Struct openssl::rsa::Padding

pub struct Padding(_);

Type of encryption padding to use.

Random length padding is primarily used to prevent attackers from predicting or knowing the exact length of a plaintext message that can possibly lead to breaking encryption.

Implementations

impl Padding

pub const NONE: Padding = _

pub const PKCS1: Padding = _

pub const PKCS1_OAEP: Padding = _

pub const PKCS1_PSS: Padding = _

pub fn from_raw(value: c_int) -> Padding

Creates a Padding from an integer representation.

Examples found in repository

src/pkey_ctx.rs (line 350)

    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        let mut pad = 0;
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.as_ptr(), &mut pad))?;
        }

        Ok(Padding::from_raw(pad))
    }

src/encrypt.rs (line 106)

    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        unsafe {
            let mut pad = 0;
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.pctx, &mut pad))
                .map(|_| Padding::from_raw(pad))
        }
    }

    /// Sets the RSA padding mode.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_padding`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_padding`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_PKEY_CTX_set_rsa_padding.html
    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.pctx,
                padding.as_raw(),
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA MGF1 algorithm.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_mgf1_md`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_mgf1_md`]: https://www.openssl.org/docs/manmaster/man7/RSA-PSS.html
    pub fn set_rsa_mgf1_md(&mut self, md: MessageDigest) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_mgf1_md(
                self.pctx,
                md.as_ptr() as *mut _,
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA OAEP algorithm.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_oaep_md`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_oaep_md`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_CTX_set_rsa_oaep_md.html
    #[cfg(any(ossl102, libressl310))]
    pub fn set_rsa_oaep_md(&mut self, md: MessageDigest) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_oaep_md(
                self.pctx,
                md.as_ptr() as *mut _,
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA OAEP label.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set0_rsa_oaep_label`].
    ///
    /// [`EVP_PKEY_CTX_set0_rsa_oaep_label`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_CTX_set0_rsa_oaep_label.html
    #[cfg(any(ossl102, libressl310))]
    pub fn set_rsa_oaep_label(&mut self, label: &[u8]) -> Result<(), ErrorStack> {
        unsafe {
            let p = cvt_p(ffi::OPENSSL_malloc(label.len() as _))?;
            ptr::copy_nonoverlapping(label.as_ptr(), p as *mut u8, label.len());

            cvt(ffi::EVP_PKEY_CTX_set0_rsa_oaep_label(
                self.pctx,
                p as *mut c_void,
                label.len() as c_int,
            ))
            .map(|_| ())
            .map_err(|e| {
                ffi::OPENSSL_free(p);
                e
            })
        }
    }

    /// Performs public key encryption.
    ///
    /// In order to know the size needed for the output buffer, use [`encrypt_len`](Encrypter::encrypt_len).
    /// Note that the length of the output buffer can be greater of the length of the encoded data.
    /// ```
    /// # use openssl::{
    /// #   encrypt::Encrypter,
    /// #   pkey::PKey,
    /// #   rsa::{Rsa, Padding},
    /// # };
    /// #
    /// # let key = include_bytes!("../test/rsa.pem");
    /// # let private_key = Rsa::private_key_from_pem(key).unwrap();
    /// # let pkey = PKey::from_rsa(private_key).unwrap();
    /// # let input = b"hello world".to_vec();
    /// #
    /// let mut encrypter = Encrypter::new(&pkey).unwrap();
    /// encrypter.set_rsa_padding(Padding::PKCS1).unwrap();
    ///
    /// // Get the length of the output buffer
    /// let buffer_len = encrypter.encrypt_len(&input).unwrap();
    /// let mut encoded = vec![0u8; buffer_len];
    ///
    /// // Encode the data and get its length
    /// let encoded_len = encrypter.encrypt(&input, &mut encoded).unwrap();
    ///
    /// // Use only the part of the buffer with the encoded data
    /// let encoded = &encoded[..encoded_len];
    /// ```
    ///
    /// This corresponds to [`EVP_PKEY_encrypt`].
    ///
    /// [`EVP_PKEY_encrypt`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_encrypt.html
    pub fn encrypt(&self, from: &[u8], to: &mut [u8]) -> Result<usize, ErrorStack> {
        let mut written = to.len();
        unsafe {
            cvt(ffi::EVP_PKEY_encrypt(
                self.pctx,
                to.as_mut_ptr(),
                &mut written,
                from.as_ptr(),
                from.len(),
            ))?;
        }

        Ok(written)
    }

    /// Gets the size of the buffer needed to encrypt the input data.
    ///
    /// This corresponds to [`EVP_PKEY_encrypt`] called with a null pointer as output argument.
    ///
    /// [`EVP_PKEY_encrypt`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_encrypt.html
    pub fn encrypt_len(&self, from: &[u8]) -> Result<usize, ErrorStack> {
        let mut written = 0;
        unsafe {
            cvt(ffi::EVP_PKEY_encrypt(
                self.pctx,
                ptr::null_mut(),
                &mut written,
                from.as_ptr(),
                from.len(),
            ))?;
        }

        Ok(written)
    }
}

/// A type which decrypts data.
pub struct Decrypter<'a> {
    pctx: *mut ffi::EVP_PKEY_CTX,
    _p: PhantomData<&'a ()>,
}

unsafe impl<'a> Sync for Decrypter<'a> {}
unsafe impl<'a> Send for Decrypter<'a> {}

impl<'a> Drop for Decrypter<'a> {
    fn drop(&mut self) {
        unsafe {
            ffi::EVP_PKEY_CTX_free(self.pctx);
        }
    }
}

impl<'a> Decrypter<'a> {
    /// Creates a new `Decrypter`.
    ///
    /// OpenSSL documentation at [`EVP_PKEY_decrypt_init`].
    ///
    /// [`EVP_PKEY_decrypt_init`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_decrypt_init.html
    pub fn new<T>(pkey: &'a PKeyRef<T>) -> Result<Decrypter<'a>, ErrorStack>
    where
        T: HasPrivate,
    {
        unsafe {
            ffi::init();

            let pctx = cvt_p(ffi::EVP_PKEY_CTX_new(pkey.as_ptr(), ptr::null_mut()))?;
            let r = ffi::EVP_PKEY_decrypt_init(pctx);
            if r != 1 {
                ffi::EVP_PKEY_CTX_free(pctx);
                return Err(ErrorStack::get());
            }

            Ok(Decrypter {
                pctx,
                _p: PhantomData,
            })
        }
    }

    /// Returns the RSA padding mode in use.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to `EVP_PKEY_CTX_get_rsa_padding`.
    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        unsafe {
            let mut pad = 0;
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.pctx, &mut pad))
                .map(|_| Padding::from_raw(pad))
        }
    }

src/sign.rs (line 207)

    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        unsafe {
            let mut pad = 0;
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.pctx, &mut pad))
                .map(|_| Padding::from_raw(pad))
        }
    }

    /// Sets the RSA padding mode.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_padding`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_padding`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_PKEY_CTX_set_rsa_padding.html
    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.pctx,
                padding.as_raw(),
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA PSS salt length.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_pss_saltlen`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_pss_saltlen`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_PKEY_CTX_set_rsa_pss_saltlen.html
    pub fn set_rsa_pss_saltlen(&mut self, len: RsaPssSaltlen) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_pss_saltlen(
                self.pctx,
                len.as_raw(),
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA MGF1 algorithm.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_mgf1_md`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_mgf1_md`]: https://www.openssl.org/docs/manmaster/man7/RSA-PSS.html
    pub fn set_rsa_mgf1_md(&mut self, md: MessageDigest) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_mgf1_md(
                self.pctx,
                md.as_ptr() as *mut _,
            ))
            .map(|_| ())
        }
    }

    /// Feeds more data into the `Signer`.
    ///
    /// Please note that PureEdDSA (Ed25519 and Ed448 keys) do not support streaming.
    /// Use `sign_oneshot` instead.
    ///
    /// OpenSSL documentation at [`EVP_DigestUpdate`].
    ///
    /// [`EVP_DigestUpdate`]: https://www.openssl.org/docs/manmaster/man3/EVP_DigestInit.html
    pub fn update(&mut self, buf: &[u8]) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_DigestUpdate(
                self.md_ctx,
                buf.as_ptr() as *const _,
                buf.len(),
            ))
            .map(|_| ())
        }
    }

    /// Computes an upper bound on the signature length.
    ///
    /// The actual signature may be shorter than this value. Check the return value of
    /// `sign` to get the exact length.
    ///
    /// OpenSSL documentation at [`EVP_DigestSignFinal`].
    ///
    /// [`EVP_DigestSignFinal`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_DigestSignFinal.html
    pub fn len(&self) -> Result<usize, ErrorStack> {
        self.len_intern()
    }

    #[cfg(not(ossl111))]
    fn len_intern(&self) -> Result<usize, ErrorStack> {
        unsafe {
            let mut len = 0;
            cvt(ffi::EVP_DigestSignFinal(
                self.md_ctx,
                ptr::null_mut(),
                &mut len,
            ))?;
            Ok(len)
        }
    }

    #[cfg(ossl111)]
    fn len_intern(&self) -> Result<usize, ErrorStack> {
        unsafe {
            let mut len = 0;
            cvt(ffi::EVP_DigestSign(
                self.md_ctx,
                ptr::null_mut(),
                &mut len,
                ptr::null(),
                0,
            ))?;
            Ok(len)
        }
    }

    /// Writes the signature into the provided buffer, returning the number of bytes written.
    ///
    /// This method will fail if the buffer is not large enough for the signature. Use the `len`
    /// method to get an upper bound on the required size.
    ///
    /// OpenSSL documentation at [`EVP_DigestSignFinal`].
    ///
    /// [`EVP_DigestSignFinal`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_DigestSignFinal.html
    pub fn sign(&self, buf: &mut [u8]) -> Result<usize, ErrorStack> {
        unsafe {
            let mut len = buf.len();
            cvt(ffi::EVP_DigestSignFinal(
                self.md_ctx,
                buf.as_mut_ptr() as *mut _,
                &mut len,
            ))?;
            Ok(len)
        }
    }

    /// Returns the signature.
    ///
    /// This is a simple convenience wrapper over `len` and `sign`.
    pub fn sign_to_vec(&self) -> Result<Vec<u8>, ErrorStack> {
        let mut buf = vec![0; self.len()?];
        let len = self.sign(&mut buf)?;
        // The advertised length is not always equal to the real length for things like DSA
        buf.truncate(len);
        Ok(buf)
    }

    /// Signs the data in `data_buf` and writes the signature into the buffer `sig_buf`, returning the
    /// number of bytes written.
    ///
    /// For PureEdDSA (Ed25519 and Ed448 keys), this is the only way to sign data.
    ///
    /// This method will fail if the buffer is not large enough for the signature. Use the `len`
    /// method to get an upper bound on the required size.
    ///
    /// OpenSSL documentation at [`EVP_DigestSign`].
    ///
    /// [`EVP_DigestSign`]: https://www.openssl.org/docs/man1.1.1/man3/EVP_DigestSign.html
    #[cfg(ossl111)]
    pub fn sign_oneshot(
        &mut self,
        sig_buf: &mut [u8],
        data_buf: &[u8],
    ) -> Result<usize, ErrorStack> {
        unsafe {
            let mut sig_len = sig_buf.len();
            cvt(ffi::EVP_DigestSign(
                self.md_ctx,
                sig_buf.as_mut_ptr() as *mut _,
                &mut sig_len,
                data_buf.as_ptr() as *const _,
                data_buf.len(),
            ))?;
            Ok(sig_len)
        }
    }

    /// Returns the signature.
    ///
    /// This is a simple convenience wrapper over `len` and `sign_oneshot`.
    #[cfg(ossl111)]
    pub fn sign_oneshot_to_vec(&mut self, data_buf: &[u8]) -> Result<Vec<u8>, ErrorStack> {
        let mut sig_buf = vec![0; self.len()?];
        let len = self.sign_oneshot(&mut sig_buf, data_buf)?;
        // The advertised length is not always equal to the real length for things like DSA
        sig_buf.truncate(len);
        Ok(sig_buf)
    }
}

impl<'a> Write for Signer<'a> {
    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
        self.update(buf)?;
        Ok(buf.len())
    }

    fn flush(&mut self) -> io::Result<()> {
        Ok(())
    }
}

/// A type which can be used to verify the integrity and authenticity
/// of data given the signature.
pub struct Verifier<'a> {
    md_ctx: *mut ffi::EVP_MD_CTX,
    pctx: *mut ffi::EVP_PKEY_CTX,
    pkey_pd: PhantomData<&'a ()>,
}

unsafe impl<'a> Sync for Verifier<'a> {}
unsafe impl<'a> Send for Verifier<'a> {}

impl<'a> Drop for Verifier<'a> {
    fn drop(&mut self) {
        // pkey_ctx is owned by the md_ctx, so no need to explicitly free it.
        unsafe {
            EVP_MD_CTX_free(self.md_ctx);
        }
    }
}

/// A type which verifies cryptographic signatures of data.
impl<'a> Verifier<'a> {
    /// Creates a new `Verifier`.
    ///
    /// This cannot be used with Ed25519 or Ed448 keys. Please refer to
    /// [`Verifier::new_without_digest`].
    ///
    /// OpenSSL documentation at [`EVP_DigestVerifyInit`].
    ///
    /// [`EVP_DigestVerifyInit`]: https://www.openssl.org/docs/manmaster/man3/EVP_DigestVerifyInit.html
    pub fn new<T>(type_: MessageDigest, pkey: &'a PKeyRef<T>) -> Result<Verifier<'a>, ErrorStack>
    where
        T: HasPublic,
    {
        Verifier::new_intern(Some(type_), pkey)
    }

    /// Creates a new `Verifier` without a digest.
    ///
    /// This is the only way to create a `Verifier` for Ed25519 or Ed448 keys.
    ///
    /// OpenSSL documentation at [`EVP_DigestVerifyInit`].
    ///
    /// [`EVP_DigestVerifyInit`]: https://www.openssl.org/docs/manmaster/man3/EVP_DigestVerifyInit.html
    pub fn new_without_digest<T>(pkey: &'a PKeyRef<T>) -> Result<Verifier<'a>, ErrorStack>
    where
        T: HasPublic,
    {
        Verifier::new_intern(None, pkey)
    }

    fn new_intern<T>(
        type_: Option<MessageDigest>,
        pkey: &'a PKeyRef<T>,
    ) -> Result<Verifier<'a>, ErrorStack>
    where
        T: HasPublic,
    {
        unsafe {
            ffi::init();

            let ctx = cvt_p(EVP_MD_CTX_new())?;
            let mut pctx: *mut ffi::EVP_PKEY_CTX = ptr::null_mut();
            let r = ffi::EVP_DigestVerifyInit(
                ctx,
                &mut pctx,
                type_.map(|t| t.as_ptr()).unwrap_or(ptr::null()),
                ptr::null_mut(),
                pkey.as_ptr(),
            );
            if r != 1 {
                EVP_MD_CTX_free(ctx);
                return Err(ErrorStack::get());
            }

            assert!(!pctx.is_null());

            Ok(Verifier {
                md_ctx: ctx,
                pctx,
                pkey_pd: PhantomData,
            })
        }
    }

    /// Returns the RSA padding mode in use.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to `EVP_PKEY_CTX_get_rsa_padding`.
    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        unsafe {
            let mut pad = 0;
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.pctx, &mut pad))
                .map(|_| Padding::from_raw(pad))
        }
    }

pub fn as_raw(&self) -> c_int

Returns the integer representation of Padding.

Examples found in repository

src/pkey_ctx.rs (line 362)

    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.as_ptr(),
                padding.as_raw(),
            ))?;
        }

        Ok(())
    }

src/encrypt.rs (line 121)

    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.pctx,
                padding.as_raw(),
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA MGF1 algorithm.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_mgf1_md`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_mgf1_md`]: https://www.openssl.org/docs/manmaster/man7/RSA-PSS.html
    pub fn set_rsa_mgf1_md(&mut self, md: MessageDigest) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_mgf1_md(
                self.pctx,
                md.as_ptr() as *mut _,
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA OAEP algorithm.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_oaep_md`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_oaep_md`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_CTX_set_rsa_oaep_md.html
    #[cfg(any(ossl102, libressl310))]
    pub fn set_rsa_oaep_md(&mut self, md: MessageDigest) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_oaep_md(
                self.pctx,
                md.as_ptr() as *mut _,
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA OAEP label.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set0_rsa_oaep_label`].
    ///
    /// [`EVP_PKEY_CTX_set0_rsa_oaep_label`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_CTX_set0_rsa_oaep_label.html
    #[cfg(any(ossl102, libressl310))]
    pub fn set_rsa_oaep_label(&mut self, label: &[u8]) -> Result<(), ErrorStack> {
        unsafe {
            let p = cvt_p(ffi::OPENSSL_malloc(label.len() as _))?;
            ptr::copy_nonoverlapping(label.as_ptr(), p as *mut u8, label.len());

            cvt(ffi::EVP_PKEY_CTX_set0_rsa_oaep_label(
                self.pctx,
                p as *mut c_void,
                label.len() as c_int,
            ))
            .map(|_| ())
            .map_err(|e| {
                ffi::OPENSSL_free(p);
                e
            })
        }
    }

    /// Performs public key encryption.
    ///
    /// In order to know the size needed for the output buffer, use [`encrypt_len`](Encrypter::encrypt_len).
    /// Note that the length of the output buffer can be greater of the length of the encoded data.
    /// ```
    /// # use openssl::{
    /// #   encrypt::Encrypter,
    /// #   pkey::PKey,
    /// #   rsa::{Rsa, Padding},
    /// # };
    /// #
    /// # let key = include_bytes!("../test/rsa.pem");
    /// # let private_key = Rsa::private_key_from_pem(key).unwrap();
    /// # let pkey = PKey::from_rsa(private_key).unwrap();
    /// # let input = b"hello world".to_vec();
    /// #
    /// let mut encrypter = Encrypter::new(&pkey).unwrap();
    /// encrypter.set_rsa_padding(Padding::PKCS1).unwrap();
    ///
    /// // Get the length of the output buffer
    /// let buffer_len = encrypter.encrypt_len(&input).unwrap();
    /// let mut encoded = vec![0u8; buffer_len];
    ///
    /// // Encode the data and get its length
    /// let encoded_len = encrypter.encrypt(&input, &mut encoded).unwrap();
    ///
    /// // Use only the part of the buffer with the encoded data
    /// let encoded = &encoded[..encoded_len];
    /// ```
    ///
    /// This corresponds to [`EVP_PKEY_encrypt`].
    ///
    /// [`EVP_PKEY_encrypt`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_encrypt.html
    pub fn encrypt(&self, from: &[u8], to: &mut [u8]) -> Result<usize, ErrorStack> {
        let mut written = to.len();
        unsafe {
            cvt(ffi::EVP_PKEY_encrypt(
                self.pctx,
                to.as_mut_ptr(),
                &mut written,
                from.as_ptr(),
                from.len(),
            ))?;
        }

        Ok(written)
    }

    /// Gets the size of the buffer needed to encrypt the input data.
    ///
    /// This corresponds to [`EVP_PKEY_encrypt`] called with a null pointer as output argument.
    ///
    /// [`EVP_PKEY_encrypt`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_encrypt.html
    pub fn encrypt_len(&self, from: &[u8]) -> Result<usize, ErrorStack> {
        let mut written = 0;
        unsafe {
            cvt(ffi::EVP_PKEY_encrypt(
                self.pctx,
                ptr::null_mut(),
                &mut written,
                from.as_ptr(),
                from.len(),
            ))?;
        }

        Ok(written)
    }
}

/// A type which decrypts data.
pub struct Decrypter<'a> {
    pctx: *mut ffi::EVP_PKEY_CTX,
    _p: PhantomData<&'a ()>,
}

unsafe impl<'a> Sync for Decrypter<'a> {}
unsafe impl<'a> Send for Decrypter<'a> {}

impl<'a> Drop for Decrypter<'a> {
    fn drop(&mut self) {
        unsafe {
            ffi::EVP_PKEY_CTX_free(self.pctx);
        }
    }
}

impl<'a> Decrypter<'a> {
    /// Creates a new `Decrypter`.
    ///
    /// OpenSSL documentation at [`EVP_PKEY_decrypt_init`].
    ///
    /// [`EVP_PKEY_decrypt_init`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_decrypt_init.html
    pub fn new<T>(pkey: &'a PKeyRef<T>) -> Result<Decrypter<'a>, ErrorStack>
    where
        T: HasPrivate,
    {
        unsafe {
            ffi::init();

            let pctx = cvt_p(ffi::EVP_PKEY_CTX_new(pkey.as_ptr(), ptr::null_mut()))?;
            let r = ffi::EVP_PKEY_decrypt_init(pctx);
            if r != 1 {
                ffi::EVP_PKEY_CTX_free(pctx);
                return Err(ErrorStack::get());
            }

            Ok(Decrypter {
                pctx,
                _p: PhantomData,
            })
        }
    }

    /// Returns the RSA padding mode in use.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to `EVP_PKEY_CTX_get_rsa_padding`.
    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        unsafe {
            let mut pad = 0;
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.pctx, &mut pad))
                .map(|_| Padding::from_raw(pad))
        }
    }

    /// Sets the RSA padding mode.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_padding`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_padding`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_PKEY_CTX_set_rsa_padding.html
    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.pctx,
                padding.as_raw(),
            ))
            .map(|_| ())
        }
    }

src/sign.rs (line 222)

    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.pctx,
                padding.as_raw(),
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA PSS salt length.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_pss_saltlen`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_pss_saltlen`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_PKEY_CTX_set_rsa_pss_saltlen.html
    pub fn set_rsa_pss_saltlen(&mut self, len: RsaPssSaltlen) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_pss_saltlen(
                self.pctx,
                len.as_raw(),
            ))
            .map(|_| ())
        }
    }

    /// Sets the RSA MGF1 algorithm.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_mgf1_md`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_mgf1_md`]: https://www.openssl.org/docs/manmaster/man7/RSA-PSS.html
    pub fn set_rsa_mgf1_md(&mut self, md: MessageDigest) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_mgf1_md(
                self.pctx,
                md.as_ptr() as *mut _,
            ))
            .map(|_| ())
        }
    }

    /// Feeds more data into the `Signer`.
    ///
    /// Please note that PureEdDSA (Ed25519 and Ed448 keys) do not support streaming.
    /// Use `sign_oneshot` instead.
    ///
    /// OpenSSL documentation at [`EVP_DigestUpdate`].
    ///
    /// [`EVP_DigestUpdate`]: https://www.openssl.org/docs/manmaster/man3/EVP_DigestInit.html
    pub fn update(&mut self, buf: &[u8]) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_DigestUpdate(
                self.md_ctx,
                buf.as_ptr() as *const _,
                buf.len(),
            ))
            .map(|_| ())
        }
    }

    /// Computes an upper bound on the signature length.
    ///
    /// The actual signature may be shorter than this value. Check the return value of
    /// `sign` to get the exact length.
    ///
    /// OpenSSL documentation at [`EVP_DigestSignFinal`].
    ///
    /// [`EVP_DigestSignFinal`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_DigestSignFinal.html
    pub fn len(&self) -> Result<usize, ErrorStack> {
        self.len_intern()
    }

    #[cfg(not(ossl111))]
    fn len_intern(&self) -> Result<usize, ErrorStack> {
        unsafe {
            let mut len = 0;
            cvt(ffi::EVP_DigestSignFinal(
                self.md_ctx,
                ptr::null_mut(),
                &mut len,
            ))?;
            Ok(len)
        }
    }

    #[cfg(ossl111)]
    fn len_intern(&self) -> Result<usize, ErrorStack> {
        unsafe {
            let mut len = 0;
            cvt(ffi::EVP_DigestSign(
                self.md_ctx,
                ptr::null_mut(),
                &mut len,
                ptr::null(),
                0,
            ))?;
            Ok(len)
        }
    }

    /// Writes the signature into the provided buffer, returning the number of bytes written.
    ///
    /// This method will fail if the buffer is not large enough for the signature. Use the `len`
    /// method to get an upper bound on the required size.
    ///
    /// OpenSSL documentation at [`EVP_DigestSignFinal`].
    ///
    /// [`EVP_DigestSignFinal`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_DigestSignFinal.html
    pub fn sign(&self, buf: &mut [u8]) -> Result<usize, ErrorStack> {
        unsafe {
            let mut len = buf.len();
            cvt(ffi::EVP_DigestSignFinal(
                self.md_ctx,
                buf.as_mut_ptr() as *mut _,
                &mut len,
            ))?;
            Ok(len)
        }
    }

    /// Returns the signature.
    ///
    /// This is a simple convenience wrapper over `len` and `sign`.
    pub fn sign_to_vec(&self) -> Result<Vec<u8>, ErrorStack> {
        let mut buf = vec![0; self.len()?];
        let len = self.sign(&mut buf)?;
        // The advertised length is not always equal to the real length for things like DSA
        buf.truncate(len);
        Ok(buf)
    }

    /// Signs the data in `data_buf` and writes the signature into the buffer `sig_buf`, returning the
    /// number of bytes written.
    ///
    /// For PureEdDSA (Ed25519 and Ed448 keys), this is the only way to sign data.
    ///
    /// This method will fail if the buffer is not large enough for the signature. Use the `len`
    /// method to get an upper bound on the required size.
    ///
    /// OpenSSL documentation at [`EVP_DigestSign`].
    ///
    /// [`EVP_DigestSign`]: https://www.openssl.org/docs/man1.1.1/man3/EVP_DigestSign.html
    #[cfg(ossl111)]
    pub fn sign_oneshot(
        &mut self,
        sig_buf: &mut [u8],
        data_buf: &[u8],
    ) -> Result<usize, ErrorStack> {
        unsafe {
            let mut sig_len = sig_buf.len();
            cvt(ffi::EVP_DigestSign(
                self.md_ctx,
                sig_buf.as_mut_ptr() as *mut _,
                &mut sig_len,
                data_buf.as_ptr() as *const _,
                data_buf.len(),
            ))?;
            Ok(sig_len)
        }
    }

    /// Returns the signature.
    ///
    /// This is a simple convenience wrapper over `len` and `sign_oneshot`.
    #[cfg(ossl111)]
    pub fn sign_oneshot_to_vec(&mut self, data_buf: &[u8]) -> Result<Vec<u8>, ErrorStack> {
        let mut sig_buf = vec![0; self.len()?];
        let len = self.sign_oneshot(&mut sig_buf, data_buf)?;
        // The advertised length is not always equal to the real length for things like DSA
        sig_buf.truncate(len);
        Ok(sig_buf)
    }
}

impl<'a> Write for Signer<'a> {
    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
        self.update(buf)?;
        Ok(buf.len())
    }

    fn flush(&mut self) -> io::Result<()> {
        Ok(())
    }
}

/// A type which can be used to verify the integrity and authenticity
/// of data given the signature.
pub struct Verifier<'a> {
    md_ctx: *mut ffi::EVP_MD_CTX,
    pctx: *mut ffi::EVP_PKEY_CTX,
    pkey_pd: PhantomData<&'a ()>,
}

unsafe impl<'a> Sync for Verifier<'a> {}
unsafe impl<'a> Send for Verifier<'a> {}

impl<'a> Drop for Verifier<'a> {
    fn drop(&mut self) {
        // pkey_ctx is owned by the md_ctx, so no need to explicitly free it.
        unsafe {
            EVP_MD_CTX_free(self.md_ctx);
        }
    }
}

/// A type which verifies cryptographic signatures of data.
impl<'a> Verifier<'a> {
    /// Creates a new `Verifier`.
    ///
    /// This cannot be used with Ed25519 or Ed448 keys. Please refer to
    /// [`Verifier::new_without_digest`].
    ///
    /// OpenSSL documentation at [`EVP_DigestVerifyInit`].
    ///
    /// [`EVP_DigestVerifyInit`]: https://www.openssl.org/docs/manmaster/man3/EVP_DigestVerifyInit.html
    pub fn new<T>(type_: MessageDigest, pkey: &'a PKeyRef<T>) -> Result<Verifier<'a>, ErrorStack>
    where
        T: HasPublic,
    {
        Verifier::new_intern(Some(type_), pkey)
    }

    /// Creates a new `Verifier` without a digest.
    ///
    /// This is the only way to create a `Verifier` for Ed25519 or Ed448 keys.
    ///
    /// OpenSSL documentation at [`EVP_DigestVerifyInit`].
    ///
    /// [`EVP_DigestVerifyInit`]: https://www.openssl.org/docs/manmaster/man3/EVP_DigestVerifyInit.html
    pub fn new_without_digest<T>(pkey: &'a PKeyRef<T>) -> Result<Verifier<'a>, ErrorStack>
    where
        T: HasPublic,
    {
        Verifier::new_intern(None, pkey)
    }

    fn new_intern<T>(
        type_: Option<MessageDigest>,
        pkey: &'a PKeyRef<T>,
    ) -> Result<Verifier<'a>, ErrorStack>
    where
        T: HasPublic,
    {
        unsafe {
            ffi::init();

            let ctx = cvt_p(EVP_MD_CTX_new())?;
            let mut pctx: *mut ffi::EVP_PKEY_CTX = ptr::null_mut();
            let r = ffi::EVP_DigestVerifyInit(
                ctx,
                &mut pctx,
                type_.map(|t| t.as_ptr()).unwrap_or(ptr::null()),
                ptr::null_mut(),
                pkey.as_ptr(),
            );
            if r != 1 {
                EVP_MD_CTX_free(ctx);
                return Err(ErrorStack::get());
            }

            assert!(!pctx.is_null());

            Ok(Verifier {
                md_ctx: ctx,
                pctx,
                pkey_pd: PhantomData,
            })
        }
    }

    /// Returns the RSA padding mode in use.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to `EVP_PKEY_CTX_get_rsa_padding`.
    pub fn rsa_padding(&self) -> Result<Padding, ErrorStack> {
        unsafe {
            let mut pad = 0;
            cvt(ffi::EVP_PKEY_CTX_get_rsa_padding(self.pctx, &mut pad))
                .map(|_| Padding::from_raw(pad))
        }
    }

    /// Sets the RSA padding mode.
    ///
    /// This is only useful for RSA keys.
    ///
    /// This corresponds to [`EVP_PKEY_CTX_set_rsa_padding`].
    ///
    /// [`EVP_PKEY_CTX_set_rsa_padding`]: https://www.openssl.org/docs/man1.1.0/crypto/EVP_PKEY_CTX_set_rsa_padding.html
    pub fn set_rsa_padding(&mut self, padding: Padding) -> Result<(), ErrorStack> {
        unsafe {
            cvt(ffi::EVP_PKEY_CTX_set_rsa_padding(
                self.pctx,
                padding.as_raw(),
            ))
            .map(|_| ())
        }
    }

Trait Implementations

impl Clone for Padding

fn clone(&self) -> Padding

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Padding

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq<Padding> for Padding

fn eq(&self, other: &Padding) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Padding

impl Eq for Padding

impl StructuralEq for Padding

impl StructuralPartialEq for Padding