From 5daba48ca7ea49064a931a544e6da7f54cc0b74c Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Sat, 5 May 2012 14:12:42 +0300 Subject: hlr_auc_gw: Use 5 bit IND for SQN updates Change the SQN generation mechanism to use not time-based Profile 2 as described in 3GPP TS 33.102 Annex C.3.2. The previous implementation used void IND (i.e.., all of SQN was SEQ1). The new default uses 5 bits of SQN as IND. The length of IND can be configured on the command line with the new -i parameter. -i0 would make hlr_auc_gw behave in the same way as the previous implementation. Signed-hostap: Jouni Malinen --- hostapd/hlr_auc_gw.c | 46 +++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 41 insertions(+), 5 deletions(-) diff --git a/hostapd/hlr_auc_gw.c b/hostapd/hlr_auc_gw.c index 91772a6..516d859 100644 --- a/hostapd/hlr_auc_gw.c +++ b/hostapd/hlr_auc_gw.c @@ -34,7 +34,11 @@ * text file in IMSI:Kc:SRES:RAND format, IMSI in ASCII, other fields as hex * strings. This is used to simulate an HLR/AuC. As such, it is not very useful * for real life authentication, but it is useful both as an example - * implementation and for EAP-SIM testing. + * implementation and for EAP-SIM/AKA/AKA' testing. + * + * SQN generation follows the not time-based Profile 2 described in + * 3GPP TS 33.102 Annex C.3.2. The length of IND is 5 bits by default, but this + * can be changed with a command line options if needed. */ #include "includes.h" @@ -50,6 +54,7 @@ static int serv_sock = -1; static char *milenage_file = NULL; static int update_milenage = 0; static int sqn_changes = 0; +static int ind_len = 5; /* GSM triplets */ struct gsm_triplet { @@ -537,6 +542,28 @@ send: } +static void inc_sqn(u8 *sqn) +{ + u64 val, seq, ind; + + /* + * SQN = SEQ | IND = SEQ1 | SEQ2 | IND + * + * The mechanism used here is not time-based, so SEQ2 is void and + * SQN = SEQ1 | IND. The length of IND is ind_len bits and the length + * of SEQ1 is 48 - ind_len bits. + */ + + /* Increment both SEQ and IND by one */ + val = ((u64) WPA_GET_BE32(sqn) << 16) | ((u64) WPA_GET_BE16(sqn + 4)); + seq = (val >> ind_len) + 1; + ind = (val + 1) & ((1 << ind_len) - 1); + val = (seq << ind_len) | ind; + WPA_PUT_BE32(sqn, val >> 16); + WPA_PUT_BE16(sqn + 4, val & 0xffff); +} + + static void aka_req_auth(int s, struct sockaddr_un *from, socklen_t fromlen, char *imsi) { @@ -556,7 +583,7 @@ static void aka_req_auth(int s, struct sockaddr_un *from, socklen_t fromlen, if (random_get_bytes(_rand, EAP_AKA_RAND_LEN) < 0) return; res_len = EAP_AKA_RES_MAX_LEN; - inc_byte_array(m->sqn, 6); + inc_sqn(m->sqn); sqn_changes = 1; printf("AKA: Milenage with SQN=%02x%02x%02x%02x%02x%02x\n", m->sqn[0], m->sqn[1], m->sqn[2], @@ -725,7 +752,8 @@ static void usage(void) "\n" "usage:\n" "hlr_auc_gw [-hu] [-s] [-g] " - "[-m]\n" + "[-m] \\\n" + " [-i]\n" "\n" "options:\n" " -h = show this usage help\n" @@ -733,7 +761,8 @@ static void usage(void) " -s = path for UNIX domain socket\n" " (default: %s)\n" " -g = path for GSM authentication triplets\n" - " -m = path for Milenage keys\n", + " -m = path for Milenage keys\n" + " -i = IND length for SQN (default: 5)\n", default_socket_path); } @@ -749,7 +778,7 @@ int main(int argc, char *argv[]) socket_path = default_socket_path; for (;;) { - c = getopt(argc, argv, "g:hm:s:u"); + c = getopt(argc, argv, "g:hi:m:s:u"); if (c < 0) break; switch (c) { @@ -759,6 +788,13 @@ int main(int argc, char *argv[]) case 'h': usage(); return 0; + case 'i': + ind_len = atoi(optarg); + if (ind_len < 0 || ind_len > 32) { + printf("Invalid IND length\n"); + return -1; + } + break; case 'm': milenage_file = optarg; break; -- cgit v1.1