1 files changed, 116 insertions, 0 deletions
diff --git a/src/common/services.c b/src/common/services.c
new file mode 100644
index 0000000..fc981bc
--- /dev/null
+++ b/src/common/services.c
@@ -0,0 +1,116 @@
+/* $Id: services.c 2423 2010-03-13 07:09:49Z aturner $ */
+
+/*
+ * Copyright (c) 2004-2010 Aaron Turner.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright owners nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "defines.h"
+#include "common.h"
+
+#include <sys/types.h>
+#include <regex.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+
+/**
+ * parses /etc/services so we know which ports are service ports
+ */
+void
+parse_services(const char *file, tcpr_services_t *services)
+{
+    FILE *service = NULL;
+    char service_line[MAXLINE], port[10], proto[10];
+    regex_t preg;
+    u_int16_t portc;
+    size_t nmatch = 3;
+    regmatch_t pmatch[3];
+    char regex[] = "([0-9]+)/(tcp|udp)"; /* matches the port as pmatch[1], service pmatch[2] */
+
+    dbgx(1, "Parsing %s", file);
+    memset(service_line, '\0', MAXLINE);
+
+    /* mark all ports not a service */
+    memset(services->tcp, '\0', NUM_PORTS);
+    memset(services->udp, '\0', NUM_PORTS);
+
+    if ((service = fopen(file, "r")) == NULL) {
+        errx(-1, "Unable to open service file: %s\n%s", file, strerror(errno));
+    }
+    
+    /* compile our regexes */
+    if ((regcomp(&preg, regex, REG_ICASE|REG_EXTENDED)) != 0) {
+        errx(-1, "Unable to compile regex: %s", regex);
+    }
+
+    /* parse the entire file */
+    while ((fgets(service_line, MAXLINE, service)) != NULL) {
+        /* zero out our vars */
+        memset(port, '\0', 10);
+        memset(proto, '\0', 10);
+        portc = 0;
+        
+        dbgx(4, "Procesing: %s", service_line);
+        
+        /* look for format of 1234/tcp */
+        if ((regexec(&preg, service_line, nmatch, pmatch, 0)) == 0) { /* matches */
+            if (nmatch < 2) {
+                err(-1, "WTF?  I matched the line, but I don't know where!");
+            }
+
+            /* strip out the port & proto from the line */
+            strncpy(port, &service_line[pmatch[1].rm_so], (pmatch[1].rm_eo - pmatch[1].rm_so));
+            strncpy(proto, &service_line[pmatch[2].rm_so], (pmatch[2].rm_eo - pmatch[2].rm_so));
+
+            /* convert port[] into an integer */
+            portc = (u_int16_t)atoi(port);
+
+            /* update appropriate service array with the server port */
+            if (strcmp(proto, "tcp") == 0) {
+                dbgx(3, "Setting TCP/%d as a server port", portc);
+                services->tcp[portc] = 1; /* mark it as a service port */
+            } else if (strcmp(proto, "udp") == 0) {
+                dbgx(3, "Setting UDP/%d as a server port", portc);
+                services->udp[portc] = 1;
+            } else {
+                warnx("Skipping unknown protocol service %s/%d", proto, portc);
+            }
+        }
+    }
+}
+
+/*
+ Local Variables:
+ mode:c
+ indent-tabs-mode:nil
+ c-basic-offset:4
+ End:
+*/
+