diff options
| -rw-r--r-- | ares/ares_getnameinfo.c | 32 |
1 files changed, 21 insertions, 11 deletions
diff --git a/ares/ares_getnameinfo.c b/ares/ares_getnameinfo.c index 0dbed732b..35e611f47 100644 --- a/ares/ares_getnameinfo.c +++ b/ares/ares_getnameinfo.c @@ -72,7 +72,8 @@ struct nameinfo_query { static void nameinfo_callback(void *arg, int status, struct hostent *host); static char *lookup_service(unsigned short port, int flags, char *buf); #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID -static char *append_scopeid(struct sockaddr_in6 *addr6, unsigned int scopeid, char *buf); +static void append_scopeid(struct sockaddr_in6 *addr6, unsigned int scopeid, + char *buf, size_t buflen); #endif static char *ares_striendstr(const char *s1, const char *s2); @@ -139,7 +140,7 @@ void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa, socklen_t port = addr6->sin6_port; /* If the system supports scope IDs, use it */ #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID - append_scopeid(addr6, flags, ipbuf); + append_scopeid(addr6, flags, ipbuf, sizeof(ipbuf)); #endif } else @@ -231,7 +232,7 @@ static void nameinfo_callback(void *arg, int status, struct hostent *host) { ares_inet_ntop(AF_INET6, &niquery->addr.addr6.sin6_addr, ipbuf, IPBUFSIZ); #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID - append_scopeid(&niquery->addr.addr6, niquery->flags, ipbuf); + append_scopeid(&niquery->addr.addr6, niquery->flags, ipbuf, sizeof(ipbuf)); #endif } /* They want a service too */ @@ -321,30 +322,39 @@ static char *lookup_service(unsigned short port, int flags, } #ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID -static char *append_scopeid(struct sockaddr_in6 *addr6, unsigned int flags, - char *buf) +static void append_scopeid(struct sockaddr_in6 *addr6, unsigned int flags, + char *buf, size_t buflen) { - char tmpbuf[IF_NAMESIZE + 1]; + char fmt_u[] = "%u"; + char fmt_lu[] = "%lu"; + char tmpbuf[IF_NAMESIZE + 2]; + size_t bufl; + char *fmt = (sizeof(addr6->sin6_scope_id) > sizeof(unsigned int))?fmt_lu:fmt_u; tmpbuf[0] = '%'; + #ifdef HAVE_IF_INDEXTONAME if ((flags & ARES_NI_NUMERICSCOPE) || (!IN6_IS_ADDR_LINKLOCAL(&addr6->sin6_addr) && !IN6_IS_ADDR_MC_LINKLOCAL(&addr6->sin6_addr))) { - sprintf(&tmpbuf[1], "%u", addr6->sin6_scope_id); + sprintf(&tmpbuf[1], fmt, addr6->sin6_scope_id); } else { if (if_indextoname(addr6->sin6_scope_id, &tmpbuf[1]) == NULL) - sprintf(&tmpbuf[1], "%u", addr6->sin6_scope_id); + sprintf(&tmpbuf[1], fmt, addr6->sin6_scope_id); } #else - sprintf(&tmpbuf[1], "%u", addr6->sin6_scope_id); + sprintf(&tmpbuf[1], fmt, addr6->sin6_scope_id); (void) flags; #endif - strcat(buf, tmpbuf); - return buf; + tmpbuf[IF_NAMESIZE + 1] = '\0'; + bufl = strlen(buf); + + if(bufl + strlen(tmpbuf) < buflen) + /* only append the scopeid string if it fits in the target buffer */ + strcpy(&buf[bufl], tmpbuf); } #endif |