--- /dev/null
+/*
+ * This program is RSPAMD agent for use with
+ * exim (http://www.exim.org) MTA by its local_scan feature.
+ *
+ * To enable exim local scan please copy this file to exim source tree
+ * Local/local_scan.c, edit Local/Makefile to add
+ *
+ * LOCAL_SCAN_SOURCE=Local/local_scan.c
+ * LOCAL_SCAN_HAS_OPTIONS=yes
+ *
+ * and compile exim.
+ *
+ * For exim compilation with local scan feature details please visit
+ * http://www.exim.org/exim-html-current/doc/html/spec_html/ch42.html
+ *
+ * For RSPAMD details please visit
+ * https://bitbucket.org/vstakhov/rspamd/
+ *
+ * Example configuration:
+ * **********************
+ *
+ * local_scan_timeout = 50s
+ *
+ * begin local_scan
+ * rspam_ip = 127.0.0.1
+ * rspam_port = 11333
+ * rspam_skip_sasl_authenticated = true
+ * # don't reject message if on of recipients from this list
+ * rspam_skip_rcpt = postmaster@example.com : some_user@example.com
+ * rspam_message = "Spam rejected; If this is not spam, please contact <postmaster@example.com>"
+ *
+ *
+ * $Id: local_scan.c 646 2010-08-11 11:49:36Z ayuzhaninov $
+ */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/uio.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <errno.h>
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "local_scan.h"
+
+#define REQUEST_LINES 64
+#define REPLY_BUF_SIZE 16384
+#define HEADER_STATUS "X-Rspam-Status"
+#define HEADER_METRIC "X-Rspam-Metric"
+#define HEADER_SCORE "X-Rspam-Score"
+
+/* configuration options */
+static uschar *daemon_ip = US"127.0.0.1";
+static int max_scan_size = 4 * 1024 * 1024;
+static uschar *reject_message = US"Spam message rejected";
+static int daemon_port = 11333;
+static BOOL skip_authenticated = TRUE;
+static uschar *want_spam_rcpt_list = US"";
+
+/* the entries must appear in alphabetical order */
+optionlist local_scan_options[] = {
+ { "rspam_ip", opt_stringptr, &daemon_ip },
+ { "rspam_max_scan_size", opt_mkint, &max_scan_size },
+ { "rspam_message", opt_stringptr, &reject_message },
+ { "rspam_port", opt_int, &daemon_port },
+ { "rspam_skip_rcpt", opt_stringptr, &want_spam_rcpt_list },
+ { "rspam_skip_sasl_authenticated", opt_bool, &skip_authenticated },
+};
+
+int local_scan_options_count = sizeof(local_scan_options) / sizeof(optionlist);
+
+/* push formatted line into vector */
+int push_line(struct iovec *iov, int i, const char *fmt, ...);
+
+int
+local_scan(int fd, uschar **return_text)
+{
+ struct stat sb;
+ struct sockaddr_in server_in;
+ int s, i, r, request_p = 0, headers_count = 0, is_spam = 0, is_reject = 0;
+ off_t message_size;
+ struct iovec request_v[REQUEST_LINES], *headers_v;
+#if "@CMAKE_SYSTEM_NAME@" == "FreeBSD"
+ struct sf_hdtr headers_sf;
+#endif
+ uschar *helo, *log_buf;
+ header_line *header_p;
+ char reply_buf[REPLY_BUF_SIZE], io_buf[BUFSIZ];
+ ssize_t size;
+ char *tok_ptr, *str;
+ char mteric[128], result[8];
+ float score, required_score;
+
+ *return_text = reject_message;
+
+ /*
+ * one msaage can be send via exim+rspamd twice
+ * remove header from previous pass
+ */
+ header_remove(0, US HEADER_STATUS);
+ header_remove(0, US HEADER_METRIC);
+
+ /* check message size */
+ fstat(fd,&sb); /* XXX shuld check error */
+ message_size = sb.st_size - SPOOL_DATA_START_OFFSET;
+ if (message_size > max_scan_size) {
+ header_add(' ', HEADER_STATUS ": skip_big\n");
+ log_write (0, LOG_MAIN, "rspam: message larger than rspam_max_scan_size, accept");
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+ /* don't scan mail from authenticated hosts */
+ if (skip_authenticated && sender_host_authenticated != NULL) {
+ header_add(' ', HEADER_STATUS ": skip_authenticated\n");
+ log_write(0, LOG_MAIN, "rspam: from=<%s> ip=%s authenticated (%s), skip check\n",
+ sender_address,
+ sender_host_address == NULL ? US"localhost" : sender_host_address,
+ sender_host_authenticated);
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+ /*
+ * add status header, which mean, that message was not scanned
+ * if message will be scanned, this header will be replaced
+ */
+ header_add(' ', HEADER_STATUS ": check_error\n");
+
+ /* create socket */
+ memset(&server_in, 0, sizeof(server_in));
+ server_in.sin_family = AF_INET;
+ server_in.sin_port = htons(daemon_port);
+ server_in.sin_addr.s_addr = inet_addr(daemon_ip);
+ if ((s = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
+ log_write(0, LOG_MAIN, "rspam: socket (%d: %s)", errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+ if (connect(s, (struct sockaddr *) &server_in, sizeof(server_in)) < 0) {
+ close(s);
+ log_write(0, LOG_MAIN, "rspam: can't connect to %s:%d (%d: %s)", daemon_ip, daemon_port, errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+ /* count message headers */
+ for (header_p = header_list; header_p != NULL; header_p = header_p->next) {
+ /* header type '*' is used for replaced or deleted header */
+ if (header_p->type == '*')
+ continue;
+ headers_count++;
+ }
+
+ /* write message headers to vector */
+#if "@CMAKE_SYSTEM_NAME@" == "FreeBSD"
+ memset(&headers_sf, 0, sizeof(headers_sf));
+ if (headers_count > 0) {
+ headers_v = store_get((headers_count + 1)* sizeof(*headers_v));
+ i = 0;
+ for (header_p = header_list; header_p != NULL; header_p = header_p->next) {
+ if (header_p->type == '*')
+ continue;
+ headers_v[i].iov_base = header_p->text;
+ headers_v[i].iov_len = header_p->slen;
+ i++;
+ message_size += header_p->slen;
+ }
+ headers_v[i].iov_base = "\n";
+ headers_v[i].iov_len = strlen("\n");
+ message_size += strlen("\n");
+
+ headers_sf.headers = headers_v;
+ headers_sf.hdr_cnt = headers_count + 1;
+ }
+#else
+ if (headers_count > 0) {
+ headers_v = store_get((headers_count + 1)* sizeof(*headers_v));
+ i = 0;
+ for (header_p = header_list; header_p != NULL; header_p = header_p->next) {
+ if (header_p->type == '*')
+ continue;
+ headers_v[i].iov_base = header_p->text;
+ headers_v[i].iov_len = header_p->slen;
+ i++;
+ message_size += header_p->slen;
+ }
+ headers_v[i].iov_base = "\n";
+ headers_v[i].iov_len = strlen("\n");
+ message_size += strlen("\n");
+#endif
+
+ /* write request to vector */
+ r = 0;
+ r += push_line(request_v, request_p++, "SYMBOLS RSPAMC/1.1\r\n");
+ r += push_line(request_v, request_p++, "Content-length: " OFF_T_FMT "\r\n", message_size);
+ r += push_line(request_v, request_p++, "Queue-Id: %s\r\n", message_id);
+ r += push_line(request_v, request_p++, "From: %s\r\n", sender_address);
+ r += push_line(request_v, request_p++, "Recipient-Number: %d\r\n", recipients_count);
+ for (i = 0; i < recipients_count; i ++)
+ r += push_line(request_v, request_p++, "Rcpt: %s\r\n", recipients_list[i].address);
+ if ((helo = expand_string(US"$sender_helo_name")) != NULL && *helo != '\0')
+ r += push_line(request_v, request_p++, "Helo: %s\r\n", helo);
+ if (sender_host_address != NULL)
+ r += push_line(request_v, request_p++, "IP: %s\r\n", sender_host_address);
+ r += push_line(request_v, request_p++, "\r\n");
+
+ if (r < 0) {
+ close(s);
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+ /* send request */
+ if (writev(s, request_v, request_p) < 0) {
+ close(s);
+ log_write(0, LOG_MAIN, "rspam: can't send request to %s:%d (%d: %s)", daemon_ip, daemon_port, errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+#if "@CMAKE_SYSTEM_NAME@" == "FreeBSD"
+ /* send headers (from iovec) and message body (from file) */
+ if (sendfile(fd, s, SPOOL_DATA_START_OFFSET, 0, &headers_sf, NULL, 0) < 0) {
+ close(s);
+ log_write(0, LOG_MAIN, "rspam: can't send message to %s:%d (%d: %s)", daemon_ip, daemon_port, errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+#else
+ /* send headers */
+ if (writev(s, headers_v, headers_count) < 0) {
+ close(s);
+ log_write(0, LOG_MAIN, "rspam: can't send headers to %s:%d (%d: %s)", daemon_ip, daemon_port, errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+ /* Send message */
+ while ((r = read (fd, io_buf, sizeof (io_buf))) > 0) {
+ if (write (s, io_buf, r) < 0) {
+ close(s);
+ log_write(0, LOG_MAIN, "rspam: can't send message to %s:%d (%d: %s)", daemon_ip, daemon_port, errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+ }
+#endif
+
+ /* read reply from rspamd */
+ reply_buf[0] = '\0';
+ size = 0;
+ while ((r = read(s, reply_buf + size, sizeof(reply_buf) - size - 1)) > 0 && size < sizeof(reply_buf) - 1) {
+ size += r;
+ }
+
+ if (r < 0) {
+ close(s);
+ log_write(0, LOG_MAIN, "rspam: can't read from %s:%d (%d: %s)", daemon_ip, daemon_port, errno, strerror(errno));
+ return LOCAL_SCAN_ACCEPT;
+ }
+ reply_buf[size] = '\0';
+ close(s);
+
+ if (size >= REPLY_BUF_SIZE - 1) {
+ log_write(0, LOG_MAIN, "rspam: buffer is full, reply may be truncated");
+ }
+
+ /* parse reply */
+ tok_ptr = reply_buf;
+
+ /*
+ * rspamd can use several metrics, logic implimented here:
+ * if any metric more than reject_score - will reject
+ * if any metric true - message will be marked as spam
+ */
+
+ /* First line is: <PROTOCOL>/<VERSION> <ERROR_CODE> <ERROR_REPLY> */
+ str = strsep(&tok_ptr, "\r\n");
+ if (str != NULL && sscanf(str, "%*s %d %*s", &i) == 1) {
+ if (i != 0) {
+ log_write(0, LOG_MAIN, "rspam: server error: %s", str);
+ return LOCAL_SCAN_ACCEPT;
+ }
+ } else {
+ log_write(0, LOG_MAIN, "rspam: bad reply from server: %s", str);
+ return LOCAL_SCAN_ACCEPT;
+ }
+
+ while ((str = strsep(&tok_ptr, "\r\n")) != NULL) {
+ /* skip empty tockens */
+ if (*str == '\0')
+ continue;
+ if (strncmp(str, "Metric:", strlen("Metric:")) == 0) {
+ /*
+ * parse line like
+ * Metric: default; False; 27.00 / 30.00
+ */
+ if (sscanf(str, "Metric: %s %s %f / %f",
+ mteric, result, &score, &required_score) == 4) {
+ log_write(0, LOG_MAIN, "rspam: metric %s %s %.2f / %.2f",
+ mteric, result, score, required_score);
+ header_add(' ', HEADER_METRIC ": %s %s %.2f / %.2f\n",
+ mteric, result, score, required_score);
+ /* integers score for use in sieve ascii-numeric comparator */
+ if (strcmp(mteric, "default;") == 0)
+ header_add(' ', HEADER_SCORE ": %d\n",
+ (int)round(score));
+ } else {
+ log_write(0, LOG_MAIN, "rspam: can't parse: %s", str);
+ return LOCAL_SCAN_ACCEPT;
+ }
+ } else if (strncmp(str, "Action:", strlen("Action:")) == 0) {
+ /* line like Action: add header */
+ str += strlen("Action: ");
+ if (strncmp(str, "reject", strlen("reject")) == 0) {
+ is_reject = 1;
+ is_spam = 1;
+ } else if (strncmp(str, "add header", strlen("add header")) == 0) {
+ is_spam = 1;
+ }
+ }
+ }
+
+ /* XXX many allocs by string_sprintf()
+ * better to sprintf() to single buffer allocated by store_get()
+ */
+ log_buf = string_sprintf("message to");
+ for (i = 0; i < recipients_count; i ++) {
+ log_buf = string_sprintf("%s %s", log_buf, recipients_list[i].address);
+ if (is_reject && lss_match_address(recipients_list[i].address, want_spam_rcpt_list, TRUE) == OK) {
+ is_reject = 0;
+ log_write(0, LOG_MAIN, "rspam: %s want spam, don't reject this message", recipients_list[i].address);
+ }
+ }
+
+ if (is_reject) {
+ log_write(0, LOG_MAIN, "rspam: reject %s", log_buf);
+ return LOCAL_SCAN_REJECT;
+ }
+
+ header_remove(0, US HEADER_STATUS);
+ if (is_spam) {
+ header_add(' ', HEADER_STATUS ": spam\n");
+ log_write(0, LOG_MAIN, "rspam: message marked as spam");
+ } else {
+ header_add(' ', HEADER_STATUS ": ham\n");
+ log_write(0, LOG_MAIN, "rspam: message marked as ham");
+ }
+
+ return LOCAL_SCAN_ACCEPT;
+}
+
+int
+push_line(struct iovec *iov, const int i, const char *fmt, ...)
+{
+ va_list ap;
+ size_t len;
+ char buf[512];
+
+ if (i >= REQUEST_LINES) {
+ log_write(0, LOG_MAIN, "rspam: %s: index out of bounds", __FUNCTION__);
+ return (-1);
+ }
+
+ va_start(ap, fmt);
+ len = vsnprintf(buf, sizeof(buf), fmt, ap);
+ va_end(ap);
+
+ iov[i].iov_base = string_copy(US buf);
+ iov[i].iov_len = len;
+
+ if (len >= sizeof(buf)) {
+ log_write(0, LOG_MAIN, "rspam: %s: error, string was longer than %d", __FUNCTION__, sizeof(buf));
+ return (-1);
+ }
+
+ return 0;
+}
+
projects / thirdparty / rspamd.git / commitdiff
