| SSL_get_error.pod (68651) | SSL_get_error.pod (72613) |
|---|---|
| 1=pod 2 3=head1 NAME 4 5SSL_get_error - obtain result code for TLS/SSL I/O operation 6 7=head1 SYNOPSIS 8 9 #include <openssl/ssl.h> 10 11 int SSL_get_error(SSL *ssl, int ret); 12 13=head1 DESCRIPTION 14 15SSL_get_error() returns a result code (suitable for the C "switch" 16statement) for a preceding call to SSL_connect(), SSL_accept(), | 1=pod 2 3=head1 NAME 4 5SSL_get_error - obtain result code for TLS/SSL I/O operation 6 7=head1 SYNOPSIS 8 9 #include <openssl/ssl.h> 10 11 int SSL_get_error(SSL *ssl, int ret); 12 13=head1 DESCRIPTION 14 15SSL_get_error() returns a result code (suitable for the C "switch" 16statement) for a preceding call to SSL_connect(), SSL_accept(), |
| 17SSL_read(), or SSL_write() on B<ssl>. The value returned by that 18TLS/SSL I/O function must be passed to SSL_get_error() in parameter | 17SSL_read(), SSL_peek(), or SSL_write() on B<ssl>. The value returned by 18that TLS/SSL I/O function must be passed to SSL_get_error() in parameter |
| 19B<ret>. 20 21In addition to B<ssl> and B<ret>, SSL_get_error() inspects the 22current thread's OpenSSL error queue. Thus, SSL_get_error() must be 23used in the same thread that performed the TLS/SSL I/O operation, and no 24other OpenSSL function calls should appear in between. The current 25thread's error queue must be empty before the TLS/SSL I/O operation is 26attempted, or SSL_get_error() will not work reliably. --- 16 unchanged lines hidden (view full) --- 43alert has occurred in the protocol, i.e. if the connection has been 44closed cleanly. Note that in this case B<SSL_ERROR_ZERO_RETURN> 45does not necessarily indicate that the underlying transport 46has been closed. 47 48=item SSL_ERROR_WANT_READ, SSL_ERROR_WANT_WRITE 49 50The operation did not complete; the same TLS/SSL I/O function should be | 19B<ret>. 20 21In addition to B<ssl> and B<ret>, SSL_get_error() inspects the 22current thread's OpenSSL error queue. Thus, SSL_get_error() must be 23used in the same thread that performed the TLS/SSL I/O operation, and no 24other OpenSSL function calls should appear in between. The current 25thread's error queue must be empty before the TLS/SSL I/O operation is 26attempted, or SSL_get_error() will not work reliably. --- 16 unchanged lines hidden (view full) --- 43alert has occurred in the protocol, i.e. if the connection has been 44closed cleanly. Note that in this case B<SSL_ERROR_ZERO_RETURN> 45does not necessarily indicate that the underlying transport 46has been closed. 47 48=item SSL_ERROR_WANT_READ, SSL_ERROR_WANT_WRITE 49 50The operation did not complete; the same TLS/SSL I/O function should be |
| 51called again later. There will be protocol progress if, by then, the 52underlying B<BIO> has data available for reading (if the result code is 53B<SSL_ERROR_WANT_READ>) or allows writing data (B<SSL_ERROR_WANT_WRITE>). 54For socket B<BIO>s (e.g. when SSL_set_fd() was used) this means that 55select() or poll() on the underlying socket can be used to find out 56when the TLS/SSL I/O function should be retried. | 51called again later. If, by then, the underlying B<BIO> has data 52available for reading (if the result code is B<SSL_ERROR_WANT_READ>) 53or allows writing data (B<SSL_ERROR_WANT_WRITE>), then some TLS/SSL 54protocol progress will take place, i.e. at least part of an TLS/SSL 55record will be read or written. Note that the retry may again lead to 56a B<SSL_ERROR_WANT_READ> or B<SSL_ERROR_WANT_WRITE> condition. 57There is no fixed upper limit for the number of iterations that 58may be necessary until progress becomes visible at application 59protocol level. |
| 57 | 60 |
| 61For socket B<BIO>s (e.g. when SSL_set_fd() was used), select() or 62poll() on the underlying socket can be used to find out when the 63TLS/SSL I/O function should be retried. 64 |
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| 58Caveat: Any TLS/SSL I/O function can lead to either of | 65Caveat: Any TLS/SSL I/O function can lead to either of |
| 59B<SSL_ERROR_WANT_READ> and B<SSL_ERROR_WANT_WRITE>, i.e. SSL_read() 60may want to write data and SSL_write() may want to read data. | 66B<SSL_ERROR_WANT_READ> and B<SSL_ERROR_WANT_WRITE>. In particular, 67SSL_read() or SSL_peek() may want to write data and SSL_write() may want 68to read data. This is mainly because TLS/SSL handshakes may occur at any 69time during the protocol (initiated by either the client or the server); 70SSL_read(), SSL_peek(), and SSL_write() will handle any pending handshakes. |
| 61 62=item SSL_ERROR_WANT_X509_LOOKUP 63 64The operation did not complete because an application callback set by 65SSL_CTX_set_client_cert_cb() has asked to be called again. 66The TLS/SSL I/O function should be called again later. 67Details depend on the application. 68 --- 25 unchanged lines hidden --- | 71 72=item SSL_ERROR_WANT_X509_LOOKUP 73 74The operation did not complete because an application callback set by 75SSL_CTX_set_client_cert_cb() has asked to be called again. 76The TLS/SSL I/O function should be called again later. 77Details depend on the application. 78 --- 25 unchanged lines hidden --- |