X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fin-addr-util.c;h=9dc9ec82b484eb4c97976ab1de7d50cf9561eff0;hp=ffbaa74316724f8758095e50e20d8c58a735cd6b;hb=a354329f724d6ce913d2ccffb2be8f3327a67faa;hpb=0dd25fb9f005d8ab7ac4bc10a609d00569f8c56a diff --git a/src/shared/in-addr-util.c b/src/shared/in-addr-util.c index ffbaa7431..9dc9ec82b 100644 --- a/src/shared/in-addr-util.c +++ b/src/shared/in-addr-util.c @@ -23,7 +23,7 @@ #include "in-addr-util.h" -int in_addr_null(int family, union in_addr_union *u) { +int in_addr_is_null(int family, const union in_addr_union *u) { assert(u); if (family == AF_INET) @@ -39,8 +39,19 @@ int in_addr_null(int family, union in_addr_union *u) { return -EAFNOSUPPORT; } +int in_addr_is_link_local(int family, const union in_addr_union *u) { + assert(u); + + if (family == AF_INET) + return (be32toh(u->in.s_addr) & 0xFFFF0000) == (169U << 24 | 254U << 16); + + if (family == AF_INET6) + return IN6_IS_ADDR_LINKLOCAL(&u->in6); + + return -EAFNOSUPPORT; +} -int in_addr_equal(int family, union in_addr_union *a, union in_addr_union *b) { +int in_addr_equal(int family, const union in_addr_union *a, const union in_addr_union *b) { assert(a); assert(b); @@ -232,14 +243,50 @@ int in_addr_from_string_auto(const char *s, int *family, union in_addr_union *re return -EINVAL; } -static const char* const family_table[] = { - [AF_UNSPEC] = "unspec", - [AF_UNIX] = "unix", - [AF_INET] = "inet", - [AF_INET6] = "inet6", - [AF_NETLINK] = "netlink", - [AF_PACKET] = "packet", - [AF_BLUETOOTH] = "bluetooth", - [AF_NFC] = "nfc", -}; -DEFINE_STRING_TABLE_LOOKUP(family, int); +unsigned in_addr_netmask_to_prefixlen(const struct in_addr *addr) { + assert(addr); + + return 32 - u32ctz(be32toh(addr->s_addr)); +} + +int in_addr_default_prefixlen(const struct in_addr *addr, unsigned char *prefixlen) { + uint8_t msb_octet = *(uint8_t*) addr; + + /* addr may not be aligned, so make sure we only access it byte-wise */ + + assert(addr); + assert(prefixlen); + + if (msb_octet < 128) + /* class A, leading bits: 0 */ + *prefixlen = 8; + else if (msb_octet < 192) + /* class B, leading bits 10 */ + *prefixlen = 16; + else if (msb_octet < 224) + /* class C, leading bits 110 */ + *prefixlen = 24; + else + /* class D or E, no default prefixlen */ + return -ERANGE; + + return 0; +} + +int in_addr_default_subnet_mask(const struct in_addr *addr, struct in_addr *mask) { + unsigned char prefixlen; + int r; + + assert(addr); + assert(mask); + + r = in_addr_default_prefixlen(addr, &prefixlen); + if (r < 0) + return r; + + assert(prefixlen > 0 && prefixlen < 32); + + mask->s_addr = htobe32((0xffffffff << (32 - prefixlen)) & 0xffffffff); + + return 0; +}