1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
use ffi;
use libc::c_int;
use std::error;
use std::error::Error as StdError;
use std::fmt;
use std::io;

use error::ErrorStack;
use ssl::MidHandshakeSslStream;
use x509::X509VerifyResult;

/// An error code returned from SSL functions.
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub struct ErrorCode(c_int);

impl ErrorCode {
    pub fn from_raw(raw: c_int) -> ErrorCode {
        ErrorCode(raw)
    }

    pub fn as_raw(&self) -> c_int {
        self.0
    }

    /// The SSL session has been closed.
    pub const ZERO_RETURN: ErrorCode = ErrorCode(ffi::SSL_ERROR_ZERO_RETURN);

    /// An attempt to read data from the underlying socket returned `WouldBlock`.
    ///
    /// Wait for read readiness and retry the operation.
    pub const WANT_READ: ErrorCode = ErrorCode(ffi::SSL_ERROR_WANT_READ);

    /// An attempt to write data to the underlying socket returned `WouldBlock`.
    ///
    /// Wait for write readiness and retry the operation.
    pub const WANT_WRITE: ErrorCode = ErrorCode(ffi::SSL_ERROR_WANT_WRITE);

    /// A non-recoverable IO error occurred.
    pub const SYSCALL: ErrorCode = ErrorCode(ffi::SSL_ERROR_SYSCALL);

    /// An error occurred in the SSL library.
    pub const SSL: ErrorCode = ErrorCode(ffi::SSL_ERROR_SSL);

    /// The client hello callback indicated that it needed to be retried.
    ///
    /// Requires OpenSSL 1.1.1 or newer.
    #[cfg(ossl111)]
    pub const WANT_CLIENT_HELLO_CB: ErrorCode = ErrorCode(ffi::SSL_ERROR_WANT_CLIENT_HELLO_CB);
}

#[derive(Debug)]
pub(crate) enum InnerError {
    Io(io::Error),
    Ssl(ErrorStack),
}

/// An SSL error.
#[derive(Debug)]
pub struct Error {
    pub(crate) code: ErrorCode,
    pub(crate) cause: Option<InnerError>,
}

impl Error {
    pub fn code(&self) -> ErrorCode {
        self.code
    }

    pub fn io_error(&self) -> Option<&io::Error> {
        match self.cause {
            Some(InnerError::Io(ref e)) => Some(e),
            _ => None,
        }
    }

    pub fn into_io_error(self) -> Result<io::Error, Error> {
        match self.cause {
            Some(InnerError::Io(e)) => Ok(e),
            _ => Err(self),
        }
    }

    pub fn ssl_error(&self) -> Option<&ErrorStack> {
        match self.cause {
            Some(InnerError::Ssl(ref e)) => Some(e),
            _ => None,
        }
    }
}

impl From<ErrorStack> for Error {
    fn from(e: ErrorStack) -> Error {
        Error {
            code: ErrorCode::SSL,
            cause: Some(InnerError::Ssl(e)),
        }
    }
}

impl fmt::Display for Error {
    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
        match self.code {
            ErrorCode::ZERO_RETURN => fmt.write_str("the SSL session has been shut down"),
            ErrorCode::WANT_READ => match self.io_error() {
                Some(_) => fmt.write_str("a nonblocking read call would have blocked"),
                None => fmt.write_str("the operation should be retried"),
            },
            ErrorCode::WANT_WRITE => match self.io_error() {
                Some(_) => fmt.write_str("a nonblocking write call would have blocked"),
                None => fmt.write_str("the operation should be retried"),
            },
            ErrorCode::SYSCALL => match self.io_error() {
                Some(err) => write!(fmt, "{}", err),
                None => fmt.write_str("unexpected EOF"),
            },
            ErrorCode::SSL => match self.ssl_error() {
                Some(e) => write!(fmt, "{}", e),
                None => fmt.write_str("OpenSSL error"),
            },
            ErrorCode(code) => write!(fmt, "unknown error code {}", code),
        }
    }
}

impl error::Error for Error {
    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
        match self.cause {
            Some(InnerError::Io(ref e)) => Some(e),
            Some(InnerError::Ssl(ref e)) => Some(e),
            None => None,
        }
    }
}

/// An error or intermediate state after a TLS handshake attempt.
// FIXME overhaul
#[derive(Debug)]
pub enum HandshakeError<S> {
    /// Setup failed.
    SetupFailure(ErrorStack),
    /// The handshake failed.
    Failure(MidHandshakeSslStream<S>),
    /// The handshake encountered a `WouldBlock` error midway through.
    ///
    /// This error will never be returned for blocking streams.
    WouldBlock(MidHandshakeSslStream<S>),
}

impl<S: fmt::Debug> StdError for HandshakeError<S> {
    fn source(&self) -> Option<&(dyn StdError + 'static)> {
        match *self {
            HandshakeError::SetupFailure(ref e) => Some(e),
            HandshakeError::Failure(ref s) | HandshakeError::WouldBlock(ref s) => Some(s.error()),
        }
    }
}

impl<S: fmt::Debug> fmt::Display for HandshakeError<S> {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match *self {
            HandshakeError::SetupFailure(ref e) => write!(f, "stream setup failed: {}", e)?,
            HandshakeError::Failure(ref s) => {
                write!(f, "the handshake failed: {}", s.error())?;
                let verify = s.ssl().verify_result();
                if verify != X509VerifyResult::OK {
                    write!(f, ": {}", verify)?;
                }
            }
            HandshakeError::WouldBlock(ref s) => {
                write!(f, "the handshake was interrupted: {}", s.error())?;
                let verify = s.ssl().verify_result();
                if verify != X509VerifyResult::OK {
                    write!(f, ": {}", verify)?;
                }
            }
        }
        Ok(())
    }
}

impl<S> From<ErrorStack> for HandshakeError<S> {
    fn from(e: ErrorStack) -> HandshakeError<S> {
        HandshakeError::SetupFailure(e)
    }
}