cne_ip.h

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/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright (c) 1982, 1986, 1990, 1993
 *      The Regents of the University of California.
 * Copyright (c) 2019-2022 Intel Corporation.
 * Copyright (c) 2014 6WIND S.A.
 * All rights reserved.
 */
 
#ifndef _CNE_IP_H_
#define _CNE_IP_H_
 
#include <stdint.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netinet/ip.h>
 
#include <cne_byteorder.h>
#include <pktmbuf.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
struct cne_ipv4_hdr {
    uint8_t version_ihl;        
    uint8_t type_of_service;    
    cne_be16_t total_length;    
    cne_be16_t packet_id;       
    cne_be16_t fragment_offset; 
    uint8_t time_to_live;       
    uint8_t next_proto_id;      
    cne_be16_t hdr_checksum;    
    cne_be32_t src_addr;        
    cne_be32_t dst_addr;        
} __cne_packed;
 
#define CNE_IPV4(a, b, c, d) \
    ((uint32_t)(((a)&0xff) << 24) | (((b)&0xff) << 16) | (((c)&0xff) << 8) | ((d)&0xff))
 
#define CNE_IPV4_MAX_PKT_LEN 65535
 
#define CNE_IPV4_HDR_IHL_MASK (0x0f)
#define CNE_IPV4_IHL_MULTIPLIER (4)
 
/* Type of Service fields */
#define CNE_IPV4_HDR_DSCP_MASK (0xfc)
#define CNE_IPV4_HDR_ECN_MASK  (0x03)
#define CNE_IPV4_HDR_ECN_CE    CNE_IPV4_HDR_ECN_MASK
 
/* Fragment Offset * Flags. */
#define CNE_IPV4_HDR_DF_SHIFT 14
#define CNE_IPV4_HDR_MF_SHIFT 13
#define CNE_IPV4_HDR_FO_SHIFT 3
 
#define CNE_IPV4_HDR_DF_FLAG (1 << CNE_IPV4_HDR_DF_SHIFT)
#define CNE_IPV4_HDR_MF_FLAG (1 << CNE_IPV4_HDR_MF_SHIFT)
 
#define CNE_IPV4_HDR_OFFSET_MASK ((1 << CNE_IPV4_HDR_MF_SHIFT) - 1)
 
#define CNE_IPV4_HDR_OFFSET_UNITS 8
 
/*
 * IPv4 address types
 */
#define CNE_IPV4_ANY             ((uint32_t)0x00000000) 
#define CNE_IPV4_LOOPBACK        ((uint32_t)0x7f000001) 
#define CNE_IPV4_BROADCAST       ((uint32_t)0xe0000000) 
#define CNE_IPV4_ALLHOSTS_GROUP  ((uint32_t)0xe0000001) 
#define CNE_IPV4_ALLRTRS_GROUP   ((uint32_t)0xe0000002) 
#define CNE_IPV4_MAX_LOCAL_GROUP ((uint32_t)0xe00000ff) 
/*
 * IPv4 Multicast-related macros
 */
#define CNE_IPV4_MIN_MCAST CNE_IPV4(224, 0, 0, 0) 
#define CNE_IPV4_MAX_MCAST                                           \
    CNE_IPV4(239, 255, 255, 255) 
#define CNE_IS_IPV4_MCAST(x) ((x) >= CNE_IPV4_MIN_MCAST && (x) <= CNE_IPV4_MAX_MCAST)
/* IPv4 default fields values */
#define CNE_IPV4_MIN_IHL (0x5)
#define CNE_IPV4_VHL_DEF ((IPVERSION << 4) | CNE_IPV4_MIN_IHL)
 
static inline uint8_t
cne_ipv4_hdr_len(const struct cne_ipv4_hdr *ipv4_hdr)
{
    return (uint8_t)((ipv4_hdr->version_ihl & CNE_IPV4_HDR_IHL_MASK) * CNE_IPV4_IHL_MULTIPLIER);
}
 
static inline uint32_t
__cne_raw_cksum(const void *buf, size_t len, uint32_t sum)
{
    /* workaround gcc strict-aliasing warning */
    uintptr_t ptr = (uintptr_t)buf;
    typedef uint16_t __attribute__((__may_alias__)) u16_p;
    const u16_p *u16_buf = (const u16_p *)ptr;
 
    while (len >= (sizeof(*u16_buf) * 4)) {
        sum += u16_buf[0];
        sum += u16_buf[1];
        sum += u16_buf[2];
        sum += u16_buf[3];
        len -= sizeof(*u16_buf) * 4;
        u16_buf += 4;
    }
    while (len >= sizeof(*u16_buf)) {
        sum += *u16_buf;
        len -= sizeof(*u16_buf);
        u16_buf += 1;
    }
 
    /* if length is in odd bytes */
    if (len == 1) {
        uint16_t left     = 0;
        *(uint8_t *)&left = *(const uint8_t *)u16_buf;
        sum += left;
    }
 
    return sum;
}
 
static inline uint16_t
__cne_raw_cksum_reduce(uint32_t sum)
{
    sum = ((sum & 0xffff0000) >> 16) + (sum & 0xffff);
    sum = ((sum & 0xffff0000) >> 16) + (sum & 0xffff);
    return (uint16_t)sum;
}
 
static inline uint16_t
cne_raw_cksum(const void *buf, size_t len)
{
    uint32_t sum;
 
    sum = __cne_raw_cksum(buf, len, 0);
    return __cne_raw_cksum_reduce(sum);
}
 
static inline uint16_t
cne_raw_cksum_mbuf(const pktmbuf_t *m, uint32_t off, uint32_t len)
{
    return cne_raw_cksum(pktmbuf_mtod_offset(m, const char *, off), len);
}
 
static inline uint16_t
cne_ipv4_cksum(const struct cne_ipv4_hdr *ipv4_hdr)
{
    uint16_t cksum;
    cksum = cne_raw_cksum(ipv4_hdr, cne_ipv4_hdr_len(ipv4_hdr));
    return (uint16_t)~cksum;
}
 
static inline uint16_t
cne_ipv4_phdr_cksum(const struct cne_ipv4_hdr *ipv4_hdr, uint64_t ol_flags)
{
    struct ipv4_psd_header {
        uint32_t src_addr; /* IP address of source host. */
        uint32_t dst_addr; /* IP address of destination host. */
        uint8_t zero;      /* zero. */
        uint8_t proto;     /* L4 protocol type. */
        uint16_t len;      /* L4 length. */
    } psd_hdr;
    uint32_t l3_len;
 
    psd_hdr.src_addr = ipv4_hdr->src_addr;
    psd_hdr.dst_addr = ipv4_hdr->dst_addr;
    psd_hdr.zero     = 0;
    psd_hdr.proto    = ipv4_hdr->next_proto_id;
 
    if (ol_flags & CNE_MBUF_F_TX_TCP_SEG)
        psd_hdr.len = 0;
    else {
        l3_len      = be16toh(ipv4_hdr->total_length);
        psd_hdr.len = htobe16((uint16_t)(l3_len - cne_ipv4_hdr_len(ipv4_hdr)));
    }
 
    return cne_raw_cksum(&psd_hdr, sizeof(psd_hdr));
}
 
static inline uint16_t
__ipv4_udptcp_cksum(const struct cne_ipv4_hdr *ipv4_hdr, const void *l4_hdr)
{
    uint32_t cksum;
    uint32_t l3_len, l4_len;
    uint8_t ip_hdr_len;
 
    ip_hdr_len = cne_ipv4_hdr_len(ipv4_hdr);
    l3_len     = be16toh(ipv4_hdr->total_length);
    if (l3_len < ip_hdr_len)
        return 0;
 
    l4_len = l3_len - ip_hdr_len;
 
    cksum = cne_raw_cksum(l4_hdr, l4_len);
    cksum += cne_ipv4_phdr_cksum(ipv4_hdr, 0);
 
    cksum = ((cksum & 0xffff0000) >> 16) + (cksum & 0xffff);
 
    return (uint16_t)cksum;
}
 
static inline uint16_t
cne_ipv4_udptcp_cksum(const struct cne_ipv4_hdr *ipv4_hdr, const void *l4_hdr)
{
    uint16_t cksum = __ipv4_udptcp_cksum(ipv4_hdr, l4_hdr);
 
    cksum = ~cksum;
    /*
     * Per RFC 768:If the computed checksum is zero for UDP,
     * it is transmitted as all ones
     * (the equivalent in one's complement arithmetic).
     */
    if (cksum == 0 && ipv4_hdr->next_proto_id == IPPROTO_UDP)
        cksum = 0xffff;
 
    return cksum;
}
 
static inline int
cne_ipv4_udptcp_cksum_verify(const struct cne_ipv4_hdr *ipv4_hdr, const void *l4_hdr)
{
    uint16_t cksum = __ipv4_udptcp_cksum(ipv4_hdr, l4_hdr);
 
    if (cksum != 0xffff)
        return -1;
 
    return 0;
}
 
struct cne_ipv6_hdr {
    cne_be32_t vtc_flow;    
    cne_be16_t payload_len; 
    uint8_t proto;          
    uint8_t hop_limits;     
    uint8_t src_addr[16];   
    uint8_t dst_addr[16];   
} __cne_packed;
 
/* IPv6 vtc_flow: IPv / TC / flow_label */
#define CNE_IPV6_HDR_FL_SHIFT  0
#define CNE_IPV6_HDR_TC_SHIFT  20
#define CNE_IPV6_HDR_FL_MASK   ((1u << CNE_IPV6_HDR_TC_SHIFT) - 1)
#define CNE_IPV6_HDR_TC_MASK   (0xff << CNE_IPV6_HDR_TC_SHIFT)
#define CNE_IPV6_HDR_DSCP_MASK (0xfc << CNE_IPV6_HDR_TC_SHIFT)
#define CNE_IPV6_HDR_ECN_MASK  (0x03 << CNE_IPV6_HDR_TC_SHIFT)
#define CNE_IPV6_HDR_ECN_CE    CNE_IPV6_HDR_ECN_MASK
 
#define CNE_IPV6_MIN_MTU 1280 
static inline uint16_t
cne_ipv6_phdr_cksum(const struct cne_ipv6_hdr *ipv6_hdr, uint64_t ol_flags __cne_unused)
{
    uint32_t sum;
    struct {
        cne_be32_t len;   /* L4 length. */
        cne_be32_t proto; /* L4 protocol - top 3 bytes must be zero */
    } psd_hdr;
 
    psd_hdr.proto = (uint32_t)(ipv6_hdr->proto << 24);
    psd_hdr.len   = ipv6_hdr->payload_len;
 
    sum = __cne_raw_cksum(ipv6_hdr->src_addr,
                          sizeof(ipv6_hdr->src_addr) + sizeof(ipv6_hdr->dst_addr), 0);
    sum = __cne_raw_cksum(&psd_hdr, sizeof(psd_hdr), sum);
    return __cne_raw_cksum_reduce(sum);
}
 
static inline uint16_t
cne_ipv6_udptcp_cksum(const struct cne_ipv6_hdr *ipv6_hdr, const void *l4_hdr)
{
    uint32_t cksum;
    uint32_t l4_len;
 
    l4_len = be16toh(ipv6_hdr->payload_len);
 
    cksum = cne_raw_cksum(l4_hdr, l4_len);
    cksum += cne_ipv6_phdr_cksum(ipv6_hdr, 0);
 
    cksum = ((cksum & 0xffff0000) >> 16) + (cksum & 0xffff);
    cksum = (~cksum) & 0xffff;
    if (cksum == 0)
        cksum = 0xffff;
 
    return (uint16_t)cksum;
}
 
#define CNE_IPV6_EHDR_MF_SHIFT 0
#define CNE_IPV6_EHDR_MF_MASK  1
#define CNE_IPV6_EHDR_FO_SHIFT 3
#define CNE_IPV6_EHDR_FO_MASK  (~((1 << CNE_IPV6_EHDR_FO_SHIFT) - 1))
#define CNE_IPV6_EHDR_FO_ALIGN (1 << CNE_IPV6_EHDR_FO_SHIFT)
 
#define CNE_IPV6_FRAG_USED_MASK (CNE_IPV6_EHDR_MF_MASK | CNE_IPV6_EHDR_FO_MASK)
 
#define CNE_IPV6_GET_MF(x) ((x)&CNE_IPV6_EHDR_MF_MASK)
#define CNE_IPV6_GET_FO(x) ((x) >> CNE_IPV6_EHDR_FO_SHIFT)
 
#define CNE_IPV6_SET_FRAG_DATA(fo, mf) (((fo)&CNE_IPV6_EHDR_FO_MASK) | ((mf)&CNE_IPV6_EHDR_MF_MASK))
 
struct cne_ipv6_fragment_ext {
    uint8_t next_header;  
    uint8_t reserved;     
    cne_be16_t frag_data; 
    cne_be32_t id;        
} __cne_packed;
 
/* IPv6 fragment extension header size */
#define CNE_IPV6_FRAG_HDR_SIZE sizeof(struct cne_ipv6_fragment_ext)
 
static inline int
cne_ipv6_get_next_ext(const uint8_t *p, int proto, size_t *ext_len)
{
    int next_proto;
 
    switch (proto) {
    case IPPROTO_AH:
        next_proto = *p++;
        *ext_len   = (*p + 2) * sizeof(uint32_t);
        break;
 
    case IPPROTO_HOPOPTS:
    case IPPROTO_ROUTING:
    case IPPROTO_DSTOPTS:
        next_proto = *p++;
        *ext_len   = (*p + 1) * sizeof(uint64_t);
        break;
 
    case IPPROTO_FRAGMENT:
        next_proto = *p;
        *ext_len   = CNE_IPV6_FRAG_HDR_SIZE;
        break;
 
    default:
        return -EINVAL;
    }
 
    return next_proto;
}
 
#ifdef __cplusplus
}
#endif
 
#endif /* _CNE_IP_H_ */