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Registered in England and Wales under Company Registration No. 3798903 Subject: [RFC PATCH 07/14] Add sample notification program [ver #2] From: David Howells To: torvalds@linux-foundation.org Cc: dhowells@redhat.com, Greg Kroah-Hartman , Casey Schaufler , Stephen Smalley , nicolas.dichtel@6wind.com, raven@themaw.net, Christian Brauner , dhowells@redhat.com, keyrings@vger.kernel.org, linux-usb@vger.kernel.org, linux-block@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 07 Nov 2019 13:36:24 +0000 Message-ID: <157313378451.29677.3803723365602483685.stgit@warthog.procyon.org.uk> In-Reply-To: <157313371694.29677.15388731274912671071.stgit@warthog.procyon.org.uk> References: <157313371694.29677.15388731274912671071.stgit@warthog.procyon.org.uk> User-Agent: StGit/unknown-version MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: wDIB_NiyOzigshJxDwFdSA-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org The sample program is run like: =09./samples/watch_queue/watch_test and watches "/" for mount changes and the current session keyring for key changes: =09# keyctl add user a a @s =091035096409 =09# keyctl unlink 1035096409 @s producing: =09# ./watch_test =09read() =3D 16 =09NOTIFY[000]: ty=3D000001 sy=3D02 i=3D00000110 =09KEY 2ffc2e5d change=3D2[linked] aux=3D1035096409 =09read() =3D 16 =09NOTIFY[000]: ty=3D000001 sy=3D02 i=3D00000110 =09KEY 2ffc2e5d change=3D3[unlinked] aux=3D1035096409 Other events may be produced, such as with a failing disk: =09read() =3D 22 =09NOTIFY[000]: ty=3D000003 sy=3D02 i=3D00000416 =09USB 3-7.7 dev-reset e=3D0 r=3D0 =09read() =3D 24 =09NOTIFY[000]: ty=3D000002 sy=3D06 i=3D00000418 =09BLOCK 00800050 e=3D6[critical medium] s=3D64000ef8 This corresponds to: =09blk_update_request: critical medium error, dev sdf, sector 1677725432 op= 0x0:(READ) flags 0x0 phys_seg 1 prio class 0 in dmesg. Signed-off-by: David Howells --- samples/Kconfig | 7 + samples/Makefile | 1=20 samples/watch_queue/Makefile | 7 + samples/watch_queue/watch_test.c | 183 ++++++++++++++++++++++++++++++++++= ++++ 4 files changed, 198 insertions(+) create mode 100644 samples/watch_queue/Makefile create mode 100644 samples/watch_queue/watch_test.c diff --git a/samples/Kconfig b/samples/Kconfig index c8dacb4dda80..d0761f29ccb0 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -169,4 +169,11 @@ config SAMPLE_VFS =09 as mount API and statx(). Note that this is restricted to the x86 =09 arch whilst it accesses system calls that aren't yet in all arches. =20 +config SAMPLE_WATCH_QUEUE +=09bool "Build example /dev/watch_queue notification consumer" +=09depends on HEADERS_INSTALL +=09help +=09 Build example userspace program to use the new mount_notify(), +=09 sb_notify() syscalls and the KEYCTL_WATCH_KEY keyctl() function. + endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index 7d6e4ca28d69..a61a39047d02 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -20,3 +20,4 @@ obj-$(CONFIG_SAMPLE_TRACE_PRINTK)=09+=3D trace_printk/ obj-$(CONFIG_VIDEO_PCI_SKELETON)=09+=3D v4l/ obj-y=09=09=09=09=09+=3D vfio-mdev/ subdir-$(CONFIG_SAMPLE_VFS)=09=09+=3D vfs +subdir-$(CONFIG_SAMPLE_WATCH_QUEUE)=09+=3D watch_queue diff --git a/samples/watch_queue/Makefile b/samples/watch_queue/Makefile new file mode 100644 index 000000000000..eec00dd0a8df --- /dev/null +++ b/samples/watch_queue/Makefile @@ -0,0 +1,7 @@ +# List of programs to build +hostprogs-y :=3D watch_test + +# Tell kbuild to always build the programs +always :=3D $(hostprogs-y) + +HOSTCFLAGS_watch_test.o +=3D -I$(objtree)/usr/include diff --git a/samples/watch_queue/watch_test.c b/samples/watch_queue/watch_t= est.c new file mode 100644 index 000000000000..8925593bdb9b --- /dev/null +++ b/samples/watch_queue/watch_test.c @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Use /dev/watch_queue to watch for notifications. + * + * Copyright (C) 2019 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifndef KEYCTL_WATCH_KEY +#define KEYCTL_WATCH_KEY -1 +#endif +#ifndef __NR_watch_devices +#define __NR_watch_devices -1 +#endif + +#define BUF_SIZE 256 + +static long keyctl_watch_key(int key, int watch_fd, int watch_id) +{ +=09return syscall(__NR_keyctl, KEYCTL_WATCH_KEY, key, watch_fd, watch_id); +} + +static const char *key_subtypes[256] =3D { +=09[NOTIFY_KEY_INSTANTIATED]=09=3D "instantiated", +=09[NOTIFY_KEY_UPDATED]=09=09=3D "updated", +=09[NOTIFY_KEY_LINKED]=09=09=3D "linked", +=09[NOTIFY_KEY_UNLINKED]=09=09=3D "unlinked", +=09[NOTIFY_KEY_CLEARED]=09=09=3D "cleared", +=09[NOTIFY_KEY_REVOKED]=09=09=3D "revoked", +=09[NOTIFY_KEY_INVALIDATED]=09=3D "invalidated", +=09[NOTIFY_KEY_SETATTR]=09=09=3D "setattr", +}; + +static void saw_key_change(struct watch_notification *n, size_t len) +{ +=09struct key_notification *k =3D (struct key_notification *)n; + +=09if (len !=3D sizeof(struct key_notification)) { +=09=09fprintf(stderr, "Incorrect key message length\n"); +=09=09return; +=09} + +=09printf("KEY %08x change=3D%u[%s] aux=3D%u\n", +=09 k->key_id, n->subtype, key_subtypes[n->subtype], k->aux); +} + +/* + * Consume and display events. + */ +static void consumer(int fd) +{ +=09unsigned char buffer[4096], *p, *end; +=09union { +=09=09struct watch_notification n; +=09=09unsigned char buf1[128]; +=09} n; +=09ssize_t buf_len; + +=09for (;;) { +=09=09buf_len =3D read(fd, buffer, sizeof(buffer)); +=09=09if (buf_len =3D=3D -1) { +=09=09=09perror("read"); +=09=09=09exit(1); +=09=09} + +=09=09if (buf_len =3D=3D 0) { +=09=09=09printf("-- END --\n"); +=09=09=09return; +=09=09} + +=09=09if (buf_len > sizeof(buffer)) { +=09=09=09fprintf(stderr, "Read buffer overrun: %zd\n", buf_len); +=09=09=09return; +=09=09} + +=09=09printf("read() =3D %zd\n", buf_len); + +=09=09p =3D buffer; +=09=09end =3D buffer + buf_len; +=09=09while (p < end) { +=09=09=09size_t largest, len; + +=09=09=09largest =3D end - p; +=09=09=09if (largest > 128) +=09=09=09=09largest =3D 128; +=09=09=09if (largest < sizeof(struct watch_notification)) { +=09=09=09=09fprintf(stderr, "Short message header: %zu\n", largest); +=09=09=09=09return; +=09=09=09} +=09=09=09memcpy(&n, p, largest); + +=09=09=09printf("NOTIFY[%03zx]: ty=3D%06x sy=3D%02x i=3D%08x\n", +=09=09=09 p - buffer, n.n.type, n.n.subtype, n.n.info); + +=09=09=09len =3D n.n.info & WATCH_INFO_LENGTH; +=09=09=09if (len < sizeof(n.n) || len > largest) { +=09=09=09=09fprintf(stderr, "Bad message length: %zu/%zu\n", len, largest)= ; +=09=09=09=09exit(1); +=09=09=09} + +=09=09=09switch (n.n.type) { +=09=09=09case WATCH_TYPE_META: +=09=09=09=09switch (n.n.subtype) { +=09=09=09=09case WATCH_META_REMOVAL_NOTIFICATION: +=09=09=09=09=09printf("REMOVAL of watchpoint %08x\n", +=09=09=09=09=09 (n.n.info & WATCH_INFO_ID) >> +=09=09=09=09=09 WATCH_INFO_ID__SHIFT); +=09=09=09=09=09break; +=09=09=09=09default: +=09=09=09=09=09printf("other meta record\n"); +=09=09=09=09=09break; +=09=09=09=09} +=09=09=09=09break; +=09=09=09case WATCH_TYPE_KEY_NOTIFY: +=09=09=09=09saw_key_change(&n.n, len); +=09=09=09=09break; +=09=09=09default: +=09=09=09=09printf("other type\n"); +=09=09=09=09break; +=09=09=09} + +=09=09=09p +=3D len; +=09=09} +=09} +} + +static struct watch_notification_filter filter =3D { +=09.nr_filters=09=3D 1, +=09.filters =3D { +=09=09[0]=09=3D { +=09=09=09.type=09=09=09=3D WATCH_TYPE_KEY_NOTIFY, +=09=09=09.subtype_filter[0]=09=3D UINT_MAX, +=09=09}, +=09}, +}; + +int main(int argc, char **argv) +{ +=09int pipefd[2], fd; + +=09if (pipe2(pipefd, O_NOTIFICATION_PIPE) =3D=3D -1) { +=09=09perror("pipe2"); +=09=09exit(1); +=09} +=09fd =3D pipefd[0]; + +=09if (ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, BUF_SIZE) =3D=3D -1) { +=09=09perror("/dev/watch_queue(size)"); +=09=09exit(1); +=09} + +=09if (ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter) =3D=3D -1) { +=09=09perror("/dev/watch_queue(filter)"); +=09=09exit(1); +=09} + +=09if (keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fd, 0x01) =3D=3D -1) { +=09=09perror("keyctl"); +=09=09exit(1); +=09} + +=09if (keyctl_watch_key(KEY_SPEC_USER_KEYRING, fd, 0x02) =3D=3D -1) { +=09=09perror("keyctl"); +=09=09exit(1); +=09} + +=09consumer(fd); +=09exit(0); +} From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Date: Thu, 07 Nov 2019 13:36:24 +0000 Subject: [RFC PATCH 07/14] Add sample notification program [ver #2] Message-Id: <157313378451.29677.3803723365602483685.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit List-Id: References: <157313371694.29677.15388731274912671071.stgit@warthog.procyon.org.uk> In-Reply-To: <157313371694.29677.15388731274912671071.stgit@warthog.procyon.org.uk> To: torvalds@linux-foundation.org Cc: dhowells@redhat.com, Greg Kroah-Hartman , Casey Schaufler , Stephen Smalley , nicolas.dichtel@6wind.com, raven@themaw.net, Christian Brauner dhowells@redhat.com, keyrings@vger.kernel.org, linux-usb@vger.kernel.org, linux-block@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org@vger.kernel.org, linux-kernel@vger.kernel.org The sample program is run like: ./samples/watch_queue/watch_test and watches "/" for mount changes and the current session keyring for key changes: # keyctl add user a a @s 1035096409 # keyctl unlink 1035096409 @s producing: # ./watch_test read() = 16 NOTIFY[000]: ty=000001 sy=02 i=00000110 KEY 2ffc2e5d change=2[linked] aux=1035096409 read() = 16 NOTIFY[000]: ty=000001 sy=02 i=00000110 KEY 2ffc2e5d change=3[unlinked] aux=1035096409 Other events may be produced, such as with a failing disk: read() = 22 NOTIFY[000]: ty=000003 sy=02 i=00000416 USB 3-7.7 dev-reset e=0 r=0 read() = 24 NOTIFY[000]: ty=000002 sy=06 i=00000418 BLOCK 00800050 e=6[critical medium] s=64000ef8 This corresponds to: blk_update_request: critical medium error, dev sdf, sector 1677725432 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0 in dmesg. Signed-off-by: David Howells --- samples/Kconfig | 7 + samples/Makefile | 1 samples/watch_queue/Makefile | 7 + samples/watch_queue/watch_test.c | 183 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 198 insertions(+) create mode 100644 samples/watch_queue/Makefile create mode 100644 samples/watch_queue/watch_test.c diff --git a/samples/Kconfig b/samples/Kconfig index c8dacb4dda80..d0761f29ccb0 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -169,4 +169,11 @@ config SAMPLE_VFS as mount API and statx(). Note that this is restricted to the x86 arch whilst it accesses system calls that aren't yet in all arches. +config SAMPLE_WATCH_QUEUE + bool "Build example /dev/watch_queue notification consumer" + depends on HEADERS_INSTALL + help + Build example userspace program to use the new mount_notify(), + sb_notify() syscalls and the KEYCTL_WATCH_KEY keyctl() function. + endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index 7d6e4ca28d69..a61a39047d02 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -20,3 +20,4 @@ obj-$(CONFIG_SAMPLE_TRACE_PRINTK) += trace_printk/ obj-$(CONFIG_VIDEO_PCI_SKELETON) += v4l/ obj-y += vfio-mdev/ subdir-$(CONFIG_SAMPLE_VFS) += vfs +subdir-$(CONFIG_SAMPLE_WATCH_QUEUE) += watch_queue diff --git a/samples/watch_queue/Makefile b/samples/watch_queue/Makefile new file mode 100644 index 000000000000..eec00dd0a8df --- /dev/null +++ b/samples/watch_queue/Makefile @@ -0,0 +1,7 @@ +# List of programs to build +hostprogs-y := watch_test + +# Tell kbuild to always build the programs +always := $(hostprogs-y) + +HOSTCFLAGS_watch_test.o += -I$(objtree)/usr/include diff --git a/samples/watch_queue/watch_test.c b/samples/watch_queue/watch_test.c new file mode 100644 index 000000000000..8925593bdb9b --- /dev/null +++ b/samples/watch_queue/watch_test.c @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Use /dev/watch_queue to watch for notifications. + * + * Copyright (C) 2019 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifndef KEYCTL_WATCH_KEY +#define KEYCTL_WATCH_KEY -1 +#endif +#ifndef __NR_watch_devices +#define __NR_watch_devices -1 +#endif + +#define BUF_SIZE 256 + +static long keyctl_watch_key(int key, int watch_fd, int watch_id) +{ + return syscall(__NR_keyctl, KEYCTL_WATCH_KEY, key, watch_fd, watch_id); +} + +static const char *key_subtypes[256] = { + [NOTIFY_KEY_INSTANTIATED] = "instantiated", + [NOTIFY_KEY_UPDATED] = "updated", + [NOTIFY_KEY_LINKED] = "linked", + [NOTIFY_KEY_UNLINKED] = "unlinked", + [NOTIFY_KEY_CLEARED] = "cleared", + [NOTIFY_KEY_REVOKED] = "revoked", + [NOTIFY_KEY_INVALIDATED] = "invalidated", + [NOTIFY_KEY_SETATTR] = "setattr", +}; + +static void saw_key_change(struct watch_notification *n, size_t len) +{ + struct key_notification *k = (struct key_notification *)n; + + if (len != sizeof(struct key_notification)) { + fprintf(stderr, "Incorrect key message length\n"); + return; + } + + printf("KEY %08x change=%u[%s] aux=%u\n", + k->key_id, n->subtype, key_subtypes[n->subtype], k->aux); +} + +/* + * Consume and display events. + */ +static void consumer(int fd) +{ + unsigned char buffer[4096], *p, *end; + union { + struct watch_notification n; + unsigned char buf1[128]; + } n; + ssize_t buf_len; + + for (;;) { + buf_len = read(fd, buffer, sizeof(buffer)); + if (buf_len == -1) { + perror("read"); + exit(1); + } + + if (buf_len == 0) { + printf("-- END --\n"); + return; + } + + if (buf_len > sizeof(buffer)) { + fprintf(stderr, "Read buffer overrun: %zd\n", buf_len); + return; + } + + printf("read() = %zd\n", buf_len); + + p = buffer; + end = buffer + buf_len; + while (p < end) { + size_t largest, len; + + largest = end - p; + if (largest > 128) + largest = 128; + if (largest < sizeof(struct watch_notification)) { + fprintf(stderr, "Short message header: %zu\n", largest); + return; + } + memcpy(&n, p, largest); + + printf("NOTIFY[%03zx]: ty=%06x sy=%02x i=%08x\n", + p - buffer, n.n.type, n.n.subtype, n.n.info); + + len = n.n.info & WATCH_INFO_LENGTH; + if (len < sizeof(n.n) || len > largest) { + fprintf(stderr, "Bad message length: %zu/%zu\n", len, largest); + exit(1); + } + + switch (n.n.type) { + case WATCH_TYPE_META: + switch (n.n.subtype) { + case WATCH_META_REMOVAL_NOTIFICATION: + printf("REMOVAL of watchpoint %08x\n", + (n.n.info & WATCH_INFO_ID) >> + WATCH_INFO_ID__SHIFT); + break; + default: + printf("other meta record\n"); + break; + } + break; + case WATCH_TYPE_KEY_NOTIFY: + saw_key_change(&n.n, len); + break; + default: + printf("other type\n"); + break; + } + + p += len; + } + } +} + +static struct watch_notification_filter filter = { + .nr_filters = 1, + .filters = { + [0] = { + .type = WATCH_TYPE_KEY_NOTIFY, + .subtype_filter[0] = UINT_MAX, + }, + }, +}; + +int main(int argc, char **argv) +{ + int pipefd[2], fd; + + if (pipe2(pipefd, O_NOTIFICATION_PIPE) == -1) { + perror("pipe2"); + exit(1); + } + fd = pipefd[0]; + + if (ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, BUF_SIZE) == -1) { + perror("/dev/watch_queue(size)"); + exit(1); + } + + if (ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter) == -1) { + perror("/dev/watch_queue(filter)"); + exit(1); + } + + if (keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fd, 0x01) == -1) { + perror("keyctl"); + exit(1); + } + + if (keyctl_watch_key(KEY_SPEC_USER_KEYRING, fd, 0x02) == -1) { + perror("keyctl"); + exit(1); + } + + consumer(fd); + exit(0); +} From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Subject: [RFC PATCH 07/14] Add sample notification program [ver #2] Date: Thu, 07 Nov 2019 13:36:24 +0000 Message-ID: <157313378451.29677.3803723365602483685.stgit@warthog.procyon.org.uk> References: <157313371694.29677.15388731274912671071.stgit@warthog.procyon.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <157313371694.29677.15388731274912671071.stgit@warthog.procyon.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: torvalds@linux-foundation.org Cc: dhowells@redhat.com, Greg Kroah-Hartman , Casey Schaufler , Stephen Smalley , nicolas.dichtel@6wind.com, raven@themaw.net, Christian Brauner dhowells@redhat.com, keyrings@vger.kernel.org, linux-usb@vger.kernel.org, linux-block@vger.kernel.org, linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.orglinux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-api@vger.kernel.org The sample program is run like: =09./samples/watch_queue/watch_test and watches "/" for mount changes and the current session keyring for key changes: =09# keyctl add user a a @s =091035096409 =09# keyctl unlink 1035096409 @s producing: =09# ./watch_test =09read() =3D 16 =09NOTIFY[000]: ty=3D000001 sy=3D02 i=3D00000110 =09KEY 2ffc2e5d change=3D2[linked] aux=3D1035096409 =09read() =3D 16 =09NOTIFY[000]: ty=3D000001 sy=3D02 i=3D00000110 =09KEY 2ffc2e5d change=3D3[unlinked] aux=3D1035096409 Other events may be produced, such as with a failing disk: =09read() =3D 22 =09NOTIFY[000]: ty=3D000003 sy=3D02 i=3D00000416 =09USB 3-7.7 dev-reset e=3D0 r=3D0 =09read() =3D 24 =09NOTIFY[000]: ty=3D000002 sy=3D06 i=3D00000418 =09BLOCK 00800050 e=3D6[critical medium] s=3D64000ef8 This corresponds to: =09blk_update_request: critical medium error, dev sdf, sector 1677725432 op= 0x0:(READ) flags 0x0 phys_seg 1 prio class 0 in dmesg. Signed-off-by: David Howells --- samples/Kconfig | 7 + samples/Makefile | 1=20 samples/watch_queue/Makefile | 7 + samples/watch_queue/watch_test.c | 183 ++++++++++++++++++++++++++++++++++= ++++ 4 files changed, 198 insertions(+) create mode 100644 samples/watch_queue/Makefile create mode 100644 samples/watch_queue/watch_test.c diff --git a/samples/Kconfig b/samples/Kconfig index c8dacb4dda80..d0761f29ccb0 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -169,4 +169,11 @@ config SAMPLE_VFS =09 as mount API and statx(). Note that this is restricted to the x86 =09 arch whilst it accesses system calls that aren't yet in all arches. =20 +config SAMPLE_WATCH_QUEUE +=09bool "Build example /dev/watch_queue notification consumer" +=09depends on HEADERS_INSTALL +=09help +=09 Build example userspace program to use the new mount_notify(), +=09 sb_notify() syscalls and the KEYCTL_WATCH_KEY keyctl() function. + endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index 7d6e4ca28d69..a61a39047d02 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -20,3 +20,4 @@ obj-$(CONFIG_SAMPLE_TRACE_PRINTK)=09+=3D trace_printk/ obj-$(CONFIG_VIDEO_PCI_SKELETON)=09+=3D v4l/ obj-y=09=09=09=09=09+=3D vfio-mdev/ subdir-$(CONFIG_SAMPLE_VFS)=09=09+=3D vfs +subdir-$(CONFIG_SAMPLE_WATCH_QUEUE)=09+=3D watch_queue diff --git a/samples/watch_queue/Makefile b/samples/watch_queue/Makefile new file mode 100644 index 000000000000..eec00dd0a8df --- /dev/null +++ b/samples/watch_queue/Makefile @@ -0,0 +1,7 @@ +# List of programs to build +hostprogs-y :=3D watch_test + +# Tell kbuild to always build the programs +always :=3D $(hostprogs-y) + +HOSTCFLAGS_watch_test.o +=3D -I$(objtree)/usr/include diff --git a/samples/watch_queue/watch_test.c b/samples/watch_queue/watch_t= est.c new file mode 100644 index 000000000000..8925593bdb9b --- /dev/null +++ b/samples/watch_queue/watch_test.c @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Use /dev/watch_queue to watch for notifications. + * + * Copyright (C) 2019 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifndef KEYCTL_WATCH_KEY +#define KEYCTL_WATCH_KEY -1 +#endif +#ifndef __NR_watch_devices +#define __NR_watch_devices -1 +#endif + +#define BUF_SIZE 256 + +static long keyctl_watch_key(int key, int watch_fd, int watch_id) +{ +=09return syscall(__NR_keyctl, KEYCTL_WATCH_KEY, key, watch_fd, watch_id); +} + +static const char *key_subtypes[256] =3D { +=09[NOTIFY_KEY_INSTANTIATED]=09=3D "instantiated", +=09[NOTIFY_KEY_UPDATED]=09=09=3D "updated", +=09[NOTIFY_KEY_LINKED]=09=09=3D "linked", +=09[NOTIFY_KEY_UNLINKED]=09=09=3D "unlinked", +=09[NOTIFY_KEY_CLEARED]=09=09=3D "cleared", +=09[NOTIFY_KEY_REVOKED]=09=09=3D "revoked", +=09[NOTIFY_KEY_INVALIDATED]=09=3D "invalidated", +=09[NOTIFY_KEY_SETATTR]=09=09=3D "setattr", +}; + +static void saw_key_change(struct watch_notification *n, size_t len) +{ +=09struct key_notification *k =3D (struct key_notification *)n; + +=09if (len !=3D sizeof(struct key_notification)) { +=09=09fprintf(stderr, "Incorrect key message length\n"); +=09=09return; +=09} + +=09printf("KEY %08x change=3D%u[%s] aux=3D%u\n", +=09 k->key_id, n->subtype, key_subtypes[n->subtype], k->aux); +} + +/* + * Consume and display events. + */ +static void consumer(int fd) +{ +=09unsigned char buffer[4096], *p, *end; +=09union { +=09=09struct watch_notification n; +=09=09unsigned char buf1[128]; +=09} n; +=09ssize_t buf_len; + +=09for (;;) { +=09=09buf_len =3D read(fd, buffer, sizeof(buffer)); +=09=09if (buf_len =3D=3D -1) { +=09=09=09perror("read"); +=09=09=09exit(1); +=09=09} + +=09=09if (buf_len =3D=3D 0) { +=09=09=09printf("-- END --\n"); +=09=09=09return; +=09=09} + +=09=09if (buf_len > sizeof(buffer)) { +=09=09=09fprintf(stderr, "Read buffer overrun: %zd\n", buf_len); +=09=09=09return; +=09=09} + +=09=09printf("read() =3D %zd\n", buf_len); + +=09=09p =3D buffer; +=09=09end =3D buffer + buf_len; +=09=09while (p < end) { +=09=09=09size_t largest, len; + +=09=09=09largest =3D end - p; +=09=09=09if (largest > 128) +=09=09=09=09largest =3D 128; +=09=09=09if (largest < sizeof(struct watch_notification)) { +=09=09=09=09fprintf(stderr, "Short message header: %zu\n", largest); +=09=09=09=09return; +=09=09=09} +=09=09=09memcpy(&n, p, largest); + +=09=09=09printf("NOTIFY[%03zx]: ty=3D%06x sy=3D%02x i=3D%08x\n", +=09=09=09 p - buffer, n.n.type, n.n.subtype, n.n.info); + +=09=09=09len =3D n.n.info & WATCH_INFO_LENGTH; +=09=09=09if (len < sizeof(n.n) || len > largest) { +=09=09=09=09fprintf(stderr, "Bad message length: %zu/%zu\n", len, largest)= ; +=09=09=09=09exit(1); +=09=09=09} + +=09=09=09switch (n.n.type) { +=09=09=09case WATCH_TYPE_META: +=09=09=09=09switch (n.n.subtype) { +=09=09=09=09case WATCH_META_REMOVAL_NOTIFICATION: +=09=09=09=09=09printf("REMOVAL of watchpoint %08x\n", +=09=09=09=09=09 (n.n.info & WATCH_INFO_ID) >> +=09=09=09=09=09 WATCH_INFO_ID__SHIFT); +=09=09=09=09=09break; +=09=09=09=09default: +=09=09=09=09=09printf("other meta record\n"); +=09=09=09=09=09break; +=09=09=09=09} +=09=09=09=09break; +=09=09=09case WATCH_TYPE_KEY_NOTIFY: +=09=09=09=09saw_key_change(&n.n, len); +=09=09=09=09break; +=09=09=09default: +=09=09=09=09printf("other type\n"); +=09=09=09=09break; +=09=09=09} + +=09=09=09p +=3D len; +=09=09} +=09} +} + +static struct watch_notification_filter filter =3D { +=09.nr_filters=09=3D 1, +=09.filters =3D { +=09=09[0]=09=3D { +=09=09=09.type=09=09=09=3D WATCH_TYPE_KEY_NOTIFY, +=09=09=09.subtype_filter[0]=09=3D UINT_MAX, +=09=09}, +=09}, +}; + +int main(int argc, char **argv) +{ +=09int pipefd[2], fd; + +=09if (pipe2(pipefd, O_NOTIFICATION_PIPE) =3D=3D -1) { +=09=09perror("pipe2"); +=09=09exit(1); +=09} +=09fd =3D pipefd[0]; + +=09if (ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, BUF_SIZE) =3D=3D -1) { +=09=09perror("/dev/watch_queue(size)"); +=09=09exit(1); +=09} + +=09if (ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter) =3D=3D -1) { +=09=09perror("/dev/watch_queue(filter)"); +=09=09exit(1); +=09} + +=09if (keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fd, 0x01) =3D=3D -1) { +=09=09perror("keyctl"); +=09=09exit(1); +=09} + +=09if (keyctl_watch_key(KEY_SPEC_USER_KEYRING, fd, 0x02) =3D=3D -1) { +=09=09perror("keyctl"); +=09=09exit(1); +=09} + +=09consumer(fd); +=09exit(0); +}