diff options
Diffstat (limited to 'fs/cifs/cifs_spnego.c')
| -rw-r--r-- | fs/cifs/cifs_spnego.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/fs/cifs/cifs_spnego.c b/fs/cifs/cifs_spnego.c new file mode 100644 index 000000000..f4cf200b3 --- /dev/null +++ b/fs/cifs/cifs_spnego.c @@ -0,0 +1,179 @@ +/* + * fs/cifs/cifs_spnego.c -- SPNEGO upcall management for CIFS + * + * Copyright (c) 2007 Red Hat, Inc. + * Author(s): Jeff Layton (jlayton@redhat.com) + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published + * by the Free Software Foundation; either version 2.1 of the License, or + * (at your option) any later version. + * + * This library 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 Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <keys/user-type.h> +#include <linux/key-type.h> +#include <linux/inet.h> +#include "cifsglob.h" +#include "cifs_spnego.h" +#include "cifs_debug.h" + +/* create a new cifs key */ +static int +cifs_spnego_key_instantiate(struct key *key, struct key_preparsed_payload *prep) +{ + char *payload; + int ret; + + ret = -ENOMEM; + payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL); + if (!payload) + goto error; + + /* attach the data */ + key->payload.data = payload; + ret = 0; + +error: + return ret; +} + +static void +cifs_spnego_key_destroy(struct key *key) +{ + kfree(key->payload.data); +} + + +/* + * keytype for CIFS spnego keys + */ +struct key_type cifs_spnego_key_type = { + .name = "cifs.spnego", + .instantiate = cifs_spnego_key_instantiate, + .destroy = cifs_spnego_key_destroy, + .describe = user_describe, +}; + +/* length of longest version string e.g. strlen("ver=0xFF") */ +#define MAX_VER_STR_LEN 8 + +/* length of longest security mechanism name, eg in future could have + * strlen(";sec=ntlmsspi") */ +#define MAX_MECH_STR_LEN 13 + +/* strlen of "host=" */ +#define HOST_KEY_LEN 5 + +/* strlen of ";ip4=" or ";ip6=" */ +#define IP_KEY_LEN 5 + +/* strlen of ";uid=0x" */ +#define UID_KEY_LEN 7 + +/* strlen of ";creduid=0x" */ +#define CREDUID_KEY_LEN 11 + +/* strlen of ";user=" */ +#define USER_KEY_LEN 6 + +/* strlen of ";pid=0x" */ +#define PID_KEY_LEN 7 + +/* get a key struct with a SPNEGO security blob, suitable for session setup */ +struct key * +cifs_get_spnego_key(struct cifs_ses *sesInfo) +{ + struct TCP_Server_Info *server = sesInfo->server; + struct sockaddr_in *sa = (struct sockaddr_in *) &server->dstaddr; + struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) &server->dstaddr; + char *description, *dp; + size_t desc_len; + struct key *spnego_key; + const char *hostname = server->hostname; + + /* length of fields (with semicolons): ver=0xyz ip4=ipaddress + host=hostname sec=mechanism uid=0xFF user=username */ + desc_len = MAX_VER_STR_LEN + + HOST_KEY_LEN + strlen(hostname) + + IP_KEY_LEN + INET6_ADDRSTRLEN + + MAX_MECH_STR_LEN + + UID_KEY_LEN + (sizeof(uid_t) * 2) + + CREDUID_KEY_LEN + (sizeof(uid_t) * 2) + + PID_KEY_LEN + (sizeof(pid_t) * 2) + 1; + + if (sesInfo->user_name) + desc_len += USER_KEY_LEN + strlen(sesInfo->user_name); + + spnego_key = ERR_PTR(-ENOMEM); + description = kzalloc(desc_len, GFP_KERNEL); + if (description == NULL) + goto out; + + dp = description; + /* start with version and hostname portion of UNC string */ + spnego_key = ERR_PTR(-EINVAL); + sprintf(dp, "ver=0x%x;host=%s;", CIFS_SPNEGO_UPCALL_VERSION, + hostname); + dp = description + strlen(description); + + /* add the server address */ + if (server->dstaddr.ss_family == AF_INET) + sprintf(dp, "ip4=%pI4", &sa->sin_addr); + else if (server->dstaddr.ss_family == AF_INET6) + sprintf(dp, "ip6=%pI6", &sa6->sin6_addr); + else + goto out; + + dp = description + strlen(description); + + /* for now, only sec=krb5 and sec=mskrb5 are valid */ + if (server->sec_kerberos) + sprintf(dp, ";sec=krb5"); + else if (server->sec_mskerberos) + sprintf(dp, ";sec=mskrb5"); + else + goto out; + + dp = description + strlen(description); + sprintf(dp, ";uid=0x%x", + from_kuid_munged(&init_user_ns, sesInfo->linux_uid)); + + dp = description + strlen(description); + sprintf(dp, ";creduid=0x%x", + from_kuid_munged(&init_user_ns, sesInfo->cred_uid)); + + if (sesInfo->user_name) { + dp = description + strlen(description); + sprintf(dp, ";user=%s", sesInfo->user_name); + } + + dp = description + strlen(description); + sprintf(dp, ";pid=0x%x", current->pid); + + cifs_dbg(FYI, "key description = %s\n", description); + spnego_key = request_key(&cifs_spnego_key_type, description, ""); + +#ifdef CONFIG_CIFS_DEBUG2 + if (cifsFYI && !IS_ERR(spnego_key)) { + struct cifs_spnego_msg *msg = spnego_key->payload.data; + cifs_dump_mem("SPNEGO reply blob:", msg->data, min(1024U, + msg->secblob_len + msg->sesskey_len)); + } +#endif /* CONFIG_CIFS_DEBUG2 */ + +out: + kfree(description); + return spnego_key; +} |