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/**
* (C) 2019 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/argon2fmt.h>
#include <botan/base64.h>
#include <botan/mem_ops.h>
#include <botan/pwdhash.h>
#include <botan/rng.h>
#include <botan/internal/ct_utils.h>
#include <botan/internal/fmt.h>
#include <botan/internal/parsing.h>
namespace Botan {
namespace {
std::string strip_padding(std::string s) {
while(!s.empty() && s[s.size() - 1] == '=') {
s.resize(s.size() - 1);
}
return s;
}
std::string argon2_family(uint8_t y) {
if(y == 0) {
return "Argon2d";
} else if(y == 1) {
return "Argon2i";
} else if(y == 2) {
return "Argon2id";
} else {
throw Not_Implemented("Unknown Argon2 family type");
}
}
} // namespace
std::string argon2_generate_pwhash(const char* password,
size_t password_len,
RandomNumberGenerator& rng,
size_t p,
size_t M,
size_t t,
uint8_t y,
size_t salt_len,
size_t output_len) {
std::vector<uint8_t> salt(salt_len);
rng.randomize(salt.data(), salt.size());
std::vector<uint8_t> output(output_len);
auto pwdhash_fam = PasswordHashFamily::create_or_throw(argon2_family(y));
auto pwdhash = pwdhash_fam->from_params(M, t, p);
pwdhash->derive_key(output.data(), output.size(), password, password_len, salt.data(), salt.size());
const auto enc_salt = strip_padding(base64_encode(salt));
const auto enc_output = strip_padding(base64_encode(output));
const std::string argon2_mode = [&]() -> std::string {
if(y == 0) {
return "d";
} else if(y == 1) {
return "i";
} else {
return "id";
}
}();
return fmt("$argon2{}$v=19$m={},t={},p={}${}${}", argon2_mode, M, t, p, enc_salt, enc_output);
}
bool argon2_check_pwhash(const char* password, size_t password_len, std::string_view input_hash) {
const std::vector<std::string> parts = split_on(input_hash, '$');
if(parts.size() != 5) {
return false;
}
uint8_t family = 0;
if(parts[0] == "argon2d") {
family = 0;
} else if(parts[0] == "argon2i") {
family = 1;
} else if(parts[0] == "argon2id") {
family = 2;
} else {
return false;
}
if(parts[1] != "v=19") {
return false;
}
const std::vector<std::string> params = split_on(parts[2], ',');
if(params.size() != 3) {
return false;
}
size_t M = 0, t = 0, p = 0;
for(const auto& param_str : params) {
const std::vector<std::string> param = split_on(param_str, '=');
if(param.size() != 2) {
return false;
}
std::string_view key = param[0];
const size_t val = to_u32bit(param[1]);
if(key == "m") {
M = val;
} else if(key == "t") {
t = val;
} else if(key == "p") {
p = val;
} else {
return false;
}
}
std::vector<uint8_t> salt(base64_decode_max_output(parts[3].size()));
salt.resize(base64_decode(salt.data(), parts[3], false));
std::vector<uint8_t> hash(base64_decode_max_output(parts[4].size()));
hash.resize(base64_decode(hash.data(), parts[4], false));
if(hash.size() < 4) {
return false;
}
std::vector<uint8_t> generated(hash.size());
auto pwdhash_fam = PasswordHashFamily::create_or_throw(argon2_family(family));
auto pwdhash = pwdhash_fam->from_params(M, t, p);
pwdhash->derive_key(generated.data(), generated.size(), password, password_len, salt.data(), salt.size());
return CT::is_equal(generated.data(), hash.data(), generated.size()).as_bool();
}
} // namespace Botan