Commit 337d171c authored by Marc Vef's avatar Marc Vef
Browse files

Added three access and lookup configurations: 

- should permissions be checked when access() is called or discarded. Default off
//#define CHECK_ACCESS
- If access permissions should be checked while opening a file. Default off
//#define CHECK_ACCESS_DURING_OPEN
- If disabled, a file or directory is always presumed to be there (even if it is not). No check is executed. Default on.
#define DO_LOOKUP
parent 49a77aac

ifs/configure.hpp

+5 −1
Original line number Diff line number Diff line
@@ -30,8 +30,12 @@ 
#define MDATA_USE_BLOCKS false

#define MDATA_USE_SIZE true // XXX to be added in ADAFS_DATA. currently on by default



// should permissions be checked when access() is called or discarded

//#define CHECK_ACCESS

// If access permissions should be checked while opening a file

//#define CHECK_ACCESS //unused

//#define CHECK_ACCESS_DURING_OPEN

// If disabled, a file or directory is always presumed to be there (even if it is not). No check is executed

#define DO_LOOKUP



// Write-ahead logging of rocksdb

//#define RDB_WOL

ifs/src/preload/adafs_functions.cpp

+28 −3
Original line number Diff line number Diff line
@@ -10,9 +10,26 @@ int adafs_open(const std::string& path, mode_t mode, int flags) { 
    auto fd = file_map.add(path, (flags & O_APPEND) != 0);

    // TODO look up if file exists configurable

    if (flags & O_CREAT)

        err = adafs_mk_node(path, mode);

    else

        err = adafs_access(path, F_OK);

        // no access check required here. If one is using our FS they have the permissions.

        err = rpc_send_mk_node(path, mode);

    else {

        auto mask = F_OK; // F_OK == 0

#if defined(CHECK_ACCESS_DURING_OPEN)

        if ((mode & S_IRUSR) || (mode & S_IRGRP) || (mode & S_IROTH))

            mask = mask & R_OK;

        if ((mode & S_IWUSR) || (mode & S_IWGRP) || (mode & S_IWOTH))

            mask = mask & W_OK;

        if ((mode & S_IXUSR) || (mode & S_IXGRP) || (mode & S_IXOTH))

            mask = mask & X_OK;

#endif

#if defined(DO_LOOKUP)

        // check if file exists

        err = rpc_send_access(path, mask);

#else

        // file is assumed to be existing, even though it might not

        err = 0;

#endif

    }

    if (err == 0)

        return fd;

    else {
@@ -30,7 +47,15 @@ int adafs_rm_node(const std::string& path) { 
}



int adafs_access(const std::string& path, const int mask) {

#if !defined(DO_LOOKUP)

    // object is assumed to be existing, even though it might not

    return 0;

#endif

#if defined(CHECK_ACCESS_DURING_OPEN)

    return rpc_send_access(path, mask);

#else

    return rpc_send_access(path, F_OK); // Only check for file exists

#endif

}



// TODO combine adafs_stat and adafs_stat64