[systemd-devel] [PATCH 04/11] sd-icmp6-nd: Add link and prefix structures for ICMPv6

[Patrik Flykt]

Each ICMPv6 structure has an interface index and will therefore be
associated with an IPv6 link containing a list of of prefixes.
---
 src/libsystemd-network/sd-icmp6-nd.c | 99 ++++++++++++++++++++++++++++++++++++
 1 file changed, 99 insertions(+)

diff --git a/src/libsystemd-network/sd-icmp6-nd.c b/src/libsystemd-network/sd-icmp6-nd.c
index c9b390e..35d5f5f 100644
--- a/src/libsystemd-network/sd-icmp6-nd.c
+++ b/src/libsystemd-network/sd-icmp6-nd.c
@@ -44,6 +44,23 @@ enum icmp6_nd_state {
 #define ICMP6_ND_RECV_SIZE (IP6_MIN_MTU - sizeof(struct ip6_hdr))
 #define ICMP6_OPT_LEN_UNITS 8
 
+struct icmp6_prefix {
+        RefCount n_ref;
+
+        LIST_FIELDS(struct icmp6_prefix, prefixes);
+
+        uint8_t len;
+        sd_event_source *timeout_valid;
+        struct in6_addr addr;
+};
+
+struct icmp6_link {
+        RefCount n_ref;
+
+        uint32_t mtu;
+        LIST_HEAD(struct icmp6_prefix, prefixes);
+};
+
 struct sd_icmp6_nd {
         RefCount n_ref;
 
@@ -52,6 +69,7 @@ struct sd_icmp6_nd {
         int event_priority;
         int index;
         struct ether_addr mac_addr;
+        struct icmp6_link *link;
         int fd;
         sd_event_source *recv;
         sd_event_source *timeout;
@@ -62,6 +80,72 @@ struct sd_icmp6_nd {
 
 #define log_icmp6_nd(p, fmt, ...) log_internal(LOG_DEBUG, 0, __FILE__, __LINE__, __func__, "ICMPv6 CLIENT: " fmt, ##__VA_ARGS__)
 
+static struct icmp6_prefix *icmp6_prefix_unref(struct icmp6_prefix *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(struct icmp6_prefix **ret) {
+        _cleanup_free_ struct icmp6_prefix *prefix = NULL;
+
+        assert(ret);
+
+        prefix = new0(struct icmp6_prefix, 1);
+        if (!prefix)
+                return -ENOMEM;
+
+        prefix->n_ref = REFCNT_INIT;
+        LIST_INIT(prefixes, prefix);
+
+        *ret = prefix;
+        prefix = NULL;
+
+        return 0;
+}
+
+static struct icmp6_link *icmp6_link_unref(struct icmp6_link *link) {
+        if (link && REFCNT_DEC(link->n_ref) <= 0) {
+                struct icmp6_prefix *prefix, *p;
+
+                LIST_FOREACH_SAFE(prefixes, prefix, p, link->prefixes) {
+                        LIST_REMOVE(prefixes, link->prefixes, prefix);
+
+                        prefix = icmp6_prefix_unref(prefix);
+                }
+                free(link);
+        }
+
+        return NULL;
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(struct icmp6_link*, icmp6_link_unref);
+#define _cleanup_icmp6_link_free_ _cleanup_(icmp6_link_unrefp)
+
+static int icmp6_link_new(struct icmp6_link **ret) {
+        _cleanup_free_ struct icmp6_link *link = NULL;
+
+        assert(ret);
+
+        link = new0(struct icmp6_link, 1);
+        if (!link)
+                return -ENOMEM;
+
+        link->n_ref = REFCNT_INIT;
+
+        LIST_HEAD_INIT(link->prefixes);
+
+        *ret = link;
+        link = NULL;
+
+        return 0;
+}
+
 static void icmp6_nd_notify(sd_icmp6_nd *nd, int event)
 {
         if (nd->callback)
@@ -156,6 +240,8 @@ sd_icmp6_nd *sd_icmp6_nd_unref(sd_icmp6_nd *nd) {
                 icmp6_nd_init(nd);
                 sd_icmp6_nd_detach_event(nd);
 
+                nd->link = icmp6_link_unref(nd->link);
+
                 free(nd);
         }
 
@@ -191,6 +277,7 @@ static int icmp6_ra_parse(sd_icmp6_nd *nd, struct nd_router_advert *ra,
         struct nd_opt_hdr *opt_hdr;
 
         assert_return(nd, -EINVAL);
+        assert_return(nd->link, -EINVAL);
         assert_return(ra, -EINVAL);
 
         len -= sizeof(*ra);
@@ -225,6 +312,7 @@ static int icmp6_router_advertisment_recv(sd_event_source *s, int fd,
         int r, buflen;
         ssize_t len;
         _cleanup_free_ struct nd_router_advert *ra = NULL;
+        _cleanup_icmp6_link_free_ struct icmp6_link *link = NULL;
         int event = ICMP6_EVENT_ROUTER_ADVERTISMENT_NONE;
 
         assert(s);
@@ -251,6 +339,17 @@ static int icmp6_router_advertisment_recv(sd_event_source *s, int fd,
         if (ra->nd_ra_code != 0)
                 return 0;
 
+        if (!nd->link) {
+                r = icmp6_link_new(&link);
+                if (r < 0) {
+                        log_icmp6_nd(nd, "Could not allocate ICMP6 link struct: %m");
+                        return 0;
+                }
+
+                nd->link = link;
+                link = NULL;
+        }
+
         nd->timeout = sd_event_source_unref(nd->timeout);
 
         nd->state = ICMP6_ROUTER_ADVERTISMENT_LISTEN;
-- 
2.1.4