Botan 3.9.0
Crypto and TLS for C&
Botan::TOTP Class Referencefinal

#include <otp.h>

Public Member Functions

uint32_t generate_totp (std::chrono::system_clock::time_point time_point)
uint32_t generate_totp (uint64_t unix_time)
BOTAN_FUTURE_EXPLICIT TOTP (const SymmetricKey &key, std::string_view hash_algo="SHA-1", size_t digits=6, size_t time_step=30)
 TOTP (const uint8_t key[], size_t key_len, std::string_view hash_algo="SHA-1", size_t digits=6, size_t time_step=30)
bool verify_totp (uint32_t otp, std::chrono::system_clock::time_point time, size_t clock_drift_accepted=0)
bool verify_totp (uint32_t otp, uint64_t unix_time, size_t clock_drift_accepted=0)

Detailed Description

TOTP (time based) one time passwords (RFC 6238)

Definition at line 64 of file otp.h.

Constructor & Destructor Documentation

◆ TOTP() [1/2]

BOTAN_FUTURE_EXPLICIT Botan::TOTP::TOTP ( const SymmetricKey & key,
std::string_view hash_algo = "SHA-1",
size_t digits = 6,
size_t time_step = 30 )
inline
Parameters
keythe secret key shared between client and server
hash_algothe hash algorithm to use, should be SHA-1, SHA-256 or SHA-512
digitsthe number of digits in the OTP (must be 6, 7, or 8)
time_stepgranularity of OTP in seconds

Definition at line 72 of file otp.h.

75 :
76 TOTP(key.begin(), key.size(), hash_algo, digits, time_step) {}
BOTAN_FUTURE_EXPLICIT TOTP(const SymmetricKey &key, std::string_view hash_algo="SHA-1", size_t digits=6, size_t time_step=30)
Definition otp.h:72

References BOTAN_FUTURE_EXPLICIT, and TOTP().

Referenced by TOTP().

◆ TOTP() [2/2]

Botan::TOTP::TOTP ( const uint8_t key[],
size_t key_len,
std::string_view hash_algo = "SHA-1",
size_t digits = 6,
size_t time_step = 30 )
Parameters
keythe secret key shared between client and server
key_lenlength of key
hash_algothe hash algorithm to use, should be SHA-1, SHA-256 or SHA-512
digitsthe number of digits in the OTP (must be 6, 7, or 8)
time_stepgranularity of OTP in seconds

Definition at line 15 of file totp.cpp.

15 :
16 m_hotp(key, key_len, hash_algo, digits),
17 m_time_step(time_step),
18 m_unix_epoch(calendar_point(1970, 1, 1, 0, 0, 0).to_std_timepoint()) {
19 /*
20 * Technically any time step except 0 is valid, but 30 is typical
21 * and over 5 minutes seems unlikely.
22 */
23 BOTAN_ARG_CHECK(m_time_step > 0 && m_time_step < 300, "Invalid TOTP time step");
24}
#define BOTAN_ARG_CHECK(expr, msg)
Definition assert.h:33

References BOTAN_ARG_CHECK.

Member Function Documentation

◆ generate_totp() [1/2]

uint32_t Botan::TOTP::generate_totp ( std::chrono::system_clock::time_point time_point)

Convert the provided time_point to a Unix timestamp and call generate_totp

Definition at line 26 of file totp.cpp.

26 {
27 const uint64_t unix_time = std::chrono::duration_cast<std::chrono::seconds>(current_time - m_unix_epoch).count();
28 return this->generate_totp(unix_time);
29}
uint32_t generate_totp(std::chrono::system_clock::time_point time_point)
Definition totp.cpp:26

References generate_totp().

Referenced by generate_totp().

◆ generate_totp() [2/2]

uint32_t Botan::TOTP::generate_totp ( uint64_t unix_time)

Generate the OTP corresponding the the provided "Unix timestamp" (ie number of seconds since midnight Jan 1, 1970)

Definition at line 31 of file totp.cpp.

31 {
32 return m_hotp.generate_hotp(unix_time / m_time_step);
33}

◆ verify_totp() [1/2]

bool Botan::TOTP::verify_totp ( uint32_t otp,
std::chrono::system_clock::time_point time,
size_t clock_drift_accepted = 0 )

Definition at line 35 of file totp.cpp.

35 {
36 const uint64_t unix_time = std::chrono::duration_cast<std::chrono::seconds>(current_time - m_unix_epoch).count();
37 return verify_totp(otp, unix_time, clock_drift_accepted);
38}
bool verify_totp(uint32_t otp, std::chrono::system_clock::time_point time, size_t clock_drift_accepted=0)
Definition totp.cpp:35

References verify_totp().

Referenced by verify_totp().

◆ verify_totp() [2/2]

bool Botan::TOTP::verify_totp ( uint32_t otp,
uint64_t unix_time,
size_t clock_drift_accepted = 0 )

Definition at line 40 of file totp.cpp.

40 {
41 uint64_t t = unix_time / m_time_step;
42
43 for(size_t i = 0; i <= clock_drift_accepted; ++i) {
44 if(m_hotp.generate_hotp(t - i) == otp) {
45 return true;
46 }
47 }
48
49 return false;
50}

The documentation for this class was generated from the following files: