RxRPC: Allow key payloads to be passed in XDR form
Allow add_key() and KEYCTL_INSTANTIATE to accept key payloads in XDR form as
described by openafs-1.4.10/src/auth/afs_token.xg. This provides a way of
passing kaserver, Kerberos 4, Kerberos 5 and GSSAPI keys from userspace, and
allows for future expansion.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/rxrpc/ar-key.c b/net/rxrpc/ar-key.c
index b3d10e7..a3a7acb 100644
--- a/net/rxrpc/ar-key.c
+++ b/net/rxrpc/ar-key.c
@@ -17,6 +17,7 @@
#include <linux/skbuff.h>
#include <linux/key-type.h>
#include <linux/crypto.h>
+#include <linux/ctype.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <keys/rxrpc-type.h>
@@ -55,6 +56,202 @@
};
/*
+ * parse an RxKAD type XDR format token
+ * - the caller guarantees we have at least 4 words
+ */
+static int rxrpc_instantiate_xdr_rxkad(struct key *key, const __be32 *xdr,
+ unsigned toklen)
+{
+ struct rxrpc_key_token *token;
+ size_t plen;
+ u32 tktlen;
+ int ret;
+
+ _enter(",{%x,%x,%x,%x},%u",
+ ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
+ toklen);
+
+ if (toklen <= 8 * 4)
+ return -EKEYREJECTED;
+ tktlen = ntohl(xdr[7]);
+ _debug("tktlen: %x", tktlen);
+ if (tktlen > AFSTOKEN_RK_TIX_MAX)
+ return -EKEYREJECTED;
+ if (8 * 4 + tktlen != toklen)
+ return -EKEYREJECTED;
+
+ plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
+ ret = key_payload_reserve(key, key->datalen + plen);
+ if (ret < 0)
+ return ret;
+
+ plen -= sizeof(*token);
+ token = kmalloc(sizeof(*token), GFP_KERNEL);
+ if (!token)
+ return -ENOMEM;
+
+ token->kad = kmalloc(plen, GFP_KERNEL);
+ if (!token->kad) {
+ kfree(token);
+ return -ENOMEM;
+ }
+
+ token->security_index = RXRPC_SECURITY_RXKAD;
+ token->kad->ticket_len = tktlen;
+ token->kad->vice_id = ntohl(xdr[0]);
+ token->kad->kvno = ntohl(xdr[1]);
+ token->kad->start = ntohl(xdr[4]);
+ token->kad->expiry = ntohl(xdr[5]);
+ token->kad->primary_flag = ntohl(xdr[6]);
+ memcpy(&token->kad->session_key, &xdr[2], 8);
+ memcpy(&token->kad->ticket, &xdr[8], tktlen);
+
+ _debug("SCIX: %u", token->security_index);
+ _debug("TLEN: %u", token->kad->ticket_len);
+ _debug("EXPY: %x", token->kad->expiry);
+ _debug("KVNO: %u", token->kad->kvno);
+ _debug("PRIM: %u", token->kad->primary_flag);
+ _debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
+ token->kad->session_key[0], token->kad->session_key[1],
+ token->kad->session_key[2], token->kad->session_key[3],
+ token->kad->session_key[4], token->kad->session_key[5],
+ token->kad->session_key[6], token->kad->session_key[7]);
+ if (token->kad->ticket_len >= 8)
+ _debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
+ token->kad->ticket[0], token->kad->ticket[1],
+ token->kad->ticket[2], token->kad->ticket[3],
+ token->kad->ticket[4], token->kad->ticket[5],
+ token->kad->ticket[6], token->kad->ticket[7]);
+
+ /* count the number of tokens attached */
+ key->type_data.x[0]++;
+
+ /* attach the data */
+ token->next = key->payload.data;
+ key->payload.data = token;
+ if (token->kad->expiry < key->expiry)
+ key->expiry = token->kad->expiry;
+
+ _leave(" = 0");
+ return 0;
+}
+
+/*
+ * attempt to parse the data as the XDR format
+ * - the caller guarantees we have more than 7 words
+ */
+static int rxrpc_instantiate_xdr(struct key *key, const void *data, size_t datalen)
+{
+ const __be32 *xdr = data, *token;
+ const char *cp;
+ unsigned len, tmp, loop, ntoken, toklen, sec_ix;
+ int ret;
+
+ _enter(",{%x,%x,%x,%x},%zu",
+ ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
+ datalen);
+
+ if (datalen > AFSTOKEN_LENGTH_MAX)
+ goto not_xdr;
+
+ /* XDR is an array of __be32's */
+ if (datalen & 3)
+ goto not_xdr;
+
+ /* the flags should be 0 (the setpag bit must be handled by
+ * userspace) */
+ if (ntohl(*xdr++) != 0)
+ goto not_xdr;
+ datalen -= 4;
+
+ /* check the cell name */
+ len = ntohl(*xdr++);
+ if (len < 1 || len > AFSTOKEN_CELL_MAX)
+ goto not_xdr;
+ datalen -= 4;
+ tmp = (len + 3) & ~3;
+ if (tmp > datalen)
+ goto not_xdr;
+
+ cp = (const char *) xdr;
+ for (loop = 0; loop < len; loop++)
+ if (!isprint(cp[loop]))
+ goto not_xdr;
+ if (len < tmp)
+ for (; loop < tmp; loop++)
+ if (cp[loop])
+ goto not_xdr;
+ _debug("cellname: [%u/%u] '%*.*s'",
+ len, tmp, len, len, (const char *) xdr);
+ datalen -= tmp;
+ xdr += tmp >> 2;
+
+ /* get the token count */
+ if (datalen < 12)
+ goto not_xdr;
+ ntoken = ntohl(*xdr++);
+ datalen -= 4;
+ _debug("ntoken: %x", ntoken);
+ if (ntoken < 1 || ntoken > AFSTOKEN_MAX)
+ goto not_xdr;
+
+ /* check each token wrapper */
+ token = xdr;
+ loop = ntoken;
+ do {
+ if (datalen < 8)
+ goto not_xdr;
+ toklen = ntohl(*xdr++);
+ sec_ix = ntohl(*xdr);
+ datalen -= 4;
+ _debug("token: [%x/%zx] %x", toklen, datalen, sec_ix);
+ if (toklen < 20 || toklen > datalen)
+ goto not_xdr;
+ datalen -= (toklen + 3) & ~3;
+ xdr += (toklen + 3) >> 2;
+
+ } while (--loop > 0);
+
+ _debug("remainder: %zu", datalen);
+ if (datalen != 0)
+ goto not_xdr;
+
+ /* okay: we're going to assume it's valid XDR format
+ * - we ignore the cellname, relying on the key to be correctly named
+ */
+ do {
+ xdr = token;
+ toklen = ntohl(*xdr++);
+ token = xdr + ((toklen + 3) >> 2);
+ sec_ix = ntohl(*xdr++);
+ toklen -= 4;
+
+ switch (sec_ix) {
+ case RXRPC_SECURITY_RXKAD:
+ ret = rxrpc_instantiate_xdr_rxkad(key, xdr, toklen);
+ if (ret != 0)
+ goto error;
+ break;
+
+ default:
+ ret = -EPROTONOSUPPORT;
+ goto error;
+ }
+
+ } while (--ntoken > 0);
+
+ _leave(" = 0");
+ return 0;
+
+not_xdr:
+ _leave(" = -EPROTO");
+ return -EPROTO;
+error:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
* instantiate an rxrpc defined key
* data should be of the form:
* OFFSET LEN CONTENT
@@ -70,8 +267,8 @@
*/
static int rxrpc_instantiate(struct key *key, const void *data, size_t datalen)
{
- const struct rxkad_key *tsec;
- struct rxrpc_key_payload *upayload;
+ const struct rxrpc_key_data_v1 *v1;
+ struct rxrpc_key_token *token, **pp;
size_t plen;
u32 kver;
int ret;
@@ -82,6 +279,13 @@
if (!data && datalen == 0)
return 0;
+ /* determine if the XDR payload format is being used */
+ if (datalen > 7 * 4) {
+ ret = rxrpc_instantiate_xdr(key, data, datalen);
+ if (ret != -EPROTO)
+ return ret;
+ }
+
/* get the key interface version number */
ret = -EINVAL;
if (datalen <= 4 || !data)
@@ -98,53 +302,67 @@
/* deal with a version 1 key */
ret = -EINVAL;
- if (datalen < sizeof(*tsec))
+ if (datalen < sizeof(*v1))
goto error;
- tsec = data;
- if (datalen != sizeof(*tsec) + tsec->ticket_len)
+ v1 = data;
+ if (datalen != sizeof(*v1) + v1->ticket_length)
goto error;
- _debug("SCIX: %u", tsec->security_index);
- _debug("TLEN: %u", tsec->ticket_len);
- _debug("EXPY: %x", tsec->expiry);
- _debug("KVNO: %u", tsec->kvno);
+ _debug("SCIX: %u", v1->security_index);
+ _debug("TLEN: %u", v1->ticket_length);
+ _debug("EXPY: %x", v1->expiry);
+ _debug("KVNO: %u", v1->kvno);
_debug("SKEY: %02x%02x%02x%02x%02x%02x%02x%02x",
- tsec->session_key[0], tsec->session_key[1],
- tsec->session_key[2], tsec->session_key[3],
- tsec->session_key[4], tsec->session_key[5],
- tsec->session_key[6], tsec->session_key[7]);
- if (tsec->ticket_len >= 8)
+ v1->session_key[0], v1->session_key[1],
+ v1->session_key[2], v1->session_key[3],
+ v1->session_key[4], v1->session_key[5],
+ v1->session_key[6], v1->session_key[7]);
+ if (v1->ticket_length >= 8)
_debug("TCKT: %02x%02x%02x%02x%02x%02x%02x%02x",
- tsec->ticket[0], tsec->ticket[1],
- tsec->ticket[2], tsec->ticket[3],
- tsec->ticket[4], tsec->ticket[5],
- tsec->ticket[6], tsec->ticket[7]);
+ v1->ticket[0], v1->ticket[1],
+ v1->ticket[2], v1->ticket[3],
+ v1->ticket[4], v1->ticket[5],
+ v1->ticket[6], v1->ticket[7]);
ret = -EPROTONOSUPPORT;
- if (tsec->security_index != RXRPC_SECURITY_RXKAD)
+ if (v1->security_index != RXRPC_SECURITY_RXKAD)
goto error;
- key->type_data.x[0] = tsec->security_index;
-
- plen = sizeof(*upayload) + tsec->ticket_len;
- ret = key_payload_reserve(key, plen);
+ plen = sizeof(*token->kad) + v1->ticket_length;
+ ret = key_payload_reserve(key, plen + sizeof(*token));
if (ret < 0)
goto error;
ret = -ENOMEM;
- upayload = kmalloc(plen, GFP_KERNEL);
- if (!upayload)
+ token = kmalloc(sizeof(*token), GFP_KERNEL);
+ if (!token)
goto error;
+ token->kad = kmalloc(plen, GFP_KERNEL);
+ if (!token->kad)
+ goto error_free;
+
+ token->security_index = RXRPC_SECURITY_RXKAD;
+ token->kad->ticket_len = v1->ticket_length;
+ token->kad->expiry = v1->expiry;
+ token->kad->kvno = v1->kvno;
+ memcpy(&token->kad->session_key, &v1->session_key, 8);
+ memcpy(&token->kad->ticket, v1->ticket, v1->ticket_length);
/* attach the data */
- memcpy(&upayload->k, tsec, sizeof(*tsec));
- memcpy(&upayload->k.ticket, (void *)tsec + sizeof(*tsec),
- tsec->ticket_len);
- key->payload.data = upayload;
- key->expiry = tsec->expiry;
+ key->type_data.x[0]++;
+
+ pp = (struct rxrpc_key_token **)&key->payload.data;
+ while (*pp)
+ pp = &(*pp)->next;
+ *pp = token;
+ if (token->kad->expiry < key->expiry)
+ key->expiry = token->kad->expiry;
+ token = NULL;
ret = 0;
+error_free:
+ kfree(token);
error:
return ret;
}
@@ -184,7 +402,22 @@
*/
static void rxrpc_destroy(struct key *key)
{
- kfree(key->payload.data);
+ struct rxrpc_key_token *token;
+
+ while ((token = key->payload.data)) {
+ key->payload.data = token->next;
+ switch (token->security_index) {
+ case RXRPC_SECURITY_RXKAD:
+ kfree(token->kad);
+ break;
+ default:
+ printk(KERN_ERR "Unknown token type %x on rxrpc key\n",
+ token->security_index);
+ BUG();
+ }
+
+ kfree(token);
+ }
}
/*
@@ -293,7 +526,7 @@
struct {
u32 kver;
- struct rxkad_key tsec;
+ struct rxrpc_key_data_v1 v1;
} data;
_enter("");
@@ -308,13 +541,12 @@
_debug("key %d", key_serial(key));
data.kver = 1;
- data.tsec.security_index = RXRPC_SECURITY_RXKAD;
- data.tsec.ticket_len = 0;
- data.tsec.expiry = expiry;
- data.tsec.kvno = 0;
+ data.v1.security_index = RXRPC_SECURITY_RXKAD;
+ data.v1.ticket_length = 0;
+ data.v1.expiry = expiry;
+ data.v1.kvno = 0;
- memcpy(&data.tsec.session_key, session_key,
- sizeof(data.tsec.session_key));
+ memcpy(&data.v1.session_key, session_key, sizeof(data.v1.session_key));
ret = key_instantiate_and_link(key, &data, sizeof(data), NULL, NULL);
if (ret < 0)