From 7198e2eeb44b3fe7cc97f997824002da47a9c644 Mon Sep 17 00:00:00 2001 From: Etienne Basset Date: Tue, 24 Mar 2009 20:53:24 +0100 Subject: smack: convert smack to standard linux lists the following patch (on top of 2.6.29) converts Smack lists to standard linux lists Please review and consider for inclusion in 2.6.30-rc regards, Etienne Signed-off-by: Etienne Basset Acked-by: Casey Schaufler --- security/smack/smack.h | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) (limited to 'security/smack/smack.h') diff --git a/security/smack/smack.h b/security/smack/smack.h index b79582e4fbfd..64164f8fde70 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -18,6 +18,8 @@ #include #include #include +#include +#include /* * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is @@ -59,17 +61,10 @@ struct inode_smack { * A label access rule. */ struct smack_rule { - char *smk_subject; - char *smk_object; - int smk_access; -}; - -/* - * An entry in the table of permitted label accesses. - */ -struct smk_list_entry { - struct smk_list_entry *smk_next; - struct smack_rule smk_rule; + struct list_head list; + char *smk_subject; + char *smk_object; + int smk_access; }; /* @@ -85,7 +80,7 @@ struct smack_cipso { * An entry in the table identifying hosts. */ struct smk_netlbladdr { - struct smk_netlbladdr *smk_next; + struct list_head list; struct sockaddr_in smk_host; /* network address */ struct in_addr smk_mask; /* network mask */ char *smk_label; /* label */ @@ -113,7 +108,7 @@ struct smk_netlbladdr { * the cipso direct mapping in used internally. */ struct smack_known { - struct smack_known *smk_next; + struct list_head list; char smk_known[SMK_LABELLEN]; u32 smk_secid; struct smack_cipso *smk_cipso; @@ -206,7 +201,6 @@ extern int smack_cipso_direct; extern char *smack_net_ambient; extern char *smack_onlycap; -extern struct smack_known *smack_known; extern struct smack_known smack_known_floor; extern struct smack_known smack_known_hat; extern struct smack_known smack_known_huh; @@ -214,8 +208,10 @@ extern struct smack_known smack_known_invalid; extern struct smack_known smack_known_star; extern struct smack_known smack_known_web; -extern struct smk_list_entry *smack_list; -extern struct smk_netlbladdr *smack_netlbladdrs; +extern struct list_head smack_known_list; +extern struct list_head smack_rule_list; +extern struct list_head smk_netlbladdr_list; + extern struct security_operations smack_ops; /* -- cgit v1.2.3 From 07feee8f812f7327a46186f7604df312c8c81962 Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Fri, 27 Mar 2009 17:10:54 -0400 Subject: netlabel: Cleanup the Smack/NetLabel code to fix incoming TCP connections This patch cleans up a lot of the Smack network access control code. The largest changes are to fix the labeling of incoming TCP connections in a manner similar to the recent SELinux changes which use the security_inet_conn_request() hook to label the request_sock and let the label move to the child socket via the normal network stack mechanisms. In addition to the incoming TCP connection fixes this patch also removes the smk_labled field from the socket_smack struct as the minor optimization advantage was outweighed by the difficulty in maintaining it's proper state. Signed-off-by: Paul Moore Acked-by: Casey Schaufler Signed-off-by: James Morris --- include/net/netlabel.h | 5 + net/netlabel/netlabel_kapi.c | 13 +++ security/smack/smack.h | 1 - security/smack/smack_lsm.c | 260 ++++++++++++++++++++++++------------------- 4 files changed, 161 insertions(+), 118 deletions(-) (limited to 'security/smack/smack.h') diff --git a/include/net/netlabel.h b/include/net/netlabel.h index bdb10e5183d5..60ebbc1fef46 100644 --- a/include/net/netlabel.h +++ b/include/net/netlabel.h @@ -417,6 +417,7 @@ int netlbl_conn_setattr(struct sock *sk, const struct netlbl_lsm_secattr *secattr); int netlbl_req_setattr(struct request_sock *req, const struct netlbl_lsm_secattr *secattr); +void netlbl_req_delattr(struct request_sock *req); int netlbl_skbuff_setattr(struct sk_buff *skb, u16 family, const struct netlbl_lsm_secattr *secattr); @@ -547,6 +548,10 @@ static inline int netlbl_req_setattr(struct request_sock *req, { return -ENOSYS; } +static inline void netlbl_req_delattr(struct request_sock *req) +{ + return; +} static inline int netlbl_skbuff_setattr(struct sk_buff *skb, u16 family, const struct netlbl_lsm_secattr *secattr) diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c index cae2f5f4cac0..b0e582f2d37a 100644 --- a/net/netlabel/netlabel_kapi.c +++ b/net/netlabel/netlabel_kapi.c @@ -860,6 +860,19 @@ req_setattr_return: return ret_val; } +/** +* netlbl_req_delattr - Delete all the NetLabel labels on a socket +* @req: the socket +* +* Description: +* Remove all the NetLabel labeling from @req. +* +*/ +void netlbl_req_delattr(struct request_sock *req) +{ + cipso_v4_req_delattr(req); +} + /** * netlbl_skbuff_setattr - Label a packet using the correct protocol * @skb: the packet diff --git a/security/smack/smack.h b/security/smack/smack.h index 64164f8fde70..5e5a3bcb599a 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -42,7 +42,6 @@ struct superblock_smack { struct socket_smack { char *smk_out; /* outbound label */ char *smk_in; /* inbound label */ - int smk_labeled; /* label scheme */ char smk_packet[SMK_LABELLEN]; /* TCP peer label */ }; diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 23ad420a49aa..8ed502c2ad45 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -7,6 +7,8 @@ * Casey Schaufler * * Copyright (C) 2007 Casey Schaufler + * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. + * Paul Moore * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2, @@ -20,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -1275,7 +1278,6 @@ static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags) ssp->smk_in = csp; ssp->smk_out = csp; - ssp->smk_labeled = SMACK_CIPSO_SOCKET; ssp->smk_packet[0] = '\0'; sk->sk_security = ssp; @@ -1294,6 +1296,39 @@ static void smack_sk_free_security(struct sock *sk) kfree(sk->sk_security); } +/** +* smack_host_label - check host based restrictions +* @sip: the object end +* +* looks for host based access restrictions +* +* This version will only be appropriate for really small sets of single label +* hosts. The caller is responsible for ensuring that the RCU read lock is +* taken before calling this function. +* +* Returns the label of the far end or NULL if it's not special. +*/ +static char *smack_host_label(struct sockaddr_in *sip) +{ + struct smk_netlbladdr *snp; + struct in_addr *siap = &sip->sin_addr; + + if (siap->s_addr == 0) + return NULL; + + list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) + /* + * we break after finding the first match because + * the list is sorted from longest to shortest mask + * so we have found the most specific match + */ + if ((&snp->smk_host.sin_addr)->s_addr == + (siap->s_addr & (&snp->smk_mask)->s_addr)) + return snp->smk_label; + + return NULL; +} + /** * smack_set_catset - convert a capset to netlabel mls categories * @catset: the Smack categories @@ -1365,11 +1400,10 @@ static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) */ static int smack_netlabel(struct sock *sk, int labeled) { - struct socket_smack *ssp; + struct socket_smack *ssp = sk->sk_security; struct netlbl_lsm_secattr secattr; int rc = 0; - ssp = sk->sk_security; /* * Usually the netlabel code will handle changing the * packet labeling based on the label. @@ -1393,20 +1427,44 @@ static int smack_netlabel(struct sock *sk, int labeled) bh_unlock_sock(sk); local_bh_enable(); - /* - * Remember the label scheme used so that it is not - * necessary to do the netlabel setting if it has not - * changed the next time through. - * - * The -EDESTADDRREQ case is an indication that there's - * a single level host involved. - */ - if (rc == 0) - ssp->smk_labeled = labeled; return rc; } +/** + * smack_netlbel_send - Set the secattr on a socket and perform access checks + * @sk: the socket + * @sap: the destination address + * + * Set the correct secattr for the given socket based on the destination + * address and perform any outbound access checks needed. + * + * Returns 0 on success or an error code. + * + */ +static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap) +{ + int rc; + int sk_lbl; + char *hostsp; + struct socket_smack *ssp = sk->sk_security; + + rcu_read_lock(); + hostsp = smack_host_label(sap); + if (hostsp != NULL) { + sk_lbl = SMACK_UNLABELED_SOCKET; + rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); + } else { + sk_lbl = SMACK_CIPSO_SOCKET; + rc = 0; + } + rcu_read_unlock(); + if (rc != 0) + return rc; + + return smack_netlabel(sk, sk_lbl); +} + /** * smack_inode_setsecurity - set smack xattrs * @inode: the object @@ -1488,43 +1546,6 @@ static int smack_socket_post_create(struct socket *sock, int family, return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); } - -/** - * smack_host_label - check host based restrictions - * @sip: the object end - * - * looks for host based access restrictions - * - * This version will only be appropriate for really small - * sets of single label hosts. - * - * Returns the label of the far end or NULL if it's not special. - */ -static char *smack_host_label(struct sockaddr_in *sip) -{ - struct smk_netlbladdr *snp; - struct in_addr *siap = &sip->sin_addr; - - if (siap->s_addr == 0) - return NULL; - - rcu_read_lock(); - list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) { - /* - * we break after finding the first match because - * the list is sorted from longest to shortest mask - * so we have found the most specific match - */ - if ((&snp->smk_host.sin_addr)->s_addr == - (siap->s_addr & (&snp->smk_mask)->s_addr)) { - rcu_read_unlock(); - return snp->smk_label; - } - } - rcu_read_unlock(); - return NULL; -} - /** * smack_socket_connect - connect access check * @sock: the socket @@ -1538,30 +1559,12 @@ static char *smack_host_label(struct sockaddr_in *sip) static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, int addrlen) { - struct socket_smack *ssp = sock->sk->sk_security; - char *hostsp; - int rc; - if (sock->sk == NULL || sock->sk->sk_family != PF_INET) return 0; - if (addrlen < sizeof(struct sockaddr_in)) return -EINVAL; - hostsp = smack_host_label((struct sockaddr_in *)sap); - if (hostsp == NULL) { - if (ssp->smk_labeled != SMACK_CIPSO_SOCKET) - return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); - return 0; - } - - rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); - if (rc != 0) - return rc; - - if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET) - return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET); - return 0; + return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap); } /** @@ -2262,9 +2265,6 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, int size) { struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; - struct socket_smack *ssp = sock->sk->sk_security; - char *hostsp; - int rc; /* * Perfectly reasonable for this to be NULL @@ -2272,22 +2272,7 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, if (sip == NULL || sip->sin_family != PF_INET) return 0; - hostsp = smack_host_label(sip); - if (hostsp == NULL) { - if (ssp->smk_labeled != SMACK_CIPSO_SOCKET) - return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); - return 0; - } - - rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE); - if (rc != 0) - return rc; - - if (ssp->smk_labeled != SMACK_UNLABELED_SOCKET) - return smack_netlabel(sock->sk, SMACK_UNLABELED_SOCKET); - - return 0; - + return smack_netlabel_send(sock->sk, sip); } @@ -2492,31 +2477,24 @@ static int smack_socket_getpeersec_dgram(struct socket *sock, } /** - * smack_sock_graft - graft access state between two sockets - * @sk: fresh sock - * @parent: donor socket + * smack_sock_graft - Initialize a newly created socket with an existing sock + * @sk: child sock + * @parent: parent socket * - * Sets the netlabel socket state on sk from parent + * Set the smk_{in,out} state of an existing sock based on the process that + * is creating the new socket. */ static void smack_sock_graft(struct sock *sk, struct socket *parent) { struct socket_smack *ssp; - int rc; - - if (sk == NULL) - return; - if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) + if (sk == NULL || + (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)) return; ssp = sk->sk_security; ssp->smk_in = ssp->smk_out = current_security(); - ssp->smk_packet[0] = '\0'; - - rc = smack_netlabel(sk, SMACK_CIPSO_SOCKET); - if (rc != 0) - printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", - __func__, -rc); + /* cssp->smk_packet is already set in smack_inet_csk_clone() */ } /** @@ -2531,35 +2509,82 @@ static void smack_sock_graft(struct sock *sk, struct socket *parent) static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, struct request_sock *req) { - struct netlbl_lsm_secattr skb_secattr; + u16 family = sk->sk_family; struct socket_smack *ssp = sk->sk_security; + struct netlbl_lsm_secattr secattr; + struct sockaddr_in addr; + struct iphdr *hdr; char smack[SMK_LABELLEN]; int rc; - if (skb == NULL) - return -EACCES; + /* handle mapped IPv4 packets arriving via IPv6 sockets */ + if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) + family = PF_INET; - netlbl_secattr_init(&skb_secattr); - rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr); + netlbl_secattr_init(&secattr); + rc = netlbl_skbuff_getattr(skb, family, &secattr); if (rc == 0) - smack_from_secattr(&skb_secattr, smack); + smack_from_secattr(&secattr, smack); else strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); - netlbl_secattr_destroy(&skb_secattr); + netlbl_secattr_destroy(&secattr); + /* - * Receiving a packet requires that the other end - * be able to write here. Read access is not required. - * - * If the request is successful save the peer's label - * so that SO_PEERCRED can report it. + * Receiving a packet requires that the other end be able to write + * here. Read access is not required. */ rc = smk_access(smack, ssp->smk_in, MAY_WRITE); - if (rc == 0) - strncpy(ssp->smk_packet, smack, SMK_MAXLEN); + if (rc != 0) + return rc; + + /* + * Save the peer's label in the request_sock so we can later setup + * smk_packet in the child socket so that SO_PEERCRED can report it. + */ + req->peer_secid = smack_to_secid(smack); + + /* + * We need to decide if we want to label the incoming connection here + * if we do we only need to label the request_sock and the stack will + * propogate the wire-label to the sock when it is created. + */ + hdr = ip_hdr(skb); + addr.sin_addr.s_addr = hdr->saddr; + rcu_read_lock(); + if (smack_host_label(&addr) == NULL) { + rcu_read_unlock(); + netlbl_secattr_init(&secattr); + smack_to_secattr(smack, &secattr); + rc = netlbl_req_setattr(req, &secattr); + netlbl_secattr_destroy(&secattr); + } else { + rcu_read_unlock(); + netlbl_req_delattr(req); + } return rc; } +/** + * smack_inet_csk_clone - Copy the connection information to the new socket + * @sk: the new socket + * @req: the connection's request_sock + * + * Transfer the connection's peer label to the newly created socket. + */ +static void smack_inet_csk_clone(struct sock *sk, + const struct request_sock *req) +{ + struct socket_smack *ssp = sk->sk_security; + char *smack; + + if (req->peer_secid != 0) { + smack = smack_from_secid(req->peer_secid); + strncpy(ssp->smk_packet, smack, SMK_MAXLEN); + } else + ssp->smk_packet[0] = '\0'; +} + /* * Key management security hooks * @@ -2911,6 +2936,7 @@ struct security_operations smack_ops = { .sk_free_security = smack_sk_free_security, .sock_graft = smack_sock_graft, .inet_conn_request = smack_inet_conn_request, + .inet_csk_clone = smack_inet_csk_clone, /* key management security hooks */ #ifdef CONFIG_KEYS -- cgit v1.2.3 From 4303154e86597885bc3cbc178a48ccbc8213875f Mon Sep 17 00:00:00 2001 From: Etienne Basset Date: Fri, 27 Mar 2009 17:11:01 -0400 Subject: smack: Add a new '-CIPSO' option to the network address label configuration This patch adds a new special option '-CIPSO' to the Smack subsystem. When used in the netlabel list, it means "use CIPSO networking". A use case is when your local network speaks CIPSO and you want also to connect to the unlabeled Internet. This patch also add some documentation describing that. The patch also corrects an oops when setting a '' SMACK64 xattr to a file. Signed-off-by: Etienne Basset Signed-off-by: Paul Moore Acked-by: Casey Schaufler Signed-off-by: James Morris --- Documentation/Smack.txt | 42 +++++++++++++++++++++++++++++++++++++----- security/smack/smack.h | 3 +++ security/smack/smack_access.c | 3 +++ security/smack/smack_lsm.c | 11 +++++++++-- security/smack/smackfs.c | 38 ++++++++++++++++++++++++++++++-------- 5 files changed, 82 insertions(+), 15 deletions(-) (limited to 'security/smack/smack.h') diff --git a/Documentation/Smack.txt b/Documentation/Smack.txt index 989c2fcd8111..629c92e99783 100644 --- a/Documentation/Smack.txt +++ b/Documentation/Smack.txt @@ -184,14 +184,16 @@ length. Single character labels using special characters, that being anything other than a letter or digit, are reserved for use by the Smack development team. Smack labels are unstructured, case sensitive, and the only operation ever performed on them is comparison for equality. Smack labels cannot -contain unprintable characters or the "/" (slash) character. +contain unprintable characters or the "/" (slash) character. Smack labels +cannot begin with a '-', which is reserved for special options. There are some predefined labels: - _ Pronounced "floor", a single underscore character. - ^ Pronounced "hat", a single circumflex character. - * Pronounced "star", a single asterisk character. - ? Pronounced "huh", a single question mark character. + _ Pronounced "floor", a single underscore character. + ^ Pronounced "hat", a single circumflex character. + * Pronounced "star", a single asterisk character. + ? Pronounced "huh", a single question mark character. + @ Pronounced "Internet", a single at sign character. Every task on a Smack system is assigned a label. System tasks, such as init(8) and systems daemons, are run with the floor ("_") label. User tasks @@ -412,6 +414,36 @@ sockets. A privileged program may set this to match the label of another task with which it hopes to communicate. +Smack Netlabel Exceptions + +You will often find that your labeled application has to talk to the outside, +unlabeled world. To do this there's a special file /smack/netlabel where you can +add some exceptions in the form of : +@IP1 LABEL1 or +@IP2/MASK LABEL2 + +It means that your application will have unlabeled access to @IP1 if it has +write access on LABEL1, and access to the subnet @IP2/MASK if it has write +access on LABEL2. + +Entries in the /smack/netlabel file are matched by longest mask first, like in +classless IPv4 routing. + +A special label '@' and an option '-CIPSO' can be used there : +@ means Internet, any application with any label has access to it +-CIPSO means standard CIPSO networking + +If you don't know what CIPSO is and don't plan to use it, you can just do : +echo 127.0.0.1 -CIPSO > /smack/netlabel +echo 0.0.0.0/0 @ > /smack/netlabel + +If you use CIPSO on your 192.168.0.0/16 local network and need also unlabeled +Internet access, you can have : +echo 127.0.0.1 -CIPSO > /smack/netlabel +echo 192.168.0.0/16 -CIPSO > /smack/netlabel +echo 0.0.0.0/0 @ > /smack/netlabel + + Writing Applications for Smack There are three sorts of applications that will run on a Smack system. How an diff --git a/security/smack/smack.h b/security/smack/smack.h index 5e5a3bcb599a..42ef313f9856 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -132,6 +132,8 @@ struct smack_known { #define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN #define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT +#define SMACK_CIPSO_OPTION "-CIPSO" + /* * How communications on this socket are treated. * Usually it's determined by the underlying netlabel code @@ -199,6 +201,7 @@ u32 smack_to_secid(const char *); extern int smack_cipso_direct; extern char *smack_net_ambient; extern char *smack_onlycap; +extern const char *smack_cipso_option; extern struct smack_known smack_known_floor; extern struct smack_known smack_known_hat; diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 58564195bb09..ac0a2707f6d4 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -261,6 +261,9 @@ char *smk_import(const char *string, int len) { struct smack_known *skp; + /* labels cannot begin with a '-' */ + if (string[0] == '-') + return NULL; skp = smk_import_entry(string, len); if (skp == NULL) return NULL; diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 8ed502c2ad45..921514902eca 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -609,6 +609,9 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name, strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { if (!capable(CAP_MAC_ADMIN)) rc = -EPERM; + /* a label cannot be void and cannot begin with '-' */ + if (size == 0 || (size > 0 && ((char *)value)[0] == '-')) + rc = -EINVAL; } else rc = cap_inode_setxattr(dentry, name, value, size, flags); @@ -1323,8 +1326,12 @@ static char *smack_host_label(struct sockaddr_in *sip) * so we have found the most specific match */ if ((&snp->smk_host.sin_addr)->s_addr == - (siap->s_addr & (&snp->smk_mask)->s_addr)) + (siap->s_addr & (&snp->smk_mask)->s_addr)) { + /* we have found the special CIPSO option */ + if (snp->smk_label == smack_cipso_option) + return NULL; return snp->smk_label; + } return NULL; } @@ -1486,7 +1493,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name, struct socket *sock; int rc = 0; - if (value == NULL || size > SMK_LABELLEN) + if (value == NULL || size > SMK_LABELLEN || size == 0) return -EACCES; sp = smk_import(value, size); diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index 856c8a287523..e03a7e19c73b 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -86,6 +86,9 @@ LIST_HEAD(smack_rule_list); static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT; +const char *smack_cipso_option = SMACK_CIPSO_OPTION; + + #define SEQ_READ_FINISHED 1 /* @@ -565,6 +568,11 @@ static ssize_t smk_write_cipso(struct file *file, const char __user *buf, goto unlockedout; } + /* labels cannot begin with a '-' */ + if (data[0] == '-') { + rc = -EINVAL; + goto unlockedout; + } data[count] = '\0'; rule = data; /* @@ -808,9 +816,18 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf, if (m > BEBITS) return -EINVAL; - sp = smk_import(smack, 0); - if (sp == NULL) - return -EINVAL; + /* if smack begins with '-', its an option, don't import it */ + if (smack[0] != '-') { + sp = smk_import(smack, 0); + if (sp == NULL) + return -EINVAL; + } else { + /* check known options */ + if (strcmp(smack, smack_cipso_option) == 0) + sp = (char *)smack_cipso_option; + else + return -EINVAL; + } for (temp_mask = 0; m > 0; m--) { temp_mask |= mask_bits; @@ -849,18 +866,23 @@ static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf, smk_netlbladdr_insert(skp); } } else { - rc = netlbl_cfg_unlbl_static_del(&init_net, NULL, - &skp->smk_host.sin_addr, &skp->smk_mask, - PF_INET, &audit_info); + /* we delete the unlabeled entry, only if the previous label + * wasnt the special CIPSO option */ + if (skp->smk_label != smack_cipso_option) + rc = netlbl_cfg_unlbl_static_del(&init_net, NULL, + &skp->smk_host.sin_addr, &skp->smk_mask, + PF_INET, &audit_info); + else + rc = 0; skp->smk_label = sp; } /* * Now tell netlabel about the single label nature of * this host so that incoming packets get labeled. + * but only if we didn't get the special CIPSO option */ - - if (rc == 0) + if (rc == 0 && sp != smack_cipso_option) rc = netlbl_cfg_unlbl_static_add(&init_net, NULL, &skp->smk_host.sin_addr, &skp->smk_mask, PF_INET, smack_to_secid(skp->smk_label), &audit_info); -- cgit v1.2.3