SQL Engine

💉jSQL generates default SQL syntax based on a template which is editable in tab SQL Engine, allowing to live-debug and optimize queries on the fly for current identified engine.

Any SQL part is defined by a unique ${tag} and all tags are replaced by its concrete value in the final query.

The entire template is roughly like the following:

character insertion layer                                    # input prefix
  ${indices}:Union or ${binary.mode} & ${test}:Time+Blind    # strategy layer
    ${window}                                                # chars substring
      ${window.char}:Multibit+Bittest & ${bit}               # chars position index
        ${injection}:all                                     # main select
          ${database} ${table} ${fields}                     # all fields with main from
            ${field.value}                                   # field syntax
              ${indice} & ${calibrator}                      # Union specific
          ${limit}                                           # rows index
            ${limit.value}                                   # substring index

Eg. Template applied to Union sample:

...&name=2212100212                                          # input prefix
  union select 1,1,1,1,(                                     # strategy layer
    select concat(0x53714c69,ifnull(
      mid((                                                  # chars substring
        select group_concat(0x04,r,0x05,q,0x04 order by r separator 0x06)  # main select
        from(                                                # all fields with main from
          select schema_name r,count(table_name)q            # field syntax
          from information_schema.tables 
          right join information_schema.schemata on schema_name=table_schema 
          group by r order by 1 
          limit 0,65536                                      # rows index
        )x
      ),1,65537)
    ,''),0x01030307)
  ),1,1-- -I0Hq

Structure — schema content — ${injection}

• Database: get names with number of tables
• Tables: get names with number of rows
• Columns: get names
• Rows: get de-duplicated rows
  • Field: single column name, all fields are concatenated into ${fields} with separator
  • Field Separator: added between fields to separate column values
• Metadata: get engine info like version and current user

Strategy — high level syntax

• Union: apply union-based select
• Stack: apply stack query
• Error: apply exception trigger that includes the result
• Binary — bitwise strategies
  • Mode — ${binary.mode}: use AND/OR depending on the initial query state (eg. where 1=1 AND, where 1=0 OR)
  • Blind: get result Yes/No for given bit from ASCII code of a single char
  • Time: get delay Yes/No for given bit from ASCII code of a single char
  • Multibit: get specific result for given bits from ASCII code of a single char
  • Bit test — ${test}: return true when the bit of given ASCII code is 1, else return false

Configuration — other parts

• Char Sliding Window — ${window.char}: set a substring of data
• Rows Sliding Window — ${limit}: set rows starting at specific position (see LIMIT)
• Limit start index — ${limit.value}: set LIMIT initial position, some engine starts at 0 and some at 1
• Capacity — ${capacity}: set specific Union query to measure indexes response size
• Calibrator — ${calibrator}: repeat given char for Union capacity measure
• Failsafe: set Union index with N0+1 form
• End comment: set SQL comment to ignore internal query remaining parts

Fingerprint — identify engine and character insertion

• Order by: set wrong column index to trigger specific engine error
• Order by error: expected engine error when order by index is wrong
• String error: expected SQL syntax error when query is incorrect
• Truthy: list of predicate checked as true by engine
• Falsy: list of predicate checked as false by engine

File

• Privilege: get current user's read permission
• Read: get file content to read
• Write body: set file content to write
• Write path: set file path to write

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