oqs/
sig.rs

1//! Signature API
2//!
3//! See [`Sig`] for the main functionality and [`Algorithm`]
4//! for the list of supported algorithms.
5use alloc::vec::Vec;
6
7use core::ptr::{null, NonNull};
8use core::str::FromStr;
9
10#[cfg(not(feature = "std"))]
11use cstr_core::CStr;
12#[cfg(feature = "std")]
13use std::ffi::CStr;
14
15use crate::ffi::sig as ffi;
16use crate::newtype_buffer;
17use crate::*;
18
19#[cfg(feature = "serde")]
20use serde::{Deserialize, Serialize};
21
22newtype_buffer!(PublicKey, PublicKeyRef);
23newtype_buffer!(SecretKey, SecretKeyRef);
24newtype_buffer!(Signature, SignatureRef);
25
26/// Message type
27pub type Message = [u8];
28/// Context string type
29pub type CtxStr = [u8];
30
31macro_rules! implement_sigs {
32    { $(($feat: literal) $sig: ident: $oqs_id: ident),* $(,)? } => (
33        /// Supported algorithms by liboqs
34        ///
35        /// They may not all be enabled
36        ///
37        /// Optional support for `serde` if that feature is enabled.
38        #[derive(Clone, Copy, Debug, Eq, PartialEq, Hash)]
39        #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
40        #[allow(missing_docs)]
41        pub enum Algorithm {
42            $(
43                $sig,
44            )*
45        }
46
47        fn algorithm_to_id(algorithm: Algorithm) -> *const libc::c_char {
48            let id: &[u8] = match algorithm {
49                $(
50                    Algorithm::$sig => &ffi::$oqs_id[..],
51                )*
52            };
53            id as *const _ as *const libc::c_char
54        }
55
56        impl FromStr for Algorithm {
57            type Err = crate::Error;
58
59            fn from_str(s: &str) -> Result<Self> {
60                $(
61                    if s == Algorithm::$sig.name() {
62                        return Ok(Algorithm::$sig);
63                    }
64                )*
65                Err(crate::Error::AlgorithmParsingError)
66            }
67        }
68
69        $(
70            #[cfg(test)]
71            #[allow(non_snake_case)]
72            mod $sig {
73                use super::*;
74
75                #[test]
76                #[cfg(feature = $feat)]
77                fn test_signing() -> Result<()> {
78                    crate::init();
79                    let message = [0u8; 100];
80                    let sig = Sig::new(Algorithm::$sig)?;
81                    let (pk, sk) = sig.keypair()?;
82                    let signature = sig.sign(&message, &sk)?;
83                    sig.verify(&message, &signature, &pk)
84                }
85
86                #[test]
87                #[cfg(feature = $feat)]
88                fn test_signing_with_empty_context_string() -> Result<()> {
89                    crate::init();
90                    let message = [0u8; 100];
91                    let ctx_str: [u8; 0] = [];
92                    let sig = Sig::new(Algorithm::$sig)?;
93                    let (pk, sk) = sig.keypair()?;
94                    let signature = sig.sign_with_ctx_str(&message, &ctx_str, &sk)?;
95                    sig.verify_with_ctx_str(&message, &signature, &ctx_str, &pk)
96                }
97
98                #[test]
99                #[cfg(feature = $feat)]
100                fn test_signing_with_nonempty_context_string() -> Result<()> {
101                    crate::init();
102                    let message = [0u8; 100];
103                    let ctx_str = [0u8; 100];
104                    let sig = Sig::new(Algorithm::$sig)?;
105                    let (pk, sk) = sig.keypair()?;
106                    if sig.has_ctx_str_support() {
107                        let signature = sig.sign_with_ctx_str(&message, &ctx_str, &sk)?;
108                        sig.verify_with_ctx_str(&message, &signature, &ctx_str, &pk)
109                    } else {
110                        let sig_result = sig.sign_with_ctx_str(&message, &ctx_str, &sk);
111                        // Expect a generic error
112                        let sig_result: Result<()> = match sig_result {
113                            Err(Error::Error) => Ok(()),
114                            Ok(_) => Err(Error::Error),
115                            Err(e) => Err(e)
116                        };
117                        if sig_result.is_ok() {
118                            // get a valid signature with which to test verify
119                            let signature = sig.sign(&message, &sk)?;
120                            // Expect a generic error
121                            match sig.verify_with_ctx_str(&message, &signature, &ctx_str, &pk) {
122                                Err(Error::Error) => Ok(()),
123                                Ok(_) => Err(Error::Error),
124                                Err(e) => Err(e)
125
126                            }
127                        } else {
128                            sig_result
129                        }
130                    }
131                }
132
133                #[test]
134                fn test_enabled() {
135                    crate::init();
136                    if cfg!(feature = $feat) {
137                        assert!(Algorithm::$sig.is_enabled());
138                    } else {
139                        assert!(!Algorithm::$sig.is_enabled())
140                    }
141                }
142
143                #[test]
144                fn test_name() {
145                    let algo = Algorithm::$sig;
146                    // Just make sure the name impl does not panic or crash.
147                    let name = algo.name();
148
149                    #[cfg(feature = "std")]
150                    assert_eq!(name, algo.to_string());
151
152                    // ... And actually contains something.
153                    assert!(!name.is_empty());
154                }
155
156                #[test]
157                fn test_get_algorithm_back() {
158                    let algorithm = Algorithm::$sig;
159                    if algorithm.is_enabled() {
160                        let sig = Sig::new(algorithm).unwrap();
161                        assert_eq!(algorithm, sig.algorithm());
162                    }
163                }
164
165                #[test]
166                fn test_version() {
167                    if let Ok(sig) = Sig::new(Algorithm::$sig) {
168                        // Just make sure the version can be called without panic
169                        let version = sig.version();
170                        // ... And actually contains something.
171                        assert!(!version.is_empty());
172                    }
173                }
174
175                #[test]
176                fn test_from_str() {
177                    let algorithm = Algorithm::$sig;
178                    let name = algorithm.name();
179                    let parsed = Algorithm::from_str(name).unwrap();
180                    assert_eq!(algorithm, parsed);}
181            }
182        )*
183    )
184}
185
186implement_sigs! {
187    ("cross") CrossRsdp128Balanced: OQS_SIG_alg_cross_rsdp_128_balanced,
188    ("cross") CrossRsdp128Fast: OQS_SIG_alg_cross_rsdp_128_fast,
189    ("cross") CrossRsdp128Small: OQS_SIG_alg_cross_rsdp_128_small,
190    ("cross") CrossRsdp192Balanced: OQS_SIG_alg_cross_rsdp_192_balanced,
191    ("cross") CrossRsdp192Fast: OQS_SIG_alg_cross_rsdp_192_fast,
192    ("cross") CrossRsdp192Small: OQS_SIG_alg_cross_rsdp_192_small,
193    ("cross") CrossRsdp256Balanced: OQS_SIG_alg_cross_rsdp_256_balanced,
194    ("cross") CrossRsdp256Fast: OQS_SIG_alg_cross_rsdp_256_fast,
195    ("cross") CrossRsdp256Small: OQS_SIG_alg_cross_rsdp_256_small,
196    ("cross") CrossRsdpg128Balanced: OQS_SIG_alg_cross_rsdpg_128_balanced,
197    ("cross") CrossRsdpg128Fast: OQS_SIG_alg_cross_rsdpg_128_fast,
198    ("cross") CrossRsdpg128Small: OQS_SIG_alg_cross_rsdpg_128_small,
199    ("cross") CrossRsdpg192Balanced: OQS_SIG_alg_cross_rsdpg_192_balanced,
200    ("cross") CrossRsdpg192Fast: OQS_SIG_alg_cross_rsdpg_192_fast,
201    ("cross") CrossRsdpg192Small: OQS_SIG_alg_cross_rsdpg_192_small,
202    ("cross") CrossRsdpg256Balanced: OQS_SIG_alg_cross_rsdpg_256_balanced,
203    ("cross") CrossRsdpg256Fast: OQS_SIG_alg_cross_rsdpg_256_fast,
204    ("cross") CrossRsdpg256Small: OQS_SIG_alg_cross_rsdpg_256_small,
205    ("falcon") Falcon512: OQS_SIG_alg_falcon_512,
206    ("falcon") Falcon1024: OQS_SIG_alg_falcon_1024,
207    ("mayo") Mayo1: OQS_SIG_alg_mayo_1,
208    ("mayo") Mayo2: OQS_SIG_alg_mayo_2,
209    ("mayo") Mayo3: OQS_SIG_alg_mayo_3,
210    ("mayo") Mayo5: OQS_SIG_alg_mayo_5,
211    ("ml_dsa") MlDsa44: OQS_SIG_alg_ml_dsa_44,
212    ("ml_dsa") MlDsa65: OQS_SIG_alg_ml_dsa_65,
213    ("ml_dsa") MlDsa87: OQS_SIG_alg_ml_dsa_87,
214    ("sphincs") SphincsSha2128fSimple: OQS_SIG_alg_sphincs_sha2_128f_simple,
215    ("sphincs") SphincsSha2128sSimple: OQS_SIG_alg_sphincs_sha2_128s_simple,
216    ("sphincs") SphincsSha2192fSimple: OQS_SIG_alg_sphincs_sha2_192f_simple,
217    ("sphincs") SphincsSha2192sSimple: OQS_SIG_alg_sphincs_sha2_192s_simple,
218    ("sphincs") SphincsSha2256fSimple: OQS_SIG_alg_sphincs_sha2_256f_simple,
219    ("sphincs") SphincsSha2256sSimple: OQS_SIG_alg_sphincs_sha2_256s_simple,
220    ("sphincs") SphincsShake128fSimple: OQS_SIG_alg_sphincs_shake_128f_simple,
221    ("sphincs") SphincsShake128sSimple: OQS_SIG_alg_sphincs_shake_128s_simple,
222    ("sphincs") SphincsShake192fSimple: OQS_SIG_alg_sphincs_shake_192f_simple,
223    ("sphincs") SphincsShake192sSimple: OQS_SIG_alg_sphincs_shake_192s_simple,
224    ("sphincs") SphincsShake256fSimple: OQS_SIG_alg_sphincs_shake_256f_simple,
225    ("sphincs") SphincsShake256sSimple: OQS_SIG_alg_sphincs_shake_256s_simple,
226    ("uov") UovOvIs: OQS_SIG_alg_uov_ov_Is,
227    ("uov") UovOvIp: OQS_SIG_alg_uov_ov_Ip,
228    ("uov") UovOvIII: OQS_SIG_alg_uov_ov_III,
229    ("uov") UovOvV: OQS_SIG_alg_uov_ov_V,
230    ("uov") UovOvIsPkc: OQS_SIG_alg_uov_ov_Is_pkc,
231    ("uov") UovOvIpPkc: OQS_SIG_alg_uov_ov_Ip_pkc,
232    ("uov") UovOvIIIPkc: OQS_SIG_alg_uov_ov_III_pkc,
233    ("uov") UovOvVPkc: OQS_SIG_alg_uov_ov_V_pkc,
234    ("uov") UovOvIsPkcSkc: OQS_SIG_alg_uov_ov_Is_pkc_skc,
235    ("uov") UovOvIpPkcSkc: OQS_SIG_alg_uov_ov_Ip_pkc_skc,
236    ("uov") UovOvIIIPkcSkc: OQS_SIG_alg_uov_ov_III_pkc_skc,
237    ("uov") UovOvVPkcSkc: OQS_SIG_alg_uov_ov_V_pkc_skc,
238}
239
240impl Algorithm {
241    /// Returns true if this algorithm is enabled in the linked version
242    /// of liboqs
243    pub fn is_enabled(self) -> bool {
244        unsafe { ffi::OQS_SIG_alg_is_enabled(algorithm_to_id(self)) == 1 }
245    }
246
247    /// Provides a pointer to the id of the algorithm
248    ///
249    /// For use with the FFI api methods
250    pub fn to_id(self) -> *const libc::c_char {
251        algorithm_to_id(self)
252    }
253
254    /// Returns the algorithm's name as a static Rust string.
255    ///
256    /// This is the same as the `to_id`, but as a safe Rust string.
257    pub fn name(&self) -> &'static str {
258        // SAFETY: The id from ffi must be a proper null terminated C string
259        let id = unsafe { CStr::from_ptr(self.to_id()) };
260        id.to_str().expect("OQS algorithm names must be UTF-8")
261    }
262}
263
264/// Signature scheme
265///
266/// # Example
267/// ```rust
268/// # if !cfg!(feature = "ml_dsa") { return; }
269/// use oqs;
270/// oqs::init();
271/// let scheme = oqs::sig::Sig::new(oqs::sig::Algorithm::MlDsa44).unwrap();
272/// let message = [0u8; 100];
273/// let (pk, sk) = scheme.keypair().unwrap();
274/// let signature = scheme.sign(&message, &sk).unwrap();
275/// assert!(scheme.verify(&message, &signature, &pk).is_ok());
276/// ```
277pub struct Sig {
278    algorithm: Algorithm,
279    sig: NonNull<ffi::OQS_SIG>,
280}
281
282unsafe impl Sync for Sig {}
283unsafe impl Send for Sig {}
284
285impl Drop for Sig {
286    fn drop(&mut self) {
287        unsafe { ffi::OQS_SIG_free(self.sig.as_ptr()) };
288    }
289}
290
291#[cfg(feature = "std")]
292impl std::fmt::Display for Algorithm {
293    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
294        self.name().fmt(f)
295    }
296}
297
298impl core::convert::TryFrom<Algorithm> for Sig {
299    type Error = crate::Error;
300    fn try_from(alg: Algorithm) -> Result<Sig> {
301        Sig::new(alg)
302    }
303}
304
305impl Sig {
306    /// Construct a new algorithm
307    ///
308    /// May fail if the algorithm is not available
309    pub fn new(algorithm: Algorithm) -> Result<Self> {
310        let sig = unsafe { ffi::OQS_SIG_new(algorithm_to_id(algorithm)) };
311        NonNull::new(sig).map_or_else(
312            || Err(Error::AlgorithmDisabled),
313            |sig| Ok(Self { algorithm, sig }),
314        )
315    }
316
317    /// Get the algorithm used by this `Sig`
318    pub fn algorithm(&self) -> Algorithm {
319        self.algorithm
320    }
321
322    /// Get the version of the implementation
323    pub fn version(&self) -> &'static str {
324        let sig = unsafe { self.sig.as_ref() };
325        // SAFETY: The alg_version from ffi must be a proper null terminated C string
326        let cstr = unsafe { CStr::from_ptr(sig.alg_version) };
327        cstr.to_str()
328            .expect("Algorithm version strings must be UTF-8")
329    }
330
331    /// Obtain the claimed nist level
332    pub fn claimed_nist_level(&self) -> u8 {
333        let sig = unsafe { self.sig.as_ref() };
334        sig.claimed_nist_level
335    }
336
337    /// Is this algorithm EUF-CMA?
338    pub fn is_euf_cma(&self) -> bool {
339        let sig = unsafe { self.sig.as_ref() };
340        sig.euf_cma
341    }
342
343    /// Does this algorithm support signing with a context string?
344    pub fn has_ctx_str_support(&self) -> bool {
345        let sig = unsafe { self.sig.as_ref() };
346        sig.sig_with_ctx_support
347    }
348
349    /// Length of the public key
350    pub fn length_public_key(&self) -> usize {
351        let sig = unsafe { self.sig.as_ref() };
352        sig.length_public_key
353    }
354
355    /// Length of the secret key
356    pub fn length_secret_key(&self) -> usize {
357        let sig = unsafe { self.sig.as_ref() };
358        sig.length_secret_key
359    }
360
361    /// Maximum length of a signature
362    pub fn length_signature(&self) -> usize {
363        let sig = unsafe { self.sig.as_ref() };
364        sig.length_signature
365    }
366
367    /// Construct a secret key object from bytes
368    pub fn secret_key_from_bytes<'a>(&self, buf: &'a [u8]) -> Option<SecretKeyRef<'a>> {
369        if buf.len() != self.length_secret_key() {
370            None
371        } else {
372            Some(SecretKeyRef::new(buf))
373        }
374    }
375
376    /// Construct a public key object from bytes
377    pub fn public_key_from_bytes<'a>(&self, buf: &'a [u8]) -> Option<PublicKeyRef<'a>> {
378        if buf.len() != self.length_public_key() {
379            None
380        } else {
381            Some(PublicKeyRef::new(buf))
382        }
383    }
384
385    /// Construct a signature object from bytes
386    pub fn signature_from_bytes<'a>(&self, buf: &'a [u8]) -> Option<SignatureRef<'a>> {
387        if buf.len() > self.length_signature() {
388            None
389        } else {
390            Some(SignatureRef::new(buf))
391        }
392    }
393
394    /// Generate a new keypair
395    pub fn keypair(&self) -> Result<(PublicKey, SecretKey)> {
396        let sig = unsafe { self.sig.as_ref() };
397        let func = sig.keypair.unwrap();
398        let mut pk = PublicKey {
399            bytes: Vec::with_capacity(sig.length_public_key),
400        };
401        let mut sk = SecretKey {
402            bytes: Vec::with_capacity(sig.length_secret_key),
403        };
404        let status = unsafe { func(pk.bytes.as_mut_ptr(), sk.bytes.as_mut_ptr()) };
405        // update the lengths of the vecs
406        unsafe {
407            pk.bytes.set_len(sig.length_public_key);
408            sk.bytes.set_len(sig.length_secret_key);
409        }
410        status_to_result(status)?;
411        Ok((pk, sk))
412    }
413
414    /// Sign a message
415    pub fn sign<'a, S: Into<SecretKeyRef<'a>>>(
416        &self,
417        message: &Message,
418        sk: S,
419    ) -> Result<Signature> {
420        let sk = sk.into();
421        let sig = unsafe { self.sig.as_ref() };
422        let func = sig.sign.unwrap();
423        let mut sig = Signature {
424            bytes: Vec::with_capacity(sig.length_signature),
425        };
426        let mut sig_len = 0;
427        let status = unsafe {
428            func(
429                sig.bytes.as_mut_ptr(),
430                &mut sig_len,
431                message.as_ptr(),
432                message.len(),
433                sk.bytes.as_ptr(),
434            )
435        };
436        status_to_result(status)?;
437        // This is safe to do as it's initialised now.
438        unsafe {
439            sig.bytes.set_len(sig_len);
440        }
441        Ok(sig)
442    }
443
444    /// Sign a message with a context string
445    pub fn sign_with_ctx_str<'a, S: Into<SecretKeyRef<'a>>>(
446        &self,
447        message: &Message,
448        ctx_str: &CtxStr,
449        sk: S,
450    ) -> Result<Signature> {
451        let sk = sk.into();
452        let sig = unsafe { self.sig.as_ref() };
453        let func = sig.sign_with_ctx_str.unwrap();
454        let mut sig = Signature {
455            bytes: Vec::with_capacity(sig.length_signature),
456        };
457        let mut sig_len = 0;
458        // For algorithms without context string support, liboqs
459        // expects the context to be NULL. Converting an empty
460        // slice to a pointer doesn't actually do this.
461        let ctx_str_ptr = if !ctx_str.is_empty() {
462            ctx_str.as_ptr()
463        } else {
464            null()
465        };
466        let status = unsafe {
467            func(
468                sig.bytes.as_mut_ptr(),
469                &mut sig_len,
470                message.as_ptr(),
471                message.len(),
472                ctx_str_ptr,
473                ctx_str.len(),
474                sk.bytes.as_ptr(),
475            )
476        };
477        status_to_result(status)?;
478        // This is safe to do as it's initialised now.
479        unsafe {
480            sig.bytes.set_len(sig_len);
481        }
482        Ok(sig)
483    }
484
485    /// Verify a message
486    pub fn verify<'a, 'b>(
487        &self,
488        message: &Message,
489        signature: impl Into<SignatureRef<'a>>,
490        pk: impl Into<PublicKeyRef<'b>>,
491    ) -> Result<()> {
492        let signature = signature.into();
493        let pk = pk.into();
494        if signature.bytes.len() > self.length_signature()
495            || pk.bytes.len() != self.length_public_key()
496        {
497            return Err(Error::InvalidLength);
498        }
499        let sig = unsafe { self.sig.as_ref() };
500        let func = sig.verify.unwrap();
501        let status = unsafe {
502            func(
503                message.as_ptr(),
504                message.len(),
505                signature.bytes.as_ptr(),
506                signature.len(),
507                pk.bytes.as_ptr(),
508            )
509        };
510        status_to_result(status)
511    }
512
513    /// Verify a message with a context string
514    pub fn verify_with_ctx_str<'a, 'b>(
515        &self,
516        message: &Message,
517        signature: impl Into<SignatureRef<'a>>,
518        ctx_str: &CtxStr,
519        pk: impl Into<PublicKeyRef<'b>>,
520    ) -> Result<()> {
521        let signature = signature.into();
522        let pk = pk.into();
523        if signature.bytes.len() > self.length_signature()
524            || pk.bytes.len() != self.length_public_key()
525        {
526            return Err(Error::InvalidLength);
527        }
528        let sig = unsafe { self.sig.as_ref() };
529        let func = sig.verify_with_ctx_str.unwrap();
530        // For algorithms without context string support, liboqs
531        // expects the context to be NULL. Converting an empty
532        // slice to a pointer doesn't actually do this.
533        let ctx_str_ptr = if !ctx_str.is_empty() {
534            ctx_str.as_ptr()
535        } else {
536            null()
537        };
538        let status = unsafe {
539            func(
540                message.as_ptr(),
541                message.len(),
542                signature.bytes.as_ptr(),
543                signature.len(),
544                ctx_str_ptr,
545                ctx_str.len(),
546                pk.bytes.as_ptr(),
547            )
548        };
549        status_to_result(status)
550    }
551}
oqs/sig.rs

oqs/
sig.rs
