[PHP 5.5 Summit] PHP 5.5: The New Bits (php[architect])

Besides the specifically object-oriented features that have been added, lots of other new functions and extensions have been added as well. In this session, we will cover the new password hashing methods, new uses of empty, updates to how foreach works, password hashing, and more.

Transcript

1. PHP 5.5
   The New Bits
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2. •Community Engineer at Engine Yard
   •Author of Zend PHP 5 Certification
   Study Guide, Sitepoints PHP
   Anthology: 101 Essential Tips, Tricks
   & Hacks & PHP Master: Write
   Cutting Edge Code
   •A contributor to Zend Framework,
   phpdoc, FRAPI and PHP internals
   •@dshafik
   Davey Shafik
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3. About These Slides
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4. About These Slides
   • Two slides per “slide”
   • Title Slide (for when I’m talking)
   • Details slide (for later)
   • Nobody likes it when you can read the slide just as
   well as the speaker can
   • I like slides that are useful
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5. The Small Stuff
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6. The Small Stuff
   • PCRE (Perl Compatible Regular Expression) /e (eval) pattern modifier
   deprecated
   • ext/mysql is now officially deprecated
   • mcrypt_ecb(), mcrypt_cbc(), mcrypt_cfb() and mcrypt_ofb()
   deprecated
   • Drop Windows XP and 2003 support
   • Remove php_logo_guid(), php_egg_logo_guid(),
   php_real_logo_guid(), zend_logo_guid()
   • Return previous handler when passing NULL to set_error_handler()
   and set_exception_handler()
   • Added optional second argument for assert() to specify custom
   message
   • Added boolval() 6
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7. The Small Stuff (Cont.)
   • Added support for PBKDF2: hash_pbkdf2()
   • json_encode() now supports a depth parameter (third argument)
   • Enhancements to GD extension: imageflip(), support for WebP format
   and easy cropping using imagecrop() and imagecropauto()
   • foreach now supports non-scalar keys (as possibly returned by
   Iterators)
   • Zend OpCache now included. Recommended over APC
   • PECL ext/APCu released to provide 100% backwards compatible APC
   User Storage
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8. The Small Stuff (Cont.)
   intlcal_get_keyword_values_for_locale()
   intlcal_get_now()
   intlcal_get_available_locales()
   intlcal_get()
   intlcal_get_time()
   intlcal_set_time()
   intlcal_add()
   intlcal_set_time_zone()
   intlcal_after()
   intlcal_before()
   intlcal_set()
   intlcal_roll()
   intlcal_clear()
   intlcal_field_difference()
   intlcal_get_actual_maximum()
   intlcal_get_actual_minimum()
   intlcal_get_day_of_week_type()
   intlcal_get_first_day_of_week()
   intlcal_get_greatest_minimum()
   intlcal_get_least_maximum()
   intlcal_get_locale()
   intlcal_get_maximum()
   intlcal_get_minimal_days_in_first_week()
   intlcal_get_minimum()
   intlcal_get_time_zone()
   intlcal_get_type()
   intlcal_get_weekend_transition()
   intlcal_in_daylight_time()
   intlcal_is_equivalent_to()
   intlcal_is_lenient()
   intlcal_is_set()
   intlcal_is_weekend()
   intlcal_set_first_day_of_week()
   intlcal_set_lenient()
   intlcal_equals()
   intlcal_get_repeated_wall_time_option()
   intlcal_get_skipped_wall_time_option()
   intlcal_set_repeated_wall_time_option()
   intlcal_set_skipped_wall_time_option()
   intlcal_from_date_time()
   intlcal_to_date_time()
   intlcal_get_error_code()
   intlcal_get_error_message()
   intlgregcal_create_instance()
   intlgregcal_set_gregorian_change()
   intlgregcal_get_gregorian_change()
   intlgregcal_is_leap_year()
   intltz_create_time_zone()
   intltz_create_default()
   intltz_get_id()
   intltz_get_gmt()
   intltz_get_unknown()
   intltz_create_enumeration()
   intltz_count_equivalent_ids()
   intltz_create_time_zone_id_enumeration()
   intltz_get_canonical_id()
   intltz_get_region()
   intltz_get_tz_data_version()
   intltz_get_equivalent_id()
   intltz_use_daylight_time()
   intltz_get_offset()
   intltz_get_raw_offset()
   intltz_has_same_rules()
   intltz_get_display_name()
   intltz_get_dst_savings()
   intltz_from_date_time_zone()
   intltz_to_date_time_zone()
   intltz_get_error_code()
   intltz_get_error_message()
   datefmt_format_object()
   datefmt_get_calendar_object()
   datefmt_get_timezone()
   datefmt_set_timezone()
   datefmt_get_calendar_object()
   intlcal_create_instance()
   Tons of new ext/intl changes (75 new functions!)
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9. boolval()
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10. More on boolval()
    • Identical to: (bool) $var
    • Returns false for empty arrays and strings, and
    zero.
    • Everything else returns true (except false!)
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    var_dump(boolval([]));
    bool(false)
    var_dump(boolval(""));
    bool(false)
    var_dump(boolval(new stdClass()));
    bool(true)
    var_dump(boolval(["foo", "bar"]);
    bool(true)
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11. NULL with
    set_(error|exception)_handler
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12. More on set_(error|exception)_handler
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    • Passing NULL sets the handler to default
    var_dump(set_error_handler(function()  {  }));
       NULL
     
    var_dump(set_error_handler(null));
       object(Closure)#1  (0)  {
       }
     
    var_dump(set_error_handler(null));
       NULL
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13. assert() Descriptions
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14. More on assert()
    • New argument to provide a description of failure
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    assert_options(ASSERT_ACTIVE, IS_ASSERT_ACTIVE);
    function foo($bar, $bat) {
    assert(
    $bar < $bat,
    "Second arg is more than first"
    );'
    }
    foo(2, 1);
    Warning: assert(): Second arg is less than first
    failed in on line
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15. list() support in foreach
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16. list() support in foreach
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    • Allows assignment of nested array values (1st level)
    to multiple variables, within the foreach declaration
    $result = [
    [
    'name' => 'Davey Shafik',
    'email' => 'davey@engineayrd.com',
    ],
    [
    'name' => 'Helgi Þormar Þorbjörnsson',
    'email' => 'helgi@engineyard.com',
    ]
    ];
    foreach ($result as list($name, $email)) {
    echo $name, ': ', $email . PHP_EOL;
    }
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17. empty() supports any expression
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18. empty() supports any expression
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    • Prior to 5.5, empty() only allowed variables as input.
    Now it can be called on any expression, e.g. function
    calls
    if (empty(some_function()) {
    // Do something
    }
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19. String/Array Dereferencing
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20. String/Array Dereferencing
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    • PHP 5.4 added support for function dereferencing,
    5.5 adds the same feature to constant strings and
    arrays
    // Added in PHP 5.4:
    someFunction()[$key];
    // Now available in PHP 5.5
    "somestring"[$key];
    // And:
    ["foo", "bar", "baz"][$key];
    // Note: $key can be any valid expression!
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21. String/Array Dereferencing
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    • Possible use case: randomizing data
    // Random(-ish) Greeting:
    $hi = ["Hi", "Hello", "Hola"][rand(0,2)];
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22. Simple Password Hashing
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23. Simple Password Hashing
    • Makes password hashing super easy
    • Purpose: to make sure everyone uses safe password
    storage
    • Uses the excellent bcrypt (currently)
    • Salting is automatic, but can be supplied
    • The resulting hash itself identifies the algorithm, salt
    and options options when passed to
    password_verify()
    • You may pass an array with salt and cost as third
    argument to password_hash()
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24. Simple Password Hashing (cont.)
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    $options = [
    'cost' => 20,
    'salt' => 'bcryptuses22characters'
    ];
    $hash = password_hash("testing", PASSWORD_DEFAULT, $options);
    $hash = password_hash("testing", PASSWORD_DEFAULT);
    if (password_verify("testing", $hash)) {
    // valid
    }
    Specify Options:
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25. PASSWORD_DEFAULT
    • Default hashing algorithm
    • Currently bcrypt
    • Will change over time to whatever is newer, stronger
    • Recommend that DB columns are 255 chars, as the length may
    change from the current 60 chars with bcrypt
    • Combine with password_needs_rehash() for
    better security
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26. Simple Password Hashing (cont.)
    • Also provides two helper functions:
    • password_needs_rehash() will determine if the hash uses
    the current algorithm, cost and salt, returning true if it doesn’t
    match.
    • password_get_info() returns an array providing information
    about a hash such as algorithm, cost and salt.
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27. password_needs_rehash()
    if (password_verify("testing", $hash)) {
    // valid
    if (password_needs_rehash("testing", PASSWORD_DEFAULT)) {
    // re-hash with password_hash() and store
    }
    }
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28. More on password security
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29. More on password security
    • A strong salt makes a dictionary attack much more
    difficult
    • A high cost means it takes a long time (say, 1/10th
    second) to generate a single password, making brute
    force attacks too slow to be effective
    • The cost is what makes SHA-1 and MD5 poor
    options because they are designed to be fast, this is
    the enemy of security.
    • Additionally, MD5 suffers from too many easy
    collisions (e.g. two different strings that create the
    same hash)
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    Goal: Make both dictionary and brute force attacks difficult.
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30. Hashing Rates
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    Algorithm
    Hashes/
    second
    MD5 SHA-1 SHA-512 bcrypt
    MD5
    180 Billion/
    second
    65% Faster
    99.9997%
    Faster
    99.9999996%
    Faster
    SHA-1
    63 Billion/
    second
    185% Slower
    99.9994%
    Faster
    99.999887%
    Faster
    SHA-512
    364,000/
    second
    49.5M%
    Slower
    17.3M%
    Slower
    80.49%
    Faster
    bcrypt
    71,000/
    second
    253.5M%
    Slower
    88.7M%
    Slower
    412% Slower
    Data Source: http://passwords12.at.ifi.uio.no/
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31. Thank You
    Feedback:
    http://joind.in/9288
    Twitter: @dshafik
    Email: davey@engineyard.com
    Slides:
    http://daveyshafik.com/slides
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