| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/git/checkouts/incubator-teaclave-crates-c8106113f74feefc/ede1f68/ring/src/hmac.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>hmac.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../ring/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../ring/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="comment">// Copyright 2015-2016 Brian Smith. |
| // |
| // Permission to use, copy, modify, and/or distribute this software for any |
| // purpose with or without fee is hereby granted, provided that the above |
| // copyright notice and this permission notice appear in all copies. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES |
| // WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| // MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY |
| // SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| // WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION |
| // OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN |
| // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| |
| </span><span class="doccomment">//! HMAC is specified in [RFC 2104]. |
| //! |
| //! After a `Key` is constructed, it can be used for multiple signing or |
| //! verification operations. Separating the construction of the key from the |
| //! rest of the HMAC operation allows the per-key precomputation to be done |
| //! only once, instead of it being done in every HMAC operation. |
| //! |
| //! Frequently all the data to be signed in a message is available in a single |
| //! contiguous piece. In that case, the module-level `sign` function can be |
| //! used. Otherwise, if the input is in multiple parts, `Context` should be |
| //! used. |
| //! |
| //! # Examples: |
| //! |
| //! ## Signing a value and verifying it wasn't tampered with |
| //! |
| //! ``` |
| //! use ring::{hmac, rand}; |
| //! |
| //! let rng = rand::SystemRandom::new(); |
| //! let key = hmac::Key::generate(hmac::HMAC_SHA256, &rng)?; |
| //! |
| //! let msg = "hello, world"; |
| //! |
| //! let tag = hmac::sign(&key, msg.as_bytes()); |
| //! |
| //! // [We give access to the message to an untrusted party, and they give it |
| //! // back to us. We need to verify they didn't tamper with it.] |
| //! |
| //! hmac::verify(&key, msg.as_bytes(), tag.as_ref())?; |
| //! |
| //! # Ok::<(), ring::error::Unspecified>(()) |
| //! ``` |
| //! |
| //! ## Using the one-shot API: |
| //! |
| //! ``` |
| //! use ring::{digest, hmac, rand}; |
| //! use ring::rand::SecureRandom; |
| //! |
| //! let msg = "hello, world"; |
| //! |
| //! // The sender generates a secure key value and signs the message with it. |
| //! // Note that in a real protocol, a key agreement protocol would be used to |
| //! // derive `key_value`. |
| //! let rng = rand::SystemRandom::new(); |
| //! let key_value: [u8; digest::SHA256_OUTPUT_LEN] = rand::generate(&rng)?.expose(); |
| //! |
| //! let s_key = hmac::Key::new(hmac::HMAC_SHA256, key_value.as_ref()); |
| //! let tag = hmac::sign(&s_key, msg.as_bytes()); |
| //! |
| //! // The receiver (somehow!) knows the key value, and uses it to verify the |
| //! // integrity of the message. |
| //! let v_key = hmac::Key::new(hmac::HMAC_SHA256, key_value.as_ref()); |
| //! hmac::verify(&v_key, msg.as_bytes(), tag.as_ref())?; |
| //! |
| //! # Ok::<(), ring::error::Unspecified>(()) |
| //! ``` |
| //! |
| //! ## Using the multi-part API: |
| //! ``` |
| //! use ring::{digest, hmac, rand}; |
| //! use ring::rand::SecureRandom; |
| //! |
| //! let parts = ["hello", ", ", "world"]; |
| //! |
| //! // The sender generates a secure key value and signs the message with it. |
| //! // Note that in a real protocol, a key agreement protocol would be used to |
| //! // derive `key_value`. |
| //! let rng = rand::SystemRandom::new(); |
| //! let mut key_value: [u8; digest::SHA384_OUTPUT_LEN] = rand::generate(&rng)?.expose(); |
| //! |
| //! let s_key = hmac::Key::new(hmac::HMAC_SHA384, key_value.as_ref()); |
| //! let mut s_ctx = hmac::Context::with_key(&s_key); |
| //! for part in &parts { |
| //! s_ctx.update(part.as_bytes()); |
| //! } |
| //! let tag = s_ctx.sign(); |
| //! |
| //! // The receiver (somehow!) knows the key value, and uses it to verify the |
| //! // integrity of the message. |
| //! let v_key = hmac::Key::new(hmac::HMAC_SHA384, key_value.as_ref()); |
| //! let mut msg = Vec::<u8>::new(); |
| //! for part in &parts { |
| //! msg.extend(part.as_bytes()); |
| //! } |
| //! hmac::verify(&v_key, &msg.as_ref(), tag.as_ref())?; |
| //! |
| //! # Ok::<(), ring::error::Unspecified>(()) |
| //! ``` |
| //! |
| //! [RFC 2104]: https://tools.ietf.org/html/rfc2104 |
| //! [code for `ring::pbkdf2`]: |
| //! https://github.com/briansmith/ring/blob/main/src/pbkdf2.rs |
| //! [code for `ring::hkdf`]: |
| //! https://github.com/briansmith/ring/blob/main/src/hkdf.rs |
| |
| </span><span class="kw">use crate</span>::{constant_time, digest, error, hkdf, rand}; |
| |
| <span class="doccomment">/// An HMAC algorithm. |
| </span><span class="attribute">#[derive(Clone, Copy, Debug, PartialEq, Eq)] |
| </span><span class="kw">pub struct </span>Algorithm(<span class="kw-2">&</span><span class="lifetime">'static </span>digest::Algorithm); |
| |
| <span class="kw">impl </span>Algorithm { |
| <span class="doccomment">/// The digest algorithm this HMAC algorithm is based on. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>digest_algorithm(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span><span class="lifetime">'static </span>digest::Algorithm { |
| <span class="self">self</span>.<span class="number">0 |
| </span>} |
| } |
| |
| <span class="doccomment">/// HMAC using SHA-1. Obsolete. |
| </span><span class="kw">pub static </span>HMAC_SHA1_FOR_LEGACY_USE_ONLY: Algorithm = Algorithm(<span class="kw-2">&</span>digest::SHA1_FOR_LEGACY_USE_ONLY); |
| |
| <span class="doccomment">/// HMAC using SHA-256. |
| </span><span class="kw">pub static </span>HMAC_SHA256: Algorithm = Algorithm(<span class="kw-2">&</span>digest::SHA256); |
| |
| <span class="doccomment">/// HMAC using SHA-384. |
| </span><span class="kw">pub static </span>HMAC_SHA384: Algorithm = Algorithm(<span class="kw-2">&</span>digest::SHA384); |
| |
| <span class="doccomment">/// HMAC using SHA-512. |
| </span><span class="kw">pub static </span>HMAC_SHA512: Algorithm = Algorithm(<span class="kw-2">&</span>digest::SHA512); |
| |
| <span class="doccomment">/// A deprecated alias for `Tag`. |
| </span><span class="attribute">#[deprecated(note = <span class="string">"`Signature` was renamed to `Tag`. This alias will be removed soon."</span>)] |
| </span><span class="kw">pub type </span>Signature = Tag; |
| |
| <span class="doccomment">/// An HMAC tag. |
| /// |
| /// For a given tag `t`, use `t.as_ref()` to get the tag value as a byte slice. |
| </span><span class="attribute">#[derive(Clone, Copy, Debug)] |
| </span><span class="kw">pub struct </span>Tag(digest::Digest); |
| |
| <span class="kw">impl </span>AsRef<[u8]> <span class="kw">for </span>Tag { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>as_ref(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8] { |
| <span class="self">self</span>.<span class="number">0</span>.as_ref() |
| } |
| } |
| |
| <span class="doccomment">/// A key to use for HMAC signing. |
| </span><span class="attribute">#[derive(Clone)] |
| </span><span class="kw">pub struct </span>Key { |
| inner: digest::BlockContext, |
| outer: digest::BlockContext, |
| } |
| |
| <span class="doccomment">/// `hmac::SigningKey` was renamed to `hmac::Key`. |
| </span><span class="attribute">#[deprecated(note = <span class="string">"Renamed to `hmac::Key`."</span>)] |
| </span><span class="kw">pub type </span>SigningKey = Key; |
| |
| <span class="doccomment">/// `hmac::VerificationKey` was merged into `hmac::Key`. |
| </span><span class="attribute">#[deprecated( |
| note = <span class="string">"The distinction between verification & signing keys was removed. Use `hmac::Key`." |
| </span>)] |
| </span><span class="kw">pub type </span>VerificationKey = Key; |
| |
| <span class="kw">impl </span>core::fmt::Debug <span class="kw">for </span>Key { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, f: <span class="kw-2">&mut </span>core::fmt::Formatter) -> <span class="prelude-ty">Result</span><(), core::fmt::Error> { |
| f.debug_struct(<span class="string">"Key"</span>) |
| .field(<span class="string">"algorithm"</span>, <span class="self">self</span>.algorithm().digest_algorithm()) |
| .finish() |
| } |
| } |
| |
| <span class="kw">impl </span>Key { |
| <span class="doccomment">/// Generate an HMAC signing key using the given digest algorithm with a |
| /// random value generated from `rng`. |
| /// |
| /// The key will be `digest_alg.output_len` bytes long, based on the |
| /// recommendation in [RFC 2104 Section 3]. |
| /// |
| /// [RFC 2104 Section 3]: https://tools.ietf.org/html/rfc2104#section-3 |
| </span><span class="kw">pub fn </span>generate( |
| algorithm: Algorithm, |
| rng: <span class="kw-2">&</span><span class="kw">dyn </span>rand::SecureRandom, |
| ) -> <span class="prelude-ty">Result</span><<span class="self">Self</span>, error::Unspecified> { |
| <span class="self">Self</span>::construct(algorithm, |buf| rng.fill(buf)) |
| } |
| |
| <span class="kw">fn </span>construct<F>(algorithm: Algorithm, fill: F) -> <span class="prelude-ty">Result</span><<span class="self">Self</span>, error::Unspecified> |
| <span class="kw">where |
| </span>F: FnOnce(<span class="kw-2">&mut </span>[u8]) -> <span class="prelude-ty">Result</span><(), error::Unspecified>, |
| { |
| <span class="kw">let </span><span class="kw-2">mut </span>key_bytes = [<span class="number">0</span>; digest::MAX_OUTPUT_LEN]; |
| <span class="kw">let </span>key_bytes = <span class="kw-2">&mut </span>key_bytes[..algorithm.<span class="number">0</span>.output_len]; |
| fill(key_bytes)<span class="question-mark">?</span>; |
| <span class="prelude-val">Ok</span>(<span class="self">Self</span>::new(algorithm, key_bytes)) |
| } |
| |
| <span class="doccomment">/// Construct an HMAC signing key using the given digest algorithm and key |
| /// value. |
| /// |
| /// `key_value` should be a value generated using a secure random number |
| /// generator (e.g. the `key_value` output by |
| /// `SealingKey::generate_serializable()`) or derived from a random key by |
| /// a key derivation function (e.g. `ring::hkdf`). In particular, |
| /// `key_value` shouldn't be a password. |
| /// |
| /// As specified in RFC 2104, if `key_value` is shorter than the digest |
| /// algorithm's block length (as returned by `digest::Algorithm::block_len`, |
| /// not the digest length returned by `digest::Algorithm::output_len`) then |
| /// it will be padded with zeros. Similarly, if it is longer than the block |
| /// length then it will be compressed using the digest algorithm. |
| /// |
| /// You should not use keys larger than the `digest_alg.block_len` because |
| /// the truncation described above reduces their strength to only |
| /// `digest_alg.output_len * 8` bits. Support for such keys is likely to be |
| /// removed in a future version of *ring*. |
| </span><span class="kw">pub fn </span>new(algorithm: Algorithm, key_value: <span class="kw-2">&</span>[u8]) -> <span class="self">Self </span>{ |
| <span class="kw">let </span>digest_alg = algorithm.<span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>key = <span class="self">Self </span>{ |
| inner: digest::BlockContext::new(digest_alg), |
| outer: digest::BlockContext::new(digest_alg), |
| }; |
| |
| <span class="kw">let </span>key_hash; |
| <span class="kw">let </span>key_value = <span class="kw">if </span>key_value.len() <= digest_alg.block_len { |
| key_value |
| } <span class="kw">else </span>{ |
| key_hash = digest::digest(digest_alg, key_value); |
| key_hash.as_ref() |
| }; |
| |
| <span class="kw">const </span>IPAD: u8 = <span class="number">0x36</span>; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>padded_key = [IPAD; digest::MAX_BLOCK_LEN]; |
| <span class="kw">let </span>padded_key = <span class="kw-2">&mut </span>padded_key[..digest_alg.block_len]; |
| |
| <span class="comment">// If the key is shorter than one block then we're supposed to act like |
| // it is padded with zero bytes up to the block length. `x ^ 0 == x` so |
| // we can just leave the trailing bytes of `padded_key` untouched. |
| </span><span class="kw">for </span>(padded_key, key_value) <span class="kw">in </span>padded_key.iter_mut().zip(key_value.iter()) { |
| <span class="kw-2">*</span>padded_key ^= <span class="kw-2">*</span>key_value; |
| } |
| key.inner.update(<span class="kw-2">&</span>padded_key); |
| |
| <span class="kw">const </span>OPAD: u8 = <span class="number">0x5C</span>; |
| |
| <span class="comment">// Remove the `IPAD` masking, leaving the unmasked padded key, then |
| // mask with `OPAD`, all in one step. |
| </span><span class="kw">for </span>b <span class="kw">in </span>padded_key.iter_mut() { |
| <span class="kw-2">*</span>b ^= IPAD ^ OPAD; |
| } |
| key.outer.update(<span class="kw-2">&</span>padded_key); |
| |
| key |
| } |
| |
| <span class="doccomment">/// The digest algorithm for the key. |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>algorithm(<span class="kw-2">&</span><span class="self">self</span>) -> Algorithm { |
| Algorithm(<span class="self">self</span>.inner.algorithm) |
| } |
| } |
| |
| <span class="kw">impl </span>hkdf::KeyType <span class="kw">for </span>Algorithm { |
| <span class="kw">fn </span>len(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="self">self</span>.digest_algorithm().output_len |
| } |
| } |
| |
| <span class="kw">impl </span>From<hkdf::Okm<<span class="lifetime">'_</span>, Algorithm>> <span class="kw">for </span>Key { |
| <span class="kw">fn </span>from(okm: hkdf::Okm<Algorithm>) -> <span class="self">Self </span>{ |
| Key::construct(<span class="kw-2">*</span>okm.len(), |buf| okm.fill(buf)).unwrap() |
| } |
| } |
| |
| <span class="doccomment">/// A context for multi-step (Init-Update-Finish) HMAC signing. |
| /// |
| /// Use `sign` for single-step HMAC signing. |
| </span><span class="attribute">#[derive(Clone)] |
| </span><span class="kw">pub struct </span>Context { |
| inner: digest::Context, |
| outer: digest::BlockContext, |
| } |
| |
| <span class="doccomment">/// `hmac::SigningContext` was renamed to `hmac::Context`. |
| </span><span class="attribute">#[deprecated(note = <span class="string">"Renamed to `hmac::Context`."</span>)] |
| </span><span class="kw">pub type </span>SigningContext = Context; |
| |
| <span class="kw">impl </span>core::fmt::Debug <span class="kw">for </span>Context { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, f: <span class="kw-2">&mut </span>core::fmt::Formatter) -> <span class="prelude-ty">Result</span><(), core::fmt::Error> { |
| f.debug_struct(<span class="string">"Context"</span>) |
| .field(<span class="string">"algorithm"</span>, <span class="self">self</span>.inner.algorithm()) |
| .finish() |
| } |
| } |
| |
| <span class="kw">impl </span>Context { |
| <span class="doccomment">/// Constructs a new HMAC signing context using the given digest algorithm |
| /// and key. |
| </span><span class="kw">pub fn </span>with_key(signing_key: <span class="kw-2">&</span>Key) -> <span class="self">Self </span>{ |
| <span class="self">Self </span>{ |
| inner: digest::Context::clone_from(<span class="kw-2">&</span>signing_key.inner), |
| outer: signing_key.outer.clone(), |
| } |
| } |
| |
| <span class="doccomment">/// Updates the HMAC with all the data in `data`. `update` may be called |
| /// zero or more times until `finish` is called. |
| </span><span class="kw">pub fn </span>update(<span class="kw-2">&mut </span><span class="self">self</span>, data: <span class="kw-2">&</span>[u8]) { |
| <span class="self">self</span>.inner.update(data); |
| } |
| |
| <span class="doccomment">/// Finalizes the HMAC calculation and returns the HMAC value. `sign` |
| /// consumes the context so it cannot be (mis-)used after `sign` has been |
| /// called. |
| /// |
| /// It is generally not safe to implement HMAC verification by comparing |
| /// the return value of `sign` to a tag. Use `verify` for verification |
| /// instead. |
| </span><span class="kw">pub fn </span>sign(<span class="self">self</span>) -> Tag { |
| <span class="kw">let </span>algorithm = <span class="self">self</span>.inner.algorithm(); |
| <span class="kw">let </span><span class="kw-2">mut </span>pending = [<span class="number">0u8</span>; digest::MAX_BLOCK_LEN]; |
| <span class="kw">let </span>pending = <span class="kw-2">&mut </span>pending[..algorithm.block_len]; |
| <span class="kw">let </span>num_pending = algorithm.output_len; |
| pending[..num_pending].copy_from_slice(<span class="self">self</span>.inner.finish().as_ref()); |
| Tag(<span class="self">self</span>.outer.finish(pending, num_pending)) |
| } |
| } |
| |
| <span class="doccomment">/// Calculates the HMAC of `data` using the key `key` in one step. |
| /// |
| /// Use `Context` to calculate HMACs where the input is in multiple parts. |
| /// |
| /// It is generally not safe to implement HMAC verification by comparing the |
| /// return value of `sign` to a tag. Use `verify` for verification instead. |
| </span><span class="kw">pub fn </span>sign(key: <span class="kw-2">&</span>Key, data: <span class="kw-2">&</span>[u8]) -> Tag { |
| <span class="kw">let </span><span class="kw-2">mut </span>ctx = Context::with_key(key); |
| ctx.update(data); |
| ctx.sign() |
| } |
| |
| <span class="doccomment">/// Calculates the HMAC of `data` using the signing key `key`, and verifies |
| /// whether the resultant value equals `tag`, in one step. |
| /// |
| /// This is logically equivalent to, but more efficient than, constructing a |
| /// `Key` with the same value as `key` and then using `verify`. |
| /// |
| /// The verification will be done in constant time to prevent timing attacks. |
| </span><span class="kw">pub fn </span>verify(key: <span class="kw-2">&</span>Key, data: <span class="kw-2">&</span>[u8], tag: <span class="kw-2">&</span>[u8]) -> <span class="prelude-ty">Result</span><(), error::Unspecified> { |
| constant_time::verify_slices_are_equal(sign(key, data).as_ref(), tag) |
| } |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">use crate</span>::{hmac, rand}; |
| |
| <span class="comment">// Make sure that `Key::generate` and `verify_with_own_key` aren't |
| // completely wacky. |
| </span><span class="attribute">#[test] |
| </span><span class="kw">pub fn </span>hmac_signing_key_coverage() { |
| <span class="kw">let </span>rng = rand::SystemRandom::new(); |
| |
| <span class="kw">const </span>HELLO_WORLD_GOOD: <span class="kw-2">&</span>[u8] = <span class="string">b"hello, world"</span>; |
| <span class="kw">const </span>HELLO_WORLD_BAD: <span class="kw-2">&</span>[u8] = <span class="string">b"hello, worle"</span>; |
| |
| <span class="kw">for </span>algorithm <span class="kw">in </span><span class="kw-2">&</span>[ |
| hmac::HMAC_SHA1_FOR_LEGACY_USE_ONLY, |
| hmac::HMAC_SHA256, |
| hmac::HMAC_SHA384, |
| hmac::HMAC_SHA512, |
| ] { |
| <span class="kw">let </span>key = hmac::Key::generate(<span class="kw-2">*</span>algorithm, <span class="kw-2">&</span>rng).unwrap(); |
| <span class="kw">let </span>tag = hmac::sign(<span class="kw-2">&</span>key, HELLO_WORLD_GOOD); |
| <span class="macro">assert!</span>(hmac::verify(<span class="kw-2">&</span>key, HELLO_WORLD_GOOD, tag.as_ref()).is_ok()); |
| <span class="macro">assert!</span>(hmac::verify(<span class="kw-2">&</span>key, HELLO_WORLD_BAD, tag.as_ref()).is_err()) |
| } |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="ring" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
