Refactor COMP128v23 implementation and add test suit
diff --git a/src/gsm/auth_comp128v23.c b/src/gsm/auth_comp128v23.c
index 36383d9..168f886 100644
--- a/src/gsm/auth_comp128v23.c
+++ b/src/gsm/auth_comp128v23.c
@@ -31,7 +31,7 @@
struct osmo_sub_auth_data *aud,
const uint8_t *_rand)
{
- comp128v23(aud->u.gsm.ki, _rand, 2, vec->sres, vec->kc);
+ comp128v2(aud->u.gsm.ki, _rand, vec->sres, vec->kc);
vec->auth_types = OSMO_AUTH_TYPE_GSM;
return 0;
@@ -48,7 +48,7 @@
struct osmo_sub_auth_data *aud,
const uint8_t *_rand)
{
- comp128v23(aud->u.gsm.ki, _rand, 3, vec->sres, vec->kc);
+ comp128v3(aud->u.gsm.ki, _rand, vec->sres, vec->kc);
vec->auth_types = OSMO_AUTH_TYPE_GSM;
return 0;
diff --git a/src/gsm/comp128v23.c b/src/gsm/comp128v23.c
index 9004208..e21b718 100644
--- a/src/gsm/comp128v23.c
+++ b/src/gsm/comp128v23.c
@@ -64,21 +64,17 @@
218, 160, 187, 106, 35, 87, 105, 96, 145, 199, 159, 12, 121, 103, 112
};
-#define RAND_SIZE 16
-#define KI_SIZE 16
-#define SRES_SIZE 4
-#define KC_SIZE 8
static void
_comp128v23_internal(uint8_t *output, const uint8_t *kxor, const uint8_t *rand)
{
- uint8_t temp[RAND_SIZE];
- uint8_t km_rm[RAND_SIZE+KI_SIZE];
+ uint8_t temp[16];
+ uint8_t km_rm[32];
uint8_t i,j,k,z;
- memset(temp,0,sizeof(temp)/sizeof(uint8_t));
- memcpy(km_rm,rand,RAND_SIZE);
- memcpy(km_rm+RAND_SIZE,kxor,KI_SIZE);
+ memset(temp, 0, sizeof(temp));
+ memcpy(km_rm, rand, 16);
+ memcpy(km_rm + 16, kxor, 16);
for (i=0; i<5; i++) {
for (z=0; z<16; z++) {
@@ -106,21 +102,18 @@
}
int
-comp128v23(const uint8_t *ki, const uint8_t *rand, uint8_t version, uint8_t *sres, uint8_t *kc)
+comp128v3(const uint8_t *ki, const uint8_t *rand, uint8_t *sres, uint8_t *kc)
{
- uint8_t k_mix[KI_SIZE];
- uint8_t rand_mix[RAND_SIZE];
- uint8_t katyvasz[KI_SIZE];
- uint8_t output[KI_SIZE];
- uint8_t i,s;
+ uint8_t k_mix[16];
+ uint8_t rand_mix[16];
+ uint8_t katyvasz[16];
+ uint8_t output[16];
+ uint8_t i;
- if (!(version==2 || version==3))
- return 1;
-
- memset(k_mix,0,sizeof(k_mix)/sizeof(uint8_t));
- memset(rand_mix,0,sizeof(rand_mix)/sizeof(uint8_t));
- memset(katyvasz,0,sizeof(katyvasz)/sizeof(uint8_t));
- memset(output,0,sizeof(output)/sizeof(uint8_t));
+ memset(k_mix, 0, sizeof(k_mix));
+ memset(rand_mix, 0, sizeof(rand_mix));
+ memset(katyvasz, 0, sizeof(katyvasz));
+ memset(output, 0, sizeof(output));
for (i=0; i<8; i++) {
k_mix[i] = ki[15 - i];
@@ -144,23 +137,21 @@
output[i] = rand_mix[15-i];
}
- if (version==2) {
- output[15] = 0;
- output[14] = 4*(output[14]>>2);
- }
-
- s = 8;
- i = 0;
- while (i<4) {
- output[s+i-4] = output[s+i];
- output[s+i] = output[s+i+4];
- i++;
- }
+ memmove(output + 4, output + 8, 8); /* ignore bytes 4..7 */
/* the algorithm uses 16 bytes until this point, but only 12 bytes are effective
* also 12 bytes coming out from the SIM card */
- memcpy(sres,output,SRES_SIZE*sizeof(uint8_t));
- memcpy(kc,&output[SRES_SIZE],KC_SIZE*sizeof(uint8_t));
+ memcpy(sres, output, 4);
+ memcpy(kc, output + 4, 8);
return 0;
}
+
+int
+comp128v2(const uint8_t *ki, const uint8_t *rand, uint8_t *sres, uint8_t *kc)
+{
+ int r = comp128v3(ki, rand, sres, kc);
+ kc[7] = 0; /* 10 last bits of Kc forced to 0 */
+ kc[6] &= 0xfc;
+ return r;
+}