diff options
| -rw-r--r-- | include/net/cipso_ipv4.h | 16 | ||||
| -rw-r--r-- | include/net/netlabel.h | 9 | ||||
| -rw-r--r-- | net/ipv4/cipso_ipv4.c | 222 | ||||
| -rw-r--r-- | net/netlabel/netlabel_kapi.c | 60 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 50 | ||||
| -rw-r--r-- | security/selinux/include/netlabel.h | 9 | ||||
| -rw-r--r-- | security/selinux/include/objsec.h | 1 | ||||
| -rw-r--r-- | security/selinux/netlabel.c | 68 |
8 files changed, 393 insertions, 42 deletions
diff --git a/include/net/cipso_ipv4.h b/include/net/cipso_ipv4.h index 5fe6556..2ce093b 100644 --- a/include/net/cipso_ipv4.h +++ b/include/net/cipso_ipv4.h @@ -208,6 +208,10 @@ int cipso_v4_sock_setattr(struct sock *sk, const struct cipso_v4_doi *doi_def, const struct netlbl_lsm_secattr *secattr); int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr); +int cipso_v4_skbuff_setattr(struct sk_buff *skb, + const struct cipso_v4_doi *doi_def, + const struct netlbl_lsm_secattr *secattr); +int cipso_v4_skbuff_delattr(struct sk_buff *skb); int cipso_v4_skbuff_getattr(const struct sk_buff *skb, struct netlbl_lsm_secattr *secattr); int cipso_v4_validate(unsigned char **option); @@ -232,6 +236,18 @@ static inline int cipso_v4_sock_getattr(struct sock *sk, return -ENOSYS; } +static inline int cipso_v4_skbuff_setattr(struct sk_buff *skb, + const struct cipso_v4_doi *doi_def, + const struct netlbl_lsm_secattr *secattr) +{ + return -ENOSYS; +} + +static inline int cipso_v4_skbuff_delattr(struct sk_buff *skb) +{ + return -ENOSYS; +} + static inline int cipso_v4_skbuff_getattr(const struct sk_buff *skb, struct netlbl_lsm_secattr *secattr) { diff --git a/include/net/netlabel.h b/include/net/netlabel.h index 0729f8c..3f67e6d 100644 --- a/include/net/netlabel.h +++ b/include/net/netlabel.h @@ -382,6 +382,9 @@ int netlbl_sock_setattr(struct sock *sk, const struct netlbl_lsm_secattr *secattr); int netlbl_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr); +int netlbl_skbuff_setattr(struct sk_buff *skb, + u16 family, + const struct netlbl_lsm_secattr *secattr); int netlbl_skbuff_getattr(const struct sk_buff *skb, u16 family, struct netlbl_lsm_secattr *secattr); @@ -451,6 +454,12 @@ static inline int netlbl_sock_getattr(struct sock *sk, { return -ENOSYS; } +static inline int netlbl_skbuff_setattr(struct sk_buff *skb, + u16 family, + const struct netlbl_lsm_secattr *secattr) +{ + return -ENOSYS; +} static inline int netlbl_skbuff_getattr(const struct sk_buff *skb, u16 family, struct netlbl_lsm_secattr *secattr) diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c index bf87edd..e13d6db 100644 --- a/net/ipv4/cipso_ipv4.c +++ b/net/ipv4/cipso_ipv4.c @@ -13,7 +13,7 @@ */ /* - * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 + * (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -1665,48 +1665,27 @@ void cipso_v4_error(struct sk_buff *skb, int error, u32 gateway) } /** - * cipso_v4_sock_setattr - Add a CIPSO option to a socket - * @sk: the socket + * cipso_v4_genopt - Generate a CIPSO option + * @buf: the option buffer + * @buf_len: the size of opt_buf * @doi_def: the CIPSO DOI to use - * @secattr: the specific security attributes of the socket + * @secattr: the security attributes * * Description: - * Set the CIPSO option on the given socket using the DOI definition and - * security attributes passed to the function. This function requires - * exclusive access to @sk, which means it either needs to be in the - * process of being created or locked. Returns zero on success and negative - * values on failure. + * Generate a CIPSO option using the DOI definition and security attributes + * passed to the function. Returns the length of the option on success and + * negative values on failure. * */ -int cipso_v4_sock_setattr(struct sock *sk, - const struct cipso_v4_doi *doi_def, - const struct netlbl_lsm_secattr *secattr) +static int cipso_v4_genopt(unsigned char *buf, u32 buf_len, + const struct cipso_v4_doi *doi_def, + const struct netlbl_lsm_secattr *secattr) { - int ret_val = -EPERM; + int ret_val; u32 iter; - unsigned char *buf; - u32 buf_len = 0; - u32 opt_len; - struct ip_options *opt = NULL; - struct inet_sock *sk_inet; - struct inet_connection_sock *sk_conn; - - /* In the case of sock_create_lite(), the sock->sk field is not - * defined yet but it is not a problem as the only users of these - * "lite" PF_INET sockets are functions which do an accept() call - * afterwards so we will label the socket as part of the accept(). */ - 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; - } + if (buf_len <= CIPSO_V4_HDR_LEN) + return -ENOSPC; /* 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 @@ -1734,8 +1713,7 @@ int cipso_v4_sock_setattr(struct sock *sk, buf_len - CIPSO_V4_HDR_LEN); break; default: - ret_val = -EPERM; - goto socket_setattr_failure; + return -EPERM; } iter++; @@ -1743,9 +1721,58 @@ int cipso_v4_sock_setattr(struct sock *sk, iter < CIPSO_V4_TAG_MAXCNT && doi_def->tags[iter] != CIPSO_V4_TAG_INVALID); if (ret_val < 0) - goto socket_setattr_failure; + return ret_val; cipso_v4_gentag_hdr(doi_def, buf, ret_val); - buf_len = CIPSO_V4_HDR_LEN + ret_val; + return CIPSO_V4_HDR_LEN + ret_val; +} + +/** + * cipso_v4_sock_setattr - Add a CIPSO option to a socket + * @sk: the 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. This function requires + * exclusive access to @sk, which means it either needs to be in the + * process of being created or locked. Returns zero on success and negative + * values on failure. + * + */ +int cipso_v4_sock_setattr(struct sock *sk, + 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_sock *sk_inet; + struct inet_connection_sock *sk_conn; + + /* In the case of sock_create_lite(), the sock->sk field is not + * defined yet but it is not a problem as the only users of these + * "lite" PF_INET sockets are functions which do an accept() call + * afterwards so we will label the socket as part of the accept(). */ + 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; + } + + ret_val = cipso_v4_genopt(buf, buf_len, doi_def, secattr); + if (ret_val < 0) + goto socket_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 @@ -1854,6 +1881,123 @@ int cipso_v4_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) } /** + * cipso_v4_skbuff_setattr - Set the CIPSO option on a packet + * @skb: the packet + * @secattr: the security attributes + * + * Description: + * Set the CIPSO option on the given packet based on the security attributes. + * Returns a pointer to the IP header on success and NULL on failure. + * + */ +int cipso_v4_skbuff_setattr(struct sk_buff *skb, + const struct cipso_v4_doi *doi_def, + const struct netlbl_lsm_secattr *secattr) +{ + int ret_val; + struct iphdr *iph; + struct ip_options *opt = &IPCB(skb)->opt; + unsigned char buf[CIPSO_V4_OPT_LEN_MAX]; + u32 buf_len = CIPSO_V4_OPT_LEN_MAX; + u32 opt_len; + int len_delta; + + buf_len = cipso_v4_genopt(buf, buf_len, doi_def, secattr); + if (buf_len < 0) + return buf_len; + opt_len = (buf_len + 3) & ~3; + + /* we overwrite any existing options to ensure that we have enough + * room for the CIPSO option, the reason is that we _need_ to guarantee + * that the security label is applied to the packet - we do the same + * thing when using the socket options and it hasn't caused a problem, + * if we need to we can always revisit this choice later */ + + len_delta = opt_len - opt->optlen; + /* if we don't ensure enough headroom we could panic on the skb_push() + * call below so make sure we have enough, we are also "mangling" the + * packet so we should probably do a copy-on-write call anyway */ + ret_val = skb_cow(skb, skb_headroom(skb) + len_delta); + if (ret_val < 0) + return ret_val; + + if (len_delta > 0) { + /* we assume that the header + opt->optlen have already been + * "pushed" in ip_options_build() or similar */ + iph = ip_hdr(skb); + skb_push(skb, len_delta); + memmove((char *)iph - len_delta, iph, iph->ihl << 2); + skb_reset_network_header(skb); + iph = ip_hdr(skb); + } else if (len_delta < 0) { + iph = ip_hdr(skb); + memset(iph + 1, IPOPT_NOP, opt->optlen); + } else + iph = ip_hdr(skb); + + if (opt->optlen > 0) + memset(opt, 0, sizeof(*opt)); + opt->optlen = opt_len; + opt->cipso = sizeof(struct iphdr); + opt->is_changed = 1; + + /* we have to do the following because we are being called from a + * netfilter hook which means the packet already has had the header + * fields populated and the checksum calculated - yes this means we + * are doing more work than needed but we do it to keep the core + * stack clean and tidy */ + memcpy(iph + 1, buf, buf_len); + if (opt_len > buf_len) + memset((char *)(iph + 1) + buf_len, 0, opt_len - buf_len); + if (len_delta != 0) { + iph->ihl = 5 + (opt_len >> 2); + iph->tot_len = htons(skb->len); + } + ip_send_check(iph); + + return 0; +} + +/** + * cipso_v4_skbuff_delattr - Delete any CIPSO options from a packet + * @skb: the packet + * + * Description: + * Removes any and all CIPSO options from the given packet. Returns zero on + * success, negative values on failure. + * + */ +int cipso_v4_skbuff_delattr(struct sk_buff *skb) +{ + int ret_val; + struct iphdr *iph; + struct ip_options *opt = &IPCB(skb)->opt; + unsigned char *cipso_ptr; + + if (opt->cipso == 0) + return 0; + + /* since we are changing the packet we should make a copy */ + ret_val = skb_cow(skb, skb_headroom(skb)); + if (ret_val < 0) + return ret_val; + + /* the easiest thing to do is just replace the cipso option with noop + * options since we don't change the size of the packet, although we + * still need to recalculate the checksum */ + + iph = ip_hdr(skb); + cipso_ptr = (unsigned char *)iph + opt->cipso; + memset(cipso_ptr, IPOPT_NOOP, cipso_ptr[1]); + opt->cipso = 0; + opt->is_changed = 1; + + ip_send_check(iph); + + return 0; +} + +/** * cipso_v4_skbuff_getattr - Get the security attributes from the CIPSO option * @skb: the packet * @secattr: the security attributes diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c index 8b820dc..cc8047d 100644 --- a/net/netlabel/netlabel_kapi.c +++ b/net/netlabel/netlabel_kapi.c @@ -473,6 +473,66 @@ int netlbl_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr) } /** + * netlbl_skbuff_setattr - Label a packet using the correct protocol + * @skb: the packet + * @family: protocol family + * @secattr: the security attributes + * + * Description: + * Attach the correct label to the given packet using the security attributes + * specified in @secattr. Returns zero on success, negative values on failure. + * + */ +int netlbl_skbuff_setattr(struct sk_buff *skb, + u16 family, + const struct netlbl_lsm_secattr *secattr) +{ + int ret_val; + struct iphdr *hdr4; + struct netlbl_domaddr4_map *af4_entry; + + rcu_read_lock(); + switch (family) { + case AF_INET: + hdr4 = ip_hdr(skb); + af4_entry = netlbl_domhsh_getentry_af4(secattr->domain, + hdr4->daddr); + if (af4_entry == NULL) { + ret_val = -ENOENT; + goto skbuff_setattr_return; + } + switch (af4_entry->type) { + case NETLBL_NLTYPE_CIPSOV4: + ret_val = cipso_v4_skbuff_setattr(skb, + af4_entry->type_def.cipsov4, + secattr); + break; + case NETLBL_NLTYPE_UNLABELED: + /* just delete the protocols we support for right now + * but we could remove other protocols if needed */ + ret_val = cipso_v4_skbuff_delattr(skb); + break; + default: + ret_val = -ENOENT; + } + break; +#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) + case AF_INET6: + /* since we don't support any IPv6 labeling protocols right + * now we can optimize everything away until we do */ + ret_val = 0; + break; +#endif /* IPv6 */ + default: + ret_val = 0; + } + +skbuff_setattr_return: + rcu_read_unlock(); + return ret_val; +} + +/** * netlbl_skbuff_getattr - Determine the security attributes of a packet * @skb: the packet * @family: protocol family diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index a91146a..7432bdd 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4407,13 +4407,15 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, u32 peer_sid; struct avc_audit_data ad; u8 secmark_active; + u8 netlbl_active; u8 peerlbl_active; if (!selinux_policycap_netpeer) return NF_ACCEPT; secmark_active = selinux_secmark_enabled(); - peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled(); + netlbl_active = netlbl_enabled(); + peerlbl_active = netlbl_active || selinux_xfrm_enabled(); if (!secmark_active && !peerlbl_active) return NF_ACCEPT; @@ -4440,6 +4442,14 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex, SECCLASS_PACKET, PACKET__FORWARD_IN, &ad)) return NF_DROP; + if (netlbl_active) + /* we do this in the FORWARD path and not the POST_ROUTING + * path because we want to make sure we apply the necessary + * labeling before IPsec is applied so we can leverage AH + * protection */ + if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0) + return NF_DROP; + return NF_ACCEPT; } @@ -4463,6 +4473,37 @@ static unsigned int selinux_ipv6_forward(unsigned int hooknum, } #endif /* IPV6 */ +static unsigned int selinux_ip_output(struct sk_buff *skb, + u16 family) +{ + u32 sid; + + if (!netlbl_enabled()) + return NF_ACCEPT; + + /* we do this in the LOCAL_OUT path and not the POST_ROUTING path + * because we want to make sure we apply the necessary labeling + * before IPsec is applied so we can leverage AH protection */ + if (skb->sk) { + struct sk_security_struct *sksec = skb->sk->sk_security; + sid = sksec->sid; + } else + sid = SECINITSID_KERNEL; + if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0) + return NF_DROP; + + return NF_ACCEPT; +} + +static unsigned int selinux_ipv4_output(unsigned int hooknum, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *)) +{ + return selinux_ip_output(skb, PF_INET); +} + static int selinux_ip_postroute_iptables_compat(struct sock *sk, int ifindex, struct avc_audit_data *ad, @@ -5700,6 +5741,13 @@ static struct nf_hook_ops selinux_ipv4_ops[] = { .pf = PF_INET, .hooknum = NF_INET_FORWARD, .priority = NF_IP_PRI_SELINUX_FIRST, + }, + { + .hook = selinux_ipv4_output, + .owner = THIS_MODULE, + .pf = PF_INET, + .hooknum = NF_INET_LOCAL_OUT, + .priority = NF_IP_PRI_SELINUX_FIRST, } }; diff --git a/security/selinux/include/netlabel.h b/security/selinux/include/netlabel.h index d4e3ac8..b3e6ae0 100644 --- a/security/selinux/include/netlabel.h +++ b/security/selinux/include/netlabel.h @@ -48,6 +48,9 @@ int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, u16 family, u32 *type, u32 *sid); +int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, + u16 family, + u32 sid); void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock); int selinux_netlbl_socket_post_create(struct socket *sock); @@ -88,6 +91,12 @@ static inline int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, *sid = SECSID_NULL; return 0; } +static inline int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, + u16 family, + u32 sid) +{ + return 0; +} static inline void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock) diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h index 91070ab..f46dd1c 100644 --- a/security/selinux/include/objsec.h +++ b/security/selinux/include/objsec.h @@ -117,6 +117,7 @@ struct sk_security_struct { NLBL_UNSET = 0, NLBL_REQUIRE, NLBL_LABELED, + NLBL_REQSKB, } nlbl_state; #endif }; diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c index 4053f7f..090404d 100644 --- a/security/selinux/netlabel.c +++ b/security/selinux/netlabel.c @@ -9,7 +9,7 @@ */ /* - * (c) Copyright Hewlett-Packard Development Company, L.P., 2007 + * (c) Copyright Hewlett-Packard Development Company, L.P., 2007, 2008 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -31,6 +31,8 @@ #include <linux/rcupdate.h> #include <net/sock.h> #include <net/netlabel.h> +#include <net/inet_sock.h> +#include <net/inet_connection_sock.h> #include "objsec.h" #include "security.h" @@ -77,6 +79,8 @@ static int selinux_netlbl_sock_setsid(struct sock *sk) int rc; struct sk_security_struct *sksec = sk->sk_security; struct netlbl_lsm_secattr secattr; + struct inet_sock *sk_inet; + struct inet_connection_sock *sk_conn; if (sksec->nlbl_state != NLBL_REQUIRE) return 0; @@ -87,8 +91,29 @@ static int selinux_netlbl_sock_setsid(struct sock *sk) if (rc != 0) goto sock_setsid_return; rc = netlbl_sock_setattr(sk, &secattr); - if (rc == 0) + switch (rc) { + case 0: sksec->nlbl_state = NLBL_LABELED; + break; + case -EDESTADDRREQ: + /* we are going to possibly end up labeling the individual + * packets later which is problematic for stream sockets + * because of the additional IP header size, our solution is to + * allow for the maximum IP header length (40 bytes for IPv4, + * we don't have to worry about IPv6 yet) just in case */ + sk_inet = inet_sk(sk); + if (sk_inet->is_icsk) { + sk_conn = inet_csk(sk); + if (sk_inet->opt) + sk_conn->icsk_ext_hdr_len -= + sk_inet->opt->optlen; + sk_conn->icsk_ext_hdr_len += 40; + sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); + } + sksec->nlbl_state = NLBL_REQSKB; + rc = 0; + break; + } sock_setsid_return: netlbl_secattr_destroy(&secattr); @@ -183,6 +208,45 @@ int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, } /** + * selinux_netlbl_skbuff_setsid - Set the NetLabel on a packet given a sid + * @skb: the packet + * @family: protocol family + * @sid: the SID + * + * Description + * Call the NetLabel mechanism to set the label of a packet using @sid. + * Returns zero on auccess, negative values on failure. + * + */ +int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, + u16 family, + u32 sid) +{ + int rc; + struct netlbl_lsm_secattr secattr; + struct sock *sk; + + /* if this is a locally generated packet check to see if it is already + * being labeled by it's parent socket, if it is just exit */ + sk = skb->sk; + if (sk != NULL) { + struct sk_security_struct *sksec = sk->sk_security; + if (sksec->nlbl_state != NLBL_REQSKB) + return 0; + } + + netlbl_secattr_init(&secattr); + rc = security_netlbl_sid_to_secattr(sid, &secattr); + if (rc != 0) + goto skbuff_setsid_return; + rc = netlbl_skbuff_setattr(skb, family, &secattr); + +skbuff_setsid_return: + netlbl_secattr_destroy(&secattr); + return rc; +} + +/** * selinux_netlbl_sock_graft - Netlabel the new socket * @sk: the new connection * @sock: the new socket |