Pass ICMP configuration to user-space instead of directly applying it

diff --git a/README b/README
index 8c66ffa7c49ba149a45768c64cfdacff26c21f3f..9b56b200f1077ce8e01240fb2a0f430eaef2e9a6 100644 (file)
--- a/README
+++ b/README
@@ -29,8 +29,7 @@ especially routers. It compiles to only about 35 KB (-Os -s).
        h) Configurable SOL_MAX_RT
        i) DS-Lite AFTR-Name Option
        j) Softwire address and port mapped clients (MAP, LW4over6)
-       k) Prefix Class (experimental)
-       l) CER-ID (experimental)
+       j) CER-ID (experimental)
 
 4. Support for requesting and parsing Router Advertisements
        a) parsing of prefixes, routes, MTU and RDNSS options
@@ -78,5 +77,9 @@ Environment:
 * RA_ROUTES            A space-separated list of routes from the RA
                                Format: <address>/<length>,gateway,valid,metric
 * RA_DNS               A space-separated list of recursive DNS servers from the RA
+* RA_HOPLIMIT  Highest hop-limit received in RAs
+* RA_MTU               MTU-value received in RA
+* RA_REACHABLE ND Reachability time
+* RA_RETRANSMIT        ND Retransmit time
 * AFTR                 The DS-Lite AFTR domain name
 * MAPE / MAPT / LW4O6  Softwire rules for MAPE, MAPT and LW4O6

diff --git a/src/odhcp6c.h b/src/odhcp6c.h
index 3e2713ea25bd19e31f272820851939b9d1c8035e..ff5b9e45467045f89c11685740c66706f12096c8 100644 (file)
--- a/src/odhcp6c.h
+++ b/src/odhcp6c.h
@@ -319,6 +319,11 @@ int init_rtnetlink(void);
 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
                uint32_t pref, uint32_t valid);
 
+int ra_conf_hoplimit(int newvalue);
+int ra_conf_mtu(int newvalue);
+int ra_conf_reachable(int newvalue);
+int ra_conf_retransmit(int newvalue);
+
 int script_init(const char *path, const char *ifname);
 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 void script_call(const char *status);

diff --git a/src/ra.c b/src/ra.c
index 09d5c1d9ce5985dd6300c4dca3d53ff3c0d60849..04764c7386ddea8327c65fa5ce7c36c12c6963cc 100644 (file)
--- a/src/ra.c
+++ b/src/ra.c
@@ -165,19 +165,6 @@ static int16_t pref_to_priority(uint8_t flags)
 }
 
 
-static int update_proc(const char *sect, const char *opt, uint32_t value)
-{
-       char buf[64];
-       snprintf(buf, sizeof(buf), "/proc/sys/net/ipv6/%s/%s/%s", sect, if_name, opt);
-
-       int fd = open(buf, O_WRONLY);
-       int ret = write(fd, buf, snprintf(buf, sizeof(buf), "%u", value));
-       close(fd);
-
-       return ret;
-}
-
-
 bool ra_link_up(void)
 {
        static bool firstcall = true;
@@ -249,6 +236,38 @@ static bool ra_icmpv6_valid(struct sockaddr_in6 *source, int hlim, uint8_t *data
        return opt == end;
 }
 
+int ra_conf_hoplimit(int newvalue)
+{
+       static int value = 0;
+       if (newvalue > value)
+               value = newvalue;
+       return value;
+}
+
+int ra_conf_mtu(int newvalue)
+{
+       static int value = 0;
+       if (newvalue >= 1280 && newvalue <= 65535)
+               value = newvalue;
+       return value;
+}
+
+int ra_conf_reachable(int newvalue)
+{
+       static int value = 0;
+       if (newvalue > 0 && newvalue <= 3600000)
+               value = newvalue;
+       return value;
+}
+
+int ra_conf_retransmit(int newvalue)
+{
+       static int value = 0;
+       if (newvalue > 0 && newvalue <= 60000)
+               value = newvalue;
+       return value;
+}
+
 bool ra_process(void)
 {
        bool found = false;
@@ -324,26 +343,18 @@ bool ra_process(void)
                changed |= odhcp6c_update_entry(STATE_RA_ROUTE, &entry, 0, true);
 
                // Parse hoplimit
-               if (adv->nd_ra_curhoplimit)
-                       update_proc("conf", "hop_limit", adv->nd_ra_curhoplimit);
+               ra_conf_hoplimit(adv->nd_ra_curhoplimit);
 
                // Parse ND parameters
-               uint32_t reachable = ntohl(adv->nd_ra_reachable);
-               if (reachable > 0 && reachable <= 3600000)
-                       update_proc("neigh", "base_reachable_time_ms", reachable);
-
-               uint32_t retransmit = ntohl(adv->nd_ra_retransmit);
-               if (retransmit > 0 && retransmit <= 60000)
-                       update_proc("neigh", "retrans_time_ms", retransmit);
-
+               ra_conf_reachable(ntohl(adv->nd_ra_reachable));
+               ra_conf_retransmit(ntohl(adv->nd_ra_retransmit));
 
                // Evaluate options
                struct icmpv6_opt *opt;
                icmpv6_for_each_option(opt, &adv[1], &buf[len]) {
                        if (opt->type == ND_OPT_MTU) {
                                uint32_t *mtu = (uint32_t*)&opt->data[2];
-                               if (ntohl(*mtu) >= 1280 && ntohl(*mtu) <= 65535)
-                                       update_proc("conf", "mtu", ntohl(*mtu));
+                               ra_conf_mtu(ntohl(*mtu));
                        } else if (opt->type == ND_OPT_ROUTE_INFORMATION && opt->len <= 3) {
                                entry.router = from.sin6_addr;
                                entry.target = any;

diff --git a/src/script.c b/src/script.c
index d99327721d6575fafad0b0d5fb73ba745d67c50a..2c342163b364f014bd99e1af5fb5bb8b8a7e3ebc 100644 (file)
--- a/src/script.c
+++ b/src/script.c
@@ -184,6 +184,15 @@ static void entry_to_env(const char *name, const void *data, size_t len, enum en
 }
 
 
+static void int_to_env(const char *name, int value)
+{
+       size_t len = 12 + strlen(name);
+       char *buf = realloc(NULL, len);
+       snprintf(buf, len, "%s=%d", name, value);
+       putenv(buf);
+}
+
+
 static void s46_to_env_portparams(const uint8_t *data, size_t len, FILE *fp)
 {
        uint8_t *odata;
@@ -366,6 +375,11 @@ void script_call(const char *status)
                entry_to_env("RA_ROUTES", ra_route, ra_route_len, ENTRY_ROUTE);
                entry_to_env("RA_DNS", ra_dns, ra_dns_len, ENTRY_HOST);
 
+               int_to_env("RA_HOPLIMIT", ra_conf_hoplimit(0));
+               int_to_env("RA_MTU", ra_conf_mtu(0));
+               int_to_env("RA_REACHABLE", ra_conf_reachable(0));
+               int_to_env("RA_RETRANSMIT", ra_conf_retransmit(0));
+
                char *buf = malloc(10 + passthru_len * 2);
                strncpy(buf, "PASSTHRU=", 10);
                script_hexlify(&buf[9], passthru, passthru_len);