nfsd4: don't check ip address in setclientid
[safe/jmp/linux-2.6] / net / ipv4 / cipso_ipv4.c
index e13d6db..7bc9929 100644 (file)
@@ -3,11 +3,16 @@
  *
  * This is an implementation of the CIPSO 2.2 protocol as specified in
  * draft-ietf-cipso-ipsecurity-01.txt with additional tag types as found in
- * FIPS-188, copies of both documents can be found in the Documentation
- * directory.  While CIPSO never became a full IETF RFC standard many vendors
+ * FIPS-188.  While CIPSO never became a full IETF RFC standard many vendors
  * have chosen to adopt the protocol and over the years it has become a
  * de-facto standard for labeled networking.
  *
+ * The CIPSO draft specification can be found in the kernel's Documentation
+ * directory as well as the following URL:
+ *   http://netlabel.sourceforge.net/files/draft-ietf-cipso-ipsecurity-01.txt
+ * The FIPS-188 specification can be found at the following URL:
+ *   http://www.itl.nist.gov/fipspubs/fip188.htm
+ *
  * Author: Paul Moore <paul.moore@hp.com>
  *
  */
@@ -38,6 +43,7 @@
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/jhash.h>
+#include <linux/audit.h>
 #include <net/ip.h>
 #include <net/icmp.h>
 #include <net/tcp.h>
@@ -109,6 +115,19 @@ int cipso_v4_rbm_strictvalid = 1;
  * be omitted. */
 #define CIPSO_V4_TAG_RNG_CAT_MAX      8
 
+/* Base length of the local tag (non-standard tag).
+ *  Tag definition (may change between kernel versions)
+ *
+ * 0          8          16         24         32
+ * +----------+----------+----------+----------+
+ * | 10000000 | 00000110 | 32-bit secid value  |
+ * +----------+----------+----------+----------+
+ * | in (host byte order)|
+ * +----------+----------+
+ *
+ */
+#define CIPSO_V4_TAG_LOC_BLEN         6
+
 /*
  * Helper Functions
  */
@@ -436,6 +455,7 @@ static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
 /**
  * cipso_v4_doi_add - Add a new DOI to the CIPSO protocol engine
  * @doi_def: the DOI structure
+ * @audit_info: NetLabel audit information
  *
  * Description:
  * The caller defines a new DOI for use by the CIPSO engine and calls this
@@ -445,47 +465,78 @@ static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
  * zero on success and non-zero on failure.
  *
  */
-int cipso_v4_doi_add(struct cipso_v4_doi *doi_def)
+int cipso_v4_doi_add(struct cipso_v4_doi *doi_def,
+                    struct netlbl_audit *audit_info)
 {
+       int ret_val = -EINVAL;
        u32 iter;
+       u32 doi;
+       u32 doi_type;
+       struct audit_buffer *audit_buf;
+
+       doi = doi_def->doi;
+       doi_type = doi_def->type;
 
        if (doi_def == NULL || doi_def->doi == CIPSO_V4_DOI_UNKNOWN)
-               return -EINVAL;
+               goto doi_add_return;
        for (iter = 0; iter < CIPSO_V4_TAG_MAXCNT; iter++) {
                switch (doi_def->tags[iter]) {
                case CIPSO_V4_TAG_RBITMAP:
                        break;
                case CIPSO_V4_TAG_RANGE:
+               case CIPSO_V4_TAG_ENUM:
                        if (doi_def->type != CIPSO_V4_MAP_PASS)
-                               return -EINVAL;
+                               goto doi_add_return;
+                       break;
+               case CIPSO_V4_TAG_LOCAL:
+                       if (doi_def->type != CIPSO_V4_MAP_LOCAL)
+                               goto doi_add_return;
                        break;
                case CIPSO_V4_TAG_INVALID:
                        if (iter == 0)
-                               return -EINVAL;
-                       break;
-               case CIPSO_V4_TAG_ENUM:
-                       if (doi_def->type != CIPSO_V4_MAP_PASS)
-                               return -EINVAL;
+                               goto doi_add_return;
                        break;
                default:
-                       return -EINVAL;
+                       goto doi_add_return;
                }
        }
 
        atomic_set(&doi_def->refcount, 1);
-       INIT_RCU_HEAD(&doi_def->rcu);
 
        spin_lock(&cipso_v4_doi_list_lock);
-       if (cipso_v4_doi_search(doi_def->doi) != NULL)
-               goto doi_add_failure;
+       if (cipso_v4_doi_search(doi_def->doi) != NULL) {
+               spin_unlock(&cipso_v4_doi_list_lock);
+               ret_val = -EEXIST;
+               goto doi_add_return;
+       }
        list_add_tail_rcu(&doi_def->list, &cipso_v4_doi_list);
        spin_unlock(&cipso_v4_doi_list_lock);
+       ret_val = 0;
+
+doi_add_return:
+       audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_ADD, audit_info);
+       if (audit_buf != NULL) {
+               const char *type_str;
+               switch (doi_type) {
+               case CIPSO_V4_MAP_TRANS:
+                       type_str = "trans";
+                       break;
+               case CIPSO_V4_MAP_PASS:
+                       type_str = "pass";
+                       break;
+               case CIPSO_V4_MAP_LOCAL:
+                       type_str = "local";
+                       break;
+               default:
+                       type_str = "(unknown)";
+               }
+               audit_log_format(audit_buf,
+                                " cipso_doi=%u cipso_type=%s res=%u",
+                                doi, type_str, ret_val == 0 ? 1 : 0);
+               audit_log_end(audit_buf);
+       }
 
-       return 0;
-
-doi_add_failure:
-       spin_unlock(&cipso_v4_doi_list_lock);
-       return -EEXIST;
+       return ret_val;
 }
 
 /**
@@ -502,7 +553,7 @@ void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
                return;
 
        switch (doi_def->type) {
-       case CIPSO_V4_MAP_STD:
+       case CIPSO_V4_MAP_TRANS:
                kfree(doi_def->map.std->lvl.cipso);
                kfree(doi_def->map.std->lvl.local);
                kfree(doi_def->map.std->cat.cipso);
@@ -543,25 +594,39 @@ static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
  */
 int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
 {
+       int ret_val;
        struct cipso_v4_doi *doi_def;
+       struct audit_buffer *audit_buf;
 
        spin_lock(&cipso_v4_doi_list_lock);
        doi_def = cipso_v4_doi_search(doi);
        if (doi_def == NULL) {
                spin_unlock(&cipso_v4_doi_list_lock);
-               return -ENOENT;
+               ret_val = -ENOENT;
+               goto doi_remove_return;
        }
        if (!atomic_dec_and_test(&doi_def->refcount)) {
                spin_unlock(&cipso_v4_doi_list_lock);
-               return -EBUSY;
+               ret_val = -EBUSY;
+               goto doi_remove_return;
        }
        list_del_rcu(&doi_def->list);
        spin_unlock(&cipso_v4_doi_list_lock);
 
        cipso_v4_cache_invalidate();
        call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
+       ret_val = 0;
+
+doi_remove_return:
+       audit_buf = netlbl_audit_start(AUDIT_MAC_CIPSOV4_DEL, audit_info);
+       if (audit_buf != NULL) {
+               audit_log_format(audit_buf,
+                                " cipso_doi=%u res=%u",
+                                doi, ret_val == 0 ? 1 : 0);
+               audit_log_end(audit_buf);
+       }
 
-       return 0;
+       return ret_val;
 }
 
 /**
@@ -673,7 +738,7 @@ static int cipso_v4_map_lvl_valid(const struct cipso_v4_doi *doi_def, u8 level)
        switch (doi_def->type) {
        case CIPSO_V4_MAP_PASS:
                return 0;
-       case CIPSO_V4_MAP_STD:
+       case CIPSO_V4_MAP_TRANS:
                if (doi_def->map.std->lvl.cipso[level] < CIPSO_V4_INV_LVL)
                        return 0;
                break;
@@ -702,7 +767,7 @@ static int cipso_v4_map_lvl_hton(const struct cipso_v4_doi *doi_def,
        case CIPSO_V4_MAP_PASS:
                *net_lvl = host_lvl;
                return 0;
-       case CIPSO_V4_MAP_STD:
+       case CIPSO_V4_MAP_TRANS:
                if (host_lvl < doi_def->map.std->lvl.local_size &&
                    doi_def->map.std->lvl.local[host_lvl] < CIPSO_V4_INV_LVL) {
                        *net_lvl = doi_def->map.std->lvl.local[host_lvl];
@@ -736,7 +801,7 @@ static int cipso_v4_map_lvl_ntoh(const struct cipso_v4_doi *doi_def,
        case CIPSO_V4_MAP_PASS:
                *host_lvl = net_lvl;
                return 0;
-       case CIPSO_V4_MAP_STD:
+       case CIPSO_V4_MAP_TRANS:
                map_tbl = doi_def->map.std;
                if (net_lvl < map_tbl->lvl.cipso_size &&
                    map_tbl->lvl.cipso[net_lvl] < CIPSO_V4_INV_LVL) {
@@ -773,7 +838,7 @@ static int cipso_v4_map_cat_rbm_valid(const struct cipso_v4_doi *doi_def,
        switch (doi_def->type) {
        case CIPSO_V4_MAP_PASS:
                return 0;
-       case CIPSO_V4_MAP_STD:
+       case CIPSO_V4_MAP_TRANS:
                cipso_cat_size = doi_def->map.std->cat.cipso_size;
                cipso_array = doi_def->map.std->cat.cipso;
                for (;;) {
@@ -821,7 +886,7 @@ static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def,
        u32 host_cat_size = 0;
        u32 *host_cat_array = NULL;
 
-       if (doi_def->type == CIPSO_V4_MAP_STD) {
+       if (doi_def->type == CIPSO_V4_MAP_TRANS) {
                host_cat_size = doi_def->map.std->cat.local_size;
                host_cat_array = doi_def->map.std->cat.local;
        }
@@ -836,7 +901,7 @@ static int cipso_v4_map_cat_rbm_hton(const struct cipso_v4_doi *doi_def,
                case CIPSO_V4_MAP_PASS:
                        net_spot = host_spot;
                        break;
-               case CIPSO_V4_MAP_STD:
+               case CIPSO_V4_MAP_TRANS:
                        if (host_spot >= host_cat_size)
                                return -EPERM;
                        net_spot = host_cat_array[host_spot];
@@ -882,7 +947,7 @@ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
        u32 net_cat_size = 0;
        u32 *net_cat_array = NULL;
 
-       if (doi_def->type == CIPSO_V4_MAP_STD) {
+       if (doi_def->type == CIPSO_V4_MAP_TRANS) {
                net_cat_size = doi_def->map.std->cat.cipso_size;
                net_cat_array = doi_def->map.std->cat.cipso;
        }
@@ -902,7 +967,7 @@ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def,
                case CIPSO_V4_MAP_PASS:
                        host_spot = net_spot;
                        break;
-               case CIPSO_V4_MAP_STD:
+               case CIPSO_V4_MAP_TRANS:
                        if (net_spot >= net_cat_size)
                                return -EPERM;
                        host_spot = net_cat_array[net_spot];
@@ -1238,7 +1303,7 @@ static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def,
        } else
                tag_len = 4;
 
-       buffer[0] = 0x01;
+       buffer[0] = CIPSO_V4_TAG_RBITMAP;
        buffer[1] = tag_len;
        buffer[3] = level;
 
@@ -1334,7 +1399,7 @@ static int cipso_v4_gentag_enum(const struct cipso_v4_doi *doi_def,
        } else
                tag_len = 4;
 
-       buffer[0] = 0x02;
+       buffer[0] = CIPSO_V4_TAG_ENUM;
        buffer[1] = tag_len;
        buffer[3] = level;
 
@@ -1430,7 +1495,7 @@ static int cipso_v4_gentag_rng(const struct cipso_v4_doi *doi_def,
        } else
                tag_len = 4;
 
-       buffer[0] = 0x05;
+       buffer[0] = CIPSO_V4_TAG_RANGE;
        buffer[1] = tag_len;
        buffer[3] = level;
 
@@ -1484,6 +1549,54 @@ static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def,
 }
 
 /**
+ * cipso_v4_gentag_loc - Generate a CIPSO local tag (non-standard)
+ * @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 local tag.  Returns the size of the tag
+ * on success, negative values on failure.
+ *
+ */
+static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def,
+                              const struct netlbl_lsm_secattr *secattr,
+                              unsigned char *buffer,
+                              u32 buffer_len)
+{
+       if (!(secattr->flags & NETLBL_SECATTR_SECID))
+               return -EPERM;
+
+       buffer[0] = CIPSO_V4_TAG_LOCAL;
+       buffer[1] = CIPSO_V4_TAG_LOC_BLEN;
+       *(u32 *)&buffer[2] = secattr->attr.secid;
+
+       return CIPSO_V4_TAG_LOC_BLEN;
+}
+
+/**
+ * cipso_v4_parsetag_loc - Parse a CIPSO local tag
+ * @doi_def: the DOI definition
+ * @tag: the CIPSO tag
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Parse a CIPSO local tag and return the security attributes in @secattr.
+ * Return zero on success, negatives values on failure.
+ *
+ */
+static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def,
+                                const unsigned char *tag,
+                                struct netlbl_lsm_secattr *secattr)
+{
+       secattr->attr.secid = *(u32 *)&tag[2];
+       secattr->flags |= NETLBL_SECATTR_SECID;
+
+       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
  *
@@ -1502,7 +1615,7 @@ static int cipso_v4_parsetag_rng(const struct cipso_v4_doi *doi_def,
  *   that is unrecognized."
  *
  */
-int cipso_v4_validate(unsigned char **option)
+int cipso_v4_validate(const struct sk_buff *skb, unsigned char **option)
 {
        unsigned char *opt = *option;
        unsigned char *tag;
@@ -1527,7 +1640,7 @@ int cipso_v4_validate(unsigned char **option)
                goto validate_return_locked;
        }
 
-       opt_iter = 6;
+       opt_iter = CIPSO_V4_HDR_LEN;
        tag = opt + opt_iter;
        while (opt_iter < opt_len) {
                for (tag_iter = 0; doi_def->tags[tag_iter] != tag[0];)
@@ -1545,7 +1658,7 @@ int cipso_v4_validate(unsigned char **option)
 
                switch (tag[0]) {
                case CIPSO_V4_TAG_RBITMAP:
-                       if (tag_len < 4) {
+                       if (tag_len < CIPSO_V4_TAG_RBM_BLEN) {
                                err_offset = opt_iter + 1;
                                goto validate_return_locked;
                        }
@@ -1563,7 +1676,7 @@ int cipso_v4_validate(unsigned char **option)
                                        err_offset = opt_iter + 3;
                                        goto validate_return_locked;
                                }
-                               if (tag_len > 4 &&
+                               if (tag_len > CIPSO_V4_TAG_RBM_BLEN &&
                                    cipso_v4_map_cat_rbm_valid(doi_def,
                                                            &tag[4],
                                                            tag_len - 4) < 0) {
@@ -1573,7 +1686,7 @@ int cipso_v4_validate(unsigned char **option)
                        }
                        break;
                case CIPSO_V4_TAG_ENUM:
-                       if (tag_len < 4) {
+                       if (tag_len < CIPSO_V4_TAG_ENUM_BLEN) {
                                err_offset = opt_iter + 1;
                                goto validate_return_locked;
                        }
@@ -1583,7 +1696,7 @@ int cipso_v4_validate(unsigned char **option)
                                err_offset = opt_iter + 3;
                                goto validate_return_locked;
                        }
-                       if (tag_len > 4 &&
+                       if (tag_len > CIPSO_V4_TAG_ENUM_BLEN &&
                            cipso_v4_map_cat_enum_valid(doi_def,
                                                        &tag[4],
                                                        tag_len - 4) < 0) {
@@ -1592,7 +1705,7 @@ int cipso_v4_validate(unsigned char **option)
                        }
                        break;
                case CIPSO_V4_TAG_RANGE:
-                       if (tag_len < 4) {
+                       if (tag_len < CIPSO_V4_TAG_RNG_BLEN) {
                                err_offset = opt_iter + 1;
                                goto validate_return_locked;
                        }
@@ -1602,7 +1715,7 @@ int cipso_v4_validate(unsigned char **option)
                                err_offset = opt_iter + 3;
                                goto validate_return_locked;
                        }
-                       if (tag_len > 4 &&
+                       if (tag_len > CIPSO_V4_TAG_RNG_BLEN &&
                            cipso_v4_map_cat_rng_valid(doi_def,
                                                       &tag[4],
                                                       tag_len - 4) < 0) {
@@ -1610,6 +1723,19 @@ int cipso_v4_validate(unsigned char **option)
                                goto validate_return_locked;
                        }
                        break;
+               case CIPSO_V4_TAG_LOCAL:
+                       /* This is a non-standard tag that we only allow for
+                        * local connections, so if the incoming interface is
+                        * not the loopback device drop the packet. */
+                       if (!(skb->dev->flags & IFF_LOOPBACK)) {
+                               err_offset = opt_iter;
+                               goto validate_return_locked;
+                       }
+                       if (tag_len != CIPSO_V4_TAG_LOC_BLEN) {
+                               err_offset = opt_iter + 1;
+                               goto validate_return_locked;
+                       }
+                       break;
                default:
                        err_offset = opt_iter;
                        goto validate_return_locked;
@@ -1712,6 +1838,12 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
                                                   &buf[CIPSO_V4_HDR_LEN],
                                                   buf_len - CIPSO_V4_HDR_LEN);
                        break;
+               case CIPSO_V4_TAG_LOCAL:
+                       ret_val = cipso_v4_gentag_loc(doi_def,
+                                                  secattr,
+                                                  &buf[CIPSO_V4_HDR_LEN],
+                                                  buf_len - CIPSO_V4_HDR_LEN);
+                       break;
                default:
                        return -EPERM;
                }
@@ -1810,6 +1942,80 @@ socket_setattr_failure:
 }
 
 /**
+ * cipso_v4_sock_delattr - Delete the CIPSO option from a socket
+ * @sk: the socket
+ *
+ * Description:
+ * Removes the CIPSO option from a socket, if present.
+ *
+ */
+void cipso_v4_sock_delattr(struct sock *sk)
+{
+       u8 hdr_delta;
+       struct ip_options *opt;
+       struct inet_sock *sk_inet;
+
+       sk_inet = inet_sk(sk);
+       opt = sk_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++;
+               hdr_delta = opt->optlen;
+               opt->optlen = (optlen_new + 3) & ~3;
+               hdr_delta -= opt->optlen;
+       } else {
+               /* only the cipso option was present on the socket so we can
+                * remove the entire option struct */
+               sk_inet->opt = NULL;
+               hdr_delta = opt->optlen;
+               kfree(opt);
+       }
+
+       if (sk_inet->is_icsk && hdr_delta > 0) {
+               struct inet_connection_sock *sk_conn = inet_csk(sk);
+               sk_conn->icsk_ext_hdr_len -= hdr_delta;
+               sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie);
+       }
+}
+
+/**
  * cipso_v4_getattr - Helper function for the cipso_v4_*_getattr functions
  * @cipso: the CIPSO v4 option
  * @secattr: the security attributes
@@ -1847,6 +2053,9 @@ static int cipso_v4_getattr(const unsigned char *cipso,
        case CIPSO_V4_TAG_RANGE:
                ret_val = cipso_v4_parsetag_rng(doi_def, &cipso[6], secattr);
                break;
+       case CIPSO_V4_TAG_LOCAL:
+               ret_val = cipso_v4_parsetag_loc(doi_def, &cipso[6], secattr);
+               break;
        }
        if (ret_val == 0)
                secattr->type = NETLBL_NLTYPE_CIPSOV4;
@@ -1902,9 +2111,10 @@ int cipso_v4_skbuff_setattr(struct sk_buff *skb,
        u32 opt_len;
        int len_delta;
 
-       buf_len = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
-       if (buf_len < 0)
-               return buf_len;
+       ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr);
+       if (ret_val < 0)
+               return ret_val;
+       buf_len = ret_val;
        opt_len = (buf_len + 3) & ~3;
 
        /* we overwrite any existing options to ensure that we have enough