From 446b49cc15ddaa97a658262a2f7fd827b505fa6b Mon Sep 17 00:00:00 2001 From: xueyunfei Date: Thu, 27 Oct 2022 18:25:00 +0800 Subject: [PATCH] dhcp server:bugfix softap excedes the range of subnet --- components/lwip/apps/dhcpserver/dhcpserver.c | 64 +++++++++++++++++--- components/lwip/test/test_lwip_apps.c | 39 +++++++++++- 2 files changed, 90 insertions(+), 13 deletions(-) diff --git a/components/lwip/apps/dhcpserver/dhcpserver.c b/components/lwip/apps/dhcpserver/dhcpserver.c index 4a65f8685a..b839f553eb 100644 --- a/components/lwip/apps/dhcpserver/dhcpserver.c +++ b/components/lwip/apps/dhcpserver/dhcpserver.c @@ -63,6 +63,42 @@ #define DHCPS_DEBUG 0 #define DHCPS_LOG printf +#define IS_INVALID_SUBNET_MASK(x) (((x-1) | x) != 0xFFFFFFFF) +/* Notes: +* 1. Class a address range 0.0.0.0~127.255.255.255. + * 2. Class b address range 128.0.0.0~191.255.255.255. + * 3. Class c address range 192.0.0.0~223.255.255.255. + */ +#define IS_VALID_CLASSA_SUBNET_MASK(mask) (mask >= 0xFF000000 && mask <= 0xFFFE0000) +#define IS_VALID_CLASSB_SUBNET_MASK(mask) (mask >= 0xFFFF0000 && mask <= 0xFFFFFE00) +#define IS_VALID_CLASSC_SUBNET_MASK(mask) (mask >= 0xFFFFFF00 && mask <= 0xFFFFFFFC) +#define IP_CLASS_HOST_NUM(mask) (0xffffffff & ~mask) + +#define DHCP_CHECK_SUBNET_MASK_IP(mask, ip) \ + do { \ + if (IS_INVALID_SUBNET_MASK(mask)) { \ + DHCPS_LOG("dhcps: Illegal subnet mask.\n"); \ + return ERR_ARG; \ + } else { \ + if (IP_CLASSA(ip)) { \ + if(!IS_VALID_CLASSA_SUBNET_MASK(mask)) { \ + DHCPS_LOG("dhcps: The subnet mask does not match the A address.\n"); \ + return ERR_ARG; \ + } \ + } else if (IP_CLASSB(ip)) { \ + if(!IS_VALID_CLASSB_SUBNET_MASK(mask)) { \ + DHCPS_LOG("dhcps: The subnet mask does not match the B address.\n"); \ + return ERR_ARG; \ + } \ + } else if (IP_CLASSC(ip)) { \ + if(!IS_VALID_CLASSC_SUBNET_MASK(mask)) { \ + DHCPS_LOG("dhcps: The subnet mask does not match the C address.\n"); \ + return ERR_ARG; \ + } \ + } \ + } \ + } while (0) + #define MAX_STATION_NUM CONFIG_LWIP_DHCPS_MAX_STATION_NUM #define DHCPS_STATE_OFFER 1 @@ -1141,23 +1177,25 @@ static void handle_dhcp(void *arg, *******************************************************************************/ static void dhcps_poll_set(dhcps_t *dhcps, u32_t ip) { - u32_t softap_ip = 0, local_ip = 0; + u32_t server_ip = 0, local_ip = 0; u32_t start_ip = 0; u32_t end_ip = 0; + u32_t temp_local_ip = 0; + u32_t host_num = 0; dhcps_lease_t *dhcps_poll = &dhcps->dhcps_poll; if (dhcps_poll->enable == true) { - softap_ip = htonl(ip); + server_ip = htonl(ip); start_ip = htonl(dhcps_poll->start_ip.addr); end_ip = htonl(dhcps_poll->end_ip.addr); /*config ip information can't contain local ip*/ - if ((start_ip <= softap_ip) && (softap_ip <= end_ip)) { + if ((start_ip <= server_ip) && (server_ip <= end_ip)) { dhcps_poll->enable = false; } else { /*config ip information must be in the same segment as the local ip*/ - softap_ip >>= 8; + server_ip >>= 8; - if (((start_ip >> 8 != softap_ip) || (end_ip >> 8 != softap_ip)) + if (((start_ip >> 8 != server_ip) || (end_ip >> 8 != server_ip)) || (end_ip - start_ip > DHCPS_MAX_LEASE)) { dhcps_poll->enable = false; } @@ -1165,19 +1203,24 @@ static void dhcps_poll_set(dhcps_t *dhcps, u32_t ip) } if (dhcps_poll->enable == false) { - local_ip = softap_ip = htonl(ip); - softap_ip &= 0xFFFFFF00; - local_ip &= 0xFF; + local_ip = server_ip = htonl(ip); + server_ip &= 0xFFFFFF00; + temp_local_ip = local_ip &= 0xFF; if (local_ip >= 0x80) { local_ip -= DHCPS_MAX_LEASE; + temp_local_ip -= DHCPS_MAX_LEASE; } else { local_ip ++; } bzero(dhcps_poll, sizeof(*dhcps_poll)); - dhcps_poll->start_ip.addr = softap_ip | local_ip; - dhcps_poll->end_ip.addr = softap_ip | (local_ip + DHCPS_MAX_LEASE - 1); + host_num = IP_CLASS_HOST_NUM(htonl(dhcps->dhcps_mask.addr)); + if (host_num > DHCPS_MAX_LEASE) { + host_num = DHCPS_MAX_LEASE; + } + dhcps_poll->start_ip.addr = server_ip | local_ip; + dhcps_poll->end_ip.addr = server_ip | (temp_local_ip + host_num - 1); dhcps_poll->start_ip.addr = htonl(dhcps_poll->start_ip.addr); dhcps_poll->end_ip.addr = htonl(dhcps_poll->end_ip.addr); } @@ -1229,6 +1272,7 @@ err_t dhcps_start(dhcps_t *dhcps, struct netif *netif, ip4_addr_t ip) IP4_ADDR(&dhcps->broadcast_dhcps, 255, 255, 255, 255); dhcps->server_address.addr = ip.addr; + DHCP_CHECK_SUBNET_MASK_IP(htonl(dhcps->dhcps_mask.addr), htonl(dhcps->server_address.addr)); dhcps_poll_set(dhcps, dhcps->server_address.addr); dhcps->client_address_plus.addr = dhcps->dhcps_poll.start_ip.addr; diff --git a/components/lwip/test/test_lwip_apps.c b/components/lwip/test/test_lwip_apps.c index d9a9f9dacd..c5c1e4ce9f 100644 --- a/components/lwip/test/test_lwip_apps.c +++ b/components/lwip/test/test_lwip_apps.c @@ -12,6 +12,7 @@ #include "lwip/sockets.h" #include "ping/ping_sock.h" #include "dhcpserver/dhcpserver.h" +#include "dhcpserver/dhcpserver_options.h" #define ETH_PING_END_BIT BIT(1) #define ETH_PING_DURATION_MS (5000) @@ -127,8 +128,9 @@ TEST_CASE("dhcp server init/deinit", "[lwip][leaks=0]") TEST_CASE("dhcp server start/stop on localhost", "[lwip]") { test_case_uses_tcpip(); - dhcps_t *dhcps = dhcps_new(); struct netif *netif; + dhcps_t *dhcps; + ip4_addr_t netmask; NETIF_FOREACH(netif) { if (netif->name[0] == 'l' && netif->name[1] == 'o') { @@ -137,8 +139,39 @@ TEST_CASE("dhcp server start/stop on localhost", "[lwip]") } TEST_ASSERT_NOT_NULL(netif); - ip4_addr_t ip = { .addr = 0x7f0001 }; - TEST_ASSERT(dhcps_start(dhcps, netif, ip) == ERR_OK); + //Class A + dhcps = dhcps_new(); + IP4_ADDR(&netmask, 255,0,0,0); + dhcps_set_option_info(dhcps, SUBNET_MASK, (void*)&netmask, sizeof(netmask)); + ip4_addr_t a_ip = { .addr = 0x7f0001 }; + IP4_ADDR(&netmask, 255,0,0,0); + TEST_ASSERT(dhcps_start(dhcps, netif, a_ip) == ERR_OK); + TEST_ASSERT(dhcps_stop(dhcps, netif) == ERR_OK); + dhcps_delete(dhcps); + + //Class B + dhcps = dhcps_new(); + IP4_ADDR(&netmask, 255,255,0,0); + dhcps_set_option_info(dhcps, SUBNET_MASK, (void*)&netmask, sizeof(netmask)); + ip4_addr_t b_ip = { .addr = 0x1000080 }; + TEST_ASSERT(dhcps_start(dhcps, netif, b_ip) == ERR_OK); + TEST_ASSERT(dhcps_stop(dhcps, netif) == ERR_OK); + dhcps_delete(dhcps); + + //Class C + dhcps = dhcps_new(); + IP4_ADDR(&netmask, 255,255,255,0); + dhcps_set_option_info(dhcps, SUBNET_MASK, (void*)&netmask, sizeof(netmask)); + ip4_addr_t c_ip = { .addr = 0x101A8C0 }; + TEST_ASSERT(dhcps_start(dhcps, netif, c_ip) == ERR_OK); + TEST_ASSERT(dhcps_stop(dhcps, netif) == ERR_OK); + dhcps_delete(dhcps); + + //Class A Subnet C + dhcps = dhcps_new(); + IP4_ADDR(&netmask, 255,255,255,0); + dhcps_set_option_info(dhcps, SUBNET_MASK, (void*)&netmask, sizeof(netmask)); + TEST_ASSERT(dhcps_start(dhcps, netif, a_ip) == ERR_ARG); TEST_ASSERT(dhcps_stop(dhcps, netif) == ERR_OK); dhcps_delete(dhcps); }