[Rework] Initial milter protocol support

src/libserver/CMakeLists.txt

@@ -10,6 +10,7 @@ SET(LIBRSPAMDSERVERSRC
 				${CMAKE_CURRENT_SOURCE_DIR}/fuzzy_backend.c
 				${CMAKE_CURRENT_SOURCE_DIR}/fuzzy_backend_sqlite.c
 				${CMAKE_CURRENT_SOURCE_DIR}/html.c
+				${CMAKE_CURRENT_SOURCE_DIR}/milter.c
 				${CMAKE_CURRENT_SOURCE_DIR}/monitored.c
 				${CMAKE_CURRENT_SOURCE_DIR}/protocol.c
 				${CMAKE_CURRENT_SOURCE_DIR}/re_cache.c

src/libserver/milter.c

@@ -0,0 +1,217 @@
+/*-
+ * Copyright 2017 Vsevolod Stakhov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "config.h"
+#include "milter.h"
+#include "milter_internal.h"
+#include "email_addr.h"
+#include "addr.h"
+#include "unix-std.h"
+
+static gboolean  rspamd_milter_handle_session (
+		struct rspamd_milter_session *session,
+		struct rspamd_milter_private *priv);
+
+static GQuark
+rspamd_milter_quark (void)
+{
+	return g_quark_from_static_string ("milter");
+}
+
+static void
+rspamd_milter_io_handler (gint fd, gshort what, void *ud)
+{
+	struct rspamd_milter_session *session = ud;
+	struct rspamd_milter_private *priv;
+
+	priv = session->priv;
+}
+
+static inline void
+rspamd_milter_plan_io (struct rspamd_milter_session *session,
+		struct rspamd_milter_private *priv, gshort what)
+{
+	if (event_get_base (&priv->ev)) {
+		event_del (&priv->ev);
+	}
+
+	event_set (&priv->ev, priv->fd, what, rspamd_milter_io_handler,
+			session);
+	event_base_set (priv->ev_base, &priv->ev);
+	event_add (&priv->ev, priv->ptv);
+}
+
+static gboolean
+rspamd_milter_consume_input (struct rspamd_milter_session *session,
+		struct rspamd_milter_private *priv)
+{
+	const guchar *p, *end;
+
+	p = priv->parser.buf->str + priv->parser.pos;
+	end = priv->parser.buf->str + priv->parser.buf->len;
+
+	while (p < end) {
+		switch (priv->parser.state) {
+		case st_read_cmd:
+			priv->parser.cur_cmd = *p;
+			priv->parser.state = st_len_1;
+			priv->parser.datalen = 0;
+			p++;
+			break;
+		case st_len_1:
+			/* The first length byte in big endian order */
+			priv->parser.datalen |= *p << 24;
+			priv->parser.state = st_len_2;
+			p++;
+			break;
+		case st_len_2:
+			/* The second length byte in big endian order */
+			priv->parser.datalen |= *p << 16;
+			priv->parser.state = st_len_3;
+			p++;
+			break;
+		case st_len_3:
+			/* The third length byte in big endian order */
+			priv->parser.datalen |= *p << 8;
+			priv->parser.state = st_len_4;
+			p++;
+			break;
+		case st_len_4:
+			/* The fourth length byte in big endian order */
+			priv->parser.datalen |= *p;
+			priv->parser.state = st_read_data;
+			p++;
+			break;
+		case st_read_data:
+			/* We might need some more data in buffer for further steps */
+			break;
+		}
+	}
+}
+
+static gboolean
+rspamd_milter_handle_session (struct rspamd_milter_session *session,
+		struct rspamd_milter_private *priv)
+{
+	gssize r;
+	GError *err;
+
+	g_assert (session != NULL);
+
+	switch (priv->state) {
+	case RSPAMD_MILTER_READ_MORE:
+		if (priv->parser.pos >= priv->parser.buf->allocated) {
+			priv->parser.buf = rspamd_fstring_grow (priv->parser.buf,
+					priv->parser.pos * 2);
+		}
+
+		r = read (priv->fd, priv->parser.buf->str + priv->parser.pos,
+				priv->parser.buf->allocated - priv->parser.pos);
+
+		if (r == -1) {
+			if (errno == EAGAIN || errno == EINTR) {
+				rspamd_milter_plan_io (session, priv, EV_READ);
+			}
+			else {
+				/* Fatal IO error */
+				err = g_error_new (rspamd_milter_quark (), errno,
+						"IO error: %s", strerror (errno));
+				REF_RETAIN (session);
+				priv->err_cb (priv->fd, session, priv->ud, err);
+				REF_RELEASE (session);
+				g_error_free (err);
+			}
+		}
+		else if (r == 0) {
+			err = g_error_new (rspamd_milter_quark (), ECONNRESET,
+					"Unexpected EOF");
+			REF_RETAIN (session);
+			priv->err_cb (priv->fd, session, priv->ud, err);
+			REF_RELEASE (session);
+			g_error_free (err);
+		}
+		else {
+			priv->parser.buf->len += r;
+
+			return rspamd_milter_consume_input (session, priv);
+		}
+	}
+}
+
+
+gboolean
+rspamd_milter_handle_socket (gint fd, const struct timeval *tv,
+		struct event_base *ev_base, rspamd_milter_finish finish_cb,
+		rspamd_milter_error error_cb, void *ud)
+{
+	struct rspamd_milter_session *session;
+	struct rspamd_milter_private *priv;
+
+	g_assert (finish_cb != NULL);
+	g_assert (error_cb != NULL);
+
+	session = g_malloc0 (sizeof (*session));
+	priv = g_malloc0 (sizeof (*priv));
+	priv->fd = fd;
+	priv->ud = ud;
+	priv->fin_cb = finish_cb;
+	priv->err_cb = error_cb;
+	priv->parser.state = st_read_cmd;
+	priv->parser.buf = rspamd_fstring_sized_new (100);
+	priv->ev_base = ev_base;
+	priv->state = RSPAMD_MILTER_READ_MORE;
+
+	if (tv) {
+		memcpy (&priv->tv, tv, sizeof (*tv));
+		priv->ptv = &priv->tv;
+	}
+	else {
+		priv->ptv = NULL;
+	}
+
+	session->priv = priv;
+
+	return rspamd_milter_handle_session (session, priv);
+}
+
+gboolean rspamd_milter_set_reply (struct rspamd_milter_session *session,
+		rspamd_fstring_t *xcode,
+		rspamd_fstring_t *rcode,
+		rspamd_fstring_t *reply);
+
+gboolean rspamd_milter_send_action (gint fd,
+		struct rspamd_milter_session *session,
+		enum rspamd_milter_reply act);
+
+gboolean rspamd_milter_add_header (struct rspamd_milter_session *session,
+		GString *name, GString *value);
+
+gboolean rspamd_milter_del_header (struct rspamd_milter_session *session,
+		GString *name);
+
+void
+rspamd_milter_session_unref (struct rspamd_milter_session *session)
+{
+	REF_RELEASE (session);
+}
+
+struct rspamd_milter_session *
+rspamd_milter_session_ref (struct rspamd_milter_session *session)
+{
+	REF_RETAIN (session);
+
+	return session;
+}

src/libserver/milter.h

@@ -0,0 +1,118 @@
+/*-
+ * Copyright 2017 Vsevolod Stakhov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef RSPAMD_MILTER_H
+#define RSPAMD_MILTER_H
+
+#include "config.h"
+#include "fstring.h"
+#include "addr.h"
+#include "ref.h"
+
+enum rspamd_milter_reply {
+	RSPAMD_MILTER_ADDRCPT = '+',
+	RSPAMD_MILTER_DELRCPT = '-',
+	RSPAMD_MILTER_ACCEPT = 'a',
+	RSPAMD_MILTER_CONTINUE = 'c',
+	RSPAMD_MILTER_DISCARD = 'd',
+	RSPAMD_MILTER_ADDHEADER = 'h',
+	RSPAMD_MILTER_CHGHEADER = 'm',
+	RSPAMD_MILTER_REJECT = 'r',
+	RSPAMD_MILTER_TEMPFAIL = 't',
+	RSPAMD_MILTER_REPLYCODE = 'y'
+};
+
+struct rspamd_email_address;
+struct event_base;
+
+struct rspamd_milter_session {
+	GHashTable *macros;
+	rspamd_inet_addr_t *addr;
+	struct rspamd_email_address *from;
+	GPtrArray *rcpts;
+	rspamd_fstring_t *helo;
+	rspamd_fstring_t *hostname;
+	rspamd_fstring_t *message;
+	void *priv;
+	ref_entry_t ref;
+};
+
+typedef void (*rspamd_milter_finish) (gint fd,
+		struct rspamd_milter_session *session, void *ud);
+typedef void (*rspamd_milter_error) (gint fd,
+		struct rspamd_milter_session *session,
+		void *ud, GError *err);
+
+/**
+ * Handles socket with milter protocol
+ * @param fd
+ * @param finish_cb
+ * @param error_cb
+ * @param ud
+ * @return
+ */
+gboolean rspamd_milter_handle_socket (gint fd, const struct timeval *tv,
+		struct event_base *ev_base, rspamd_milter_finish finish_cb,
+		rspamd_milter_error error_cb, void *ud);
+
+/**
+ * Sets SMTP reply string
+ * @param session
+ * @param xcode
+ * @param rcode
+ * @param reply
+ * @return
+ */
+gboolean rspamd_milter_set_reply (struct rspamd_milter_session *session,
+		rspamd_fstring_t *xcode,
+		rspamd_fstring_t *rcode,
+		rspamd_fstring_t *reply);
+
+/**
+ * Send some action to the MTA
+ * @param fd
+ * @param session
+ * @param act
+ * @return
+ */
+gboolean rspamd_milter_send_action (gint fd,
+		struct rspamd_milter_session *session,
+		enum rspamd_milter_reply act);
+
+/**
+ * Adds some header
+ * @param session
+ * @param name
+ * @param value
+ * @return
+ */
+gboolean rspamd_milter_add_header (struct rspamd_milter_session *session,
+		GString *name, GString *value);
+
+/**
+ * Removes some header
+ * @param session
+ * @param name
+ * @return
+ */
+gboolean rspamd_milter_del_header (struct rspamd_milter_session *session,
+		GString *name);
+
+void rspamd_milter_session_unref (struct rspamd_milter_session *session);
+
+struct rspamd_milter_session * rspamd_milter_session_ref (
+		struct rspamd_milter_session *session);
+
+#endif

src/libserver/milter_internal.h

@@ -0,0 +1,67 @@
+/*-
+ * Copyright 2017 Vsevolod Stakhov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef RSPAMD_MILTER_INTERNAL_H
+#define RSPAMD_MILTER_INTERNAL_H
+
+#include "config.h"
+#include <event.h>
+
+enum rspamd_milter_state {
+	st_read_cmd,
+	st_len_1,
+	st_len_2,
+	st_len_3,
+	st_len_4,
+	st_read_data
+};
+
+struct rspamd_milter_parser {
+	rspamd_fstring_t *buf;
+	goffset pos;
+	gsize datalen;
+	enum rspamd_milter_state state;
+	gchar cur_cmd;
+};
+
+struct rspamd_milter_outbuf {
+	rspamd_fstring_t *buf;
+	goffset pos;
+	struct rspamd_milter_outbuf *next, *prev;
+};
+
+enum rspamd_milter_io_state {
+	RSPAMD_MILTER_READ_MORE,
+	RSPAMD_MILTER_PROCESS_DATA,
+	RSPAMD_MILTER_WRITE_REPLY,
+	RSPAMD_MILTER_WANNA_DIE
+};
+
+struct rspamd_milter_private {
+	struct rspamd_milter_parser parser;
+	struct rspamd_milter_outbuf *out_chain;
+	struct event ev;
+	struct timeval tv;
+	struct timeval *ptv;
+	struct event_base *ev_base;
+	rspamd_milter_finish fin_cb;
+	rspamd_milter_error err_cb;
+	void *ud;
+	enum rspamd_milter_io_state state;
+	int fd;
+};
+
+#endif