/* * Provides IO functions to interface between the BIO buffers and TCL * applications when using stacked channels. * * Copyright (C) 1997-2000 Matt Newman <[email protected]> * Copyright (C) 2000 Ajuba Solutions * Copyright (C) 2024 Brian O'Hagan * * Additional credit is due for Andreas Kupries ([email protected]), for * providing the Tcl_ReplaceChannel mechanism and working closely with me * to enhance it to support full fileevent semantics. * * Also work done by the follow people provided the impetus to do this "right": * tclSSL (Colin McCormack, Shared Technology) * SSLtcl (Peter Antman) * */ /* tlsBIO.c tlsIO.c +------+ +-----+ +------+ | |Tcl_WriteRaw <-- BioWrite| SSL |BIO_write <-- TlsOutputProc <-- Write| | |socket| <encrypted> | BIO | <unencrypted> | App | | |Tcl_ReadRaw --> BioRead| |BIO_Read --> TlsInputProc --> Read| | +------+ +-----+ +------+ */ #include "tlsInt.h" #include <errno.h> /* *----------------------------------------------------------------------------- * * TlsBlockModeProc -- * * This procedure is invoked by the generic IO level to set channel to * blocking or nonblocking mode. Called by the generic I/O layer whenever * the Tcl_SetChannelOption() function is used with option -blocking. * * Results: * 0 if successful or POSIX error code if failed. * * Side effects: * Sets the device into blocking or nonblocking mode. * *----------------------------------------------------------------------------- */ static int TlsBlockModeProc(ClientData instanceData, int mode) { State *statePtr = (State *) instanceData; if (mode == TCL_MODE_NONBLOCKING) { statePtr->flags |= TLS_TCL_ASYNC; } else { statePtr->flags &= ~(TLS_TCL_ASYNC); } return 0; } /* *----------------------------------------------------------------------------- * * TlsCloseProc -- * * This procedure is invoked by the generic IO level to perform channel * type specific cleanup when a SSL socket based channel is closed. * Called by the generic I/O layer whenever the Tcl_Close() function is * used. * * Results: * 0 if successful or POSIX error code if failed. * * Side effects: * Closes the socket of the channel. * *----------------------------------------------------------------------------- */ static int TlsCloseProc(ClientData instanceData, Tcl_Interp *interp) { State *statePtr = (State *) instanceData; dprintf("TlsCloseProc(%p)", (void *) statePtr); /* Flush any pending data */ /* Send shutdown notification. Will return 0 while in process, then 1 when complete. */ /* Closes the write direction of the connection; the read direction is closed by the peer. */ /* Does not affect socket state. Don't call after fatal error. */ if (statePtr->ssl != NULL && !(statePtr->flags & TLS_TCL_HANDSHAKE_FAILED)) { SSL_shutdown(statePtr->ssl); } /* Tls_Free calls Tls_Clean */ Tcl_EventuallyFree((ClientData)statePtr, Tls_Free); return 0; } /* *----------------------------------------------------------------------------- * * TlsClose2Proc -- * * Similar to TlsCloseProc, but allows for separate close read and write * side of channel. * *----------------------------------------------------------------------------- */ static int TlsClose2Proc(ClientData instanceData, /* The socket state. */ Tcl_Interp *interp, /* For errors - can be NULL. */ int flags) /* Flags to close read and/or write side of channel */ { State *statePtr = (State *) instanceData; dprintf("TlsClose2Proc(%p)", (void *) statePtr); if ((flags & (TCL_CLOSE_READ|TCL_CLOSE_WRITE)) == 0) { return TlsCloseProc(instanceData, interp); } return EINVAL; } /* *----------------------------------------------------------------------------- * * Tls_WaitForConnect -- * * Perform connect (client) or accept (server) function. Also performs * equivalent of handshake function. * * Result: * 1 if successful, 0 if wait for connect, and -1 if failed. * * Side effects: * Issues SSL_accept or SSL_connect * *----------------------------------------------------------------------------- */ int Tls_WaitForConnect(State *statePtr, int *errorCodePtr, int handshakeFailureIsPermanent) { unsigned long backingError; int err, rc = 0; int bioShouldRetry; *errorCodePtr = 0; dprintf("WaitForConnect(%p)", (void *) statePtr); dprintFlags(statePtr); /* Can also check SSL_is_init_finished(ssl) */ if (!(statePtr->flags & TLS_TCL_INIT)) { dprintf("Tls_WaitForConnect called on already initialized channel -- returning with immediate success"); return 1; } if (statePtr->flags & TLS_TCL_HANDSHAKE_FAILED) { /* * Different types of operations have different requirements * SSL being established */ if (handshakeFailureIsPermanent) { dprintf("Asked to wait for a TLS handshake that has already failed. Returning fatal error"); *errorCodePtr = ECONNABORTED; } else { dprintf("Asked to wait for a TLS handshake that has already failed. Returning soft error"); *errorCodePtr = ECONNRESET; } Tls_Error(statePtr, "Wait for failed handshake"); return -1; } for (;;) { ERR_clear_error(); BIO_clear_retry_flags(statePtr->bio); /* Not initialized yet! Also calls SSL_do_handshake(). */ if (statePtr->flags & TLS_TCL_SERVER) { dprintf("Calling SSL_accept()"); err = SSL_accept(statePtr->ssl); } else { dprintf("Calling SSL_connect()"); err = SSL_connect(statePtr->ssl); } /* 1=successful, 0=not successful and shut down, <0=fatal error */ if (err > 0) { dprintf("Accept or connect was successful"); err = BIO_flush(statePtr->bio); if (err <= 0) { dprintf("Flushing the lower layers failed, this will probably terminate this session"); } } else { dprintf("Accept or connect failed"); } /* Same as SSL_want, but also checks the error queue */ rc = SSL_get_error(statePtr->ssl, err); backingError = ERR_get_error(); if (rc != SSL_ERROR_NONE) { dprintf("Got error: %i (rc = %i)", err, rc); dprintf("Got error: %s", ERR_reason_error_string(backingError)); } /* The retry flag is set by the BIO_set_retry_* functions */ bioShouldRetry = BIO_should_retry(statePtr->bio); dprintf("bioShouldRetry = %d", bioShouldRetry); if (err <= 0) { if (rc == SSL_ERROR_WANT_CONNECT || rc == SSL_ERROR_WANT_ACCEPT) { bioShouldRetry = 1; } else if (rc == SSL_ERROR_WANT_READ) { bioShouldRetry = 1; statePtr->want |= TCL_READABLE; } else if (rc == SSL_ERROR_WANT_WRITE) { bioShouldRetry = 1; statePtr->want |= TCL_WRITABLE; } else if (BIO_should_retry(statePtr->bio)) { bioShouldRetry = 1; } else if (rc == SSL_ERROR_SYSCALL && Tcl_GetErrno() == EAGAIN) { bioShouldRetry = 1; } } if (bioShouldRetry) { dprintf("The I/O did not complete -- but we should try it again"); if (statePtr->flags & TLS_TCL_ASYNC) { dprintf("Returning EAGAIN so that it can be retried later"); *errorCodePtr = EAGAIN; return 0; } else { dprintf("Doing so now"); continue; } } dprintf("We have either completely established the session or completely failed it -- there is no more need to ever retry it though"); break; } switch (rc) { case SSL_ERROR_NONE: /* The TLS/SSL I/O operation completed successfully */ dprintf("The connection is good"); *errorCodePtr = 0; break; case SSL_ERROR_SSL: /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */ /* This includes certificate validation errors */ dprintf("SSL_ERROR_SSL: Got permanent fatal SSL error, aborting immediately"); if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) { Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl))); } if (backingError != 0) { Tls_Error(statePtr, ERR_reason_error_string(backingError)); } statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED; *errorCodePtr = ECONNABORTED; return -1; case SSL_ERROR_SYSCALL: /* Some non-recoverable, fatal I/O error occurred */ dprintf("SSL_ERROR_SYSCALL"); if (backingError == 0 && err == 0) { dprintf("EOF reached") *errorCodePtr = ECONNRESET; Tls_Error(statePtr, "(unexpected) EOF reached"); } else if (backingError == 0 && err == -1) { dprintf("I/O error occurred (errno = %lu)", (unsigned long) Tcl_GetErrno()); *errorCodePtr = Tcl_GetErrno(); if (*errorCodePtr == ECONNRESET) { *errorCodePtr = ECONNABORTED; } Tls_Error(statePtr, Tcl_ErrnoMsg(*errorCodePtr)); } else { dprintf("I/O error occurred (backingError = %lu)", backingError); *errorCodePtr = Tcl_GetErrno(); if (*errorCodePtr == ECONNRESET) { *errorCodePtr = ECONNABORTED; } Tls_Error(statePtr, ERR_reason_error_string(backingError)); } statePtr->flags |= TLS_TCL_HANDSHAKE_FAILED; return -1; case SSL_ERROR_ZERO_RETURN: /* Peer has closed the connection by sending the close_notify alert. Can't read, but can write. */ /* Need to return an EOF, so channel is closed which will send an SSL_shutdown(). */ dprintf("SSL_ERROR_ZERO_RETURN: Connect returned an invalid value..."); *errorCodePtr = ECONNRESET; Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert"); return -1; case SSL_ERROR_WANT_READ: /* More data must be read from the underlying BIO layer in order to complete the actual SSL_*() operation. */ dprintf("SSL_ERROR_WANT_READ"); BIO_set_retry_read(statePtr->bio); *errorCodePtr = EAGAIN; dprintf("ERR(SSL_ERROR_ZERO_RETURN, EAGAIN) "); statePtr->want |= TCL_READABLE; return 0; case SSL_ERROR_WANT_WRITE: /* There is data in the SSL buffer that must be written to the underlying BIO in order to complete the SSL_*() operation. */ dprintf("SSL_ERROR_WANT_WRITE"); BIO_set_retry_write(statePtr->bio); *errorCodePtr = EAGAIN; dprintf("ERR(SSL_ERROR_WANT_WRITE, EAGAIN) "); statePtr->want |= TCL_WRITABLE; return 0; case SSL_ERROR_WANT_CONNECT: /* Connect would have blocked. */ dprintf("SSL_ERROR_WANT_CONNECT"); BIO_set_retry_special(statePtr->bio); BIO_set_retry_reason(statePtr->bio, BIO_RR_CONNECT); *errorCodePtr = EAGAIN; dprintf("ERR(SSL_ERROR_WANT_CONNECT, EAGAIN) "); return 0; case SSL_ERROR_WANT_ACCEPT: /* Accept would have blocked */ dprintf("SSL_ERROR_WANT_ACCEPT"); BIO_set_retry_special(statePtr->bio); BIO_set_retry_reason(statePtr->bio, BIO_RR_ACCEPT); *errorCodePtr = EAGAIN; dprintf("ERR(SSL_ERROR_WANT_ACCEPT, EAGAIN) "); return 0; case SSL_ERROR_WANT_X509_LOOKUP: /* App callback set by SSL_CTX_set_client_cert_cb has asked to be called again */ /* The operation did not complete because an application callback set by SSL_CTX_set_client_cert_cb() has asked to be called again. */ dprintf("SSL_ERROR_WANT_X509_LOOKUP"); BIO_set_retry_special(statePtr->bio); BIO_set_retry_reason(statePtr->bio, BIO_RR_SSL_X509_LOOKUP); *errorCodePtr = EAGAIN; dprintf("ERR(SSL_ERROR_WANT_X509_LOOKUP, EAGAIN) "); return 0; case SSL_ERROR_WANT_ASYNC: /* Used with flag SSL_MODE_ASYNC, op didn't complete because an async engine is still processing data */ case SSL_ERROR_WANT_ASYNC_JOB: /* The asynchronous job could not be started because there were no async jobs available in the pool. */ case SSL_ERROR_WANT_CLIENT_HELLO_CB: /* The operation did not complete because an application callback set by SSL_CTX_set_client_hello_cb() has asked to be called again. */ #if OPENSSL_VERSION_NUMBER >= 0x30000000L case SSL_ERROR_WANT_RETRY_VERIFY: /* The operation did not complete because a certificate verification callback has asked to be called again via SSL_set_retry_verify(3). */ #endif default: /* The operation did not complete and should be retried later. */ dprintf("Operation did not complete, call function again later"); *errorCodePtr = EAGAIN; dprintf("ERR(Other, EAGAIN) "); return 0; } dprintf("Removing the \"TLS_TCL_INIT\" flag since we have completed the handshake"); statePtr->flags &= ~TLS_TCL_INIT; dprintf("Returning success"); *errorCodePtr = 0; return 1; } /* *----------------------------------------------------------------------------- * * TlsInputProc -- * * This procedure is invoked by the generic I/O layer to read data from * the BIO whenever the Tcl_Read(), Tcl_ReadChars, Tcl_Gets, and * Tcl_GetsObj functions are used. Equivalent to SSL_read_ex and SSL_read. * * Results: * Returns the number of bytes read or -1 on error. Sets errorCodePtr to * a POSIX error code if an error occurred, or 0 if none. * * Side effects: * Reads input from the input device of the channel. * * Data is received in whole blocks known as records from the peer. A whole * record is processed (e.g. decrypted) in one go and is buffered by OpenSSL * until it is read by the application via a call to SSL_read. * *----------------------------------------------------------------------------- */ static int TlsInputProc(ClientData instanceData, char *buf, int bufSize, int *errorCodePtr) { unsigned long backingError; State *statePtr = (State *) instanceData; int bytesRead, err; *errorCodePtr = 0; dprintf("Read(%d)", bufSize); /* Skip if user verify callback is still running */ if (statePtr->flags & TLS_TCL_CALLBACK) { dprintf("Callback is running, reading 0 bytes"); return 0; } /* If not initialized, do connect */ /* Can also check SSL_is_init_finished(ssl) */ if (statePtr->flags & TLS_TCL_INIT) { int tlsConnect; dprintf("Calling Tls_WaitForConnect"); tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 0); if (tlsConnect < 0) { dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr); bytesRead = -1; if (*errorCodePtr == ECONNRESET) { dprintf("Got connection reset"); /* Soft EOF */ *errorCodePtr = 0; bytesRead = 0; } return bytesRead; } } /* * We need to clear the SSL error stack now because we sometimes reach * this function with leftover errors in the stack. If BIO_read * returns -1 and intends EAGAIN, there is a leftover error, it will be * misconstrued as an error, not EAGAIN. * * Alternatively, we may want to handle the <0 return codes from * BIO_read specially (as advised in the RSA docs). TLS's lower level BIO * functions play with the retry flags though, and this seems to work * correctly. Similar fix in TlsOutputProc. - hobbs */ ERR_clear_error(); BIO_clear_retry_flags(statePtr->bio); bytesRead = BIO_read(statePtr->bio, buf, bufSize); dprintf("BIO_read -> %d", bytesRead); /* Same as SSL_want, but also checks the error queue */ err = SSL_get_error(statePtr->ssl, bytesRead); backingError = ERR_get_error(); if (bytesRead <= 0) { /* The retry flag is set by the BIO_set_retry_* functions */ if (BIO_should_retry(statePtr->bio)) { dprintf("Read failed with code=%d, bytes read=%d: should retry", err, bytesRead); /* Some docs imply we should redo the BIO_read now */ } else { dprintf("Read failed with code=%d, bytes read=%d: error condition", err, bytesRead); } dprintf("BIO is EOF %d", BIO_eof(statePtr->bio)); /* These are the same as BIO_retry_type */ if (BIO_should_read(statePtr->bio)) { dprintf("BIO has insufficient data to read and return"); statePtr->want |= TCL_READABLE; } if (BIO_should_write(statePtr->bio)) { dprintf("BIO has pending data to write"); statePtr->want |= TCL_WRITABLE; } if (BIO_should_io_special(statePtr->bio)) { int reason = BIO_get_retry_reason(statePtr->bio); dprintf("BIO has some special condition other than read or write: code=%d", reason); } dprintf("BIO has pending data to write"); } switch (err) { case SSL_ERROR_NONE: /* I/O operation completed */ dprintf("SSL_ERROR_NONE"); dprintBuffer(buf, bytesRead); break; case SSL_ERROR_SSL: /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */ dprintf("SSL error, indicating that the connection has been aborted"); if (backingError != 0) { Tls_Error(statePtr, ERR_reason_error_string(backingError)); } else if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) { Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl))); } else { Tls_Error(statePtr, "Unknown SSL error"); } *errorCodePtr = ECONNABORTED; bytesRead = -1; #if OPENSSL_VERSION_NUMBER >= 0x30000000L /* Unexpected EOF from the peer for OpenSSL 3.0+ */ if (ERR_GET_REASON(backingError) == SSL_R_UNEXPECTED_EOF_WHILE_READING) { dprintf("(Unexpected) EOF reached") *errorCodePtr = 0; bytesRead = 0; Tls_Error(statePtr, "EOF reached"); } #endif break; case SSL_ERROR_WANT_READ: /* Op did not complete due to not enough data was available. Retry later. */ dprintf("Got SSL_ERROR_WANT_READ, mapping this to EAGAIN"); *errorCodePtr = EAGAIN; bytesRead = -1; statePtr->want |= TCL_READABLE; BIO_set_retry_read(statePtr->bio); break; case SSL_ERROR_WANT_WRITE: /* Op did not complete due to unable to send all data to the BIO. Retry later. */ dprintf("Got SSL_ERROR_WANT_WRITE, mapping this to EAGAIN"); *errorCodePtr = EAGAIN; bytesRead = -1; statePtr->want |= TCL_WRITABLE; BIO_set_retry_write(statePtr->bio); break; case SSL_ERROR_WANT_X509_LOOKUP: /* Op didn't complete since callback set by SSL_CTX_set_client_cert_cb() asked to be called again */ dprintf("Got SSL_ERROR_WANT_X509_LOOKUP, mapping it to EAGAIN"); *errorCodePtr = EAGAIN; bytesRead = -1; break; case SSL_ERROR_SYSCALL: /* Some non-recoverable, fatal I/O error occurred */ dprintf("SSL_ERROR_SYSCALL"); if (backingError == 0 && bytesRead == 0) { /* Unexpected EOF from the peer for OpenSSL 1.1 */ dprintf("(Unexpected) EOF reached") *errorCodePtr = 0; bytesRead = 0; Tls_Error(statePtr, "EOF reached"); } else if (backingError == 0 && bytesRead == -1) { dprintf("I/O error occurred (errno = %lu)", (unsigned long) Tcl_GetErrno()); *errorCodePtr = Tcl_GetErrno(); bytesRead = -1; Tls_Error(statePtr, Tcl_ErrnoMsg(*errorCodePtr)); } else { dprintf("I/O error occurred (backingError = %lu)", backingError); *errorCodePtr = Tcl_GetErrno(); bytesRead = -1; Tls_Error(statePtr, ERR_reason_error_string(backingError)); } break; case SSL_ERROR_ZERO_RETURN: /* Peer has closed the connection by sending the close_notify alert. Can't read, but can write. */ /* Need to return an EOF, so channel is closed which will send an SSL_shutdown(). */ dprintf("Got SSL_ERROR_ZERO_RETURN, this means an EOF has been reached"); bytesRead = 0; *errorCodePtr = 0; Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert"); break; case SSL_ERROR_WANT_ASYNC: /* Used with flag SSL_MODE_ASYNC, op didn't complete because an async engine is still processing data */ dprintf("Got SSL_ERROR_WANT_ASYNC, mapping this to EAGAIN"); *errorCodePtr = EAGAIN; bytesRead = -1; break; default: dprintf("Unknown error (err = %i), mapping to EOF", err); *errorCodePtr = 0; bytesRead = 0; Tls_Error(statePtr, "Unknown error"); break; } dprintf("Input(%d) -> %d [%d]", bufSize, bytesRead, *errorCodePtr); return bytesRead; } /* *----------------------------------------------------------------------------- * * TlsOutputProc -- * * This procedure is invoked by the generic I/O layer to write data to the * BIO whenever the the Tcl_Write(), Tcl_WriteChars, and Tcl_WriteObj * functions are used. Equivalent to SSL_write_ex and SSL_write. * * Results: * Returns the number of bytes written or -1 on error. Sets errorCodePtr * to a POSIX error code if an error occurred, or 0 if none. * * Side effects: * Writes output on the output device of the channel. * *----------------------------------------------------------------------------- */ static int TlsOutputProc(ClientData instanceData, const char *buf, int toWrite, int *errorCodePtr) { unsigned long backingError; State *statePtr = (State *) instanceData; int written, err; *errorCodePtr = 0; dprintf("Write(%p, %d)", (void *) statePtr, toWrite); dprintBuffer(buf, toWrite); /* Skip if user verify callback is still running */ if (statePtr->flags & TLS_TCL_CALLBACK) { dprintf("Don't process output while callbacks are running"); written = -1; *errorCodePtr = EAGAIN; return -1; } /* If not initialized, do connect */ /* Can also check SSL_is_init_finished(ssl) */ if (statePtr->flags & TLS_TCL_INIT) { int tlsConnect; dprintf("Calling Tls_WaitForConnect"); tlsConnect = Tls_WaitForConnect(statePtr, errorCodePtr, 1); if (tlsConnect < 0) { dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, *errorCodePtr); written = -1; if (*errorCodePtr == ECONNRESET) { dprintf("Got connection reset"); /* Soft EOF */ *errorCodePtr = 0; written = 0; } return written; } } if (toWrite == 0) { dprintf("zero-write"); err = BIO_flush(statePtr->bio); if (err <= 0) { dprintf("Flushing failed"); Tls_Error(statePtr, "Flush failed"); *errorCodePtr = EIO; written = 0; return -1; } written = 0; *errorCodePtr = 0; return 0; } /* * We need to clear the SSL error stack now because we sometimes reach * this function with leftover errors in the stack. If BIO_write * returns -1 and intends EAGAIN, there is a leftover error, it will be * misconstrued as an error, not EAGAIN. * * Alternatively, we may want to handle the <0 return codes from * BIO_write specially (as advised in the RSA docs). TLS's lower level * BIO functions play with the retry flags though, and this seems to * work correctly. Similar fix in TlsInputProc. - hobbs */ ERR_clear_error(); BIO_clear_retry_flags(statePtr->bio); written = BIO_write(statePtr->bio, buf, toWrite); dprintf("BIO_write(%p, %d) -> [%d]", (void *) statePtr, toWrite, written); /* Same as SSL_want, but also checks the error queue */ err = SSL_get_error(statePtr->ssl, written); backingError = ERR_get_error(); if (written <= 0) { /* The retry flag is set by the BIO_set_retry_* functions */ if (BIO_should_retry(statePtr->bio)) { dprintf("Write failed with code %d, bytes written=%d: should retry", err, written); } else { dprintf("Write failed with code %d, bytes written=%d: error condition", err, written); } /* These are the same as BIO_retry_type */ if (BIO_should_read(statePtr->bio)) { dprintf("BIO has insufficient data to read and return"); } if (BIO_should_write(statePtr->bio)) { dprintf("BIO has pending data to write"); } if (BIO_should_io_special(statePtr->bio)) { int reason = BIO_get_retry_reason(statePtr->bio); dprintf("BIO has some special condition other than read or write: code=%d", reason); } dprintf("BIO has pending data to write"); } else { BIO_flush(statePtr->bio); } switch (err) { case SSL_ERROR_NONE: /* I/O operation completed */ dprintf("SSL_ERROR_NONE"); if (written < 0) { written = 0; } break; case SSL_ERROR_SSL: /* A non-recoverable, fatal error in the SSL library occurred, usually a protocol error */ dprintf("SSL error, indicating that the connection has been aborted"); if (backingError != 0) { Tls_Error(statePtr, ERR_reason_error_string(backingError)); } else if (SSL_get_verify_result(statePtr->ssl) != X509_V_OK) { Tls_Error(statePtr, X509_verify_cert_error_string(SSL_get_verify_result(statePtr->ssl))); } else { Tls_Error(statePtr, "Unknown SSL error"); } *errorCodePtr = ECONNABORTED; written = -1; break; case SSL_ERROR_WANT_READ: /* Op did not complete due to not enough data was available. Retry later. */ dprintf("Got SSL_ERROR_WANT_READ, mapping it to EAGAIN"); *errorCodePtr = EAGAIN; written = -1; statePtr->want |= TCL_READABLE; BIO_set_retry_read(statePtr->bio); break; case SSL_ERROR_WANT_WRITE: /* Op did not complete due to unable to send all data to the BIO. Retry later. */ dprintf("Got SSL_ERROR_WANT_WRITE, mapping it to EAGAIN"); *errorCodePtr = EAGAIN; written = -1; statePtr->want |= TCL_WRITABLE; BIO_set_retry_write(statePtr->bio); break; case SSL_ERROR_WANT_X509_LOOKUP: /* Op didn't complete since callback set by SSL_CTX_set_client_cert_cb() asked to be called again */ dprintf("Got SSL_ERROR_WANT_X509_LOOKUP, mapping it to EAGAIN"); *errorCodePtr = EAGAIN; written = -1; break; case SSL_ERROR_SYSCALL: /* Some non-recoverable, fatal I/O error occurred */ dprintf("SSL_ERROR_SYSCALL"); if (backingError == 0 && written == 0) { dprintf("EOF reached") *errorCodePtr = 0; written = 0; Tls_Error(statePtr, "EOF reached"); } else if (backingError == 0 && written == -1) { dprintf("I/O error occurred (errno = %lu)", (unsigned long) Tcl_GetErrno()); *errorCodePtr = Tcl_GetErrno(); written = -1; Tls_Error(statePtr, Tcl_ErrnoMsg(*errorCodePtr)); } else { dprintf("I/O error occurred (backingError = %lu)", backingError); *errorCodePtr = Tcl_GetErrno(); written = -1; Tls_Error(statePtr, ERR_reason_error_string(backingError)); } break; case SSL_ERROR_ZERO_RETURN: /* Peer has closed the connection by sending the close_notify alert. Can't read, but can write. */ /* Need to return an EOF, so channel is closed which will send an SSL_shutdown(). */ dprintf("Got SSL_ERROR_ZERO_RETURN, this means an EOF has been reached"); *errorCodePtr = 0; written = 0; Tls_Error(statePtr, "Peer has closed the connection for writing by sending the close_notify alert"); break; case SSL_ERROR_WANT_ASYNC: /* Used with flag SSL_MODE_ASYNC, op didn't complete because an async engine is still processing data */ dprintf("Got SSL_ERROR_WANT_ASYNC, mapping this to EAGAIN"); *errorCodePtr = EAGAIN; written = -1; break; default: dprintf("unknown error: %d", err); Tls_Error(statePtr, "Unknown error"); break; } dprintf("Output(%d) -> %d", toWrite, written); return written; } /* *----------------------------------------------------------------------------- * * Tls_GetParent -- * * Get parent channel for a stacked channel. * * Results: * Tcl_Channel or NULL if none. * *----------------------------------------------------------------------------- */ Tcl_Channel Tls_GetParent(State *statePtr, int maskFlags) { dprintf("Requested to get parent of channel %p", statePtr->self); if ((statePtr->flags & ~maskFlags) & TLS_TCL_FASTPATH) { dprintf("Asked to get the parent channel while we are using FastPath -- returning NULL"); return NULL; } return Tcl_GetStackedChannel(statePtr->self); } /* *----------------------------------------------------------------------------- * * TlsSetOptionProc -- * * Sets an option to value for a SSL socket based channel. Called by the * generic I/O layer whenever the Tcl_SetChannelOption() function is used. * * Results: * TCL_OK if successful or TCL_ERROR if failed. * * Side effects: * Updates channel option to new value. * *----------------------------------------------------------------------------- */ static int TlsSetOptionProc(ClientData instanceData, /* Socket state. */ Tcl_Interp *interp, /* For errors - can be NULL. */ const char *optionName, /* Name of the option to set the value for, or * NULL to get all options and their values. */ const char *optionValue) /* Value for option. */ { State *statePtr = (State *) instanceData; Tcl_Channel parent = Tls_GetParent(statePtr, TLS_TCL_FASTPATH); Tcl_DriverSetOptionProc *setOptionProc; dprintf("Called"); /* Pass to parent */ setOptionProc = Tcl_ChannelSetOptionProc(Tcl_GetChannelType(parent)); if (setOptionProc != NULL) { return (*setOptionProc)(Tcl_GetChannelInstanceData(parent), interp, optionName, optionValue); } /* * Request for a specific option has to fail, we don't have any. */ return Tcl_BadChannelOption(interp, optionName, ""); } /* *------------------------------------------------------------------- * * TlsGetOptionProc -- * * Get a option's value for a SSL socket based channel, or a list of all * options and their values. Called by the generic I/O layer whenever the * Tcl_GetChannelOption() function is used. * * * Results: * A standard Tcl result. The value of the specified option or a list of * all options and their values is returned in the supplied DString. * * Side effects: * None. * *------------------------------------------------------------------- */ static int TlsGetOptionProc(ClientData instanceData, /* Socket state. */ Tcl_Interp *interp, /* For errors - can be NULL. */ const char *optionName, /* Name of the option to retrieve the value for, or * NULL to get all options and their values. */ Tcl_DString *optionValue) /* Where to store the computed value initialized by caller. */ { State *statePtr = (State *) instanceData; Tcl_Channel parent = Tls_GetParent(statePtr, TLS_TCL_FASTPATH); Tcl_DriverGetOptionProc *getOptionProc; dprintf("Called"); /* Pass to parent */ getOptionProc = Tcl_ChannelGetOptionProc(Tcl_GetChannelType(parent)); if (getOptionProc != NULL) { return (*getOptionProc)(Tcl_GetChannelInstanceData(parent), interp, optionName, optionValue); } else if (optionName == (char*) NULL) { /* * Request is query for all options, this is ok. */ return TCL_OK; } /* * Request for a specific option has to fail, we don't have any. */ return Tcl_BadChannelOption(interp, optionName, ""); } /* *----------------------------------------------------------------------------- * * TlsChannelHandlerTimer -- * * Called by the notifier via a timer, to flush out data waiting in * channel buffers. called by the generic I/O layer whenever the * Tcl_GetChannelHandle() function is used. * * Results: * None. * * Side effects: * Creates notification event. * *----------------------------------------------------------------------------- */ static void TlsChannelHandlerTimer(ClientData clientData) { State *statePtr = (State *) clientData; int mask = statePtr->want; /* Init to SSL_ERROR_WANT_READ and SSL_ERROR_WANT_WRITE */ dprintf("Called"); statePtr->timer = (Tcl_TimerToken) NULL; /* Check for amount of data pending in BIO write buffer */ if (BIO_wpending(statePtr->bio)) { dprintf("[chan=%p] BIO writable", statePtr->self); mask |= TCL_WRITABLE; } /* Check for amount of data pending in BIO read buffer */ if (BIO_pending(statePtr->bio)) { dprintf("[chan=%p] BIO readable", statePtr->self); mask |= TCL_READABLE; } /* Notify the generic IO layer that the mask events have occurred on the channel */ dprintf("Notifying ourselves"); Tcl_NotifyChannel(statePtr->self, mask); statePtr->want = 0; dprintf("Returning"); return; } /* *----------------------------------------------------------------------------- * * TlsWatchProc -- * * Set up the event notifier to watch for events of interest from this * channel. Called by the generic I/O layer whenever the user (or the * system) announces its (dis)interest in events on the channel. This is * called repeatedly. * * Results: * None. * * Side effects: * Sets up the time-based notifier so that future events on the channel * will be seen by TCL. * *----------------------------------------------------------------------------- */ static void TlsWatchProc(ClientData instanceData, /* The socket state. */ int mask) /* Events of interest; an OR-ed combination of * TCL_READABLE, TCL_WRITABLE and TCL_EXCEPTION. */ { Tcl_Channel parent; State *statePtr = (State *) instanceData; Tcl_DriverWatchProc *watchProc; int pending = 0; dprintf("TlsWatchProc(0x%x)", mask); dprintFlags(statePtr); /* Pretend to be dead as long as the verify callback is running. * Otherwise that callback could be invoked recursively. */ if (statePtr->flags & TLS_TCL_CALLBACK) { dprintf("Callback is on-going, doing nothing"); return; } parent = Tls_GetParent(statePtr, TLS_TCL_FASTPATH); if (statePtr->flags & TLS_TCL_HANDSHAKE_FAILED) { dprintf("Asked to watch a socket with a failed handshake -- nothing can happen here"); dprintf("Unregistering interest in the lower channel"); watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(parent)); watchProc(Tcl_GetChannelInstanceData(parent), 0); statePtr->watchMask = 0; return; } statePtr->watchMask = mask; /* No channel handlers any more. We will be notified automatically * about events on the channel below via a call to our * 'TransformNotifyProc'. But we have to pass the interest down now. * We are allowed to add additional 'interest' to the mask if we want * to. But this transformation has no such interest. It just passes * the request down, unchanged. */ dprintf("Registering our interest in the lower channel (chan=%p)", (void *) parent); watchProc = Tcl_ChannelWatchProc(Tcl_GetChannelType(parent)); watchProc(Tcl_GetChannelInstanceData(parent), mask); /* Do we have any pending events */ pending = (statePtr->want || \ ((mask & TCL_READABLE) && ((Tcl_InputBuffered(statePtr->self) > 0) || (BIO_ctrl_pending(statePtr->bio) > 0))) || ((mask & TCL_WRITABLE) && ((Tcl_OutputBuffered(statePtr->self) > 0) || (BIO_ctrl_wpending(statePtr->bio) > 0)))); dprintf("IO Want=%d, input buffer=%d, output buffer=%d, BIO pending=%zd, BIO wpending=%zd", \ statePtr->want, Tcl_InputBuffered(statePtr->self), Tcl_OutputBuffered(statePtr->self), \ BIO_ctrl_pending(statePtr->bio), BIO_ctrl_wpending(statePtr->bio)); if (!(mask & TCL_READABLE) || pending == 0) { /* Remove timer, if any */ if (statePtr->timer != (Tcl_TimerToken) NULL) { dprintf("A timer was found, deleting it"); Tcl_DeleteTimerHandler(statePtr->timer); statePtr->timer = (Tcl_TimerToken) NULL; } } else { /* Add timer, if none */ if (statePtr->timer == (Tcl_TimerToken) NULL) { dprintf("Creating a new timer since data appears to be waiting"); statePtr->timer = Tcl_CreateTimerHandler(TLS_TCL_DELAY, TlsChannelHandlerTimer, (ClientData) statePtr); } } } /* *----------------------------------------------------------------------------- * * TlsGetHandleProc -- * * This procedure is invoked by the generic IO level to retrieve an OS * specific handle associated with the channel. Not used for transforms. * * Results: * The appropriate Tcl_File handle or NULL if none. * * Side effects: * None. * *----------------------------------------------------------------------------- */ static int TlsGetHandleProc(ClientData instanceData, /* Socket state. */ int direction, /* TCL_READABLE or TCL_WRITABLE */ ClientData *handlePtr) /* Handle associated with the channel */ { State *statePtr = (State *) instanceData; return Tcl_GetChannelHandle(Tls_GetParent(statePtr, TLS_TCL_FASTPATH), direction, handlePtr); } /* *----------------------------------------------------------------------------- * * TlsNotifyProc -- * * This procedure is invoked by the generic IO level to notify the channel * that an event has occurred on the underlying channel. It is used by stacked channel drivers that * wish to be notified of events that occur on the underlying (stacked) * channel. * * Results: * Type of event or 0 if failed * * Side effects: * May process the incoming event by itself. * *----------------------------------------------------------------------------- */ static int TlsNotifyProc(ClientData instanceData, /* Socket state. */ int mask) /* type of event that occurred: * OR-ed combination of TCL_READABLE or TCL_WRITABLE */ { State *statePtr = (State *) instanceData; int errorCode = 0; dprintf("Called"); /* * Delete an existing timer. It was not fired, yet we are * here, so the channel below generated such an event and we * don't have to. The renewal of the interest after the * execution of channel handlers will eventually cause us to * recreate the timer (in WatchProc). */ if (statePtr->timer != (Tcl_TimerToken) NULL) { Tcl_DeleteTimerHandler(statePtr->timer); statePtr->timer = (Tcl_TimerToken) NULL; } /* Skip if user verify callback is still running */ if (statePtr->flags & TLS_TCL_CALLBACK) { dprintf("Callback is on-going, returning failed"); return 0; } /* If not initialized, do connect */ if (statePtr->flags & TLS_TCL_INIT) { int tlsConnect; dprintf("Calling Tls_WaitForConnect"); tlsConnect = Tls_WaitForConnect(statePtr, &errorCode, 1); if (tlsConnect < 1) { dprintf("Got an error waiting to connect (tlsConnect = %i, *errorCodePtr = %i)", tlsConnect, errorCode); if (errorCode == EAGAIN) { dprintf("Async flag could be set (didn't check) and errorCode == EAGAIN: Returning failed"); return 0; } dprintf("Tls_WaitForConnect returned an error"); } } dprintf("Returning %i", mask); /* * An event occurred in the underlying channel. This * transformation doesn't process such events thus returns the * incoming mask unchanged. */ return mask; } /* *----------------------------------------------------------------------------- * * Tls_ChannelType -- * * Defines the correct TLS channel driver handlers for this channel type. * * Results: * Tcl_ChannelType structure. * * Side effects: * None. * *----------------------------------------------------------------------------- */ static const Tcl_ChannelType tlsChannelType = { "tls", /* Type name */ TCL_CHANNEL_VERSION_5, /* v5 channel */ TlsCloseProc, /* Close proc */ TlsInputProc, /* Input proc */ TlsOutputProc, /* Output proc */ NULL, /* Seek proc */ TlsSetOptionProc, /* Set option proc */ TlsGetOptionProc, /* Get option proc */ TlsWatchProc, /* Initialize notifier */ TlsGetHandleProc, /* Get OS handles out of channel */ TlsClose2Proc, /* close2proc */ TlsBlockModeProc, /* Set blocking/nonblocking mode*/ NULL, /* Flush proc */ TlsNotifyProc, /* Handling of events bubbling up */ NULL, /* Wide seek proc */ NULL, /* Thread action */ NULL /* Truncate */ }; const Tcl_ChannelType *Tls_ChannelType(void) { return &tlsChannelType; }
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