diff options
Diffstat (limited to 'src/charon/plugins/eap_sim/eap_sim_file.c')
| -rw-r--r-- | src/charon/plugins/eap_sim/eap_sim_file.c | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/src/charon/plugins/eap_sim/eap_sim_file.c b/src/charon/plugins/eap_sim/eap_sim_file.c new file mode 100644 index 000000000..7040a5ace --- /dev/null +++ b/src/charon/plugins/eap_sim/eap_sim_file.c @@ -0,0 +1,283 @@ +/*
+ * Copyright (C) 2007 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details. + * + * $Id$ + */
+
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+
+#include <daemon.h>
+
+#define IMSI_LEN 64
+#define RAND_LEN 16
+#define SRES_LEN 4
+#define KC_LEN 8
+
+typedef struct triplet_t triplet_t;
+
+struct triplet_t {
+ unsigned char imsi[IMSI_LEN];
+ unsigned char rand[RAND_LEN];
+ unsigned char sres[SRES_LEN];
+ unsigned char kc[KC_LEN];
+};
+
+static triplet_t *triplets = NULL;
+static int triplet_count = 0;
+
+#define TRIPLET_FILE IPSEC_CONFDIR "/ipsec.d/triplets.dat"
+
+/**
+ * convert a single HEX char to its integer value
+ */
+static int hexchr(char chr)
+{
+ switch (chr)
+ {
+ case '0'...'9':
+ return chr - '0';
+ case 'A'...'F':
+ return 10 + chr - 'A';
+ case 'a'...'f':
+ return 10 + chr - 'a';
+ }
+ return 0;
+}
+
+/**
+ * convert a HEX string into a char array bin, limited by array length len
+ */
+static void hex2bin(char *hex, unsigned char *bin, size_t len)
+{
+ char *pos;
+ int i, even = 1;
+
+ pos = hex - 1;
+ /* find the end, as we convert bottom up */
+ while (TRUE)
+ {
+ switch (*(pos+1))
+ {
+ case '0'...'9':
+ case 'A'...'F':
+ case 'a'...'f':
+ pos++;
+ continue;
+ }
+ break;
+ }
+ /* convert two hex chars into a single bin byte */
+ for (i = 0; pos >= hex && i < len; pos--)
+ {
+ if (even)
+ {
+ bin[len - 1 - i] = hexchr(*pos);
+ }
+ else
+ {
+ bin[len - 1 - i] |= 16 * hexchr(*pos);
+ i++;
+ }
+ even = !even;
+ }
+}
+
+/**
+ * free up allocated triplets
+ */
+static void __attribute__ ((destructor)) free_triplets()
+{
+ free(triplets);
+}
+
+/**
+ * read the triplets from the file, using freeradius triplet file syntax:
+ * http://www.freeradius.org/radiusd/doc/rlm_sim_triplets
+ */
+static void __attribute__ ((constructor)) read_triplets()
+{
+ char line[512], *data[4], *pos;
+ FILE *file;
+ int i, nr = 0;
+ triplet_t *triplet;
+
+ file = fopen(TRIPLET_FILE, "r");
+ if (file == NULL)
+ {
+ DBG1(DBG_CFG, "opening triplet file %s failed: %s",
+ TRIPLET_FILE, strerror(errno));
+ return;
+ }
+
+ if (triplets)
+ {
+ free(triplets);
+ triplets = NULL;
+ triplet_count = 0;
+ }
+
+ /* read line by line */
+ while (fgets(line, sizeof(line), file))
+ {
+ nr++;
+ /* skip comments, empty lines */
+ switch (line[0])
+ {
+ case '\n':
+ case '\r':
+ case '#':
+ case '\0':
+ continue;
+ default:
+ break;
+ }
+ /* read comma separated values */
+ pos = line;
+ for (i = 0; i < 4; i++)
+ {
+ data[i] = pos;
+ pos = strchr(pos, ',');
+ if (pos)
+ {
+ *pos = '\0';
+ pos++;
+ }
+ else if (i != 3)
+ {
+ DBG1(DBG_CFG, "error in triplet file, line %d", nr);
+ fclose(file);
+ return;
+ }
+ }
+ /* allocate new triplet */
+ triplet_count++;
+ triplets = realloc(triplets, triplet_count * sizeof(triplet_t));
+ triplet = &triplets[triplet_count - 1];
+ memset(triplet, 0, sizeof(triplet_t));
+
+ /* convert/copy triplet data */
+ for (i = 0; i < IMSI_LEN - 1; i++)
+ {
+ switch (data[0][i])
+ {
+ case '\n':
+ case '\r':
+ case '\0':
+ break;
+ default:
+ triplet->imsi[i] = data[0][i];
+ continue;
+ }
+ break;
+ }
+ hex2bin(data[1], triplet->rand, RAND_LEN);
+ hex2bin(data[2], triplet->sres, SRES_LEN);
+ hex2bin(data[3], triplet->kc, KC_LEN);
+
+ DBG4(DBG_CFG, "triplet: imsi %b\nrand %b\nsres %b\nkc %b",
+ triplet->imsi, IMSI_LEN, triplet->rand, RAND_LEN,
+ triplet->sres, SRES_LEN, triplet->kc, KC_LEN);
+ }
+ fclose(file);
+ DBG2(DBG_CFG, "read %d triplets from %s", triplet_count, TRIPLET_FILE);
+}
+
+/**
+ * Run the sim algorithm, see eap_sim.h
+ */
+int sim_run_alg(const unsigned char *rand, int rand_length,
+ unsigned char *sres, int *sres_length,
+ unsigned char *kc, int *kc_length)
+{
+ int current;
+
+ if (rand_length != RAND_LEN ||
+ *sres_length < SRES_LEN ||
+ *kc_length < KC_LEN)
+ {
+ return 1;
+ }
+
+ for (current = 0; current < triplet_count; current++)
+ {
+ if (memcmp(triplets[current].rand, rand, RAND_LEN) == 0)
+ {
+ memcpy(sres, triplets[current].sres, SRES_LEN);
+ memcpy(kc, triplets[current].kc, KC_LEN);
+ *sres_length = SRES_LEN;
+ *kc_length = KC_LEN;
+ return 0;
+ }
+ }
+ return 2;
+}
+
+/**
+ * Get a single triplet, see_eap_sim.h
+ */
+int sim_get_triplet(char *imsi,
+ unsigned char *rand, int *rand_length,
+ unsigned char *sres, int *sres_length,
+ unsigned char *kc, int *kc_length)
+{
+ int current;
+ triplet_t *triplet;
+ static int skip = -1;
+
+ DBG2(DBG_CFG, "getting triplet for %s", imsi);
+
+ if (*rand_length < RAND_LEN ||
+ *sres_length < SRES_LEN ||
+ *kc_length < KC_LEN)
+ {
+ return 1;
+ }
+ if (triplet_count == 0)
+ {
+ return 2;
+ }
+ for (current = 0; current < triplet_count; current++)
+ {
+ triplet = &triplets[current];
+
+ if (streq(imsi, triplet->imsi))
+ {
+ /* skip triplet if already used */
+ if (skip >= current)
+ {
+ continue;
+ }
+ *rand_length = RAND_LEN;
+ *sres_length = SRES_LEN;
+ *kc_length = KC_LEN;
+ memcpy(rand, triplet->rand, RAND_LEN);
+ memcpy(sres, triplet->sres, SRES_LEN);
+ memcpy(kc, triplet->kc, KC_LEN);
+ /* remember used triplet */
+ skip = current;
+ return 0;
+ }
+ }
+ if (skip > -1)
+ {
+ /* no triplet left, reuse triplets */
+ skip = -1;
+ return sim_get_triplet(imsi, rand, rand_length,
+ sres, sres_length, kc, kc_length);
+ }
+ return 2;
+}
+
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