X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fin-addr-util.c;h=d88864b5987f7387ebd99e2ea9a689d05038c478;hb=5ffa8c818120e35c89becd938d160235c069dd12;hp=0c6ebec336446d2fc3ee67210a7ff4e8e88472a5;hpb=1716f6dcf54d4c181c2e2558e3d5414f54c8d9ca;p=elogind.git diff --git a/src/shared/in-addr-util.c b/src/shared/in-addr-util.c index 0c6ebec33..d88864b59 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(unsigned 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(unsigned 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); -int in_addr_equal(unsigned family, union in_addr_union *a, union in_addr_union *b) { + if (family == AF_INET6) + return IN6_IS_ADDR_LINKLOCAL(&u->in6); + + return -EAFNOSUPPORT; +} + +int in_addr_equal(int family, const union in_addr_union *a, const union in_addr_union *b) { assert(a); assert(b); @@ -58,7 +69,7 @@ int in_addr_equal(unsigned family, union in_addr_union *a, union in_addr_union * } int in_addr_prefix_intersect( - unsigned family, + int family, const union in_addr_union *a, unsigned aprefixlen, const union in_addr_union *b, @@ -114,7 +125,7 @@ int in_addr_prefix_intersect( return -EAFNOSUPPORT; } -int in_addr_prefix_next(unsigned family, union in_addr_union *u, unsigned prefixlen) { +int in_addr_prefix_next(int family, union in_addr_union *u, unsigned prefixlen) { assert(u); /* Increases the network part of an address by one. Returns @@ -167,7 +178,7 @@ int in_addr_prefix_next(unsigned family, union in_addr_union *u, unsigned prefix return -EAFNOSUPPORT; } -int in_addr_to_string(unsigned family, const union in_addr_union *u, char **ret) { +int in_addr_to_string(int family, const union in_addr_union *u, char **ret) { char *x; size_t l; @@ -195,7 +206,7 @@ int in_addr_to_string(unsigned family, const union in_addr_union *u, char **ret) return 0; } -int in_addr_from_string(unsigned family, const char *s, union in_addr_union *ret) { +int in_addr_from_string(int family, const char *s, union in_addr_union *ret) { assert(s); assert(ret); @@ -210,7 +221,7 @@ int in_addr_from_string(unsigned family, const char *s, union in_addr_union *ret return 0; } -int in_addr_from_string_auto(const char *s, unsigned *family, union in_addr_union *ret) { +int in_addr_from_string_auto(const char *s, int *family, union in_addr_union *ret) { int r; assert(s); @@ -232,14 +243,96 @@ int in_addr_from_string_auto(const char *s, unsigned *family, union in_addr_unio 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 char in_addr_netmask_to_prefixlen(const struct in_addr *addr) { + assert(addr); + + return 32 - u32ctz(be32toh(addr->s_addr)); +} + +struct in_addr* in_addr_prefixlen_to_netmask(struct in_addr *addr, unsigned char prefixlen) { + assert(addr); + assert(prefixlen <= 32); + + /* Shifting beyond 32 is not defined, handle this specially. */ + if (prefixlen == 0) + addr->s_addr = 0; + else + addr->s_addr = htobe32((0xffffffff << (32 - prefixlen)) & 0xffffffff); + + return 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; + + in_addr_prefixlen_to_netmask(mask, prefixlen); + return 0; +} + +int in_addr_mask(int family, union in_addr_union *addr, unsigned char prefixlen) { + assert(addr); + + if (family == AF_INET) { + struct in_addr mask; + + if (!in_addr_prefixlen_to_netmask(&mask, prefixlen)) + return -EINVAL; + + addr->in.s_addr &= mask.s_addr; + return 0; + } + + if (family == AF_INET6) { + unsigned i; + + for (i = 0; i < 16; i++) { + uint8_t mask; + + if (prefixlen >= 8) { + mask = 0xFF; + prefixlen -= 8; + } else { + mask = 0xFF << (8 - prefixlen); + prefixlen = 0; + } + + addr->in6.s6_addr[i] &= mask; + } + + return 0; + } + + return -EAFNOSUPPORT; +}