| /* |
| * IPv4/v6 address functions. |
| * Copyright (C) 2017 by Harald Welte <laforge@gnumonks.org> |
| * |
| * The contents of this file may be used under the terms of the GNU |
| * General Public License Version 2, provided that the above copyright |
| * notice and this permission notice is included in all copies or |
| * substantial portions of the software. |
| * |
| */ |
| |
| #include "../lib/in46_addr.h" |
| #include "../gtp/pdp.h" |
| |
| #include <osmocom/core/utils.h> |
| |
| #include <sys/types.h> |
| #include <netinet/in.h> |
| #include <sys/socket.h> |
| #include <arpa/inet.h> |
| #include <netdb.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| /*! Return the address family of given \reff in46_addr argument */ |
| int in46a_to_af(const struct in46_addr *in) |
| { |
| switch (in->len) { |
| case 4: |
| return AF_INET; |
| case 8: |
| case 16: |
| return AF_INET6; |
| default: |
| OSMO_ASSERT(0); |
| return -1; |
| } |
| } |
| |
| /*! Convert \ref in46_addr to sockaddr_storage */ |
| int in46a_to_sas(struct sockaddr_storage *out, const struct in46_addr *in) |
| { |
| struct sockaddr_in *sin = (struct sockaddr_in *)out; |
| struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)out; |
| |
| switch (in->len) { |
| case 4: |
| sin->sin_family = AF_INET; |
| sin->sin_addr = in->v4; |
| break; |
| case 16: |
| sin6->sin6_family = AF_INET6; |
| sin6->sin6_addr = in->v6; |
| break; |
| default: |
| OSMO_ASSERT(0); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| /*! Convenience wrapper around inet_ntop() for in46_addr. |
| * \param[in] in the in46_addr to print |
| * \param[out] dst destination buffer where string representation of the address is stored |
| * \param[out] dst_size size dst. Usually it should be at least INET6_ADDRSTRLEN. |
| * \return address of dst on success, NULL on error */ |
| const char *in46a_ntop(const struct in46_addr *in, char *dst, socklen_t dst_size) |
| { |
| int af; |
| |
| if (!in || in->len == 0) { |
| strncpy(dst, "UNDEFINED", dst_size); |
| return dst; |
| } |
| |
| af = in46a_to_af(in); |
| if (af < 0) |
| return NULL; |
| |
| return inet_ntop(af, (const void *) &in->v4, dst, dst_size); |
| } |
| |
| /* like inet_ntoa() */ |
| const char *in46a_ntoa(const struct in46_addr *in46) |
| { |
| static char addrstr_buf[256]; |
| if (in46a_ntop(in46, addrstr_buf, sizeof(addrstr_buf)) < 0) |
| return "INVALID"; |
| else |
| return addrstr_buf; |
| } |
| |
| const char *in46p_ntoa(const struct in46_prefix *in46p) |
| { |
| static char addrstr_buf[256]; |
| snprintf(addrstr_buf, sizeof(addrstr_buf), "%s/%u", in46a_ntoa(&in46p->addr), in46p->prefixlen); |
| return addrstr_buf; |
| } |
| |
| /*! Determine if two in46_addr are equal or not |
| * \returns 1 in case they are equal; 0 otherwise */ |
| int in46a_equal(const struct in46_addr *a, const struct in46_addr *b) |
| { |
| if (a->len == b->len && !memcmp(&a->v6, &b->v6, a->len)) |
| return 1; |
| else |
| return 0; |
| } |
| |
| /*! Determine if two in46_addr prefix are equal or not |
| * The prefix length is determined by the shortest of the prefixes of a and b |
| * \returns 1 in case the common prefix are equal; 0 otherwise */ |
| int in46a_prefix_equal(const struct in46_addr *a, const struct in46_addr *b) |
| { |
| unsigned int len; |
| if (a->len > b->len) |
| len = b->len; |
| else |
| len = a->len; |
| |
| if (!memcmp(&a->v6, &b->v6, len)) |
| return 1; |
| else |
| return 0; |
| } |
| |
| /*! Match if IPv6 addr1 + addr2 are within same \a mask */ |
| static int ipv6_within_mask(const struct in6_addr *addr1, const struct in6_addr *addr2, |
| const struct in6_addr *mask) |
| { |
| struct in6_addr masked = *addr2; |
| #if defined(__linux__) |
| masked.s6_addr32[0] &= mask->s6_addr32[0]; |
| masked.s6_addr32[1] &= mask->s6_addr32[1]; |
| masked.s6_addr32[2] &= mask->s6_addr32[2]; |
| masked.s6_addr32[3] &= mask->s6_addr32[3]; |
| #else |
| masked.__u6_addr.__u6_addr32[0] &= mask->__u6_addr.__u6_addr32[0]; |
| masked.__u6_addr.__u6_addr32[1] &= mask->__u6_addr.__u6_addr32[1]; |
| masked.__u6_addr.__u6_addr32[2] &= mask->__u6_addr.__u6_addr32[2]; |
| masked.__u6_addr.__u6_addr32[3] &= mask->__u6_addr.__u6_addr32[3]; |
| #endif |
| if (!memcmp(addr1, &masked, sizeof(struct in6_addr))) |
| return 1; |
| else |
| return 0; |
| } |
| |
| /*! Create an IPv6 netmask from the given prefix length */ |
| static void create_ipv6_netmask(struct in6_addr *netmask, int prefixlen) |
| { |
| uint32_t *p_netmask; |
| memset(netmask, 0, sizeof(struct in6_addr)); |
| if (prefixlen < 0) |
| prefixlen = 0; |
| else if (128 < prefixlen) |
| prefixlen = 128; |
| |
| #if defined(__linux__) |
| p_netmask = &netmask->s6_addr32[0]; |
| #else |
| p_netmask = &netmask->__u6_addr.__u6_addr32[0]; |
| #endif |
| while (32 < prefixlen) { |
| *p_netmask = 0xffffffff; |
| p_netmask++; |
| prefixlen -= 32; |
| } |
| if (prefixlen != 0) { |
| *p_netmask = htonl(0xFFFFFFFF << (32 - prefixlen)); |
| } |
| } |
| |
| /*! Determine if given \a addr is within given \a net + \a prefixlen |
| * Builds the netmask from \a net + \a prefixlen and matches it to \a addr |
| * \returns 1 in case of a match, 0 otherwise */ |
| int in46a_within_mask(const struct in46_addr *addr, const struct in46_addr *net, size_t prefixlen) |
| { |
| struct in_addr netmask; |
| struct in6_addr netmask6; |
| |
| if (addr->len != net->len) |
| return 0; |
| |
| switch (addr->len) { |
| case 4: |
| netmask.s_addr = htonl(0xFFFFFFFF << (32 - prefixlen)); |
| if ((addr->v4.s_addr & netmask.s_addr) == net->v4.s_addr) |
| return 1; |
| else |
| return 0; |
| case 16: |
| create_ipv6_netmask(&netmask6, prefixlen); |
| return ipv6_within_mask(&addr->v6, &net->v6, &netmask6); |
| default: |
| OSMO_ASSERT(0); |
| return 0; |
| } |
| } |
| |
| static unsigned int ipv4_netmasklen(const struct in_addr *netmask) |
| { |
| uint32_t bits = netmask->s_addr; |
| uint8_t *b = (uint8_t*) &bits; |
| unsigned int i, prefix = 0; |
| |
| for (i = 0; i < 4; i++) { |
| while (b[i] & 0x80) { |
| prefix++; |
| b[i] = b[i] << 1; |
| } |
| } |
| return prefix; |
| } |
| |
| static unsigned int ipv6_netmasklen(const struct in6_addr *netmask) |
| { |
| #if defined(__linux__) |
| #define ADDRFIELD(i) s6_addr32[i] |
| #else |
| #define ADDRFIELD(i) __u6_addr.__u6_addr32[i] |
| #endif |
| |
| unsigned int i, j, prefix = 0; |
| |
| for (j = 0; j < 4; j++) { |
| uint32_t bits = netmask->ADDRFIELD(j); |
| uint8_t *b = (uint8_t*) &bits; |
| for (i = 0; i < 4; i++) { |
| while (b[i] & 0x80) { |
| prefix++; |
| b[i] = b[i] << 1; |
| } |
| } |
| } |
| |
| #undef ADDRFIELD |
| |
| return prefix; |
| } |
| |
| /*! Convert netmask to prefix length representation |
| * \param[in] netmask in46_addr containing a netmask (consecutive list of 1-bit followed by consecutive list of 0-bit) |
| * \returns prefix length representation of the netmask (count of 1-bit from the start of the netmask) |
| */ |
| unsigned int in46a_netmasklen(const struct in46_addr *netmask) |
| { |
| switch (netmask->len) { |
| case 4: |
| return ipv4_netmasklen(&netmask->v4); |
| case 16: |
| return ipv6_netmasklen(&netmask->v6); |
| default: |
| OSMO_ASSERT(0); |
| return 0; |
| } |
| } |
| |
| /*! Convert given array of in46_addr to PDP End User Address |
| * \param[in] src Array containing 1 or 2 in46_addr |
| * \param[out] eua End User Address structure to fill |
| * \returns 0 on success; negative on error |
| * |
| * In case size is 2, this function expects to find exactly one IPv4 and one |
| * IPv6 addresses in src. */ |
| int in46a_to_eua(const struct in46_addr *src, unsigned int size, struct ul66_t *eua) |
| { |
| const struct in46_addr *src_v4, *src_v6; |
| if (size == 1) { |
| switch (src->len) { |
| case 4: |
| eua->l = 6; |
| eua->v[0] = PDP_EUA_ORG_IETF; |
| eua->v[1] = PDP_EUA_TYPE_v4; |
| memcpy(&eua->v[2], &src->v4, 4); /* Copy a 4 byte address */ |
| break; |
| case 8: |
| case 16: |
| eua->l = 18; |
| eua->v[0] = PDP_EUA_ORG_IETF; |
| eua->v[1] = PDP_EUA_TYPE_v6; |
| memcpy(&eua->v[2], &src->v6, 16); /* Copy a 16 byte address */ |
| break; |
| default: |
| OSMO_ASSERT(0); |
| return -1; |
| } |
| return 0; |
| } |
| |
| if (src[0].len == src[1].len) |
| return -1; /* we should have a v4 and a v6 address */ |
| |
| src_v4 = (src[0].len == 4) ? &src[0] : &src[1]; |
| src_v6 = (src[0].len == 4) ? &src[1] : &src[0]; |
| |
| eua->l = 22; |
| eua->v[0] = PDP_EUA_ORG_IETF; |
| eua->v[1] = PDP_EUA_TYPE_v4v6; |
| memcpy(&eua->v[2], &src_v4->v4, 4); |
| memcpy(&eua->v[6], &src_v6->v6, 16); |
| |
| return 0; |
| } |
| |
| /*! Convert given PDP End User Address to an array of in46_addr |
| * \param[in] eua End User Address structure to parse |
| * \param[out] dst Array containing 2 in46_addr |
| * \returns number of parsed addresses (1 or 2) on success; negative on error |
| * |
| * This function expects to receive an End User Address struct together with an |
| * array of 2 zeroed in46_addr structs. The in46_addr structs are filled in |
| * order, hence if the function returns 1 the parsed address will be stored in |
| * the first struct and the second one will be left intact. If 2 is returned, it |
| * is guaranteed that one of them is an IPv4 and the other one is an IPv6, but |
| * the order in which they are presented is not specified and must be |
| * discovered for instance by checking the len field of each address. |
| */ |
| int in46a_from_eua(const struct ul66_t *eua, struct in46_addr *dst) |
| { |
| if (eua->l < 2) |
| goto default_to_dyn_v4; |
| |
| if (eua->v[0] != 0xf1) |
| return -1; |
| |
| switch (eua->v[1]) { |
| case PDP_EUA_TYPE_v4: |
| dst->len = 4; |
| if (eua->l >= 6) |
| memcpy(&dst->v4, &eua->v[2], 4); /* Copy a 4 byte address */ |
| else |
| dst->v4.s_addr = 0; |
| return 1; |
| case PDP_EUA_TYPE_v6: |
| dst->len = 16; |
| if (eua->l >= 18) |
| memcpy(&dst->v6, &eua->v[2], 16); /* Copy a 16 byte address */ |
| else |
| memset(&dst->v6, 0, 16); |
| return 1; |
| case PDP_EUA_TYPE_v4v6: |
| /* 3GPP TS 29.060, section 7.7.27 */ |
| switch (eua->l) { |
| case 2: /* v4 & v6 dynamic */ |
| dst[0].v4.s_addr = 0; |
| memset(&dst[1].v6, 0, 16); |
| break; |
| case 6: /* v4 static, v6 dynamic */ |
| memcpy(&dst[0].v4, &eua->v[2], 4); |
| memset(&dst[1].v6, 0, 16); |
| break; |
| case 18: /* v4 dynamic, v6 static */ |
| dst[0].v4.s_addr = 0; |
| memcpy(&dst[1].v6, &eua->v[2], 16); |
| break; |
| case 22: /* v4 & v6 static */ |
| memcpy(&dst[0].v4, &eua->v[2], 4); |
| memcpy(&dst[1].v6, &eua->v[6], 16); |
| break; |
| default: |
| return -1; |
| } |
| dst[0].len = 4; |
| dst[1].len = 16; |
| return 2; |
| default: |
| return -1; |
| } |
| |
| default_to_dyn_v4: |
| /* assume dynamic IPv4 by default */ |
| dst->len = 4; |
| dst->v4.s_addr = 0; |
| return 1; |
| } |