NetLabel: add the enumerated tag to the CIPSOv4 protocol
Add support for the enumerated tag (tag type #2) to the CIPSOv4 protocol.
The enumerated tag allows for 15 categories to be specified in a CIPSO option,
where each category is an unsigned 16 bit field with a maximum value of 65534.
See Documentation/netlabel/draft-ietf-cipso-ipsecurity-01.txt for more details.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 08144f8..70858dc 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -459,6 +459,10 @@
if (iter == 0)
return -EINVAL;
break;
+ case CIPSO_V4_TAG_ENUM:
+ if (doi_def->type != CIPSO_V4_MAP_PASS)
+ return -EINVAL;
+ break;
default:
return -EINVAL;
}
@@ -940,6 +944,107 @@
return -EINVAL;
}
+/**
+ * cipso_v4_map_cat_enum_valid - Checks to see if the categories are valid
+ * @doi_def: the DOI definition
+ * @enumcat: category list
+ * @enumcat_len: length of the category list in bytes
+ *
+ * Description:
+ * Checks the given categories against the given DOI definition and returns a
+ * negative value if any of the categories do not have a valid mapping and a
+ * zero value if all of the categories are valid.
+ *
+ */
+static int cipso_v4_map_cat_enum_valid(const struct cipso_v4_doi *doi_def,
+ const unsigned char *enumcat,
+ u32 enumcat_len)
+{
+ u16 cat;
+ int cat_prev = -1;
+ u32 iter;
+
+ if (doi_def->type != CIPSO_V4_MAP_PASS || enumcat_len & 0x01)
+ return -EFAULT;
+
+ for (iter = 0; iter < enumcat_len; iter += 2) {
+ cat = ntohs(*((__be16 *)&enumcat[iter]));
+ if (cat <= cat_prev)
+ return -EFAULT;
+ cat_prev = cat;
+ }
+
+ return 0;
+}
+
+/**
+ * cipso_v4_map_cat_enum_hton - Perform a category mapping from host to network
+ * @doi_def: the DOI definition
+ * @secattr: the security attributes
+ * @net_cat: the zero'd out category list in network/CIPSO format
+ * @net_cat_len: the length of the CIPSO category list in bytes
+ *
+ * Description:
+ * Perform a label mapping to translate a local MLS category bitmap to the
+ * correct CIPSO category list using the given DOI definition. Returns the
+ * size in bytes of the network category bitmap on success, negative values
+ * otherwise.
+ *
+ */
+static int cipso_v4_map_cat_enum_hton(const struct cipso_v4_doi *doi_def,
+ const struct netlbl_lsm_secattr *secattr,
+ unsigned char *net_cat,
+ u32 net_cat_len)
+{
+ int cat = -1;
+ u32 cat_iter = 0;
+
+ for (;;) {
+ cat = netlbl_secattr_catmap_walk(secattr->mls_cat, cat + 1);
+ if (cat < 0)
+ break;
+ if ((cat_iter + 2) > net_cat_len)
+ return -ENOSPC;
+
+ *((__be16 *)&net_cat[cat_iter]) = htons(cat);
+ cat_iter += 2;
+ }
+
+ return cat_iter;
+}
+
+/**
+ * cipso_v4_map_cat_enum_ntoh - Perform a category mapping from network to host
+ * @doi_def: the DOI definition
+ * @net_cat: the category list in network/CIPSO format
+ * @net_cat_len: the length of the CIPSO bitmap in bytes
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Perform a label mapping to translate a CIPSO category list to the correct
+ * local MLS category bitmap using the given DOI definition. Returns zero on
+ * success, negative values on failure.
+ *
+ */
+static int cipso_v4_map_cat_enum_ntoh(const struct cipso_v4_doi *doi_def,
+ const unsigned char *net_cat,
+ u32 net_cat_len,
+ struct netlbl_lsm_secattr *secattr)
+{
+ int ret_val;
+ u32 iter;
+
+ for (iter = 0; iter < net_cat_len; iter += 2) {
+ ret_val = netlbl_secattr_catmap_setbit(secattr->mls_cat,
+ ntohs(*((__be16 *)&net_cat[iter])),
+ GFP_ATOMIC);
+ if (ret_val != 0)
+ return ret_val;
+ }
+
+ return 0;
+}
+
/*
* Protocol Handling Functions
*/
@@ -1068,6 +1173,99 @@
}
/**
+ * cipso_v4_gentag_enum - Generate a CIPSO enumerated tag (type #2)
+ * @doi_def: the DOI definition
+ * @secattr: the security attributes
+ * @buffer: the option buffer
+ * @buffer_len: length of buffer in bytes
+ *
+ * Description:
+ * Generate a CIPSO option using the enumerated tag, tag type #2. Returns the
+ * size of the tag on success, negative values on failure.
+ *
+ */
+static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def,
+ const struct netlbl_lsm_secattr *secattr,
+ unsigned char *buffer,
+ u32 buffer_len)
+{
+ int ret_val;
+ u32 tag_len;
+ u32 level;
+
+ if (!(secattr->flags & NETLBL_SECATTR_MLS_LVL))
+ return -EPERM;
+
+ ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level);
+ if (ret_val != 0)
+ return ret_val;
+
+ if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
+ ret_val = cipso_v4_map_cat_enum_hton(doi_def,
+ secattr,
+ &buffer[4],
+ buffer_len - 4);
+ if (ret_val < 0)
+ return ret_val;
+
+ tag_len = 4 + ret_val;
+ } else
+ tag_len = 4;
+
+ buffer[0] = 0x02;
+ buffer[1] = tag_len;
+ buffer[3] = level;
+
+ return tag_len;
+}
+
+/**
+ * cipso_v4_parsetag_enum - Parse a CIPSO enumerated tag
+ * @doi_def: the DOI definition
+ * @tag: the CIPSO tag
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Parse a CIPSO enumerated tag (tag type #2) and return the security
+ * attributes in @secattr. Return zero on success, negatives values on
+ * failure.
+ *
+ */
+static int cipso_v4_parsetag_enum(const struct cipso_v4_doi *doi_def,
+ const unsigned char *tag,
+ struct netlbl_lsm_secattr *secattr)
+{
+ int ret_val;
+ u8 tag_len = tag[1];
+ u32 level;
+
+ ret_val = cipso_v4_map_lvl_ntoh(doi_def, tag[3], &level);
+ if (ret_val != 0)
+ return ret_val;
+ secattr->mls_lvl = level;
+ secattr->flags |= NETLBL_SECATTR_MLS_LVL;
+
+ if (tag_len > 4) {
+ secattr->mls_cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
+ if (secattr->mls_cat == NULL)
+ return -ENOMEM;
+
+ ret_val = cipso_v4_map_cat_enum_ntoh(doi_def,
+ &tag[4],
+ tag_len - 4,
+ secattr);
+ if (ret_val != 0) {
+ netlbl_secattr_catmap_free(secattr->mls_cat);
+ return ret_val;
+ }
+
+ secattr->flags |= NETLBL_SECATTR_MLS_CAT;
+ }
+
+ return 0;
+}
+
+/**
* cipso_v4_validate - Validate a CIPSO option
* @option: the start of the option, on error it is set to point to the error
*
@@ -1156,6 +1354,25 @@
}
}
break;
+ case CIPSO_V4_TAG_ENUM:
+ if (tag_len < 4) {
+ err_offset = opt_iter + 1;
+ goto validate_return_locked;
+ }
+
+ if (cipso_v4_map_lvl_valid(doi_def,
+ tag[3]) < 0) {
+ err_offset = opt_iter + 3;
+ goto validate_return_locked;
+ }
+ if (tag_len > 4 &&
+ cipso_v4_map_cat_enum_valid(doi_def,
+ &tag[4],
+ tag_len - 4) < 0) {
+ err_offset = opt_iter + 4;
+ goto validate_return_locked;
+ }
+ break;
default:
err_offset = opt_iter;
goto validate_return_locked;
@@ -1269,6 +1486,12 @@
&buf[CIPSO_V4_HDR_LEN],
buf_len - CIPSO_V4_HDR_LEN);
break;
+ case CIPSO_V4_TAG_ENUM:
+ ret_val = cipso_v4_gentag_enum(doi_def,
+ secattr,
+ &buf[CIPSO_V4_HDR_LEN],
+ buf_len - CIPSO_V4_HDR_LEN);
+ break;
default:
ret_val = -EPERM;
goto socket_setattr_failure;
@@ -1365,6 +1588,11 @@
&cipso_ptr[6],
secattr);
break;
+ case CIPSO_V4_TAG_ENUM:
+ ret_val = cipso_v4_parsetag_enum(doi_def,
+ &cipso_ptr[6],
+ secattr);
+ break;
}
rcu_read_unlock();
@@ -1431,6 +1659,11 @@
&cipso_ptr[6],
secattr);
break;
+ case CIPSO_V4_TAG_ENUM:
+ ret_val = cipso_v4_parsetag_enum(doi_def,
+ &cipso_ptr[6],
+ secattr);
+ break;
}
skbuff_getattr_return: