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fortuna/urandom_entropy_src.cpp

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#ifndef FORTUNA_URANDOM_ENTROPY_SRC_CPP
#define FORTUNA_URANDOM_ENTROPY_SRC_CPP
#include "urandom_entropy_src.h"
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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#include "event_adder_impl.h"
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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#include <cassert>
#include <climits>
#include <cstdint>
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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#include <cstring>
#include <mutex>
#include <stdexcept>
#include <vector>
namespace fortuna {
namespace accumulator {
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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auto UrandomEntropySrc::event(accumulator::EventAdderImpl& adder) -> void {
std::lock_guard<std::mutex> lg(mtx);
std::ifstream file;
file.exceptions(std::ifstream::failbit | std::ifstream::badbit);
try {
std::ifstream urandom("/dev/urandom", std::ios::in | std::ios::binary);
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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// how much to get at once
static constexpr const unsigned int this_many_bytes{32};
this->bytes.resize(this_many_bytes);
assert((bytes.size()) == this_many_bytes);
// check if stream is open
if (urandom) {
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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fmt::print(stderr, "[i] ues: /dev/urandom stream open\n");
std::unique_lock<std::mutex> ul;
urandom.read(&this->bytes.front(), this_many_bytes);
urandom.close();
}
else {
// open failed
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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const std::string msg{"\t[!] Failed to open /dev/urandom\n"};
fmt::print(stderr, "{}", msg);
throw std::runtime_error(msg);
}
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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adder.add(this->bytes);
std::memset(this->bytes.data(), 0x00, this->bytes.size()); // clear out
}
catch (std::ifstream::failure& e) {
// FIXME: handle the exception
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fmt::print(stderr, "io exception caugth: {}\n", e.what());
throw;
}
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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catch (std::exception& e) {
// FIXME: handle the exception
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fmt::print(stderr, "[!] ues: exception caugth: {}\n", e.what());
throw;
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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}
}
feat: "prepare to add proper entropy source" nits general * make greater use of "this" Fortuna * declare da_pools as a proper std::array of 32 Pool objects * declare da_pools as const * use std::shared_ptr _p_pools to access da_pools and share access to it * reflect change of pools[] -> std::array in how the array elements are accessed, which is a) via _p_pools pointer and b) using ".at(i)" function * pass _p_pools shared_ptr to Accumulator * refactor member function names and variable names * add member function attribute [[optimize_for_synchronized]] * secure conversions with static_cast-s Accumulator * make use of _p_pools * add _p_pools-related member functions * add a static constexpr variable NUM_OF_POOLS UrandomEntropySrc * implement event adding logic using _p_pools * make std::vector<char> non-static in urandom_entropy_src * implement proper urandom entropy source event "sourcing" (from /dev/urandom), event adding, clear bytes array at the end * properly convert using reinterpret_cast * protect access to the main function with std::lock_guard * receive EventAdderImpl as a ref * use return value from "add_entropy()" member function and create sanity guard checking the return code "int ret" EventAdder * pass event (std::vector<char>) by const& EventAdderImpl * make use of _p_pools shared_ptr * implement proper pool-rotating event-adding logic Pool * delete all copy constructors and assignment operator, the objects will not be copied or assigned to * receive parameters by const& where possible/sensible * handle concurrency: * declare std:string s as mutable * declare a rw std::mutex intended for writing and mutable std::recursive_mutex for read-only operations in const member functions ref: https://herbsutter.com/2013/05/24/gotw-6a-const-correctness-part-1-3/ ref: https://arne-mertz.de/2017/10/mutable/ * use std::lock_guard and std::unique_lock * refactor "add_entropy()" member function * get rid of intermediate "event_str" and directly use the "event" std::vector<char> for all operations * add a lock guard to prevent multiple threads (should that route be taken) from modifying pool resources simultaneously * add all_ok bool for basic sanity checking * add print statements (at least for now) * rename "get_s_length()" member function to "get_s_byte_count()" and repurpose it to return byte count of the stored entropy std::string s
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UrandomEntropySrc::UrandomEntropySrc() : EntropySrc::EntropySrc() {}
UrandomEntropySrc::~UrandomEntropySrc() noexcept {}
} // namespace accumulator
} // namespace fortuna
#endif // FORTUNA_URANDOM_ENTROPY_SRC_CPP