libsodium_crypto_pwhash_scryptsalsa208sha256 (libsodium v3.0.1)
View SourcePassword hashing and password-based key derivation with scrypt
(scryptsalsa208sha256). Prefer Argon2id through
libsodium_crypto_pwhash for new applications; use scrypt for
interoperability with existing scrypt hashes or keys.
str/3 produces a self-describing $7$ string to store and check with
str_verify/2; crypto_pwhash_scryptsalsa208sha256/5 derives a key from a
password and a saltbytes/0 byte salt, and ll/6 exposes the raw scrypt
function with explicit N, R, and P parameters. Raise Opslimit and
Memlimit (memory in bytes) as far as your latency budget allows, starting
from the _interactive limits for online logins; libsodium raises values
below the minimums to the minimums. All hashing runs on a dirty CPU
scheduler.
Ops = libsodium_crypto_pwhash_scryptsalsa208sha256:opslimit_interactive(),
Mem = libsodium_crypto_pwhash_scryptsalsa208sha256:memlimit_interactive(),
Str = libsodium_crypto_pwhash_scryptsalsa208sha256:str(<<"correct horse">>, Ops, Mem),
0 = libsodium_crypto_pwhash_scryptsalsa208sha256:str_verify(Str, <<"correct horse">>),
-1 = libsodium_crypto_pwhash_scryptsalsa208sha256:str_verify(Str, <<"wrong horse">>),
0 = libsodium_crypto_pwhash_scryptsalsa208sha256:str_needs_rehash(Str, Ops, Mem).Summary
Functions
Return crypto_pwhash_scryptsalsa208sha256_bytes_max(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_bytes_min(), in bytes.
Derive an Outlen byte key from Passwd and the saltbytes/0 byte
Salt with the cost parameters Opslimit and Memlimit.
Compute raw scrypt over Passwd and Salt with the CPU/memory cost
N (a power of two greater than one), block size R, and
parallelism P, producing Buflen bytes.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_interactive(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_max(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_min(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_sensitive(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_interactive(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_max(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_min(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_sensitive(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_passwd_max(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_passwd_min(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_saltbytes(), in bytes.
Hash Passwd for storage with the cost parameters Opslimit and
Memlimit and a random salt.
Check whether Str was hashed with exactly the parameters that
Opslimit and Memlimit select.
Check Passwd against Str, a $7$ string produced by str/3.
Return crypto_pwhash_scryptsalsa208sha256_strbytes(), in bytes.
Return crypto_pwhash_scryptsalsa208sha256_strprefix() as a binary.
Types
Functions
-spec bytes_max() -> Result when Result :: non_neg_integer().
Return crypto_pwhash_scryptsalsa208sha256_bytes_max(), in bytes.
-spec bytes_min() -> Result when Result :: 16.
Return crypto_pwhash_scryptsalsa208sha256_bytes_min(), in bytes.
-spec crypto_pwhash_scryptsalsa208sha256(Outlen, Passwd, Salt, Opslimit, Memlimit) -> Result when Outlen :: non_neg_integer(), Passwd :: binary(), Salt :: salt(), Opslimit :: non_neg_integer(), Memlimit :: non_neg_integer(), Result :: binary() | -1.
Derive an Outlen byte key from Passwd and the saltbytes/0 byte
Salt with the cost parameters Opslimit and Memlimit.
Returns -1 when libsodium rejects the parameters (for example an
Outlen below bytes_min/0) or cannot allocate the requested memory.
-spec ll(Passwd, Salt, N, R, P, Buflen) -> Result when Passwd :: binary(), Salt :: binary(), N :: non_neg_integer(), R :: 0..4294967295, P :: 0..4294967295, Buflen :: non_neg_integer(), Result :: binary() | -1.
Compute raw scrypt over Passwd and Salt with the CPU/memory cost
N (a power of two greater than one), block size R, and
parallelism P, producing Buflen bytes.
Returns -1 when the parameters are invalid or the required memory
cannot be allocated.
-spec memlimit_interactive() -> Result when Result :: 16777216.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_interactive(), in bytes.
-spec memlimit_max() -> Result when Result :: non_neg_integer().
Return crypto_pwhash_scryptsalsa208sha256_memlimit_max(), in bytes.
-spec memlimit_min() -> Result when Result :: 16777216.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_min(), in bytes.
-spec memlimit_sensitive() -> Result when Result :: 1073741824.
Return crypto_pwhash_scryptsalsa208sha256_memlimit_sensitive(), in bytes.
-spec opslimit_interactive() -> Result when Result :: 524288.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_interactive(), in bytes.
-spec opslimit_max() -> Result when Result :: 4294967295.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_max(), in bytes.
-spec opslimit_min() -> Result when Result :: 32768.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_min(), in bytes.
-spec opslimit_sensitive() -> Result when Result :: 33554432.
Return crypto_pwhash_scryptsalsa208sha256_opslimit_sensitive(), in bytes.
-spec passwd_max() -> Result when Result :: non_neg_integer().
Return crypto_pwhash_scryptsalsa208sha256_passwd_max(), in bytes.
-spec passwd_min() -> Result when Result :: 0.
Return crypto_pwhash_scryptsalsa208sha256_passwd_min(), in bytes.
-spec saltbytes() -> Result when Result :: 32.
Return crypto_pwhash_scryptsalsa208sha256_saltbytes(), in bytes.
-spec str(Passwd, Opslimit, Memlimit) -> Result when Passwd :: binary(), Opslimit :: non_neg_integer(), Memlimit :: non_neg_integer(), Result :: binary() | -1.
Hash Passwd for storage with the cost parameters Opslimit and
Memlimit and a random salt.
Returns an ASCII binary of strbytes/0 - 1 bytes starting with
strprefix/0, or -1 on failure.
-spec str_needs_rehash(Str, Opslimit, Memlimit) -> Result when Str :: binary(), Opslimit :: non_neg_integer(), Memlimit :: non_neg_integer(), Result :: -1 | 0 | 1.
Check whether Str was hashed with exactly the parameters that
Opslimit and Memlimit select.
Returns 0 when it was, 1 when the password should be rehashed (after
a successful str_verify/2), and -1 when Str is malformed.
Check Passwd against Str, a $7$ string produced by str/3.
Returns 0 when the password matches and -1 when it does not or
Str is malformed.
-spec strbytes() -> Result when Result :: 102.
Return crypto_pwhash_scryptsalsa208sha256_strbytes(), in bytes.
-spec strprefix() -> Result when Result :: binary().
Return crypto_pwhash_scryptsalsa208sha256_strprefix() as a binary.