X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Flibsystemd-network%2Fsd-dhcp-lease.c;h=f4979f7da73e4a5dc66a0f11c5f65d6041b0139d;hb=bab47929613f9e930dd241a01483b37d14b59c69;hp=94ba283cf093b9ca9d08e15df3509bf18dc1d680;hpb=68ceb9df6a39a7f86ffc3cf8266ca677a5d5271b;p=elogind.git diff --git a/src/libsystemd-network/sd-dhcp-lease.c b/src/libsystemd-network/sd-dhcp-lease.c index 94ba283cf..f4979f7da 100644 --- a/src/libsystemd-network/sd-dhcp-lease.c +++ b/src/libsystemd-network/sd-dhcp-lease.c @@ -30,6 +30,8 @@ #include "list.h" #include "mkdir.h" #include "fileio.h" +#include "unaligned.h" +#include "in-addr-util.h" #include "dhcp-protocol.h" #include "dhcp-internal.h" @@ -68,28 +70,26 @@ int sd_dhcp_lease_get_mtu(sd_dhcp_lease *lease, uint16_t *mtu) { return 0; } -int sd_dhcp_lease_get_dns(sd_dhcp_lease *lease, struct in_addr **addr, size_t *addr_size) { +int sd_dhcp_lease_get_dns(sd_dhcp_lease *lease, const struct in_addr **addr) { assert_return(lease, -EINVAL); assert_return(addr, -EINVAL); - assert_return(addr_size, -EINVAL); if (lease->dns_size) { - *addr_size = lease->dns_size; *addr = lease->dns; + return lease->dns_size; } else return -ENOENT; return 0; } -int sd_dhcp_lease_get_ntp(sd_dhcp_lease *lease, struct in_addr **addr, size_t *addr_size) { +int sd_dhcp_lease_get_ntp(sd_dhcp_lease *lease, const struct in_addr **addr) { assert_return(lease, -EINVAL); assert_return(addr, -EINVAL); - assert_return(addr_size, -EINVAL); if (lease->ntp_size) { - *addr_size = lease->ntp_size; *addr = lease->ntp; + return lease->ntp_size; } else return -ENOENT; @@ -171,6 +171,20 @@ int sd_dhcp_lease_get_next_server(sd_dhcp_lease *lease, struct in_addr *addr) { return 0; } +int sd_dhcp_lease_get_routes(sd_dhcp_lease *lease, struct sd_dhcp_route **routes) { + + assert_return(lease, -EINVAL); + assert_return(routes, -EINVAL); + + if (lease->static_route_size) { + *routes = lease->static_route; + return lease->static_route_size; + } else + return -ENOENT; + + return 0; +} + sd_dhcp_lease *sd_dhcp_lease_ref(sd_dhcp_lease *lease) { if (lease) assert_se(REFCNT_INC(lease->n_ref) >= 2); @@ -184,6 +198,7 @@ sd_dhcp_lease *sd_dhcp_lease_unref(sd_dhcp_lease *lease) { free(lease->domainname); free(lease->dns); free(lease->ntp); + free(lease->static_route); free(lease); } @@ -191,14 +206,11 @@ sd_dhcp_lease *sd_dhcp_lease_unref(sd_dhcp_lease *lease) { } static void lease_parse_u32(const uint8_t *option, size_t len, uint32_t *ret, uint32_t min) { - be32_t val; - assert(option); assert(ret); if (len == 4) { - memcpy(&val, option, 4); - *ret = be32toh(val); + *ret = unaligned_read_be32((be32_t*) option); if (*ret < min) *ret = min; @@ -210,14 +222,11 @@ static void lease_parse_s32(const uint8_t *option, size_t len, int32_t *ret) { } static void lease_parse_u16(const uint8_t *option, size_t len, uint16_t *ret, uint16_t min) { - be16_t val; - assert(option); assert(ret); if (len == 2) { - memcpy(&val, option, 2); - *ret = be16toh(val); + *ret = unaligned_read_be16((be16_t*) option); if (*ret < min) *ret = min; @@ -301,6 +310,111 @@ static int lease_parse_in_addrs_pairs(const uint8_t *option, size_t len, struct return lease_parse_in_addrs_aux(option, len, ret, ret_size, 2); } +static int class_prefixlen(uint8_t msb_octet, uint8_t *ret) { + if (msb_octet < 128) + /* Class A */ + *ret = 8; + else if (msb_octet < 192) + /* Class B */ + *ret = 16; + else if (msb_octet < 224) + /* Class C */ + *ret = 24; + else + /* Class D or E -- no subnet mask */ + return -ERANGE; + + return 0; +} + +static int lease_parse_routes(const uint8_t *option, size_t len, struct sd_dhcp_route **routes, + size_t *routes_size, size_t *routes_allocated) { + + struct in_addr addr; + + assert(option); + assert(routes); + assert(routes_size); + assert(routes_allocated); + + if (!len) + return 0; + + if (len % 8 != 0) + return -EINVAL; + + if (!GREEDY_REALLOC(*routes, *routes_allocated, *routes_size + (len / 8))) + return -ENOMEM; + + while (len >= 8) { + struct sd_dhcp_route *route = *routes + *routes_size; + + if (class_prefixlen(*option, &route->dst_prefixlen) < 0) { + log_error("Failed to determine destination prefix length from class based IP, ignoring"); + continue; + } + + lease_parse_be32(option, 4, &addr.s_addr); + route->dst_addr = inet_makeaddr(inet_netof(addr), 0); + option += 4; + + lease_parse_be32(option, 4, &route->gw_addr.s_addr); + option += 4; + + len -= 8; + (*routes_size)++; + } + + return 0; +} + +/* parses RFC3442 Classless Static Route Option */ +static int lease_parse_classless_routes(const uint8_t *option, size_t len, struct sd_dhcp_route **routes, + size_t *routes_size, size_t *routes_allocated) { + + assert(option); + assert(routes); + assert(routes_size); + assert(routes_allocated); + + /* option format: (subnet-mask-width significant-subnet-octets gateway-ip)* */ + + while (len > 0) { + uint8_t dst_octets; + struct sd_dhcp_route *route; + + if (!GREEDY_REALLOC(*routes, *routes_allocated, *routes_size + 1)) + return -ENOMEM; + + route = *routes + *routes_size; + + dst_octets = (*option == 0 ? 0 : ((*option - 1) / 8) + 1); + route->dst_prefixlen = *option; + option++; + len--; + + /* can't have more than 4 octets in IPv4 */ + if (dst_octets > 4 || len < dst_octets) + return -EINVAL; + + route->dst_addr.s_addr = 0; + memcpy(&route->dst_addr.s_addr, option, dst_octets); + option += dst_octets; + len -= dst_octets; + + if (len < 4) + return -EINVAL; + + lease_parse_be32(option, 4, &route->gw_addr.s_addr); + option += 4; + len -= 4; + + (*routes_size)++; + } + + return 0; +} + int dhcp_lease_parse_options(uint8_t code, uint8_t len, const uint8_t *option, void *user_data) { sd_dhcp_lease *lease = user_data; @@ -367,7 +481,8 @@ int dhcp_lease_parse_options(uint8_t code, uint8_t len, const uint8_t *option, break; case DHCP_OPTION_STATIC_ROUTE: - r = lease_parse_in_addrs_pairs(option, len, &lease->static_route, &lease->static_route_size); + r = lease_parse_routes(option, len, &lease->static_route, &lease->static_route_size, + &lease->static_route_allocated); if (r < 0) return r; @@ -394,19 +509,39 @@ int dhcp_lease_parse_options(uint8_t code, uint8_t len, const uint8_t *option, break; case DHCP_OPTION_DOMAIN_NAME: - r = lease_parse_string(option, len, &lease->domainname); + { + _cleanup_free_ char *domainname = NULL; + + r = lease_parse_string(option, len, &domainname); if (r < 0) return r; - break; + if (!hostname_is_valid(domainname) || is_localhost(domainname)) + break; + free(lease->domainname); + lease->domainname = domainname; + domainname = NULL; + + break; + } case DHCP_OPTION_HOST_NAME: - r = lease_parse_string(option, len, &lease->hostname); + { + _cleanup_free_ char *hostname = NULL; + + r = lease_parse_string(option, len, &hostname); if (r < 0) return r; - break; + if (!hostname_is_valid(hostname) || is_localhost(hostname)) + break; + + free(lease->hostname); + lease->hostname = hostname; + hostname = NULL; + break; + } case DHCP_OPTION_ROOT_PATH: r = lease_parse_string(option, len, &lease->root_path); if (r < 0) @@ -433,6 +568,14 @@ int dhcp_lease_parse_options(uint8_t code, uint8_t len, const uint8_t *option, lease_parse_bool(option, len, &lease->ip_forward_non_local); break; + + case DHCP_OPTION_CLASSLESS_STATIC_ROUTE: + r = lease_parse_classless_routes(option, len, &lease->static_route, &lease->static_route_size, + &lease->static_route_allocated); + if (r < 0) + return r; + + break; } return 0; @@ -456,10 +599,10 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) { _cleanup_free_ char *temp_path = NULL; _cleanup_fclose_ FILE *f = NULL; struct in_addr address; - struct in_addr *addresses; - size_t addresses_size; + const struct in_addr *addresses; const char *string; uint16_t mtu; + struct sd_dhcp_route *routes; int r; assert(lease); @@ -502,13 +645,17 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) { if (r >= 0) fprintf(f, "MTU=%" PRIu16 "\n", mtu); - r = sd_dhcp_lease_get_dns(lease, &addresses, &addresses_size); + fputs("DNS=", f); + r = sd_dhcp_lease_get_dns(lease, &addresses); if (r >= 0) - serialize_in_addrs(f, "DNS", addresses, addresses_size); + serialize_in_addrs(f, addresses, r); + fputs("\n", f); - r = sd_dhcp_lease_get_ntp(lease, &addresses, &addresses_size); + fputs("NTP=", f); + r = sd_dhcp_lease_get_ntp(lease, &addresses); if (r >= 0) - serialize_in_addrs(f, "NTP", addresses, addresses_size); + serialize_in_addrs(f, addresses, r); + fputs("\n", f); r = sd_dhcp_lease_get_domainname(lease, &string); if (r >= 0) @@ -522,6 +669,10 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) { if (r >= 0) fprintf(f, "ROOT_PATH=%s\n", string); + r = sd_dhcp_lease_get_routes(lease, &routes); + if (r >= 0) + serialize_dhcp_routes(f, "ROUTES", routes, r); + r = 0; fflush(f); @@ -543,7 +694,7 @@ int dhcp_lease_load(const char *lease_file, sd_dhcp_lease **ret) { _cleanup_dhcp_lease_unref_ sd_dhcp_lease *lease = NULL; _cleanup_free_ char *address = NULL, *router = NULL, *netmask = NULL, *server_address = NULL, *next_server = NULL, - *dns = NULL, *ntp = NULL, *mtu = NULL; + *dns = NULL, *ntp = NULL, *mtu = NULL, *routes = NULL; struct in_addr addr; int r; @@ -566,6 +717,7 @@ int dhcp_lease_load(const char *lease_file, sd_dhcp_lease **ret) { "DOMAINNAME", &lease->domainname, "HOSTNAME", &lease->hostname, "ROOT_PATH", &lease->root_path, + "ROUTES", &routes, NULL); if (r < 0) { if (r == -ENOENT) @@ -612,15 +764,19 @@ int dhcp_lease_load(const char *lease_file, sd_dhcp_lease **ret) { } if (dns) { - r = deserialize_in_addrs(&lease->dns, &lease->dns_size, dns); + r = deserialize_in_addrs(&lease->dns, dns); if (r < 0) return r; + + lease->dns_size = r; } if (ntp) { - r = deserialize_in_addrs(&lease->ntp, &lease->ntp_size, dns); + r = deserialize_in_addrs(&lease->ntp, ntp); if (r < 0) return r; + + lease->ntp_size = r; } if (mtu) { @@ -629,6 +785,13 @@ int dhcp_lease_load(const char *lease_file, sd_dhcp_lease **ret) { lease->mtu = u; } + if (routes) { + r = deserialize_dhcp_routes(&lease->static_route, &lease->static_route_size, + &lease->static_route_allocated, routes); + if (r < 0) + return r; + } + *ret = lease; lease = NULL; @@ -636,27 +799,20 @@ int dhcp_lease_load(const char *lease_file, sd_dhcp_lease **ret) { } int dhcp_lease_set_default_subnet_mask(sd_dhcp_lease *lease) { - uint32_t address; + struct in_addr address; + struct in_addr mask; + int r; assert(lease); - assert(lease->address != INADDR_ANY); - address = be32toh(lease->address); + address.s_addr = lease->address; /* fall back to the default subnet masks based on address class */ + r = in_addr_default_subnet_mask(&address, &mask); + if (r < 0) + return r; - if ((address >> 31) == 0x0) - /* class A, leading bits: 0 */ - lease->subnet_mask = htobe32(0xff000000); - else if ((address >> 30) == 0x2) - /* class B, leading bits 10 */ - lease->subnet_mask = htobe32(0xffff0000); - else if ((address >> 29) == 0x6) - /* class C, leading bits 110 */ - lease->subnet_mask = htobe32(0xffffff00); - else - /* class D or E, no default mask. give up */ - return -ERANGE; + lease->subnet_mask = mask.s_addr; return 0; }