diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/Makefile | 3 | ||||
| -rw-r--r-- | block/bsg.c | 38 | ||||
| -rw-r--r-- | block/cmd-filter.c | 325 | ||||
| -rw-r--r-- | block/genhd.c | 2 | ||||
| -rw-r--r-- | block/scsi_ioctl.c | 121 |
5 files changed, 361 insertions, 128 deletions
diff --git a/block/Makefile b/block/Makefile index 045f7b6..208000b 100644 --- a/block/Makefile +++ b/block/Makefile @@ -4,7 +4,8 @@ obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \ blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \ - blk-exec.o blk-merge.o ioctl.o genhd.o scsi_ioctl.o + blk-exec.o blk-merge.o ioctl.o genhd.o scsi_ioctl.o \ + cmd-filter.o obj-$(CONFIG_BLK_DEV_BSG) += bsg.o obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o diff --git a/block/bsg.c b/block/bsg.c index f0b7cd3..439940c 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -44,11 +44,12 @@ struct bsg_device { char name[BUS_ID_SIZE]; int max_queue; unsigned long flags; + struct blk_scsi_cmd_filter *cmd_filter; + mode_t *f_mode; }; enum { BSG_F_BLOCK = 1, - BSG_F_WRITE_PERM = 2, }; #define BSG_DEFAULT_CMDS 64 @@ -172,7 +173,7 @@ unlock: } static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq, - struct sg_io_v4 *hdr, int has_write_perm) + struct sg_io_v4 *hdr, struct bsg_device *bd) { if (hdr->request_len > BLK_MAX_CDB) { rq->cmd = kzalloc(hdr->request_len, GFP_KERNEL); @@ -185,7 +186,8 @@ static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq, return -EFAULT; if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) { - if (blk_verify_command(rq->cmd, has_write_perm)) + if (blk_cmd_filter_verify_command(bd->cmd_filter, rq->cmd, + bd->f_mode)) return -EPERM; } else if (!capable(CAP_SYS_RAWIO)) return -EPERM; @@ -263,8 +265,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) rq = blk_get_request(q, rw, GFP_KERNEL); if (!rq) return ERR_PTR(-ENOMEM); - ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM, - &bd->flags)); + ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd); if (ret) goto out; @@ -566,12 +567,23 @@ static inline void bsg_set_block(struct bsg_device *bd, struct file *file) set_bit(BSG_F_BLOCK, &bd->flags); } -static inline void bsg_set_write_perm(struct bsg_device *bd, struct file *file) +static void bsg_set_cmd_filter(struct bsg_device *bd, + struct file *file) { - if (file->f_mode & FMODE_WRITE) - set_bit(BSG_F_WRITE_PERM, &bd->flags); - else - clear_bit(BSG_F_WRITE_PERM, &bd->flags); + struct inode *inode; + struct gendisk *disk; + + if (!file) + return; + + inode = file->f_dentry->d_inode; + if (!inode) + return; + + disk = inode->i_bdev->bd_disk; + + bd->cmd_filter = &disk->cmd_filter; + bd->f_mode = &file->f_mode; } /* @@ -595,6 +607,8 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) dprintk("%s: read %Zd bytes\n", bd->name, count); bsg_set_block(bd, file); + bsg_set_cmd_filter(bd, file); + bytes_read = 0; ret = __bsg_read(buf, count, bd, NULL, &bytes_read); *ppos = bytes_read; @@ -668,7 +682,7 @@ bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) dprintk("%s: write %Zd bytes\n", bd->name, count); bsg_set_block(bd, file); - bsg_set_write_perm(bd, file); + bsg_set_cmd_filter(bd, file); bytes_written = 0; ret = __bsg_write(bd, buf, count, &bytes_written); @@ -771,7 +785,9 @@ static struct bsg_device *bsg_add_device(struct inode *inode, } bd->queue = rq; + bsg_set_block(bd, file); + bsg_set_cmd_filter(bd, file); atomic_set(&bd->ref_count, 1); mutex_lock(&bsg_mutex); diff --git a/block/cmd-filter.c b/block/cmd-filter.c new file mode 100644 index 0000000..35e327c --- /dev/null +++ b/block/cmd-filter.c @@ -0,0 +1,325 @@ +/* + * Copyright 2004 Peter M. Jones <pjones@redhat.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public Licens + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- + * + */ + +#include <linux/list.h> +#include <linux/genhd.h> +#include <linux/spinlock.h> +#include <linux/parser.h> +#include <linux/capability.h> +#include <linux/bitops.h> + +#include <scsi/scsi.h> +#include <linux/cdrom.h> + +int blk_cmd_filter_verify_command(struct blk_scsi_cmd_filter *filter, + unsigned char *cmd, mode_t *f_mode) +{ + /* root can do any command. */ + if (capable(CAP_SYS_RAWIO)) + return 0; + + /* if there's no filter set, assume we're filtering everything out */ + if (!filter) + return -EPERM; + + /* Anybody who can open the device can do a read-safe command */ + if (test_bit(cmd[0], filter->read_ok)) + return 0; + + /* Write-safe commands require a writable open */ + if (test_bit(cmd[0], filter->write_ok) && (*f_mode & FMODE_WRITE)) + return 0; + + return -EPERM; +} +EXPORT_SYMBOL(blk_cmd_filter_verify_command); + +int blk_verify_command(struct file *file, unsigned char *cmd) +{ + struct gendisk *disk; + struct inode *inode; + + if (!file) + return -EINVAL; + + inode = file->f_dentry->d_inode; + if (!inode) + return -EINVAL; + + disk = inode->i_bdev->bd_disk; + + return blk_cmd_filter_verify_command(&disk->cmd_filter, + cmd, &file->f_mode); +} +EXPORT_SYMBOL(blk_verify_command); + +/* and now, the sysfs stuff */ +static ssize_t rcf_cmds_show(struct blk_scsi_cmd_filter *filter, char *page, + int rw) +{ + char *npage = page; + unsigned long *okbits; + int i; + + if (rw == READ) + okbits = filter->read_ok; + else + okbits = filter->write_ok; + + for (i = 0; i < BLK_SCSI_MAX_CMDS; i++) { + if (test_bit(i, okbits)) { + sprintf(npage, "%02x", i); + npage += 2; + if (i < BLK_SCSI_MAX_CMDS - 1) + sprintf(npage++, " "); + } + } + + if (npage != page) + npage += sprintf(npage, "\n"); + + return npage - page; +} + +static ssize_t rcf_readcmds_show(struct blk_scsi_cmd_filter *filter, char *page) +{ + return rcf_cmds_show(filter, page, READ); +} + +static ssize_t rcf_writecmds_show(struct blk_scsi_cmd_filter *filter, + char *page) +{ + return rcf_cmds_show(filter, page, WRITE); +} + +static ssize_t rcf_cmds_store(struct blk_scsi_cmd_filter *filter, + const char *page, size_t count, int rw) +{ + ssize_t ret = 0; + unsigned long okbits[BLK_SCSI_CMD_PER_LONG], *target_okbits; + int cmd, status, len; + substring_t ss; + + memset(&okbits, 0, sizeof(okbits)); + + for (len = strlen(page); len > 0; len -= 3) { + if (len < 2) + break; + ss.from = (char *) page + ret; + ss.to = (char *) page + ret + 2; + ret += 3; + status = match_hex(&ss, &cmd); + /* either of these cases means invalid input, so do nothing. */ + if (status || cmd >= BLK_SCSI_MAX_CMDS) + return -EINVAL; + + __set_bit(cmd, okbits); + } + + if (rw == READ) + target_okbits = filter->read_ok; + else + target_okbits = filter->write_ok; + + memmove(target_okbits, okbits, sizeof(okbits)); + return count; +} + +static ssize_t rcf_readcmds_store(struct blk_scsi_cmd_filter *filter, + const char *page, size_t count) +{ + return rcf_cmds_store(filter, page, count, READ); +} + +static ssize_t rcf_writecmds_store(struct blk_scsi_cmd_filter *filter, + const char *page, size_t count) +{ + return rcf_cmds_store(filter, page, count, WRITE); +} + +struct rcf_sysfs_entry { + struct attribute attr; + ssize_t (*show)(struct blk_scsi_cmd_filter *, char *); + ssize_t (*store)(struct blk_scsi_cmd_filter *, const char *, size_t); +}; + +static struct rcf_sysfs_entry rcf_readcmds_entry = { + .attr = { .name = "read_table", .mode = S_IRUGO | S_IWUSR }, + .show = rcf_readcmds_show, + .store = rcf_readcmds_store, +}; + +static struct rcf_sysfs_entry rcf_writecmds_entry = { + .attr = {.name = "write_table", .mode = S_IRUGO | S_IWUSR }, + .show = rcf_writecmds_show, + .store = rcf_writecmds_store, +}; + +static struct attribute *default_attrs[] = { + &rcf_readcmds_entry.attr, + &rcf_writecmds_entry.attr, + NULL, +}; + +#define to_rcf(atr) container_of((atr), struct rcf_sysfs_entry, attr) + +static ssize_t +rcf_attr_show(struct kobject *kobj, struct attribute *attr, char *page) +{ + struct rcf_sysfs_entry *entry = to_rcf(attr); + struct blk_scsi_cmd_filter *filter; + + filter = container_of(kobj, struct blk_scsi_cmd_filter, kobj); + if (entry->show) + return entry->show(filter, page); + + return 0; +} + +static ssize_t +rcf_attr_store(struct kobject *kobj, struct attribute *attr, + const char *page, size_t length) +{ + struct rcf_sysfs_entry *entry = to_rcf(attr); + struct blk_scsi_cmd_filter *filter; + + if (!capable(CAP_SYS_RAWIO)) + return -EPERM; + + if (!entry->store) + return -EINVAL; + + filter = container_of(kobj, struct blk_scsi_cmd_filter, kobj); + return entry->store(filter, page, length); +} + +static struct sysfs_ops rcf_sysfs_ops = { + .show = rcf_attr_show, + .store = rcf_attr_store, +}; + +static struct kobj_type rcf_ktype = { + .sysfs_ops = &rcf_sysfs_ops, + .default_attrs = default_attrs, +}; + +static void rcf_set_defaults(struct blk_scsi_cmd_filter *filter) +{ + /* Basic read-only commands */ + __set_bit(TEST_UNIT_READY, filter->read_ok); + __set_bit(REQUEST_SENSE, filter->read_ok); + __set_bit(READ_6, filter->read_ok); + __set_bit(READ_10, filter->read_ok); + __set_bit(READ_12, filter->read_ok); + __set_bit(READ_16, filter->read_ok); + __set_bit(READ_BUFFER, filter->read_ok); + __set_bit(READ_DEFECT_DATA, filter->read_ok); + __set_bit(READ_LONG, filter->read_ok); + __set_bit(INQUIRY, filter->read_ok); + __set_bit(MODE_SENSE, filter->read_ok); + __set_bit(MODE_SENSE_10, filter->read_ok); + __set_bit(LOG_SENSE, filter->read_ok); + __set_bit(START_STOP, filter->read_ok); + __set_bit(GPCMD_VERIFY_10, filter->read_ok); + __set_bit(VERIFY_16, filter->read_ok); + __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok); + + /* Audio CD commands */ + __set_bit(GPCMD_PLAY_CD, filter->read_ok); + __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok); + __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok); + __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok); + __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok); + + /* CD/DVD data reading */ + __set_bit(GPCMD_READ_CD, filter->read_ok); + __set_bit(GPCMD_READ_CD_MSF, filter->read_ok); + __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok); + __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok); + __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok); + __set_bit(GPCMD_READ_HEADER, filter->read_ok); + __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok); + __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok); + __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok); + __set_bit(GPCMD_REPORT_KEY, filter->read_ok); + __set_bit(GPCMD_SCAN, filter->read_ok); + __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok); + __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok); + __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok); + __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok); + __set_bit(GPCMD_SEEK, filter->read_ok); + __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok); + + /* Basic writing commands */ + __set_bit(WRITE_6, filter->write_ok); + __set_bit(WRITE_10, filter->write_ok); + __set_bit(WRITE_VERIFY, filter->write_ok); + __set_bit(WRITE_12, filter->write_ok); + __set_bit(WRITE_VERIFY_12, filter->write_ok); + __set_bit(WRITE_16, filter->write_ok); + __set_bit(WRITE_LONG, filter->write_ok); + __set_bit(WRITE_LONG_2, filter->write_ok); + __set_bit(ERASE, filter->write_ok); + __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok); + __set_bit(MODE_SELECT, filter->write_ok); + __set_bit(LOG_SELECT, filter->write_ok); + __set_bit(GPCMD_BLANK, filter->write_ok); + __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok); + __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok); + __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok); + __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok); + __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok); + __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok); + __set_bit(GPCMD_SEND_EVENT, filter->write_ok); + __set_bit(GPCMD_SEND_KEY, filter->write_ok); + __set_bit(GPCMD_SEND_OPC, filter->write_ok); + __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok); + __set_bit(GPCMD_SET_SPEED, filter->write_ok); + __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok); + __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok); + __set_bit(GPCMD_SET_STREAMING, filter->write_ok); +} + +int blk_register_filter(struct gendisk *disk) +{ + int ret; + struct blk_scsi_cmd_filter *filter = &disk->cmd_filter; + struct kobject *parent = kobject_get(disk->holder_dir->parent); + + if (!parent) + return -ENODEV; + + ret = kobject_init_and_add(&filter->kobj, &rcf_ktype, parent, + "%s", "cmd_filter"); + + if (ret < 0) + return ret; + + rcf_set_defaults(filter); + return 0; +} + +void blk_unregister_filter(struct gendisk *disk) +{ + struct blk_scsi_cmd_filter *filter = &disk->cmd_filter; + + kobject_put(&filter->kobj); + kobject_put(disk->holder_dir->parent); +} + diff --git a/block/genhd.c b/block/genhd.c index 43e468e..9074f38 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -189,6 +189,7 @@ void add_disk(struct gendisk *disk) disk->minors, NULL, exact_match, exact_lock, disk); register_disk(disk); blk_register_queue(disk); + blk_register_filter(disk); bdi = &disk->queue->backing_dev_info; bdi_register_dev(bdi, MKDEV(disk->major, disk->first_minor)); @@ -200,6 +201,7 @@ EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ void unlink_gendisk(struct gendisk *disk) { + blk_unregister_filter(disk); sysfs_remove_link(&disk->dev.kobj, "bdi"); bdi_unregister(&disk->queue->backing_dev_info); blk_unregister_queue(disk); diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index 78199c0..c5b9bcf 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -105,120 +105,12 @@ static int sg_emulated_host(struct request_queue *q, int __user *p) return put_user(1, p); } -#define CMD_READ_SAFE 0x01 -#define CMD_WRITE_SAFE 0x02 -#define CMD_WARNED 0x04 -#define safe_for_read(cmd) [cmd] = CMD_READ_SAFE -#define safe_for_write(cmd) [cmd] = CMD_WRITE_SAFE - -int blk_verify_command(unsigned char *cmd, int has_write_perm) -{ - static unsigned char cmd_type[256] = { - - /* Basic read-only commands */ - safe_for_read(TEST_UNIT_READY), - safe_for_read(REQUEST_SENSE), - safe_for_read(READ_6), - safe_for_read(READ_10), - safe_for_read(READ_12), - safe_for_read(READ_16), - safe_for_read(READ_BUFFER), - safe_for_read(READ_DEFECT_DATA), - safe_for_read(READ_LONG), - safe_for_read(INQUIRY), - safe_for_read(MODE_SENSE), - safe_for_read(MODE_SENSE_10), - safe_for_read(LOG_SENSE), - safe_for_read(START_STOP), - safe_for_read(GPCMD_VERIFY_10), - safe_for_read(VERIFY_16), - - /* Audio CD commands */ - safe_for_read(GPCMD_PLAY_CD), - safe_for_read(GPCMD_PLAY_AUDIO_10), - safe_for_read(GPCMD_PLAY_AUDIO_MSF), - safe_for_read(GPCMD_PLAY_AUDIO_TI), - safe_for_read(GPCMD_PAUSE_RESUME), - - /* CD/DVD data reading */ - safe_for_read(GPCMD_READ_BUFFER_CAPACITY), - safe_for_read(GPCMD_READ_CD), - safe_for_read(GPCMD_READ_CD_MSF), - safe_for_read(GPCMD_READ_DISC_INFO), - safe_for_read(GPCMD_READ_CDVD_CAPACITY), - safe_for_read(GPCMD_READ_DVD_STRUCTURE), - safe_for_read(GPCMD_READ_HEADER), - safe_for_read(GPCMD_READ_TRACK_RZONE_INFO), - safe_for_read(GPCMD_READ_SUBCHANNEL), - safe_for_read(GPCMD_READ_TOC_PMA_ATIP), - safe_for_read(GPCMD_REPORT_KEY), - safe_for_read(GPCMD_SCAN), - safe_for_read(GPCMD_GET_CONFIGURATION), - safe_for_read(GPCMD_READ_FORMAT_CAPACITIES), - safe_for_read(GPCMD_GET_EVENT_STATUS_NOTIFICATION), - safe_for_read(GPCMD_GET_PERFORMANCE), - safe_for_read(GPCMD_SEEK), - safe_for_read(GPCMD_STOP_PLAY_SCAN), - - /* Basic writing commands */ - safe_for_write(WRITE_6), - safe_for_write(WRITE_10), - safe_for_write(WRITE_VERIFY), - safe_for_write(WRITE_12), - safe_for_write(WRITE_VERIFY_12), - safe_for_write(WRITE_16), - safe_for_write(WRITE_LONG), - safe_for_write(WRITE_LONG_2), - safe_for_write(ERASE), - safe_for_write(GPCMD_MODE_SELECT_10), - safe_for_write(MODE_SELECT), - safe_for_write(LOG_SELECT), - safe_for_write(GPCMD_BLANK), - safe_for_write(GPCMD_CLOSE_TRACK), - safe_for_write(GPCMD_FLUSH_CACHE), - safe_for_write(GPCMD_FORMAT_UNIT), - safe_for_write(GPCMD_REPAIR_RZONE_TRACK), - safe_for_write(GPCMD_RESERVE_RZONE_TRACK), - safe_for_write(GPCMD_SEND_DVD_STRUCTURE), - safe_for_write(GPCMD_SEND_EVENT), - safe_for_write(GPCMD_SEND_KEY), - safe_for_write(GPCMD_SEND_OPC), - safe_for_write(GPCMD_SEND_CUE_SHEET), - safe_for_write(GPCMD_SET_SPEED), - safe_for_write(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL), - safe_for_write(GPCMD_LOAD_UNLOAD), - safe_for_write(GPCMD_SET_STREAMING), - }; - unsigned char type = cmd_type[cmd[0]]; - - /* Anybody who can open the device can do a read-safe command */ - if (type & CMD_READ_SAFE) - return 0; - - /* Write-safe commands just require a writable open.. */ - if ((type & CMD_WRITE_SAFE) && has_write_perm) - return 0; - - /* And root can do any command.. */ - if (capable(CAP_SYS_RAWIO)) - return 0; - - if (!type) { - cmd_type[cmd[0]] = CMD_WARNED; - printk(KERN_WARNING "scsi: unknown opcode 0x%02x\n", cmd[0]); - } - - /* Otherwise fail it with an "Operation not permitted" */ - return -EPERM; -} -EXPORT_SYMBOL_GPL(blk_verify_command); - static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq, - struct sg_io_hdr *hdr, int has_write_perm) + struct sg_io_hdr *hdr, struct file *file) { if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len)) return -EFAULT; - if (blk_verify_command(rq->cmd, has_write_perm)) + if (blk_verify_command(file, rq->cmd)) return -EPERM; /* @@ -287,7 +179,7 @@ static int sg_io(struct file *file, struct request_queue *q, struct gendisk *bd_disk, struct sg_io_hdr *hdr) { unsigned long start_time; - int writing = 0, ret = 0, has_write_perm = 0; + int writing = 0, ret = 0; struct request *rq; char sense[SCSI_SENSE_BUFFERSIZE]; struct bio *bio; @@ -316,10 +208,7 @@ static int sg_io(struct file *file, struct request_queue *q, if (!rq) return -ENOMEM; - if (file) - has_write_perm = file->f_mode & FMODE_WRITE; - - if (blk_fill_sghdr_rq(q, rq, hdr, has_write_perm)) { + if (blk_fill_sghdr_rq(q, rq, hdr, file)) { blk_put_request(rq); return -EFAULT; } @@ -451,7 +340,7 @@ int sg_scsi_ioctl(struct file *file, struct request_queue *q, if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len)) goto error; - err = blk_verify_command(rq->cmd, file->f_mode & FMODE_WRITE); + err = blk_verify_command(file, rq->cmd); if (err) goto error; |