X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Flibsystemd-network%2Fsd-icmp6-nd.c;h=8b567e3a5c73bfac2a5b550e5270267ca6bfeef8;hb=8d7f2c6a47db4bdb753b9d523d3bcb1105827991;hp=b264e793ee4e27d9e98550de95985298cf9667fe;hpb=fa94c34b083b5b4019975624453e53d0cbad2a5d;p=elogind.git diff --git a/src/libsystemd-network/sd-icmp6-nd.c b/src/libsystemd-network/sd-icmp6-nd.c index b264e793e..8b567e3a5 100644 --- a/src/libsystemd-network/sd-icmp6-nd.c +++ b/src/libsystemd-network/sd-icmp6-nd.c @@ -18,9 +18,11 @@ ***/ #include +#include #include #include #include +#include #include "socket-util.h" #include "refcnt.h" @@ -38,6 +40,22 @@ enum icmp6_nd_state { ICMP6_ROUTER_ADVERTISMENT_LISTEN = 11, }; +#define IP6_MIN_MTU (unsigned)1280 +#define ICMP6_ND_RECV_SIZE (IP6_MIN_MTU - sizeof(struct ip6_hdr)) +#define ICMP6_OPT_LEN_UNITS 8 + +typedef struct ICMP6Prefix ICMP6Prefix; + +struct ICMP6Prefix { + RefCount n_ref; + + LIST_FIELDS(ICMP6Prefix, prefixes); + + uint8_t len; + sd_event_source *timeout_valid; + struct in6_addr addr; +}; + struct sd_icmp6_nd { RefCount n_ref; @@ -46,6 +64,8 @@ struct sd_icmp6_nd { int event_priority; int index; struct ether_addr mac_addr; + uint32_t mtu; + LIST_HEAD(ICMP6Prefix, prefixes); int fd; sd_event_source *recv; sd_event_source *timeout; @@ -54,7 +74,36 @@ struct sd_icmp6_nd { void *userdata; }; -#define log_icmp6_nd(p, fmt, ...) log_meta(LOG_DEBUG, __FILE__, __LINE__, __func__, "ICMPv6 CLIENT: " fmt, ##__VA_ARGS__) +#define log_icmp6_nd(p, fmt, ...) log_internal(LOG_DEBUG, 0, __FILE__, __LINE__, __func__, "ICMPv6 CLIENT: " fmt, ##__VA_ARGS__) + +static ICMP6Prefix *icmp6_prefix_unref(ICMP6Prefix *prefix) { + if (prefix && REFCNT_DEC(prefix->n_ref) <= 0) { + prefix->timeout_valid = + sd_event_source_unref(prefix->timeout_valid); + + free(prefix); + } + + return NULL; +} + +static int icmp6_prefix_new(ICMP6Prefix **ret) { + _cleanup_free_ ICMP6Prefix *prefix = NULL; + + assert(ret); + + prefix = new0(ICMP6Prefix, 1); + if (!prefix) + return -ENOMEM; + + prefix->n_ref = REFCNT_INIT; + LIST_INIT(prefixes, prefix); + + *ret = prefix; + prefix = NULL; + + return 0; +} static void icmp6_nd_notify(sd_icmp6_nd *nd, int event) { @@ -87,7 +136,7 @@ int sd_icmp6_nd_set_mac(sd_icmp6_nd *nd, const struct ether_addr *mac_addr) { if (mac_addr) memcpy(&nd->mac_addr, mac_addr, sizeof(nd->mac_addr)); else - memset(&nd->mac_addr, 0x00, sizeof(nd->mac_addr)); + zero(nd->mac_addr); return 0; @@ -145,11 +194,18 @@ static int icmp6_nd_init(sd_icmp6_nd *nd) { } sd_icmp6_nd *sd_icmp6_nd_unref(sd_icmp6_nd *nd) { - if (nd && REFCNT_DEC(nd->n_ref) <= 0) { + if (nd && REFCNT_DEC(nd->n_ref) == 0) { + ICMP6Prefix *prefix, *p; icmp6_nd_init(nd); sd_icmp6_nd_detach_event(nd); + LIST_FOREACH_SAFE(prefixes, prefix, p, nd->prefixes) { + LIST_REMOVE(prefixes, nd->prefixes, prefix); + + prefix = icmp6_prefix_unref(prefix); + } + free(nd); } @@ -173,50 +229,135 @@ int sd_icmp6_nd_new(sd_icmp6_nd **ret) { nd->index = -1; nd->fd = -1; + LIST_HEAD_INIT(nd->prefixes); + *ret = nd; nd = NULL; return 0; } +int sd_icmp6_ra_get_mtu(sd_icmp6_nd *nd, uint32_t *mtu) { + assert_return(nd, -EINVAL); + assert_return(mtu, -EINVAL); + + if (nd->mtu == 0) + return -ENOMSG; + + *mtu = nd->mtu; + + return 0; +} + +static int icmp6_ra_parse(sd_icmp6_nd *nd, struct nd_router_advert *ra, + ssize_t len) { + void *opt; + struct nd_opt_hdr *opt_hdr; + + assert_return(nd, -EINVAL); + assert_return(ra, -EINVAL); + + len -= sizeof(*ra); + if (len < ICMP6_OPT_LEN_UNITS) { + log_icmp6_nd(nd, "Router Advertisement below minimum length"); + + return -ENOMSG; + } + + opt = ra + 1; + opt_hdr = opt; + + while (len != 0 && len >= opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS) { + struct nd_opt_mtu *opt_mtu; + uint32_t mtu; + + if (opt_hdr->nd_opt_len == 0) + return -ENOMSG; + + switch (opt_hdr->nd_opt_type) { + case ND_OPT_MTU: + opt_mtu = opt; + + mtu = be32toh(opt_mtu->nd_opt_mtu_mtu); + + if (mtu != nd->mtu) { + nd->mtu = MAX(mtu, IP6_MIN_MTU); + + log_icmp6_nd(nd, "Router Advertisement link MTU %d using %d", + mtu, nd->mtu); + } + + break; + + } + + len -= opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS; + opt = (void *)((char *)opt + + opt_hdr->nd_opt_len * ICMP6_OPT_LEN_UNITS); + opt_hdr = opt; + } + + if (len > 0) + log_icmp6_nd(nd, "Router Advertisement contains %zd bytes of trailing garbage", len); + + return 0; +} + static int icmp6_router_advertisment_recv(sd_event_source *s, int fd, uint32_t revents, void *userdata) { sd_icmp6_nd *nd = userdata; + int r, buflen = 0; ssize_t len; - struct nd_router_advert ra; + _cleanup_free_ struct nd_router_advert *ra = NULL; int event = ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE; assert(s); assert(nd); assert(nd->event); - /* only interested in Managed/Other flag */ - len = read(fd, &ra, sizeof(ra)); - if ((size_t)len < sizeof(ra)) + r = ioctl(fd, FIONREAD, &buflen); + if (r < 0 || buflen <= 0) + buflen = ICMP6_ND_RECV_SIZE; + + ra = malloc(buflen); + if (!ra) + return -ENOMEM; + + len = read(fd, ra, buflen); + if (len < 0) { + log_icmp6_nd(nd, "Could not receive message from UDP socket: %m"); return 0; + } - if (ra.nd_ra_type != ND_ROUTER_ADVERT) + if (ra->nd_ra_type != ND_ROUTER_ADVERT) return 0; - if (ra.nd_ra_code != 0) + if (ra->nd_ra_code != 0) return 0; nd->timeout = sd_event_source_unref(nd->timeout); nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN; - if (ra.nd_ra_flags_reserved & ND_RA_FLAG_OTHER ) + if (ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER ) event = ICMP6_EVENT_ROUTER_ADVERTISMENT_OTHER; - if (ra.nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) + if (ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) event = ICMP6_EVENT_ROUTER_ADVERTISMENT_MANAGED; - log_icmp6_nd(nd, "Received Router Advertisment flags %s/%s", - (ra.nd_ra_flags_reserved & ND_RA_FLAG_MANAGED)? "MANAGED": - "none", - (ra.nd_ra_flags_reserved & ND_RA_FLAG_OTHER)? "OTHER": - "none"); + log_icmp6_nd(nd, "Received Router Advertisement flags %s/%s", + ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED? "MANAGED": "none", + ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER? "OTHER": "none"); + + if (event != ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE) { + r = icmp6_ra_parse(nd, ra, len); + if (r < 0) { + log_icmp6_nd(nd, "Could not parse Router Advertisement: %s", + strerror(-r)); + return 0; + } + } icmp6_nd_notify(nd, event); @@ -277,6 +418,12 @@ static int icmp6_router_solicitation_timeout(sd_event_source *s, uint64_t usec, icmp6_nd_notify(nd, r); return 0; } + + r = sd_event_source_set_description(nd->timeout, "icmp6-timeout"); + if (r < 0) { + icmp6_nd_notify(nd, r); + return 0; + } } return 0; @@ -322,13 +469,20 @@ int sd_icmp6_router_solicitation_start(sd_icmp6_nd *nd) { if (r < 0) goto error; + r = sd_event_source_set_description(nd->recv, "icmp6-receive-message"); + if (r < 0) + goto error; + r = sd_event_add_time(nd->event, &nd->timeout, clock_boottime_or_monotonic(), 0, 0, icmp6_router_solicitation_timeout, nd); if (r < 0) goto error; r = sd_event_source_set_priority(nd->timeout, nd->event_priority); + if (r < 0) + goto error; + r = sd_event_source_set_description(nd->timeout, "icmp6-timeout"); error: if (r < 0) icmp6_nd_init(nd);