diff options
Diffstat (limited to 'libblkid/src/superblocks/iso9660.c')
| -rw-r--r-- | libblkid/src/superblocks/iso9660.c | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/libblkid/src/superblocks/iso9660.c b/libblkid/src/superblocks/iso9660.c new file mode 100644 index 0000000..289a325 --- /dev/null +++ b/libblkid/src/superblocks/iso9660.c @@ -0,0 +1,336 @@ +/* + * Copyright (C) 1999 by Andries Brouwer + * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o + * Copyright (C) 2001 by Andreas Dilger + * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> + * Copyright (C) 2008 Karel Zak <kzak@redhat.com> + * + * Inspired also by libvolume_id by + * Kay Sievers <kay.sievers@vrfy.org> + * + * This file may be redistributed under the terms of the + * GNU Lesser General Public License. + */ +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <stdint.h> +#include <ctype.h> + +#include "superblocks.h" +#include "cctype.h" + +struct iso9660_date { + unsigned char year[4]; + unsigned char month[2]; + unsigned char day[2]; + unsigned char hour[2]; + unsigned char minute[2]; + unsigned char second[2]; + unsigned char hundredth[2]; + unsigned char offset; +} __attribute__ ((packed)); + +/* PVD - Primary volume descriptor */ +struct iso_volume_descriptor { + unsigned char vd_type; + unsigned char vd_id[5]; + unsigned char vd_version; + unsigned char flags; + unsigned char system_id[32]; + unsigned char volume_id[32]; + unsigned char unused[8]; + unsigned char space_size[8]; + unsigned char escape_sequences[8]; + unsigned char unused2[94]; + unsigned char volume_set_id[128]; + unsigned char publisher_id[128]; + unsigned char data_preparer_id[128]; + unsigned char application_id[128]; + unsigned char unused3[111]; + struct iso9660_date created; + struct iso9660_date modified; +} __attribute__((packed)); + +/* Boot Record */ +struct boot_record { + unsigned char vd_type; + unsigned char vd_id[5]; + unsigned char vd_version; + unsigned char boot_system_id[32]; + unsigned char boot_id[32]; + unsigned char unused[1]; +} __attribute__((packed)); + +#define ISO_SUPERBLOCK_OFFSET 0x8000 +#define ISO_SECTOR_SIZE 0x800 +#define ISO_VD_BOOT_RECORD 0x0 +#define ISO_VD_PRIMARY 0x1 +#define ISO_VD_SUPPLEMENTARY 0x2 +#define ISO_VD_END 0xff +#define ISO_VD_MAX 16 + +struct high_sierra_volume_descriptor { + unsigned char foo[8]; + unsigned char type; + unsigned char id[5]; + unsigned char version; + unsigned char unused1; + unsigned char system_id[32]; + unsigned char volume_id[32]; +} __attribute__((packed)); + +/* old High Sierra format */ +static int probe_iso9660_hsfs(blkid_probe pr, const struct blkid_idmag *mag) +{ + struct high_sierra_volume_descriptor *iso; + + iso = blkid_probe_get_sb(pr, mag, struct high_sierra_volume_descriptor); + if (!iso) + return errno ? -errno : 1; + + blkid_probe_set_block_size(pr, ISO_SECTOR_SIZE); + blkid_probe_set_version(pr, "High Sierra"); + blkid_probe_set_label(pr, iso->volume_id, sizeof(iso->volume_id)); + return 0; +} + +static int probe_iso9660_set_uuid (blkid_probe pr, const struct iso9660_date *date) +{ + unsigned char buffer[16]; + unsigned int i, zeros = 0; + + buffer[0] = date->year[0]; + buffer[1] = date->year[1]; + buffer[2] = date->year[2]; + buffer[3] = date->year[3]; + buffer[4] = date->month[0]; + buffer[5] = date->month[1]; + buffer[6] = date->day[0]; + buffer[7] = date->day[1]; + buffer[8] = date->hour[0]; + buffer[9] = date->hour[1]; + buffer[10] = date->minute[0]; + buffer[11] = date->minute[1]; + buffer[12] = date->second[0]; + buffer[13] = date->second[1]; + buffer[14] = date->hundredth[0]; + buffer[15] = date->hundredth[1]; + + /* count the number of zeros ('0') in the date buffer */ + for (i = 0, zeros = 0; i < sizeof(buffer); i++) + if (buffer[i] == '0') + zeros++; + + /* due to the iso9660 standard if all date fields are '0' and offset is 0, the date is unset */ + if (zeros == sizeof(buffer) && date->offset == 0) + return 0; + + /* generate an UUID using this date and return success */ + blkid_probe_sprintf_uuid (pr, buffer, sizeof(buffer), + "%c%c%c%c-%c%c-%c%c-%c%c-%c%c-%c%c-%c%c", + buffer[0], buffer[1], buffer[2], buffer[3], + buffer[4], buffer[5], + buffer[6], buffer[7], + buffer[8], buffer[9], + buffer[10], buffer[11], + buffer[12], buffer[13], + buffer[14], buffer[15]); + + return 1; +} + +static int is_str_empty(const unsigned char *str, size_t len) +{ + size_t i; + + if (!str || !*str) + return 1; + + for (i = 0; i < len; i++) + if (!isspace(str[i])) + return 0; + return 1; +} + +static int is_utf16be_str_empty(unsigned char *utf16, size_t len) +{ + size_t i; + + for (i = 0; i < len; i += 2) { + if (utf16[i] != 0x0 || !isspace(utf16[i + 1])) + return 0; + } + return 1; +} + +/* if @utf16 is prefix of @ascii (ignoring non-representable characters and upper-case conversion) + * then reconstruct prefix from @utf16 and @ascii, append suffix from @ascii, fill it into @out + * and returns length of bytes written into @out; otherwise returns zero */ +static size_t merge_utf16be_ascii(unsigned char *out, const unsigned char *utf16, const unsigned char *ascii, size_t len) +{ + size_t o, a, u; + + for (o = 0, a = 0, u = 0; u + 1 < len && a < len; o += 2, a++, u += 2) { + /* Surrogate pair with code point above U+FFFF */ + if (utf16[u] >= 0xD8 && utf16[u] <= 0xDB && u + 3 < len && + utf16[u + 2] >= 0xDC && utf16[u + 2] <= 0xDF) { + out[o++] = utf16[u++]; + out[o++] = utf16[u++]; + } + /* Value '_' is replacement for non-representable character */ + if (ascii[a] == '_') { + out[o] = utf16[u]; + out[o + 1] = utf16[u + 1]; + } else if (utf16[u] == 0x00 && utf16[u + 1] == '_') { + out[o] = 0x00; + out[o + 1] = ascii[a]; + } else if (utf16[u] == 0x00 && c_toupper(ascii[a]) == c_toupper(utf16[u + 1])) { + out[o] = 0x00; + out[o + 1] = c_isupper(ascii[a]) ? utf16[u + 1] : ascii[a]; + } else { + return 0; + } + } + + for (; a < len; o += 2, a++) { + out[o] = 0x00; + out[o + 1] = ascii[a]; + } + + return o; +} + +/* iso9660 [+ Microsoft Joliet Extension] */ +static int probe_iso9660(blkid_probe pr, const struct blkid_idmag *mag) +{ + struct boot_record *boot = NULL; + struct iso_volume_descriptor *pvd = NULL; + struct iso_volume_descriptor *joliet = NULL; + unsigned char buf[256]; + size_t len; + int is_unicode_empty; + int is_ascii_empty; + int i; + uint64_t off; + + if (blkid_probe_get_hint(pr, mag->hoff, &off) < 0) + off = 0; + + if (off % ISO_SECTOR_SIZE) + return 1; + + if (strcmp(mag->magic, "CDROM") == 0) + return probe_iso9660_hsfs(pr, mag); + + for (i = 0, off += ISO_SUPERBLOCK_OFFSET; i < ISO_VD_MAX && (!boot || !pvd || !joliet); i++, off += ISO_SECTOR_SIZE) { + unsigned char *desc = + blkid_probe_get_buffer(pr, + off, + max(sizeof(struct boot_record), + sizeof(struct iso_volume_descriptor))); + + if (desc == NULL || desc[0] == ISO_VD_END) + break; + else if (!boot && desc[0] == ISO_VD_BOOT_RECORD) + boot = (struct boot_record *)desc; + else if (!pvd && desc[0] == ISO_VD_PRIMARY) + pvd = (struct iso_volume_descriptor *)desc; + else if (!joliet && desc[0] == ISO_VD_SUPPLEMENTARY) { + joliet = (struct iso_volume_descriptor *)desc; + if (memcmp(joliet->escape_sequences, "%/@", 3) != 0 && + memcmp(joliet->escape_sequences, "%/C", 3) != 0 && + memcmp(joliet->escape_sequences, "%/E", 3) != 0) + joliet = NULL; + } + } + + if (!pvd) + return errno ? -errno : 1; + + blkid_probe_set_block_size(pr, ISO_SECTOR_SIZE); + + if (joliet && (len = merge_utf16be_ascii(buf, joliet->system_id, pvd->system_id, sizeof(pvd->system_id))) != 0) + blkid_probe_set_utf8_id_label(pr, "SYSTEM_ID", buf, len, UL_ENCODE_UTF16BE); + else if (joliet) + blkid_probe_set_utf8_id_label(pr, "SYSTEM_ID", joliet->system_id, sizeof(joliet->system_id), UL_ENCODE_UTF16BE); + else + blkid_probe_set_id_label(pr, "SYSTEM_ID", pvd->system_id, sizeof(pvd->system_id)); + + if (joliet && (len = merge_utf16be_ascii(buf, joliet->volume_set_id, pvd->volume_set_id, sizeof(pvd->volume_set_id))) != 0) + blkid_probe_set_utf8_id_label(pr, "VOLUME_SET_ID", buf, len, UL_ENCODE_UTF16BE); + else if (joliet) + blkid_probe_set_utf8_id_label(pr, "VOLUME_SET_ID", joliet->volume_set_id, sizeof(joliet->volume_set_id), UL_ENCODE_UTF16BE); + else + blkid_probe_set_id_label(pr, "VOLUME_SET_ID", pvd->volume_set_id, sizeof(pvd->volume_set_id)); + + is_ascii_empty = (is_str_empty(pvd->publisher_id, sizeof(pvd->publisher_id)) || pvd->publisher_id[0] == '_'); + is_unicode_empty = (!joliet || is_utf16be_str_empty(joliet->publisher_id, sizeof(joliet->publisher_id)) || (joliet->publisher_id[0] == 0x00 && joliet->publisher_id[1] == '_')); + if (!is_unicode_empty && !is_ascii_empty && (len = merge_utf16be_ascii(buf, joliet->publisher_id, pvd->publisher_id, sizeof(pvd->publisher_id))) != 0) + blkid_probe_set_utf8_id_label(pr, "PUBLISHER_ID", buf, len, UL_ENCODE_UTF16BE); + else if (!is_unicode_empty) + blkid_probe_set_utf8_id_label(pr, "PUBLISHER_ID", joliet->publisher_id, sizeof(joliet->publisher_id), UL_ENCODE_UTF16BE); + else if (!is_ascii_empty) + blkid_probe_set_id_label(pr, "PUBLISHER_ID", pvd->publisher_id, sizeof(pvd->publisher_id)); + + is_ascii_empty = (is_str_empty(pvd->data_preparer_id, sizeof(pvd->data_preparer_id)) || pvd->data_preparer_id[0] == '_'); + is_unicode_empty = (!joliet || is_utf16be_str_empty(joliet->data_preparer_id, sizeof(joliet->data_preparer_id)) || (joliet->data_preparer_id[0] == 0x00 && joliet->data_preparer_id[1] == '_')); + if (!is_unicode_empty && !is_ascii_empty && (len = merge_utf16be_ascii(buf, joliet->data_preparer_id, pvd->data_preparer_id, sizeof(pvd->data_preparer_id))) != 0) + blkid_probe_set_utf8_id_label(pr, "DATA_PREPARER_ID", buf, len, UL_ENCODE_UTF16BE); + else if (!is_unicode_empty) + blkid_probe_set_utf8_id_label(pr, "DATA_PREPARER_ID", joliet->data_preparer_id, sizeof(joliet->data_preparer_id), UL_ENCODE_UTF16BE); + else if (!is_ascii_empty) + blkid_probe_set_id_label(pr, "DATA_PREPARER_ID", pvd->data_preparer_id, sizeof(pvd->data_preparer_id)); + + is_ascii_empty = (is_str_empty(pvd->application_id, sizeof(pvd->application_id)) || pvd->application_id[0] == '_'); + is_unicode_empty = (!joliet || is_utf16be_str_empty(joliet->application_id, sizeof(joliet->application_id)) || (joliet->application_id[0] == 0x00 && joliet->application_id[1] == '_')); + if (!is_unicode_empty && !is_ascii_empty && (len = merge_utf16be_ascii(buf, joliet->application_id, pvd->application_id, sizeof(pvd->application_id))) != 0) + blkid_probe_set_utf8_id_label(pr, "APPLICATION_ID", buf, len, UL_ENCODE_UTF16BE); + else if (!is_unicode_empty) + blkid_probe_set_utf8_id_label(pr, "APPLICATION_ID", joliet->application_id, sizeof(joliet->application_id), UL_ENCODE_UTF16BE); + else if (!is_ascii_empty) + blkid_probe_set_id_label(pr, "APPLICATION_ID", pvd->application_id, sizeof(pvd->application_id)); + + /* create an UUID using the modified/created date */ + if (! probe_iso9660_set_uuid(pr, &pvd->modified)) + probe_iso9660_set_uuid(pr, &pvd->created); + + if (boot) + blkid_probe_set_id_label(pr, "BOOT_SYSTEM_ID", + boot->boot_system_id, + sizeof(boot->boot_system_id)); + + if (joliet) + blkid_probe_set_version(pr, "Joliet Extension"); + + /* Label in Joliet is UNICODE (UTF16BE) but can contain only 16 characters. Label in PVD is + * subset of ASCII but can contain up to the 32 characters. Non-representable characters are + * stored as replacement character '_'. Label in Joliet is in most cases trimmed but UNICODE + * version of label in PVD. Based on these facts try to reconstruct original label if label + * in Joliet is prefix of the label in PVD (ignoring non-representable characters). + */ + if (joliet && (len = merge_utf16be_ascii(buf, joliet->volume_id, pvd->volume_id, sizeof(pvd->volume_id))) != 0) + blkid_probe_set_utf8label(pr, buf, len, UL_ENCODE_UTF16BE); + else if (joliet) + blkid_probe_set_utf8label(pr, joliet->volume_id, sizeof(joliet->volume_id), UL_ENCODE_UTF16BE); + else + blkid_probe_set_label(pr, pvd->volume_id, sizeof(pvd->volume_id)); + + return 0; +} + +const struct blkid_idinfo iso9660_idinfo = +{ + .name = "iso9660", + .usage = BLKID_USAGE_FILESYSTEM, + .probefunc = probe_iso9660, + .flags = BLKID_IDINFO_TOLERANT, + .magics = + { + { .magic = "CD001", .len = 5, .kboff = 32, .sboff = 1, .hoff = "session_offset" }, + { .magic = "CDROM", .len = 5, .kboff = 32, .sboff = 9, .hoff = "session_offset" }, + { NULL } + } +}; + |