From: Konstantin Ananyev Date: Mon, 5 Nov 2018 12:18:58 +0000 (+0000) Subject: ip_frag: use key length for key comparison X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=b8d5dfd4a5f006794d85f93fc97134460ffbdfdf;p=dpdk.git ip_frag: use key length for key comparison Right now reassembly code relies on src_dst[] being all zeroes to determine is it free/occupied entry in the fragments table. This is suboptimal and error prone - user can crash DPDK ip_reassembly app by something like the following scapy script: x=Ether(src=...,dst=...)/IP(dst='0.0.0.0',src='0.0.0.0',id=0)/('X'*1000) frags=fragment(x, fragsize=500) sendp(frags, iface=...) To overcome that issue and reduce overhead of 'key invalidate' and 'key is empty' operations - add key_len into keys comparision procedure. Fixes: 4f1a8f633862 ("ip_frag: add IPv6 reassembly") Cc: stable@dpdk.org Reported-by: Ryan E Hall Reported-by: Alexander V Gutkin Signed-off-by: Konstantin Ananyev --- diff --git a/lib/librte_ip_frag/ip_frag_common.h b/lib/librte_ip_frag/ip_frag_common.h index 0f62e2e163..a17a74076c 100644 --- a/lib/librte_ip_frag/ip_frag_common.h +++ b/lib/librte_ip_frag/ip_frag_common.h @@ -58,20 +58,14 @@ struct rte_mbuf *ipv6_frag_reassemble(struct ip_frag_pkt *fp); static inline int ip_frag_key_is_empty(const struct ip_frag_key * key) { - uint32_t i; - for (i = 0; i < RTE_MIN(key->key_len, RTE_DIM(key->src_dst)); i++) - if (key->src_dst[i] != 0) - return 0; - return 1; + return (key->key_len == 0); } -/* empty the key */ +/* invalidate the key */ static inline void ip_frag_key_invalidate(struct ip_frag_key * key) { - uint32_t i; - for (i = 0; i < key->key_len; i++) - key->src_dst[i] = 0; + key->key_len = 0; } /* compare two keys */ @@ -80,7 +74,7 @@ ip_frag_key_cmp(const struct ip_frag_key * k1, const struct ip_frag_key * k2) { uint32_t i; uint64_t val; - val = k1->id ^ k2->id; + val = k1->id_key_len ^ k2->id_key_len; for (i = 0; i < k1->key_len; i++) val |= k1->src_dst[i] ^ k2->src_dst[i]; return val; diff --git a/lib/librte_ip_frag/rte_ip_frag.h b/lib/librte_ip_frag/rte_ip_frag.h index 7f425f6100..a4ccaf9d14 100644 --- a/lib/librte_ip_frag/rte_ip_frag.h +++ b/lib/librte_ip_frag/rte_ip_frag.h @@ -44,9 +44,17 @@ struct ip_frag { /** @internal to uniquely identify fragmented datagram. */ struct ip_frag_key { - uint64_t src_dst[4]; /**< src address, first 8 bytes used for IPv4 */ - uint32_t id; /**< dst address */ - uint32_t key_len; /**< src/dst key length */ + uint64_t src_dst[4]; + /**< src and dst address, only first 8 bytes used for IPv4 */ + RTE_STD_C11 + union { + uint64_t id_key_len; /**< combined for easy fetch */ + __extension__ + struct { + uint32_t id; /**< packet id */ + uint32_t key_len; /**< src/dst key length */ + }; + }; }; /**