ksmbd: use oid registry functions to decode OIDs

Use look_up_OID to decode OIDs rather than
implementing functions.

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Hyunchul Lee 2021-11-23 11:10:13 +09:00 committed by Steve French
parent fc74e0a40e
commit 294277410c

View File

@ -21,101 +21,11 @@
#include "ksmbd_spnego_negtokeninit.asn1.h"
#include "ksmbd_spnego_negtokentarg.asn1.h"
#define SPNEGO_OID_LEN 7
#define NTLMSSP_OID_LEN 10
#define KRB5_OID_LEN 7
#define KRB5U2U_OID_LEN 8
#define MSKRB5_OID_LEN 7
static unsigned long SPNEGO_OID[7] = { 1, 3, 6, 1, 5, 5, 2 };
static unsigned long NTLMSSP_OID[10] = { 1, 3, 6, 1, 4, 1, 311, 2, 2, 10 };
static unsigned long KRB5_OID[7] = { 1, 2, 840, 113554, 1, 2, 2 };
static unsigned long KRB5U2U_OID[8] = { 1, 2, 840, 113554, 1, 2, 2, 3 };
static unsigned long MSKRB5_OID[7] = { 1, 2, 840, 48018, 1, 2, 2 };
static char NTLMSSP_OID_STR[NTLMSSP_OID_LEN] = { 0x2b, 0x06, 0x01, 0x04, 0x01,
0x82, 0x37, 0x02, 0x02, 0x0a };
static bool
asn1_subid_decode(const unsigned char **begin, const unsigned char *end,
unsigned long *subid)
{
const unsigned char *ptr = *begin;
unsigned char ch;
*subid = 0;
do {
if (ptr >= end)
return false;
ch = *ptr++;
*subid <<= 7;
*subid |= ch & 0x7F;
} while ((ch & 0x80) == 0x80);
*begin = ptr;
return true;
}
static bool asn1_oid_decode(const unsigned char *value, size_t vlen,
unsigned long **oid, size_t *oidlen)
{
const unsigned char *iptr = value, *end = value + vlen;
unsigned long *optr;
unsigned long subid;
vlen += 1;
if (vlen < 2 || vlen > UINT_MAX / sizeof(unsigned long))
goto fail_nullify;
*oid = kmalloc(vlen * sizeof(unsigned long), GFP_KERNEL);
if (!*oid)
return false;
optr = *oid;
if (!asn1_subid_decode(&iptr, end, &subid))
goto fail;
if (subid < 40) {
optr[0] = 0;
optr[1] = subid;
} else if (subid < 80) {
optr[0] = 1;
optr[1] = subid - 40;
} else {
optr[0] = 2;
optr[1] = subid - 80;
}
*oidlen = 2;
optr += 2;
while (iptr < end) {
if (++(*oidlen) > vlen)
goto fail;
if (!asn1_subid_decode(&iptr, end, optr++))
goto fail;
}
return true;
fail:
kfree(*oid);
fail_nullify:
*oid = NULL;
return false;
}
static bool oid_eq(unsigned long *oid1, unsigned int oid1len,
unsigned long *oid2, unsigned int oid2len)
{
if (oid1len != oid2len)
return false;
return memcmp(oid1, oid2, oid1len) == 0;
}
int
ksmbd_decode_negTokenInit(unsigned char *security_blob, int length,
struct ksmbd_conn *conn)
@ -252,26 +162,18 @@ int build_spnego_ntlmssp_auth_blob(unsigned char **pbuffer, u16 *buflen,
int ksmbd_gssapi_this_mech(void *context, size_t hdrlen, unsigned char tag,
const void *value, size_t vlen)
{
unsigned long *oid;
size_t oidlen;
int err = 0;
enum OID oid;
if (!asn1_oid_decode(value, vlen, &oid, &oidlen)) {
err = -EBADMSG;
goto out;
}
if (!oid_eq(oid, oidlen, SPNEGO_OID, SPNEGO_OID_LEN))
err = -EBADMSG;
kfree(oid);
out:
if (err) {
oid = look_up_OID(value, vlen);
if (oid != OID_spnego) {
char buf[50];
sprint_oid(value, vlen, buf, sizeof(buf));
ksmbd_debug(AUTH, "Unexpected OID: %s\n", buf);
return -EBADMSG;
}
return err;
return 0;
}
int ksmbd_neg_token_init_mech_type(void *context, size_t hdrlen,
@ -279,37 +181,31 @@ int ksmbd_neg_token_init_mech_type(void *context, size_t hdrlen,
size_t vlen)
{
struct ksmbd_conn *conn = context;
unsigned long *oid;
size_t oidlen;
enum OID oid;
int mech_type;
char buf[50];
if (!asn1_oid_decode(value, vlen, &oid, &oidlen))
goto fail;
if (oid_eq(oid, oidlen, NTLMSSP_OID, NTLMSSP_OID_LEN))
oid = look_up_OID(value, vlen);
if (oid == OID_ntlmssp) {
mech_type = KSMBD_AUTH_NTLMSSP;
else if (oid_eq(oid, oidlen, MSKRB5_OID, MSKRB5_OID_LEN))
} else if (oid == OID_mskrb5) {
mech_type = KSMBD_AUTH_MSKRB5;
else if (oid_eq(oid, oidlen, KRB5_OID, KRB5_OID_LEN))
} else if (oid == OID_krb5) {
mech_type = KSMBD_AUTH_KRB5;
else if (oid_eq(oid, oidlen, KRB5U2U_OID, KRB5U2U_OID_LEN))
} else if (oid == OID_krb5u2u) {
mech_type = KSMBD_AUTH_KRB5U2U;
else
goto fail;
} else {
char buf[50];
sprint_oid(value, vlen, buf, sizeof(buf));
ksmbd_debug(AUTH, "Unexpected OID: %s\n", buf);
return -EBADMSG;
}
conn->auth_mechs |= mech_type;
if (conn->preferred_auth_mech == 0)
conn->preferred_auth_mech = mech_type;
kfree(oid);
return 0;
fail:
kfree(oid);
sprint_oid(value, vlen, buf, sizeof(buf));
ksmbd_debug(AUTH, "Unexpected OID: %s\n", buf);
return -EBADMSG;
}
int ksmbd_neg_token_init_mech_token(void *context, size_t hdrlen,