diff options
| -rw-r--r-- | src/dhcpv4.c | 110 |
1 files changed, 54 insertions, 56 deletions
diff --git a/src/dhcpv4.c b/src/dhcpv4.c index 905f66f..9d21423 100644 --- a/src/dhcpv4.c +++ b/src/dhcpv4.c @@ -898,55 +898,71 @@ static void handle_dhcpv4(void *addr, void *data, size_t len, #endif } +static bool dhcpv4_insert_assignment(struct list_head *list, struct dhcp_assignment *a, + uint32_t addr) +{ + uint32_t h_addr = ntohl(addr); + struct dhcp_assignment *c; + + list_for_each_entry(c, list, head) { + uint32_t c_addr = ntohl(c->addr); + + if (c_addr == h_addr) + return false; + + if (c_addr > h_addr) + break; + } + + /* Insert new node before c (might match list head) */ + a->addr = addr; + list_add_tail(&a->head, &c->head); + + return true; +} + +static char* ip4toa(uint32_t addr) +{ + static char buf[16]; + + snprintf(buf, sizeof(buf), "%u.%u.%u.%u", + ((uint8_t *)&addr)[0], ((uint8_t *)&addr)[1], + ((uint8_t *)&addr)[2], ((uint8_t *)&addr)[3]); + + return buf; +} + static bool dhcpv4_assign(struct interface *iface, struct dhcp_assignment *a, uint32_t raddr) { - struct dhcp_assignment *c; uint32_t start = ntohl(iface->dhcpv4_start_ip.s_addr); uint32_t end = ntohl(iface->dhcpv4_end_ip.s_addr); uint32_t count = end - start + 1; uint32_t seed = 0; + bool assigned; /* Preconfigured IP address by static lease */ if (a->addr) { - if (list_empty(&iface->dhcpv4_assignments)) { - list_add(&a->head, &iface->dhcpv4_assignments); - return true; - } + assigned = dhcpv4_insert_assignment(&iface->dhcpv4_assignments, + a, a->addr); - list_for_each_entry(c, &iface->dhcpv4_assignments, head) { - if (ntohl(c->addr) > ntohl(a->addr)) { - list_add_tail(&a->head, &c->head); - return true; - } else if (ntohl(a->addr) == ntohl(c->addr)) - return false; - } + if (assigned) + syslog(LOG_INFO, "Assigning static IP: %s", ip4toa(a->addr)); + + return assigned; } /* try to assign the IP the client asked for */ if (start <= ntohl(raddr) && ntohl(raddr) <= end && !config_find_lease_by_ipaddr(raddr)) { - if (list_empty(&iface->dhcpv4_assignments)) { - list_add(&a->head, &iface->dhcpv4_assignments); - goto raddr_out; - } + assigned = dhcpv4_insert_assignment(&iface->dhcpv4_assignments, + a, raddr); - list_for_each_entry(c, &iface->dhcpv4_assignments, head) { - if (ntohl(raddr) == ntohl(c->addr)) - break; - - if (ntohl(c->addr) > ntohl(raddr) || list_is_last(&c->head, &iface->dhcpv4_assignments)) { - list_add_tail(&a->head, - ntohl(c->addr) > ntohl(raddr) ? &c->head : &iface->dhcpv4_assignments); -raddr_out: - a->addr = raddr; - - syslog(LOG_INFO, "Assigning the IP the client asked for: %u.%u.%u.%u", - ((uint8_t *)&a->addr)[0], ((uint8_t *)&a->addr)[1], - ((uint8_t *)&a->addr)[2], ((uint8_t *)&a->addr)[3]); + if (assigned) { + syslog(LOG_INFO, "Assigning the IP the client asked for: %s", + ip4toa(a->addr)); - return true; - } + return true; } } @@ -961,38 +977,20 @@ raddr_out: for (uint32_t i = 0, try = (((uint32_t)rand()) % count) + start; i < count; ++i, try = (((try - start) + 1) % count) + start) { + uint32_t n_try = htonl(try); - if (config_find_lease_by_ipaddr(htonl(try))) + if (config_find_lease_by_ipaddr(n_try)) continue; - if (list_empty(&iface->dhcpv4_assignments)) { - list_add(&a->head, &iface->dhcpv4_assignments); - a->addr = htonl(try); + assigned = dhcpv4_insert_assignment(&iface->dhcpv4_assignments, + a, n_try); - syslog(LOG_INFO, "Assigning mapped IP (empty list): %u.%u.%u.%u", - ((uint8_t *)&a->addr)[0], ((uint8_t *)&a->addr)[1], - ((uint8_t *)&a->addr)[2], ((uint8_t *)&a->addr)[3]); + if (assigned) { + syslog(LOG_INFO, "Assigning mapped IP: %s (try %u of %u)", + ip4toa(a->addr), i + 1, count); return true; } - - list_for_each_entry(c, &iface->dhcpv4_assignments, head) { - if (try == ntohl(c->addr)) - break; - - if (ntohl(c->addr) > try || list_is_last(&c->head, &iface->dhcpv4_assignments)) { - list_add_tail(&a->head, - ntohl(c->addr) > try ? &c->head : &iface->dhcpv4_assignments); - a->addr = htonl(try); - - syslog(LOG_INFO, "Assigning mapped IP: %u.%u.%u.%u (try %u of %u)", - ((uint8_t *)&a->addr)[0], ((uint8_t *)&a->addr)[1], - ((uint8_t *)&a->addr)[2], ((uint8_t *)&a->addr)[3], - i, count); - - return true; - } - } } syslog(LOG_WARNING, "Can't assign any IP address -> address space is full"); |