diff --git a/output.cc b/output.cc
index 1936b6d2b..39f4a09a4 100644
--- a/output.cc
+++ b/output.cc
@@ -504,7 +504,7 @@ void printportoutput(const Target *currenths, const PortList *plist) {
   char serviceinfo[64];
   int i;
   int first = 1;
-  struct protoent *proto;
+  struct nprotoent *proto;
   Port *current;
   Port port;
   char hostname[1200];
@@ -2282,7 +2282,7 @@ static void printtraceroute_normal(const Target *currenths) {
     log_write(LOG_PLAIN, "TRACEROUTE (using port %d/%s)\n",
               probe.pd.sctp.dport, proto2ascii_lowercase(probe.proto));
   } else if (probe.type == PS_ICMP || probe.type == PS_ICMPV6 || probe.type == PS_PROTO) {
-    struct protoent *proto = nmap_getprotbynum(probe.proto);
+    struct nprotoent *proto = nmap_getprotbynum(probe.proto);
     log_write(LOG_PLAIN, "TRACEROUTE (using proto %d/%s)\n",
               probe.proto, proto ? proto->p_name : "unknown");
   } else if (probe.type == PS_NONE) {
@@ -2389,7 +2389,7 @@ static void printtraceroute_xml(const Target *currenths) {
     xml_attribute("port", "%d", probe.pd.sctp.dport);
     xml_attribute("proto", "%s", proto2ascii_lowercase(probe.proto));
   } else if (probe.type == PS_ICMP || probe.type == PS_PROTO) {
-    const struct protoent *proto = nmap_getprotbynum(probe.proto);
+    const struct nprotoent *proto = nmap_getprotbynum(probe.proto);
     if (proto == NULL)
       xml_attribute("proto", "%d", probe.proto);
     else
diff --git a/portlist.cc b/portlist.cc
index 392bdb69f..01aa8fb0c 100644
--- a/portlist.cc
+++ b/portlist.cc
@@ -141,7 +141,7 @@ void Port::getNmapServiceName(char *namebuf, int buflen) const {
   if (service != NULL && service->name != NULL) {
     service_name = service->name;
   } else {
-    const struct servent *service;
+    const struct nservent *service;
 
     service = nmap_getservbyport(portno, IPPROTO2STR(proto));
     if (service != NULL)
@@ -259,13 +259,13 @@ void PortList::getServiceDeductions(u16 portno, int protocol, struct serviceDedu
 
   port = lookupPort(portno, protocol);
   if (port == NULL || port->service == NULL) {
-    const struct servent *service;
+    const struct nservent *service;
 
     /* Look up the service name. */
     *sd = serviceDeductions();
     service = nmap_getservbyport(portno, IPPROTO2STR(protocol));
     if (service != NULL)
-      sd->name = service->s_name;
+      sd->name = strdup(service->s_name);
     else
       sd->name = NULL;
     sd->name_confidence = 3;
@@ -329,7 +329,7 @@ void PortList::setServiceProbeResults(u16 portno, int protocol,
     /* PROBESTATE_FINISHED_NOMATCH, PROBESTATE_EXCLUDED, PROBESTATE_INCOMPLETE.
        Just look up the service name if none is provided. */
     if (sname == NULL) {
-      const struct servent *service;
+      const struct nservent *service;
       service = nmap_getservbyport(portno, IPPROTO2STR(protocol));
       if (service != NULL)
         sname = service->s_name;
diff --git a/protocols.cc b/protocols.cc
index c960cda33..fd1cc89bc 100644
--- a/protocols.cc
+++ b/protocols.cc
@@ -128,7 +128,7 @@ static int nmap_protocols_init() {
     numipprots++;
 
     current = (struct protocol_list *) cp_alloc(sizeof(struct protocol_list));
-    current->protoent = (struct protoent *) cp_alloc(sizeof(struct protoent));
+    current->protoent = (struct nprotoent *) cp_alloc(sizeof(struct nprotoent));
     current->next = NULL;
     if (previous == NULL) {
       protocol_table[protno % PROTOCOL_TABLE_SIZE] = current;
@@ -137,7 +137,6 @@ static int nmap_protocols_init() {
     }
     current->protoent->p_name = cp_strdup(protocolname);
     current->protoent->p_proto = protno;
-    current->protoent->p_aliases = NULL;
   }
   fclose(fp);
   protocols_initialized = 1;
@@ -172,7 +171,7 @@ int addprotocolsfromservmask(char *mask, u8 *porttbl) {
 }
 
 
-struct protoent *nmap_getprotbynum(int num) {
+struct nprotoent *nmap_getprotbynum(int num) {
   struct protocol_list *current;
 
   if (nmap_protocols_init() == -1)
diff --git a/protocols.h b/protocols.h
index 5a516eeaa..26c6a2b5b 100644
--- a/protocols.h
+++ b/protocols.h
@@ -77,13 +77,18 @@
 
 #define PROTOCOL_TABLE_SIZE 256
 
+struct nprotoent {
+  const char *p_name;
+  short p_proto;
+};
+
 struct protocol_list {
-  struct protoent *protoent;
+  struct nprotoent *protoent;
   struct protocol_list *next;
 };
 
 int addprotocolsfromservmask(char *mask, u8 *porttbl);
-struct protoent *nmap_getprotbynum(int num);
+struct nprotoent *nmap_getprotbynum(int num);
 
 #define MAX_IPPROTOSTRLEN 4
 #define IPPROTO2STR(p)		\
diff --git a/services.cc b/services.cc
index 01f0f9bcc..57a579d68 100644
--- a/services.cc
+++ b/services.cc
@@ -89,8 +89,8 @@ struct port_spec {
   }
 };
 
-/* This is a servent augmented by a frequency ratio. */
-struct service_node : public servent {
+/* This is a nservent augmented by a frequency ratio. */
+struct service_node : public nservent {
 public:
   double ratio;
 };
@@ -228,7 +228,6 @@ static int nmap_services_init() {
     sn.s_name = cp_strdup(servicename);
     sn.s_port = portno;
     sn.s_proto = cp_strdup(proto);
-    sn.s_aliases = NULL;
     sn.ratio = ratio;
 
     service_table[ps] = sn;
@@ -289,7 +288,7 @@ int addportsfromservmask(const char *mask, u8 *porttbl, int range_type) {
 
 
 
-const struct servent *nmap_getservbyport(int port, const char *proto) {
+const struct nservent *nmap_getservbyport(int port, const char *proto) {
   std::map<port_spec, service_node>::const_iterator i;
   port_spec ps;
 
diff --git a/services.h b/services.h
index 229378541..794b0314a 100644
--- a/services.h
+++ b/services.h
@@ -74,8 +74,14 @@
 
 #define SERVICE_TABLE_SIZE 1024
 
+struct nservent {
+  const char *s_name;
+  const char *s_proto;
+  short s_port;
+};
+
 int addportsfromservmask(const char *mask, u8 *porttbl, int range_type);
-const struct servent *nmap_getservbyport(int port, const char *proto);
+const struct nservent *nmap_getservbyport(int port, const char *proto);
 void gettoppts(double level, const char *portlist, struct scan_lists * ports, const char *exclude_list = NULL);
 
 void free_services();