diff options
Diffstat (limited to 'security/apparmor/net.c')
| -rw-r--r-- | security/apparmor/net.c | 189 |
1 files changed, 163 insertions, 26 deletions
diff --git a/security/apparmor/net.c b/security/apparmor/net.c index 77413a519117..45cf25605c34 100644 --- a/security/apparmor/net.c +++ b/security/apparmor/net.c @@ -8,6 +8,7 @@ * Copyright 2009-2017 Canonical Ltd. */ +#include "include/af_unix.h" #include "include/apparmor.h" #include "include/audit.h" #include "include/cred.h" @@ -24,6 +25,12 @@ struct aa_sfs_entry aa_sfs_entry_network[] = { { } }; +struct aa_sfs_entry aa_sfs_entry_networkv9[] = { + AA_SFS_FILE_STRING("af_mask", AA_SFS_AF_MASK), + AA_SFS_FILE_BOOLEAN("af_unix", 1), + { } +}; + static const char * const net_mask_names[] = { "unknown", "send", @@ -66,6 +73,42 @@ static const char * const net_mask_names[] = { "unknown", }; +static void audit_unix_addr(struct audit_buffer *ab, const char *str, + struct sockaddr_un *addr, int addrlen) +{ + int len = unix_addr_len(addrlen); + + if (!addr || len <= 0) { + audit_log_format(ab, " %s=none", str); + } else if (addr->sun_path[0]) { + audit_log_format(ab, " %s=", str); + audit_log_untrustedstring(ab, addr->sun_path); + } else { + audit_log_format(ab, " %s=\"@", str); + if (audit_string_contains_control(&addr->sun_path[1], len - 1)) + audit_log_n_hex(ab, &addr->sun_path[1], len - 1); + else + audit_log_format(ab, "%.*s", len - 1, + &addr->sun_path[1]); + audit_log_format(ab, "\""); + } +} + +static void audit_unix_sk_addr(struct audit_buffer *ab, const char *str, + const struct sock *sk) +{ + const struct unix_sock *u = unix_sk(sk); + + if (u && u->addr) { + int addrlen; + struct sockaddr_un *addr = aa_sunaddr(u, &addrlen); + + audit_unix_addr(ab, str, addr, addrlen); + } else { + audit_unix_addr(ab, str, NULL, 0); + + } +} /* audit callback for net specific fields */ void audit_net_cb(struct audit_buffer *ab, void *va) @@ -73,12 +116,12 @@ void audit_net_cb(struct audit_buffer *ab, void *va) struct common_audit_data *sa = va; struct apparmor_audit_data *ad = aad(sa); - if (address_family_names[sa->u.net->family]) + if (address_family_names[ad->common.u.net->family]) audit_log_format(ab, " family=\"%s\"", - address_family_names[sa->u.net->family]); + address_family_names[ad->common.u.net->family]); else audit_log_format(ab, " family=\"unknown(%d)\"", - sa->u.net->family); + ad->common.u.net->family); if (sock_type_names[ad->net.type]) audit_log_format(ab, " sock_type=\"%s\"", sock_type_names[ad->net.type]); @@ -98,6 +141,19 @@ void audit_net_cb(struct audit_buffer *ab, void *va) net_mask_names, NET_PERMS_MASK); } } + if (ad->common.u.net->family == PF_UNIX) { + if (ad->net.addr || !ad->common.u.net->sk) + audit_unix_addr(ab, "addr", + unix_addr(ad->net.addr), + ad->net.addrlen); + else + audit_unix_sk_addr(ab, "addr", ad->common.u.net->sk); + if (ad->request & NET_PEER_MASK) { + audit_unix_addr(ab, "peer_addr", + unix_addr(ad->net.peer.addr), + ad->net.peer.addrlen); + } + } if (ad->peer) { audit_log_format(ab, " peer="); aa_label_xaudit(ab, labels_ns(ad->subj_label), ad->peer, @@ -105,45 +161,123 @@ void audit_net_cb(struct audit_buffer *ab, void *va) } } +/* standard permission lookup pattern - supports early bailout */ +int aa_do_perms(struct aa_profile *profile, struct aa_policydb *policy, + aa_state_t state, u32 request, + struct aa_perms *p, struct apparmor_audit_data *ad) +{ + struct aa_perms perms; + + AA_BUG(!profile); + AA_BUG(!policy); + + + if (state || !p) + p = aa_lookup_perms(policy, state); + perms = *p; + aa_apply_modes_to_perms(profile, &perms); + return aa_check_perms(profile, &perms, request, ad, + audit_net_cb); +} + +/* only continue match if + * insufficient current perms at current state + * indicates there are more perms in later state + * Returns: perms struct if early match + */ +static struct aa_perms *early_match(struct aa_policydb *policy, + aa_state_t state, u32 request) +{ + struct aa_perms *p; + + p = aa_lookup_perms(policy, state); + if (((p->allow & request) != request) && (p->allow & AA_CONT_MATCH)) + return NULL; + return p; +} + +static aa_state_t aa_dfa_match_be16(struct aa_dfa *dfa, aa_state_t state, + u16 data) +{ + __be16 buffer = cpu_to_be16(data); + + return aa_dfa_match_len(dfa, state, (char *) &buffer, 2); +} + +/** + * aa_match_to_prot - match the af, type, protocol triplet + * @policy: policy being matched + * @state: state to start in + * @request: permissions being requested, ignored if @p == NULL + * @af: socket address family + * @type: socket type + * @protocol: socket protocol + * @p: output - pointer to permission associated with match + * @info: output - pointer to string describing failure + * + * RETURNS: state match stopped in. + * + * If @(p) is assigned a value the returned state will be the + * corresponding state. Will not set @p on failure or if match completes + * only if an early match occurs + */ +aa_state_t aa_match_to_prot(struct aa_policydb *policy, aa_state_t state, + u32 request, u16 af, int type, int protocol, + struct aa_perms **p, const char **info) +{ + state = aa_dfa_match_be16(policy->dfa, state, (u16)af); + if (!state) { + *info = "failed af match"; + return state; + } + state = aa_dfa_match_be16(policy->dfa, state, (u16)type); + if (state) { + if (p) + *p = early_match(policy, state, request); + if (!p || !*p) { + state = aa_dfa_match_be16(policy->dfa, state, (u16)protocol); + if (!state) + *info = "failed protocol match"; + } + } else { + *info = "failed type match"; + } + + return state; +} + /* Generic af perm */ int aa_profile_af_perm(struct aa_profile *profile, struct apparmor_audit_data *ad, u32 request, u16 family, - int type) + int type, int protocol) { - struct aa_ruleset *rules = list_first_entry(&profile->rules, - typeof(*rules), list); - struct aa_perms perms = { }; + struct aa_ruleset *rules = profile->label.rules[0]; + struct aa_perms *p = NULL; aa_state_t state; - __be16 buffer[2]; AA_BUG(family >= AF_MAX); AA_BUG(type < 0 || type >= SOCK_MAX); + AA_BUG(profile_unconfined(profile)); if (profile_unconfined(profile)) return 0; - state = RULE_MEDIATES(rules, AA_CLASS_NET); + state = RULE_MEDIATES_NET(rules); if (!state) return 0; - - buffer[0] = cpu_to_be16(family); - buffer[1] = cpu_to_be16((u16) type); - state = aa_dfa_match_len(rules->policy->dfa, state, (char *) &buffer, - 4); - perms = *aa_lookup_perms(rules->policy, state); - aa_apply_modes_to_perms(profile, &perms); - - return aa_check_perms(profile, &perms, request, ad, audit_net_cb); + state = aa_match_to_prot(rules->policy, state, request, family, type, + protocol, &p, &ad->info); + return aa_do_perms(profile, rules->policy, state, request, p, ad); } int aa_af_perm(const struct cred *subj_cred, struct aa_label *label, const char *op, u32 request, u16 family, int type, int protocol) { struct aa_profile *profile; - DEFINE_AUDIT_NET(ad, op, NULL, family, type, protocol); + DEFINE_AUDIT_NET(ad, op, subj_cred, NULL, family, type, protocol); return fn_for_each_confined(label, profile, aa_profile_af_perm(profile, &ad, request, family, - type)); + type, protocol)); } static int aa_label_sk_perm(const struct cred *subj_cred, @@ -157,9 +291,9 @@ static int aa_label_sk_perm(const struct cred *subj_cred, AA_BUG(!label); AA_BUG(!sk); - if (ctx->label != kernel_t && !unconfined(label)) { + if (rcu_access_pointer(ctx->label) != kernel_t && !unconfined(label)) { struct aa_profile *profile; - DEFINE_AUDIT_SK(ad, op, sk); + DEFINE_AUDIT_SK(ad, op, subj_cred, sk); ad.subj_cred = subj_cred; error = fn_for_each_confined(label, profile, @@ -187,12 +321,16 @@ int aa_sk_perm(const char *op, u32 request, struct sock *sk) int aa_sock_file_perm(const struct cred *subj_cred, struct aa_label *label, - const char *op, u32 request, struct socket *sock) + const char *op, u32 request, struct file *file) { + struct socket *sock = (struct socket *) file->private_data; + AA_BUG(!label); AA_BUG(!sock); AA_BUG(!sock->sk); + if (sock->sk->sk_family == PF_UNIX) + return aa_unix_file_perm(subj_cred, label, op, request, file); return aa_label_sk_perm(subj_cred, label, op, request, sock->sk); } @@ -223,8 +361,7 @@ static int aa_secmark_perm(struct aa_profile *profile, u32 request, u32 secid, { int i, ret; struct aa_perms perms = { }; - struct aa_ruleset *rules = list_first_entry(&profile->rules, - typeof(*rules), list); + struct aa_ruleset *rules = profile->label.rules[0]; if (rules->secmark_count == 0) return 0; @@ -257,7 +394,7 @@ int apparmor_secmark_check(struct aa_label *label, char *op, u32 request, u32 secid, const struct sock *sk) { struct aa_profile *profile; - DEFINE_AUDIT_SK(ad, op, sk); + DEFINE_AUDIT_SK(ad, op, NULL, sk); return fn_for_each_confined(label, profile, aa_secmark_perm(profile, request, secid, |