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authorJouni Malinen <j@w1.fi>2009-12-06 14:33:19 (GMT)
committerJouni Malinen <j@w1.fi>2009-12-06 14:33:19 (GMT)
commit0e574b07f83c0595a71267e273de28c64187b1b6 (patch)
tree0375b4ce7f56b62f828538ef0377f90aa2c61867 /hostapd/hlr_auc_gw.c
parent912321e93537c409aa4d75866df9b8e855d3e554 (diff)
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Move hlr_auc_gw into hostapd directory
This is a separate program and is used mainly with hostapd, so it is better to move this into the hostapd subdirectory now that Milenage code has already been moved into src/crypto. Milenage was the only generic component in hlr_auc_gw.
Diffstat (limited to 'hostapd/hlr_auc_gw.c')
-rw-r--r--hostapd/hlr_auc_gw.c714
1 files changed, 714 insertions, 0 deletions
diff --git a/hostapd/hlr_auc_gw.c b/hostapd/hlr_auc_gw.c
new file mode 100644
index 0000000..36934aa
--- /dev/null
+++ b/hostapd/hlr_auc_gw.c
@@ -0,0 +1,714 @@
+/*
+ * HLR/AuC testing gateway for hostapd EAP-SIM/AKA database/authenticator
+ * Copyright (c) 2005-2007, Jouni Malinen <j@w1.fi>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ *
+ * This is an example implementation of the EAP-SIM/AKA database/authentication
+ * gateway interface to HLR/AuC. It is expected to be replaced with an
+ * implementation of SS7 gateway to GSM/UMTS authentication center (HLR/AuC) or
+ * a local implementation of SIM triplet and AKA authentication data generator.
+ *
+ * hostapd will send SIM/AKA authentication queries over a UNIX domain socket
+ * to and external program, e.g., this hlr_auc_gw. This interface uses simple
+ * text-based format:
+ *
+ * EAP-SIM / GSM triplet query/response:
+ * SIM-REQ-AUTH <IMSI> <max_chal>
+ * SIM-RESP-AUTH <IMSI> Kc1:SRES1:RAND1 Kc2:SRES2:RAND2 [Kc3:SRES3:RAND3]
+ * SIM-RESP-AUTH <IMSI> FAILURE
+ *
+ * EAP-AKA / UMTS query/response:
+ * AKA-REQ-AUTH <IMSI>
+ * AKA-RESP-AUTH <IMSI> <RAND> <AUTN> <IK> <CK> <RES>
+ * AKA-RESP-AUTH <IMSI> FAILURE
+ *
+ * EAP-AKA / UMTS AUTS (re-synchronization):
+ * AKA-AUTS <IMSI> <AUTS> <RAND>
+ *
+ * IMSI and max_chal are sent as an ASCII string,
+ * Kc/SRES/RAND/AUTN/IK/CK/RES/AUTS as hex strings.
+ *
+ * The example implementation here reads GSM authentication triplets from a
+ * 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.
+ */
+
+#include "includes.h"
+#include <sys/un.h>
+
+#include "common.h"
+#include "crypto/milenage.h"
+
+static const char *default_socket_path = "/tmp/hlr_auc_gw.sock";
+static const char *socket_path;
+static int serv_sock = -1;
+
+/* GSM triplets */
+struct gsm_triplet {
+ struct gsm_triplet *next;
+ char imsi[20];
+ u8 kc[8];
+ u8 sres[4];
+ u8 _rand[16];
+};
+
+static struct gsm_triplet *gsm_db = NULL, *gsm_db_pos = NULL;
+
+/* OPc and AMF parameters for Milenage (Example algorithms for AKA). */
+struct milenage_parameters {
+ struct milenage_parameters *next;
+ char imsi[20];
+ u8 ki[16];
+ u8 opc[16];
+ u8 amf[2];
+ u8 sqn[6];
+};
+
+static struct milenage_parameters *milenage_db = NULL;
+
+#define EAP_SIM_MAX_CHAL 3
+
+#define EAP_AKA_RAND_LEN 16
+#define EAP_AKA_AUTN_LEN 16
+#define EAP_AKA_AUTS_LEN 14
+#define EAP_AKA_RES_MAX_LEN 16
+#define EAP_AKA_IK_LEN 16
+#define EAP_AKA_CK_LEN 16
+
+
+static int open_socket(const char *path)
+{
+ struct sockaddr_un addr;
+ int s;
+
+ s = socket(PF_UNIX, SOCK_DGRAM, 0);
+ if (s < 0) {
+ perror("socket(PF_UNIX)");
+ return -1;
+ }
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ os_strlcpy(addr.sun_path, path, sizeof(addr.sun_path));
+ if (bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+ perror("bind(PF_UNIX)");
+ close(s);
+ return -1;
+ }
+
+ return s;
+}
+
+
+static int read_gsm_triplets(const char *fname)
+{
+ FILE *f;
+ char buf[200], *pos, *pos2;
+ struct gsm_triplet *g = NULL;
+ int line, ret = 0;
+
+ if (fname == NULL)
+ return -1;
+
+ f = fopen(fname, "r");
+ if (f == NULL) {
+ printf("Could not open GSM tripler data file '%s'\n", fname);
+ return -1;
+ }
+
+ line = 0;
+ while (fgets(buf, sizeof(buf), f)) {
+ line++;
+
+ /* Parse IMSI:Kc:SRES:RAND */
+ buf[sizeof(buf) - 1] = '\0';
+ if (buf[0] == '#')
+ continue;
+ pos = buf;
+ while (*pos != '\0' && *pos != '\n')
+ pos++;
+ if (*pos == '\n')
+ *pos = '\0';
+ pos = buf;
+ if (*pos == '\0')
+ continue;
+
+ g = os_zalloc(sizeof(*g));
+ if (g == NULL) {
+ ret = -1;
+ break;
+ }
+
+ /* IMSI */
+ pos2 = strchr(pos, ':');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid IMSI (%s)\n",
+ fname, line, pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) >= sizeof(g->imsi)) {
+ printf("%s:%d - Too long IMSI (%s)\n",
+ fname, line, pos);
+ ret = -1;
+ break;
+ }
+ os_strlcpy(g->imsi, pos, sizeof(g->imsi));
+ pos = pos2 + 1;
+
+ /* Kc */
+ pos2 = strchr(pos, ':');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid Kc (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) != 16 || hexstr2bin(pos, g->kc, 8)) {
+ printf("%s:%d - Invalid Kc (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ /* SRES */
+ pos2 = strchr(pos, ':');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid SRES (%s)\n", fname, line,
+ pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) != 8 || hexstr2bin(pos, g->sres, 4)) {
+ printf("%s:%d - Invalid SRES (%s)\n", fname, line,
+ pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ /* RAND */
+ pos2 = strchr(pos, ':');
+ if (pos2)
+ *pos2 = '\0';
+ if (strlen(pos) != 32 || hexstr2bin(pos, g->_rand, 16)) {
+ printf("%s:%d - Invalid RAND (%s)\n", fname, line,
+ pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ g->next = gsm_db;
+ gsm_db = g;
+ g = NULL;
+ }
+ free(g);
+
+ fclose(f);
+
+ return ret;
+}
+
+
+static struct gsm_triplet * get_gsm_triplet(const char *imsi)
+{
+ struct gsm_triplet *g = gsm_db_pos;
+
+ while (g) {
+ if (strcmp(g->imsi, imsi) == 0) {
+ gsm_db_pos = g->next;
+ return g;
+ }
+ g = g->next;
+ }
+
+ g = gsm_db;
+ while (g && g != gsm_db_pos) {
+ if (strcmp(g->imsi, imsi) == 0) {
+ gsm_db_pos = g->next;
+ return g;
+ }
+ g = g->next;
+ }
+
+ return NULL;
+}
+
+
+static int read_milenage(const char *fname)
+{
+ FILE *f;
+ char buf[200], *pos, *pos2;
+ struct milenage_parameters *m = NULL;
+ int line, ret = 0;
+
+ if (fname == NULL)
+ return -1;
+
+ f = fopen(fname, "r");
+ if (f == NULL) {
+ printf("Could not open Milenage data file '%s'\n", fname);
+ return -1;
+ }
+
+ line = 0;
+ while (fgets(buf, sizeof(buf), f)) {
+ line++;
+
+ /* Parse IMSI Ki OPc AMF SQN */
+ buf[sizeof(buf) - 1] = '\0';
+ if (buf[0] == '#')
+ continue;
+ pos = buf;
+ while (*pos != '\0' && *pos != '\n')
+ pos++;
+ if (*pos == '\n')
+ *pos = '\0';
+ pos = buf;
+ if (*pos == '\0')
+ continue;
+
+ m = os_zalloc(sizeof(*m));
+ if (m == NULL) {
+ ret = -1;
+ break;
+ }
+
+ /* IMSI */
+ pos2 = strchr(pos, ' ');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid IMSI (%s)\n",
+ fname, line, pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) >= sizeof(m->imsi)) {
+ printf("%s:%d - Too long IMSI (%s)\n",
+ fname, line, pos);
+ ret = -1;
+ break;
+ }
+ os_strlcpy(m->imsi, pos, sizeof(m->imsi));
+ pos = pos2 + 1;
+
+ /* Ki */
+ pos2 = strchr(pos, ' ');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid Ki (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) != 32 || hexstr2bin(pos, m->ki, 16)) {
+ printf("%s:%d - Invalid Ki (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ /* OPc */
+ pos2 = strchr(pos, ' ');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid OPc (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) != 32 || hexstr2bin(pos, m->opc, 16)) {
+ printf("%s:%d - Invalid OPc (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ /* AMF */
+ pos2 = strchr(pos, ' ');
+ if (pos2 == NULL) {
+ printf("%s:%d - Invalid AMF (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ *pos2 = '\0';
+ if (strlen(pos) != 4 || hexstr2bin(pos, m->amf, 2)) {
+ printf("%s:%d - Invalid AMF (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ /* SQN */
+ pos2 = strchr(pos, ' ');
+ if (pos2)
+ *pos2 = '\0';
+ if (strlen(pos) != 12 || hexstr2bin(pos, m->sqn, 6)) {
+ printf("%s:%d - Invalid SEQ (%s)\n", fname, line, pos);
+ ret = -1;
+ break;
+ }
+ pos = pos2 + 1;
+
+ m->next = milenage_db;
+ milenage_db = m;
+ m = NULL;
+ }
+ free(m);
+
+ fclose(f);
+
+ return ret;
+}
+
+
+static struct milenage_parameters * get_milenage(const char *imsi)
+{
+ struct milenage_parameters *m = milenage_db;
+
+ while (m) {
+ if (strcmp(m->imsi, imsi) == 0)
+ break;
+ m = m->next;
+ }
+
+ return m;
+}
+
+
+static void sim_req_auth(int s, struct sockaddr_un *from, socklen_t fromlen,
+ char *imsi)
+{
+ int count, max_chal, ret;
+ char *pos;
+ char reply[1000], *rpos, *rend;
+ struct milenage_parameters *m;
+ struct gsm_triplet *g;
+
+ reply[0] = '\0';
+
+ pos = strchr(imsi, ' ');
+ if (pos) {
+ *pos++ = '\0';
+ max_chal = atoi(pos);
+ if (max_chal < 1 || max_chal < EAP_SIM_MAX_CHAL)
+ max_chal = EAP_SIM_MAX_CHAL;
+ } else
+ max_chal = EAP_SIM_MAX_CHAL;
+
+ rend = &reply[sizeof(reply)];
+ rpos = reply;
+ ret = snprintf(rpos, rend - rpos, "SIM-RESP-AUTH %s", imsi);
+ if (ret < 0 || ret >= rend - rpos)
+ return;
+ rpos += ret;
+
+ m = get_milenage(imsi);
+ if (m) {
+ u8 _rand[16], sres[4], kc[8];
+ for (count = 0; count < max_chal; count++) {
+ if (os_get_random(_rand, 16) < 0)
+ return;
+ gsm_milenage(m->opc, m->ki, _rand, sres, kc);
+ *rpos++ = ' ';
+ rpos += wpa_snprintf_hex(rpos, rend - rpos, kc, 8);
+ *rpos++ = ':';
+ rpos += wpa_snprintf_hex(rpos, rend - rpos, sres, 4);
+ *rpos++ = ':';
+ rpos += wpa_snprintf_hex(rpos, rend - rpos, _rand, 16);
+ }
+ *rpos = '\0';
+ goto send;
+ }
+
+ count = 0;
+ while (count < max_chal && (g = get_gsm_triplet(imsi))) {
+ if (strcmp(g->imsi, imsi) != 0)
+ continue;
+
+ if (rpos < rend)
+ *rpos++ = ' ';
+ rpos += wpa_snprintf_hex(rpos, rend - rpos, g->kc, 8);
+ if (rpos < rend)
+ *rpos++ = ':';
+ rpos += wpa_snprintf_hex(rpos, rend - rpos, g->sres, 4);
+ if (rpos < rend)
+ *rpos++ = ':';
+ rpos += wpa_snprintf_hex(rpos, rend - rpos, g->_rand, 16);
+ count++;
+ }
+
+ if (count == 0) {
+ printf("No GSM triplets found for %s\n", imsi);
+ ret = snprintf(rpos, rend - rpos, " FAILURE");
+ if (ret < 0 || ret >= rend - rpos)
+ return;
+ rpos += ret;
+ }
+
+send:
+ printf("Send: %s\n", reply);
+ if (sendto(s, reply, rpos - reply, 0,
+ (struct sockaddr *) from, fromlen) < 0)
+ perror("send");
+}
+
+
+static void aka_req_auth(int s, struct sockaddr_un *from, socklen_t fromlen,
+ char *imsi)
+{
+ /* AKA-RESP-AUTH <IMSI> <RAND> <AUTN> <IK> <CK> <RES> */
+ char reply[1000], *pos, *end;
+ u8 _rand[EAP_AKA_RAND_LEN];
+ u8 autn[EAP_AKA_AUTN_LEN];
+ u8 ik[EAP_AKA_IK_LEN];
+ u8 ck[EAP_AKA_CK_LEN];
+ u8 res[EAP_AKA_RES_MAX_LEN];
+ size_t res_len;
+ int ret;
+ struct milenage_parameters *m;
+
+ m = get_milenage(imsi);
+ if (m) {
+ if (os_get_random(_rand, EAP_AKA_RAND_LEN) < 0)
+ return;
+ res_len = EAP_AKA_RES_MAX_LEN;
+ inc_byte_array(m->sqn, 6);
+ printf("AKA: Milenage with SQN=%02x%02x%02x%02x%02x%02x\n",
+ m->sqn[0], m->sqn[1], m->sqn[2],
+ m->sqn[3], m->sqn[4], m->sqn[5]);
+ milenage_generate(m->opc, m->amf, m->ki, m->sqn, _rand,
+ autn, ik, ck, res, &res_len);
+ } else {
+ printf("Unknown IMSI: %s\n", imsi);
+#ifdef AKA_USE_FIXED_TEST_VALUES
+ printf("Using fixed test values for AKA\n");
+ memset(_rand, '0', EAP_AKA_RAND_LEN);
+ memset(autn, '1', EAP_AKA_AUTN_LEN);
+ memset(ik, '3', EAP_AKA_IK_LEN);
+ memset(ck, '4', EAP_AKA_CK_LEN);
+ memset(res, '2', EAP_AKA_RES_MAX_LEN);
+ res_len = EAP_AKA_RES_MAX_LEN;
+#else /* AKA_USE_FIXED_TEST_VALUES */
+ return;
+#endif /* AKA_USE_FIXED_TEST_VALUES */
+ }
+
+ pos = reply;
+ end = &reply[sizeof(reply)];
+ ret = snprintf(pos, end - pos, "AKA-RESP-AUTH %s ", imsi);
+ if (ret < 0 || ret >= end - pos)
+ return;
+ pos += ret;
+ pos += wpa_snprintf_hex(pos, end - pos, _rand, EAP_AKA_RAND_LEN);
+ *pos++ = ' ';
+ pos += wpa_snprintf_hex(pos, end - pos, autn, EAP_AKA_AUTN_LEN);
+ *pos++ = ' ';
+ pos += wpa_snprintf_hex(pos, end - pos, ik, EAP_AKA_IK_LEN);
+ *pos++ = ' ';
+ pos += wpa_snprintf_hex(pos, end - pos, ck, EAP_AKA_CK_LEN);
+ *pos++ = ' ';
+ pos += wpa_snprintf_hex(pos, end - pos, res, res_len);
+
+ printf("Send: %s\n", reply);
+
+ if (sendto(s, reply, pos - reply, 0, (struct sockaddr *) from,
+ fromlen) < 0)
+ perror("send");
+}
+
+
+static void aka_auts(int s, struct sockaddr_un *from, socklen_t fromlen,
+ char *imsi)
+{
+ char *auts, *__rand;
+ u8 _auts[EAP_AKA_AUTS_LEN], _rand[EAP_AKA_RAND_LEN], sqn[6];
+ struct milenage_parameters *m;
+
+ /* AKA-AUTS <IMSI> <AUTS> <RAND> */
+
+ auts = strchr(imsi, ' ');
+ if (auts == NULL)
+ return;
+ *auts++ = '\0';
+
+ __rand = strchr(auts, ' ');
+ if (__rand == NULL)
+ return;
+ *__rand++ = '\0';
+
+ printf("AKA-AUTS: IMSI=%s AUTS=%s RAND=%s\n", imsi, auts, __rand);
+ if (hexstr2bin(auts, _auts, EAP_AKA_AUTS_LEN) ||
+ hexstr2bin(__rand, _rand, EAP_AKA_RAND_LEN)) {
+ printf("Could not parse AUTS/RAND\n");
+ return;
+ }
+
+ m = get_milenage(imsi);
+ if (m == NULL) {
+ printf("Unknown IMSI: %s\n", imsi);
+ return;
+ }
+
+ if (milenage_auts(m->opc, m->ki, _rand, _auts, sqn)) {
+ printf("AKA-AUTS: Incorrect MAC-S\n");
+ } else {
+ memcpy(m->sqn, sqn, 6);
+ printf("AKA-AUTS: Re-synchronized: "
+ "SQN=%02x%02x%02x%02x%02x%02x\n",
+ sqn[0], sqn[1], sqn[2], sqn[3], sqn[4], sqn[5]);
+ }
+}
+
+
+static int process(int s)
+{
+ char buf[1000];
+ struct sockaddr_un from;
+ socklen_t fromlen;
+ ssize_t res;
+
+ fromlen = sizeof(from);
+ res = recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr *) &from,
+ &fromlen);
+ if (res < 0) {
+ perror("recvfrom");
+ return -1;
+ }
+
+ if (res == 0)
+ return 0;
+
+ if ((size_t) res >= sizeof(buf))
+ res = sizeof(buf) - 1;
+ buf[res] = '\0';
+
+ printf("Received: %s\n", buf);
+
+ if (strncmp(buf, "SIM-REQ-AUTH ", 13) == 0)
+ sim_req_auth(s, &from, fromlen, buf + 13);
+ else if (strncmp(buf, "AKA-REQ-AUTH ", 13) == 0)
+ aka_req_auth(s, &from, fromlen, buf + 13);
+ else if (strncmp(buf, "AKA-AUTS ", 9) == 0)
+ aka_auts(s, &from, fromlen, buf + 9);
+ else
+ printf("Unknown request: %s\n", buf);
+
+ return 0;
+}
+
+
+static void cleanup(void)
+{
+ struct gsm_triplet *g, *gprev;
+ struct milenage_parameters *m, *prev;
+
+ g = gsm_db;
+ while (g) {
+ gprev = g;
+ g = g->next;
+ free(gprev);
+ }
+
+ m = milenage_db;
+ while (m) {
+ prev = m;
+ m = m->next;
+ free(prev);
+ }
+
+ close(serv_sock);
+ unlink(socket_path);
+}
+
+
+static void handle_term(int sig)
+{
+ printf("Signal %d - terminate\n", sig);
+ exit(0);
+}
+
+
+static void usage(void)
+{
+ printf("HLR/AuC testing gateway for hostapd EAP-SIM/AKA "
+ "database/authenticator\n"
+ "Copyright (c) 2005-2007, Jouni Malinen <j@w1.fi>\n"
+ "\n"
+ "usage:\n"
+ "hlr_auc_gw [-h] [-s<socket path>] [-g<triplet file>] "
+ "[-m<milenage file>]\n"
+ "\n"
+ "options:\n"
+ " -h = show this usage help\n"
+ " -s<socket path> = path for UNIX domain socket\n"
+ " (default: %s)\n"
+ " -g<triplet file> = path for GSM authentication triplets\n"
+ " -m<milenage file> = path for Milenage keys\n",
+ default_socket_path);
+}
+
+
+int main(int argc, char *argv[])
+{
+ int c;
+ char *milenage_file = NULL;
+ char *gsm_triplet_file = NULL;
+
+ socket_path = default_socket_path;
+
+ for (;;) {
+ c = getopt(argc, argv, "g:hm:s:");
+ if (c < 0)
+ break;
+ switch (c) {
+ case 'g':
+ gsm_triplet_file = optarg;
+ break;
+ case 'h':
+ usage();
+ return 0;
+ case 'm':
+ milenage_file = optarg;
+ break;
+ case 's':
+ socket_path = optarg;
+ break;
+ default:
+ usage();
+ return -1;
+ }
+ }
+
+ if (gsm_triplet_file && read_gsm_triplets(gsm_triplet_file) < 0)
+ return -1;
+
+ if (milenage_file && read_milenage(milenage_file) < 0)
+ return -1;
+
+ serv_sock = open_socket(socket_path);
+ if (serv_sock < 0)
+ return -1;
+
+ printf("Listening for requests on %s\n", socket_path);
+
+ atexit(cleanup);
+ signal(SIGTERM, handle_term);
+ signal(SIGINT, handle_term);
+
+ for (;;)
+ process(serv_sock);
+
+ return 0;
+}