diff options
| -rw-r--r-- | net/ipv4/cipso_ipv4.c | 113 |
1 files changed, 53 insertions, 60 deletions
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index 23a968f754b..a056278ad62 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -958,35 +958,28 @@ static int cipso_v4_map_cat_rbm_ntoh(const struct cipso_v4_doi *doi_def, * Protocol Handling Functions */ +#define CIPSO_V4_OPT_LEN_MAX 40 #define CIPSO_V4_HDR_LEN 6 /** * cipso_v4_gentag_hdr - Generate a CIPSO option header * @doi_def: the DOI definition - * @len: the total tag length in bytes + * @len: the total tag length in bytes, not including this header * @buf: the CIPSO option buffer * * Description: - * Write a CIPSO header into the beginning of @buffer. Return zero on success, - * negative values on failure. + * Write a CIPSO header into the beginning of @buffer. * */ -static int cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, - u32 len, - unsigned char *buf) +static void cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, + unsigned char *buf, + u32 len) { - if (CIPSO_V4_HDR_LEN + len > 40) - return -ENOSPC; - buf[0] = IPOPT_CIPSO; buf[1] = CIPSO_V4_HDR_LEN + len; *(__be32 *)&buf[2] = htonl(doi_def->doi); - - return 0; } -#define CIPSO_V4_TAG1_CAT_LEN 30 - /** * cipso_v4_gentag_rbm - Generate a CIPSO restricted bitmap tag (type #1) * @doi_def: the DOI definition @@ -997,71 +990,50 @@ static int cipso_v4_gentag_hdr(const struct cipso_v4_doi *doi_def, * Description: * Generate a CIPSO option using the restricted bitmap tag, tag type #1. The * actual buffer length may be larger than the indicated size due to - * translation between host and network category bitmaps. Returns zero on - * success, negative values on failure. + * translation between host and network category bitmaps. Returns the size of + * the tag on success, negative values on failure. * */ static int cipso_v4_gentag_rbm(const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr, - unsigned char **buffer, - u32 *buffer_len) + unsigned char *buffer, + u32 buffer_len) { int ret_val; - unsigned char *buf = NULL; - u32 buf_len; + u32 tag_len; u32 level; if ((secattr->flags & NETLBL_SECATTR_MLS_LVL) == 0) return -EPERM; - if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { - buf = kzalloc(CIPSO_V4_HDR_LEN + 4 + CIPSO_V4_TAG1_CAT_LEN, - GFP_ATOMIC); - if (buf == NULL) - return -ENOMEM; + 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_rbm_hton(doi_def, secattr->mls_cat, secattr->mls_cat_len, - &buf[CIPSO_V4_HDR_LEN + 4], - CIPSO_V4_TAG1_CAT_LEN); + &buffer[4], + buffer_len - 4); if (ret_val < 0) - goto gentag_failure; + return ret_val; /* This will send packets using the "optimized" format when * possibile as specified in section 3.4.2.6 of the * CIPSO draft. */ if (cipso_v4_rbm_optfmt && ret_val > 0 && ret_val <= 10) - buf_len = 14; + tag_len = 14; else - buf_len = 4 + ret_val; - } else { - buf = kzalloc(CIPSO_V4_HDR_LEN + 4, GFP_ATOMIC); - if (buf == NULL) - return -ENOMEM; - buf_len = 4; - } - - ret_val = cipso_v4_map_lvl_hton(doi_def, secattr->mls_lvl, &level); - if (ret_val != 0) - goto gentag_failure; - - ret_val = cipso_v4_gentag_hdr(doi_def, buf_len, buf); - if (ret_val != 0) - goto gentag_failure; - - buf[CIPSO_V4_HDR_LEN] = 0x01; - buf[CIPSO_V4_HDR_LEN + 1] = buf_len; - buf[CIPSO_V4_HDR_LEN + 3] = level; + tag_len = 4 + ret_val; + } else + tag_len = 4; - *buffer = buf; - *buffer_len = CIPSO_V4_HDR_LEN + buf_len; + buffer[0] = 0x01; + buffer[1] = tag_len; + buffer[3] = level; - return 0; - -gentag_failure: - kfree(buf); - return ret_val; + return tag_len; } /** @@ -1284,7 +1256,7 @@ int cipso_v4_socket_setattr(const struct socket *sock, { int ret_val = -EPERM; u32 iter; - unsigned char *buf = NULL; + unsigned char *buf; u32 buf_len = 0; u32 opt_len; struct ip_options *opt = NULL; @@ -1300,17 +1272,28 @@ int cipso_v4_socket_setattr(const struct socket *sock, if (sk == NULL) return 0; + /* 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 socket_setattr_failure; + } + /* XXX - This code assumes only one tag per CIPSO option which isn't * really a good assumption to make but since we only support the MAC * tags right now it is a safe assumption. */ iter = 0; do { + memset(buf, 0, buf_len); switch (doi_def->tags[iter]) { case CIPSO_V4_TAG_RBITMAP: ret_val = cipso_v4_gentag_rbm(doi_def, - secattr, - &buf, - &buf_len); + secattr, + &buf[CIPSO_V4_HDR_LEN], + buf_len - CIPSO_V4_HDR_LEN); break; default: ret_val = -EPERM; @@ -1318,11 +1301,13 @@ int cipso_v4_socket_setattr(const struct socket *sock, } iter++; - } while (ret_val != 0 && + } while (ret_val < 0 && iter < CIPSO_V4_TAG_MAXCNT && doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); - if (ret_val != 0) + if (ret_val < 0) goto socket_setattr_failure; + cipso_v4_gentag_hdr(doi_def, buf, ret_val); + buf_len = CIPSO_V4_HDR_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 @@ -1396,6 +1381,10 @@ int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) rcu_read_unlock(); return -ENOMSG; } + + /* XXX - This code assumes only one tag per CIPSO option which isn't + * really a good assumption to make but since we only support the MAC + * tags right now it is a safe assumption. */ switch (cipso_ptr[6]) { case CIPSO_V4_TAG_RBITMAP: ret_val = cipso_v4_parsetag_rbm(doi_def, @@ -1458,6 +1447,10 @@ int cipso_v4_skbuff_getattr(const struct sk_buff *skb, doi_def = cipso_v4_doi_getdef(doi); if (doi_def == NULL) goto skbuff_getattr_return; + + /* XXX - This code assumes only one tag per CIPSO option which isn't + * really a good assumption to make but since we only support the MAC + * tags right now it is a safe assumption. */ switch (cipso_ptr[6]) { case CIPSO_V4_TAG_RBITMAP: ret_val = cipso_v4_parsetag_rbm(doi_def, |