Miscellaneous functions¶

group misc

Miscellaneous functions and definitions.

This section documents the various odds and ends that didn’t fit anywhere else.

• String dump functions for converting the memory model to JSON or TCL representation
• Network-related definitions, such as frame lengths, header lengths, minimum and maximum IDs
• Network address types and enums
• Address initializer macros
• Address string parsing / dumping functions
• Address comparison functions
• Prefix validation functions
• Constants for broadcast addresses and full masks.

Dump to various formats

char* lsdn_dump_context_json(struct lsdn_context * ctx)¶

Dump the internal LSDN network model in JSON format.

Return

A C string containing the context’s representation in JSON format. Caller is responsible for deallocating the string using free.

char* lsdn_dump_context_tcl(struct lsdn_context * ctx)¶

Dump the internal LSDN network model in TCL format.

Return

A C string containing the context’s representation in lsctl-compatible form. Caller is responsible for deallocating the string using free.

Defines

lsdn_mk_iface_name(ctx)¶

Generate unique name for an interface.

See

lsdn_mk_name

Parameters

• ctx: LSDN context.

ETHERNET_FRAME_LEN¶

Ethernet frame length in bytes.

IPv4_HEADER_LEN¶

IPv4 header length in bytes.

IPv6_HEADER_LEN¶

IPv6 header length in bytes.

UDP_HEADER_LEN¶

UDP header length in bytes.

VXLAN_HEADER_LEN¶

VXLAN header length in bytes.

GENEVE_HEADER_LEN¶

GENEVE header length in bytes.

NET_GENEVE_MIN_VNET_ID¶

Minimum allowed vnet id for GENEVE networks.

NET_GENEVE_MAX_VNET_ID¶

Maximum allowed vnet id for GENEVE networks.

NET_VXLAN_MIN_VNET_ID¶

Minimum allowed vnet id for VXLAN networks.

NET_VXLAN_MAX_VNET_ID¶

Maximum allowed vnet id for VXLAN networks.

NET_VLAN_MIN_VNET_ID¶

Minimum allowed vnet id for VLAN networks.

NET_VLAN_MAX_VNET_ID¶

Maximum allowed vnet id for VLAN networks.

LSDN_MAC_LEN¶

MAC address size in bytes.

LSDN_IPv4_LEN¶

IPv4 address size in bytes.

LSDN_IPv6_LEN¶

IPv6 address size in bytes.

LSDN_MK_IPV4(a, b, c, d)¶

Construct a lsdn_ip IPv4 address from a 4-tuple.

LSDN_INITIALIZER_IPV4(a, b, c, d)¶

struct literal for a lsdn_ip IPv4 address constructed from a 4-tuple.

LSDN_MK_IPV6(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p)¶

Construct a lsdn_ip IPv6 address from a 16-tuple.

LSDN_INITIALIZER_IPV6(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p)¶

struct literal for a lsdn_ip IPv6 address constructed from a 16-tuple.

LSDN_MK_MAC(a, b, c, d, e, f)¶

Construct a lsdn_mac_t from a 6-tuple.

LSDN_INITIALIZER_MAC(a, b, c, d, e, f)¶

struct literal for a lsdn_mac_t from a 6-tuple.

LSDN_MAC_STRING_LEN¶

Maximum length of MAC address string.

Five colons, six hexadecimal octets.

LSDN_IPv4_STRING_LEN¶

Maximum length of IPv4 address string.

Three dots, four decimal octets.

LSDN_IPv6_STRING_LEN¶

Maximum length of IPv6 address string.

Seven colons, sixteen hexadecimal octets.

LSDN_IP_STRING_LEN¶

Maximum length of address string for any IP address.

Typedefs

typedef union lsdn_mac lsdn_mac_t¶

MAC address.

typedef union lsdn_ipv4 lsdn_ipv4_t¶

IPv4 address.

typedef union lsdn_ipv6 lsdn_ipv6_t¶

IPv6 address.

typedef struct lsdn_ip lsdn_ip_t¶

IP address (any version).

Enums

enum lsdn_ipv¶

IP protocol version.

Values:

LSDN_IPv4 = 4¶

IPv4.

LSDN_IPv6 = 6¶

IPv6.

Functions

lsdn_err_t lsdn_parse_mac(lsdn_mac_t * mac, const char * ascii)¶

Parse MAC address string into lsdn_mac_t.

Parameters

• ascii: MAC address string.
• mac: parsed MAC address struct.

Return Value

• LSDNE_OK: if parsed successfully.
• LSDNE_PARSE: if ascii could not be parsed into a MAC address.

bool lsdn_mac_eq(lsdn_mac_t a, lsdn_mac_t b)¶

Compare two lsdn_mac_t for equality.

Return

true if a and b are equal, false otherwise.

Parameters

• a: MAC address.
• b: MAC address.

lsdn_err_t lsdn_parse_ip(lsdn_ip_t * ip, const char * ascii)¶

Parse IP address string into lsdn_ip_t.

Parameters

• ascii: IP address string.
• ip: parsed IP address struct.

Return Value

• LSDNE_OK: if parsed successfully.
• LSDNE_PARSE: if ascii could not be parsed into an IP address.

bool lsdn_ip_eq(lsdn_ip_t a, lsdn_ip_t b)¶

Compare two lsdn_ip_t for equality.

Return

true if a and b are equal, false otherwise.

Parameters

• a: IP address.
• b: IP address.

bool lsdn_ipv_eq(lsdn_ip_t a, lsdn_ip_t b)¶

Compare two lsdn_ip_t for IP version equality.

Return

true if both a and b are of the same IP version, false otherwise.

Parameters

• a: IP address.
• b: IP address.

void lsdn_mac_to_string(const lsdn_mac_t * mac, char * buf)¶

Format lsdn_mac_t as ASCII string.

buf must be able to hold at least LSDN_MAC_STRING_LEN bytes.

Parameters

• mac: MAC address.
• buf: destination buffer for the ASCII string.

void lsdn_ipv4_to_string(const lsdn_ipv4_t * ipv4, char * buf)¶

Format lsdn_ipv4_t as ASCII string.

buf must be able to hold at least LSDN_IPv4_STRING_LEN bytes.

Parameters

• ipv4: IPv4 address.
• buf: destination buffer for the ASCII string.

void lsdn_ipv6_to_string(const lsdn_ipv6_t * ipv6, char * buf)¶

Format lsdn_ipv6_t as ASCII string.

buf must be able to hold at least LSDN_IPv6_STRING_LEN bytes.

Parameters

• ipv6: IPv6 address.
• buf: destination buffer for the ASCII string.

void lsdn_ip_to_string(const lsdn_ip_t * ip, char * buf)¶

Format lsdn_ip_t as ASCII string.

buf must be able to hold at least LSDN_IP_STRING_LEN bytes.

Parameters

• ip: IP address.
• buf: destination buffer for the ASCII string.

lsdn_ip_t lsdn_ip_mask_from_prefix(enum lsdn_ipv v, int prefix)¶

Return an IPv4/6 address mask for the given network prefix.

Sets prefix leading bits to 1 and leaves the rest at 0. For example, lsdn_ipv4_prefix_mask(LSDN_IPV4, 24) generates address 255.255.255.0.

Return

IP address mask of the appropriate version.

Parameters

• v: IP version.
• prefix: network prefix number of leading bits to set to 1.

bool lsdn_is_prefix_valid(enum lsdn_ipv ipv, int prefix)¶

Check if the size of network prefix makes sense for given ip version.

Prefix size must not exceed number of bits of the given address.

Return

true if prefix makes sense for the IP version, false otherwise.

Parameters

• ipv: IP version.
• prefix: network prefix to check.

int lsdn_ip_prefix_from_mask(const lsdn_ip_t * mask)¶

Calculate length of prefix from a network mask.

Prefix is a number of leading 1 bits in the mask.

Return

number of leading 1 bits.

Parameters

• mask: network mask to check.

bool lsdn_ip_mask_is_prefix(const lsdn_ip_t * mask)¶

Check if the given IP address is a valid address mask.

A valid network mask is an IP address which, in bits, is a sequence of 1s followed by a sequence of 0s.

Return

true if the IP address is a valid mask, false otherwise.

Parameters

• mask: address to check.

static uint32_t lsdn_ip4_u32(const lsdn_ipv4_t * v4)¶

Convert lsdn_ipv4_t to uint32_t.

Return

IP address represented as a single uint32_t value.

Parameters

• v4: address to convert.

const char *lsdn_mk_name(struct lsdn_context *ctx, const char *type)¶

Generate unique name for an object.

The name is based on the context name, type of the object (net, phys, virt, etc.) and a unique object counter on the context. It is in the form "ctxname-type-12".

Results are saved in a reused buffer, so every subsequent call overwrites the previous results. Users need to make a copy of the returned string.

See

lsdn_mk_net_name, lsdn_mk_phys_name, lsdn_mk_virt_name, lsdn_mk_iface_name, lsdn_mk_settings_name

Return

pointer to a buffer with a generated unique name.

Parameters

• ctx: LSDN context
• type: object type (arbitrary string, usually “net”, “phys”, “virt”, “iface” or “settings”)

Variables

const lsdn_mac_t lsdn_broadcast_mac¶

Broadcast MAC address.

Its value is FF:FF:FF:FF:FF:FF.

const lsdn_mac_t lsdn_all_zeroes_mac¶

All zeroes MAC mask.

Matches every MAC address. Its value, obviously, is all zeroes.

const lsdn_mac_t lsdn_multicast_mac_mask¶

Multicast MAC address.

Its value is 01:00:00:00:00:00.

const lsdn_mac_t lsdn_single_mac_mask¶

Single MAC mask.

Network mask that matches a single MAC address. Its value is all ones.

const lsdn_ip_t lsdn_single_ipv4_mask¶

Single IPv4 mask.

Network mask that matches a single IPv4 address. Its value is all ones, or a prefix 32.

const lsdn_ip_t lsdn_single_ipv6_mask¶

Single IPv6 mask.

Network mask that matches a single IPv6 address. Its value is all ones, or a prefix 128.

union lsdn_mac¶

#include <nettypes.h>

MAC address.

Public Members

uint8_t lsdn_mac::bytes[LSDN_MAC_LEN]

address as uint8_t.

char lsdn_mac::chr[LSDN_MAC_LEN]

address as char.

union lsdn_ipv4¶

#include <nettypes.h>

IPv4 address.

Public Members

uint8_t lsdn_ipv4::bytes[LSDN_IPv4_LEN]

address as uint8_t.

char lsdn_ipv4::chr[LSDN_IPv4_LEN]

address as char.

union lsdn_ipv6¶

#include <nettypes.h>

IPv6 address.

Public Members

uint8_t lsdn_ipv6::bytes[LSDN_IPv6_LEN]

address as uint8_t.

char lsdn_ipv6::chr[LSDN_IPv6_LEN]

address as char.

struct lsdn_ip¶

#include <nettypes.h>

IP address (any version).

Public Members

lsdn_ipv v¶

IP version.

lsdn_ipv4_t v4¶

IPv4 address.

lsdn_ipv6_t v6¶

IPv6 address.