_context_t context); +/* + * Sanity check and swap the header of an AppleDouble file. Assumes the buffer + * is in big endian (as it would exist on disk). Verifies the following: + * - magic field + * - version field + * - number of entries + * - that each entry fits within the file size + * + * If the header is invalid, ENOATTR is returned. + * + * NOTE: Does not attempt to validate the extended attributes header that + * may be embedded in the Finder Info entry. + */ +static int +check_and_swap_apple_double_header(attr_info_t *ainfop) +{ + int i, j; + u_int32_t header_end; + u_int32_t entry_end; + size_t rawsize; + apple_double_header_t *header; + + rawsize = ainfop->rawsize; + header = (apple_double_header_t *) ainfop->rawdata; + + /* Is the file big enough to contain an AppleDouble header? */ + if (rawsize < offsetof(apple_double_header_t, entries)) { + return ENOATTR; + } + + /* Swap the AppleDouble header fields to native order */ + header->magic = SWAP32(header->magic); + header->version = SWAP32(header->version); + header->numEntries = SWAP16(header->numEntries); + + /* Sanity check the AppleDouble header fields */ + if (header->magic != ADH_MAGIC || + header->version != ADH_VERSION || + header->numEntries < 1 || + header->numEntries > 15) { + return ENOATTR; + } + + /* Calculate where the entries[] array ends */ + header_end = offsetof(apple_double_header_t, entries) + + header->numEntries * sizeof(apple_double_entry_t); + + /* Is the file big enough to contain the AppleDouble entries? */ + if (rawsize < header_end) { + return ENOATTR; + } + + /* Swap and sanity check each AppleDouble entry */ + for (i = 0; i < header->numEntries; i++) { + /* Swap the per-entry fields to native order */ + header->entries[i].type = SWAP32(header->entries[i].type); + header->entries[i].offset = SWAP32(header->entries[i].offset); + header->entries[i].length = SWAP32(header->entries[i].length); + + entry_end = header->entries[i].offset + header->entries[i].length; + + /* + * Does the entry's content start within the header itself, + * did the addition overflow, or does the entry's content + * extend past the end of the file? + */ + if (header->entries[i].offset < header_end || + entry_end < header->entries[i].offset || + entry_end > ainfop->filesize) { + return ENOATTR; + } + + /* + * Does the current entry's content overlap with a previous + * entry's content? + * + * Yes, this is O(N**2), and there are more efficient algorithms + * for testing pairwise overlap of N ranges when N is large. + * But we have already ensured N < 16, and N is almost always 2. + * So there's no point in using a more complex algorithm. + */ + + for (j = 0; j < i; j++) { + if (entry_end > header->entries[j].offset && + header->entries[j].offset + header->entries[j].length > header->entries[i].offset) { + return ENOATTR; + } + } + } + + return 0; +} + + + /* * Retrieve the data of an extended attribute. */ static int default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, - __unused int options, vfs_context_t context) + __unused int options, vfs_context_t context) { vnode_t xvp = NULL; attr_info_t ainfo; @@ -545,7 +1614,7 @@ default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, int error; fileflags = FREAD; - if (bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) == 0) { + if (strcmp(name, XATTR_RESOURCEFORK_NAME) == 0) { isrsrcfork = 1; /* * Open the file locked (shared) since the Carbon @@ -558,16 +1627,15 @@ default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, } if ((error = open_xattrfile(vp, fileflags, &xvp, context))) { - return (error); + return error; } if ((error = get_xattrinfo(xvp, 0, &ainfo, context))) { close_xattrfile(xvp, fileflags, context); - return (error); + return error; } /* Get the Finder Info. */ - if (bcmp(name, XATTR_FINDERINFO_NAME, sizeof(XATTR_FINDERINFO_NAME)) == 0) { - + if (strcmp(name, XATTR_FINDERINFO_NAME) == 0) { if (ainfo.finderinfo == NULL || ainfo.emptyfinderinfo) { error = ENOATTR; } else if (uio == NULL) { @@ -595,12 +1663,13 @@ default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, } else { uio_setoffset(uio, uio_offset(uio) + ainfo.rsrcfork->offset); error = VNOP_READ(xvp, uio, 0, context); - if (error == 0) + if (error == 0) { uio_setoffset(uio, uio_offset(uio) - ainfo.rsrcfork->offset); + } } goto out; } - + if (ainfo.attrhdr == NULL || ainfo.attr_entry == NULL) { error = ENOATTR; goto out; @@ -617,14 +1686,14 @@ default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, * Search for attribute name in the header. */ for (i = 0; i < header->num_attrs && ATTR_VALID(entry, ainfo); i++) { - if (strncmp(entry->name, name, namelen) == 0) { + if (strncmp((const char *)entry->name, name, namelen) == 0) { datalen = (size_t)entry->length; if (uio == NULL) { *size = datalen; error = 0; break; } - if (uio_resid(uio) < datalen) { + if (uio_resid(uio) < (user_ssize_t)datalen) { error = ERANGE; break; } @@ -640,11 +1709,11 @@ default_getxattr(vnode_t vp, const char *name, uio_t uio, size_t *size, } entry = ATTR_NEXT(entry); } -out: +out: rel_xattrinfo(&ainfo); close_xattrfile(xvp, fileflags, context); - return (error); + return error; } /* @@ -668,14 +1737,49 @@ default_setxattr(vnode_t vp, const char *name, uio_t uio, int options, vfs_conte int splitdata; int fileflags; int error; + char finfo[FINDERINFOSIZE]; datalen = uio_resid(uio); namelen = strlen(name) + 1; entrylen = ATTR_ENTRY_LENGTH(namelen); - if (datalen > ATTR_MAX_SIZE) { - return (E2BIG); /* EINVAL instead ? */ + /* + * By convention, Finder Info that is all zeroes is equivalent to not + * having a Finder Info EA. So if we're trying to set the Finder Info + * to all zeroes, then delete it instead. If a file didn't have an + * AppleDouble file before, this prevents creating an AppleDouble file + * with no useful content. + * + * If neither XATTR_CREATE nor XATTR_REPLACE were specified, we check + * for all zeroes Finder Info before opening the AppleDouble file. + * But if either of those options were specified, we need to open the + * AppleDouble file to see whether there was already Finder Info (so we + * can return an error if needed); this case is handled further below. + * + * NOTE: this copies the Finder Info data into the "finfo" local. + */ + if (bcmp(name, XATTR_FINDERINFO_NAME, sizeof(XATTR_FINDERINFO_NAME)) == 0) { + /* + * TODO: check the XATTR_CREATE and XATTR_REPLACE flags. + * That means we probably have to open_xattrfile and get_xattrinfo. + */ + if (uio_offset(uio) != 0 || datalen != FINDERINFOSIZE) { + return EINVAL; + } + error = uiomove(finfo, datalen, uio); + if (error) { + return error; + } + if ((options & (XATTR_CREATE | XATTR_REPLACE)) == 0 && + bcmp(finfo, emptyfinfo, FINDERINFOSIZE) == 0) { + error = default_removexattr(vp, name, 0, context); + if (error == ENOATTR) { + error = 0; + } + return error; + } } + start: /* * Open the file locked since setting an attribute @@ -683,11 +1787,11 @@ start: */ fileflags = FREAD | FWRITE | O_EXLOCK; if ((error = open_xattrfile(vp, O_CREAT | fileflags, &xvp, context))) { - return (error); + return error; } if ((error = get_xattrinfo(xvp, ATTR_SETTING, &ainfo, context))) { close_xattrfile(xvp, fileflags, context); - return (error); + return error; } /* Set the Finder Info. */ @@ -705,15 +1809,30 @@ start: goto out; } } - if (uio_offset(uio) != 0 || datalen != FINDERINFOSIZE) { - error = EINVAL; - goto out; + if (options != 0 && bcmp(finfo, emptyfinfo, FINDERINFOSIZE) == 0) { + /* + * Setting the Finder Info to all zeroes is equivalent to + * removing it. Close the xattr file and let + * default_removexattr do the work (including deleting + * the xattr file if there are no other xattrs). + * + * Note that we have to handle the case where the + * Finder Info was already all zeroes, and we ignore + * ENOATTR. + * + * The common case where options == 0 was handled above. + */ + rel_xattrinfo(&ainfo); + close_xattrfile(xvp, fileflags, context); + error = default_removexattr(vp, name, 0, context); + if (error == ENOATTR) { + error = 0; + } + return error; } if (ainfo.finderinfo) { attrdata = (u_int8_t *)ainfo.filehdr + ainfo.finderinfo->offset; - error = uiomove((caddr_t)attrdata, datalen, uio); - if (error) - goto out; + bcopy(finfo, attrdata, datalen); ainfo.iosize = sizeof(attr_header_t); error = write_xattrinfo(&ainfo); goto out; @@ -730,24 +1849,38 @@ start: error = EPERM; goto out; } - if (ainfo.rsrcfork && ainfo.rsrcfork->length) { - /* attr exists and "create" was specified? */ - if (options & XATTR_CREATE) { - error = EEXIST; - goto out; + /* Make sure we have a rsrc fork pointer.. */ + if (ainfo.rsrcfork == NULL) { + error = ENOATTR; + goto out; + } + if (ainfo.rsrcfork) { + if (ainfo.rsrcfork->length != 0) { + if (options & XATTR_CREATE) { + /* attr exists, and create specified ? */ + error = EEXIST; + goto out; + } + } else { + /* Zero length AD rsrc fork */ + if (options & XATTR_REPLACE) { + /* attr doesn't exist (0-length), but replace specified ? */ + error = ENOATTR; + goto out; + } } } else { - /* attr doesn't exists and "replace" was specified? */ - if (options & XATTR_REPLACE) { - error = ENOATTR; - goto out; - } + /* We can't do much if we somehow didn't get an AD rsrc pointer */ + error = ENOATTR; + goto out; } + endoffset = uio_resid(uio) + uio_offset(uio); /* new size */ uio_setoffset(uio, uio_offset(uio) + ainfo.rsrcfork->offset); error = VNOP_WRITE(xvp, uio, 0, context); - if (error) + if (error) { goto out; + } uio_setoffset(uio, uio_offset(uio) - ainfo.rsrcfork->offset); if (endoffset > ainfo.rsrcfork->length) { ainfo.rsrcfork->length = endoffset; @@ -758,6 +1891,10 @@ start: goto out; } + if (datalen > ATTR_MAX_SIZE) { + return E2BIG; /* EINVAL instead ? */ + } + if (ainfo.attrhdr == NULL) { error = ENOATTR; goto out; @@ -766,16 +1903,17 @@ start: entry = ainfo.attr_entry; /* Check if data area crosses the maximum header size. */ - if ((header->data_start + header->data_length + entrylen + datalen) > ATTR_MAX_HDR_SIZE) + if ((header->data_start + header->data_length + entrylen + datalen) > ATTR_MAX_HDR_SIZE) { splitdata = 1; /* do data I/O separately */ - else + } else { splitdata = 0; - + } + /* * See if attribute already exists. */ for (i = 0; i < header->num_attrs && ATTR_VALID(entry, ainfo); i++) { - if (strncmp(entry->name, name, namelen) == 0) { + if (strncmp((const char *)entry->name, name, namelen) == 0) { found = 1; break; } @@ -798,8 +1936,9 @@ start: } else { attrdata = (u_int8_t *)header + entry->offset; error = uiomove((caddr_t)attrdata, datalen, uio); - if (error) + if (error) { goto out; + } ainfo.iosize = ainfo.attrhdr->data_start + ainfo.attrhdr->data_length; error = write_xattrinfo(&ainfo); if (error) { @@ -816,11 +1955,12 @@ start: close_xattrfile(xvp, fileflags, context); error = default_removexattr(vp, name, options, context); if (error) { - goto out; + return error; } + /* Clear XATTR_REPLACE option since we just removed the attribute. */ + options &= ~XATTR_REPLACE; goto start; /* start over */ } - } if (options & XATTR_REPLACE) { @@ -840,7 +1980,7 @@ start: size_t growsize; growsize = roundup((datalen + entrylen) - datafreespace, ATTR_BUF_SIZE); - + /* Clip roundup size when we can still fit in ATTR_MAX_HDR_SIZE. */ if (!splitdata && (header->total_size + growsize) > ATTR_MAX_HDR_SIZE) { growsize = ATTR_MAX_HDR_SIZE - header->total_size; @@ -851,8 +1991,9 @@ start: if (error) { printf("setxattr: VNOP_TRUNCATE error %d\n", error); } - if (error) + if (error) { goto out; + } /* * Move the resource fork out of the way. @@ -860,9 +2001,9 @@ start: if (ainfo.rsrcfork) { if (ainfo.rsrcfork->length != 0) { shift_data_down(xvp, - ainfo.rsrcfork->offset, - ainfo.rsrcfork->length, - growsize, context); + ainfo.rsrcfork->offset, + ainfo.rsrcfork->length, + growsize, context); } ainfo.rsrcfork->offset += growsize; } @@ -873,13 +2014,13 @@ start: /* Make space for a new entry. */ if (splitdata) { shift_data_down(xvp, - header->data_start, - header->data_length, - entrylen, context); + header->data_start, + header->data_length, + entrylen, context); } else { bcopy((u_int8_t *)header + header->data_start, - (u_int8_t *)header + header->data_start + entrylen, - header->data_length); + (u_int8_t *)header + header->data_start + entrylen, + header->data_length); } header->data_start += entrylen; @@ -888,7 +2029,7 @@ start: for (entry = ainfo.attr_entry; entry != lastentry && ATTR_VALID(entry, ainfo); entry = ATTR_NEXT(entry)) { entry->offset += entrylen; } - + /* * If the attribute data area is entirely within * the header buffer, then just update the buffer, @@ -908,7 +2049,7 @@ start: } } else { attrdata = (u_int8_t *)header + header->data_start + header->data_length; - + error = uiomove((caddr_t)attrdata, datalen, uio); if (error) { printf("setxattr: uiomove error %d\n", error); @@ -931,7 +2072,7 @@ start: /* Only write the entries, since the data was written separately. */ ainfo.iosize = ainfo.attrhdr->data_start; } else { - /* The entry and data are both in the header; write them together. */ + /* The entry and data are both in the header; write them together. */ ainfo.iosize = ainfo.attrhdr->data_start + ainfo.attrhdr->data_length; } error = write_xattrinfo(&ainfo); @@ -939,7 +2080,7 @@ start: printf("setxattr: write_xattrinfo error %d\n", error); } -out: +out: rel_xattrinfo(&ainfo); close_xattrfile(xvp, fileflags, context); @@ -956,7 +2097,10 @@ out: (void) vnode_setattr(vp, &va, context); } } - return (error); + + post_event_if_success(vp, error, NOTE_ATTRIB); + + return error; } @@ -985,7 +2129,7 @@ default_removexattr(vnode_t vp, const char *name, __unused int options, vfs_cont int error; fileflags = FREAD | FWRITE; - if (bcmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) == 0) { + if (strncmp(name, XATTR_RESOURCEFORK_NAME, sizeof(XATTR_RESOURCEFORK_NAME)) == 0) { isrsrcfork = 1; /* * Open the file locked (exclusive) since the Carbon @@ -998,28 +2142,32 @@ default_removexattr(vnode_t vp, const char *name, __unused int options, vfs_cont } if ((error = open_xattrfile(vp, fileflags, &xvp, context))) { - return (error); + return error; } if ((error = get_xattrinfo(xvp, 0, &ainfo, context))) { close_xattrfile(xvp, fileflags, context); - return (error); + return error; } - if (ainfo.attrhdr) + if (ainfo.attrhdr) { attrcount += ainfo.attrhdr->num_attrs; - if (ainfo.rsrcfork) + } + if (ainfo.rsrcfork) { ++attrcount; - if (ainfo.finderinfo && !ainfo.emptyfinderinfo) + } + if (ainfo.finderinfo && !ainfo.emptyfinderinfo) { ++attrcount; + } /* Clear the Finder Info. */ - if (bcmp(name, XATTR_FINDERINFO_NAME, sizeof(XATTR_FINDERINFO_NAME)) == 0) { + if (strncmp(name, XATTR_FINDERINFO_NAME, sizeof(XATTR_FINDERINFO_NAME)) == 0) { if (ainfo.finderinfo == NULL || ainfo.emptyfinderinfo) { error = ENOATTR; goto out; } /* On removal of last attribute the ._ file is removed. */ - if (--attrcount == 0) + if (--attrcount == 0) { goto out; + } attrdata = (u_int8_t *)ainfo.filehdr + ainfo.finderinfo->offset; bzero((caddr_t)attrdata, FINDERINFOSIZE); ainfo.iosize = sizeof(attr_header_t); @@ -1038,8 +2186,9 @@ default_removexattr(vnode_t vp, const char *name, __unused int options, vfs_cont goto out; } /* On removal of last attribute the ._ file is removed. */ - if (--attrcount == 0) + if (--attrcount == 0) { goto out; + } /* * XXX * If the resource fork isn't the last AppleDouble @@ -1070,10 +2219,11 @@ default_removexattr(vnode_t vp, const char *name, __unused int options, vfs_cont * See if this attribute exists. */ for (i = 0; i < header->num_attrs && ATTR_VALID(entry, ainfo); i++) { - if (strncmp(entry->name, name, namelen) == 0) { + if (strncmp((const char *)entry->name, name, namelen) == 0) { found = 1; - if ((i+1) == header->num_attrs) + if ((i + 1) == header->num_attrs) { lastone = 1; + } break; } entry = ATTR_NEXT(entry); @@ -1083,51 +2233,51 @@ default_removexattr(vnode_t vp, const char *name, __unused int options, vfs_cont goto out; } /* On removal of last attribute the ._ file is removed. */ - if (--attrcount == 0) + if (--attrcount == 0) { goto out; + } datalen = entry->length; dataoff = entry->offset; entrylen = ATTR_ENTRY_LENGTH(namelen); - if ((header->data_start + header->data_length) > ATTR_MAX_HDR_SIZE) + if ((header->data_start + header->data_length) > ATTR_MAX_HDR_SIZE) { splitdata = 1; - else + } else { splitdata = 0; + } /* Remove the attribute entry. */ if (!lastone) { bcopy((u_int8_t *)entry + entrylen, (u_int8_t *)entry, - ((size_t)header + header->data_start) - ((size_t)entry + entrylen)); + ((size_t)header + header->data_start) - ((size_t)entry + entrylen)); } /* Adjust the attribute data. */ if (splitdata) { shift_data_up(xvp, - header->data_start, - dataoff - header->data_start, - entrylen, - context); + header->data_start, + dataoff - header->data_start, + entrylen, + context); if (!lastone) { shift_data_up(xvp, - dataoff + datalen, - (header->data_start + header->data_length) - (dataoff + datalen), - datalen + entrylen, - context); + dataoff + datalen, + (header->data_start + header->data_length) - (dataoff + datalen), + datalen + entrylen, + context); } /* XXX write zeros to freed space ? */ ainfo.iosize = ainfo.attrhdr->data_start - entrylen; } else { - - bcopy((u_int8_t *)header + header->data_start, - (u_int8_t *)header + header->data_start - entrylen, - dataoff - header->data_start); + (u_int8_t *)header + header->data_start - entrylen, + dataoff - header->data_start); if (!lastone) { bcopy((u_int8_t *)header + dataoff + datalen, - (u_int8_t *)header + dataoff - entrylen, - (header->data_start + header->data_length) - (dataoff + datalen)); + (u_int8_t *)header + dataoff - entrylen, + (header->data_start + header->data_length) - (dataoff + datalen)); } - bzero (((u_int8_t *)header + header->data_start + header->data_length) - (datalen + entrylen), (datalen + entrylen)); + bzero(((u_int8_t *)header + header->data_start + header->data_length) - (datalen + entrylen), (datalen + entrylen)); ainfo.iosize = ainfo.attrhdr->data_start + ainfo.attrhdr->data_length; } @@ -1140,8 +2290,9 @@ default_removexattr(vnode_t vp, const char *name, __unused int options, vfs_cont entry = ainfo.attr_entry; for (i = 0; i < header->num_attrs && ATTR_VALID(entry, ainfo); i++) { entry->offset -= entrylen; - if (entry >= oldslot) + if (entry >= oldslot) { entry->offset -= datalen; + } entry = ATTR_NEXT(entry); } error = write_xattrinfo(&ainfo); @@ -1153,8 +2304,9 @@ out: /* When there are no more attributes remove the ._ file. */ if (attrcount == 0) { - if (fileflags & O_EXLOCK) + if (fileflags & O_EXLOCK) { (void) unlock_xattrfile(xvp, context); + } VNOP_CLOSE(xvp, fileflags, context); vnode_rele(xvp); error = remove_xattrfile(xvp, context); @@ -1175,8 +2327,10 @@ out: (void) vnode_setattr(vp, &va, context); } } - return (error); - + + post_event_if_success(vp, error, NOTE_ATTRIB); + + return error; } @@ -1199,25 +2353,29 @@ default_listxattr(vnode_t vp, uio_t uio, size_t *size, __unused int options, vfs */ if ((error = open_xattrfile(vp, FREAD, &xvp, context))) { - if (error == ENOATTR) + if (error == ENOATTR) { error = 0; - return (error); + } + return error; } if ((error = get_xattrinfo(xvp, 0, &ainfo, context))) { + if (error == ENOATTR) { + error = 0; + } close_xattrfile(xvp, FREAD, context); - return (error); + return error; } /* Check for Finder Info. */ if (ainfo.finderinfo && !ainfo.emptyfinderinfo) { if (uio == NULL) { *size += sizeof(XATTR_FINDERINFO_NAME); - } else if (uio_resid(uio) < sizeof(XATTR_FINDERINFO_NAME)) { + } else if (uio_resid(uio) < (user_ssize_t)sizeof(XATTR_FINDERINFO_NAME)) { error = ERANGE; goto out; } else { - error = uiomove((caddr_t)XATTR_FINDERINFO_NAME, - sizeof(XATTR_FINDERINFO_NAME), uio); + error = uiomove(XATTR_FINDERINFO_NAME, + sizeof(XATTR_FINDERINFO_NAME), uio); if (error) { error = ERANGE; goto out; @@ -1229,12 +2387,12 @@ default_listxattr(vnode_t vp, uio_t uio, size_t *size, __unused int options, vfs if (vnode_isreg(vp) && ainfo.rsrcfork) { if (uio == NULL) { *size += sizeof(XATTR_RESOURCEFORK_NAME); - } else if (uio_resid(uio) < sizeof(XATTR_RESOURCEFORK_NAME)) { + } else if (uio_resid(uio) < (user_ssize_t)sizeof(XATTR_RESOURCEFORK_NAME)) { error = ERANGE; goto out; } else { - error = uiomove((caddr_t)XATTR_RESOURCEFORK_NAME, - sizeof(XATTR_RESOURCEFORK_NAME), uio); + error = uiomove(XATTR_RESOURCEFORK_NAME, + sizeof(XATTR_RESOURCEFORK_NAME), uio); if (error) { error = ERANGE; goto out; @@ -1246,8 +2404,10 @@ default_listxattr(vnode_t vp, uio_t uio, size_t *size, __unused int options, vfs if (ainfo.attrhdr) { count = ainfo.attrhdr->num_attrs; for (i = 0, entry = ainfo.attr_entry; i < count && ATTR_VALID(entry, ainfo); i++) { - if (xattr_protected(entry->name) || - xattr_validatename(entry->name) != 0) { + if (xattr_protected((const char *)entry->name) || + ((entry->namelen < XATTR_MAXNAMELEN) && + (entry->name[entry->namelen] == '\0') && + (xattr_validatename((const char *)entry->name) != 0))) { entry = ATTR_NEXT(entry); continue; } @@ -1262,18 +2422,19 @@ default_listxattr(vnode_t vp, uio_t uio, size_t *size, __unused int options, vfs } error = uiomove((caddr_t) entry->name, entry->namelen, uio); if (error) { - if (error != EFAULT) + if (error != EFAULT) { error = ERANGE; + } break; - } + } entry = ATTR_NEXT(entry); } } -out: +out: rel_xattrinfo(&ainfo); close_xattrfile(xvp, FREAD, context); - return (error); + return error; } static int @@ -1285,7 +2446,7 @@ open_xattrfile(vnode_t vp, int fileflags, vnode_t *xvpp, vfs_context_t context) struct nameidata nd; char smallname[64]; char *filename = NULL; - char *basename = NULL; + const char *basename = NULL; size_t len; errno_t error; int opened = 0; @@ -1296,15 +2457,15 @@ open_xattrfile(vnode_t vp, int fileflags, vnode_t *xvpp, vfs_context_t context) * For the root directory use "._." to hold the attributes. */ filename = &smallname[0]; - sprintf(filename, "%s%s", ATTR_FILE_PREFIX, "."); + snprintf(filename, sizeof(smallname), "%s%s", ATTR_FILE_PREFIX, "."); dvp = vp; /* the "._." file resides in the root dir */ goto lookup; } - if ( (dvp = vnode_getparent(vp)) == NULLVP) { + if ((dvp = vnode_getparent(vp)) == NULLVP) { error = ENOATTR; goto out; } - if ( (basename = vnode_getname(vp)) == NULL) { + if ((basename = vnode_getname(vp)) == NULL) { error = ENOATTR; goto out; } @@ -1331,25 +2492,28 @@ open_xattrfile(vnode_t vp, int fileflags, vnode_t *xvpp, vfs_context_t context) * file security from the EA must always get access */ lookup: - NDINIT(&nd, LOOKUP, LOCKLEAF | NOFOLLOW | USEDVP | DONOTAUTH, UIO_SYSSPACE, - CAST_USER_ADDR_T(filename), context); - nd.ni_dvp = dvp; + NDINIT(&nd, LOOKUP, OP_OPEN, LOCKLEAF | NOFOLLOW | USEDVP | DONOTAUTH, + UIO_SYSSPACE, CAST_USER_ADDR_T(filename), context); + nd.ni_dvp = dvp; if (fileflags & O_CREAT) { nd.ni_cnd.cn_nameiop = CREATE; +#if CONFIG_TRIGGERS + nd.ni_op = OP_LINK; +#endif if (dvp != vp) { nd.ni_cnd.cn_flags |= LOCKPARENT; } - if ( (error = namei(&nd))) { - nd.ni_dvp = NULLVP; + if ((error = namei(&nd))) { + nd.ni_dvp = NULLVP; error = ENOATTR; goto out; } - if ( (xvp = nd.ni_vp) == NULLVP) { + if ((xvp = nd.ni_vp) == NULLVP) { uid_t uid; gid_t gid; mode_t umode; - + /* * Pick up uid/gid/mode from target file. */ @@ -1357,46 +2521,53 @@ lookup: VATTR_WANTED(&va, va_uid); VATTR_WANTED(&va, va_gid); VATTR_WANTED(&va, va_mode); - if (VNOP_GETATTR(vp, &va, context) == 0 && - VATTR_IS_SUPPORTED(&va, va_uid) && - VATTR_IS_SUPPORTED(&va, va_gid) && + if (VNOP_GETATTR(vp, &va, context) == 0 && + VATTR_IS_SUPPORTED(&va, va_uid) && + VATTR_IS_SUPPORTED(&va, va_gid) && VATTR_IS_SUPPORTED(&va, va_mode)) { uid = va.va_uid; gid = va.va_gid; - umode = va.va_mode & (S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH); - } else /* fallback values */ { + umode = va.va_mode & (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); + } else { /* fallback values */ uid = KAUTH_UID_NONE; gid = KAUTH_GID_NONE; - umode = S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH; + umode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH; } VATTR_INIT(&va); VATTR_SET(&va, va_type, VREG); VATTR_SET(&va, va_mode, umode); - if (uid != KAUTH_UID_NONE) + if (uid != KAUTH_UID_NONE) { VATTR_SET(&va, va_uid, uid); - if (gid != KAUTH_GID_NONE) + } + if (gid != KAUTH_GID_NONE) { VATTR_SET(&va, va_gid, gid); + } - error = vn_create(dvp, &nd.ni_vp, &nd.ni_cnd, &va, - VN_CREATE_NOAUTH | VN_CREATE_NOINHERIT, - context); - if (error == 0) - xvp = nd.ni_vp; + error = vn_create(dvp, &nd.ni_vp, &nd, &va, + VN_CREATE_NOAUTH | VN_CREATE_NOINHERIT | VN_CREATE_NOLABEL, + 0, NULL, + context); + if (error) { + error = ENOATTR; + } else { + xvp = nd.ni_vp; + } } nameidone(&nd); if (dvp != vp) { vnode_put(dvp); /* drop iocount from LOCKPARENT request above */ } - if (error) - goto out; + if (error) { + goto out; + } } else { - if ((error = namei(&nd))) { - nd.ni_dvp = NULLVP; + if ((error = namei(&nd))) { + nd.ni_dvp = NULLVP; error = ENOATTR; - goto out; + goto out; } - xvp = nd.ni_vp; + xvp = nd.ni_vp; nameidone(&nd); } nd.ni_dvp = NULLVP; @@ -1420,8 +2591,8 @@ lookup: goto out; } } - - if ( (error = VNOP_OPEN(xvp, fileflags, context))) { + + if ((error = VNOP_OPEN(xvp, fileflags & ~(O_EXLOCK | O_SHLOCK), context))) { error = ENOATTR; goto out; } @@ -1438,11 +2609,11 @@ lookup: VATTR_WANTED(&va, va_data_size); VATTR_WANTED(&va, va_fileid); VATTR_WANTED(&va, va_nlink); - if ( (error = vnode_getattr(xvp, &va, context)) != 0) { + if ((error = vnode_getattr(xvp, &va, context)) != 0) { error = EPERM; goto out; } - + /* If the file is empty then add a default header. */ if (va.va_data_size == 0) { /* Don't adopt hard-linked "._" files. */ @@ -1450,32 +2621,33 @@ lookup: error = EPERM; goto out; } - if ( (error = create_xattrfile(xvp, (u_int32_t)va.va_fileid, context))) + if ((error = create_xattrfile(xvp, (u_int32_t)va.va_fileid, context))) { goto out; + } } } - /* Apply file locking if requested. */ + /* Apply file locking if requested. */ if (fileflags & (O_EXLOCK | O_SHLOCK)) { short locktype; locktype = (fileflags & O_EXLOCK) ? F_WRLCK : F_RDLCK; error = lock_xattrfile(xvp, locktype, context); + if (error) { + error = ENOATTR; + } } out: - if (dvp && (dvp != vp)) { - vnode_put(dvp); - } - if (basename) { - vnode_putname(basename); - } - if (filename && filename != &smallname[0]) { - FREE(filename, M_TEMP); - } if (error) { if (xvp != NULLVP) { if (opened) { (void) VNOP_CLOSE(xvp, fileflags, context); } + + if (fileflags & O_CREAT) { + /* Delete the xattr file if we encountered any errors */ + (void) remove_xattrfile(xvp, context); + } + if (referenced) { (void) vnode_rele(xvp); } @@ -1486,8 +2658,19 @@ out: error = EPERM; } } + /* Release resources after error-handling */ + if (dvp && (dvp != vp)) { + vnode_put(dvp); + } + if (basename) { + vnode_putname(basename); + } + if (filename && filename != &smallname[0]) { + FREE(filename, M_TEMP); + } + *xvpp = xvp; /* return a referenced vnode */ - return (error); + return error; } static void @@ -1496,8 +2679,9 @@ close_xattrfile(vnode_t xvp, int fileflags, vfs_context_t context) // if (fileflags & FWRITE) // (void) VNOP_FSYNC(xvp, MNT_WAIT, context); - if (fileflags & (O_EXLOCK | O_SHLOCK)) + if (fileflags & (O_EXLOCK | O_SHLOCK)) { (void) unlock_xattrfile(xvp, context); + } (void) VNOP_CLOSE(xvp, fileflags, context); (void) vnode_rele(xvp); @@ -1509,20 +2693,28 @@ remove_xattrfile(vnode_t xvp, vfs_context_t context) { vnode_t dvp; struct nameidata nd; - char *path; + char *path = NULL; int pathlen; int error = 0; - path = get_pathbuff(); + MALLOC_ZONE(path, char *, MAXPATHLEN, M_NAMEI, M_WAITOK); + if (path == NULL) { + return ENOMEM; + } + pathlen = MAXPATHLEN; - vn_getpath(xvp, path, &pathlen); + error = vn_getpath(xvp, path, &pathlen); + if (error) { + FREE_ZONE(path, MAXPATHLEN, M_NAMEI); + return error; + } - NDINIT(&nd, DELETE, LOCKPARENT | NOFOLLOW | DONOTAUTH, - UIO_SYSSPACE, CAST_USER_ADDR_T(path), context); + NDINIT(&nd, DELETE, OP_UNLINK, LOCKPARENT | NOFOLLOW | DONOTAUTH, + UIO_SYSSPACE, CAST_USER_ADDR_T(path), context); error = namei(&nd); - release_pathbuff(path); + FREE_ZONE(path, MAXPATHLEN, M_NAMEI); if (error) { - return (error); + return error; } dvp = nd.ni_dvp; xvp = nd.ni_vp; @@ -1532,16 +2724,34 @@ remove_xattrfile(vnode_t xvp, vfs_context_t context) vnode_put(dvp); vnode_put(xvp); - return (error); + return error; } +/* + * Read in and parse the AppleDouble header and entries, and the extended + * attribute header and entries if any. Populates the fields of ainfop + * based on the headers and entries found. + * + * The basic idea is to: + * - Read in up to ATTR_MAX_HDR_SIZE bytes of the start of the file. All + * AppleDouble entries, the extended attribute header, and extended + * attribute entries must lie within this part of the file; the rest of + * the AppleDouble handling code assumes this. Plus it allows us to + * somewhat optimize by doing a smaller number of larger I/Os. + * - Swap and sanity check the AppleDouble header (including the AppleDouble + * entries). + * - Find the Finder Info and Resource Fork entries, if any. + * - If we're going to be writing, try to make sure the Finder Info entry has + * room to store the extended attribute header, plus some space for extended + * attributes. + * - Swap and sanity check the extended attribute header and entries (if any). + */ static int get_xattrinfo(vnode_t xvp, int setting, attr_info_t *ainfop, vfs_context_t context) { uio_t auio = NULL; void * buffer = NULL; apple_double_header_t *filehdr; - attr_header_t *attrhdr; struct vnode_attr va; size_t iosize; int i; @@ -1559,10 +2769,11 @@ get_xattrinfo(vnode_t xvp, int setting, attr_info_t *ainfop, vfs_context_t conte ainfop->filesize = va.va_data_size; /* When setting attributes, allow room for the header to grow. */ - if (setting) + if (setting) { iosize = ATTR_MAX_HDR_SIZE; - else + } else { iosize = MIN(ATTR_MAX_HDR_SIZE, ainfop->filesize); + } if (iosize == 0) { error = ENOATTR; @@ -1570,7 +2781,12 @@ get_xattrinfo(vnode_t xvp, int setting, attr_info_t *ainfop, vfs_context_t conte } ainfop->iosize = iosize; MALLOC(buffer, void *, iosize, M_TEMP, M_WAITOK); - auio = uio_create(1, 0, UIO_SYSSPACE32, UIO_READ); + if (buffer == NULL) { + error = ENOMEM; + goto bail; + } + + auio = uio_create(1, 0, UIO_SYSSPACE, UIO_READ); uio_addiov(auio, (uintptr_t)buffer, iosize); /* Read the file header. */ @@ -1580,114 +2796,76 @@ get_xattrinfo(vnode_t xvp, int setting, attr_info_t *ainfop, vfs_context_t conte } ainfop->rawsize = iosize - uio_resid(auio); ainfop->rawdata = (u_int8_t *)buffer; - + filehdr = (apple_double_header_t *)buffer; - /* Check for Apple Double file. */ - if (SWAP32(filehdr->magic) != ADH_MAGIC || - SWAP32(filehdr->version) != ADH_VERSION || - SWAP16(filehdr->numEntries) < 1 || - SWAP16(filehdr->numEntries) > 15) { - error = ENOATTR; - goto bail; - } - if (ADHDRSIZE + (SWAP16(filehdr->numEntries) * sizeof(apple_double_entry_t)) > ainfop->rawsize) { - error = EINVAL; + error = check_and_swap_apple_double_header(ainfop); + if (error) { goto bail; } - swap_adhdr(filehdr); ainfop->filehdr = filehdr; /* valid AppleDouble header */ + /* rel_xattrinfo is responsible for freeing the header buffer */ buffer = NULL; - /* Check the AppleDouble entries. */ + /* Find the Finder Info and Resource Fork entries, if any */ for (i = 0; i < filehdr->numEntries; ++i) { if (filehdr->entries[i].type == AD_FINDERINFO && - filehdr->entries[i].length > 0) { + filehdr->entries[i].length >= FINDERINFOSIZE) { + /* We found the Finder Info entry. */ ainfop->finderinfo = &filehdr->entries[i]; - attrhdr = (attr_header_t *)filehdr; - if (bcmp((u_int8_t*)ainfop->filehdr + ainfop->finderinfo->offset, - emptyfinfo, sizeof(emptyfinfo)) == 0) { + /* + * Is the Finder Info "empty" (all zeroes)? If so, + * we'll pretend like the Finder Info extended attribute + * does not exist. + * + * Note: we have to make sure the Finder Info is + * contained within the buffer we have already read, + * to avoid accidentally accessing a bogus address. + * If it is outside the buffer, we just assume the + * Finder Info is non-empty. + */ + if (ainfop->finderinfo->offset + FINDERINFOSIZE <= ainfop->rawsize && + bcmp((u_int8_t*)ainfop->filehdr + ainfop->finderinfo->offset, emptyfinfo, sizeof(emptyfinfo)) == 0) { ainfop->emptyfinderinfo = 1; } - - if (i != 0) { + } + if (filehdr->entries[i].type == AD_RESOURCE) { + /* + * Ignore zero-length resource forks when getting. If setting, + * we need to remember the resource fork entry so it can be + * updated once the new content has been written. + */ + if (filehdr->entries[i].length == 0 && !setting) { continue; } - /* See if we need to convert this AppleDouble file. */ - if (filehdr->entries[0].length == FINDERINFOSIZE) { - size_t delta; - size_t writesize; - - if (!setting || - filehdr->entries[1].type != AD_RESOURCE || - filehdr->numEntries > 2) { - continue; /* not expected layout */ - } - delta = ATTR_BUF_SIZE - (filehdr->entries[0].offset + FINDERINFOSIZE); - if (filehdr->entries[1].length) { - /* Make some room. */ - shift_data_down(xvp, - filehdr->entries[1].offset, - filehdr->entries[1].length, - delta, context); - writesize = sizeof(attr_header_t); - } else { - rsrcfork_header_t *rsrcforkhdr; - - vnode_setsize(xvp, filehdr->entries[1].offset + delta, 0, context); - - /* Steal some space for an empty RF header. */ - delta -= sizeof(rsrcfork_header_t); - - bzero(&attrhdr->appledouble.pad[0], delta); - rsrcforkhdr = (rsrcfork_header_t *)((char *)filehdr + filehdr->entries[1].offset + delta); - - /* Fill in Empty Resource Fork Header. */ - init_empty_resource_fork(rsrcforkhdr); - - filehdr->entries[1].length = sizeof(rsrcfork_header_t); - writesize = ATTR_BUF_SIZE; + + /* + * Check to see if any "empty" resource fork is ours (i.e. is ignorable). + * + * The "empty" resource headers we created have a system data tag of: + * "This resource fork intentionally left blank " + */ + if (filehdr->entries[i].length == sizeof(rsrcfork_header_t) && !setting) { + uio_t rf_uio; + u_int8_t systemData[64]; + int rf_err; + + + /* Read the system data which starts at byte 16 */ + rf_uio = uio_create(1, 0, UIO_SYSSPACE, UIO_READ); + uio_addiov(rf_uio, (uintptr_t)systemData, sizeof(systemData)); + uio_setoffset(rf_uio, filehdr->entries[i].offset + 16); + rf_err = VNOP_READ(xvp, rf_uio, 0, context); + uio_free(rf_uio); + + if (rf_err != 0 || + bcmp(systemData, RF_EMPTY_TAG, sizeof(RF_EMPTY_TAG)) == 0) { + continue; /* skip this resource fork */ } - filehdr->entries[0].length += delta; - filehdr->entries[1].offset += delta; - - /* Fill in Attribute Header. */ - attrhdr->magic = ATTR_HDR_MAGIC; - attrhdr->debug_tag = (u_int32_t)va.va_fileid; - attrhdr->total_size = filehdr->entries[1].offset; - attrhdr->data_start = sizeof(attr_header_t); - attrhdr->data_length = 0; - attrhdr->reserved[0] = 0; - attrhdr->reserved[1] = 0; - attrhdr->reserved[2] = 0; - attrhdr->flags = 0; - attrhdr->num_attrs = 0; - - /* Push out new header */ - uio_reset(auio, 0, UIO_SYSSPACE32, UIO_WRITE); - uio_addiov(auio, (uintptr_t)filehdr, writesize); - - swap_adhdr(filehdr); - swap_attrhdr(attrhdr); - error = VNOP_WRITE(xvp, auio, 0, context); - swap_adhdr(filehdr); - /* The attribute header gets swapped below. */ } - if (SWAP32 (attrhdr->magic) != ATTR_HDR_MAGIC || - validate_attrhdr(attrhdr, ainfop->rawsize) != 0) { - printf("get_xattrinfo: invalid attribute header\n"); - continue; - } - swap_attrhdr(attrhdr); - ainfop->attrhdr = attrhdr; /* valid attribute header */ - ainfop->attr_entry = (attr_entry_t *)&attrhdr[1]; - continue; - } - if (filehdr->entries[i].type == AD_RESOURCE && - (filehdr->entries[i].length > sizeof(rsrcfork_header_t) || setting)) { ainfop->rsrcfork = &filehdr->entries[i]; if (i != (filehdr->numEntries - 1)) { printf("get_xattrinfo: resource fork not last entry\n"); @@ -1696,13 +2874,120 @@ get_xattrinfo(vnode_t xvp, int setting, attr_info_t *ainfop, vfs_context_t conte continue; } } + + /* + * See if this file looks like it is laid out correctly to contain + * extended attributes. If so, then do the following: + * + * - If we're going to be writing, try to make sure the Finder Info + * entry has room to store the extended attribute header, plus some + * space for extended attributes. + * + * - Swap and sanity check the extended attribute header and entries + * (if any). + */ + if (filehdr->numEntries == 2 && + ainfop->finderinfo == &filehdr->entries[0] && + ainfop->rsrcfork == &filehdr->entries[1] && + ainfop->finderinfo->offset == offsetof(apple_double_header_t, finfo)) { + attr_header_t *attrhdr; + attrhdr = (attr_header_t *)filehdr; + /* + * If we're going to be writing, try to make sure the Finder + * Info entry has room to store the extended attribute header, + * plus some space for extended attributes. + */ + if (setting && ainfop->finderinfo->length == FINDERINFOSIZE) { + size_t delta; + size_t writesize; + + delta = ATTR_BUF_SIZE - (filehdr->entries[0].offset + FINDERINFOSIZE); + if (ainfop->rsrcfork && filehdr->entries[1].length) { + /* Make some room before existing resource fork. */ + shift_data_down(xvp, + filehdr->entries[1].offset, + filehdr->entries[1].length, + delta, context); + writesize = sizeof(attr_header_t); + } else { + /* Create a new, empty resource fork. */ + rsrcfork_header_t *rsrcforkhdr; + + vnode_setsize(xvp, filehdr->entries[1].offset + delta, 0, context); + + /* Steal some space for an empty RF header. */ + delta -= sizeof(rsrcfork_header_t); + + bzero(&attrhdr->appledouble.pad[0], delta); + rsrcforkhdr = (rsrcfork_header_t *)((char *)filehdr + filehdr->entries[1].offset + delta); + + /* Fill in Empty Resource Fork Header. */ + init_empty_resource_fork(rsrcforkhdr); + + filehdr->entries[1].length = sizeof(rsrcfork_header_t); + writesize = ATTR_BUF_SIZE; + } + filehdr->entries[0].length += delta; + filehdr->entries[1].offset += delta; + + /* Fill in Attribute Header. */ + attrhdr->magic = ATTR_HDR_MAGIC; + attrhdr->debug_tag = (u_int32_t)va.va_fileid; + attrhdr->total_size = filehdr->entries[1].offset; + attrhdr->data_start = sizeof(attr_header_t); + attrhdr->data_length = 0; + attrhdr->reserved[0] = 0; + attrhdr->reserved[1] = 0; + attrhdr->reserved[2] = 0; + attrhdr->flags = 0; + attrhdr->num_attrs = 0; + + /* Push out new header */ + uio_reset(auio, 0, UIO_SYSSPACE, UIO_WRITE); + uio_addiov(auio, (uintptr_t)filehdr, writesize); + + swap_adhdr(filehdr); /* to big endian */ + swap_attrhdr(attrhdr, ainfop); /* to big endian */ + error = VNOP_WRITE(xvp, auio, 0, context); + swap_adhdr(filehdr); /* back to native */ + /* The attribute header gets swapped below. */ + } + } + /* + * Swap and sanity check the extended attribute header and + * entries (if any). The Finder Info content must be big enough + * to include the extended attribute header; if not, we just + * ignore it. + * + * Note that we're passing the offset + length (i.e. the end) + * of the Finder Info instead of rawsize to validate_attrhdr. + * This ensures that all extended attributes lie within the + * Finder Info content according to the AppleDouble entry. + * + * Sets ainfop->attrhdr and ainfop->attr_entry if a valid + * header was found. + */ + if (ainfop->finderinfo && + ainfop->finderinfo == &filehdr->entries[0] && + ainfop->finderinfo->length >= (sizeof(attr_header_t) - sizeof(apple_double_header_t))) { + attr_header_t *attrhdr = (attr_header_t*)filehdr; + + if ((error = check_and_swap_attrhdr(attrhdr, ainfop)) == 0) { + ainfop->attrhdr = attrhdr; /* valid attribute header */ + /* First attr_entry starts immediately following attribute header */ + ainfop->attr_entry = (attr_entry_t *)&attrhdr[1]; + } + } + error = 0; bail: - if (auio != NULL) + if (auio != NULL) { uio_free(auio); - if (buffer != NULL) + } + if (buffer != NULL) { FREE(buffer, M_TEMP); - return (error); + } + return error; } @@ -1720,54 +3005,59 @@ create_xattrfile(vnode_t xvp, u_int32_t fileid, vfs_context_t context) bzero(buffer, ATTR_BUF_SIZE); xah = (attr_header_t *)buffer; - auio = uio_create(1, 0, UIO_SYSSPACE32, UIO_WRITE); + auio = uio_create(1, 0, UIO_SYSSPACE, UIO_WRITE); uio_addiov(auio, (uintptr_t)buffer, ATTR_BUF_SIZE); rsrcforksize = sizeof(rsrcfork_header_t); rsrcforkhdr = (rsrcfork_header_t *) ((char *)buffer + ATTR_BUF_SIZE - rsrcforksize); /* Fill in Apple Double Header. */ - xah->appledouble.magic = SWAP32 (ADH_MAGIC); - xah->appledouble.version = SWAP32 (ADH_VERSION); - xah->appledouble.numEntries = SWAP16 (2); - xah->appledouble.entries[0].type = SWAP32 (AD_FINDERINFO); - xah->appledouble.entries[0].offset = SWAP32 (offsetof(apple_double_header_t, finfo)); - xah->appledouble.entries[0].length = SWAP32 (ATTR_BUF_SIZE - offsetof(apple_double_header_t, finfo) - rsrcforksize); - xah->appledouble.entries[1].type = SWAP32 (AD_RESOURCE); - xah->appledouble.entries[1].offset = SWAP32 (ATTR_BUF_SIZE - rsrcforksize); - xah->appledouble.entries[1].length = SWAP32 (rsrcforksize); + xah->appledouble.magic = SWAP32(ADH_MAGIC); + xah->appledouble.version = SWAP32(ADH_VERSION); + xah->appledouble.numEntries = SWAP16(2); + xah->appledouble.entries[0].type = SWAP32(AD_FINDERINFO); + xah->appledouble.entries[0].offset = SWAP32(offsetof(apple_double_header_t, finfo)); + xah->appledouble.entries[0].length = SWAP32(ATTR_BUF_SIZE - offsetof(apple_double_header_t, finfo) - rsrcforksize); + xah->appledouble.entries[1].type = SWAP32(AD_RESOURCE); + xah->appledouble.entries[1].offset = SWAP32(ATTR_BUF_SIZE - rsrcforksize); + xah->appledouble.entries[1].length = SWAP32(rsrcforksize); bcopy(ADH_MACOSX, xah->appledouble.filler, sizeof(xah->appledouble.filler)); /* Fill in Attribute Header. */ - xah->magic = SWAP32 (ATTR_HDR_MAGIC); - xah->debug_tag = SWAP32 (fileid); - xah->total_size = SWAP32 (ATTR_BUF_SIZE - rsrcforksize); - xah->data_start = SWAP32 (sizeof(attr_header_t)); + xah->magic = SWAP32(ATTR_HDR_MAGIC); + xah->debug_tag = SWAP32(fileid); + xah->total_size = SWAP32(ATTR_BUF_SIZE - rsrcforksize); + xah->data_start = SWAP32(sizeof(attr_header_t)); /* Fill in Empty Resource Fork Header. */ init_empty_resource_fork(rsrcforkhdr); /* Push it out. */ - error = VNOP_WRITE(xvp, auio, 0, context); + error = VNOP_WRITE(xvp, auio, IO_UNIT, context); + + /* Did we write out the full uio? */ + if (uio_resid(auio) > 0) { + error = ENOSPC; + } uio_free(auio); FREE(buffer, M_TEMP); - return (error); + return error; } static void init_empty_resource_fork(rsrcfork_header_t * rsrcforkhdr) { bzero(rsrcforkhdr, sizeof(rsrcfork_header_t)); - rsrcforkhdr->fh_DataOffset = SWAP32 (RF_FIRST_RESOURCE); - rsrcforkhdr->fh_MapOffset = SWAP32 (RF_FIRST_RESOURCE); - rsrcforkhdr->fh_MapLength = SWAP32 (RF_NULL_MAP_LENGTH); - rsrcforkhdr->mh_DataOffset = SWAP32 (RF_FIRST_RESOURCE); - rsrcforkhdr->mh_MapOffset = SWAP32 (RF_FIRST_RESOURCE); - rsrcforkhdr->mh_MapLength = SWAP32 (RF_NULL_MAP_LENGTH); - rsrcforkhdr->mh_Types = SWAP16 (RF_NULL_MAP_LENGTH - 2 ); - rsrcforkhdr->mh_Names = SWAP16 (RF_NULL_MAP_LENGTH); - rsrcforkhdr->typeCount = SWAP16 (-1); + rsrcforkhdr->fh_DataOffset = SWAP32(RF_FIRST_RESOURCE); + rsrcforkhdr->fh_MapOffset = SWAP32(RF_FIRST_RESOURCE); + rsrcforkhdr->fh_MapLength = SWAP32(RF_NULL_MAP_LENGTH); + rsrcforkhdr->mh_DataOffset = SWAP32(RF_FIRST_RESOURCE); + rsrcforkhdr->mh_MapOffset = SWAP32(RF_FIRST_RESOURCE); + rsrcforkhdr->mh_MapLength = SWAP32(RF_NULL_MAP_LENGTH); + rsrcforkhdr->mh_Types = SWAP16(RF_NULL_MAP_LENGTH - 2 ); + rsrcforkhdr->mh_Names = SWAP16(RF_NULL_MAP_LENGTH); + rsrcforkhdr->typeCount = SWAP16(-1); bcopy(RF_EMPTY_TAG, rsrcforkhdr->systemData, sizeof(RF_EMPTY_TAG)); } @@ -1784,24 +3074,28 @@ write_xattrinfo(attr_info_t *ainfop) uio_t auio; int error; - auio = uio_create(1, 0, UIO_SYSSPACE32, UIO_WRITE); + auio = uio_create(1, 0, UIO_SYSSPACE, UIO_WRITE); uio_addiov(auio, (uintptr_t)ainfop->filehdr, ainfop->iosize); swap_adhdr(ainfop->filehdr); - if (ainfop->attrhdr != NULL) - swap_attrhdr(ainfop->attrhdr); + if (ainfop->attrhdr != NULL) { + swap_attrhdr(ainfop->attrhdr, ainfop); + } error = VNOP_WRITE(ainfop->filevp, auio, 0, ainfop->context); swap_adhdr(ainfop->filehdr); - if (ainfop->attrhdr != NULL) - swap_attrhdr(ainfop->attrhdr); - return (error); + if (ainfop->attrhdr != NULL) { + swap_attrhdr(ainfop->attrhdr, ainfop); + } + uio_free(auio); + + return error; } #if BYTE_ORDER == LITTLE_ENDIAN /* - * Endian swap apple double header + * Endian swap apple double header */ static void swap_adhdr(apple_double_header_t *adh) @@ -1811,22 +3105,22 @@ swap_adhdr(apple_double_header_t *adh) count = (adh->magic == ADH_MAGIC) ? adh->numEntries : SWAP16(adh->numEntries); - adh->magic = SWAP32 (adh->magic); - adh->version = SWAP32 (adh->version); - adh->numEntries = SWAP16 (adh->numEntries); + adh->magic = SWAP32(adh->magic); + adh->version = SWAP32(adh->version); + adh->numEntries = SWAP16(adh->numEntries); for (i = 0; i < count; i++) { - adh->entries[i].type = SWAP32 (adh->entries[i].type); - adh->entries[i].offset = SWAP32 (adh->entries[i].offset); - adh->entries[i].length = SWAP32 (adh->entries[i].length); + adh->entries[i].type = SWAP32(adh->entries[i].type); + adh->entries[i].offset = SWAP32(adh->entries[i].offset); + adh->entries[i].length = SWAP32(adh->entries[i].length); } } /* - * Endian swap extended attributes header + * Endian swap extended attributes header */ static void -swap_attrhdr(attr_header_t *ah) +swap_attrhdr(attr_header_t *ah, attr_info_t* info) { attr_entry_t *ae; int count; @@ -1834,44 +3128,113 @@ swap_attrhdr(attr_header_t *ah) count = (ah->magic == ATTR_HDR_MAGIC) ? ah->num_attrs : SWAP16(ah->num_attrs); - ah->magic = SWAP32 (ah->magic); - ah->debug_tag = SWAP32 (ah->debug_tag); - ah->total_size = SWAP32 (ah->total_size); - ah->data_start = SWAP32 (ah->data_start); - ah->data_length = SWAP32 (ah->data_length); - ah->flags = SWAP16 (ah->flags); - ah->num_attrs = SWAP16 (ah->num_attrs); + ah->magic = SWAP32(ah->magic); + ah->debug_tag = SWAP32(ah->debug_tag); + ah->total_size = SWAP32(ah->total_size); + ah->data_start = SWAP32(ah->data_start); + ah->data_length = SWAP32(ah->data_length); + ah->flags = SWAP16(ah->flags); + ah->num_attrs = SWAP16(ah->num_attrs); ae = (attr_entry_t *)(&ah[1]); - for (i = 0; i < count; i++, ae = ATTR_NEXT(ae)) { - ae->offset = SWAP32 (ae->offset); - ae->length = SWAP32 (ae->length); - ae->flags = SWAP16 (ae->flags); + for (i = 0; i < count && ATTR_VALID(ae, *info); i++, ae = ATTR_NEXT(ae)) { + ae->offset = SWAP32(ae->offset); + ae->length = SWAP32(ae->length); + ae->flags = SWAP16(ae->flags); } } #endif /* - * Validate attributes header contents + * Validate and swap the attributes header contents, and each attribute's + * attr_entry_t. + * + * Note: Assumes the caller has verified that the Finder Info content is large + * enough to contain the attr_header structure itself. Therefore, we can + * swap the header fields before sanity checking them. */ static int -validate_attrhdr(attr_header_t *ah, size_t bufsize) +check_and_swap_attrhdr(attr_header_t *ah, attr_info_t *ainfop) { attr_entry_t *ae; - u_int8_t *bufend; + u_int8_t *buf_end; + u_int32_t end; int count; int i; - if (ah == NULL) - return (EINVAL); + if (ah == NULL) { + return EINVAL; + } - bufend = (u_int8_t *)ah + bufsize; - count = (ah->magic == ATTR_HDR_MAGIC) ? ah->num_attrs : SWAP16(ah->num_attrs); + if (SWAP32(ah->magic) != ATTR_HDR_MAGIC) { + return EINVAL; + } + + /* Swap the basic header fields */ + ah->magic = SWAP32(ah->magic); + ah->debug_tag = SWAP32(ah->debug_tag); + ah->total_size = SWAP32(ah->total_size); + ah->data_start = SWAP32(ah->data_start); + ah->data_length = SWAP32(ah->data_length); + ah->flags = SWAP16(ah->flags); + ah->num_attrs = SWAP16(ah->num_attrs); + + /* + * Make sure the total_size fits within the Finder Info area, and the + * extended attribute data area fits within total_size. + */ + end = ah->data_start + ah->data_length; + if (ah->total_size > ainfop->finderinfo->offset + ainfop->finderinfo->length || + end < ah->data_start || + end > ah->total_size) { + return EINVAL; + } + /* + * Make sure each of the attr_entry_t's fits within total_size. + */ + buf_end = ainfop->rawdata + ah->total_size; + count = ah->num_attrs; ae = (attr_entry_t *)(&ah[1]); - for (i = 0; i < count && (u_int8_t *)ae < bufend; i++, ae = ATTR_NEXT(ae)) { + + for (i = 0; i < count; i++) { + /* Make sure the fixed-size part of this attr_entry_t fits. */ + if ((u_int8_t *) &ae[1] > buf_end) { + return EINVAL; + } + + /* Make sure the variable-length name fits (+1 is for NUL terminator) */ + /* TODO: Make sure namelen matches strnlen(name,namelen+1)? */ + if (&ae->name[ae->namelen + 1] > buf_end) { + return EINVAL; + } + + /* Swap the attribute entry fields */ + ae->offset = SWAP32(ae->offset); + ae->length = SWAP32(ae->length); + ae->flags = SWAP16(ae->flags); + + /* Make sure the attribute content fits. */ + end = ae->offset + ae->length; + if (end < ae->offset || end > ah->total_size) { + return EINVAL; + } + + ae = ATTR_NEXT(ae); } - return (i < count ? EINVAL : 0); + + /* + * TODO: Make sure the contents of attributes don't overlap the header + * and don't overlap each other. The hard part is that we don't know + * what the actual header size is until we have looped over all of the + * variable-sized attribute entries. + * + * XXX Is there any guarantee that attribute entries are stored in + * XXX order sorted by the contents' file offset? If so, that would + * XXX make the pairwise overlap check much easier. + */ + + return 0; } // @@ -1889,41 +3252,41 @@ shift_data_down(vnode_t xvp, off_t start, size_t len, off_t delta, vfs_context_t size_t chunk, orig_chunk; char *buff; off_t pos; - ucred_t ucred = vfs_context_ucred(context); + kauth_cred_t ucred = vfs_context_ucred(context); proc_t p = vfs_context_proc(context); - + if (delta == 0 || len == 0) { return 0; } - + chunk = 4096; if (len < chunk) { chunk = len; } orig_chunk = chunk; - if (kmem_alloc(kernel_map, (vm_offset_t *)&buff, chunk)) { + if (kmem_alloc(kernel_map, (vm_offset_t *)&buff, chunk, VM_KERN_MEMORY_FILE)) { return ENOMEM; } - for(pos=start+len-chunk; pos >= start; pos-=chunk) { - ret = vn_rdwr(UIO_READ, xvp, buff, chunk, pos, UIO_SYSSPACE, IO_NODELOCKED, ucred, &iolen, p); + for (pos = start + len - chunk; pos >= start; pos -= chunk) { + ret = vn_rdwr(UIO_READ, xvp, buff, chunk, pos, UIO_SYSSPACE, IO_NODELOCKED | IO_NOAUTH, ucred, &iolen, p); if (iolen != 0) { - printf("xattr:shift_data: error reading data @ %lld (read %d of %d) (%d)\n", - pos, ret, chunk, ret); + printf("xattr:shift_data: error reading data @ %lld (read %d of %lu) (%d)\n", + pos, ret, chunk, ret); break; } - - ret = vn_rdwr(UIO_WRITE, xvp, buff, chunk, pos + delta, UIO_SYSSPACE, IO_NODELOCKED, ucred, &iolen, p); + + ret = vn_rdwr(UIO_WRITE, xvp, buff, chunk, pos + delta, UIO_SYSSPACE, IO_NODELOCKED | IO_NOAUTH, ucred, &iolen, p); if (iolen != 0) { - printf("xattr:shift_data: error writing data @ %lld (wrote %d of %d) (%d)\n", - pos+delta, ret, chunk, ret); + printf("xattr:shift_data: error writing data @ %lld (wrote %d of %lu) (%d)\n", + pos + delta, ret, chunk, ret); break; } - - if ((pos - chunk) < start) { + + if ((pos - (off_t)chunk) < start) { chunk = pos - start; - + if (chunk == 0) { // we're all done break; } @@ -1943,13 +3306,13 @@ shift_data_up(vnode_t xvp, off_t start, size_t len, off_t delta, vfs_context_t c char *buff; off_t pos; off_t end; - ucred_t ucred = vfs_context_ucred(context); + kauth_cred_t ucred = vfs_context_ucred(context); proc_t p = vfs_context_proc(context); - + if (delta == 0 || len == 0) { return 0; } - + chunk = 4096; if (len < chunk) { chunk = len; @@ -1957,28 +3320,28 @@ shift_data_up(vnode_t xvp, off_t start, size_t len, off_t delta, vfs_context_t c orig_chunk = chunk; end = start + len; - if (kmem_alloc(kernel_map, (vm_offset_t *)&buff, chunk)) { + if (kmem_alloc(kernel_map, (vm_offset_t *)&buff, chunk, VM_KERN_MEMORY_FILE)) { return ENOMEM; } - for(pos = start; pos < end; pos += chunk) { - ret = vn_rdwr(UIO_READ, xvp, buff, chunk, pos, UIO_SYSSPACE, IO_NODELOCKED, ucred, &iolen, p); + for (pos = start; pos < end; pos += chunk) { + ret = vn_rdwr(UIO_READ, xvp, buff, chunk, pos, UIO_SYSSPACE, IO_NODELOCKED | IO_NOAUTH, ucred, &iolen, p); if (iolen != 0) { - printf("xattr:shift_data: error reading data @ %lld (read %d of %d) (%d)\n", - pos, ret, chunk, ret); + printf("xattr:shift_data: error reading data @ %lld (read %d of %lu) (%d)\n", + pos, ret, chunk, ret); break; } - - ret = vn_rdwr(UIO_WRITE, xvp, buff, chunk, pos - delta, UIO_SYSSPACE, IO_NODELOCKED, ucred, &iolen, p); + + ret = vn_rdwr(UIO_WRITE, xvp, buff, chunk, pos - delta, UIO_SYSSPACE, IO_NODELOCKED | IO_NOAUTH, ucred, &iolen, p); if (iolen != 0) { - printf("xattr:shift_data: error writing data @ %lld (wrote %d of %d) (%d)\n", - pos+delta, ret, chunk, ret); + printf("xattr:shift_data: error writing data @ %lld (wrote %d of %lu) (%d)\n", + pos + delta, ret, chunk, ret); break; } - - if ((pos + chunk) > end) { + + if ((pos + (off_t)chunk) > end) { chunk = end - pos; - + if (chunk == 0) { // we're all done break; } @@ -1993,25 +3356,63 @@ static int lock_xattrfile(vnode_t xvp, short locktype, vfs_context_t context) { struct flock lf; + int error; lf.l_whence = SEEK_SET; lf.l_start = 0; lf.l_len = 0; lf.l_type = locktype; /* F_WRLCK or F_RDLCK */ /* Note: id is just a kernel address that's not a proc */ - return VNOP_ADVLOCK(xvp, (caddr_t)xvp, F_SETLK, &lf, F_FLOCK, context); + error = VNOP_ADVLOCK(xvp, (caddr_t)xvp, F_SETLK, &lf, F_FLOCK | F_WAIT, context, NULL); + return error == ENOTSUP ? 0 : error; } -static int +int unlock_xattrfile(vnode_t xvp, vfs_context_t context) { struct flock lf; + int error; lf.l_whence = SEEK_SET; lf.l_start = 0; lf.l_len = 0; lf.l_type = F_UNLCK; /* Note: id is just a kernel address that's not a proc */ - return VNOP_ADVLOCK(xvp, (caddr_t)xvp, F_UNLCK, &lf, F_FLOCK, context); + error = VNOP_ADVLOCK(xvp, (caddr_t)xvp, F_UNLCK, &lf, F_FLOCK, context, NULL); + return error == ENOTSUP ? 0 : error; +} + +#else /* CONFIG_APPLEDOUBLE */ + + +static int +default_getxattr(__unused vnode_t vp, __unused const char *name, + __unused uio_t uio, __unused size_t *size, __unused int options, + __unused vfs_context_t context) +{ + return ENOTSUP; +} + +static int +default_setxattr(__unused vnode_t vp, __unused const char *name, + __unused uio_t uio, __unused int options, __unused vfs_context_t context) +{ + return ENOTSUP; +} + +static int +default_listxattr(__unused vnode_t vp, + __unused uio_t uio, __unused size_t *size, __unused int options, + __unused vfs_context_t context) +{ + return ENOTSUP; +} + +static int +default_removexattr(__unused vnode_t vp, __unused const char *name, + __unused int options, __unused vfs_context_t context) +{ + return ENOTSUP; } +#endif /* CONFIG_APPLEDOUBLE */