diff options
Diffstat (limited to 'security/selinux/hooks.c')
-rw-r--r-- | security/selinux/hooks.c | 446 |
1 files changed, 307 insertions, 139 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 21dad415b896..24caaeec8894 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -18,7 +18,6 @@ * as published by the Free Software Foundation. */ -#include <linux/config.h> #include <linux/module.h> #include <linux/init.h> #include <linux/kernel.h> @@ -69,6 +68,7 @@ #include <linux/sysctl.h> #include <linux/audit.h> #include <linux/string.h> +#include <linux/selinux.h> #include "avc.h" #include "objsec.h" @@ -80,6 +80,7 @@ extern unsigned int policydb_loaded_version; extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm); +extern int selinux_compat_net; #ifdef CONFIG_SECURITY_SELINUX_DEVELOP int selinux_enforcing = 0; @@ -696,6 +697,8 @@ static inline u16 socket_type_to_security_class(int family, int type, int protoc return SECCLASS_PACKET_SOCKET; case PF_KEY: return SECCLASS_KEY_SOCKET; + case PF_APPLETALK: + return SECCLASS_APPLETALK_SOCKET; } return SECCLASS_SOCKET; @@ -1096,6 +1099,17 @@ static int may_create(struct inode *dir, FILESYSTEM__ASSOCIATE, &ad); } +/* Check whether a task can create a key. */ +static int may_create_key(u32 ksid, + struct task_struct *ctx) +{ + struct task_security_struct *tsec; + + tsec = ctx->security; + + return avc_has_perm(tsec->sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL); +} + #define MAY_LINK 0 #define MAY_UNLINK 1 #define MAY_RMDIR 2 @@ -1518,8 +1532,10 @@ static int selinux_bprm_set_security(struct linux_binprm *bprm) /* Default to the current task SID. */ bsec->sid = tsec->sid; - /* Reset create SID on execve. */ + /* Reset fs, key, and sock SIDs on execve. */ tsec->create_sid = 0; + tsec->keycreate_sid = 0; + tsec->sockcreate_sid = 0; if (tsec->exec_sid) { newsid = tsec->exec_sid; @@ -1900,13 +1916,13 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data) return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad); } -static int selinux_sb_statfs(struct super_block *sb) +static int selinux_sb_statfs(struct dentry *dentry) { struct avc_audit_data ad; AVC_AUDIT_DATA_INIT(&ad,FS); - ad.u.fs.dentry = sb->s_root; - return superblock_has_perm(current, sb, FILESYSTEM__GETATTR, &ad); + ad.u.fs.dentry = dentry->d_sb->s_root; + return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad); } static int selinux_mount(char * dev_name, @@ -2571,9 +2587,11 @@ static int selinux_task_alloc_security(struct task_struct *tsk) tsec2->osid = tsec1->osid; tsec2->sid = tsec1->sid; - /* Retain the exec and create SIDs across fork */ + /* Retain the exec, fs, key, and sock SIDs across fork */ tsec2->exec_sid = tsec1->exec_sid; tsec2->create_sid = tsec1->create_sid; + tsec2->keycreate_sid = tsec1->keycreate_sid; + tsec2->sockcreate_sid = tsec1->sockcreate_sid; /* Retain ptracer SID across fork, if any. This will be reset by the ptrace hook upon any @@ -2625,6 +2643,11 @@ static int selinux_task_getsid(struct task_struct *p) return task_has_perm(current, p, PROCESS__GETSESSION); } +static void selinux_task_getsecid(struct task_struct *p, u32 *secid) +{ + selinux_get_task_sid(p, secid); +} + static int selinux_task_setgroups(struct group_info *group_info) { /* See the comment for setuid above. */ @@ -2642,6 +2665,16 @@ static int selinux_task_setnice(struct task_struct *p, int nice) return task_has_perm(current,p, PROCESS__SETSCHED); } +static int selinux_task_setioprio(struct task_struct *p, int ioprio) +{ + return task_has_perm(current, p, PROCESS__SETSCHED); +} + +static int selinux_task_getioprio(struct task_struct *p) +{ + return task_has_perm(current, p, PROCESS__GETSCHED); +} + static int selinux_task_setrlimit(unsigned int resource, struct rlimit *new_rlim) { struct rlimit *old_rlim = current->signal->rlim + resource; @@ -2671,12 +2704,19 @@ static int selinux_task_getscheduler(struct task_struct *p) return task_has_perm(current, p, PROCESS__GETSCHED); } -static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int sig) +static int selinux_task_movememory(struct task_struct *p) +{ + return task_has_perm(current, p, PROCESS__SETSCHED); +} + +static int selinux_task_kill(struct task_struct *p, struct siginfo *info, + int sig, u32 secid) { u32 perm; int rc; + struct task_security_struct *tsec; - rc = secondary_ops->task_kill(p, info, sig); + rc = secondary_ops->task_kill(p, info, sig, secid); if (rc) return rc; @@ -2687,8 +2727,12 @@ static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int si perm = PROCESS__SIGNULL; /* null signal; existence test */ else perm = signal_to_av(sig); - - return task_has_perm(current, p, perm); + tsec = p->security; + if (secid) + rc = avc_has_perm(secid, tsec->sid, SECCLASS_PROCESS, perm, NULL); + else + rc = task_has_perm(current, p, perm); + return rc; } static int selinux_task_prctl(int option, @@ -2913,12 +2957,14 @@ static int selinux_socket_create(int family, int type, { int err = 0; struct task_security_struct *tsec; + u32 newsid; if (kern) goto out; tsec = current->security; - err = avc_has_perm(tsec->sid, tsec->sid, + newsid = tsec->sockcreate_sid ? : tsec->sid; + err = avc_has_perm(tsec->sid, newsid, socket_type_to_security_class(family, type, protocol), SOCKET__CREATE, NULL); @@ -2931,12 +2977,14 @@ static void selinux_socket_post_create(struct socket *sock, int family, { struct inode_security_struct *isec; struct task_security_struct *tsec; + u32 newsid; isec = SOCK_INODE(sock)->i_security; tsec = current->security; + newsid = tsec->sockcreate_sid ? : tsec->sid; isec->sclass = socket_type_to_security_class(family, type, protocol); - isec->sid = kern ? SECINITSID_KERNEL : tsec->sid; + isec->sid = kern ? SECINITSID_KERNEL : newsid; isec->initialized = 1; return; @@ -3214,47 +3262,17 @@ static int selinux_socket_unix_may_send(struct socket *sock, return 0; } -static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) +static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb, + struct avc_audit_data *ad, u32 sock_sid, u16 sock_class, + u16 family, char *addrp, int len) { - u16 family; - char *addrp; - int len, err = 0; + int err = 0; u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0; - u32 sock_sid = 0; - u16 sock_class = 0; - struct socket *sock; - struct net_device *dev; - struct avc_audit_data ad; - - family = sk->sk_family; - if (family != PF_INET && family != PF_INET6) - goto out; - - /* Handle mapped IPv4 packets arriving via IPv6 sockets */ - if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) - family = PF_INET; - - read_lock_bh(&sk->sk_callback_lock); - sock = sk->sk_socket; - if (sock) { - struct inode *inode; - inode = SOCK_INODE(sock); - if (inode) { - struct inode_security_struct *isec; - isec = inode->i_security; - sock_sid = isec->sid; - sock_class = isec->sclass; - } - } - read_unlock_bh(&sk->sk_callback_lock); - if (!sock_sid) - goto out; - dev = skb->dev; - if (!dev) + if (!skb->dev) goto out; - err = sel_netif_sids(dev, &if_sid, NULL); + err = sel_netif_sids(skb->dev, &if_sid, NULL); if (err) goto out; @@ -3277,44 +3295,88 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) break; } - AVC_AUDIT_DATA_INIT(&ad, NET); - ad.u.net.netif = dev->name; - ad.u.net.family = family; - - err = selinux_parse_skb(skb, &ad, &addrp, &len, 1); - if (err) - goto out; - - err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, &ad); + err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, ad); if (err) goto out; - /* Fixme: this lookup is inefficient */ err = security_node_sid(family, addrp, len, &node_sid); if (err) goto out; - err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, &ad); + err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, ad); if (err) goto out; if (recv_perm) { u32 port_sid; - /* Fixme: make this more efficient */ err = security_port_sid(sk->sk_family, sk->sk_type, - sk->sk_protocol, ntohs(ad.u.net.sport), + sk->sk_protocol, ntohs(ad->u.net.sport), &port_sid); if (err) goto out; err = avc_has_perm(sock_sid, port_sid, - sock_class, recv_perm, &ad); + sock_class, recv_perm, ad); } - if (!err) - err = selinux_xfrm_sock_rcv_skb(sock_sid, skb); +out: + return err; +} +static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) +{ + u16 family; + u16 sock_class = 0; + char *addrp; + int len, err = 0; + u32 sock_sid = 0; + struct socket *sock; + struct avc_audit_data ad; + + family = sk->sk_family; + if (family != PF_INET && family != PF_INET6) + goto out; + + /* Handle mapped IPv4 packets arriving via IPv6 sockets */ + if (family == PF_INET6 && skb->protocol == ntohs(ETH_P_IP)) + family = PF_INET; + + read_lock_bh(&sk->sk_callback_lock); + sock = sk->sk_socket; + if (sock) { + struct inode *inode; + inode = SOCK_INODE(sock); + if (inode) { + struct inode_security_struct *isec; + isec = inode->i_security; + sock_sid = isec->sid; + sock_class = isec->sclass; + } + } + read_unlock_bh(&sk->sk_callback_lock); + if (!sock_sid) + goto out; + + AVC_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = skb->dev ? skb->dev->name : "[unknown]"; + ad.u.net.family = family; + + err = selinux_parse_skb(skb, &ad, &addrp, &len, 1); + if (err) + goto out; + + if (selinux_compat_net) + err = selinux_sock_rcv_skb_compat(sk, skb, &ad, sock_sid, + sock_class, family, + addrp, len); + else + err = avc_has_perm(sock_sid, skb->secmark, SECCLASS_PACKET, + PACKET__RECV, &ad); + if (err) + goto out; + + err = selinux_xfrm_sock_rcv_skb(sock_sid, skb); out: return err; } @@ -3374,7 +3436,13 @@ out: static int selinux_socket_getpeersec_dgram(struct sk_buff *skb, char **secdata, u32 *seclen) { int err = 0; - u32 peer_sid = selinux_socket_getpeer_dgram(skb); + u32 peer_sid; + + if (skb->sk->sk_family == PF_UNIX) + selinux_get_inode_sid(SOCK_INODE(skb->sk->sk_socket), + &peer_sid); + else + peer_sid = selinux_socket_getpeer_dgram(skb); if (peer_sid == SECSID_NULL) return -EINVAL; @@ -3386,8 +3454,6 @@ static int selinux_socket_getpeersec_dgram(struct sk_buff *skb, char **secdata, return 0; } - - static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority) { return sk_alloc_security(sk, family, priority); @@ -3454,42 +3520,18 @@ out: #ifdef CONFIG_NETFILTER -static unsigned int selinux_ip_postroute_last(unsigned int hooknum, - struct sk_buff **pskb, - const struct net_device *in, - const struct net_device *out, - int (*okfn)(struct sk_buff *), - u16 family) +static int selinux_ip_postroute_last_compat(struct sock *sk, struct net_device *dev, + struct inode_security_struct *isec, + struct avc_audit_data *ad, + u16 family, char *addrp, int len) { - char *addrp; - int len, err = NF_ACCEPT; + int err; u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0; - struct sock *sk; - struct socket *sock; - struct inode *inode; - struct sk_buff *skb = *pskb; - struct inode_security_struct *isec; - struct avc_audit_data ad; - struct net_device *dev = (struct net_device *)out; - sk = skb->sk; - if (!sk) - goto out; - - sock = sk->sk_socket; - if (!sock) - goto out; - - inode = SOCK_INODE(sock); - if (!inode) - goto out; - err = sel_netif_sids(dev, &if_sid, NULL); if (err) goto out; - isec = inode->i_security; - switch (isec->sclass) { case SECCLASS_UDP_SOCKET: netif_perm = NETIF__UDP_SEND; @@ -3509,55 +3551,88 @@ static unsigned int selinux_ip_postroute_last(unsigned int hooknum, break; } - - AVC_AUDIT_DATA_INIT(&ad, NET); - ad.u.net.netif = dev->name; - ad.u.net.family = family; - - err = selinux_parse_skb(skb, &ad, &addrp, - &len, 0) ? NF_DROP : NF_ACCEPT; - if (err != NF_ACCEPT) - goto out; - - err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, - netif_perm, &ad) ? NF_DROP : NF_ACCEPT; - if (err != NF_ACCEPT) + err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, netif_perm, ad); + if (err) goto out; - /* Fixme: this lookup is inefficient */ - err = security_node_sid(family, addrp, len, - &node_sid) ? NF_DROP : NF_ACCEPT; - if (err != NF_ACCEPT) + err = security_node_sid(family, addrp, len, &node_sid); + if (err) goto out; - err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, - node_perm, &ad) ? NF_DROP : NF_ACCEPT; - if (err != NF_ACCEPT) + err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, node_perm, ad); + if (err) goto out; if (send_perm) { u32 port_sid; - /* Fixme: make this more efficient */ err = security_port_sid(sk->sk_family, sk->sk_type, sk->sk_protocol, - ntohs(ad.u.net.dport), - &port_sid) ? NF_DROP : NF_ACCEPT; - if (err != NF_ACCEPT) + ntohs(ad->u.net.dport), + &port_sid); + if (err) goto out; err = avc_has_perm(isec->sid, port_sid, isec->sclass, - send_perm, &ad) ? NF_DROP : NF_ACCEPT; + send_perm, ad); } +out: + return err; +} + +static unsigned int selinux_ip_postroute_last(unsigned int hooknum, + struct sk_buff **pskb, + const struct net_device *in, + const struct net_device *out, + int (*okfn)(struct sk_buff *), + u16 family) +{ + char *addrp; + int len, err = 0; + struct sock *sk; + struct socket *sock; + struct inode *inode; + struct sk_buff *skb = *pskb; + struct inode_security_struct *isec; + struct avc_audit_data ad; + struct net_device *dev = (struct net_device *)out; - if (err != NF_ACCEPT) + sk = skb->sk; + if (!sk) goto out; - err = selinux_xfrm_postroute_last(isec->sid, skb); + sock = sk->sk_socket; + if (!sock) + goto out; + + inode = SOCK_INODE(sock); + if (!inode) + goto out; + + isec = inode->i_security; + AVC_AUDIT_DATA_INIT(&ad, NET); + ad.u.net.netif = dev->name; + ad.u.net.family = family; + + err = selinux_parse_skb(skb, &ad, &addrp, &len, 0); + if (err) + goto out; + + if (selinux_compat_net) + err = selinux_ip_postroute_last_compat(sk, dev, isec, &ad, + family, addrp, len); + else + err = avc_has_perm(isec->sid, skb->secmark, SECCLASS_PACKET, + PACKET__SEND, &ad); + + if (err) + goto out; + + err = selinux_xfrm_postroute_last(isec->sid, skb); out: - return err; + return err ? NF_DROP : NF_ACCEPT; } static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum, @@ -3586,32 +3661,32 @@ static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum, static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb) { - struct task_security_struct *tsec; - struct av_decision avd; int err; err = secondary_ops->netlink_send(sk, skb); if (err) return err; - tsec = current->security; - - avd.allowed = 0; - avc_has_perm_noaudit(tsec->sid, tsec->sid, - SECCLASS_CAPABILITY, ~0, &avd); - cap_mask(NETLINK_CB(skb).eff_cap, avd.allowed); - if (policydb_loaded_version >= POLICYDB_VERSION_NLCLASS) err = selinux_nlmsg_perm(sk, skb); return err; } -static int selinux_netlink_recv(struct sk_buff *skb) +static int selinux_netlink_recv(struct sk_buff *skb, int capability) { - if (!cap_raised(NETLINK_CB(skb).eff_cap, CAP_NET_ADMIN)) - return -EPERM; - return 0; + int err; + struct avc_audit_data ad; + + err = secondary_ops->netlink_recv(skb, capability); + if (err) + return err; + + AVC_AUDIT_DATA_INIT(&ad, CAP); + ad.u.cap = capability; + + return avc_has_perm(NETLINK_CB(skb).sid, NETLINK_CB(skb).sid, + SECCLASS_CAPABILITY, CAP_TO_MASK(capability), &ad); } static int ipc_alloc_security(struct task_struct *task, @@ -4114,6 +4189,10 @@ static int selinux_getprocattr(struct task_struct *p, sid = tsec->exec_sid; else if (!strcmp(name, "fscreate")) sid = tsec->create_sid; + else if (!strcmp(name, "keycreate")) + sid = tsec->keycreate_sid; + else if (!strcmp(name, "sockcreate")) + sid = tsec->sockcreate_sid; else return -EINVAL; @@ -4146,6 +4225,10 @@ static int selinux_setprocattr(struct task_struct *p, error = task_has_perm(current, p, PROCESS__SETEXEC); else if (!strcmp(name, "fscreate")) error = task_has_perm(current, p, PROCESS__SETFSCREATE); + else if (!strcmp(name, "keycreate")) + error = task_has_perm(current, p, PROCESS__SETKEYCREATE); + else if (!strcmp(name, "sockcreate")) + error = task_has_perm(current, p, PROCESS__SETSOCKCREATE); else if (!strcmp(name, "current")) error = task_has_perm(current, p, PROCESS__SETCURRENT); else @@ -4175,6 +4258,13 @@ static int selinux_setprocattr(struct task_struct *p, tsec->exec_sid = sid; else if (!strcmp(name, "fscreate")) tsec->create_sid = sid; + else if (!strcmp(name, "keycreate")) { + error = may_create_key(sid, p); + if (error) + return error; + tsec->keycreate_sid = sid; + } else if (!strcmp(name, "sockcreate")) + tsec->sockcreate_sid = sid; else if (!strcmp(name, "current")) { struct av_decision avd; @@ -4226,6 +4316,61 @@ static int selinux_setprocattr(struct task_struct *p, return size; } +#ifdef CONFIG_KEYS + +static int selinux_key_alloc(struct key *k, struct task_struct *tsk, + unsigned long flags) +{ + struct task_security_struct *tsec = tsk->security; + struct key_security_struct *ksec; + + ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL); + if (!ksec) + return -ENOMEM; + + ksec->obj = k; + if (tsec->keycreate_sid) + ksec->sid = tsec->keycreate_sid; + else + ksec->sid = tsec->sid; + k->security = ksec; + + return 0; +} + +static void selinux_key_free(struct key *k) +{ + struct key_security_struct *ksec = k->security; + + k->security = NULL; + kfree(ksec); +} + +static int selinux_key_permission(key_ref_t key_ref, + struct task_struct *ctx, + key_perm_t perm) +{ + struct key *key; + struct task_security_struct *tsec; + struct key_security_struct *ksec; + + key = key_ref_to_ptr(key_ref); + + tsec = ctx->security; + ksec = key->security; + + /* if no specific permissions are requested, we skip the + permission check. No serious, additional covert channels + appear to be created. */ + if (perm == 0) + return 0; + + return avc_has_perm(tsec->sid, ksec->sid, + SECCLASS_KEY, perm, NULL); +} + +#endif + static struct security_operations selinux_ops = { .ptrace = selinux_ptrace, .capget = selinux_capget, @@ -4304,11 +4449,15 @@ static struct security_operations selinux_ops = { .task_setpgid = selinux_task_setpgid, .task_getpgid = selinux_task_getpgid, .task_getsid = selinux_task_getsid, + .task_getsecid = selinux_task_getsecid, .task_setgroups = selinux_task_setgroups, .task_setnice = selinux_task_setnice, + .task_setioprio = selinux_task_setioprio, + .task_getioprio = selinux_task_getioprio, .task_setrlimit = selinux_task_setrlimit, .task_setscheduler = selinux_task_setscheduler, .task_getscheduler = selinux_task_getscheduler, + .task_movememory = selinux_task_movememory, .task_kill = selinux_task_kill, .task_wait = selinux_task_wait, .task_prctl = selinux_task_prctl, @@ -4374,10 +4523,18 @@ static struct security_operations selinux_ops = { .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, .xfrm_policy_clone_security = selinux_xfrm_policy_clone, .xfrm_policy_free_security = selinux_xfrm_policy_free, + .xfrm_policy_delete_security = selinux_xfrm_policy_delete, .xfrm_state_alloc_security = selinux_xfrm_state_alloc, .xfrm_state_free_security = selinux_xfrm_state_free, + .xfrm_state_delete_security = selinux_xfrm_state_delete, .xfrm_policy_lookup = selinux_xfrm_policy_lookup, #endif + +#ifdef CONFIG_KEYS + .key_alloc = selinux_key_alloc, + .key_free = selinux_key_free, + .key_permission = selinux_key_permission, +#endif }; static __init int selinux_init(void) @@ -4413,6 +4570,15 @@ static __init int selinux_init(void) } else { printk(KERN_INFO "SELinux: Starting in permissive mode\n"); } + +#ifdef CONFIG_KEYS + /* Add security information to initial keyrings */ + selinux_key_alloc(&root_user_keyring, current, + KEY_ALLOC_NOT_IN_QUOTA); + selinux_key_alloc(&root_session_keyring, current, + KEY_ALLOC_NOT_IN_QUOTA); +#endif + return 0; } @@ -4422,6 +4588,7 @@ void selinux_complete_init(void) /* Set up any superblocks initialized prior to the policy load. */ printk(KERN_INFO "SELinux: Setting up existing superblocks.\n"); + spin_lock(&sb_lock); spin_lock(&sb_security_lock); next_sb: if (!list_empty(&superblock_security_head)) { @@ -4430,19 +4597,20 @@ next_sb: struct superblock_security_struct, list); struct super_block *sb = sbsec->sb; - spin_lock(&sb_lock); sb->s_count++; - spin_unlock(&sb_lock); spin_unlock(&sb_security_lock); + spin_unlock(&sb_lock); down_read(&sb->s_umount); if (sb->s_root) superblock_doinit(sb, NULL); drop_super(sb); + spin_lock(&sb_lock); spin_lock(&sb_security_lock); list_del_init(&sbsec->list); goto next_sb; } spin_unlock(&sb_security_lock); + spin_unlock(&sb_lock); } /* SELinux requires early initialization in order to label |