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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:25:50 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:25:50 +0000 |
commit | 19f4f86bfed21c5326ed2acebe1163f3a83e832b (patch) | |
tree | d59b9989ce55ed23693e80974d94c856f1c2c8b1 /src/basic/in-addr-util.c | |
parent | Initial commit. (diff) | |
download | systemd-upstream/241.tar.xz systemd-upstream/241.zip |
Adding upstream version 241.upstream/241upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/basic/in-addr-util.c')
-rw-r--r-- | src/basic/in-addr-util.c | 622 |
1 files changed, 622 insertions, 0 deletions
diff --git a/src/basic/in-addr-util.c b/src/basic/in-addr-util.c new file mode 100644 index 0000000..2bffe47 --- /dev/null +++ b/src/basic/in-addr-util.c @@ -0,0 +1,622 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <arpa/inet.h> +#include <endian.h> +#include <errno.h> +#include <net/if.h> +#include <stdint.h> +#include <stdlib.h> + +#include "alloc-util.h" +#include "in-addr-util.h" +#include "macro.h" +#include "parse-util.h" +#include "util.h" + +bool in4_addr_is_null(const struct in_addr *a) { + assert(a); + + return a->s_addr == 0; +} + +int in_addr_is_null(int family, const union in_addr_union *u) { + assert(u); + + if (family == AF_INET) + return in4_addr_is_null(&u->in); + + if (family == AF_INET6) + return IN6_IS_ADDR_UNSPECIFIED(&u->in6); + + return -EAFNOSUPPORT; +} + +bool in4_addr_is_link_local(const struct in_addr *a) { + assert(a); + + return (be32toh(a->s_addr) & UINT32_C(0xFFFF0000)) == (UINT32_C(169) << 24 | UINT32_C(254) << 16); +} + +int in_addr_is_link_local(int family, const union in_addr_union *u) { + assert(u); + + if (family == AF_INET) + return in4_addr_is_link_local(&u->in); + + if (family == AF_INET6) + return IN6_IS_ADDR_LINKLOCAL(&u->in6); + + return -EAFNOSUPPORT; +} + +int in_addr_is_multicast(int family, const union in_addr_union *u) { + assert(u); + + if (family == AF_INET) + return IN_MULTICAST(be32toh(u->in.s_addr)); + + if (family == AF_INET6) + return IN6_IS_ADDR_MULTICAST(&u->in6); + + return -EAFNOSUPPORT; +} + +bool in4_addr_is_localhost(const struct in_addr *a) { + assert(a); + + /* All of 127.x.x.x is localhost. */ + return (be32toh(a->s_addr) & UINT32_C(0xFF000000)) == UINT32_C(127) << 24; +} + +int in_addr_is_localhost(int family, const union in_addr_union *u) { + assert(u); + + if (family == AF_INET) + return in4_addr_is_localhost(&u->in); + + if (family == AF_INET6) + return IN6_IS_ADDR_LOOPBACK(&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); + + if (family == AF_INET) + return a->in.s_addr == b->in.s_addr; + + if (family == AF_INET6) + return + a->in6.s6_addr32[0] == b->in6.s6_addr32[0] && + a->in6.s6_addr32[1] == b->in6.s6_addr32[1] && + a->in6.s6_addr32[2] == b->in6.s6_addr32[2] && + a->in6.s6_addr32[3] == b->in6.s6_addr32[3]; + + return -EAFNOSUPPORT; +} + +int in_addr_prefix_intersect( + int family, + const union in_addr_union *a, + unsigned aprefixlen, + const union in_addr_union *b, + unsigned bprefixlen) { + + unsigned m; + + assert(a); + assert(b); + + /* Checks whether there are any addresses that are in both + * networks */ + + m = MIN(aprefixlen, bprefixlen); + + if (family == AF_INET) { + uint32_t x, nm; + + x = be32toh(a->in.s_addr ^ b->in.s_addr); + nm = (m == 0) ? 0 : 0xFFFFFFFFUL << (32 - m); + + return (x & nm) == 0; + } + + if (family == AF_INET6) { + unsigned i; + + if (m > 128) + m = 128; + + for (i = 0; i < 16; i++) { + uint8_t x, nm; + + x = a->in6.s6_addr[i] ^ b->in6.s6_addr[i]; + + if (m < 8) + nm = 0xFF << (8 - m); + else + nm = 0xFF; + + if ((x & nm) != 0) + return 0; + + if (m > 8) + m -= 8; + else + m = 0; + } + + return 1; + } + + return -EAFNOSUPPORT; +} + +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 + * positive it that succeeds, or 0 if this overflows. */ + + if (prefixlen <= 0) + return 0; + + if (family == AF_INET) { + uint32_t c, n; + + if (prefixlen > 32) + prefixlen = 32; + + c = be32toh(u->in.s_addr); + n = c + (1UL << (32 - prefixlen)); + if (n < c) + return 0; + n &= 0xFFFFFFFFUL << (32 - prefixlen); + + u->in.s_addr = htobe32(n); + return 1; + } + + if (family == AF_INET6) { + struct in6_addr add = {}, result; + uint8_t overflow = 0; + unsigned i; + + if (prefixlen > 128) + prefixlen = 128; + + /* First calculate what we have to add */ + add.s6_addr[(prefixlen-1) / 8] = 1 << (7 - (prefixlen-1) % 8); + + for (i = 16; i > 0; i--) { + unsigned j = i - 1; + + result.s6_addr[j] = u->in6.s6_addr[j] + add.s6_addr[j] + overflow; + overflow = (result.s6_addr[j] < u->in6.s6_addr[j]); + } + + if (overflow) + return 0; + + u->in6 = result; + return 1; + } + + return -EAFNOSUPPORT; +} + +int in_addr_to_string(int family, const union in_addr_union *u, char **ret) { + char *x; + size_t l; + + assert(u); + assert(ret); + + if (family == AF_INET) + l = INET_ADDRSTRLEN; + else if (family == AF_INET6) + l = INET6_ADDRSTRLEN; + else + return -EAFNOSUPPORT; + + x = new(char, l); + if (!x) + return -ENOMEM; + + errno = 0; + if (!inet_ntop(family, u, x, l)) { + free(x); + return errno > 0 ? -errno : -EINVAL; + } + + *ret = x; + return 0; +} + +int in_addr_ifindex_to_string(int family, const union in_addr_union *u, int ifindex, char **ret) { + size_t l; + char *x; + int r; + + assert(u); + assert(ret); + + /* Much like in_addr_to_string(), but optionally appends the zone interface index to the address, to properly + * handle IPv6 link-local addresses. */ + + if (family != AF_INET6) + goto fallback; + if (ifindex <= 0) + goto fallback; + + r = in_addr_is_link_local(family, u); + if (r < 0) + return r; + if (r == 0) + goto fallback; + + l = INET6_ADDRSTRLEN + 1 + DECIMAL_STR_MAX(ifindex) + 1; + x = new(char, l); + if (!x) + return -ENOMEM; + + errno = 0; + if (!inet_ntop(family, u, x, l)) { + free(x); + return errno > 0 ? -errno : -EINVAL; + } + + sprintf(strchr(x, 0), "%%%i", ifindex); + *ret = x; + + return 0; + +fallback: + return in_addr_to_string(family, u, ret); +} + +int in_addr_from_string(int family, const char *s, union in_addr_union *ret) { + union in_addr_union buffer; + assert(s); + + if (!IN_SET(family, AF_INET, AF_INET6)) + return -EAFNOSUPPORT; + + errno = 0; + if (inet_pton(family, s, ret ?: &buffer) <= 0) + return errno > 0 ? -errno : -EINVAL; + + return 0; +} + +int in_addr_from_string_auto(const char *s, int *ret_family, union in_addr_union *ret) { + int r; + + assert(s); + + r = in_addr_from_string(AF_INET, s, ret); + if (r >= 0) { + if (ret_family) + *ret_family = AF_INET; + return 0; + } + + r = in_addr_from_string(AF_INET6, s, ret); + if (r >= 0) { + if (ret_family) + *ret_family = AF_INET6; + return 0; + } + + return -EINVAL; +} + +int in_addr_ifindex_from_string_auto(const char *s, int *family, union in_addr_union *ret, int *ifindex) { + _cleanup_free_ char *buf = NULL; + const char *suffix; + int r, ifi = 0; + + assert(s); + assert(family); + assert(ret); + + /* Similar to in_addr_from_string_auto() but also parses an optionally appended IPv6 zone suffix ("scope id") + * if one is found. */ + + suffix = strchr(s, '%'); + if (suffix) { + + if (ifindex) { + /* If we shall return the interface index, try to parse it */ + r = parse_ifindex(suffix + 1, &ifi); + if (r < 0) { + unsigned u; + + u = if_nametoindex(suffix + 1); + if (u <= 0) + return -errno; + + ifi = (int) u; + } + } + + buf = strndup(s, suffix - s); + if (!buf) + return -ENOMEM; + + s = buf; + } + + r = in_addr_from_string_auto(s, family, ret); + if (r < 0) + return r; + + if (ifindex) + *ifindex = ifi; + + return r; +} + +unsigned char in4_addr_netmask_to_prefixlen(const struct in_addr *addr) { + assert(addr); + + return 32U - u32ctz(be32toh(addr->s_addr)); +} + +struct in_addr* in4_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 in4_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 in4_addr_default_subnet_mask(const struct in_addr *addr, struct in_addr *mask) { + unsigned char prefixlen; + int r; + + assert(addr); + assert(mask); + + r = in4_addr_default_prefixlen(addr, &prefixlen); + if (r < 0) + return r; + + in4_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 (!in4_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; +} + +int in_addr_prefix_covers(int family, + const union in_addr_union *prefix, + unsigned char prefixlen, + const union in_addr_union *address) { + + union in_addr_union masked_prefix, masked_address; + int r; + + assert(prefix); + assert(address); + + masked_prefix = *prefix; + r = in_addr_mask(family, &masked_prefix, prefixlen); + if (r < 0) + return r; + + masked_address = *address; + r = in_addr_mask(family, &masked_address, prefixlen); + if (r < 0) + return r; + + return in_addr_equal(family, &masked_prefix, &masked_address); +} + +int in_addr_parse_prefixlen(int family, const char *p, unsigned char *ret) { + uint8_t u; + int r; + + if (!IN_SET(family, AF_INET, AF_INET6)) + return -EAFNOSUPPORT; + + r = safe_atou8(p, &u); + if (r < 0) + return r; + + if (u > FAMILY_ADDRESS_SIZE(family) * 8) + return -ERANGE; + + *ret = u; + return 0; +} + +int in_addr_prefix_from_string( + const char *p, + int family, + union in_addr_union *ret_prefix, + unsigned char *ret_prefixlen) { + + _cleanup_free_ char *str = NULL; + union in_addr_union buffer; + const char *e, *l; + unsigned char k; + int r; + + assert(p); + + if (!IN_SET(family, AF_INET, AF_INET6)) + return -EAFNOSUPPORT; + + e = strchr(p, '/'); + if (e) { + str = strndup(p, e - p); + if (!str) + return -ENOMEM; + + l = str; + } else + l = p; + + r = in_addr_from_string(family, l, &buffer); + if (r < 0) + return r; + + if (e) { + r = in_addr_parse_prefixlen(family, e+1, &k); + if (r < 0) + return r; + } else + k = FAMILY_ADDRESS_SIZE(family) * 8; + + if (ret_prefix) + *ret_prefix = buffer; + if (ret_prefixlen) + *ret_prefixlen = k; + + return 0; +} + +int in_addr_prefix_from_string_auto_internal( + const char *p, + InAddrPrefixLenMode mode, + int *ret_family, + union in_addr_union *ret_prefix, + unsigned char *ret_prefixlen) { + + _cleanup_free_ char *str = NULL; + union in_addr_union buffer; + const char *e, *l; + unsigned char k; + int family, r; + + assert(p); + + e = strchr(p, '/'); + if (e) { + str = strndup(p, e - p); + if (!str) + return -ENOMEM; + + l = str; + } else + l = p; + + r = in_addr_from_string_auto(l, &family, &buffer); + if (r < 0) + return r; + + if (e) { + r = in_addr_parse_prefixlen(family, e+1, &k); + if (r < 0) + return r; + } else + switch (mode) { + case PREFIXLEN_FULL: + k = FAMILY_ADDRESS_SIZE(family) * 8; + break; + case PREFIXLEN_REFUSE: + return -ENOANO; /* To distinguish this error from others. */ + case PREFIXLEN_LEGACY: + if (family == AF_INET) { + r = in4_addr_default_prefixlen(&buffer.in, &k); + if (r < 0) + return r; + } else + k = 0; + break; + default: + assert_not_reached("Invalid prefixlen mode"); + } + + if (ret_family) + *ret_family = family; + if (ret_prefix) + *ret_prefix = buffer; + if (ret_prefixlen) + *ret_prefixlen = k; + + return 0; + +} + +static void in_addr_data_hash_func(const struct in_addr_data *a, struct siphash *state) { + siphash24_compress(&a->family, sizeof(a->family), state); + siphash24_compress(&a->address, FAMILY_ADDRESS_SIZE(a->family), state); +} + +static int in_addr_data_compare_func(const struct in_addr_data *x, const struct in_addr_data *y) { + int r; + + r = CMP(x->family, y->family); + if (r != 0) + return r; + + return memcmp(&x->address, &y->address, FAMILY_ADDRESS_SIZE(x->family)); +} + +DEFINE_HASH_OPS(in_addr_data_hash_ops, struct in_addr_data, in_addr_data_hash_func, in_addr_data_compare_func); 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