Author: ed Date: Wed Jul 29 17:18:27 2015 New Revision: 286021 URL: https://svnweb.freebsd.org/changeset/base/286021
Log: Make pipes in CloudABI work. Summary: Pipes in CloudABI are unidirectional. The reason for this is that CloudABI attempts to provide a uniform runtime environment across different flavours of UNIX. Instead of implementing a custom pipe that is unidirectional, we can simply reuse Capsicum permission bits to support this. This is nice, because CloudABI already attempts to restrict permission bits to correspond with the operations that apply to a certain file descriptor. Replace kern_pipe() and kern_pipe2() by a single kern_pipe() that takes a pair of filecaps. These filecaps are passed to the newly introduced falloc_caps() function that creates the descriptors with rights in place. Test Plan: CloudABI pipes seem to be created with proper rights in place: https://github.com/NuxiNL/cloudlibc/blob/master/src/libc/unistd/pipe_test.c#L44 Reviewers: jilles, mjg Reviewed By: mjg Subscribers: imp Differential Revision: https://reviews.freebsd.org/D3236 Modified: head/sys/compat/cloudabi/cloudabi_fd.c head/sys/compat/linux/linux_file.c head/sys/kern/sys_pipe.c head/sys/sys/syscallsubr.h Modified: head/sys/compat/cloudabi/cloudabi_fd.c ============================================================================== --- head/sys/compat/cloudabi/cloudabi_fd.c Wed Jul 29 17:16:53 2015 (r286020) +++ head/sys/compat/cloudabi/cloudabi_fd.c Wed Jul 29 17:18:27 2015 (r286021) @@ -120,10 +120,24 @@ int cloudabi_sys_fd_create2(struct thread *td, struct cloudabi_sys_fd_create2_args *uap) { + struct filecaps fcaps1 = {}, fcaps2 = {}; int fds[2]; int error; switch (uap->type) { + case CLOUDABI_FILETYPE_FIFO: + /* + * CloudABI pipes are unidirectional. Restrict rights on + * the pipe to simulate this. + */ + cap_rights_init(&fcaps1.fc_rights, CAP_EVENT, CAP_FCNTL, + CAP_FSTAT, CAP_READ); + fcaps1.fc_fcntls = CAP_FCNTL_SETFL; + cap_rights_init(&fcaps2.fc_rights, CAP_EVENT, CAP_FCNTL, + CAP_FSTAT, CAP_WRITE); + fcaps2.fc_fcntls = CAP_FCNTL_SETFL; + error = kern_pipe(td, fds, 0, &fcaps1, &fcaps2); + break; case CLOUDABI_FILETYPE_SOCKET_DGRAM: error = kern_socketpair(td, AF_UNIX, SOCK_DGRAM, 0, fds); break; Modified: head/sys/compat/linux/linux_file.c ============================================================================== --- head/sys/compat/linux/linux_file.c Wed Jul 29 17:16:53 2015 (r286020) +++ head/sys/compat/linux/linux_file.c Wed Jul 29 17:18:27 2015 (r286021) @@ -1582,7 +1582,7 @@ linux_pipe(struct thread *td, struct lin printf(ARGS(pipe, "*")); #endif - error = kern_pipe2(td, fildes, 0); + error = kern_pipe(td, fildes, 0, NULL, NULL); if (error) return (error); @@ -1609,7 +1609,7 @@ linux_pipe2(struct thread *td, struct li flags |= O_NONBLOCK; if ((args->flags & LINUX_O_CLOEXEC) != 0) flags |= O_CLOEXEC; - error = kern_pipe2(td, fildes, flags); + error = kern_pipe(td, fildes, flags, NULL, NULL); if (error) return (error); Modified: head/sys/kern/sys_pipe.c ============================================================================== --- head/sys/kern/sys_pipe.c Wed Jul 29 17:16:53 2015 (r286020) +++ head/sys/kern/sys_pipe.c Wed Jul 29 17:18:27 2015 (r286021) @@ -397,14 +397,8 @@ pipe_dtor(struct pipe *dpipe) * the zone pick up the pieces via pipeclose(). */ int -kern_pipe(struct thread *td, int fildes[2]) -{ - - return (kern_pipe2(td, fildes, 0)); -} - -int -kern_pipe2(struct thread *td, int fildes[2], int flags) +kern_pipe(struct thread *td, int fildes[2], int flags, struct filecaps *fcaps1, + struct filecaps *fcaps2) { struct file *rf, *wf; struct pipe *rpipe, *wpipe; @@ -414,13 +408,13 @@ kern_pipe2(struct thread *td, int fildes pipe_paircreate(td, &pp); rpipe = &pp->pp_rpipe; wpipe = &pp->pp_wpipe; - error = falloc(td, &rf, &fd, flags); + error = falloc_caps(td, &rf, &fd, flags, fcaps1); if (error) { pipeclose(rpipe); pipeclose(wpipe); return (error); } - /* An extra reference on `rf' has been held for us by falloc(). */ + /* An extra reference on `rf' has been held for us by falloc_caps(). */ fildes[0] = fd; fflags = FREAD | FWRITE; @@ -434,7 +428,7 @@ kern_pipe2(struct thread *td, int fildes * side while we are blocked trying to allocate the write side. */ finit(rf, fflags, DTYPE_PIPE, rpipe, &pipeops); - error = falloc(td, &wf, &fd, flags); + error = falloc_caps(td, &wf, &fd, flags, fcaps2); if (error) { fdclose(td, rf, fildes[0]); fdrop(rf, td); @@ -442,7 +436,7 @@ kern_pipe2(struct thread *td, int fildes pipeclose(wpipe); return (error); } - /* An extra reference on `wf' has been held for us by falloc(). */ + /* An extra reference on `wf' has been held for us by falloc_caps(). */ finit(wf, fflags, DTYPE_PIPE, wpipe, &pipeops); fdrop(wf, td); fildes[1] = fd; @@ -458,7 +452,7 @@ sys_pipe(struct thread *td, struct pipe_ int error; int fildes[2]; - error = kern_pipe(td, fildes); + error = kern_pipe(td, fildes, 0, NULL, NULL); if (error) return (error); @@ -475,7 +469,7 @@ sys_pipe2(struct thread *td, struct pipe if (uap->flags & ~(O_CLOEXEC | O_NONBLOCK)) return (EINVAL); - error = kern_pipe2(td, fildes, uap->flags); + error = kern_pipe(td, fildes, uap->flags, NULL, NULL); if (error) return (error); error = copyout(fildes, uap->fildes, 2 * sizeof(int)); Modified: head/sys/sys/syscallsubr.h ============================================================================== --- head/sys/sys/syscallsubr.h Wed Jul 29 17:16:53 2015 (r286020) +++ head/sys/sys/syscallsubr.h Wed Jul 29 17:18:27 2015 (r286021) @@ -35,6 +35,7 @@ #include <sys/mount.h> struct file; +struct filecaps; enum idtype; struct itimerval; struct image_args; @@ -150,8 +151,8 @@ int kern_openat(struct thread *td, int f enum uio_seg pathseg, int flags, int mode); int kern_pathconf(struct thread *td, char *path, enum uio_seg pathseg, int name, u_long flags); -int kern_pipe(struct thread *td, int fildes[2]); -int kern_pipe2(struct thread *td, int fildes[2], int flags); +int kern_pipe(struct thread *td, int fildes[2], int flags, + struct filecaps *fcaps1, struct filecaps *fcaps2); int kern_poll(struct thread *td, struct pollfd *fds, u_int nfds, struct timespec *tsp, sigset_t *uset); int kern_posix_fadvise(struct thread *td, int fd, off_t offset, off_t len, _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
