diff options
Diffstat (limited to 'security/smack/smack_lsm.c')
-rw-r--r-- | security/smack/smack_lsm.c | 237 |
1 files changed, 83 insertions, 154 deletions
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 45c32f074166..952b1f41fc78 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -30,7 +30,6 @@ #include <linux/slab.h> #include <linux/mutex.h> #include <linux/pipe_fs_i.h> -#include <net/netlabel.h> #include <net/cipso_ipv4.h> #include <linux/audit.h> #include <linux/magic.h> @@ -57,16 +56,23 @@ static char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp) { int rc; - char in[SMK_LABELLEN]; + char *buffer; + char *result = NULL; if (ip->i_op->getxattr == NULL) return NULL; - rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN); - if (rc < 0) + buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL); + if (buffer == NULL) return NULL; - return smk_import(in, rc); + rc = ip->i_op->getxattr(dp, name, buffer, SMK_LONGLABEL); + if (rc > 0) + result = smk_import(buffer, rc); + + kfree(buffer); + + return result; } /** @@ -79,7 +85,7 @@ struct inode_smack *new_inode_smack(char *smack) { struct inode_smack *isp; - isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL); + isp = kzalloc(sizeof(struct inode_smack), GFP_NOFS); if (isp == NULL) return NULL; @@ -556,13 +562,14 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, void **value, size_t *len) { struct smack_known *skp; + struct inode_smack *issp = inode->i_security; char *csp = smk_of_current(); char *isp = smk_of_inode(inode); char *dsp = smk_of_inode(dir); int may; if (name) { - *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL); + *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_NOFS); if (*name == NULL) return -ENOMEM; } @@ -577,12 +584,15 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, * If the access rule allows transmutation and * the directory requests transmutation then * by all means transmute. + * Mark the inode as changed. */ if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && - smk_inode_transmutable(dir)) + smk_inode_transmutable(dir)) { isp = dsp; + issp->smk_flags |= SMK_INODE_CHANGED; + } - *value = kstrdup(isp, GFP_KERNEL); + *value = kstrdup(isp, GFP_NOFS); if (*value == NULL) return -ENOMEM; } @@ -821,7 +831,7 @@ static int smack_inode_setxattr(struct dentry *dentry, const char *name, * check label validity here so import wont fail on * post_setxattr */ - if (size == 0 || size >= SMK_LABELLEN || + if (size == 0 || size >= SMK_LONGLABEL || smk_import(value, size) == NULL) rc = -EINVAL; } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { @@ -1820,65 +1830,6 @@ static char *smack_host_label(struct sockaddr_in *sip) } /** - * smack_set_catset - convert a capset to netlabel mls categories - * @catset: the Smack categories - * @sap: where to put the netlabel categories - * - * Allocates and fills attr.mls.cat - */ -static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap) -{ - unsigned char *cp; - unsigned char m; - int cat; - int rc; - int byte; - - if (!catset) - return; - - sap->flags |= NETLBL_SECATTR_MLS_CAT; - sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); - sap->attr.mls.cat->startbit = 0; - - for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++) - for (m = 0x80; m != 0; m >>= 1, cat++) { - if ((m & *cp) == 0) - continue; - rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat, - cat, GFP_ATOMIC); - } -} - -/** - * smack_to_secattr - fill a secattr from a smack value - * @smack: the smack value - * @nlsp: where the result goes - * - * Casey says that CIPSO is good enough for now. - * It can be used to effect. - * It can also be abused to effect when necessary. - * Apologies to the TSIG group in general and GW in particular. - */ -static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) -{ - struct smack_cipso cipso; - int rc; - - nlsp->domain = smack; - nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL; - - rc = smack_to_cipso(smack, &cipso); - if (rc == 0) { - nlsp->attr.mls.lvl = cipso.smk_level; - smack_set_catset(cipso.smk_catset, nlsp); - } else { - nlsp->attr.mls.lvl = smack_cipso_direct; - smack_set_catset(smack, nlsp); - } -} - -/** * smack_netlabel - Set the secattr on a socket * @sk: the socket * @labeled: socket label scheme @@ -1890,8 +1841,8 @@ static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) */ static int smack_netlabel(struct sock *sk, int labeled) { + struct smack_known *skp; struct socket_smack *ssp = sk->sk_security; - struct netlbl_lsm_secattr secattr; int rc = 0; /* @@ -1909,10 +1860,8 @@ static int smack_netlabel(struct sock *sk, int labeled) labeled == SMACK_UNLABELED_SOCKET) netlbl_sock_delattr(sk); else { - netlbl_secattr_init(&secattr); - smack_to_secattr(ssp->smk_out, &secattr); - rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr); - netlbl_secattr_destroy(&secattr); + skp = smk_find_entry(ssp->smk_out); + rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel); } bh_unlock_sock(sk); @@ -1985,7 +1934,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name, struct socket *sock; int rc = 0; - if (value == NULL || size > SMK_LABELLEN || size == 0) + if (value == NULL || size > SMK_LONGLABEL || size == 0) return -EACCES; sp = smk_import(value, size); @@ -2552,6 +2501,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) char *final; char trattr[TRANS_TRUE_SIZE]; int transflag = 0; + int rc; struct dentry *dp; if (inode == NULL) @@ -2670,17 +2620,38 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) */ dp = dget(opt_dentry); fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp); - if (fetched != NULL) { + if (fetched != NULL) final = fetched; - if (S_ISDIR(inode->i_mode)) { - trattr[0] = '\0'; - inode->i_op->getxattr(dp, + + /* + * Transmuting directory + */ + if (S_ISDIR(inode->i_mode)) { + /* + * If this is a new directory and the label was + * transmuted when the inode was initialized + * set the transmute attribute on the directory + * and mark the inode. + * + * If there is a transmute attribute on the + * directory mark the inode. + */ + if (isp->smk_flags & SMK_INODE_CHANGED) { + isp->smk_flags &= ~SMK_INODE_CHANGED; + rc = inode->i_op->setxattr(dp, XATTR_NAME_SMACKTRANSMUTE, - trattr, TRANS_TRUE_SIZE); - if (strncmp(trattr, TRANS_TRUE, - TRANS_TRUE_SIZE) == 0) - transflag = SMK_INODE_TRANSMUTE; + TRANS_TRUE, TRANS_TRUE_SIZE, + 0); + } else { + rc = inode->i_op->getxattr(dp, + XATTR_NAME_SMACKTRANSMUTE, trattr, + TRANS_TRUE_SIZE); + if (rc >= 0 && strncmp(trattr, TRANS_TRUE, + TRANS_TRUE_SIZE) != 0) + rc = -EINVAL; } + if (rc >= 0) + transflag = SMK_INODE_TRANSMUTE; } isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp); isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp); @@ -2759,7 +2730,7 @@ static int smack_setprocattr(struct task_struct *p, char *name, if (!capable(CAP_MAC_ADMIN)) return -EPERM; - if (value == NULL || size == 0 || size >= SMK_LABELLEN) + if (value == NULL || size == 0 || size >= SMK_LONGLABEL) return -EINVAL; if (strcmp(name, "current") != 0) @@ -2895,10 +2866,9 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, static char *smack_from_secattr(struct netlbl_lsm_secattr *sap, struct socket_smack *ssp) { - struct smack_known *skp; - char smack[SMK_LABELLEN]; + struct smack_known *kp; char *sp; - int pcat; + int found = 0; if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { /* @@ -2906,59 +2876,27 @@ static char *smack_from_secattr(struct netlbl_lsm_secattr *sap, * If there are flags but no level netlabel isn't * behaving the way we expect it to. * - * Get the categories, if any + * Look it up in the label table * Without guidance regarding the smack value * for the packet fall back on the network * ambient value. */ - memset(smack, '\0', SMK_LABELLEN); - if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0) - for (pcat = -1;;) { - pcat = netlbl_secattr_catmap_walk( - sap->attr.mls.cat, pcat + 1); - if (pcat < 0) - break; - smack_catset_bit(pcat, smack); - } - /* - * If it is CIPSO using smack direct mapping - * we are already done. WeeHee. - */ - if (sap->attr.mls.lvl == smack_cipso_direct) { - /* - * The label sent is usually on the label list. - * - * If it is not we may still want to allow the - * delivery. - * - * If the recipient is accepting all packets - * because it is using the star ("*") label - * for SMACK64IPIN provide the web ("@") label - * so that a directed response will succeed. - * This is not very correct from a MAC point - * of view, but gets around the problem that - * locking prevents adding the newly discovered - * label to the list. - * The case where the recipient is not using - * the star label should obviously fail. - * The easy way to do this is to provide the - * star label as the subject label. - */ - skp = smk_find_entry(smack); - if (skp != NULL) - return skp->smk_known; - if (ssp != NULL && - ssp->smk_in == smack_known_star.smk_known) - return smack_known_web.smk_known; - return smack_known_star.smk_known; + rcu_read_lock(); + list_for_each_entry(kp, &smack_known_list, list) { + if (sap->attr.mls.lvl != kp->smk_netlabel.attr.mls.lvl) + continue; + if (memcmp(sap->attr.mls.cat, + kp->smk_netlabel.attr.mls.cat, + SMK_CIPSOLEN) != 0) + continue; + found = 1; + break; } - /* - * Look it up in the supplied table if it is not - * a direct mapping. - */ - sp = smack_from_cipso(sap->attr.mls.lvl, smack); - if (sp != NULL) - return sp; + rcu_read_unlock(); + + if (found) + return kp->smk_known; + if (ssp != NULL && ssp->smk_in == smack_known_star.smk_known) return smack_known_web.smk_known; return smack_known_star.smk_known; @@ -3158,11 +3096,13 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, struct request_sock *req) { u16 family = sk->sk_family; + struct smack_known *skp; struct socket_smack *ssp = sk->sk_security; struct netlbl_lsm_secattr secattr; struct sockaddr_in addr; struct iphdr *hdr; char *sp; + char *hsp; int rc; struct smk_audit_info ad; #ifdef CONFIG_AUDIT @@ -3209,16 +3149,14 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, 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(sp, &secattr); - rc = netlbl_req_setattr(req, &secattr); - netlbl_secattr_destroy(&secattr); - } else { - rcu_read_unlock(); + hsp = smack_host_label(&addr); + rcu_read_unlock(); + + if (hsp == NULL) { + skp = smk_find_entry(sp); + rc = netlbl_req_setattr(req, &skp->smk_netlabel); + } else netlbl_req_delattr(req); - } return rc; } @@ -3400,7 +3338,7 @@ static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule, char *rule = vrule; if (!rule) { - audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR, + audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, "Smack: missing rule\n"); return -ENOENT; } @@ -3643,15 +3581,6 @@ struct security_operations smack_ops = { static __init void init_smack_known_list(void) { /* - * Initialize CIPSO locks - */ - spin_lock_init(&smack_known_huh.smk_cipsolock); - spin_lock_init(&smack_known_hat.smk_cipsolock); - spin_lock_init(&smack_known_star.smk_cipsolock); - spin_lock_init(&smack_known_floor.smk_cipsolock); - spin_lock_init(&smack_known_invalid.smk_cipsolock); - spin_lock_init(&smack_known_web.smk_cipsolock); - /* * Initialize rule list locks */ mutex_init(&smack_known_huh.smk_rules_lock); |