/*- * Copyright (c) 2015 Nuxi, https://nuxi.nl/ * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD: stable/11/sys/compat/cloudabi/cloudabi_file.c 324250 2017-10-04 07:35:01Z ed $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static MALLOC_DEFINE(M_CLOUDABI_PATH, "cloudabipath", "CloudABI pathnames"); /* * Copying pathnames from userspace to kernelspace. * * Unlike most operating systems, CloudABI doesn't use null-terminated * pathname strings. Processes always pass pathnames to the kernel by * providing a base pointer and a length. This has a couple of reasons: * * - It makes it easier to use CloudABI in combination with programming * languages other than C, that may use non-null terminated strings. * - It allows for calling system calls on individual components of the * pathname without modifying the input string. * * The function below copies in pathname strings and null-terminates it. * It also ensure that the string itself does not contain any null * bytes. * * TODO(ed): Add an abstraction to vfs_lookup.c that allows us to pass * in unterminated pathname strings, so we can do away with * the copying. */ static int copyin_path(const char *uaddr, size_t len, char **result) { char *buf; int error; if (len >= PATH_MAX) return (ENAMETOOLONG); buf = malloc(len + 1, M_CLOUDABI_PATH, M_WAITOK); error = copyin(uaddr, buf, len); if (error != 0) { free(buf, M_CLOUDABI_PATH); return (error); } if (memchr(buf, '\0', len) != NULL) { free(buf, M_CLOUDABI_PATH); return (EINVAL); } buf[len] = '\0'; *result = buf; return (0); } static void cloudabi_freestr(char *buf) { free(buf, M_CLOUDABI_PATH); } int cloudabi_sys_file_advise(struct thread *td, struct cloudabi_sys_file_advise_args *uap) { int advice; switch (uap->advice) { case CLOUDABI_ADVICE_DONTNEED: advice = POSIX_FADV_DONTNEED; break; case CLOUDABI_ADVICE_NOREUSE: advice = POSIX_FADV_NOREUSE; break; case CLOUDABI_ADVICE_NORMAL: advice = POSIX_FADV_NORMAL; break; case CLOUDABI_ADVICE_RANDOM: advice = POSIX_FADV_RANDOM; break; case CLOUDABI_ADVICE_SEQUENTIAL: advice = POSIX_FADV_SEQUENTIAL; break; case CLOUDABI_ADVICE_WILLNEED: advice = POSIX_FADV_WILLNEED; break; default: return (EINVAL); } return (kern_posix_fadvise(td, uap->fd, uap->offset, uap->len, advice)); } int cloudabi_sys_file_allocate(struct thread *td, struct cloudabi_sys_file_allocate_args *uap) { return (kern_posix_fallocate(td, uap->fd, uap->offset, uap->len)); } int cloudabi_sys_file_create(struct thread *td, struct cloudabi_sys_file_create_args *uap) { char *path; int error; error = copyin_path(uap->path, uap->path_len, &path); if (error != 0) return (error); /* * CloudABI processes cannot interact with UNIX credentials and * permissions. Depend on the umask that is set prior to * execution to restrict the file permissions. */ switch (uap->type) { case CLOUDABI_FILETYPE_DIRECTORY: error = kern_mkdirat(td, uap->fd, path, UIO_SYSSPACE, 0777); break; default: error = EINVAL; break; } cloudabi_freestr(path); return (error); } int cloudabi_sys_file_link(struct thread *td, struct cloudabi_sys_file_link_args *uap) { char *path1, *path2; int error; error = copyin_path(uap->path1, uap->path1_len, &path1); if (error != 0) return (error); error = copyin_path(uap->path2, uap->path2_len, &path2); if (error != 0) { cloudabi_freestr(path1); return (error); } error = kern_linkat(td, uap->fd1.fd, uap->fd2, path1, path2, UIO_SYSSPACE, (uap->fd1.flags & CLOUDABI_LOOKUP_SYMLINK_FOLLOW) ? FOLLOW : NOFOLLOW); cloudabi_freestr(path1); cloudabi_freestr(path2); return (error); } int cloudabi_sys_file_open(struct thread *td, struct cloudabi_sys_file_open_args *uap) { cloudabi_fdstat_t fds; cap_rights_t rights; struct filecaps fcaps = {}; struct nameidata nd; struct file *fp; struct vnode *vp; char *path; int error, fd, fflags; bool read, write; error = copyin(uap->fds, &fds, sizeof(fds)); if (error != 0) return (error); /* All the requested rights should be set on the descriptor. */ error = cloudabi_convert_rights( fds.fs_rights_base | fds.fs_rights_inheriting, &rights); if (error != 0) return (error); cap_rights_set(&rights, CAP_LOOKUP); /* Convert rights to corresponding access mode. */ read = (fds.fs_rights_base & (CLOUDABI_RIGHT_FD_READ | CLOUDABI_RIGHT_FILE_READDIR | CLOUDABI_RIGHT_MEM_MAP_EXEC)) != 0; write = (fds.fs_rights_base & (CLOUDABI_RIGHT_FD_DATASYNC | CLOUDABI_RIGHT_FD_WRITE | CLOUDABI_RIGHT_FILE_ALLOCATE | CLOUDABI_RIGHT_FILE_STAT_FPUT_SIZE)) != 0; fflags = write ? read ? FREAD | FWRITE : FWRITE : FREAD; /* Convert open flags. */ if ((uap->oflags & CLOUDABI_O_CREAT) != 0) { fflags |= O_CREAT; cap_rights_set(&rights, CAP_CREATE); } if ((uap->oflags & CLOUDABI_O_DIRECTORY) != 0) fflags |= O_DIRECTORY; if ((uap->oflags & CLOUDABI_O_EXCL) != 0) fflags |= O_EXCL; if ((uap->oflags & CLOUDABI_O_TRUNC) != 0) { fflags |= O_TRUNC; cap_rights_set(&rights, CAP_FTRUNCATE); } if ((fds.fs_flags & CLOUDABI_FDFLAG_APPEND) != 0) fflags |= O_APPEND; if ((fds.fs_flags & CLOUDABI_FDFLAG_NONBLOCK) != 0) fflags |= O_NONBLOCK; if ((fds.fs_flags & (CLOUDABI_FDFLAG_SYNC | CLOUDABI_FDFLAG_DSYNC | CLOUDABI_FDFLAG_RSYNC)) != 0) { fflags |= O_SYNC; cap_rights_set(&rights, CAP_FSYNC); } if ((uap->dirfd.flags & CLOUDABI_LOOKUP_SYMLINK_FOLLOW) == 0) fflags |= O_NOFOLLOW; if (write && (fflags & (O_APPEND | O_TRUNC)) == 0) cap_rights_set(&rights, CAP_SEEK); /* Allocate new file descriptor. */ error = falloc_noinstall(td, &fp); if (error != 0) return (error); fp->f_flag = fflags & FMASK; /* Open path. */ error = copyin_path(uap->path, uap->path_len, &path); if (error != 0) { fdrop(fp, td); return (error); } NDINIT_ATRIGHTS(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, path, uap->dirfd.fd, &rights, td); error = vn_open(&nd, &fflags, 0777 & ~td->td_proc->p_fd->fd_cmask, fp); cloudabi_freestr(path); if (error != 0) { /* Custom operations provided. */ if (error == ENXIO && fp->f_ops != &badfileops) goto success; /* * POSIX compliance: return ELOOP in case openat() is * called on a symbolic link and O_NOFOLLOW is set. */ if (error == EMLINK) error = ELOOP; fdrop(fp, td); return (error); } NDFREE(&nd, NDF_ONLY_PNBUF); filecaps_free(&nd.ni_filecaps); fp->f_vnode = vp = nd.ni_vp; /* Install vnode operations if no custom operations are provided. */ if (fp->f_ops == &badfileops) { fp->f_seqcount = 1; finit(fp, (fflags & FMASK) | (fp->f_flag & FHASLOCK), DTYPE_VNODE, vp, &vnops); } VOP_UNLOCK(vp, 0); /* Truncate file. */ if (fflags & O_TRUNC) { error = fo_truncate(fp, 0, td->td_ucred, td); if (error != 0) { fdrop(fp, td); return (error); } } success: /* Determine which Capsicum rights to set on the file descriptor. */ cloudabi_remove_conflicting_rights(cloudabi_convert_filetype(fp), &fds.fs_rights_base, &fds.fs_rights_inheriting); cloudabi_convert_rights(fds.fs_rights_base | fds.fs_rights_inheriting, &fcaps.fc_rights); if (cap_rights_is_set(&fcaps.fc_rights)) fcaps.fc_fcntls = CAP_FCNTL_SETFL; error = finstall(td, fp, &fd, fflags, &fcaps); fdrop(fp, td); if (error != 0) return (error); td->td_retval[0] = fd; return (0); } /* Converts a FreeBSD directory entry structure and writes it to userspace. */ static int write_dirent(struct dirent *bde, cloudabi_dircookie_t cookie, struct uio *uio) { cloudabi_dirent_t cde = { .d_next = cookie, .d_ino = bde->d_fileno, .d_namlen = bde->d_namlen, }; size_t len; int error; /* Convert file type. */ switch (bde->d_type) { case DT_BLK: cde.d_type = CLOUDABI_FILETYPE_BLOCK_DEVICE; break; case DT_CHR: cde.d_type = CLOUDABI_FILETYPE_CHARACTER_DEVICE; break; case DT_DIR: cde.d_type = CLOUDABI_FILETYPE_DIRECTORY; break; case DT_FIFO: cde.d_type = CLOUDABI_FILETYPE_SOCKET_STREAM; break; case DT_LNK: cde.d_type = CLOUDABI_FILETYPE_SYMBOLIC_LINK; break; case DT_REG: cde.d_type = CLOUDABI_FILETYPE_REGULAR_FILE; break; case DT_SOCK: /* The exact socket type cannot be derived. */ cde.d_type = CLOUDABI_FILETYPE_SOCKET_STREAM; break; default: cde.d_type = CLOUDABI_FILETYPE_UNKNOWN; break; } /* Write directory entry structure. */ len = sizeof(cde) < uio->uio_resid ? sizeof(cde) : uio->uio_resid; error = uiomove(&cde, len, uio); if (error != 0) return (error); /* Write filename. */ len = bde->d_namlen < uio->uio_resid ? bde->d_namlen : uio->uio_resid; return (uiomove(bde->d_name, len, uio)); } int cloudabi_sys_file_readdir(struct thread *td, struct cloudabi_sys_file_readdir_args *uap) { struct iovec iov = { .iov_base = uap->buf, .iov_len = uap->buf_len }; struct uio uio = { .uio_iov = &iov, .uio_iovcnt = 1, .uio_resid = iov.iov_len, .uio_segflg = UIO_USERSPACE, .uio_rw = UIO_READ, .uio_td = td }; struct file *fp; struct vnode *vp; void *readbuf; cap_rights_t rights; cloudabi_dircookie_t offset; int error; /* Obtain directory vnode. */ error = getvnode(td, uap->fd, cap_rights_init(&rights, CAP_READ), &fp); if (error != 0) { if (error == EINVAL) return (ENOTDIR); return (error); } if ((fp->f_flag & FREAD) == 0) { fdrop(fp, td); return (EBADF); } /* * Call VOP_READDIR() and convert resulting data until the user * provided buffer is filled. */ readbuf = malloc(MAXBSIZE, M_TEMP, M_WAITOK); offset = uap->cookie; vp = fp->f_vnode; while (uio.uio_resid > 0) { struct iovec readiov = { .iov_base = readbuf, .iov_len = MAXBSIZE }; struct uio readuio = { .uio_iov = &readiov, .uio_iovcnt = 1, .uio_rw = UIO_READ, .uio_segflg = UIO_SYSSPACE, .uio_td = td, .uio_resid = MAXBSIZE, .uio_offset = offset }; struct dirent *bde; unsigned long *cookies, *cookie; size_t readbuflen; int eof, ncookies; /* Validate file type. */ vn_lock(vp, LK_SHARED | LK_RETRY); if (vp->v_type != VDIR) { VOP_UNLOCK(vp, 0); error = ENOTDIR; goto done; } #ifdef MAC error = mac_vnode_check_readdir(td->td_ucred, vp); if (error != 0) { VOP_UNLOCK(vp, 0); goto done; } #endif /* MAC */ /* Read new directory entries. */ cookies = NULL; ncookies = 0; error = VOP_READDIR(vp, &readuio, fp->f_cred, &eof, &ncookies, &cookies); VOP_UNLOCK(vp, 0); if (error != 0) goto done; /* Convert entries to CloudABI's format. */ readbuflen = MAXBSIZE - readuio.uio_resid; bde = readbuf; cookie = cookies; while (readbuflen >= offsetof(struct dirent, d_name) && uio.uio_resid > 0 && ncookies > 0) { /* Ensure that the returned offset always increases. */ if (readbuflen >= bde->d_reclen && bde->d_fileno != 0 && *cookie > offset) { error = write_dirent(bde, *cookie, &uio); if (error != 0) { free(cookies, M_TEMP); goto done; } } if (offset < *cookie) offset = *cookie; ++cookie; --ncookies; readbuflen -= bde->d_reclen; bde = (struct dirent *)((char *)bde + bde->d_reclen); } free(cookies, M_TEMP); if (eof) break; } done: fdrop(fp, td); free(readbuf, M_TEMP); if (error != 0) return (error); /* Return number of bytes copied to userspace. */ td->td_retval[0] = uap->buf_len - uio.uio_resid; return (0); } int cloudabi_sys_file_readlink(struct thread *td, struct cloudabi_sys_file_readlink_args *uap) { char *path; int error; error = copyin_path(uap->path, uap->path_len, &path); if (error != 0) return (error); error = kern_readlinkat(td, uap->fd, path, UIO_SYSSPACE, uap->buf, UIO_USERSPACE, uap->buf_len); cloudabi_freestr(path); return (error); } int cloudabi_sys_file_rename(struct thread *td, struct cloudabi_sys_file_rename_args *uap) { char *old, *new; int error; error = copyin_path(uap->path1, uap->path1_len, &old); if (error != 0) return (error); error = copyin_path(uap->path2, uap->path2_len, &new); if (error != 0) { cloudabi_freestr(old); return (error); } error = kern_renameat(td, uap->fd1, old, uap->fd2, new, UIO_SYSSPACE); cloudabi_freestr(old); cloudabi_freestr(new); return (error); } /* Converts a FreeBSD stat structure to a CloudABI stat structure. */ static void convert_stat(const struct stat *sb, cloudabi_filestat_t *csb) { cloudabi_filestat_t res = { .st_dev = sb->st_dev, .st_ino = sb->st_ino, .st_nlink = sb->st_nlink, .st_size = sb->st_size, }; cloudabi_convert_timespec(&sb->st_atim, &res.st_atim); cloudabi_convert_timespec(&sb->st_mtim, &res.st_mtim); cloudabi_convert_timespec(&sb->st_ctim, &res.st_ctim); *csb = res; } int cloudabi_sys_file_stat_fget(struct thread *td, struct cloudabi_sys_file_stat_fget_args *uap) { struct stat sb; cloudabi_filestat_t csb; struct file *fp; cap_rights_t rights; cloudabi_filetype_t filetype; int error; /* Fetch file descriptor attributes. */ error = fget(td, uap->fd, cap_rights_init(&rights, CAP_FSTAT), &fp); if (error != 0) return (error); error = fo_stat(fp, &sb, td->td_ucred, td); if (error != 0) { fdrop(fp, td); return (error); } filetype = cloudabi_convert_filetype(fp); fdrop(fp, td); /* Convert attributes to CloudABI's format. */ convert_stat(&sb, &csb); csb.st_filetype = filetype; return (copyout(&csb, uap->buf, sizeof(csb))); } /* Converts timestamps to arguments to futimens() and utimensat(). */ static void convert_utimens_arguments(const cloudabi_filestat_t *fs, cloudabi_fsflags_t flags, struct timespec *ts) { if ((flags & CLOUDABI_FILESTAT_ATIM_NOW) != 0) { ts[0].tv_nsec = UTIME_NOW; } else if ((flags & CLOUDABI_FILESTAT_ATIM) != 0) { ts[0].tv_sec = fs->st_atim / 1000000000; ts[0].tv_nsec = fs->st_atim % 1000000000; } else { ts[0].tv_nsec = UTIME_OMIT; } if ((flags & CLOUDABI_FILESTAT_MTIM_NOW) != 0) { ts[1].tv_nsec = UTIME_NOW; } else if ((flags & CLOUDABI_FILESTAT_MTIM) != 0) { ts[1].tv_sec = fs->st_mtim / 1000000000; ts[1].tv_nsec = fs->st_mtim % 1000000000; } else { ts[1].tv_nsec = UTIME_OMIT; } } int cloudabi_sys_file_stat_fput(struct thread *td, struct cloudabi_sys_file_stat_fput_args *uap) { cloudabi_filestat_t fs; struct timespec ts[2]; int error; error = copyin(uap->buf, &fs, sizeof(fs)); if (error != 0) return (error); /* * Only support truncation and timestamp modification separately * for now, to prevent unnecessary code duplication. */ if ((uap->flags & CLOUDABI_FILESTAT_SIZE) != 0) { /* Call into kern_ftruncate() for file truncation. */ if ((uap->flags & ~CLOUDABI_FILESTAT_SIZE) != 0) return (EINVAL); return (kern_ftruncate(td, uap->fd, fs.st_size)); } else if ((uap->flags & (CLOUDABI_FILESTAT_ATIM | CLOUDABI_FILESTAT_ATIM_NOW | CLOUDABI_FILESTAT_MTIM | CLOUDABI_FILESTAT_MTIM_NOW)) != 0) { /* Call into kern_futimens() for timestamp modification. */ if ((uap->flags & ~(CLOUDABI_FILESTAT_ATIM | CLOUDABI_FILESTAT_ATIM_NOW | CLOUDABI_FILESTAT_MTIM | CLOUDABI_FILESTAT_MTIM_NOW)) != 0) return (EINVAL); convert_utimens_arguments(&fs, uap->flags, ts); return (kern_futimens(td, uap->fd, ts, UIO_SYSSPACE)); } return (EINVAL); } int cloudabi_sys_file_stat_get(struct thread *td, struct cloudabi_sys_file_stat_get_args *uap) { struct stat sb; cloudabi_filestat_t csb; char *path; int error; error = copyin_path(uap->path, uap->path_len, &path); if (error != 0) return (error); error = kern_statat(td, (uap->fd.flags & CLOUDABI_LOOKUP_SYMLINK_FOLLOW) != 0 ? 0 : AT_SYMLINK_NOFOLLOW, uap->fd.fd, path, UIO_SYSSPACE, &sb, NULL); cloudabi_freestr(path); if (error != 0) return (error); /* Convert results and return them. */ convert_stat(&sb, &csb); if (S_ISBLK(sb.st_mode)) csb.st_filetype = CLOUDABI_FILETYPE_BLOCK_DEVICE; else if (S_ISCHR(sb.st_mode)) csb.st_filetype = CLOUDABI_FILETYPE_CHARACTER_DEVICE; else if (S_ISDIR(sb.st_mode)) csb.st_filetype = CLOUDABI_FILETYPE_DIRECTORY; else if (S_ISFIFO(sb.st_mode)) csb.st_filetype = CLOUDABI_FILETYPE_SOCKET_STREAM; else if (S_ISREG(sb.st_mode)) csb.st_filetype = CLOUDABI_FILETYPE_REGULAR_FILE; else if (S_ISSOCK(sb.st_mode)) { /* Inaccurate, but the best that we can do. */ csb.st_filetype = CLOUDABI_FILETYPE_SOCKET_STREAM; } else if (S_ISLNK(sb.st_mode)) csb.st_filetype = CLOUDABI_FILETYPE_SYMBOLIC_LINK; else csb.st_filetype = CLOUDABI_FILETYPE_UNKNOWN; return (copyout(&csb, uap->buf, sizeof(csb))); } int cloudabi_sys_file_stat_put(struct thread *td, struct cloudabi_sys_file_stat_put_args *uap) { cloudabi_filestat_t fs; struct timespec ts[2]; char *path; int error; /* * Only support timestamp modification for now, as there is no * truncateat(). */ if ((uap->flags & ~(CLOUDABI_FILESTAT_ATIM | CLOUDABI_FILESTAT_ATIM_NOW | CLOUDABI_FILESTAT_MTIM | CLOUDABI_FILESTAT_MTIM_NOW)) != 0) return (EINVAL); error = copyin(uap->buf, &fs, sizeof(fs)); if (error != 0) return (error); error = copyin_path(uap->path, uap->path_len, &path); if (error != 0) return (error); convert_utimens_arguments(&fs, uap->flags, ts); error = kern_utimensat(td, uap->fd.fd, path, UIO_SYSSPACE, ts, UIO_SYSSPACE, (uap->fd.flags & CLOUDABI_LOOKUP_SYMLINK_FOLLOW) ? 0 : AT_SYMLINK_NOFOLLOW); cloudabi_freestr(path); return (error); } int cloudabi_sys_file_symlink(struct thread *td, struct cloudabi_sys_file_symlink_args *uap) { char *path1, *path2; int error; error = copyin_path(uap->path1, uap->path1_len, &path1); if (error != 0) return (error); error = copyin_path(uap->path2, uap->path2_len, &path2); if (error != 0) { cloudabi_freestr(path1); return (error); } error = kern_symlinkat(td, path1, uap->fd, path2, UIO_SYSSPACE); cloudabi_freestr(path1); cloudabi_freestr(path2); return (error); } int cloudabi_sys_file_unlink(struct thread *td, struct cloudabi_sys_file_unlink_args *uap) { char *path; int error; error = copyin_path(uap->path, uap->path_len, &path); if (error != 0) return (error); if (uap->flags & CLOUDABI_UNLINK_REMOVEDIR) error = kern_rmdirat(td, uap->fd, path, UIO_SYSSPACE); else error = kern_unlinkat(td, uap->fd, path, UIO_SYSSPACE, 0); cloudabi_freestr(path); return (error); }