#include "eap_aka_3gpp2_functions.h"
+#include <gmp.h>
+#include <limits.h>
+
+#include <daemon.h>
+
typedef struct private_eap_aka_3gpp2_functions_t private_eap_aka_3gpp2_functions_t;
/**
* Public eap_aka_3gpp2_functions_t interface.
*/
eap_aka_3gpp2_functions_t public;
+
+ /**
+ * Used keyed SHA1 function, as PRF
+ */
+ prf_t *prf;
+};
+
+#define PAYLOAD_LENGTH 64
+
+#define F1 0x42
+#define F1STAR 0x43
+#define F2 0x44
+#define F3 0x45
+#define F4 0x46
+#define F5 0x47
+#define F5STAR 0x48
+
+/** Family key, as proposed in S.S0055 */
+static chunk_t fmk = chunk_from_chars(0x41, 0x48, 0x41, 0x47);
+
+/**
+ * Binary represnation of the polynom T^160 + T^5 + T^3 + T^2 + 1
+ */
+static u_int8_t g[] = {
+ 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00, 0x2d
+};
+
+/**
+ * Predefined random bits from the RAND Corporation book
+ */
+static u_int8_t a[] = {
+ 0x9d, 0xe9, 0xc9, 0xc8, 0xef, 0xd5, 0x78, 0x11,
+ 0x48, 0x23, 0x14, 0x01, 0x90, 0x1f, 0x2d, 0x49,
+ 0x3f, 0x4c, 0x63, 0x65
+};
+
+/**
+ * Predefined random bits from the RAND Corporation book
+ */
+static u_int8_t b[] = {
+ 0x75, 0xef, 0xd1, 0x5c, 0x4b, 0x8f, 0x8f, 0x51,
+ 0x4e, 0xf3, 0xbc, 0xc3, 0x79, 0x4a, 0x76, 0x5e,
+ 0x7e, 0xec, 0x45, 0xe0
};
+/**
+ * Multiplicate two mpz_t with bits interpreted as polynoms.
+ */
+static void mpz_mul_poly(mpz_t r, mpz_t a, mpz_t b)
+{
+ mpz_t bm, rm;
+ int current = 0, shifted = 0, shift;
+
+ mpz_init_set(bm, b);
+ mpz_init_set_ui(rm, 0);
+ /* scan through a, for each found bit: */
+ while ((current = mpz_scan1(a, current)) != ULONG_MAX)
+ {
+ /* XOR shifted b into r */
+ shift = current - shifted;
+ mpz_mul_2exp(bm, bm, shift);
+ shifted += shift;
+ mpz_xor(rm, rm, bm);
+ current++;
+ }
+
+ mpz_swap(r, rm);
+ mpz_clear(rm);
+ mpz_clear(bm);
+}
+
+/**
+ * Calculate the sum of a + b interpreted as polynoms.
+ */
+static void mpz_add_poly(mpz_t res, mpz_t a, mpz_t b)
+{
+ /* addition of polynominals is just the XOR */
+ mpz_xor(res, a, b);
+}
+
+/**
+ * Calculate the remainder of a/b interpreted as polynoms.
+ */
+static void mpz_mod_poly(mpz_t r, mpz_t a, mpz_t b)
+{
+ /* Example:
+ * a = 10001010
+ * b = 00000101
+ */
+ int a_bit, b_bit, diff;
+ mpz_t bm, am;
+
+ mpz_init_set(am, a);
+ mpz_init(bm);
+
+ a_bit = mpz_sizeinbase(a, 2);
+ b_bit = mpz_sizeinbase(b, 2);
+
+ /* don't do anything if b > a */
+ if (a_bit >= b_bit)
+ {
+ /* shift b left to align up most signaficant "1" to a:
+ * a = 10001010
+ * b = 10100000
+ */
+ mpz_mul_2exp(bm, b, a_bit - b_bit);
+ do
+ {
+ /* XOR b into a, this kills the most significant "1":
+ * a = 00101010
+ */
+ mpz_xor(am, am, bm);
+ /* find the next most significant "1" in a, and align up b:
+ * a = 00101010
+ * b = 00101000
+ */
+ diff = a_bit - mpz_sizeinbase(am, 2);
+ mpz_div_2exp(bm, bm, diff);
+ a_bit -= diff;
+ }
+ while (b_bit <= mpz_sizeinbase(bm, 2));
+ /* While b is not shifted to its original value */
+ }
+ /* after another iteration:
+ * a = 00000010
+ * which is the polynomial modulo
+ */
+
+ mpz_swap(r, am);
+ mpz_clear(am);
+ mpz_clear(bm);
+}
+
+/**
+ * Step 3 of the various fx() functions:
+ * XOR the key into the SHA1 IV
+ */
+static void step3(prf_t *prf, u_char k[K_LENGTH], u_char payload[PAYLOAD_LENGTH],
+ u_int8_t h[HASH_SIZE_SHA1])
+{
+ /* use the keyed hasher to build the hash */
+ prf->set_key(prf, chunk_create(k, sizeof(k)));
+ prf->get_bytes(prf, chunk_create(payload, sizeof(payload)), h);
+}
+
+/**
+ * Step 4 of the various fx() functions:
+ * Polynomial whiten calculations
+ */
+static void step4(u_char x[HASH_SIZE_SHA1])
+{
+ mpz_t xm, am, bm, gm;
+
+ mpz_init(xm);
+ mpz_init(am);
+ mpz_init(bm);
+ mpz_init(gm);
+
+ mpz_import(xm, sizeof(x), 1, 1, 1, 0, x);
+ mpz_import(am, sizeof(a), 1, 1, 1, 0, a);
+ mpz_import(bm, sizeof(b), 1, 1, 1, 0, b);
+ mpz_import(gm, sizeof(g), 1, 1, 1, 0, g);
+
+ mpz_mul_poly(xm, am, xm);
+ mpz_add_poly(xm, bm, xm);
+ mpz_mod_poly(xm, xm, gm);
+
+ mpz_export(x, NULL, 1, sizeof(x), 1, 0, xm);
+
+ mpz_clear(xm);
+ mpz_clear(am);
+ mpz_clear(bm);
+ mpz_clear(gm);
+}
+
+/**
+ * Calculation function for f2(), f3(), f4()
+ */
+static void fx(prf_t *prf, u_char f, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char out[MAC_LENGTH])
+{
+ u_char payload[PAYLOAD_LENGTH];
+ u_char h[HASH_SIZE_SHA1];
+ u_char i;
+
+ for (i = 0; i < 2; i++)
+ {
+ memset(payload, 0x5c, sizeof(payload));
+ payload[11] ^= f;
+ memxor(payload + 12, fmk.ptr, fmk.len);
+ memxor(payload + 24, rand, sizeof(rand));
+
+ payload[3] ^= i;
+ payload[19] ^= i;
+ payload[35] ^= i;
+ payload[51] ^= i;
+
+ step3(prf, k, payload, h);
+ step4(h);
+ memcpy(out + i * 8, h, 8);
+ }
+}
+
+/**
+ * Calculation function of f1() and f1star()
+ */
+static void f1x(prf_t *prf, u_int8_t f, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH],
+ u_char amf[AMF_LENGTH], u_char mac[MAC_LENGTH])
+{
+ /* generate MAC = f1(FMK, SQN, RAND, AMF)
+ * K is loaded into hashers IV; FMK, RAND, SQN, AMF are XORed in a 512-bit
+ * payload which gets hashed
+ */
+ u_char payload[PAYLOAD_LENGTH];
+ u_char h[HASH_SIZE_SHA1];
+
+ memset(payload, 0x5c, sizeof(payload));
+ payload[11] ^= f;
+ memxor(payload + 12, fmk.ptr, fmk.len);
+ memxor(payload + 16, rand, sizeof(rand));
+ memxor(payload + 34, sqn, sizeof(sqn));
+ memxor(payload + 42, amf, sizeof(amf));
+
+ step3(prf, k, payload, h);
+ step4(h);
+ memcpy(mac, h, sizeof(mac));
+}
+
+/**
+ * Calculation function of f5() and f5star()
+ */
+static void f5x(prf_t *prf, u_char f, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ak[AK_LENGTH])
+{
+ u_char payload[PAYLOAD_LENGTH];
+ u_char h[HASH_SIZE_SHA1];
+
+ memset(payload, 0x5c, sizeof(payload));
+ payload[11] ^= f;
+ memxor(payload + 12, fmk.ptr, fmk.len);
+ memxor(payload + 16, rand, sizeof(rand));
+
+ step3(prf, k, payload, h);
+ step4(h);
+ memcpy(ak, h, sizeof(ak));
+}
+
+/**
+ * Calculate MAC from RAND, SQN, AMF using K
+ */
+static void f1(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH],
+ u_char amf[AMF_LENGTH], u_char mac[MAC_LENGTH])
+{
+ f1x(this->prf, F1, k, rand, sqn, amf, mac);
+ DBG3(DBG_IKE, "MAC %b", mac, sizeof(mac));
+}
+
+/**
+ * Calculate MACS from RAND, SQN, AMF using K
+ */
+static void f1star(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH],
+ u_char amf[AMF_LENGTH], u_char macs[MAC_LENGTH])
+{
+ f1x(this->prf, F1STAR, k, rand, sqn, amf, macs);
+ DBG3(DBG_IKE, "MACS %b", macs, sizeof(macs));
+}
+
+/**
+ * Calculate RES from RAND using K
+ */
+static void f2(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char res[RES_LENGTH])
+{
+ fx(this->prf, F2, k, rand, res);
+ DBG3(DBG_IKE, "RES %b", res, sizeof(res));
+}
+
+/**
+ * Calculate CK from RAND using K
+ */
+static void f3(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ck[CK_LENGTH])
+{
+ fx(this->prf, F3, k, rand, ck);
+ DBG3(DBG_IKE, "CK %b", ck, sizeof(ck));
+}
+
+/**
+ * Calculate IK from RAND using K
+ */
+static void f4(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ik[IK_LENGTH])
+{
+ fx(this->prf, F4, k, rand, ik);
+ DBG3(DBG_IKE, "IK %b", ik, sizeof(ik));
+}
+
+/**
+ * Calculate AK from a RAND using K
+ */
+static void f5(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ak[AK_LENGTH])
+{
+ f5x(this->prf, F5, k, rand, ak);
+ DBG3(DBG_IKE, "AK %b", ak, sizeof(ak));
+}
+
+/**
+ * Calculate AKS from a RAND using K
+ */
+static void f5star(private_eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char aks[AK_LENGTH])
+{
+ f5x(this->prf, F5STAR, k, rand, aks);
+ DBG3(DBG_IKE, "AKS %b", aks, sizeof(aks));
+}
+
+
/**
* Implementation of eap_aka_3gpp2_functions_t.destroy.
*/
static void destroy(private_eap_aka_3gpp2_functions_t *this)
{
+ this->prf->destroy(this->prf);
free(this);
}
*/
eap_aka_3gpp2_functions_t *eap_aka_3gpp2_functions_create()
{
- private_eap_aka_3gpp2_functions_t *this = malloc_thing(private_eap_aka_3gpp2_functions_t);
+ private_eap_aka_3gpp2_functions_t *this;
+
+ this = malloc_thing(private_eap_aka_3gpp2_functions_t);
+ this->public.f1 = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH], u_char amf[AMF_LENGTH], u_char mac[MAC_LENGTH]))f1;
+ this->public.f1star = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH], u_char amf[AMF_LENGTH], u_char macs[MAC_LENGTH]))f1star;
+ this->public.f2 = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char res[RES_LENGTH]))f2;
+ this->public.f3 = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char ck[CK_LENGTH]))f3;
+ this->public.f4 = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char ik[IK_LENGTH]))f4;
+ this->public.f5 = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char ak[AK_LENGTH]))f5;
+ this->public.f5star = (void(*)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH], u_char rand[RAND_LENGTH], u_char aks[AK_LENGTH]))f5star;
this->public.destroy = (void(*)(eap_aka_3gpp2_functions_t*))destroy;
+ this->prf = lib->crypto->create_prf(lib->crypto, PRF_KEYED_SHA1);
+ if (!this->prf)
+ {
+ DBG1(DBG_CFG, "%N not supported, unable to use 3GPP2 algorithm",
+ pseudo_random_function_names, PRF_KEYED_SHA1);
+ free(this);
+ return NULL;
+ }
return &this->public;
}
#include <utils/enumerator.h>
#include <utils/identification.h>
+#define RAND_LENGTH 16
+#define RES_LENGTH 16
+#define SQN_LENGTH 6
+#define K_LENGTH 16
+#define MAC_LENGTH 8
+#define CK_LENGTH 16
+#define IK_LENGTH 16
+#define AK_LENGTH 6
+#define AMF_LENGTH 2
+#define FMK_LENGTH 4
+#define AUTN_LENGTH (SQN_LENGTH + AMF_LENGTH + MAC_LENGTH)
+#define AUTS_LENGTH (SQN_LENGTH + MAC_LENGTH)
+
typedef struct eap_aka_3gpp2_functions_t eap_aka_3gpp2_functions_t;
/**
*/
struct eap_aka_3gpp2_functions_t {
+ /**
+ * Calculate MAC from RAND, SQN, AMF using K.
+ *
+ * @param k secret key K
+ * @param rand random value rand
+ * @param sqn sequence number
+ * @param amf authentication management field
+ * @param mac buffer receiving mac MAC
+ */
+ void (*f1)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH],
+ u_char amf[AMF_LENGTH], u_char mac[MAC_LENGTH]);
+
+ /**
+ * Calculate MACS from RAND, SQN, AMF using K
+ *
+ * @param k secret key K
+ * @param rand random value RAND
+ * @param sqn sequence number
+ * @param amf authentication management field
+ * @param macs buffer receiving resynchronization mac MACS
+ */
+ void (*f1star)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char sqn[SQN_LENGTH],
+ u_char amf[AMF_LENGTH], u_char macs[MAC_LENGTH]);
+
+ /**
+ * Calculate RES from RAND using K
+ *
+ * @param k secret key K
+ * @param rand random value RAND
+ * @param macs buffer receiving result RES
+ */
+ void (*f2)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char res[RES_LENGTH]);
+ /**
+ * Calculate CK from RAND using K
+ *
+ * @param k secret key K
+ * @param rand random value RAND
+ * @param macs buffer receiving encryption key CK
+ */
+ void (*f3)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ck[CK_LENGTH]);
+ /**
+ * Calculate IK from RAND using K
+ *
+ * @param k secret key K
+ * @param rand random value RAND
+ * @param macs buffer receiving integrity key IK
+ */
+ void (*f4)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ik[IK_LENGTH]);
+ /**
+ * Calculate AK from a RAND using K
+ *
+ * @param k secret key K
+ * @param rand random value RAND
+ * @param macs buffer receiving anonymity key AK
+ */
+ void (*f5)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char ak[AK_LENGTH]);
+ /**
+ * Calculate AKS from a RAND using K
+ *
+ * @param k secret key K
+ * @param rand random value RAND
+ * @param macs buffer receiving resynchronization anonymity key AKS
+ */
+ void (*f5star)(eap_aka_3gpp2_functions_t *this, u_char k[K_LENGTH],
+ u_char rand[RAND_LENGTH], u_char aks[AK_LENGTH]);
+
/**
* Destroy a eap_aka_3gpp2_functions_t.
*/
/**
* Create a eap_aka_3gpp2_functions instance.
+ *
+ * @return function set, NULL on error
*/
eap_aka_3gpp2_functions_t *eap_aka_3gpp2_functions_create();
projects / thirdparty / strongswan.git / commitdiff
