Verified Commit e155dd60 authored by Tommaso Tocci's avatar Tommaso Tocci
Browse files

intercept mkdir/mkdirat

parent 4c8fc68a

ifs/include/preload/hooks.hpp

+1 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ int hook_dup(unsigned int fd); 
int hook_dup2(unsigned int oldfd, unsigned int newfd);

int hook_dup3(unsigned int oldfd, unsigned int newfd, int flags);

int hook_getdents(unsigned int fd, struct linux_dirent *dirp, unsigned int count);

int hook_mkdirat(int dirfd, const char * cpath, mode_t mode);





#endif

ifs/src/preload/hooks.cpp

+40 −0
Original line number Diff line number Diff line
@@ -198,3 +198,43 @@ int hook_getdents(unsigned int fd, struct linux_dirent *dirp, unsigned int count 
    }

    return syscall_no_intercept(SYS_getdents, fd, dirp, count);

}



int hook_mkdirat(int dirfd, const char * cpath, mode_t mode) {

    if(cpath == nullptr || cpath[0] == '\0') {

        CTX->log()->error("{}() path is invalid", __func__);

        return -EINVAL;

    }



    CTX->log()->trace("{}() called with fd: {}, path: {}, mode: {}",

                      __func__, dirfd, cpath, mode);



    std::string resolved;



    if((cpath[0] == PSP) || (dirfd == AT_FDCWD)) {

        // cpath is absolute or relative to CWD

        if (CTX->relativize_path(cpath, resolved)) {

            return with_errno(adafs_mk_node(resolved, mode | S_IFDIR));

        }

    } else {

        // cpath is relative

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

            //TODO relative cpath could still lead to our FS

            return syscall_no_intercept(SYS_mkdirat, dirfd, cpath, mode);

        }



        auto dir = CTX->file_map()->get_dir(dirfd);

        if(dir == nullptr) {

            CTX->log()->error("{}() dirfd is not a directory ", __func__);

            return -ENOTDIR;

        }



        std::string path = CTX->mountdir();

        path.append(dir->path());

        path.push_back(PSP);

        path.append(cpath);

        if(resolve_path(path, resolved)) {

            return with_errno(adafs_mk_node(resolved, mode | S_IFDIR));

        }

    }

    return syscall_no_intercept(SYS_mkdirat, dirfd, resolved.c_str(), mode);

}

ifs/src/preload/intercept.cpp

+12 −0
Original line number Diff line number Diff line
@@ -104,6 +104,18 @@ static inline int hook(long syscall_number, 
                                static_cast<unsigned int>(arg2));

        break;



    case SYS_mkdirat:

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

                               reinterpret_cast<const char *>(arg1),

                               static_cast<mode_t>(arg2));

        break;



    case SYS_mkdir:

        *result = hook_mkdirat(AT_FDCWD,

                               reinterpret_cast<const char *>(arg0),

                               static_cast<mode_t>(arg1));

        break;



    default:

        /*

         * Ignore any other syscalls