diff options
| -rw-r--r-- | ares/ares_getnameinfo.c | 102 |
1 files changed, 47 insertions, 55 deletions
diff --git a/ares/ares_getnameinfo.c b/ares/ares_getnameinfo.c index 23ca0cbee..d13b11d47 100644 --- a/ares/ares_getnameinfo.c +++ b/ares/ares_getnameinfo.c @@ -70,7 +70,8 @@ struct nameinfo_query { #endif static void nameinfo_callback(void *arg, int status, struct hostent *host); -static char *lookup_service(unsigned short port, int flags, char *buf); +static char *lookup_service(unsigned short port, int flags, + char *buf, size_t buflen); #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID static void append_scopeid(struct sockaddr_in6 *addr6, unsigned int scopeid, char *buf, size_t buflen); @@ -109,7 +110,7 @@ void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa, socklen_t port = addr->sin_port; else port = addr6->sin6_port; - service = lookup_service(port, flags, buf); + service = lookup_service(port, flags, buf, sizeof(buf)); callback(arg, ARES_SUCCESS, NULL, service); return; } @@ -122,7 +123,7 @@ void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa, socklen_t { unsigned int port = 0; char ipbuf[IPBUFSIZ]; - char srvbuf[32]; + char srvbuf[33]; char *service = NULL; ipbuf[0] = 0; @@ -150,7 +151,7 @@ void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa, socklen_t } /* They also want a service */ if (flags & ARES_NI_LOOKUPSERVICE) - service = lookup_service(port, flags, srvbuf); + service = lookup_service(port, flags, srvbuf, sizeof(srvbuf)); callback(arg, ARES_SUCCESS, ipbuf, service); return; } @@ -198,10 +199,10 @@ static void nameinfo_callback(void *arg, int status, struct hostent *host) { if (niquery->family == AF_INET) service = lookup_service(niquery->addr.addr4.sin_port, - niquery->flags, srvbuf); + niquery->flags, srvbuf, sizeof(srvbuf)); else service = lookup_service(niquery->addr.addr6.sin6_port, - niquery->flags, srvbuf); + niquery->flags, srvbuf, sizeof(srvbuf)); } /* NOFQDN means we have to strip off the domain name portion. We do this by determining our own domain name, then searching the string @@ -240,10 +241,10 @@ static void nameinfo_callback(void *arg, int status, struct hostent *host) { if (niquery->family == AF_INET) service = lookup_service(niquery->addr.addr4.sin_port, - niquery->flags, srvbuf); + niquery->flags, srvbuf, sizeof(srvbuf)); else service = lookup_service(niquery->addr.addr6.sin6_port, - niquery->flags, srvbuf); + niquery->flags, srvbuf, sizeof(srvbuf)); } niquery->callback(niquery->arg, ARES_SUCCESS, ipbuf, service); return; @@ -253,31 +254,21 @@ static void nameinfo_callback(void *arg, int status, struct hostent *host) } static char *lookup_service(unsigned short port, int flags, - char *buf) /* 33 bytes buffer */ + char *buf, size_t buflen) { + const char *proto; + struct servent *sep; +#ifdef HAVE_GETSERVBYPORT_R + struct servent se; +#endif + char tmpbuf[4096]; + if (port) - { - /* Just return the port as a string */ + { if (flags & ARES_NI_NUMERICSERV) - sprintf(buf, "%u", ntohs(port)); + sep = NULL; else - { - struct servent *se; - const char *proto; -#ifdef HAVE_GETSERVBYPORT_R -#if GETSERVBYPORT_R_ARGS == 6 - struct servent ret; - char buf[4096]; - int len = 4096; -#elif GETSERVBYPORT_R_ARGS == 5 - struct servent ret; - char buf[4096]; - int len = 4096; -#elif GETSERVBYPORT_R_ARGS == 4 - struct servent ret; - struct servent_data sed; -#endif -#endif /* HAVE_GETSERVBYPORT_R */ + { if (flags & ARES_NI_UDP) proto = "udp"; else if (flags & ARES_NI_SCTP) @@ -287,39 +278,40 @@ static char *lookup_service(unsigned short port, int flags, else proto = "tcp"; #ifdef HAVE_GETSERVBYPORT_R + sep = &se; + memset(tmpbuf, 0, sizeof(tmpbuf)); #if GETSERVBYPORT_R_ARGS == 6 - se = &ret; - if (getservbyport_r(port, proto, se, buf, len, &ret)) - se = NULL; + if (getservbyport_r(port, proto, &se, (void *)tmpbuf, sizeof(tmpbuf), &sep) != 0) + sep = NULL; #elif GETSERVBYPORT_R_ARGS == 5 - se = &ret; - se = getservbyport_r(port, proto, se, buf, len); + sep = getservbyport_r(port, proto, &se, (void *)tmpbuf, sizeof(tmpbuf)); #elif GETSERVBYPORT_R_ARGS == 4 - se = &ret; - if (getservbyport_r(port, proto, se, &sed) == -1) - se = NULL; -#else + if (getservbyport_r(port, proto, &se, (void *)tmpbuf) != 0) + sep = NULL; +#else /* Lets just hope the OS uses TLS! */ - se = getservbyport(port, proto); -#endif -#else + sep = getservbyport(port, proto); +#endif +#else /* Lets just hope the OS uses TLS! */ - se = getservbyport(port, proto); -#endif - if (se && se->s_name) { - size_t len = strlen(se->s_name); - if(len < 33) { - strcpy(buf, se->s_name); - } - else - /* too big name to fit the buffer */ - buf[0]=0; - } - else - sprintf(buf, "%u", ntohs(port)); - } + sep = getservbyport(port, proto); +#endif + } + if (sep && sep->s_name) + /* get service name */ + strcpy(tmpbuf, sep->s_name); + else + /* get port as a string */ + sprintf(tmpbuf, "%u", ntohs(port)); + if (strlen(tmpbuf) < buflen) + /* return it if buffer big enough */ + strcpy(buf, tmpbuf); + else + /* avoid reusing previous one */ + buf[0] = '\0'; return buf; } + buf[0] = '\0'; return NULL; } |