Unverified Commit 72dc750d authored by Tommaso Tocci's avatar Tommaso Tocci
Browse files

intercept fcntl

parent 48592d5f

include/client/hooks.hpp

+1 −0
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ int hook_mkdirat(int dirfd, const char * cpath, mode_t mode); 
int hook_chdir(const char* path);

int hook_fchdir(unsigned int fd);

int hook_getcwd(char * buf, unsigned long size);

int hook_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg);





#endif

src/client/hooks.cpp

+61 −0
Original line number Diff line number Diff line
@@ -371,3 +371,64 @@ int hook_getcwd(char * buf, unsigned long size) { 
    strcpy(buf, CTX->cwd().c_str());

    return (CTX->cwd().size() + 1);

}



int hook_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg) {

    CTX->log()->trace("{}() called with fd {}, cmd {}, arg {}", __func__, fd, cmd, arg);

    if (!CTX->file_map()->exist(fd)) {

        return syscall_no_intercept(SYS_fcntl, fd, cmd, arg);

    }

    int ret;

    switch (cmd) {



        case F_DUPFD:

            CTX->log()->trace("{}() F_DUPFD on fd {}", __func__, fd);

            return with_errno(adafs_dup(fd));



        case F_DUPFD_CLOEXEC:

            CTX->log()->trace("{}() F_DUPFD_CLOEXEC on fd {}", __func__, fd);

            ret = adafs_dup(fd);

            if(ret == -1) {

                return -errno;

            }

            CTX->file_map()->get(fd)->set_flag(OpenFile_flags::cloexec, true);

            return ret;



        case F_GETFD:

            CTX->log()->trace("{}() F_GETFD on fd {}", __func__, fd);

            if(CTX->file_map()->get(fd)

                    ->get_flag(OpenFile_flags::cloexec)) {

                return FD_CLOEXEC;

            }

            return 0;



        case F_GETFL:

            CTX->log()->trace("{}() F_GETFL on fd {}", __func__, fd);

            ret = 0;

            if(CTX->file_map()->get(fd)

                    ->get_flag(OpenFile_flags::rdonly)) {

                ret |= O_RDONLY;

            }

            if(CTX->file_map()->get(fd)

                    ->get_flag(OpenFile_flags::wronly)) {

                ret |= O_WRONLY;

            }

            if(CTX->file_map()->get(fd)

                    ->get_flag(OpenFile_flags::rdwr)) {

                ret |= O_RDWR;

            }

            return ret;



        case F_SETFD:

            CTX->log()->trace("{}() [fd: {}, cmd: F_SETFD, FD_CLOEXEC: {}]",

                __func__, fd, (arg & FD_CLOEXEC));

            CTX->file_map()->get(fd)

                ->set_flag(OpenFile_flags::cloexec, (arg & FD_CLOEXEC));

            return 0;





        default:

            CTX->log()->error("{}() unrecognized command {} on fd {}",

                    __func__, cmd, fd);

            return -ENOTSUP;

    }

}

src/client/intercept.cpp

+6 −0
Original line number Diff line number Diff line
@@ -184,6 +184,12 @@ static inline int hook(long syscall_number, 
                               static_cast<unsigned long>(arg1));

        break;



    case SYS_fcntl:

        *result = hook_fcntl(static_cast<unsigned int>(arg0),

                             static_cast<unsigned int>(arg1),

                             static_cast<unsigned long>(arg2));

        break;



    default:

        /*

         * Ignore any other syscalls