diff options
| author | andre <andre@FreeBSD.org> | 2005-08-21 15:09:07 +0000 |
|---|---|---|
| committer | andre <andre@FreeBSD.org> | 2005-08-21 15:09:07 +0000 |
| commit | 11e9c09778f14d8940ca3e370836b6bb52af63de (patch) | |
| tree | d666bfcdd8518e198cf7e0dbf28cdd3927115253 /sys | |
| parent | ba9d3582e31d21e3e6ca4cfc9b138aa3868fb080 (diff) | |
| download | FreeBSD-src-11e9c09778f14d8940ca3e370836b6bb52af63de.zip FreeBSD-src-11e9c09778f14d8940ca3e370836b6bb52af63de.tar.gz | |
Add a sysctl to change to length of the quotation of the original
packet in an ICMP reply. The minimum of 8 bytes is internally
enforced. The maximum quotation is the remaining space in the
reply mbuf.
This option is added in response to the issues raised in I-D
draft-gont-icmp-payload-00.txt.
MFC after: 2 weeks
Spnsored by: TCP/IP Optimizations Fundraise 2005
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/netinet/ip_icmp.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/sys/netinet/ip_icmp.c b/sys/netinet/ip_icmp.c index 0cba594..265562e 100644 --- a/sys/netinet/ip_icmp.c +++ b/sys/netinet/ip_icmp.c @@ -115,6 +115,11 @@ SYSCTL_INT(_net_inet_icmp, OID_AUTO, reply_from_interface, CTLFLAG_RW, &icmp_rfi, 0, "ICMP reply from incoming interface for " "non-local packets"); +static int icmp_quotelen = 8; +SYSCTL_INT(_net_inet_icmp, OID_AUTO, quotelen, CTLFLAG_RW, + &icmp_quotelen, 0, "Number of bytes from original packet to " + "quote in ICMP reply"); + /* * ICMP broadcast echo sysctl */ @@ -184,7 +189,13 @@ icmp_error(n, type, code, dest, mtu) #ifdef MAC mac_create_mbuf_netlayer(n, m); #endif - icmplen = min(oiplen + 8, oip->ip_len); + /* + * Calculate length to quote from original packet and + * prevent the ICMP mbuf from overflowing. + */ + icmplen = min(oiplen + max(8, icmp_quote), oip->ip_len); + icmplen = min(icmplen, M_TRAILINGSPACE(m) - + (ICMP_MINLEN + sizeof(struct ip))); if (icmplen < sizeof(struct ip)) panic("icmp_error: bad length"); m->m_len = icmplen + ICMP_MINLEN; |
