From a9975cd18d07780a060a773e8597182debc6b9c4 Mon Sep 17 00:00:00 2001 From: Valient Gough Date: Sun, 16 Aug 2015 17:32:39 -0700 Subject: [PATCH] add xattr translation --- encfs/encfs.cpp | 130 +++++++++++++++++++++++++++++------------------- 1 file changed, 78 insertions(+), 52 deletions(-) diff --git a/encfs/encfs.cpp b/encfs/encfs.cpp index f128834..cee5a64 100644 --- a/encfs/encfs.cpp +++ b/encfs/encfs.cpp @@ -17,20 +17,25 @@ #include "encfs.h" +#include +#include +#include +#include +#include #include #include +#include #include +#include #include #include #include #include #include +#include #include -#include -#include -#include -#include -#include +#include + #ifdef linux #include #endif @@ -43,9 +48,6 @@ #include #include -#include -#include -#include #include "Context.h" #include "DirNode.h" @@ -60,10 +62,6 @@ namespace rlog { class RLogChannel; } // namespace rlog -#ifndef MIN -#define MIN(a, b) (((a) < (b)) ? (a) : (b)) -#endif - #define ESUCCESS 0 using namespace std; @@ -71,7 +69,14 @@ using namespace std::placeholders; using namespace rlog; using rel::Lock; -#define GET_FN(ctx, finfo) ctx->getNode((void *)(uintptr_t) finfo->fh) +#define GET_FN(ctx, finfo) ctx->getNode((void *)(uintptr_t)finfo->fh) + +// XAttr prefix replacement. +// Replaces "com.apple." with "encfs_apl." when storing xattrs. +// TODO: future versions of encfs should encrypt xattrs, making this +// unnecessary. +static const char _attr_apple[] = "com.apple."; +static const char _attr_apple_internal[] = "encfs_apl."; static RLogChannel *Info = DEF_CHANNEL("info", Log_Info); @@ -566,7 +571,7 @@ int encfs_release(const char *path, struct fuse_file_info *finfo) { EncFS_Context *ctx = context(); try { - ctx->eraseNode(path, (void *)(uintptr_t) finfo->fh); + ctx->eraseNode(path, (void *)(uintptr_t)finfo->fh); return ESUCCESS; } catch (rlog::Error &err) { rError("error caught in release"); @@ -634,77 +639,97 @@ int encfs_statfs(const char *path, struct statvfs *st) { #ifdef HAVE_XATTR -#ifdef XATTR_ADD_OPT +typedef std::unique_ptr> + AttrPtr; +void NoFree(const char *) {} + +AttrPtr extToInternalAttr(const char *attr) { + if (!strncmp(attr, _attr_apple, sizeof(_attr_apple) - 1)) { + char *out = strdup(attr); + memcpy(out, _attr_apple_internal, sizeof(_attr_apple_internal) - 1); + return AttrPtr(out, (void (*)(const char *))std::free); + } else { + return AttrPtr(attr, NoFree); + } +} + +void internalToExtAttr(char *attr) { + if (!strncmp(attr, _attr_apple_internal, sizeof(_attr_apple_internal) - 1)) { + memcpy(attr, _attr_apple, sizeof(_attr_apple) - 1); + } +} + int _do_setxattr(EncFS_Context *, const string &cyName, const char *name, const char *value, size_t size, uint32_t pos) { - int options = 0; - return ::setxattr(cyName.c_str(), name, value, size, pos, options); +#ifdef XATTR_ADD_OPT + return ::setxattr(cyName.c_str(), name, value, size, pos, XATTR_NOFOLLOW); +#else + return ::setxattr(cyName.c_str(), name, value, size, 0); +#endif } int encfs_setxattr(const char *path, const char *name, const char *value, - size_t size, int flags, uint32_t position) { + size_t size, int flags, uint32_t pos) { if (isReadOnly(NULL)) return -EROFS; (void)flags; - return withCipherPath("setxattr", path, bind(_do_setxattr, _1, _2, name, - value, size, position)); -} -#else -int _do_setxattr(EncFS_Context *, const string &cyName, const char *name, - const char *value, size_t size, int flags) { - return ::setxattr(cyName.c_str(), name, value, size, flags); + + AttrPtr attr = extToInternalAttr(name); + return withCipherPath("setxattr", path, bind(_do_setxattr, _1, _2, attr.get(), + value, size, pos)); } int encfs_setxattr(const char *path, const char *name, const char *value, size_t size, int flags) { - if (isReadOnly(NULL)) return -EROFS; - return withCipherPath("setxattr", path, - bind(_do_setxattr, _1, _2, name, value, size, flags)); + return encfs_setxattr(path, name, value, size, flags, uint32_t(0)); } -#endif -#ifdef XATTR_ADD_OPT int _do_getxattr(EncFS_Context *, const string &cyName, const char *name, void *value, size_t size, uint32_t pos) { - int options = 0; - return ::getxattr(cyName.c_str(), name, value, size, pos, options); +#ifdef XATTR_ADD_OPT + return ::getxattr(cyName.c_str(), name, value, size, pos, XATTR_NOFOLLOW); +#else + return ::getxattr(cyName.c_str(), name, value, size); +#endif } int encfs_getxattr(const char *path, const char *name, char *value, size_t size, - uint32_t position) { + uint32_t pos) { + AttrPtr attr = extToInternalAttr(name); return withCipherPath( "getxattr", path, - bind(_do_getxattr, _1, _2, name, (void *)value, size, position), true); -} -#else -int _do_getxattr(EncFS_Context *, const string &cyName, const char *name, - void *value, size_t size) { - return ::getxattr(cyName.c_str(), name, value, size); + bind(_do_getxattr, _1, _2, attr.get(), (void *)value, size, pos), true); } int encfs_getxattr(const char *path, const char *name, char *value, size_t size) { - return withCipherPath("getxattr", path, - bind(_do_getxattr, _1, _2, name, (void *)value, size), - true); + return encfs_getxattr(path, name, value, size, uint32_t(0)); } -#endif int _do_listxattr(EncFS_Context *, const string &cyName, char *list, size_t size) { #ifdef XATTR_ADD_OPT - int options = 0; - int res = ::listxattr(cyName.c_str(), list, size, options); + return ::listxattr(cyName.c_str(), list, size, XATTR_NOFOLLOW); #else - int res = ::listxattr(cyName.c_str(), list, size); + return ::listxattr(cyName.c_str(), list, size); #endif - return (res == -1) ? -errno : res; } int encfs_listxattr(const char *path, char *list, size_t size) { - return withCipherPath("listxattr", path, - bind(_do_listxattr, _1, _2, list, size), true); + int res = withCipherPath("listxattr", path, + bind(_do_listxattr, _1, _2, list, size), true); + if (list) { + size_t len = 0; + char *curr = list; + while (len < res) { + internalToExtAttr(curr); + size_t el_len = strlen(curr) + 1; + curr += el_len; + len += el_len; + } + } + + return res; } int _do_removexattr(EncFS_Context *, const string &cyName, const char *name) { #ifdef XATTR_ADD_OPT - int options = 0; - int res = ::removexattr(cyName.c_str(), name, options); + int res = ::removexattr(cyName.c_str(), name, XATTR_NOFOLLOW); #else int res = ::removexattr(cyName.c_str(), name); #endif @@ -714,8 +739,9 @@ int _do_removexattr(EncFS_Context *, const string &cyName, const char *name) { int encfs_removexattr(const char *path, const char *name) { if (isReadOnly(NULL)) return -EROFS; + AttrPtr attr = extToInternalAttr(name); return withCipherPath("removexattr", path, - bind(_do_removexattr, _1, _2, name)); + bind(_do_removexattr, _1, _2, attr.get())); } #endif // HAVE_XATTR