[patch 18/51] netlabel: Add CIPSO {set, del}attr request_sock functions

Greg KH
2009-05-14T22:48:41Z

[-- Attachment #1: netlabel-add-cipso-set-del-attr-request_sock-functions.patch --]
[-- Type: text/plain, Size: 6099 bytes --]

2.6.29-stable review patch. If anyone has any objections, please let us know.

------------------

From: Paul Moore <paul.moore@hp.com>

[NOTE: based on 389fb800ac8be2832efedd19978a2b8ced37eb61]

Add the cipso_v4_req_setattr() and cipso_v4_req_delattr() functions to set and
delete the CIPSO security attributes on a request_sock used during a incoming
connection request.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

include/net/cipso_ipv4.h | 17 ++++++
net/ipv4/cipso_ipv4.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 147 insertions(+)

--- a/include/net/cipso_ipv4.h
+++ b/include/net/cipso_ipv4.h
@@ -40,6 +40,7 @@
#include <linux/net.h>
#include <linux/skbuff.h>
#include <net/netlabel.h>
+#include <net/request_sock.h>
#include <asm/atomic.h>

/* known doi values */
@@ -215,6 +216,10 @@ int cipso_v4_sock_setattr(struct sock *s
const struct netlbl_lsm_secattr *secattr);
void cipso_v4_sock_delattr(struct sock *sk);
int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr);
+int cipso_v4_req_setattr(struct request_sock *req,
+ const struct cipso_v4_doi *doi_def,
+ const struct netlbl_lsm_secattr *secattr);
+void cipso_v4_req_delattr(struct request_sock *req);
int cipso_v4_skbuff_setattr(struct sk_buff *skb,
const struct cipso_v4_doi *doi_def,
const struct netlbl_lsm_secattr *secattr);
@@ -247,6 +252,18 @@ static inline int cipso_v4_sock_getattr(
return -ENOSYS;
}

+static inline int cipso_v4_req_setattr(struct request_sock *req,
+ const struct cipso_v4_doi *doi_def,
+ const struct netlbl_lsm_secattr *secattr)
+{
+ return -ENOSYS;
+}
+
+static inline void cipso_v4_req_delattr(struct request_sock *req)
+{
+ return;
+}
+
static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb,
const struct cipso_v4_doi *doi_def,
const struct netlbl_lsm_secattr *secattr)
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1942,6 +1942,72 @@ socket_setattr_failure:
}

/**
+ * cipso_v4_req_setattr - Add a CIPSO option to a connection request socket
+ * @req: the connection request socket
+ * @doi_def: the CIPSO DOI to use
+ * @secattr: the specific security attributes of the socket
+ *
+ * Description:
+ * Set the CIPSO option on the given socket using the DOI definition and
+ * security attributes passed to the function. Returns zero on success and
+ * negative values on failure.
+ *
+ */
+int cipso_v4_req_setattr(struct request_sock *req,
+ const struct cipso_v4_doi *doi_def,
+ const struct netlbl_lsm_secattr *secattr)
+{
+ int ret_val = -EPERM;
+ unsigned char *buf = NULL;
+ u32 buf_len;
+ u32 opt_len;
+ struct ip_options *opt = NULL;
+ struct inet_request_sock *req_inet;
+
+ /* We allocate the maximum CIPSO option size here so we are probably
+ * being a little wasteful, but it makes our life _much_ easier later
+ * on and after all we are only talking about 40 bytes. */
+ buf_len = CIPSO_V4_OPT_LEN_MAX;
+ buf = kmalloc(buf_len, GFP_ATOMIC);
+ if (buf == NULL) {
+ ret_val = -ENOMEM;
+ goto req_setattr_failure;
+ }
+
+ ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
+ if (ret_val < 0)
+ goto req_setattr_failure;
+ buf_len = ret_val;
+
+ /* We can't use ip_options_get() directly because it makes a call to
+ * ip_options_get_alloc() which allocates memory with GFP_KERNEL and
+ * we won't always have CAP_NET_RAW even though we _always_ want to
+ * set the IPOPT_CIPSO option. */
+ opt_len = (buf_len + 3) & ~3;
+ opt = kzalloc(sizeof(*opt) + opt_len, GFP_ATOMIC);
+ if (opt == NULL) {
+ ret_val = -ENOMEM;
+ goto req_setattr_failure;
+ }
+ memcpy(opt->__data, buf, buf_len);
+ opt->optlen = opt_len;
+ opt->cipso = sizeof(struct iphdr);
+ kfree(buf);
+ buf = NULL;
+
+ req_inet = inet_rsk(req);
+ opt = xchg(&req_inet->opt, opt);
+ kfree(opt);
+
+ return 0;
+
+req_setattr_failure:
+ kfree(buf);
+ kfree(opt);
+ return ret_val;
+}
+
+/**
* cipso_v4_sock_delattr - Delete the CIPSO option from a socket
* @sk: the socket
*
@@ -2016,6 +2082,70 @@ void cipso_v4_sock_delattr(struct sock *
}

/**
+ * cipso_v4_req_delattr - Delete the CIPSO option from a request socket
+ * @reg: the request socket
+ *
+ * Description:
+ * Removes the CIPSO option from a request socket, if present.
+ *
+ */
+void cipso_v4_req_delattr(struct request_sock *req)
+{
+ struct ip_options *opt;
+ struct inet_request_sock *req_inet;
+
+ req_inet = inet_rsk(req);
+ opt = req_inet->opt;
+ if (opt == NULL || opt->cipso == 0)
+ return;
+
+ if (opt->srr || opt->rr || opt->ts || opt->router_alert) {
+ u8 cipso_len;
+ u8 cipso_off;
+ unsigned char *cipso_ptr;
+ int iter;
+ int optlen_new;
+
+ cipso_off = opt->cipso - sizeof(struct iphdr);
+ cipso_ptr = &opt->__data[cipso_off];
+ cipso_len = cipso_ptr[1];
+
+ if (opt->srr > opt->cipso)
+ opt->srr -= cipso_len;
+ if (opt->rr > opt->cipso)
+ opt->rr -= cipso_len;
+ if (opt->ts > opt->cipso)
+ opt->ts -= cipso_len;
+ if (opt->router_alert > opt->cipso)
+ opt->router_alert -= cipso_len;
+ opt->cipso = 0;
+
+ memmove(cipso_ptr, cipso_ptr + cipso_len,
+ opt->optlen - cipso_off - cipso_len);
+
+ /* determining the new total option length is tricky because of
+ * the padding necessary, the only thing i can think to do at
+ * this point is walk the options one-by-one, skipping the
+ * padding at the end to determine the actual option size and
+ * from there we can determine the new total option length */
+ iter = 0;
+ optlen_new = 0;
+ while (iter < opt->optlen)
+ if (opt->__data[iter] != IPOPT_NOP) {
+ iter += opt->__data[iter + 1];
+ optlen_new = iter;
+ } else
+ iter++;
+ opt->optlen = (optlen_new + 3) & ~3;
+ } else {
+ /* only the cipso option was present on the socket so we can
+ * remove the entire option struct */
+ req_inet->opt = NULL;
+ kfree(opt);
+ }
+}
+
+/**
* cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions
* @cipso: the CIPSO v4 option
* @secattr: the security attributes