Avoid static buffer for protocol hdrinfo functions

libnetutil/netutil.h

@@ -441,15 +441,20 @@ char *format_ip_options(const u8* ipopt, int ipoptlen);
 #define MEDIUM_DETAIL  2
 #define HIGH_DETAIL    3
 const char *ippackethdrinfo(const u8 *packet, u32 len, int detail);
-const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int tcppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost);
-const char *udphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int udppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost);
-const char *sctphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int sctppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost);
-const char *icmphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int icmppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost);
-const char *icmp6hdrinfo (const u8 *data, unsigned int datalen, int detail,
+int icmp6packethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost);
 
 

libnetutil/packettrace.cc

@@ -608,34 +608,32 @@ const char *ippackethdrinfo(const u8 *packet, u32 len, int detail) {
     }
   }
 
+  char *p = protoinfo;
+  int remains = sizeof(protoinfo);
+  int used = 0;
   if (hdr.proto == IPPROTO_TCP) {
-    Snprintf(protoinfo, sizeof(protoinfo), "%s IP [%s]", tcphdrinfo(data, datalen, detail, frag_off, srchost, dsthost), ipinfo);
+    used = tcppackethdrinfo(data, datalen, p, remains, detail, frag_off, srchost, dsthost);
   }
   else if (hdr.proto == IPPROTO_UDP) {
-    Snprintf(protoinfo, sizeof(protoinfo), "%s IP [%s]", udphdrinfo(data, datalen, detail, frag_off, srchost, dsthost), ipinfo);
+    used = udppackethdrinfo(data, datalen, p, remains, detail, frag_off, srchost, dsthost);
   }
   else if (hdr.proto == IPPROTO_SCTP) {
-    Snprintf(protoinfo, sizeof(protoinfo), "%s IP [%s]", sctphdrinfo(data, datalen, detail, frag_off, srchost, dsthost), ipinfo);
+    used = sctppackethdrinfo(data, datalen, p, remains, detail, frag_off, srchost, dsthost);
   }
   else if (hdr.proto == IPPROTO_ICMP) {
-    Snprintf(protoinfo, sizeof(protoinfo), "%s IP [%s]", icmphdrinfo(data, datalen, detail, frag_off, srchost, dsthost), ipinfo);
+    used = icmppackethdrinfo(data, datalen, p, remains, detail, frag_off, srchost, dsthost);
   }
   else if (hdr.proto == IPPROTO_ICMPV6) {
-    Snprintf(protoinfo, sizeof(protoinfo), "%s IP [%s]", icmp6hdrinfo(data, datalen, detail, frag_off, srchost, dsthost), ipinfo);
+    used = icmp6packethdrinfo(data, datalen, p, remains, detail, frag_off, srchost, dsthost);
   }
   else {
     /* UNKNOWN PROTOCOL **********************************************************/
-    const char *hdrstr;
+    used = Snprintf(p, remains, "%s (%d) %s > %s",
-
+        nexthdrtoa(hdr.proto, 1), hdr.proto, srchost, dsthost);
-    hdrstr = nexthdrtoa(hdr.proto, 1);
-    if (hdrstr == NULL || *hdrstr == '\0') {
-      Snprintf(protoinfo, sizeof(protoinfo), "Unknown protocol (%d) %s > %s: %s",
-        hdr.proto, srchost, dsthost, ipinfo);
-    } else {
-      Snprintf(protoinfo, sizeof(protoinfo), "%s (%d) %s > %s: %s",
-        hdrstr, hdr.proto, srchost, dsthost, ipinfo);
-    }
   }
+  p += used;
+  remains -= used;
+  Snprintf(p, remains, " IP [%s]", ipinfo);
 
   return protoinfo;
 }
@@ -657,7 +655,8 @@ static const char *get_addrstr(const char *host, char strbuf[INFO_ADDRSTRLEN])
   return host;
 }
 
-const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int tcppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost)
 {
   char srcstr[INFO_ADDRSTRLEN] = "";
@@ -666,7 +665,6 @@ const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
   dsthost = get_addrstr(dsthost, dststr);
 
   /* TCP INFORMATION ***********************************************************/
-  static char protoinfo[512] = "";
   char tcpoptinfo[256] = "";
   struct tcp_hdr tcp;
 
@@ -683,18 +681,17 @@ const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
    * less than 8 bytes. This also includes empty IP packets that say they
    * contain a TCP packet. */
   if (frag_off > 8 || datalen < 8 || (frag_off % 8 != 0)) {
-    Snprintf(protoinfo, sizeof(protoinfo), "TCP %s:?? > %s:?? ?? (incomplete)",
+    return Snprintf(outbuf, outlen, "TCP %s:?? > %s:?? ?? (incomplete)",
         srchost, dsthost);
   }
   /* For all cases after this, datalen is necessarily >= 8 and frag_off is <= 8 */
-  else {
     memcpy((u8 *)&tcp + frag_off, data, MIN(datalen, sizeof(tcp) - frag_off));
     /* how much of the original packet do we have? */
     int lastbyte = datalen + frag_off;
     bool have_seq=false, have_flags_win=false, have_sum_urp=false;
 
-    char *p = protoinfo;
+    char *p = outbuf;
-    int remains = sizeof(protoinfo) - 1;
+    int remains = outlen;
     int used = 0;
     u32 tcpdataoffset = 0;
 
@@ -783,11 +780,11 @@ tcpdone:
       remains -= used;
     }
     assert(remains > 0);
-  }
+  return outlen - remains;
-  return protoinfo;
 }
 
-const char *udphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int udppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost)
 {
   char srcstr[INFO_ADDRSTRLEN] = "";
@@ -795,31 +792,30 @@ const char *udphdrinfo (const u8 *data, unsigned int datalen, int detail,
   srchost = get_addrstr(srchost, srcstr);
   dsthost = get_addrstr(dsthost, dststr);
 
-  static char protoinfo[512] = "";
   /* UDP INFORMATION ***********************************************************/
   if((frag_off || datalen < sizeof(struct udp_hdr))) {
-    Snprintf(protoinfo, sizeof(protoinfo), "UDP %s:?? > %s:?? fragment (incomplete)",
+    return Snprintf(outbuf, outlen, "UDP %s:?? > %s:?? fragment (incomplete)",
         srchost, dsthost);
-  } else {
+  }
     struct udp_hdr udp;
     memcpy(&udp, data, sizeof(udp));
 
     if (detail == LOW_DETAIL) {
-      Snprintf(protoinfo, sizeof(protoinfo), "UDP %s:%hu > %s:%hu",
+      return Snprintf(outbuf, outlen, "UDP %s:%hu > %s:%hu",
           srchost, (unsigned short) ntohs(udp.uh_sport), dsthost, (unsigned short) ntohs(udp.uh_dport));
     } else if (detail == MEDIUM_DETAIL) {
-      Snprintf(protoinfo, sizeof(protoinfo), "UDP [%s:%hu > %s:%hu csum=0x%04X]",
+      return Snprintf(outbuf, outlen, "UDP [%s:%hu > %s:%hu csum=0x%04X]",
         srchost, (unsigned short) ntohs(udp.uh_sport), dsthost, (unsigned short) ntohs(udp.uh_dport), ntohs(udp.uh_sum));
     } else if (detail == HIGH_DETAIL) {
-      Snprintf(protoinfo, sizeof(protoinfo), "UDP [%s:%hu > %s:%hu len=%hu csum=0x%04X]",
+      return Snprintf(outbuf, outlen, "UDP [%s:%hu > %s:%hu len=%hu csum=0x%04X]",
         srchost, (unsigned short) ntohs(udp.uh_sport), dsthost, (unsigned short) ntohs(udp.uh_dport),
         (unsigned short) ntohs(udp.uh_ulen), ntohs(udp.uh_sum));
     }
-  }
+    return 0;
-  return protoinfo;
 }
 
-const char *sctphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int sctppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost)
 {
   char srcstr[INFO_ADDRSTRLEN] = "";
@@ -827,45 +823,45 @@ const char *sctphdrinfo (const u8 *data, unsigned int datalen, int detail,
   srchost = get_addrstr(srchost, srcstr);
   dsthost = get_addrstr(dsthost, dststr);
 
-  static char protoinfo[512] = "";
   /* SCTP INFORMATION **********************************************************/
   if ((frag_off || datalen < sizeof(struct sctp_hdr))) {
-    Snprintf(protoinfo, sizeof(protoinfo), "SCTP %s:?? > %s:?? fragment (incomplete)",
+    return Snprintf(outbuf, outlen, "SCTP %s:?? > %s:?? fragment (incomplete)",
         srchost, dsthost);
-  } else {
+  }
     struct sctp_hdr sctp;
     memcpy(&sctp, data, sizeof(sctp));
 
     if (detail == LOW_DETAIL) {
-      Snprintf(protoinfo, sizeof(protoinfo), "SCTP %s:%hu > %s:%hu",
+      return Snprintf(outbuf, outlen, "SCTP %s:%hu > %s:%hu",
         srchost, (unsigned short) ntohs(sctp.sh_sport), dsthost, (unsigned short) ntohs(sctp.sh_dport));
     } else if (detail == MEDIUM_DETAIL) {
-      Snprintf(protoinfo, sizeof(protoinfo), "SCTP [%s:%hu > %s:%hu csum=0x%08x]",
+      return Snprintf(outbuf, outlen, "SCTP [%s:%hu > %s:%hu csum=0x%08x]",
         srchost, (unsigned short) ntohs(sctp.sh_sport), dsthost, (unsigned short) ntohs(sctp.sh_dport), ntohl(sctp.sh_sum));
     } else if (detail == HIGH_DETAIL) {
-      Snprintf(protoinfo, sizeof(protoinfo), "SCTP [%s:%hu > %s:%hu vtag=%lu csum=0x%08x]",
+      return Snprintf(outbuf, outlen, "SCTP [%s:%hu > %s:%hu vtag=%lu csum=0x%08x]",
         srchost, (unsigned short) ntohs(sctp.sh_sport), dsthost, (unsigned short) ntohs(sctp.sh_dport),
         (unsigned long) ntohl(sctp.sh_vtag), ntohl(sctp.sh_sum));
     }
-  }
+    return 0;
-  return protoinfo;
 }
 
-const char *icmphdrinfo (const u8 *data, unsigned int datalen, int detail,
+int icmppackethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost)
 {
   if (srchost == NULL)
     srchost = "??";
   if (dsthost == NULL)
     dsthost = "??";
-  static char protoinfo[512] = "";
+
   char icmptype[128] = "";              /* Temp info about ICMP type & code  */
   char icmpfields[256] = "";            /* Temp info for various ICMP fields */
   /* ICMP INFORMATION **********************************************************/
   if((frag_off || datalen < sizeof(struct icmp_hdr))) {
-    Snprintf(protoinfo, sizeof(protoinfo), "ICMP %s > %s fragment (incomplete)",
+    return Snprintf(outbuf, outlen, "ICMP %s > %s fragment (incomplete)",
         srchost, dsthost);
-  } else {
+  }
+
   struct ip_hdr ip2;       /* Points to the IP datagram carried by some ICMP messages */
   char *ip2dst;         /* Dest IP in caried IP datagram                   */
   char auxbuff[128];    /* Aux buffer                                      */
@@ -1142,43 +1138,41 @@ const char *icmphdrinfo (const u8 *data, unsigned int datalen, int detail,
 icmpbad:
     if (icmptype[0] != '\0') {
       /* We still have this information */
-        Snprintf(protoinfo, sizeof(protoinfo), "ICMP %s > %s %s (type=%d/code=%d)",
+      return Snprintf(outbuf, outlen, "ICMP %s > %s %s (type=%d/code=%d)",
           srchost, dsthost, icmptype, icmp.icmp_type, icmp.icmp_code);
     } else {
-        Snprintf(protoinfo, sizeof(protoinfo), "ICMP %s > %s [??]",
+      return Snprintf(outbuf, outlen, "ICMP %s > %s [??]",
           srchost, dsthost);
     }
   } else {
     char icmpinfo[512] = "";              /* Temp info about ICMP.             */
     sprintf(icmpinfo,"type=%d/code=%d", icmp.icmp_type, icmp.icmp_code);
 
-      Snprintf(protoinfo, sizeof(protoinfo), "ICMP [%s > %s %s (%s) %s]",
+    return Snprintf(outbuf, outlen, "ICMP [%s > %s %s (%s) %s]",
         srchost, dsthost, icmptype, icmpinfo, icmpfields);
   }
 }
-  return protoinfo;
-}
 
-const char *icmp6hdrinfo (const u8 *data, unsigned int datalen, int detail,
+int icmp6packethdrinfo (const u8 *data, unsigned int datalen,
+    char *outbuf, int outlen, int detail,
     int frag_off, const char *srchost, const char *dsthost)
 {
   if (srchost == NULL)
     srchost = "??";
   if (dsthost == NULL)
     dsthost = "??";
-  static char protoinfo[512] = "";
+
   if (frag_off || datalen < sizeof(struct icmpv6_hdr)) {
-    Snprintf(protoinfo, sizeof(protoinfo), "ICMPv6 %s > %s (type=?/code=?)",
+    return Snprintf(outbuf, outlen, "ICMPv6 %s > %s (type=?/code=?)",
         srchost, dsthost);
   }
   else {
     const struct icmpv6_hdr *icmpv6;
 
     icmpv6 = (struct icmpv6_hdr *) data;
-    Snprintf(protoinfo, sizeof(protoinfo), "ICMPv6 %s > %s (type=%d/code=%d)",
+    return Snprintf(outbuf, outlen, "ICMPv6 %s > %s (type=%d/code=%d)",
         srchost, dsthost,
         icmpv6->icmpv6_type, icmpv6->icmpv6_code);
   }
-  return protoinfo;
 }
 

nping/utils_net.cc

@@ -904,37 +904,27 @@ int arppackethdrinfo(const u8 *packet, u32 len, u8 *dstbuff, u32 dstlen){
 } /* End of arppackethdrinfo() */
 
 
-
 int tcppackethdrinfo(const u8 *packet, size_t len, u8 *dstbuff, size_t dstlen,
      int detail, const char *src, const char *dst){
  assert(packet);
  assert(dstbuff);
 
-  const char *protoinfo = tcphdrinfo(packet, len, detail, 0, src, dst);
+ return (tcppackethdrinfo(packet, len, (char *)dstbuff, dstlen,
-  Strncpy((char*)dstbuff, protoinfo, dstlen);
+      detail, 0, src, dst) > 0 ? OP_SUCCESS : OP_FAILURE);
-
-  return OP_SUCCESS;
-
 } /* End of tcppackethdrinfo() */
 
 
-
-
 int udppackethdrinfo(const u8 *packet, size_t len, u8 *dstbuff, size_t dstlen,
     int detail, const char *src, const char *dst){
 
  assert(packet);
  assert(dstbuff);
 
-  const char *protoinfo = udphdrinfo(packet, len, detail, 0, src, dst);
+ return (udppackethdrinfo(packet, len, (char *)dstbuff, dstlen,
-  strncpy((char*)dstbuff, protoinfo, dstlen);
+      detail, 0, src, dst) > 0 ? OP_SUCCESS : OP_FAILURE);
-
-  return OP_SUCCESS;
-
 } /* End of udppackethdrinfo() */
 
 
-
 /** Returns a random (null-terminated) ASCII string with no special
   * meaning. Returned string may be between 1 and 512 bytes and contain
   * random letters and some whitespace.