Hi Huichao,
> According to RFC791,the options may appear or not in datagrams.
> They must be implemented by all IP modules (host and gateways).
> What is optional is their transmission in any particular datagram,
> not their implementation.So we have to deal with it during the
> fragmenting process.Add some test data for the IPv4 header optional
> field fragmenting.
>
...
> diff --git a/lib/ip_frag/rte_ipv4_fragmentation.c
> b/lib/ip_frag/rte_ipv4_fragmentation.c
> index 2e7739d..82c070b 100644
> --- a/lib/ip_frag/rte_ipv4_fragmentation.c
> +++ b/lib/ip_frag/rte_ipv4_fragmentation.c
> @@ -12,6 +12,12 @@
>
> #include "ip_frag_common.h"
>
> +/* IP options */
> +#define RTE_IPOPT_EOL 0
> +#define RTE_IPOPT_NOP 1
> +#define RTE_IPOPT_COPIED(v) ((v) & 0x80)
> +#define RTE_IPOPT_MAX_LEN 40
> +
> /* Fragment Offset */
> #define RTE_IPV4_HDR_DF_SHIFT 14
> #define RTE_IPV4_HDR_MF_SHIFT 13
> @@ -22,6 +28,8 @@
>
> #define IPV4_HDR_FO_ALIGN (1 <<
> RTE_IPV4_HDR_FO_SHIFT)
>
> +#define RTE_IPV4_HDR_MAX_LEN 60
> +
> static inline void __fill_ipv4hdr_frag(struct rte_ipv4_hdr *dst,
> const struct rte_ipv4_hdr *src, uint16_t header_len,
> uint16_t len, uint16_t fofs, uint16_t dofs, uint32_t mf)
> @@ -41,6 +49,58 @@ static inline void __free_fragments(struct rte_mbuf *mb[],
> uint32_t num)
> rte_pktmbuf_free(mb[i]);
> }
>
> +static inline void __create_ipopt_frag_hdr(uint8_t *iph,
> + uint16_t *ipopt_len, uint8_t *ipopt_frag_hdr)
> +{
> + uint16_t len = *ipopt_len;
> + struct rte_ipv4_hdr *iph_opt = (struct rte_ipv4_hdr *)ipopt_frag_hdr;
> +
> + *ipopt_len = 0;
> + rte_memcpy(ipopt_frag_hdr, iph, sizeof(struct rte_ipv4_hdr));
> + iph_opt->ihl = sizeof(struct rte_ipv4_hdr) / RTE_IPV4_IHL_MULTIPLIER;
> + ipopt_frag_hdr += sizeof(struct rte_ipv4_hdr);
> +
> + if (unlikely(len > RTE_IPOPT_MAX_LEN))
> + return;
> +
> + uint8_t *p_opt = iph + sizeof(struct rte_ipv4_hdr);
> +
> + while (len > 0) {
> + if (unlikely(*p_opt == RTE_IPOPT_NOP)) {
> + len--;
> + p_opt++;
> +#ifdef RTE_IPOPT_KEEP_IP_HLEN
Who will define this macro and when?
In general we trying to avoid conditional compilations within DPDK.
Can we always use one way or another?
As you are doing a copy anyway, probably no harm just
completely remove RTE_IPOPT_KEEP_IP_HLEN and related behaviour
and copy only options that need to be copied.
WDYT?
> + ipopt_frag_hdr[(*ipopt_len)++] = RTE_IPOPT_NOP;
> +#endif
> + continue;
> + } else if (unlikely(*p_opt == RTE_IPOPT_EOL))
> + break;
> +
> + if (p_opt[1] < 2 || p_opt[1] > len)
> + break;
> + if (RTE_IPOPT_COPIED(*p_opt)) {
> + rte_memcpy(ipopt_frag_hdr + *ipopt_len,
> + p_opt, p_opt[1]);
> + *ipopt_len += p_opt[1];
> +#ifdef RTE_IPOPT_KEEP_IP_HLEN
> + } else {
> + memset(ipopt_frag_hdr + *ipopt_len,
> + RTE_IPOPT_NOP, p_opt[1]);
> + *ipopt_len += p_opt[1];
> +#endif
> + }
> +
> + len -= p_opt[1];
> + p_opt += p_opt[1];
> + }
> +
> + len = RTE_ALIGN_CEIL(*ipopt_len, RTE_IPV4_IHL_MULTIPLIER);
> + memset(ipopt_frag_hdr + *ipopt_len,
> + RTE_IPOPT_EOL, len - *ipopt_len);
> + *ipopt_len = len;
> + iph_opt->ihl += len / RTE_IPV4_IHL_MULTIPLIER;
> +}
> +
> /**
> * IPv4 fragmentation.
> *
> @@ -76,6 +136,8 @@ static inline void __free_fragments(struct rte_mbuf *mb[],
> uint32_t num)
> uint32_t more_in_segs;
> uint16_t fragment_offset, flag_offset, frag_size, header_len;
> uint16_t frag_bytes_remaining;
> + uint8_t ipopt_frag_hdr[RTE_IPV4_HDR_MAX_LEN];
> + uint16_t ipopt_len;
>
> /*
> * Formal parameter checking.
> @@ -117,6 +179,7 @@ static inline void __free_fragments(struct rte_mbuf
> *mb[], uint32_t num)
> in_seg_data_pos = header_len;
> out_pkt_pos = 0;
> fragment_offset = 0;
> + ipopt_len = header_len - sizeof(struct rte_ipv4_hdr);
>
> more_in_segs = 1;
> while (likely(more_in_segs)) {
> @@ -188,10 +251,26 @@ static inline void __free_fragments(struct rte_mbuf
> *mb[], uint32_t num)
> (uint16_t)out_pkt->pkt_len,
> flag_offset, fragment_offset, more_in_segs);
>
> - fragment_offset = (uint16_t)(fragment_offset +
> - out_pkt->pkt_len - header_len);
> + /* Create a separate IP header to handle frag options. */
> + if (unlikely((fragment_offset == 0) &&
> + ((flag_offset & RTE_IPV4_HDR_OFFSET_MASK) == 0) &&
> + (ipopt_len))) {
> + __create_ipopt_frag_hdr((uint8_t *)in_hdr,
> + &ipopt_len, ipopt_frag_hdr);
> +
> + fragment_offset = (uint16_t)(fragment_offset +
> + out_pkt->pkt_len - header_len);
>
> - out_pkt->l3_len = header_len;
> + out_pkt->l3_len = header_len;
> +
> + header_len = sizeof(struct rte_ipv4_hdr) + ipopt_len;
> + in_hdr = (struct rte_ipv4_hdr *)ipopt_frag_hdr;
> + } else {
> + fragment_offset = (uint16_t)(fragment_offset +
> + out_pkt->pkt_len - header_len);
> +
> + out_pkt->l3_len = header_len;
> + }
>
> /* Write the fragment to the output list */
> pkts_out[out_pkt_pos] = out_pkt;
> --
> 1.8.3.1
