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xnu-4570.71.2.tar.gz
[apple/xnu.git] / bsd / kern / sys_pipe.c
index 374d82381f46dc38b56986ac68bf6a043e894dec..9e8b346e925615c09dfa09cc98555673b9b92c8e 100644 (file)
 #include <kern/kalloc.h>
 #include <vm/vm_kern.h>
 #include <libkern/OSAtomic.h>
+#include <libkern/section_keywords.h>
+
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#endif
 
 #define f_flag f_fglob->fg_flag
 #define f_msgcount f_fglob->fg_msgcount
  * interfaces to the outside world exported through file operations 
  */
 static int pipe_read(struct fileproc *fp, struct uio *uio,
-                int flags, vfs_context_t ctx);
+               int flags, vfs_context_t ctx);
 static int pipe_write(struct fileproc *fp, struct uio *uio,
-                int flags, vfs_context_t ctx);
+               int flags, vfs_context_t ctx);
 static int pipe_close(struct fileglob *fg, vfs_context_t ctx);
 static int pipe_select(struct fileproc *fp, int which, void * wql,
                vfs_context_t ctx);
 static int pipe_kqfilter(struct fileproc *fp, struct knote *kn,
-               vfs_context_t ctx);
+               struct kevent_internal_s *kev, vfs_context_t ctx);
 static int pipe_ioctl(struct fileproc *fp, u_long cmd, caddr_t data,
                vfs_context_t ctx);
 static int pipe_drain(struct fileproc *fp,vfs_context_t ctx);
 
 static const struct fileops pipeops = {
-       DTYPE_PIPE,
-       pipe_read,
-       pipe_write,
-       pipe_ioctl,
-       pipe_select,
-       pipe_close,
-       pipe_kqfilter,
-       pipe_drain
+       .fo_type = DTYPE_PIPE,
+       .fo_read = pipe_read,
+       .fo_write = pipe_write,
+       .fo_ioctl = pipe_ioctl,
+       .fo_select = pipe_select,
+       .fo_close = pipe_close,
+       .fo_kqfilter = pipe_kqfilter,
+       .fo_drain = pipe_drain,
 };
 
-static void    filt_pipedetach(struct knote *kn);
-static int     filt_piperead(struct knote *kn, long hint);
-static int     filt_pipewrite(struct knote *kn, long hint);
+static void filt_pipedetach(struct knote *kn);
 
-static struct filterops pipe_rfiltops = {
+static int filt_piperead(struct knote *kn, long hint);
+static int filt_pipereadtouch(struct knote *kn, struct kevent_internal_s *kev);
+static int filt_pipereadprocess(struct knote *kn, struct filt_process_s *data, struct kevent_internal_s *kev);
+
+static int filt_pipewrite(struct knote *kn, long hint);
+static int filt_pipewritetouch(struct knote *kn, struct kevent_internal_s *kev);
+static int filt_pipewriteprocess(struct knote *kn, struct filt_process_s *data, struct kevent_internal_s *kev);
+
+SECURITY_READ_ONLY_EARLY(struct filterops) pipe_rfiltops = {
         .f_isfd = 1,
         .f_detach = filt_pipedetach,
         .f_event = filt_piperead,
+       .f_touch = filt_pipereadtouch,
+       .f_process = filt_pipereadprocess,
 };
 
-static struct filterops pipe_wfiltops = {
+SECURITY_READ_ONLY_EARLY(struct filterops) pipe_wfiltops = {
         .f_isfd = 1,
         .f_detach = filt_pipedetach,
         .f_event = filt_pipewrite,
+       .f_touch = filt_pipewritetouch,
+       .f_process = filt_pipewriteprocess,
 };
 
 static int nbigpipe;      /* for compatibility sake. no longer used */
@@ -289,6 +304,7 @@ pipeinit(void)
        
 }
 
+#ifndef        CONFIG_EMBEDDED
 /* Bitmap for things to touch in pipe_touch() */
 #define        PIPE_ATIME      0x00000001      /* time of last access */
 #define        PIPE_MTIME      0x00000002      /* time of last modification */
@@ -297,27 +313,28 @@ pipeinit(void)
 static void
 pipe_touch(struct pipe *tpipe, int touch)
 {
-       struct timeval now;
+       struct timespec now;
 
-       microtime(&now);
+       nanotime(&now);
 
        if (touch & PIPE_ATIME) {
                tpipe->st_atimespec.tv_sec  = now.tv_sec;
-               tpipe->st_atimespec.tv_nsec = now.tv_usec * 1000;
+               tpipe->st_atimespec.tv_nsec = now.tv_nsec;
        }
 
        if (touch & PIPE_MTIME) {
                tpipe->st_mtimespec.tv_sec  = now.tv_sec;
-               tpipe->st_mtimespec.tv_nsec = now.tv_usec * 1000;
+               tpipe->st_mtimespec.tv_nsec = now.tv_nsec;
        }
 
        if (touch & PIPE_CTIME) {
                tpipe->st_ctimespec.tv_sec  = now.tv_sec;
-               tpipe->st_ctimespec.tv_nsec = now.tv_usec * 1000;
+               tpipe->st_ctimespec.tv_nsec = now.tv_nsec;
        }
 }
+#endif
 
-static const unsigned int pipesize_blocks[] = {128,256,1024,2048,4096, 4096 * 2, PIPE_SIZE , PIPE_SIZE * 4 };
+static const unsigned int pipesize_blocks[] = {512,1024,2048,4096, 4096 * 2, PIPE_SIZE , PIPE_SIZE * 4 };
 
 /* 
  * finds the right size from possible sizes in pipesize_blocks 
@@ -329,6 +346,12 @@ choose_pipespace(unsigned long current, unsigned long expected)
        int i = sizeof(pipesize_blocks)/sizeof(unsigned int) -1;
        unsigned long target;
 
+       /*
+        * assert that we always get an atomic transaction sized pipe buffer,
+        * even if the system pipe buffer high-water mark has been crossed.
+        */
+       assert(PIPE_BUF == pipesize_blocks[0]);
+
        if (expected > current) 
                target = expected;
        else
@@ -642,8 +665,10 @@ pipe_create(struct pipe **cpipep)
         */
        bzero(cpipe, sizeof *cpipe);
 
+#ifndef        CONFIG_EMBEDDED
        /* Initial times are all the time of creation of the pipe */
        pipe_touch(cpipe, PIPE_ATIME | PIPE_MTIME | PIPE_CTIME);
+#endif
        return (0);
 }
 
@@ -844,8 +869,10 @@ unlocked_error:
        if ((rpipe->pipe_buffer.size - rpipe->pipe_buffer.cnt) > 0)
                pipeselwakeup(rpipe, rpipe->pipe_peer);
 
+#ifndef        CONFIG_EMBEDDED
        /* update last read time */
        pipe_touch(rpipe, PIPE_ATIME);
+#endif
 
        PIPE_UNLOCK(rpipe);
 
@@ -1101,9 +1128,11 @@ pipe_write(struct fileproc *fp, struct uio *uio, __unused int flags,
                pipeselwakeup(wpipe, wpipe);
        }
 
+#ifndef        CONFIG_EMBEDDED
        /* Update modification, status change (# of bytes in pipe) times */
        pipe_touch(rpipe, PIPE_MTIME | PIPE_CTIME);
        pipe_touch(wpipe, PIPE_MTIME | PIPE_CTIME);
+#endif
        PIPE_UNLOCK(rpipe);
 
        return (error);
@@ -1353,11 +1382,178 @@ pipeclose(struct pipe *cpipe)
 
 /*ARGSUSED*/
 static int
-pipe_kqfilter(__unused struct fileproc *fp, struct knote *kn, __unused vfs_context_t ctx)
+filt_piperead_common(struct knote *kn, struct pipe *rpipe)
 {
-       struct pipe *cpipe;
+       struct pipe *wpipe;
+       int    retval;
+
+       /*
+        * we're being called back via the KNOTE post
+        * we made in pipeselwakeup, and we already hold the mutex...
+        */
+
+       wpipe = rpipe->pipe_peer;
+       kn->kn_data = rpipe->pipe_buffer.cnt;
+       if ((rpipe->pipe_state & (PIPE_DRAIN | PIPE_EOF)) ||
+           (wpipe == NULL) || (wpipe->pipe_state & (PIPE_DRAIN | PIPE_EOF))) {
+               kn->kn_flags |= EV_EOF;
+               retval = 1;
+       } else {
+               int64_t lowwat = 1;
+               if (kn->kn_sfflags & NOTE_LOWAT) {
+                       if (rpipe->pipe_buffer.size && kn->kn_sdata > MAX_PIPESIZE(rpipe))
+                               lowwat = MAX_PIPESIZE(rpipe);
+                       else if (kn->kn_sdata > lowwat)
+                               lowwat = kn->kn_sdata;
+               }
+               retval = kn->kn_data >= lowwat;
+       }
+       return (retval);
+}
+
+static int
+filt_piperead(struct knote *kn, long hint)
+{
+#pragma unused(hint)
+       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
+
+       return filt_piperead_common(kn, rpipe);
+}
+       
+static int
+filt_pipereadtouch(struct knote *kn, struct kevent_internal_s *kev)
+{
+       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
+       int retval;
+
+       PIPE_LOCK(rpipe);
+
+       /* accept new inputs (and save the low water threshold and flag) */
+       kn->kn_sdata = kev->data;
+       kn->kn_sfflags = kev->fflags;
+       if ((kn->kn_status & KN_UDATA_SPECIFIC) == 0)
+               kn->kn_udata = kev->udata;
+
+       /* identify if any events are now fired */
+       retval = filt_piperead_common(kn, rpipe);
+
+       PIPE_UNLOCK(rpipe);
+
+       return retval;
+}
+
+static int
+filt_pipereadprocess(struct knote *kn, struct filt_process_s *data, struct kevent_internal_s *kev)
+{
+#pragma unused(data)
+       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
+       int    retval;
+
+       PIPE_LOCK(rpipe);
+       retval = filt_piperead_common(kn, rpipe);
+       if (retval) {
+               *kev = kn->kn_kevent;
+               if (kn->kn_flags & EV_CLEAR) {
+                       kn->kn_fflags = 0;
+                       kn->kn_data = 0;
+               }
+       }
+       PIPE_UNLOCK(rpipe);
+
+       return (retval);
+}
+
+/*ARGSUSED*/
+static int
+filt_pipewrite_common(struct knote *kn, struct pipe *rpipe)
+{
+       struct pipe *wpipe;
+
+       /*
+        * we're being called back via the KNOTE post
+        * we made in pipeselwakeup, and we already hold the mutex...
+        */
+       wpipe = rpipe->pipe_peer;
+
+       if ((wpipe == NULL) || (wpipe->pipe_state & (PIPE_DRAIN | PIPE_EOF))) {
+               kn->kn_data = 0;
+               kn->kn_flags |= EV_EOF; 
+               return (1);
+       }
+       kn->kn_data = MAX_PIPESIZE(wpipe) - wpipe->pipe_buffer.cnt;
+
+       int64_t lowwat = PIPE_BUF;
+       if (kn->kn_sfflags & NOTE_LOWAT) {
+               if (wpipe->pipe_buffer.size && kn->kn_sdata > MAX_PIPESIZE(wpipe))
+                       lowwat = MAX_PIPESIZE(wpipe);
+               else if (kn->kn_sdata > lowwat)
+                       lowwat = kn->kn_sdata;
+       }
+
+       return (kn->kn_data >= lowwat);
+}
+
+/*ARGSUSED*/
+static int
+filt_pipewrite(struct knote *kn, long hint)
+{
+#pragma unused(hint)
+       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
+
+       return filt_pipewrite_common(kn, rpipe);
+}
+
+
+static int
+filt_pipewritetouch(struct knote *kn, struct kevent_internal_s *kev)
+{
+       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
+       int res;
+
+       PIPE_LOCK(rpipe);
+
+       /* accept new kevent data (and save off lowat threshold and flag) */
+       kn->kn_sfflags = kev->fflags;
+       kn->kn_sdata = kev->data;
+       if ((kn->kn_status & KN_UDATA_SPECIFIC) == 0)
+               kn->kn_udata = kev->udata;
+
+       /* determine if any event is now deemed fired */
+       res = filt_pipewrite_common(kn, rpipe);
+
+       PIPE_UNLOCK(rpipe);
+
+       return res;
+}
+
+static int
+filt_pipewriteprocess(struct knote *kn, struct filt_process_s *data, struct kevent_internal_s *kev)
+{
+#pragma unused(data)
+       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
+       int res;
+
+       PIPE_LOCK(rpipe);
+       res = filt_pipewrite_common(kn, rpipe);
+       if (res) {
+               *kev = kn->kn_kevent;
+               if (kn->kn_flags & EV_CLEAR) {
+                       kn->kn_fflags = 0;
+                       kn->kn_data = 0;
+               }
+       }
+       PIPE_UNLOCK(rpipe);
+
+       return res;
+}
 
-       cpipe = (struct pipe *)kn->kn_fp->f_data;
+/*ARGSUSED*/
+static int
+pipe_kqfilter(__unused struct fileproc *fp, struct knote *kn,
+               __unused struct kevent_internal_s *kev, __unused vfs_context_t ctx)
+{
+       struct pipe *cpipe = (struct pipe *)kn->kn_fp->f_data;
+       int res;
 
        PIPE_LOCK(cpipe);
 #if CONFIG_MACF
@@ -1368,38 +1564,50 @@ pipe_kqfilter(__unused struct fileproc *fp, struct knote *kn, __unused vfs_conte
         */
        if (mac_pipe_check_kqfilter(vfs_context_ucred(ctx), kn, cpipe) != 0) {
                PIPE_UNLOCK(cpipe);
-               return (1);
+               kn->kn_flags = EV_ERROR;
+               kn->kn_data = EPERM;
+               return 0;
        }
 #endif
 
        switch (kn->kn_filter) {
        case EVFILT_READ:
-               kn->kn_fop = &pipe_rfiltops;
+               kn->kn_filtid = EVFILTID_PIPE_R;
 
+               /* determine initial state */
+               res = filt_piperead_common(kn, cpipe);
                break;
+
        case EVFILT_WRITE:
-               kn->kn_fop = &pipe_wfiltops;
+               kn->kn_filtid = EVFILTID_PIPE_W;
 
                if (cpipe->pipe_peer == NULL) {
                        /*
                         * other end of pipe has been closed
                         */
                        PIPE_UNLOCK(cpipe);
-                       return (EPIPE);
+                       kn->kn_flags = EV_ERROR;
+                       kn->kn_data = EPIPE;
+                       return 0;
                }
                if (cpipe->pipe_peer)
                cpipe = cpipe->pipe_peer;
+
+               /* determine inital state */
+               res = filt_pipewrite_common(kn, cpipe);
                break;
        default:
                PIPE_UNLOCK(cpipe);
-               return (1);
+               kn->kn_flags = EV_ERROR;
+               kn->kn_data = EINVAL;
+               return 0;
        }
 
        if (KNOTE_ATTACH(&cpipe->pipe_sel.si_note, kn))
                cpipe->pipe_state |= PIPE_KNOTE;
 
        PIPE_UNLOCK(cpipe);
-       return (0);
+       return res;
 }
 
 static void
@@ -1423,95 +1631,13 @@ filt_pipedetach(struct knote *kn)
        PIPE_UNLOCK(cpipe);
 }
 
-/*ARGSUSED*/
-static int
-filt_piperead(struct knote *kn, long hint)
-{
-       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
-       struct pipe *wpipe;
-       int    retval;
-
-       /*
-        * if hint == 0, then we've been called from the kevent
-        * world directly and do not currently hold the pipe mutex...
-        * if hint == 1, we're being called back via the KNOTE post
-        * we made in pipeselwakeup, and we already hold the mutex...
-        */
-       if (hint == 0)
-               PIPE_LOCK(rpipe);
-
-       wpipe = rpipe->pipe_peer;
-       kn->kn_data = rpipe->pipe_buffer.cnt;
-       if ((rpipe->pipe_state & (PIPE_DRAIN | PIPE_EOF)) ||
-           (wpipe == NULL) || (wpipe->pipe_state & (PIPE_DRAIN | PIPE_EOF))) {
-               kn->kn_flags |= EV_EOF;
-               retval = 1;
-       } else {
-               int64_t lowwat = 1;
-               if (kn->kn_sfflags & NOTE_LOWAT) {
-                       if (rpipe->pipe_buffer.size && kn->kn_sdata > MAX_PIPESIZE(rpipe))
-                               lowwat = MAX_PIPESIZE(rpipe);
-                       else if (kn->kn_sdata > lowwat)
-                               lowwat = kn->kn_sdata;
-               }
-               retval = kn->kn_data >= lowwat;
-       }
-
-       if (hint == 0)
-               PIPE_UNLOCK(rpipe);
-
-       return (retval);
-}
-
-/*ARGSUSED*/
-static int
-filt_pipewrite(struct knote *kn, long hint)
-{
-       struct pipe *rpipe = (struct pipe *)kn->kn_fp->f_data;
-       struct pipe *wpipe;
-
-       /*
-        * if hint == 0, then we've been called from the kevent
-        * world directly and do not currently hold the pipe mutex...
-        * if hint == 1, we're being called back via the KNOTE post
-        * we made in pipeselwakeup, and we already hold the mutex...
-        */
-       if (hint == 0)
-               PIPE_LOCK(rpipe);
-
-       wpipe = rpipe->pipe_peer;
-
-       if ((wpipe == NULL) || (wpipe->pipe_state & (PIPE_DRAIN | PIPE_EOF))) {
-               kn->kn_data = 0;
-               kn->kn_flags |= EV_EOF; 
-
-               if (hint == 0)
-                       PIPE_UNLOCK(rpipe);
-               return (1);
-       }
-       kn->kn_data = MAX_PIPESIZE(wpipe) - wpipe->pipe_buffer.cnt;
-
-       int64_t lowwat = PIPE_BUF;
-       if (kn->kn_sfflags & NOTE_LOWAT) {
-               if (wpipe->pipe_buffer.size && kn->kn_sdata > MAX_PIPESIZE(wpipe))
-                       lowwat = MAX_PIPESIZE(wpipe);
-               else if (kn->kn_sdata > lowwat)
-                       lowwat = kn->kn_sdata;
-       }
-       
-       if (hint == 0)
-               PIPE_UNLOCK(rpipe);
-
-       return (kn->kn_data >= lowwat);
-}
-
 int
 fill_pipeinfo(struct pipe * cpipe, struct pipe_info * pinfo)
 {
 #if CONFIG_MACF
         int error;
 #endif
-       struct timeval now;
+       struct timespec now;
        struct vinfo_stat * ub;
        int pipe_size = 0;
        int pipe_count;
@@ -1564,15 +1690,15 @@ fill_pipeinfo(struct pipe * cpipe, struct pipe_info * pinfo)
        ub->vst_uid = kauth_getuid();
        ub->vst_gid = kauth_getgid();
 
-       microtime(&now);
+       nanotime(&now);
        ub->vst_atime  = now.tv_sec;
-       ub->vst_atimensec = now.tv_usec * 1000;
+       ub->vst_atimensec = now.tv_nsec;
 
        ub->vst_mtime  = now.tv_sec;
-       ub->vst_mtimensec = now.tv_usec * 1000;
+       ub->vst_mtimensec = now.tv_nsec;
 
        ub->vst_ctime  = now.tv_sec;
-       ub->vst_ctimensec = now.tv_usec * 1000;
+       ub->vst_ctimensec = now.tv_nsec;
 
        /*
         * Left as 0: st_dev, st_ino, st_nlink, st_rdev, st_flags, st_gen, st_uid, st_gid.