utils.h

/****************************************************************************/
/*          pfixtools: a collection of postfix related tools                */
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#ifndef PFIXTOOLS_UTILS_H
#define PFIXTOOLS_UTILS_H

#include "common.h"
#include "buffer.h"

typedef uint32_t ip4_t;

typedef uint8_t ip6_t[16];

typedef union ip_t {
    ip4_t v4;
    ip6_t v6;
} ip_t;

typedef uint8_t cidrlen_t;


/** Parse an IPv4 from a string.
 */
__attribute__((nonnull))
bool ip_parse_4(ip4_t *restrict ip, const char* restrict txt, ssize_t len);

/** Read an IPv4 from a buffer in network order.
 */
__attribute__((nonnull))
static inline ip4_t ip_read_4(const uint8_t *restrict data);

/** Compute the IPv4 network mask for the given CIDR length
 */
__attribute__((pure))
static ip4_t ip_mask_4(cidrlen_t cidr_len);

/** Compare two IPv4 with the given cidr mask len.
 */
static inline bool ip_compare_4(ip4_t ip1, ip4_t ip2, cidrlen_t cidr_len);

/** Print an IPv4 in the buffer.
 */
bool ip_print_4(buffer_t *buffer, ip4_t ip, bool display, bool reverse);


/** Parse an IPv6 from a string.
 */
__attribute__((nonnull))
bool ip_parse_6(ip6_t ip, const char* restrict txt, ssize_t len);

/** Compare two IPv6 with the given cird mask len.
 */
static inline bool ip_compare_6(const ip6_t ip1, const ip6_t ip2,
                                cidrlen_t cidr_len);

/** Print an IPv6 in the buffer.
 */
bool ip_print_6(buffer_t *buffer, const ip6_t ip, bool display, bool reverse);


static inline ip4_t ip_mask_4(cidrlen_t cidr_len)
{
    if (likely(cidr_len > 0 && cidr_len <= 32)) {
        return (0xffffffff) << (32 - cidr_len);
    } else if (likely(cidr_len == 0)) {
        return 0;
    } else {
        return 0xffffffff;
    }
}

static inline bool ip_compare_4(ip4_t ip1, ip4_t ip2, cidrlen_t cidr_len)
{
    const ip4_t mask = ip_mask_4(cidr_len);
    return (ip1 & mask) == (ip2 & mask);
}

static inline bool ip_compare_6(const ip6_t ip1, const ip6_t ip2,
                                cidrlen_t cidr_len)
{
    size_t bytes = cidr_len >> 3;
    int bits  = cidr_len & 7;
    if (bytes > 0) {
        if (memcmp(ip1, ip2, bytes) != 0) {
            return false;
        }
    }
    if (bits > 0) {
        return (ip1[bytes] >> (8 - bits)) == (ip2[bytes] >> (8 - bits));
    }
    return true;
}

static inline ip4_t ip_read_4(const uint8_t *restrict data) {
    return (ip4_t)(data[0] << 24)
        | (ip4_t)((data[1]) << 16)
        | (ip4_t)((data[2]) << 8)
        | (ip4_t)data[3];
}

#endif

/* vim:set et sw=4 sts=4 sws=4: */