Function pg_GSS_write

src/interfaces/libpq/fe-secure-gssapi.c:92–258

* Attempt to write len bytes of data from ptr to a GSSAPI-encrypted connection. * * The connection must be already set up for GSSAPI encryption (i.e., GSSAPI * transport negotiation is complete). * * On success, returns the number of data bytes consumed (possibly less than * len). On failure, returns -1 with errno set appropriately. If the errno * indicates a non-retryable error, a messag

 * once the socket is ready.
 */
ssize_t
pg_GSS_write(PGconn *conn, const void *ptr, size_t len)
{
	OM_uint32	major,
				minor;
	gss_buffer_desc input,
				output = GSS_C_EMPTY_BUFFER;
	ssize_t		ret = -1;
	size_t		bytes_sent = 0;
	size_t		bytes_to_encrypt;
	size_t		bytes_encrypted;
	gss_ctx_id_t gctx = conn->gctx;

	/*
	 * When we get a failure, we must not tell the caller we have successfully
	 * transmitted everything, else it won't retry.  Hence a "success"
	 * (positive) return value must only count source bytes corresponding to
	 * fully-transmitted encrypted packets.  The amount of source data
	 * corresponding to the current partly-transmitted packet is remembered in
	 * PqGSSSendConsumed.  On a retry, the caller *must* be sending that data
	 * again, so if it offers a len less than that, something is wrong.
	 */
	if (len < PqGSSSendConsumed)
	{
		appendPQExpBufferStr(&conn->errorMessage,
							 "GSSAPI caller failed to retransmit all data needing to be retried\n");
		errno = EINVAL;
		return -1;
	}

	/* Discount whatever source data we already encrypted. */
	bytes_to_encrypt = len - PqGSSSendConsumed;
	bytes_encrypted = PqGSSSendConsumed;

	/*
	 * Loop through encrypting data and sending it out until it's all done or
	 * pqsecure_raw_write() complains (which would likely mean that the socket
	 * is non-blocking and the requested send() would block, or there was some
	 * kind of actual error).
	 */
	while (bytes_to_encrypt || PqGSSSendLength)
	{
		int			conf_state = 0;
		uint32		netlen;

		/*
		 * Check if we have data in the encrypted output buffer that needs to
		 * be sent (possibly left over from a previous call), and if so, try
		 * to send it.  If we aren't able to, return that fact back up to the
		 * caller.
		 */
		if (PqGSSSendLength)
		{
			ssize_t		ret;
			ssize_t		amount = PqGSSSendLength - PqGSSSendNext;

			ret = pqsecure_raw_write(conn, PqGSSSendBuffer + PqGSSSendNext, amount);
			if (ret <= 0)