SSLgeterror(3) OpenSSL SSLgeterror(3)

NAME
       SSLgeterror - obtain result code for TLS/SSL I/O operation

SYNOPSIS
        #include 

        int SSLgeterror(const SSL *ssl, int ret);

DESCRIPTION
       SSLgeterror() returns a result code (suitable for the C "switch"
       statement) for a preceding call to SSLconnect(), SSLaccept(),
       SSLdohandshake(), SSLread(), SSLpeek(), or SSLwrite() on ssssll.  The
       value returned by that TLS/SSL I/O function must be passed to
       SSLgeterror() in parameter rreett.

       In addition to ssssll and rreett, SSLgeterror() inspects the current
       thread's OpenSSL error queue.  Thus, SSLgeterror() must be used in
       the same thread that performed the TLS/SSL I/O operation, and no other
       OpenSSL function calls should appear in between.  The current thread's
       error queue must be empty before the TLS/SSL I/O operation is
       attempted, or SSLgeterror() will not work reliably.

RETURN VALUES
       The following return values can currently occur:

       SSLERRORNONE
           The TLS/SSL I/O operation completed.  This result code is returned
           if and only if rreett >> 00.

       SSLERRORZERORETURN
           The TLS/SSL connection has been closed.  If the protocol version is
           SSL 3.0 or TLS 1.0, this result code is returned only if a closure
           alert has occurred in the protocol, i.e. if the connection has been
           closed cleanly. Note that in this case SSSSLLEERRRROORRZZEERROORREETTUURRNN does
           not necessarily indicate that the underlying transport has been
           closed.

       SSLERRORWANTREAD, SSLERRORWANTWRITE
           The operation did not complete; the same TLS/SSL I/O function
           should be called again later.  If, by then, the underlying BBIIOO has
           data available for reading (if the result code is
           SSSSLLEERRRROORRWWAANNTTRREEAADD) or allows writing data (SSSSLLEERRRROORRWWAANNTTWWRRIITTEE),
           then some TLS/SSL protocol progress will take place, i.e. at least
           part of an TLS/SSL record will be read or written.  Note that the
           retry may again lead to a SSSSLLEERRRROORRWWAANNTTRREEAADD or
           SSSSLLEERRRROORRWWAANNTTWWRRIITTEE condition.  There is no fixed upper limit for
           the number of iterations that may be necessary until progress
           becomes visible at application protocol level.

           For socket BBIIOOs (e.g. when SSLsetfd() was used), select() or
           poll() on the underlying socket can be used to find out when the
           TLS/SSL I/O function should be retried.

           Caveat: Any TLS/SSL I/O function can lead to either of
           SSSSLLEERRRROORRWWAANNTTRREEAADD and SSSSLLEERRRROORRWWAANNTTWWRRIITTEE.  In particular,
           SSLread() or SSLpeek() may want to write data and SSLwrite() may
           want to read data.  This is mainly because TLS/SSL handshakes may
           occur at any time during the protocol (initiated by either the
           client or the server); SSLread(), SSLpeek(), and SSLwrite() will
           handle any pending handshakes.

       SSLERRORWANTCONNECT, SSLERRORWANTACCEPT
           The operation did not complete; the same TLS/SSL I/O function
           should be called again later. The underlying BIO was not connected
           yet to the peer and the call would block in connect()/accept(). The
           SSL function should be called again when the connection is
           established. These messages can only appear with a BIOsconnect()
           or BIOsaccept() BIO, respectively.  In order to find out, when
           the connection has been successfully established, on many platforms
           select() or poll() for writing on the socket file descriptor can be
           used.

       SSLERRORWANTX509LOOKUP
           The operation did not complete because an application callback set
           by SSLCTXsetclientcertcb() has asked to be called again.  The
           TLS/SSL I/O function should be called again later.  Details depend
           on the application.

       SSLERRORSYSCALL
           Some I/O error occurred.  The OpenSSL error queue may contain more
           information on the error.  If the error queue is empty (i.e.
           ERRgeterror() returns 0), rreett can be used to find out more about
           the error: If rreett ==== 00, an EOF was observed that violates the
           protocol.  If rreett ==== -11, the underlying BBIIOO reported an I/O error
           (for socket I/O on Unix systems, consult eerrrrnnoo for details).

       SSLERRORSSL
           A failure in the SSL library occurred, usually a protocol error.
           The OpenSSL error queue contains more information on the error.

SEE ALSO
       ssl(3), err(3)

HISTORY       SSLgeterror() was added in SSLeay 0.8.



0.9.7l                            2005-03-30                  SSLgeterror(3)