diff options
| -rw-r--r-- | modules/dev.inc | 152 | ||||
| -rw-r--r-- | modules/regex.inc | 5 |
2 files changed, 137 insertions, 20 deletions
diff --git a/modules/dev.inc b/modules/dev.inc index c2046d3..6080af6 100644 --- a/modules/dev.inc +++ b/modules/dev.inc @@ -8,42 +8,154 @@ # The output will be a list of matching devices, # sorted from largest to smallest. dev_find_partitions() { - local ID dev exp target - exp= + local ID dev target # target for the scan, defaults to /dev to check everything - if [ -b "$1" ]; then + if [ "${1:0:1}" = "/" ] && [ -b "$1" ]; then target="$1" shift - elif [ -d "$1" ]; then + elif [ "${1:0:1}" = "/" ] && [ -d "$1" ]; then target="$1/" + shift else target="/dev/" fi + local want_label="never match this#" + local want_type="never match this#" + local want_uuid="never match this#" while [ "$#" -gt 0 ]; do ID="$1" shift [ -z "$ID" ] && continue - # if single digit, e.g. 7, look for 0x7 and 0x07 if regex_imatch "$ID" "^[0-9a-f]$"; then - ID="0?$ID" - fi - - if regex_imatch "$ID" "^[0-9a-f?]{2,3}$"; then # Match two digit and the expanded three digit version from above - # if double digit look for MBR types and OpenSLX-ID$ID GPT labels - exp="$exp|ID_PART_ENTRY_(NAME=OpenSLX-ID|TYPE=0x)$ID" + want_type="$want_type|0$ID" + want_label="$want_label|OpenSLX-ID0$ID" + elif regex_imatch "$ID" "^[0-9a-f]{2}$"; then + want_type="$want_type|$ID" + want_label="$want_label|OpenSLX-ID$ID" elif regex_imatch "$ID" "^[0-9a-f]{8}-([0-9a-f]{4}-){3}[0-9a-f]{12}$"; then - # if UUID, look for TYPE - exp="$exp|ID_PART_ENTRY_TYPE=$ID" - else - # something else, look for names of partitions / filesystems - ID="$( regex_escape "$ID" )" - exp="$exp|ID_(PART_ENTRY_NAME|FS_LABEL)=$ID" + want_uuid="$want_uuid|$ID" + elif [ "${#ID}" -gt 3 ]; then # Safety measure: Want label length >= 4 chars + want_label="$want_label|$( regex_escape "$ID" )" fi done - exp="${exp:1}" + local label number mbrid uuid for dev in $(find $target* -type b); do - udevadm info --name="$dev" | grep -iqE "($exp)\$" \ - && printf "%s\n" "$(blockdev --getsize64 "$dev") $dev" + dev_get_type "$dev" + if regex_imatch "$mbrid" "^($want_type)$" || regex_imatch "$uuid" "^($want_uuid)$" \ + || regex_match "$label" "^($want_label)$"; then + printf "%s\n" "$(blockdev --getsize64 "$dev") $dev" + fi done | sort -n -k1 -r | cut -d' ' -f2 } +dev_get_type() { + local part dev partn devn pstart + dev= + mbrid= + uuid= + label= + number= + [ -b "$1" ] || return 1 + part="$( readlink -f "$1" )" + partn="${part##*/}" + for devn in "${partn%p?}" "${partn%?}"; do + if [ "$dev" != "$part" ] && [ -f "/sys/block/${devn}/${partn}/uevent" ]; then + dev="/dev/${devn}" + break + fi + done + [ -z "$dev" ] && return 1 + pstart="$( cat "/sys/block/${devn}/${partn}/start" )" # For validation + label="$( grep -Po '(?<=^PARTNAME=).*$' "/sys/block/${devn}/${partn}/uevent" )" + number="$( grep -Po '(?<=^PARTN=).*$' "/sys/block/${devn}/${partn}/uevent" )" + local gpt= + if [ "$( dd if="$dev" bs=1 count=8 skip=512 2> /dev/null )" = "EFI PART" ]; then + gpt=512 + elif [ "$( dd if="$dev" bs=1 count=8 skip=4096 2> /dev/null )" = "EFI PART" ]; then + gpt=4096 + fi + if [ -z "$label" ] && [ "$number" -lt 1000 ] && [ "$number" -gt 0 ] \ + && [ "$( __read_mbrsig "$dev" 0 )" = "55aa" ]; then + # Get MBR ID + if [ "$number" -le 4 ]; then + # Primary + mbrid="$( __read_mbrid "$dev" 0 "$number" )" + else + # Scan for Primary type 05, scan linked list of fake MBRs from there + local no id ex_start log_id log_start next_id next_start current + for no in 1 2 3 4; do + id="$( __read_mbrid "$dev" 0 "$no" )" + echo "Scanning. Primary $no is type $id" >&2 + [ "$id" = "05" ] && break + done + if [ "$id" != "05" ]; then + echo "No matching extended primary partition found" >&2 + return 1 + fi + ex_start="$( __read_mbrstart "$dev" 0 "$no" )" + current="$ex_start" + no=5 # Count through logical partitions + while [ "$no" != 0 ]; do + [ "$( __read_mbrsig "$dev" "$current" )" = "55aa" ] || break + log_id="$( __read_mbrid "$dev" "$current" 1 )" + if [ "$no" = "$number" ]; then + log_start="$( __read_mbrstart "$dev" "$current" 1 )" + log_start="$(( log_start + current ))" + if [ "$pstart" != "$log_start" ]; then + echo "Found partition $no, but start mismatch (want: $pstart found: $log_start)" >&2 + return 1 + fi + mbrid="$log_id" + break + fi + next_id="$( __read_mbrid "$dev" "$current" 2 )" + next_start="$( __read_mbrstart "$dev" "$current" 2 )" + echo "Extended id $log_id, next $next_id, $next_start" >&2 + if [ "$next_id" = "05" ] && [ "$next_start" -gt 0 ]; then + current="$(( next_start + ex_start ))" + no="$(( no + 1 ))" + else + no=0 + fi + done + fi + return 0 + elif [ -n "$gpt" ]; then + # GPT + local table_start current entries no entry_size log_start + table_start="$( __read_le "$dev" "$(( gpt + 72 ))" 8 )" + entries="$( __read_le "$dev" "$(( gpt + 80 ))" 4 )" + entry_size="$( __read_le "$dev" "$(( gpt + 84 ))" 4 )" + current="$(( table_start * gpt ))" + if ! [ "$current" -ge "$(( gpt * 2 ))" ] || ! [ "$entries" -gt 0 ] \ + || [ "$entries" -lt "$number" ] || ! [ "$entry_size" -le 4096 ]; then + echo "Bad GPT table. Start: $current, Partition count: $entries. Want: $number" >&2 + return 1 + fi + log_start="$( __read_le "$dev" "$(( current + entry_size * (number - 1) + 32 ))" 8 )" + if [ "$log_start" != "$pstart" ]; then + echo "Found partition $number, but start mismatch (want: $pstart found: $log_start)" >&2 + return 1 + fi + uuid="$( dd if="$dev" bs=1 count=16 skip="$(( current + entry_size * (number - 1) ))" 2> /dev/null | xxd -p \ + | sed -r 's/^(..)(..)(..)(..)(..)(..)(..)(..)(....)/\4\3\2\1-\6\5-\8\7-\9-/' )" + return 0 + fi +} + +__read_mbrid() { + dd if="$1" bs=1 skip=$(( 512 * $2 + 446 + ($3 - 1) * 16 + 4 )) count=1 2> /dev/null | xxd -p +} + +__read_mbrstart() { + __read_le "$1" "$(( 512 * $2 + 446 + ($3 - 1) * 16 + 8 ))" 4 +} + +__read_mbrsig() { + dd if="$1" bs=1 skip=$(( 512 * $2 + 510 )) count=2 2> /dev/null | xxd -p +} + +__read_le() { + local v="$( dd if="$1" bs=1 count="$3" skip="$2" 2> /dev/null | xxd -e -g "$3" | cut -d' ' -f2 )" + echo $(( 0x$v )) +} diff --git a/modules/regex.inc b/modules/regex.inc index 21c3d65..3188b2d 100644 --- a/modules/regex.inc +++ b/modules/regex.inc @@ -1,5 +1,10 @@ #!/bin/ash +# Match $1 against perl regex $2, case sensitive +regex_match() { + printf "%s" "$1" | grep -qP "$2" +} + # Match $1 against perl regex $2, case insensitive regex_imatch() { printf "%s" "$1" | grep -qPi "$2" |