From e67b80f4739c4075b51b0a575701b73928fe0bf1 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 12 Dec 2021 17:13:54 +0100 Subject: udhcpc6: fix udhcp_find_option to actually find DHCP6 options udhcp_insert_new_option treats code for IPv6 as follows: new->data[D6_OPT_CODE] = code >> 8; new->data[D6_OPT_CODE + 1] = code & 0xff; udhcp_find_option tests the code as follows: while (opt_list && opt_list->data[OPT_CODE] < code) ... if (opt_list && opt_list->data[OPT_CODE] == code) So yes, OPT_CODE and D6_OPT_CODE are both 0, but the D6_OPT_CLIENTID = 1 value means that the 1 is in the seconds byte, and udhcp_find_option is only looking at the first byte, So the send_d6_release can never find it the created option. function old new delta udhcp_find_option 28 53 +25 attach_option 276 284 +8 udhcpc6_main 2602 2607 +5 perform_d6_release 262 267 +5 udhcpd_main 1518 1520 +2 udhcpc_main 2542 2544 +2 add_serverid_and_clientid_options 46 48 +2 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 7/0 up/down: 49/0) Total: 49 bytes Signed-off-by: Denys Vlasenko --- networking/udhcp/common.c | 29 ++++++++++++++++++++++------- networking/udhcp/common.h | 6 +++++- networking/udhcp/d6_dhcpc.c | 5 +++-- networking/udhcp/dhcpc.c | 6 +++--- networking/udhcp/dhcpd.c | 2 +- 5 files changed, 34 insertions(+), 14 deletions(-) diff --git a/networking/udhcp/common.c b/networking/udhcp/common.c index 31e525c..8e9b936 100644 --- a/networking/udhcp/common.c +++ b/networking/udhcp/common.c @@ -404,14 +404,29 @@ void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, #endif /* Find option 'code' in opt_list */ -struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code) +struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code, bool dhcpv6) { - while (opt_list && opt_list->data[OPT_CODE] < code) - opt_list = opt_list->next; + IF_NOT_UDHCPC6(bool dhcpv6 = 0;) + uint8_t cur_code; - if (opt_list && opt_list->data[OPT_CODE] == code) - return opt_list; - return NULL; + for (;;) { + if (!opt_list) + return opt_list; /* NULL */ + if (!dhcpv6) { + cur_code = opt_list->data[OPT_CODE]; + } else { +//FIXME: add support for code > 0xff + if (opt_list->data[D6_OPT_CODE] != 0) + return NULL; + cur_code = opt_list->data[D6_OPT_CODE + 1]; + } + if (cur_code >= code) { + if (cur_code == code) + return opt_list; + return NULL; + } + opt_list = opt_list->next; + } } /* Parse string to IP in network order */ @@ -499,7 +514,7 @@ static NOINLINE void attach_option( } #endif - existing = udhcp_find_option(*opt_list, optflag->code); + existing = udhcp_find_option(*opt_list, optflag->code, dhcpv6); if (!existing) { /* make a new option */ uint8_t *p = udhcp_insert_new_option(opt_list, optflag->code, length, dhcpv6); diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h index e374771..5882238 100644 --- a/networking/udhcp/common.h +++ b/networking/udhcp/common.h @@ -245,7 +245,11 @@ void udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t char *dname_dec(const uint8_t *cstr, int clen, const char *pre) FAST_FUNC; uint8_t *dname_enc(/*const uint8_t *cstr, int clen,*/ const char *src, int *retlen) FAST_FUNC; #endif -struct option_set *udhcp_find_option(struct option_set *opt_list, uint8_t code) FAST_FUNC; +#if !ENABLE_UDHCPC6 +#define udhcp_find_option(opt_list, code, dhcpv6) \ + udhcp_find_option(opt_list, code) +#endif +struct option_set *udhcp_find_option(struct option_set *opt_list, uint8_t code, bool dhcpv6) FAST_FUNC; // RFC 2131 Table 5: Fields and options used by DHCP clients // diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c index 8d11a75..9d2a8f5 100644 --- a/networking/udhcp/d6_dhcpc.c +++ b/networking/udhcp/d6_dhcpc.c @@ -888,7 +888,8 @@ int send_d6_release(struct in6_addr *server_ipv6, struct in6_addr *our_cur_ipv6) if (client6_data.ia_pd) opt_ptr = mempcpy(opt_ptr, client6_data.ia_pd, client6_data.ia_pd->len + 2+2); /* Client-id */ - ci = udhcp_find_option(client_data.options, D6_OPT_CLIENTID); +///vda + ci = udhcp_find_option(client_data.options, D6_OPT_CLIENTID, /*dhcpv6:*/ 1); if (ci) opt_ptr = mempcpy(opt_ptr, ci->data, D6_OPT_DATA + 2+2 + 6); @@ -1272,7 +1273,7 @@ int udhcpc6_main(int argc UNUSED_PARAM, char **argv) } clientid_mac_ptr = NULL; - if (!udhcp_find_option(client_data.options, D6_OPT_CLIENTID)) { + if (!udhcp_find_option(client_data.options, D6_OPT_CLIENTID, /*dhcpv6:*/ 1)) { /* not set, set the default client ID */ clientid_mac_ptr = udhcp_insert_new_option( &client_data.options, D6_OPT_CLIENTID, diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c index 331f13a..c757fb3 100644 --- a/networking/udhcp/dhcpc.c +++ b/networking/udhcp/dhcpc.c @@ -658,7 +658,7 @@ static void add_client_options(struct dhcp_packet *packet) // This will be needed if we remove -V VENDOR_STR in favor of // -x vendor:VENDOR_STR - //if (!udhcp_find_option(packet.options, DHCP_VENDOR)) + //if (!udhcp_find_option(packet.options, DHCP_VENDOR, /*dhcpv6:*/ 0)) // /* not set, set the default vendor ID */ // ...add (DHCP_VENDOR, "udhcp "BB_VER) opt... } @@ -676,7 +676,7 @@ static void add_serverid_and_clientid_options(struct dhcp_packet *packet, uint32 * If the client used a 'client identifier' when it obtained the lease, * it MUST use the same 'client identifier' in the DHCPRELEASE message. */ - ci = udhcp_find_option(client_data.options, DHCP_CLIENT_ID); + ci = udhcp_find_option(client_data.options, DHCP_CLIENT_ID, /*dhcpv6:*/ 0); if (ci) udhcp_add_binary_option(packet, ci->data); } @@ -1328,7 +1328,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) } clientid_mac_ptr = NULL; - if (!(opt & OPT_C) && !udhcp_find_option(client_data.options, DHCP_CLIENT_ID)) { + if (!(opt & OPT_C) && !udhcp_find_option(client_data.options, DHCP_CLIENT_ID, /*dhcpv6:*/ 0)) { /* not suppressed and not set, create default client ID */ clientid_mac_ptr = udhcp_insert_new_option( &client_data.options, DHCP_CLIENT_ID, diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c index 0f5edb7..66750e2 100644 --- a/networking/udhcp/dhcpd.c +++ b/networking/udhcp/dhcpd.c @@ -935,7 +935,7 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv) bb_simple_info_msg("started, v"BB_VER); - option = udhcp_find_option(server_data.options, DHCP_LEASE_TIME); + option = udhcp_find_option(server_data.options, DHCP_LEASE_TIME, /*dhcpv6:*/ 0); server_data.max_lease_sec = DEFAULT_LEASE_TIME; if (option) { move_from_unaligned32(server_data.max_lease_sec, option->data + OPT_DATA); -- cgit v1.1