1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
  23  */
  24 
  25 
  26 #ifndef _SYS_LOFI_H
  27 #define _SYS_LOFI_H
  28 
  29 #include <sys/types.h>
  30 #include <sys/time.h>
  31 #include <sys/taskq.h>
  32 #include <sys/vtoc.h>
  33 #include <sys/dkio.h>
  34 #include <sys/vnode.h>
  35 #include <sys/list.h>
  36 #include <sys/crypto/api.h>
  37 #include <sys/zone.h>
  38 
  39 #ifdef  __cplusplus
  40 extern "C" {
  41 #endif
  42 
  43 /*
  44  * /dev names:
  45  *      /dev/lofictl    - master control device
  46  *      /dev/lofi       - block devices, named by minor number
  47  *      /dev/rlofi      - character devices, named by minor number
  48  */
  49 #define LOFI_DRIVER_NAME        "lofi"
  50 #define LOFI_CTL_NODE           "ctl"
  51 #define LOFI_CTL_NAME           LOFI_DRIVER_NAME LOFI_CTL_NODE
  52 #define LOFI_BLOCK_NAME         LOFI_DRIVER_NAME
  53 #define LOFI_CHAR_NAME          "r" LOFI_DRIVER_NAME
  54 
  55 #define SEGHDR          1
  56 #define COMPRESSED      1
  57 #define UNCOMPRESSED    0
  58 #define MAXALGLEN       36
  59 
  60 /*
  61  *
  62  * Use is:
  63  *      ld = open("/dev/lofictl", O_RDWR | O_EXCL);
  64  *
  65  * lofi must be opened exclusively. Access is controlled by permissions on
  66  * the device, which is 644 by default. Write-access is required for ioctls
  67  * that change state, but only read-access is required for the ioctls that
  68  * return information. Basically, only root can add and remove files, but
  69  * non-root can look at the current lists.
  70  *
  71  * ioctl usage:
  72  *
  73  * kernel ioctls
  74  *
  75  *      strcpy(li.li_filename, "somefilename");
  76  *      ioctl(ld, LOFI_MAP_FILE, &li);
  77  *      newminor = li.li_minor;
  78  *
  79  *      strcpy(li.li_filename, "somefilename");
  80  *      ioctl(ld, LOFI_UNMAP_FILE, &li);
  81  *
  82  *      strcpy(li.li_filename, "somefilename");
  83  *      li.li_minor = minor_number;
  84  *      ioctl(ld, LOFI_MAP_FILE_MINOR, &li);
  85  *
  86  *      li.li_minor = minor_number;
  87  *      ioctl(ld, LOFI_UNMAP_FILE_MINOR, &li);
  88  *
  89  *      li.li_minor = minor_number;
  90  *      ioctl(ld, LOFI_GET_FILENAME, &li);
  91  *      filename = li.li_filename;
  92  *      encrypted = li.li_crypto_enabled;
  93  *
  94  *      strcpy(li.li_filename, "somefilename");
  95  *      ioctl(ld, LOFI_GET_MINOR, &li);
  96  *      minor = li.li_minor;
  97  *
  98  *      li.li_minor = 0;
  99  *      ioctl(ld, LOFI_GET_MAXMINOR, &li);
 100  *      maxminor = li.li_minor;
 101  *
 102  *      strcpy(li.li_filename, "somefilename");
 103  *      li.li_minor = 0;
 104  *      ioctl(ld, LOFI_CHECK_COMPRESSED, &li);
 105  *
 106  * If the 'li_force' flag is set for any of the LOFI_UNMAP_* commands, then if
 107  * the device is busy, the underlying vnode will be closed, and any subsequent
 108  * operations will fail.  It will behave as if the device had been forcibly
 109  * removed, so the DKIOCSTATE ioctl will return DKIO_DEV_GONE.  When the device
 110  * is last closed, it will be torn down.
 111  *
 112  * If the 'li_cleanup' flag is set for any of the LOFI_UNMAP_* commands, then
 113  * if the device is busy, it is marked for removal at the next time it is
 114  * no longer held open by anybody.  When the device is last closed, it will be
 115  * torn down.
 116  *
 117  * Oh, and last but not least: these ioctls are totally private and only
 118  * for use by lofiadm(1M).
 119  *
 120  */
 121 
 122 typedef enum    iv_method {
 123         IVM_NONE,       /* no iv needed, iv is null */
 124         IVM_ENC_BLKNO   /* iv is logical block no. encrypted */
 125 } iv_method_t;
 126 
 127 struct lofi_ioctl {
 128         uint32_t        li_minor;
 129         boolean_t       li_force;
 130         boolean_t       li_cleanup;
 131         char    li_filename[MAXPATHLEN];
 132 
 133         /* the following fields are required for compression support */
 134         char    li_algorithm[MAXALGLEN];
 135 
 136         /* the following fields are required for encryption support */
 137         boolean_t       li_crypto_enabled;
 138         crypto_mech_name_t      li_cipher;      /* for data */
 139         uint32_t        li_key_len;             /* for data */
 140         char            li_key[56];     /* for data: max 448-bit Blowfish key */
 141         crypto_mech_name_t      li_iv_cipher;   /* for iv derivation */
 142         uint32_t        li_iv_len;              /* for iv derivation */
 143         iv_method_t     li_iv_type;             /* for iv derivation */
 144 };
 145 
 146 #define LOFI_IOC_BASE           (('L' << 16) | ('F' << 8))
 147 
 148 #define LOFI_MAP_FILE           (LOFI_IOC_BASE | 0x01)
 149 #define LOFI_MAP_FILE_MINOR     (LOFI_IOC_BASE | 0x02)
 150 #define LOFI_UNMAP_FILE         (LOFI_IOC_BASE | 0x03)
 151 #define LOFI_UNMAP_FILE_MINOR   (LOFI_IOC_BASE | 0x04)
 152 #define LOFI_GET_FILENAME       (LOFI_IOC_BASE | 0x05)
 153 #define LOFI_GET_MINOR          (LOFI_IOC_BASE | 0x06)
 154 #define LOFI_GET_MAXMINOR       (LOFI_IOC_BASE | 0x07)
 155 #define LOFI_CHECK_COMPRESSED   (LOFI_IOC_BASE | 0x08)
 156 
 157 /*
 158  * file types that might be usable with lofi, maybe. Only regular
 159  * files are documented though.
 160  */
 161 #define S_ISLOFIABLE(mode) \
 162         (S_ISREG(mode) || S_ISBLK(mode) || S_ISCHR(mode))
 163 
 164 #if defined(_KERNEL)
 165 
 166 
 167 /*
 168  * Cache decompressed data segments for the compressed lofi images.
 169  *
 170  * To avoid that we have to decompress data of a compressed
 171  * segment multiple times when accessing parts of the segment's
 172  * data we cache the uncompressed data, using a simple linked list.
 173  */
 174 struct lofi_comp_cache {
 175         list_node_t     lc_list;                /* linked list */
 176         uchar_t         *lc_data;               /* decompressed segment data */
 177         uint64_t        lc_index;               /* segment index */
 178 };
 179 
 180 #define V_ISLOFIABLE(vtype) \
 181         ((vtype == VREG) || (vtype == VBLK) || (vtype == VCHR))
 182 
 183 /*
 184  * Pre-allocated memory buffers for the purpose of compression
 185  */
 186 struct compbuf {
 187         void            *buf;
 188         uint32_t        bufsize;
 189         int             inuse;
 190 };
 191 
 192 /*
 193  * Need exactly 6 bytes to identify encrypted lofi image
 194  */
 195 extern const char lofi_crypto_magic[6];
 196 #define LOFI_CRYPTO_MAGIC       { 'C', 'F', 'L', 'O', 'F', 'I' }
 197 #define LOFI_CRYPTO_VERSION     ((uint16_t)0)
 198 #define LOFI_CRYPTO_DATA_SECTOR ((uint32_t)16)          /* for version 0 */
 199 
 200 /*
 201  * Crypto metadata for encrypted lofi images
 202  * The fields here only satisfy initial implementation requirements.
 203  */
 204 struct crypto_meta {
 205         char            magic[6];               /* LOFI_CRYPTO_MAGIC */
 206         uint16_t        version;                /* version of encrypted lofi */
 207         char            reserved1[96];          /* future use */
 208         uint32_t        data_sector;            /* start of data area */
 209         char            pad[404];               /* end on DEV_BSIZE bdry */
 210         /* second header block is not defined at this time */
 211 };
 212 
 213 struct lofi_state {
 214         vnode_t         *ls_vp;         /* open real vnode */
 215         vnode_t         *ls_stacked_vp; /* open vnode */
 216         kmutex_t        ls_vp_lock;     /* protects ls_vp */
 217         kcondvar_t      ls_vp_cv;       /* signal changes to ls_vp */
 218         uint32_t        ls_vp_iocount;  /* # pending I/O requests */
 219         boolean_t       ls_vp_closereq; /* force close requested */
 220         u_offset_t      ls_vp_size;
 221         uint32_t        ls_blk_open;
 222         uint32_t        ls_chr_open;
 223         uint32_t        ls_lyr_open_count;
 224         int             ls_openflag;
 225         boolean_t       ls_cleanup;     /* cleanup on close */
 226         taskq_t         *ls_taskq;
 227         kstat_t         *ls_kstat;
 228         kmutex_t        ls_kstat_lock;
 229         struct dk_geom  ls_dkg;
 230         struct vtoc     ls_vtoc;
 231         struct dk_cinfo ls_ci;
 232         zone_ref_t      ls_zone;
 233         list_node_t     ls_list;        /* all lofis */
 234         dev_t           ls_dev;         /* this node's dev_t */
 235 
 236         /* the following fields are required for compression support */
 237         int             ls_comp_algorithm_index; /* idx into compress_table */
 238         char            ls_comp_algorithm[MAXALGLEN];
 239         uint32_t        ls_uncomp_seg_sz; /* sz of uncompressed segment */
 240         uint32_t        ls_comp_index_sz; /* number of index entries */
 241         uint32_t        ls_comp_seg_shift; /* exponent for byte shift */
 242         uint32_t        ls_uncomp_last_seg_sz; /* sz of last uncomp segment */
 243         uint64_t        ls_comp_offbase; /* offset of actual compressed data */
 244         uint64_t        *ls_comp_seg_index; /* array of index entries */
 245         caddr_t         ls_comp_index_data; /* index pages loaded from file */
 246         uint32_t        ls_comp_index_data_sz;
 247         u_offset_t      ls_vp_comp_size; /* actual compressed file size */
 248 
 249         /* pre-allocated list of buffers for compressed segment data */
 250         kmutex_t        ls_comp_bufs_lock;
 251         struct compbuf  *ls_comp_bufs;
 252 
 253         /* lock and anchor for compressed segment caching */
 254         kmutex_t        ls_comp_cache_lock;     /* protects ls_comp_cache */
 255         list_t          ls_comp_cache;          /* cached decompressed segs */
 256         uint32_t        ls_comp_cache_count;
 257 
 258         /* the following fields are required for encryption support */
 259         boolean_t               ls_crypto_enabled;
 260         u_offset_t              ls_crypto_offset;       /* crypto meta size */
 261         struct crypto_meta      ls_crypto;
 262         crypto_mechanism_t      ls_mech;        /* for data encr/decr */
 263         crypto_key_t            ls_key;         /* for data encr/decr */
 264         crypto_mechanism_t      ls_iv_mech;     /* for iv derivation */
 265         size_t                  ls_iv_len;      /* for iv derivation */
 266         iv_method_t             ls_iv_type;     /* for iv derivation */
 267         kmutex_t                ls_crypto_lock;
 268         crypto_ctx_template_t   ls_ctx_tmpl;
 269 
 270 };
 271 
 272 #endif  /* _KERNEL */
 273 
 274 /*
 275  * Common signature for all lofi compress functions
 276  */
 277 typedef int lofi_compress_func_t(void *src, size_t srclen, void *dst,
 278         size_t *destlen, int level);
 279 
 280 /*
 281  * Information about each compression function
 282  */
 283 typedef struct lofi_compress_info {
 284         lofi_compress_func_t    *l_decompress;
 285         lofi_compress_func_t    *l_compress;
 286         int                     l_level;
 287         char                    *l_name;        /* algorithm name */
 288 } lofi_compress_info_t;
 289 
 290 enum lofi_compress {
 291         LOFI_COMPRESS_GZIP = 0,
 292         LOFI_COMPRESS_GZIP_6 = 1,
 293         LOFI_COMPRESS_GZIP_9 = 2,
 294         LOFI_COMPRESS_LZMA = 3,
 295         LOFI_COMPRESS_FUNCTIONS
 296 };
 297 
 298 #ifdef  __cplusplus
 299 }
 300 #endif
 301 
 302 #endif  /* _SYS_LOFI_H */